Genotype- phenotype correlation in trisomy X: a retrospective study of a selected group of 36 patients and review of literature.

PubMed

Butnariu, Lăcrămioara; Rusu, Cristina; Caba, Lavinia; Pânzaru, Monica; Braha, Elena; Grămescu, Mihaela; Popescu, Roxana; Bujoranu, C; Gorduza, E V

2013-01-01

Trisomy X (47,XXX) is a gonosomal aneuploidy characterized by the presence of an extra X chromosome in a female person. Usually the diagnosis is established made postnatally by chromosome analysis in patients with suggestive clinical signs. Clinical signs vary by age. In prepubertal patients have a growth retardation associated with uncharacteristic facial dysmorphism, mild mental retardation with behavioral disorders, plus clinical signs of ovarian dysgenesis, postpubertal. We analyzed retrospectively the genotype - phenotype correlations for a selected group of 36 patients diagnosed with trisomy X (homogeneous or mosaic) by cytogenetic methods (X chromatin and karyotype). Analysis of the clinical data of 36 patients diagnosed with trisomy X and correlation with the results of X chromatin and karyotype. Clinical signs detected in patients with homogeneous trisomy X 47,XXX (22.22%), mosaic 46,XX/47,XXX (16.66%) or 47,XXX/48,XXXX (5.55%) were prepubertal, growth retardation associated with dysmorphic facial (upslanted palpebral fissure, epichantus, thin lips) and postpubertal, signs of ovarian dysgenesis (secondary amenorrhea, early menopause). The phenotype of patients with different gonosomal mosaic corresponding to Turner syndrome, incorporating a cell line with trisomy X (55.55%) was variable, correlated with the type of chromosomal abnormalities detected. The results of our study are similar to those obtained in other studies and emphasizes that phenotypic variability of patients with trisomy X feature makes it difficult to genotype - phenotype correlations.

Genotypic and Phenotypic Correlations of Multidrug-Resistant Acinetobacter baumannii-A. calcoaceticus Complex Strains Isolated from Patients at the National Naval Medical Center

USDA-ARS?s Scientific Manuscript database

Acinetobacter baumannii-calcoaceticus complex (ABC) infections have complicated the care of U.S. combat casualties. In this study, 102 ABC isolates from wounded soldiers treated at National Naval Medical Center (NNMC) were characterized by phenotype and genotype to identify clones in this population...

Correlation between Relatives given Complete Genotypes: from Identity by Descent to Identity by Function

PubMed Central

Sverdlov, Serge; Thompson, Elizabeth A.

2013-01-01

In classical quantitative genetics, the correlation between the phenotypes of individuals with unknown genotypes and a known pedigree relationship is expressed in terms of probabilities of IBD states. In existing approaches to the inverse problem where genotypes are observed but pedigree relationships are not, dependence between phenotypes is either modeled as Bayesian uncertainty or mapped to an IBD model via inferred relatedness parameters. Neither approach yields a relationship between genotypic similarity and phenotypic similarity with a probabilistic interpretation corresponding to a generative model. We introduce a generative model for diploid allele effect based on the classic infinite allele mutation process. This approach motivates the concept of IBF (Identity by Function). The phenotypic covariance between two individuals given their diploid genotypes is expressed in terms of functional identity states. The IBF parameters define a genetic architecture for a trait without reference to specific alleles or population. Given full genome sequences, we treat a gene-scale functional region, rather than a SNP, as a QTL, modeling patterns of dominance for multiple alleles. Applications demonstrated by simulation include phenotype and effect prediction and association, and estimation of heritability and classical variance components. A simulation case study of the Missing Heritability problem illustrates a decomposition of heritability under the IBF framework into Explained and Unexplained components. PMID:23851163

Mutation Spectrum and Phenotypic Features in Noonan Syndrome with PTPN11 Mutations: Definition of Two Novel Mutations.

PubMed

Atik, Tahir; Aykut, Ayca; Hazan, Filiz; Onay, Huseyin; Goksen, Damla; Darcan, Sukran; Tukun, Ajlan; Ozkinay, Ferda

2016-06-01

To evaluate the spectrum of PTPN11 gene mutations in Noonan syndrome patients and to study the genotype-phenotype associations. In this study, twenty Noonan syndrome patients with PTPN11 mutations were included. The patients underwent a detailed clinical and physical evaluation. To identify inherited cases, parents of all mutation positive patients were analyzed. Thirteen different PTPN11 mutations, two of them being novel, were detected in the study group. These mutations included eleven missense mutations: p.G60A, p.D61N, p.Y62D, p.Y63C, p.E69Q, p.Q79R, p.Y279C,p.N308D, p.N308S, p.M504V, p.Q510R and two novel missense mutations: p.I56V and p.I282M. The frequency of cardiac abnormalities and short stature were found to be 80 % and 80 %, respectively. Mental retardation was not observed in patients having exon 8 mutations. No significant correlations were detected between other phenotypic features and genotypes. By identifying genotype-phenotype correlations, this study provides information on phenotypes observed in NS patients with different PTPN11 mutations.

[Genotype/phenotype correlation in autism: genetic models and phenotypic characterization].

PubMed

Bonnet-Brilhault, F

2011-02-01

Autism spectrum disorders are a class of conditions categorized by communication problems, ritualistic behaviors, and deficits in social behaviors. This class of disorders merges a heterogeneous group of neurodevelopmental disorders regarding some phenotypic and probably physiopathological aspects. Genetic basis is well admitted, however, considering phenotypic and genotypic heterogeneity, correspondences between genotype and phenotype have yet to be established. To better identify such correspondences, genetic models have to be identified and phenotypic markers have to be characterized. Recent insights show that a variety of genetic mechanisms may be involved in autism spectrum disorders, i.e. single gene disorders, copy number variations and polygenic mechanisms. These current genetic models are described. Regarding clinical aspects, several approaches can be used in genetic studies. Nosographical approach, especially with the concept of autism spectrum disorders, merges a large group of disorders with clinical heterogeneity and may fail to identify clear genotype/phenotype correlations. Dimensional approach referred in genetic studies to the notion of "Broad Autism Phenotype" related to a constellation of language, personality, and social-behavioral features present in relatives that mirror the symptom domains of autism, but are much milder in expression. Studies of this broad autism phenotype may provide a potentially important complementary approach for detecting the genes involved in these domains. However, control population used in those studies need to be well characterized too. Identification of endophenotypes seems to offer more promising results. Endophenotypes, which are supposed to be more proximal markers of gene action in the same biological pathway, linking genes and complex clinical symptoms, are thought to be less genetically complex than the broader disease phenotype, indexing a limited aspect of genetic risk for the disorder as a whole. However, strategies useful to characterize such phenotypic markers (for example, electrophysiological markers) have to take into account that autism is an early neurodevelopmental disorder occurring during childhood when brain development and maturation are in process. Recent genetic results have improved our knowledge in genetic basis in autism. Nevertheless, correspondences with phenotypic markers remain challenging according to phenotypic and genotypic heterogeneity. Copyright © 2010 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Developmental mechanisms underlying variation in craniofacial disease and evolution.

PubMed

Fish, Jennifer L

2016-07-15

Craniofacial disease phenotypes exhibit significant variation in penetrance and severity. Although many genetic contributions to phenotypic variation have been identified, genotype-phenotype correlations remain imprecise. Recent work in evolutionary developmental biology has exposed intriguing developmental mechanisms that potentially explain incongruities in genotype-phenotype relationships. This review focuses on two observations from work in comparative and experimental animal model systems that highlight how development structures variation. First, multiple genetic inputs converge on relatively few developmental processes. Investigation of when and how variation in developmental processes occurs may therefore help predict potential genetic interactions and phenotypic outcomes. Second, genetic mutation is typically associated with an increase in phenotypic variance. Several models outlining developmental mechanisms underlying mutational increases in phenotypic variance are discussed using Satb2-mediated variation in jaw size as an example. These data highlight development as a critical mediator of genotype-phenotype correlations. Future research in evolutionary developmental biology focusing on tissue-level processes may help elucidate the "black box" between genotype and phenotype, potentially leading to novel treatment, earlier diagnoses, and better clinical consultations for individuals affected by craniofacial anomalies. Copyright © 2015 Elsevier Inc. All rights reserved.

Cow genotyping strategies for genomic selection in a small dairy cattle population.

PubMed

Jenko, J; Wiggans, G R; Cooper, T A; Eaglen, S A E; Luff, W G de L; Bichard, M; Pong-Wong, R; Woolliams, J A

2017-01-01

This study compares how different cow genotyping strategies increase the accuracy of genomic estimated breeding values (EBV) in dairy cattle breeds with low numbers. In these breeds, few sires have progeny records, and genotyping cows can improve the accuracy of genomic EBV. The Guernsey breed is a small dairy cattle breed with approximately 14,000 recorded individuals worldwide. Predictions of phenotypes of milk yield, fat yield, protein yield, and calving interval were made for Guernsey cows from England and Guernsey Island using genomic EBV, with training sets including 197 de-regressed proofs of genotyped bulls, with cows selected from among 1,440 genotyped cows using different genotyping strategies. Accuracies of predictions were tested using 10-fold cross-validation among the cows. Genomic EBV were predicted using 4 different methods: (1) pedigree BLUP, (2) genomic BLUP using only bulls, (3) univariate genomic BLUP using bulls and cows, and (4) bivariate genomic BLUP. Genotyping cows with phenotypes and using their data for the prediction of single nucleotide polymorphism effects increased the correlation between genomic EBV and phenotypes compared with using only bulls by 0.163±0.022 for milk yield, 0.111±0.021 for fat yield, and 0.113±0.018 for protein yield; a decrease of 0.014±0.010 for calving interval from a low base was the only exception. Genetic correlation between phenotypes from bulls and cows were approximately 0.6 for all yield traits and significantly different from 1. Only a very small change occurred in correlation between genomic EBV and phenotypes when using the bivariate model. It was always better to genotype all the cows, but when only half of the cows were genotyped, a divergent selection strategy was better compared with the random or directional selection approach. Divergent selection of 30% of the cows remained superior for the yield traits in 8 of 10 folds. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Duffy blood group phenotype-genotype correlations using high-resolution melting analysis PCR and microarray reveal complex cases including a new null FY*A allele: the role for sequencing in genotyping algorithms.

PubMed

Lopez, G H; Morrison, J; Condon, J A; Wilson, B; Martin, J R; Liew, Y-W; Flower, R L; Hyland, C A

2015-10-01

Duffy blood group phenotypes can be predicted by genotyping for single nucleotide polymorphisms (SNPs) responsible for the Fy(a) /Fy(b) polymorphism, for weak Fy(b) antigen, and for the red cell null Fy(a-b-) phenotype. This study correlates Duffy phenotype predictions with serotyping to assess the most reliable procedure for typing. Samples, n = 155 (135 donors and 20 patients), were genotyped by high-resolution melt PCR and by microarray. Samples were in three serology groups: 1) Duffy patterns expected n = 79, 2) weak and equivocal Fy(b) patterns n = 29 and 3) Fy(a-b-) n = 47 (one with anti-Fy3 antibody). Discrepancies were observed for five samples. For two, SNP genotyping predicted weak Fy(b) expression discrepant with Fy(b-) (Group 1 and 3). For three, SNP genotyping predicted Fy(a) , discrepant with Fy(a-b-) (Group 3). DNA sequencing identified silencing mutations in these FY*A alleles. One was a novel FY*A 719delG. One, the sample with the anti-Fy3, was homozygous for a 14-bp deletion (FY*01N.02); a true null. Both the high-resolution melting analysis and SNP microarray assays were concordant and showed genotyping, as well as phenotyping, is essential to ensure 100% accuracy for Duffy blood group assignments. Sequencing is important to resolve phenotype/genotype conflicts which here identified alleles, one novel, that carry silencing mutations. The risk of alloimmunisation may be dependent on this zygosity status. © 2015 International Society of Blood Transfusion.

Using Extended Genealogy to Estimate Components of Heritability for 23 Quantitative and Dichotomous Traits

PubMed Central

Zaitlen, Noah; Kraft, Peter; Patterson, Nick; Pasaniuc, Bogdan; Bhatia, Gaurav; Pollack, Samuela; Price, Alkes L.

2013-01-01

Important knowledge about the determinants of complex human phenotypes can be obtained from the estimation of heritability, the fraction of phenotypic variation in a population that is determined by genetic factors. Here, we make use of extensive phenotype data in Iceland, long-range phased genotypes, and a population-wide genealogical database to examine the heritability of 11 quantitative and 12 dichotomous phenotypes in a sample of 38,167 individuals. Most previous estimates of heritability are derived from family-based approaches such as twin studies, which may be biased upwards by epistatic interactions or shared environment. Our estimates of heritability, based on both closely and distantly related pairs of individuals, are significantly lower than those from previous studies. We examine phenotypic correlations across a range of relationships, from siblings to first cousins, and find that the excess phenotypic correlation in these related individuals is predominantly due to shared environment as opposed to dominance or epistasis. We also develop a new method to jointly estimate narrow-sense heritability and the heritability explained by genotyped SNPs. Unlike existing methods, this approach permits the use of information from both closely and distantly related pairs of individuals, thereby reducing the variance of estimates of heritability explained by genotyped SNPs while preventing upward bias. Our results show that common SNPs explain a larger proportion of the heritability than previously thought, with SNPs present on Illumina 300K genotyping arrays explaining more than half of the heritability for the 23 phenotypes examined in this study. Much of the remaining heritability is likely to be due to rare alleles that are not captured by standard genotyping arrays. PMID:23737753

Using extended genealogy to estimate components of heritability for 23 quantitative and dichotomous traits.

PubMed

Zaitlen, Noah; Kraft, Peter; Patterson, Nick; Pasaniuc, Bogdan; Bhatia, Gaurav; Pollack, Samuela; Price, Alkes L

2013-05-01

Important knowledge about the determinants of complex human phenotypes can be obtained from the estimation of heritability, the fraction of phenotypic variation in a population that is determined by genetic factors. Here, we make use of extensive phenotype data in Iceland, long-range phased genotypes, and a population-wide genealogical database to examine the heritability of 11 quantitative and 12 dichotomous phenotypes in a sample of 38,167 individuals. Most previous estimates of heritability are derived from family-based approaches such as twin studies, which may be biased upwards by epistatic interactions or shared environment. Our estimates of heritability, based on both closely and distantly related pairs of individuals, are significantly lower than those from previous studies. We examine phenotypic correlations across a range of relationships, from siblings to first cousins, and find that the excess phenotypic correlation in these related individuals is predominantly due to shared environment as opposed to dominance or epistasis. We also develop a new method to jointly estimate narrow-sense heritability and the heritability explained by genotyped SNPs. Unlike existing methods, this approach permits the use of information from both closely and distantly related pairs of individuals, thereby reducing the variance of estimates of heritability explained by genotyped SNPs while preventing upward bias. Our results show that common SNPs explain a larger proportion of the heritability than previously thought, with SNPs present on Illumina 300K genotyping arrays explaining more than half of the heritability for the 23 phenotypes examined in this study. Much of the remaining heritability is likely to be due to rare alleles that are not captured by standard genotyping arrays.

Genotype-Phenotype Relationship in Patients and Relatives with SHOX Region Anomalies in the French Population.

PubMed

Auger, Julie; Baptiste, Amandine; Benabbad, Imane; Thierry, Gaëlle; Costa, Jean-Marc; Amouyal, Mélanie; Kottler, Marie-Laure; Leheup, Bruno; Touraine, Renaud; Schmitt, Sébastien; Lebrun, Marine; Cormier Daire, Valérie; Bonnefont, Jean-Paul; de Roux, Nicolas; Elie, Caroline; Rosilio, Myriam

2016-01-01

The aim of our study was to describe a large population with anomalies involving the SHOX region, responsible for idiopathic short stature and Léri-Weill dyschondrosteosis (LWD), and to identify a possible genotype/phenotype correlation. We performed a retrospective multicenter study on French subjects with a SHOX region anomaly diagnosed by multiplex ligation-dependent probe amplification or Sanger sequencing. Phenotypes were collected in each of the 7 genetic laboratories practicing this technique for SHOX analysis. Among 205 index cases and 100 related cases, 91.3% had LWD. For index cases, median age at evaluation was 11.7 (9.0; 15.9) years and mean height standard deviation score was -2.3 ± 1.1. A deletion of either SHOX or PAR1 or both was found in 74% of patients. Duplications and point mutations/indels affected 8 and 18% of the population, respectively. Genotype-phenotype correlation showed that deletions were more frequently associated with Madelung deformity and mesomelic shortening in girls, as well as with presence of radiologic anomalies, than duplications. Our results highlight genotype-phenotype relationships in the French population with a SHOX defect and provide new information showing that clinical expression is milder in cases of duplication compared to deletions. © 2016 S. Karger AG, Basel.

The use of imputed sibling genotypes in sibship-based association analysis: on modeling alternatives, power and model misspecification.

PubMed

Minică, Camelia C; Dolan, Conor V; Hottenga, Jouke-Jan; Willemsen, Gonneke; Vink, Jacqueline M; Boomsma, Dorret I

2013-05-01

When phenotypic, but no genotypic data are available for relatives of participants in genetic association studies, previous research has shown that family-based imputed genotypes can boost the statistical power when included in such studies. Here, using simulations, we compared the performance of two statistical approaches suitable to model imputed genotype data: the mixture approach, which involves the full distribution of the imputed genotypes and the dosage approach, where the mean of the conditional distribution features as the imputed genotype. Simulations were run by varying sibship size, size of the phenotypic correlations among siblings, imputation accuracy and minor allele frequency of the causal SNP. Furthermore, as imputing sibling data and extending the model to include sibships of size two or greater requires modeling the familial covariance matrix, we inquired whether model misspecification affects power. Finally, the results obtained via simulations were empirically verified in two datasets with continuous phenotype data (height) and with a dichotomous phenotype (smoking initiation). Across the settings considered, the mixture and the dosage approach are equally powerful and both produce unbiased parameter estimates. In addition, the likelihood-ratio test in the linear mixed model appears to be robust to the considered misspecification in the background covariance structure, given low to moderate phenotypic correlations among siblings. Empirical results show that the inclusion in association analysis of imputed sibling genotypes does not always result in larger test statistic. The actual test statistic may drop in value due to small effect sizes. That is, if the power benefit is small, that the change in distribution of the test statistic under the alternative is relatively small, the probability is greater of obtaining a smaller test statistic. As the genetic effects are typically hypothesized to be small, in practice, the decision on whether family-based imputation could be used as a means to increase power should be informed by prior power calculations and by the consideration of the background correlation.

Environmental Response and Genomic Regions Correlated with Rice Root Growth and Yield under Drought in the OryzaSNP Panel across Multiple Study Systems

PubMed Central

Wade, Len J.; Bartolome, Violeta; Mauleon, Ramil; Vasant, Vivek Deshmuck; Prabakar, Sumeet Mankar; Chelliah, Muthukumar; Kameoka, Emi; Nagendra, K.; Reddy, K. R. Kamalnath; Varma, C. Mohan Kumar; Patil, Kalmeshwar Gouda; Shrestha, Roshi; Al-Shugeairy, Zaniab; Al-Ogaidi, Faez; Munasinghe, Mayuri; Gowda, Veeresh; Semon, Mande; Suralta, Roel R.; Shenoy, Vinay; Vadez, Vincent; Serraj, Rachid; Shashidhar, H. E.; Yamauchi, Akira; Babu, Ranganathan Chandra; Price, Adam; McNally, Kenneth L.; Henry, Amelia

2015-01-01

The rapid progress in rice genotyping must be matched by advances in phenotyping. A better understanding of genetic variation in rice for drought response, root traits, and practical methods for studying them are needed. In this study, the OryzaSNP set (20 diverse genotypes that have been genotyped for SNP markers) was phenotyped in a range of field and container studies to study the diversity of rice root growth and response to drought. Of the root traits measured across more than 20 root experiments, root dry weight showed the most stable genotypic performance across studies. The environment (E) component had the strongest effect on yield and root traits. We identified genomic regions correlated with root dry weight, percent deep roots, maximum root depth, and grain yield based on a correlation analysis with the phenotypes and aus, indica, or japonica introgression regions using the SNP data. Two genomic regions were identified as hot spots in which root traits and grain yield were co-located; on chromosome 1 (39.7–40.7 Mb) and on chromosome 8 (20.3–21.9 Mb). Across experiments, the soil type/ growth medium showed more correlations with plant growth than the container dimensions. Although the correlations among studies and genetic co-location of root traits from a range of study systems points to their potential utility to represent responses in field studies, the best correlations were observed when the two setups had some similar properties. Due to the co-location of the identified genomic regions (from introgression block analysis) with QTL for a number of previously reported root and drought traits, these regions are good candidates for detailed characterization to contribute to understanding rice improvement for response to drought. This study also highlights the utility of characterizing a small set of 20 genotypes for root growth, drought response, and related genomic regions. PMID:25909711

CYP2C9 Genotype vs. Metabolic Phenotype for Individual Drug Dosing—A Correlation Analysis Using Flurbiprofen as Probe Drug

PubMed Central

Vogl, Silvia; Lutz, Roman W.; Schönfelder, Gilbert; Lutz, Werner K.

2015-01-01

Currently, genotyping of patients for polymorphic enzymes responsible for metabolic elimination is considered a possibility to adjust drug dose levels. For a patient to profit from this procedure, the interindividual differences in drug metabolism within one genotype should be smaller than those between different genotypes. We studied a large cohort of healthy young adults (283 subjects), correlating their CYP2C9 genotype to a simple phenotyping metric, using flurbiprofen as probe drug. Genotyping was conducted for CYP2C9*1, *2, *3. The urinary metabolic ratio MR (concentration of CYP2C9-dependent metabolite divided by concentration of flurbiprofen) determined two hours after flurbiprofen (8.75 mg) administration served as phenotyping metric. Linear statistical models correlating genotype and phenotype provided highly significant allele-specific MR estimates of 0.596 for the wild type allele CYP2C9*1, 0.405 for CYP2C9*2 (68 % of wild type), and 0.113 for CYP2C9*3 (19 % of wild type). If these estimates were used for flurbiprofen dose adjustment, taking 100 % for genotype *1/*1, an average reduction to 84 %, 60 %, 68 %, 43 %, and 19 % would result for genotype *1/*2, *1/*3, *2/*2, *2/*3, and *3/*3, respectively. Due to the large individual variation within genotypes with coefficients of variation ≥ 20 % and supposing the normal distribution, one in three individuals would be out of the average optimum dose by more than 20 %, one in 20 would be 40 % off. Whether this problem also applies to other CYPs and other drugs has to be investigated case by case. Our data for the given example, however, puts the benefit of individual drug dosing to question, if it is exclusively based on genotype. PMID:25775139

Evidence of true genotype-phenotype correlation in primary hyperoxaluria type 1.

PubMed

Hoppe, Bernd

2010-03-01

A genotype-phenotype correlation in patients with primary hyperoxaluria type 1 and specific AGXT mutations has supposedly been found, at least for sensitivity to medication and long-term outcome. Nevertheless, other determinants, such as environmental factors or modifier genes, must play an essential role in the intra- and interfamilial heterogeneity of this disease. Harambat and co-workers report on this situation, presenting data on a major population of genotyped patients.

A novel mutation in the AGXT gene causing primary hyperoxaluria type I: genotype-phenotype correlation.

PubMed

M'Dimegh, Saoussen; Aquaviva-Bourdain, Cécile; Omezzine, Asma; M'Barek, Ibtihel; Souche, Geneviéve; Zellama, Dorsaf; Abidi, Kamel; Achour, Abdelattif; Gargah, Tahar; Abroug, Saoussen; Bouslama, Ali

2016-09-01

Primary hyperoxaluria type I (PH1) is an autosomal recessive metabolic disorder caused by inherited mutations in the AGXT gene encoding liver peroxisomal alanine : glyoxylate aminotransferase (AGT) which is deficient or mistargeted to mitochondria. PH1 shows considerable phenotypic and genotypic heterogeneity. The incidence and severity of PH1 varies in different geographic regions. DNA samples of the affected members from two unrelated Tunisian families were tested by amplifying and sequencing each of the AGXT exons and intron-exon junctions. We identified a novel frameshift mutation in the AGXT gene, the c.406_410dupACTGC resulting in a truncated protein (p.Gln137Hisfs*19). It is found in homozygous state in two nonconsanguineous unrelated families from Tunisia. These molecular findings provide genotype/phenotype correlations in the intrafamilial phenotypic and permit accurate carrier detection, and prenatal diagnosis. The novel p.Gln137Hisfs*19 mutation detected in our study extend the spectrum of known AGXT gene mutations in Tunisia.

Lessons from Cuba for Global Precision Medicine: CYP2D6 Genotype Is Not a Robust Predictor of CYP2D6 Ultrarapid Metabolism.

PubMed

Dorado, Pedro; González, Idilio; Naranjo, María Eugenia G; de Andrés, Fernando; Peñas-Lledó, Eva María; Calzadilla, Luis Ramón; LLerena, Adrián

2017-01-01

A long-standing question and dilemma in precision medicine is whether and to what extent genotyping or phenotyping drug metabolizing enzymes such as CYP2D6 can be used in real-life global clinical and societal settings. Although in an ideal world using both genotype and phenotype biomarkers are desirable, this is not always feasible for economic and practical reasons. Moreover, an additional barrier for clinical implementation of precision medicine is the lack of correlation between genotype and phenotype, considering that most of the current methods include only genotyping. Thus, the present study evaluated, using dextromethorphan as a phenotyping probe, the relationship between CYP2D6 phenotype and CYP2D6 genotype, especially for the ultrarapid metabolizer (UM) phenotype. We report in this study, to the best of our knowledge, the first comparative clinical pharmacogenomics study in a Cuban population sample (N = 174 healthy volunteers) and show that the CYP2D6 genotype is not a robust predictor of the CYP2D6 ultrarapid metabolizer (mUM) status in Cubans. Importantly, the ultrarapid CYP2D6 phenotype can result in a host of health outcomes, such as drug resistance associated with subtherapeutic drug concentrations, overexposure to active drug metabolites, and altered sensitivity to certain human diseases by virtue of altered metabolism of endogenous substrates of CYP2D6. Hence, phenotyping tests for CYP2D6 UMs appear to be a particular necessity for precision medicine in the Cuban population. Finally, in consideration of ethical and inclusive representation in global science, we recommend further precision medicine biomarker research and funding in support of neglected or understudied populations worldwide.

[Phenotype-genotype correlation analysis of 12 cases with Angelman/Prader-Willi syndrome].

PubMed

Chen, Chen; Peng, Ying; Xia, Yan; Li, Haoxian; Zhu, Huimin; Pan, Qian; Yin, Fei; Wu, Lingqian

2014-12-01

To investigate the genotype-phenotype correlation in patients with Angelman syndrome/Prader-Willi syndrome (AS/PWS) and assess the application value of high-resolution single nucleotide polymorphism microarrays (SNP array) for such diseases. Twelve AS/PWS patients were diagnosed through SNP array, fluorescence in situ hybridization (FISH) and karyotype analysis. Clinical characteristics were analyzed. Deletions ranging from 4.8 Mb to 7.0 Mb on chromosome 15q11.2-13 were detected in 11 patients. Uniparental disomy (UPD) was detected in only 1 patient. Patients with deletions could be divided into 2 groups, including 7 cases with class I and 4 with class II. The two groups however had no significant phenotypic difference. The UPD patient had relatively better development and language ability. Deletions of 6 patients were confirmed by FISH to be of de novo in origin. The risk to their sibs was determined to be less than 1%. The phenotypic differences between AS/PWS patients with class I and class II deletion need to be further studied. SNP array is useful in detecting and distinguishing of patients with deletion or UPD. This method may be applied for studying the genotype-phenotype association and the mechanism underlying AS/PWS.

Whole-Blood Thiopurine S-Methyltransferase Genotype and Phenotype Concordance in Iranian Kurdish Ulcerative Colitis (UC) Patients.

PubMed

Bahrehmand, Fariborz; Vaisi-Raygani, Asad; Kiani, Amir; Bashiri, Homayoun; Zobeiri, Mahdi; Tanhapour, Maryam; Pourmotabbed, Tayebeh

2017-05-01

Thiopurine methyl transferase (TPMT), a drug-metabolizing enzyme, catalyzes methylation and consequently, the metabolism of thiopurine compounds used for treatment of inflammatory bowel disease (IBD). Individuals who are homozygous recessive or have extremely low TPMT activity need to avoid thiopurines because of concern for significant leukopenia. The aim of this research was to determine TPMT phenotypes and genotypes in IBD patients to predict the risk of thiopurine toxicity before treatment. The present case-control study consisted of 210 ulcerative colitis patients and 212 unrelated healthy controls from the population of western Iran. TPMT phenotype and genotype were determined by HPLC and allele specific PCR and PCR-RFLP, respectively. TPMT phenotyping and genotyping were compatible and demonstrated no frequency for deficient, 2.2% for low, and 97.8% for normal-activity which is different compared with the results of other studies. There was a significant negative correlation between TPMT activities as calculated based on nmol6MTG/gHb/h and the Hb levels in both UC (r = -0.54, p < 0.001) and control groups (r = -0.27, p < 0.001). Interestingly, a significant positive correlation between Hb levels and TPMT activities was seen when the enzyme activity was calculated in mU/L in both UC patients (r = 0.14, p = 0.05) and in control subjects (r = 0.43, p < 0.001). The overall concordance rate between TPMT phenotypes and genotypes of mutants to alleles (9 out of 422), based on receiver-operating characteristic (ROC) curve, yielded a sensitivity of 94.7% and specificity of 90% for mU/L and a sensitivity of 85.6% and specificity of 90% for nmol6MTG/gHb/h. The use of mU/L is more appropriate than nmol6MTG/gHb/h for expressing TPMT activity, and there is better correlation between genotypes and phenotypes of TPMT based on mU/L. The frequency of known mutant TPMT alleles in western Iran (Kurd population) is low suggesting low risk of thiopurine drug toxicity in IBD patients from this region.

Complex inheritance in Pulmonary Arterial Hypertension patients with several mutations

PubMed Central

Pousada, Guillermo; Baloira, Adolfo; Valverde, Diana

2016-01-01

Pulmonary Arterial Hypertension (PAH) is a rare and progressive disease with low incidence and prevalence, and elevated mortality. PAH is characterized by increased mean pulmonary artery pressure. The aim of this study was to analyse patients with combined mutations in BMPR2, ACVRL1, ENG and KCNA5 genes and to establish a genotype-phenotype correlation. Major genes were analysed by polymerase chain reaction (PCR) and direct sequencing. Genotype-phenotype correlation was performed. Fifty-seven (28 idiopathic PAH, 29 associated PAH group I) were included. Several mutations in different genes, classified as pathogenic by in silico analysis, were present in 26% of PAH patients. The most commonly involved gene was BMPR2 (12 patients) followed by ENG gene (9 patients). ACVRL1 and KCNA5 genes showed very low incidence of mutations (5 and 1 patients, respectively). Genotype-phenotype correlation showed statistically significant differences for gender (p = 0.045), age at diagnosis (p = 0.035), pulmonary vascular resistance (p = 0.030), cardiac index (p = 0.035) and absence of response to treatment (p = 0.011). PAH is consequence of a heterogeneous constellation of genetic arrangements. Patients with several pathogenic mutations seem to display a more severe phenotype. PMID:27630060

Truncating mutations of HIBCH tend to cause severe phenotypes in cases with HIBCH deficiency: a case report and brief literature review.

PubMed

Tan, Hu; Chen, Xin; Lv, Weigang; Linpeng, Siyuan; Liang, Desheng; Wu, Lingqian

2018-04-27

3-hydroxyisobutryl-CoA hydrolase (HIBCH) deficiency is a rare inborn error of valine metabolism characterized by neurodegenerative symptoms and caused by recessive mutations in the HIBCH gene. In this study, utilizing whole exome sequencing, we identified two novel splicing mutations of HIBCH (c.304+3A>G; c.1010_1011+3delTGGTA) in a Chinese patient with characterized neurodegenerative features of HIBCH deficiency and bilateral syndactyly which was not reported in previous studies. Functional tests showed that both of these two mutations destroyed the normal splicing and reduced the expression of HIBCH protein. Through a literature review, a potential phenotype-genotype correlation was found that patients carrying truncating mutations tended to have more severe phenotypes compared with those with missense mutations. Our findings would widen the mutation spectrum of HIBCH causing HIBCH deficiency and the phenotypic spectrum of the disease. The potential genotype-phenotype correlation would be profitable for the treatment and management of patients with HIBCH deficiency.

SigniSite: Identification of residue-level genotype-phenotype correlations in protein multiple sequence alignments.

PubMed

Jessen, Leon Eyrich; Hoof, Ilka; Lund, Ole; Nielsen, Morten

2013-07-01

Identifying which mutation(s) within a given genotype is responsible for an observable phenotype is important in many aspects of molecular biology. Here, we present SigniSite, an online application for subgroup-free residue-level genotype-phenotype correlation. In contrast to similar methods, SigniSite does not require any pre-definition of subgroups or binary classification. Input is a set of protein sequences where each sequence has an associated real number, quantifying a given phenotype. SigniSite will then identify which amino acid residues are significantly associated with the data set phenotype. As output, SigniSite displays a sequence logo, depicting the strength of the phenotype association of each residue and a heat-map identifying 'hot' or 'cold' regions. SigniSite was benchmarked against SPEER, a state-of-the-art method for the prediction of specificity determining positions (SDP) using a set of human immunodeficiency virus protease-inhibitor genotype-phenotype data and corresponding resistance mutation scores from the Stanford University HIV Drug Resistance Database, and a data set of protein families with experimentally annotated SDPs. For both data sets, SigniSite was found to outperform SPEER. SigniSite is available at: http://www.cbs.dtu.dk/services/SigniSite/.

Soil coring at multiple field environments can directly quantify variation in deep root traits to select wheat genotypes for breeding.

PubMed

Wasson, A P; Rebetzke, G J; Kirkegaard, J A; Christopher, J; Richards, R A; Watt, M

2014-11-01

We aim to incorporate deep root traits into future wheat varieties to increase access to stored soil water during grain development, which is twice as valuable for yield as water captured at younger stages. Most root phenotyping efforts have been indirect studies in the laboratory, at young plant stages, or using indirect shoot measures. Here, soil coring to 2 m depth was used across three field environments to directly phenotype deep root traits on grain development (depth, descent rate, density, length, and distribution). Shoot phenotypes at coring included canopy temperature depression, chlorophyll reflectance, and green leaf scoring, with developmental stage, biomass, and yield. Current varieties, and genotypes with breeding histories and plant architectures expected to promote deep roots, were used to maximize identification of variation due to genetics. Variation was observed for deep root traits (e.g. 111.4-178.5cm (60%) for depth; 0.09-0.22cm/°C day (144%) for descent rate) using soil coring in the field environments. There was significant variation for root traits between sites, and variation in the relative performance of genotypes between sites. However, genotypes were identified that performed consistently well or poorly at both sites. Furthermore, high-performing genotypes were statistically superior in root traits than low-performing genotypes or commercial varieties. There was a weak but significant negative correlation between green leaf score (-0.5), CTD (0.45), and rooting depth and a positive correlation for chlorophyll reflectance (0.32). Shoot phenotypes did not predict other root traits. This study suggests that field coring can directly identify variation in deep root traits to speed up selection of genotypes for breeding programmes. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Face shape differs in phylogenetically related populations.

PubMed

Hopman, Saskia M J; Merks, Johannes H M; Suttie, Michael; Hennekam, Raoul C M; Hammond, Peter

2014-11-01

3D analysis of facial morphology has delineated facial phenotypes in many medical conditions and detected fine grained differences between typical and atypical patients to inform genotype-phenotype studies. Next-generation sequencing techniques have enabled extremely detailed genotype-phenotype correlative analysis. Such comparisons typically employ control groups matched for age, sex and ethnicity and the distinction between ethnic categories in genotype-phenotype studies has been widely debated. The phylogenetic tree based on genetic polymorphism studies divides the world population into nine subpopulations. Here we show statistically significant face shape differences between two European Caucasian populations of close phylogenetic and geographic proximity from the UK and The Netherlands. The average face shape differences between the Dutch and UK cohorts were visualised in dynamic morphs and signature heat maps, and quantified for their statistical significance using both conventional anthropometry and state of the art dense surface modelling techniques. Our results demonstrate significant differences between Dutch and UK face shape. Other studies have shown that genetic variants influence normal facial variation. Thus, face shape difference between populations could reflect underlying genetic difference. This should be taken into account in genotype-phenotype studies and we recommend that in those studies reference groups be established in the same population as the individuals who form the subject of the study.

Is there a genotype-phenotype correlation in primary hyperoxaluria type 1?

PubMed

Beck, B B; Hoppe, B

2006-09-01

There is ongoing debate about a genotype-phenotype correlation in patients with primary hyperoxaluria type 1 and specific AGXT mutations. However, other determinants like environmental factors or modifer genes may play a pivotal role in the heterogeneity of the disease. The report of Lorenzo and co-workers highlights this situation, presenting data of a whole population with just one specific AGXT mutation.

Duchenne Muscular Dystrophy and Becker Muscular Dystrophy Confirmed by Multiplex Ligation-Dependent Probe Amplification: Genotype-Phenotype Correlation in a Large Cohort.

PubMed

Vengalil, Seena; Preethish-Kumar, Veeramani; Polavarapu, Kiran; Mahadevappa, Manjunath; Sekar, Deepha; Purushottam, Meera; Thomas, Priya Treesa; Nashi, Saraswathi; Nalini, Atchayaram

2017-01-01

Studies of cases of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) confirmed by multiplex ligation-dependent probe amplification (MLPA) have determined the clinical characteristics, genotype, and relations between the reading frame and phenotype for different countries. This is the first such study from India. A retrospective genotype-phenotype analysis of 317 MLPA-confirmed patients with DMD or BMD who visited the neuromuscular clinic of a quaternary referral center in southern India. The 317 patients comprised 279 cases of DMD (88%), 32 of BMD (10.1%), and 6 of intermediate phenotype (1.9%). Deletions accounted for 91.8% of cases, with duplications causing the remaining 8.2%. There were 254 cases of DMD (91%) with deletions and 25 (9%) due to duplications, and 31 cases (96.8%) of BMD with deletions and 1 (3.2%) due to duplication. All six cases of intermediate type were due to deletions. The most-common mutation was a single-exon deletion. Deletions of six or fewer exons constituted 68.8% of cases. The deletion of exon 50 was the most common. The reading-frame rule held in 90% of DMD and 94% of BMD cases. A tendency toward a lower IQ and earlier wheelchair dependence was observed with distal exon deletions, though a significant correlation was not found. The reading-frame rule held in 90% to 94% of children, which is consistent with reports from other parts of the world. However, testing by MLPA is a limitation, and advanced sequencing methods including analysis of the structure of mutant dystrophin is needed for more-accurate assessments of the genotype-phenotype correlation.

Novel mutations and their genotype-phenotype correlations in patients with Noonan syndrome, using next-generation sequencing.

PubMed

Tafazoli, Alireza; Eshraghi, Peyman; Pantaleoni, Francesca; Vakili, Rahim; Moghaddassian, Morteza; Ghahraman, Martha; Muto, Valentina; Paolacci, Stefano; Golyan, Fatemeh Fardi; Abbaszadegan, Mohammad Reza

2018-03-01

Noonan Syndrome (NS) is an autosomal dominant disorder with many variable and heterogeneous conditions. The genetic basis for 20-30% of cases is still unknown. This study evaluates Iranian Noonan patients both clinically and genetically for the first time. Mutational analysis of PTPN11 gene was performed in 15 Iranian patients, using PCR and Sanger sequencing at phase one. Then, as phase two, Next Generation Sequencing (NGS) in the form of targeted resequencing was utilized for analysis of exons from other related genes. Homology modelling for the novel founded mutations was performed as well. The genotype, phenotype correlation was done according to the molecular findings and clinical features. Previously reported mutation (p.N308D) in some patients and a novel mutation (p.D155N) in one of the patients were identified in phase one. After applying NGS methods, known and new variants were found in four patients in other genes, including: CBL (p. V904I), KRAS (p. L53W), SOS1 (p. I1302V), and SOS1 (p. R552G). Structural studies of two deduced novel mutations in related genes revealed deficiencies in the mutated proteins. Following genotype, phenotype correlation, a new pattern of the presence of intellectual disability in two patients was registered. NS shows strong variable expressivity along the high genetic heterogeneity especially in distinct populations and ethnic groups. Also possibly unknown other causative genes may be exist. Obviously, more comprehensive and new technologies like NGS methods are the best choice for detection of molecular defects in patients for genotype, phenotype correlation and disease management. Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.

Genotype-phenotype correlation in boys with X-linked hypohidrotic ectodermal dysplasia.

PubMed

Burger, Kristin; Schneider, Anne-Theres; Wohlfart, Sigrun; Kiesewetter, Franklin; Huttner, Kenneth; Johnson, Ramsey; Schneider, Holm

2014-10-01

X-linked hypohidrotic ectodermal dysplasia (XLHED), the most frequent form of ectodermal dysplasia, is a genetic disorder of ectoderm development characterized by malformation of multiple ectodermal structures such as skin, hair, sweat and sebaceous glands, and teeth. The disease is caused by a broad spectrum of mutations in the gene EDA. Although XLHED symptoms show inter-familial and intra-familial variability, genotype-phenotype correlation has been demonstrated with respect to sweat gland function. In this study, we investigated to which extent the EDA genotype correlates with the severity of XLHED-related skin and hair signs. Nineteen male children with XLHED (age range 3-14 years) and seven controls (aged 6-14 years) were examined by confocal microscopy of the skin, quantification of pilocarpine-induced sweating, semi-quantitative evaluation of full facial photographs with respect to XLHED-related skin issues, and phototrichogram analysis. All eight boys with known hypomorphic EDA mutations were able to produce at least some sweat and showed less severe cutaneous signs of XLHED than the anhidrotic XLHED patients (e.g., perioral and periorbital eczema or hyperpigmentation, regional hyperkeratosis, characteristic wrinkles under the eyes). As expected, individuals with XLHED had significantly less and thinner hair than healthy controls. However, there were also significant differences in hair number, diameter, and other hair characteristics between the group with hypomorphic EDA mutations and the anhidrotic patients. In summary, this study indicated a remarkable genotype-phenotype correlation of skin and hair findings in prepubescent males with XLHED. © 2014 Wiley Periodicals, Inc.

Evaluation of the genotypic prediction of HIV-1 coreceptor use versus a phenotypic assay and correlation with the virological response to maraviroc: the ANRS GenoTropism study.

PubMed

Recordon-Pinson, Patricia; Soulié, Cathia; Flandre, Philippe; Descamps, Diane; Lazrek, Mouna; Charpentier, Charlotte; Montes, Brigitte; Trabaud, Mary-Anne; Cottalorda, Jacqueline; Schneider, Véronique; Morand-Joubert, Laurence; Tamalet, Catherine; Desbois, Delphine; Macé, Muriel; Ferré, Virginie; Vabret, Astrid; Ruffault, Annick; Pallier, Coralie; Raymond, Stéphanie; Izopet, Jacques; Reynes, Jacques; Marcelin, Anne-Geneviève; Masquelier, Bernard

2010-08-01

Genotypic algorithms for prediction of HIV-1 coreceptor usage need to be evaluated in a clinical setting. We aimed at studying (i) the correlation of genotypic prediction of coreceptor use in comparison with a phenotypic assay and (ii) the relationship between genotypic prediction of coreceptor use at baseline and the virological response (VR) to a therapy including maraviroc (MVC). Antiretroviral-experienced patients were included in the MVC Expanded Access Program if they had an R5 screening result with Trofile (Monogram Biosciences). V3 loop sequences were determined at screening, and coreceptor use was predicted using 13 genotypic algorithms or combinations of algorithms. Genotypic predictions were compared to Trofile; dual or mixed (D/M) variants were considered as X4 variants. Both genotypic and phenotypic results were obtained for 189 patients at screening, with 54 isolates scored as X4 or D/M and 135 scored as R5 with Trofile. The highest sensitivity (59.3%) for detection of X4 was obtained with the Geno2pheno algorithm, with a false-positive rate set up at 10% (Geno2pheno10). In the 112 patients receiving MVC, a plasma viral RNA load of <50 copies/ml was obtained in 68% of cases at month 6. In multivariate analysis, the prediction of the X4 genotype at baseline with the Geno2pheno10 algorithm including baseline viral load and CD4 nadir was independently associated with a worse VR at months 1 and 3. The baseline weighted genotypic sensitivity score was associated with VR at month 6. There were strong arguments in favor of using genotypic coreceptor use assays for determining which patients would respond to CCR5 antagonist.

Phenotypic similarities and differences in patients with a p.Met112Ile mutation in SOX10.

PubMed

Pingault, Veronique; Pierre-Louis, Laurence; Chaoui, Asma; Verloes, Alain; Sarrazin, Elisabeth; Brandberg, Goran; Bondurand, Nadege; Uldall, Peter; Manouvrier-Hanu, Sylvie

2014-09-01

Waardenburg syndrome (WS) is characterized by an association of pigmentation abnormalities and sensorineural hearing loss. Four types, defined on clinical grounds, have been delineated, but this phenotypic classification correlates imperfectly with known molecular anomalies. SOX10 mutations have been found in patients with type II and type IV WS (i.e., with Hirschsprung disease), more complex syndromes, and partial forms of the disease. The phenotype induced by SOX10 mutations is highly variable and, except for the neurological forms of the disease, no genotype-phenotype correlation has been characterized to date. There is no mutation hotspot in SOX10 and most cases are sporadic, making it particularly difficult to correlate the phenotypic and genetic variability. This study reports on three independent families with SOX10 mutations predicted to result in the same missense mutation at the protein level (p.Met112Ile), offering a rare opportunity to improve our understanding of the mechanisms underlying phenotypic variability. The pigmentation defects of these patients are very similar, and the neurological symptoms showed a somewhat similar evolution over time, indicating a potential partial genotype-phenotype correlation. However, variability in gastrointestinal symptoms suggests that other genetic factors contribute to the expression of these phenotypes. No correlation between the rs2435357 polymorphism of RET and the expression of Hirschsprung disease was found. In addition, one of the patients has esophageal achalasia, which has rarely been described in WS. © 2014 Wiley Periodicals, Inc.

Phenotypic similarities and differences in patients with a p.Met112Ile mutation in SOX10

PubMed Central

Pingault, Veronique; Pierre-Louis, Laurence; Chaoui, Asma; Verloes, Alain; Sarrazin, Elisabeth; Brandberg, Goran; Bondurand, Nadege; Uldall, Peter; Manouvrier-Hanu, Sylvie

2014-01-01

Waardenburg syndrome (WS) is characterized by an association of pigmentation abnormalities and sensorineural hearing loss. Four types, defined on clinical grounds, have been delineated, but this phenotypic classification correlates imperfectly with known molecular anomalies. SOX10 mutations have been found in patients with type II and type IV WS (i.e., with Hirschsprung disease), more complex syndromes, and partial forms of the disease. The phenotype induced by SOX10 mutations is highly variable and, except for the neurological forms of the disease, no genotype-phenotype correlation has been characterized to date. There is no mutation hotspot in SOX10 and most cases are sporadic, making it particularly difficult to correlate the phenotypic and genetic variability. This study reports on three independent families with SOX10 mutations predicted to result in the same missense mutation at the protein level (p.Met112Ile), offering a rare opportunity to improve our understanding of the mechanisms underlying phenotypic variability. The pigmentation defects of these patients are very similar, and the neurological symptoms showed a somewhat similar evolution over time, indicating a potential partial genotype-phenotype correlation. However, variability in gastrointestinal symptoms suggests that other genetic factors contribute to the expression of these phenotypes. No correlation between the rs2435357 polymorphism of RET and the expression of Hirschsprung disease was found. In addition, one of the patients has esophageal achalasia, which has rarely been described in WS. PMID:24845202

Pseudomonas aeruginosa in Dairy Goats: Genotypic and Phenotypic Comparison of Intramammary and Environmental Isolates

PubMed Central

Scaccabarozzi, Licia; Leoni, Livia; Ballarini, Annalisa; Barberio, Antonio; Locatelli, Clara; Casula, Antonio; Bronzo, Valerio; Pisoni, Giuliano; Jousson, Olivier; Morandi, Stefano; Rapetti, Luca; García-Fernández, Aurora; Moroni, Paolo

2015-01-01

Following the identification of a case of severe clinical mastitis in a Saanen dairy goat (goat A), an average of 26 lactating goats in the herd was monitored over a period of 11 months. Milk microbiological analysis revealed the presence of Pseudomonas aeruginosa in 7 of the goats. Among these 7 does, only goat A showed clinical signs of mastitis. The 7 P. aeruginosa isolates from the goat milk and 26 P. aeruginosa isolates from environmental samples were clustered by RAPD-PCR and PFGE analyses in 3 genotypes (G1, G2, G3) and 4 clusters (A, B, C, D), respectively. PFGE clusters A and B correlated with the G1 genotype and included the 7 milk isolates. Although it was not possible to identify the infection source, these results strongly suggest a spreading of the infection from goat A. Clusters C and D overlapped with genotypes G2 and G3, respectively, and included only environmental isolates. The outcome of the antimicrobial susceptibility test performed on the isolates revealed 2 main patterns of multiple resistance to beta-lactam antibiotics and macrolides. Virulence related phenotypes were analyzed, such as swarming and swimming motility, production of biofilm and production of secreted virulence factors. The isolates had distinct phenotypic profiles, corresponding to genotypes G1, G2 and G3. Overall, correlation analysis showed a strong correlation between sampling source, RAPD genotype, PFGE clusters, and phenotypic clusters. The comparison of the levels of virulence related phenotypes did not indicate a higher pathogenic potential in the milk isolates as compared to the environmental isolates. PMID:26606430

Hb Adana (HBA2 or HBA1: c.179G > A) and alpha thalassemia: Genotype-phenotype correlation.

PubMed

Singh, Sharon A; Sarangi, Susmita; Appiah-Kubi, Abena; Hsu, Peihong; Smith, W Byron; Gallagher, Patrick G; Glader, Bertil; Chui, David H K

2018-05-11

Alpha thalassemia due to nondeletional mutations usually leads to more severe disease than that caused by deletional mutations. Devastating outcomes such as hydrops fetalis can occur with two nondeletional mutations, therefore warranting DNA-based workup for suspected carriers with subtle hematological abnormalities for family counseling purposes. We describe three cases with hemoglobin (Hb) Adana, a nondeletional alpha chain mutation, compounded with an alpha globin gene deletion resulting in thalassemia intermedia. We review the literature, draw genotype-phenotype correlations from published cases of Hb Adana, and propose that this correlation can be used by clinicians to help direct diagnostic studies and urge hematologists to thoroughly workup high-risk patients. © 2018 Wiley Periodicals, Inc.

The Discriminatory Value of CYP2D6 Genotyping in Predicting the Dextromethorphan/Dextrorphan Phenotype in Women with Breast Cancer

PubMed Central

Trojan, Andreas; Vergopoulos, Athanasios; Breitenstein, Urs; Seifert, Burkhardt; Rageth, Christoph; Joechle, Wolfgang

2012-01-01

Background The growth inhibitory effect of tamoxifen is used for the treatment of breast cancer. Tamoxifen efficacy is mediated by its biotransformation, predominantly via the cytochrome P450 2D6 (CYP2D6) isoenzyme, to the active metabolite endoxifen. We investigated the relationship of CYP2D6 genotypes to the metabolism of dextromethorphan (DM), which is frequently used as a surrogate marker for the formation of endoxifen. Methods The CYP2D6 genotype was determined by polymerase chain reaction (PCR) in previously untreated patients with hormone receptor-positive invasive breast cancer considered to receive antihormonal therapy. The DM/dextrorphan (DX) urinary excretion ratios were obtained in a subset of patients by high-pressure liquid chromatography (HPLC)-mediated urine analysis after intake of 25 mg DM. The relationships of genotype and corresponding phenotype were statistically analyzed for association. Results From 151 patients predicted based on their genotype data for the ‘traditional’ CYP2D6 phenotype classes poor, intermediate, extensive and ultrarapid, 83 patients were examined for their DM/DX urinary ratios. The genotype-based poor metabolizer status correlated with the DM/DX ratios, whereas the intermediate, extensive and ultrarapid genotypes could not be distinguished based on their phenotype. Citalopram intake did not significantly influence the phenotype. Conclusions The DM metabolism can be reliably used to assess the CYP2D6 enzyme activity. The correlation with the genotype can be incomplete and the metabolic ratios do not seem to be compromised by citalopram. DM phenotyping may provide a standardized tool to better assess the CYP2D6 metabolic capacity. PMID:22553469

A deletion and a duplication in distal 22q11.2 deletion syndrome region. Clinical implications and review

PubMed Central

Fernández, Luis; Nevado, Julián; Santos, Fernando; Heine-Suñer, Damià; Martinez-Glez, Victor; García-Miñaur, Sixto; Palomo, Rebeca; Delicado, Alicia; Pajares, Isidora López; Palomares, María; García-Guereta, Luis; Valverde, Eva; Hawkins, Federico; Lapunzina, Pablo

2009-01-01

Background Individuals affected with DiGeorge and Velocardiofacial syndromes present with both phenotypic diversity and variable expressivity. The most frequent clinical features include conotruncal congenital heart defects, velopharyngeal insufficiency, hypocalcemia and a characteristic craniofacial dysmorphism. The etiology in most patients is a 3 Mb recurrent deletion in region 22q11.2. However, cases of infrequent deletions and duplications with different sizes and locations have also been reported, generally with a milder, slightly different phenotype for duplications but with no clear genotype-phenotype correlation to date. Methods We present a 7 month-old male patient with surgically corrected ASD and multiple VSDs, and dysmorphic facial features not clearly suggestive of 22q11.2 deletion syndrome, and a newborn male infant with cleft lip and palate and upslanting palpebral fissures. Karyotype, FISH, MLPA, microsatellite markers segregation studies and SNP genotyping by array-CGH were performed in both patients and parents. Results Karyotype and FISH with probe N25 were normal for both patients. MLPA analysis detected a partial de novo 1.1 Mb deletion in one patient and a novel partial familial 0.4 Mb duplication in the other. Both of these alterations were located at a distal position within the commonly deleted region in 22q11.2. These rearrangements were confirmed and accurately characterized by microsatellite marker segregation studies and SNP array genotyping. Conclusion The phenotypic diversity found for deletions and duplications supports a lack of genotype-phenotype correlation in the vicinity of the LCRC-LCRD interval of the 22q11.2 chromosomal region, whereas the high presence of duplications in normal individuals supports their role as polymorphisms. We suggest that any hypothetical correlation between the clinical phenotype and the size and location of these alterations may be masked by other genetic and/or epigenetic modifying factors. PMID:19490635

Brain imaging in mitochondrial respiratory chain deficiency: combination of brain MRI features as a useful tool for genotype/phenotype correlations.

PubMed

Bricout, M; Grévent, D; Lebre, A S; Rio, M; Desguerre, I; De Lonlay, P; Valayannopoulos, V; Brunelle, F; Rötig, A; Munnich, A; Boddaert, N

2014-07-01

Mitochondrial diseases are characterised by a broad clinical and genetic heterogeneity that makes diagnosis difficult. Owing to the wide pattern of symptoms in mitochondrial disorders and the constantly growing number of disease genes, their genetic diagnosis is difficult and genotype/phenotype correlations remain elusive. Brain MRI appears as a useful tool for genotype/phenotype correlations. Here, we summarise the various combinations of MRI lesions observed in the most frequent mitochondrial respiratory chain deficiencies so as to direct molecular genetic test in patients at risk of such diseases. We believe that the combination of brain MRI features is of value to support respiratory chain deficiency and direct molecular genetic tests. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Paranormal experience and the COMT dopaminergic gene: a preliminary attempt to associate phenotype with genotype using an underlying brain theory.

PubMed

Raz, Amir; Hines, Terence; Fossella, John; Castro, Daniella

2008-01-01

Paranormal belief and suggestibility seem related. Given our recent findings outlining a putative association between suggestibility and a specific dopaminergic genetic polymorphism, we hypothesized that similar exploratory genetic data may offer supplementary insights into a similar correlation with paranormal belief. With more affordable costs and better technology in the aftermath of the human genome project, genotyping is increasingly ubiquitous. Compelling brain theories guide specific research hypotheses as scientists begin to unravel tentative relationships between phenotype and genotype. In line with a dopaminergic brain theory, we tried to correlate a specific phenotype concerning paranormal belief with a dopaminergic gene (COMT) known for its involvement in prefrontal executive cognition and for a polymorphism that is positively correlated with suggestibility. Although our preliminary findings are inconclusive, the research approach we outline should pave the road to a more scientific account of elucidating paranormal belief.

Neurophysiology versus clinical genetics in Rett syndrome: A multicenter study.

PubMed

Halbach, Nicky; Smeets, Eric E; Julu, Peter; Witt-Engerström, Ingegerd; Pini, Giorgio; Bigoni, Stefania; Hansen, Stig; Apartopoulos, Flora; Delamont, Robert; van Roozendaal, Kees; Scusa, Maria F; Borelli, Paolo; Candel, Math; Curfs, Leopold

2016-09-01

Many studies have attempted to establish the genotype-phenotype correlation in Rett syndrome (RTT). Cardiorespiratory measurements provide robust objective data, to correlate with each of the different clinical phenotypes. It has important implications for the management and treatment of this syndrome. The aim of this study was to correlate the genotype with the quantitative cardiorespiratory data obtained by neurophysiological measurement combined with a clinical severity score. This international multicenter study was conducted in four European countries from 1999 to 2012. The study cohort consisted of a group of 132 well-defined RTT females aged between 2 and 43 years with extended clinical, molecular, and neurophysiological assessments. Diagnosis of RTT was based on the consensus criteria for RTT and molecular confirmation. Genotype-phenotype analyses of clinical features and cardiorespiratory data were performed after grouping mutations by the same type and localization or having the same putative biological effect on the MeCP2 protein, and subsequently on eight single recurrent mutations. A less severe phenotype was seen in females with CTS, p.R133C, and p.R294X mutations. Autonomic disturbances were present in all females, and not restricted to nor influenced by one specific group or any single recurrent mutation. The objective information from non-invasive neurophysiological evaluation of the disturbed central autonomic control is of great importance in helping to organize the lifelong care for females with RTT. Further research is needed to provide insights into the pathogenesis of autonomic dysfunction, and to develop evidence-based management in RTT. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis.

PubMed

Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

2016-07-01

A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness.Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Code is available at https://github.com/aalto-ics-kepaco anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis

PubMed Central

Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J.; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T.; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

2016-01-01

Motivation: A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. Results: We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness. Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Availability and implementation: Code is available at https://github.com/aalto-ics-kepaco Contacts: anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27153689

Retrospective genotype-phenotype analysis in a 305 patient cohort referred for testing of a targeted epilepsy panel.

PubMed

Hesse, Andrew N; Bevilacqua, Jennifer; Shankar, Kritika; Reddi, Honey V

2018-05-16

Epilepsy is a diverse neurological condition with extreme genetic and phenotypic heterogeneity. The introduction of next-generation sequencing into the clinical laboratory has made it possible to investigate hundreds of associated genes simultaneously for a patient, even in the absence of a clearly defined syndrome. This has resulted in the detection of rare and novel mutations at a rate well beyond our ability to characterize their effects. This retrospective study reviews genotype data in the context of available phenotypic information on 305 patients spanning the epileptic spectrum to identify established and novel patterns of correlation. Our epilepsy panel comprising 377 genes was used to sequence 305 patients referred for genetic testing. Qualifying variants were annotated with phenotypic data obtained from either the test requisition form or supporting clinical documentation. Observed phenotypes were compared with established phenotypes in OMIM, published literature and the ILAEs 2010 report on genetic testing to assess congruity with known gene aberrations. We identified a number of novel and recognized genetic variants consistent with established epileptic phenotypes. Forty-one pathogenic or predicted deleterious variants were detected in 39 patients with accompanying clinical documentation. Twenty-five of these variants across 15 genes were novel. Furthermore, evaluation of phenotype data for 194 patients with variants of unknown significance in genes with autosomal dominant and X-linked disease inheritance elucidated potentially disease-causing variants that were not currently characterized in the literature. Assessment of key genotype-phenotype correlations from our cohort provide insight into variant classification, as well as the importance of including ILAE recommended genes as part of minimum panel content for comprehensive epilepsy tests. Many of the reported VUSs are likely genuine pathogenic variants driving the observed phenotypes, but not enough evidence is available for assertive classifications. Similar studies will provide more utility via mounting independent genotype-phenotype data from unrelated patients. The possible outcome would be a better molecular diagnostic product, with fewer indeterminate reports containing only VUSs. Copyright © 2018. Published by Elsevier B.V.

Correlation of Lactobacillus rhamnosus Genotypes and Carbohydrate Utilization Signatures Determined by Phenotype Profiling

PubMed Central

Lambert, Jolanda; van Limpt, Kees; Wels, Michiel; Smokvina, Tamara; Knol, Jan; Kleerebezem, Michiel

2015-01-01

Lactobacillus rhamnosus is a bacterial species commonly colonizing the gastrointestinal (GI) tract of humans and also frequently used in food products. While some strains have been studied extensively, physiological variability among isolates of the species found in healthy humans or their diet is largely unexplored. The aim of this study was to characterize the diversity of carbohydrate utilization capabilities of human isolates and food-derived strains of L. rhamnosus in relation to their niche of isolation and genotype. We investigated the genotypic and phenotypic diversity of 25 out of 65 L. rhamnosus strains from various niches, mainly human feces and fermented dairy products. Genetic fingerprinting of the strains by amplified fragment length polymorphism (AFLP) identified 11 distinct subgroups at 70% similarity and suggested niche enrichment within particular genetic clades. High-resolution carbohydrate utilization profiling (OmniLog) identified 14 carbon sources that could be used by all of the strains tested for growth, while the utilization of 58 carbon sources differed significantly between strains, enabling the stratification of L. rhamnosus strains into three metabolic clusters that partially correlate with the genotypic clades but appear uncorrelated with the strain's origin of isolation. Draft genome sequences of 8 strains were generated and employed in a gene-trait matching (GTM) analysis together with the publicly available genomes of L. rhamnosus GG (ATCC 53103) and HN001 for several carbohydrates that were distinct for the different metabolic clusters: l-rhamnose, cellobiose, l-sorbose, and α-methyl-d-glucoside. From the analysis, candidate genes were identified that correlate with l-sorbose and α-methyl-d-glucoside utilization, and the proposed function of these genes could be confirmed by heterologous expression in a strain lacking the genes. This study expands our insight into the phenotypic and genotypic diversity of the species L. rhamnosus and explores the relationships between specific carbohydrate utilization capacities and genotype and/or niche adaptation of this species. PMID:26048937

Diagnostic Challenges in Retinitis Pigmentosa: Genotypic Multiplicity and Phenotypic Variability

PubMed Central

Chang, Susie; Vaccarella, Leah; Olatunji, Sunday; Cebulla, Colleen; Christoforidis, John

2011-01-01

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders. Diagnosis can be challenging as more than 40 genes are known to cause non-syndromic RP and phenotypic expression can differ significantly resulting in variations in disease severity, age of onset, rate of progression, and clinical findings. We describe the clinical manifestations of RP, the more commonly known causative gene mutations, and the genotypic-phenotypic correlation of RP. PMID:22131872

SCOPA and META-SCOPA: software for the analysis and aggregation of genome-wide association studies of multiple correlated phenotypes.

PubMed

Mägi, Reedik; Suleimanov, Yury V; Clarke, Geraldine M; Kaakinen, Marika; Fischer, Krista; Prokopenko, Inga; Morris, Andrew P

2017-01-11

Genome-wide association studies (GWAS) of single nucleotide polymorphisms (SNPs) have been successful in identifying loci contributing genetic effects to a wide range of complex human diseases and quantitative traits. The traditional approach to GWAS analysis is to consider each phenotype separately, despite the fact that many diseases and quantitative traits are correlated with each other, and often measured in the same sample of individuals. Multivariate analyses of correlated phenotypes have been demonstrated, by simulation, to increase power to detect association with SNPs, and thus may enable improved detection of novel loci contributing to diseases and quantitative traits. We have developed the SCOPA software to enable GWAS analysis of multiple correlated phenotypes. The software implements "reverse regression" methodology, which treats the genotype of an individual at a SNP as the outcome and the phenotypes as predictors in a general linear model. SCOPA can be applied to quantitative traits and categorical phenotypes, and can accommodate imputed genotypes under a dosage model. The accompanying META-SCOPA software enables meta-analysis of association summary statistics from SCOPA across GWAS. Application of SCOPA to two GWAS of high-and low-density lipoprotein cholesterol, triglycerides and body mass index, and subsequent meta-analysis with META-SCOPA, highlighted stronger association signals than univariate phenotype analysis at established lipid and obesity loci. The META-SCOPA meta-analysis also revealed a novel signal of association at genome-wide significance for triglycerides mapping to GPC5 (lead SNP rs71427535, p = 1.1x10 -8 ), which has not been reported in previous large-scale GWAS of lipid traits. The SCOPA and META-SCOPA software enable discovery and dissection of multiple phenotype association signals through implementation of a powerful reverse regression approach.

Dental management of amelogenesis imperfecta patients: a primer on genotype-phenotype correlations.

PubMed

Ng, F K; Messer, L B

2009-01-01

Amelogenesis imperfecta (AI) represents a group of hereditary conditions which affects enamel formation in the primary and permanent dentitions. Mutations in genes critical for amelogenesis result in diverse phenotypes characterized by variably thin and/or defective enamel. To date, mutations in 5 genes are known to cause AI in humans. Understanding the molecular etiologies and associated inheritance patterns can assist in the early diagnosis of this condition. Recognition of genotype-phenotype correlations will allow clinicians to guide genetic testing and select appropriate management strategies for patients who express different phenotypes. The purpose of this paper was to provide a narrative review of the current literature on amelogenesis imperfecta, particularly regarding recent advances in the identification of candidate genes and the patterns of inheritance.

Correspondence between the CYP2C19 and CYP3A4 genotypes with the inferred metabolizer phenotype by omeprazole administration in Mexican healthy children.

PubMed

Favela-Mendoza, A F; Martínez-Cortes, G; Romero-Prado, M M; Romero-Tejeda, E M; Islas-Carbajal, M C; Sosa-Macias, M; Lares-Asseff, I; Rangel-Villalobos, H

2018-05-07

CYP2C19 genotypes presumably allow the prediction of the metabolizer phenotypes: poor (PMs), extensive (EMs) and ultra-rapid (UMs). However, evidence from previous studies regarding this predictive power is unclear, which is important because the benefits expected by healthcare institutions and patients are based on this premise. Therefore, we aimed to complete a formal evaluation of the diagnostic value of CYP2C19 and CYP3A4 genes for predicting metabolizer phenotypes established by omeprazole (OME) administration in 118 healthy children from Jalisco (western Mexico). The genotypes for CYP3A4*1B and CYP2C19*2, *3, *4, *5 and *17 alleles were determined. CYP2C19 and CYP3A4 phenotypes were obtained after 20 mg OME administration and HPLC quantification in plasma to estimate the Hydroxylation Index (HI = OME/HOME) and Sulfonation Index (SI = OME/SOME), respectively. The distribution of genotypes and phenotypes for CYP2C19 and CYP3A4 was similar to previous studies in Mexico and Latin America. We estimated the CYP2C19 UM, EM and PM phenotype frequency in 0.84%, 96.61% and 2.54%, respectively. Although differences in the HI distribution were observed between CYP2C19 genotypes, they showed a poor diagnostic ability to predict the CYP2C19 metabolizer phenotype. Similarly, the number of CYP2C19 and CYP3A4 functional alleles was correlated with the HI distribution, but also their diagnostic ability to predict the CYP2C19 phenotype was poor. The CYP2C19 phenotype is not predicted by the number of functional alleles of CYP2C19 and CYP3A4 genes. Phenotyping is still the most valuable alternative to dose individualization for CYP2C19 substrate drugs. © 2018 John Wiley & Sons Ltd.

Cardio-facio-cutaneous syndrome: Does genotype predict phenotype?

PubMed Central

Allanson, Judith E; Annerén, Göran; Aoki, Yoki; Armour, Christine M; Bondeson, Marie-Louise; Cave, Helene; Gripp, Karen W; Kerr, Bronwyn; Nystrom, Anna-Maja; Sol-Church, Katia; Verloes, Alain; Zenker, Martin

2011-01-01

Cardio-facio-cutaneous syndrome is a sporadic multiple congenital anomalies/mental retardation condition principally caused by mutations in BRAF, MEK1, and MEK2. Mutations in KRAS and SHOC2 lead to a phenotype with overlapping features. In approximately 10–30% of individuals with a clinical diagnosis of cardio-facio-cutaneous, a mutation in one of these causative genes is not found. Cardinal features of cardio-facio-cutaneous include congenital heart defects, a characteristic facial appearance, and ectodermal abnormalities. Additional features include failure to thrive with severe feeding problems, moderate to severe intellectual disability and short stature with relative macrocephaly. First described in 1986, more than 100 affected individuals are reported. Following the discovery of the causative genes, more information has emerged on the breadth of clinical features. Little, however, has been published on genotype-phenotype correlations. This clinical study of 186 children and young adults with mutation-proven cardio-facio-cutaneous syndrome is the largest reported to date. BRAF mutations are documented in 140 individuals (~75%), while 46 (~25%) have a mutation in MEK 1 or MEK 2. The age range is 6 months to 32 years, the oldest individual being a female from the original report [Reynolds et al., 1986]. While some clinical data on 136 are in the literature, fifty are not previously published. We provide new details of the breadth of phenotype and discuss the frequency of particular features in each genotypic group. Pulmonary stenosis is the only anomaly that demonstrates a statistically significant genotype-phenotype correlation, being more common in individuals with a BRAF mutation. PMID:21495173

Evidence for an African cluster of human head and body lice with variable colors and interbreeding of lice between continents.

PubMed

Veracx, Aurélie; Boutellis, Amina; Merhej, Vicky; Diatta, Georges; Raoult, Didier

2012-01-01

Human head lice and body lice have been classified based on phenotypic characteristics, including geographical source, ecotype (preferred egg laying site hair or clothes), shape and color. More recently, genotypic studies have been based on mitochondrial genes, nuclear genes and intergenic spacers. Mitochondrial genetic analysis reclassified lice into three genotypes (A, B and C). However, no previous study has attempted to correlate both genotypic and phenotypic data. Lice were collected in four African countries: Senegal, Burundi, Rwanda and Ethiopia and were photographed to compare their colors. The Multi-Spacer-Typing (MST) method was used to genotype lice belonging to the worldwide Clade A, allowing a comparison of phenotypic and genotypic data. No congruence between louse color and genotype has been identified. Phylogenetic analysis of the spacer PM2, performed including lice from other sources, showed the existence of an African cluster of human lice. However, the analysis of other spacers suggested that lice from different areas are interbreeding. We identified two geotypes of Clade A head and body lice including one that is specifically African, that can be either black or grey and can live on the head or in clothing. We also hypothesized that lice from different areas are interbreeding.

A Genotypic-Oriented View of CFTR Genetics Highlights Specific Mutational Patterns Underlying Clinical Macrocategories of Cystic Fibrosis

PubMed Central

Lucarelli, Marco; Bruno, Sabina Maria; Pierandrei, Silvia; Ferraguti, Giampiero; Stamato, Antonella; Narzi, Fabiana; Amato, Annalisa; Cimino, Giuseppe; Bertasi, Serenella; Quattrucci, Serena; Strom, Roberto

2015-01-01

Cystic fibrosis (CF) is a monogenic disease caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The genotype–phenotype relationship in this disease is still unclear, and diagnostic, prognostic and therapeutic challenges persist. We enrolled 610 patients with different forms of CF and studied them from a clinical, biochemical, microbiological and genetic point of view. Overall, there were 125 different mutated alleles (11 with novel mutations and 10 with complex mutations) and 225 genotypes. A strong correlation between mutational patterns at the genotypic level and phenotypic macrocategories emerged. This specificity appears to largely depend on rare and individual mutations, as well as on the varying prevalence of common alleles in different clinical macrocategories. However, 19 genotypes appeared to underlie different clinical forms of the disease. The dissection of the pathway from the CFTR mutated genotype to the clinical phenotype allowed to identify at least two components of the variability usually found in the genotype–phenotype relationship. One component seems to depend on the genetic variation of CFTR, the other component on the cumulative effect of variations in other genes and cellular pathways independent from CFTR. The experimental dissection of the overall biological CFTR pathway appears to be a powerful approach for a better comprehension of the genotype–phenotype relationship. However, a change from an allele-oriented to a genotypic-oriented view of CFTR genetics is mandatory, as well as a better assessment of sources of variability within the CFTR pathway. PMID:25910067

The Monarch Initiative: an integrative data and analytic platform connecting phenotypes to genotypes across species

DOE PAGES

Mungall, Christopher J.; McMurry, Julie A.; Köhler, Sebastian; ...

2016-11-29

The correlation of phenotypic outcomes with genetic variation and environmental factors is a core pursuit in biology and biomedicine. Numerous challenges impede our progress: patient phenotypes may not match known diseases, candidate variants may be in genes that have not been characterized, model organisms may not recapitulate human or veterinary diseases, filling evolutionary gaps is difficult, and many resources must be queried to find potentially significant genotype-phenotype associations. Nonhuman organisms have proven instrumental in revealing biological mechanisms. Advanced informatics tools can identify phenotypically relevant disease models in research and diagnostic contexts. Large-scale integration of model organism and clinical research datamore » can provide a breadth of knowledge not available from individual sources and can provide contextualization of data back to these sources. The Monarch Initiative (monarchinitiative.org) is a collaborative, open science effort that aims to semantically integrate genotype-phenotype data from many species and sources in order to support precision medicine, disease modeling, and mechanistic exploration. Our integrated knowledge graph, analytic tools, and web services enable diverse users to explore relationships between phenotypes and genotypes across species.« less

Genotype-phenotype association study via new multi-task learning model

PubMed Central

Huo, Zhouyuan; Shen, Dinggang

2018-01-01

Research on the associations between genetic variations and imaging phenotypes is developing with the advance in high-throughput genotype and brain image techniques. Regression analysis of single nucleotide polymorphisms (SNPs) and imaging measures as quantitative traits (QTs) has been proposed to identify the quantitative trait loci (QTL) via multi-task learning models. Recent studies consider the interlinked structures within SNPs and imaging QTs through group lasso, e.g. ℓ2,1-norm, leading to better predictive results and insights of SNPs. However, group sparsity is not enough for representing the correlation between multiple tasks and ℓ2,1-norm regularization is not robust either. In this paper, we propose a new multi-task learning model to analyze the associations between SNPs and QTs. We suppose that low-rank structure is also beneficial to uncover the correlation between genetic variations and imaging phenotypes. Finally, we conduct regression analysis of SNPs and QTs. Experimental results show that our model is more accurate in prediction than compared methods and presents new insights of SNPs. PMID:29218896

Bergmann's rule is maintained during a rapid range expansion in a damselfly.

PubMed

Hassall, Christopher; Keat, Simon; Thompson, David J; Watts, Phillip C

2014-02-01

Climate-induced range shifts result in the movement of a sample of genotypes from source populations to new regions. The phenotypic consequences of those shifts depend upon the sample characteristics of the dispersive genotypes, which may act to either constrain or promote phenotypic divergence, and the degree to which plasticity influences the genotype-environment interaction. We sampled populations of the damselfly Erythromma viridulum from northern Europe to quantify the phenotypic (latitude-body size relationship based on seven morphological traits) and genetic (variation at microsatellite loci) patterns that occur during a range expansion itself. We find a weak spatial genetic structure that is indicative of high gene flow during a rapid range expansion. Despite the potentially homogenizing effect of high gene flow, however, there is extensive phenotypic variation among samples along the invasion route that manifests as a strong, positive correlation between latitude and body size consistent with Bergmann's rule. This positive correlation cannot be explained by variation in the length of larval development (voltinism). While the adaptive significance of latitudinal variation in body size remains obscure, geographical patterns in body size in odonates are apparently underpinned by phenotypic plasticity and this permits a response to one or more environmental correlates of latitude during a range expansion. © 2013 John Wiley & Sons Ltd.

Genetic basis of Bartter syndrome in Korea.

PubMed

Lee, Beom Hee; Cho, Hee Yeon; Lee, HyunKyung; Han, Kyoung Hee; Kang, Hee Gyung; Ha, Il Soo; Lee, Joo Hoon; Park, Young Seo; Shin, Jae Il; Lee, Dae-Yeol; Kim, Su-Yung; Choi, Yong; Cheong, Hae Il

2012-04-01

Bartter syndrome (BS) is clinically classified into antenatal or neonatal BS (aBS) and classic BS (cBS) as well as five subtypes based on the underlying mutant gene; SLC12A1 (BS I), KCNJ1 (BS II), CLCNKB (BS III), BSND (BS IV) and CASR (BS V). Clinico-genetic features of a nationwide cohort of 26 Korean children with BS were investigated. The clinical diagnosis was aBS in 8 (30.8%), cBS in 15 (57.7%) and mixed Bartter-Gitelman phenotype in 3 cases (11.5%). Five of eight patients with aBS and all 18 patients with either cBS or mixed Bartter-Gitelman phenotype had CLCNKB mutations. Among the 23 patients (46 alleles) with CLCNKB mutations, p.W610X and large deletions were detected in 25 (54.3%) and 10 (21.7%) alleles, respectively. There was no genotype-phenotype correlation in patients with CLCNKB mutations. Twenty-three (88.5%) of the 26 BS patients involved in this study had CLCNKB mutations. The p.W610X mutation and large deletion were two common types of mutations in CLCNKB. The clinical manifestations of BS III were heterogeneous without a genotype-phenotype correlation, typically manifesting cBS phenotype but also aBS or mixed Bartter-Gitelman phenotypes. The molecular diagnostic steps for patients with BS in our population should be designed taking these peculiar genotype distributions into consideration, and a new more clinically relevant classification including BS and Gitelman syndrome is required.

Coffin-Siris syndrome and the BAF complex: genotype-phenotype study in 63 patients.

PubMed

Santen, Gijs W E; Aten, Emmelien; Vulto-van Silfhout, Anneke T; Pottinger, Caroline; van Bon, Bregje W M; van Minderhout, Ivonne J H M; Snowdowne, Ronelle; van der Lans, Christian A C; Boogaard, Merel; Linssen, Margot M L; Vijfhuizen, Linda; van der Wielen, Michiel J R; Vollebregt, M J Ellen; Breuning, Martijn H; Kriek, Marjolein; van Haeringen, Arie; den Dunnen, Johan T; Hoischen, Alexander; Clayton-Smith, Jill; de Vries, Bert B A; Hennekam, Raoul C M; van Belzen, Martine J

2013-11-01

De novo germline variants in several components of the SWI/SNF-like BAF complex can cause Coffin-Siris syndrome (CSS), Nicolaides-Baraitser syndrome (NCBRS), and nonsyndromic intellectual disability. We screened 63 patients with a clinical diagnosis of CSS for these genes (ARID1A, ARID1B, SMARCA2, SMARCA4, SMARCB1, and SMARCE1) and identified pathogenic variants in 45 (71%) patients. We found a high proportion of variants in ARID1B (68%). All four pathogenic variants in ARID1A appeared to be mosaic. By using all variants from the Exome Variant Server as test data, we were able to classify variants in ARID1A, ARID1B, and SMARCB1 reliably as being pathogenic or nonpathogenic. For SMARCA2, SMARCA4, and SMARCE1 several variants in the EVS remained unclassified, underlining the importance of parental testing. We have entered all variant and clinical information in LOVD-powered databases to facilitate further genotype-phenotype correlations, as these will become increasingly important because of the uptake of targeted and untargeted next generation sequencing in diagnostics. The emerging phenotype-genotype correlation is that SMARCB1 patients have the most marked physical phenotype and severe cognitive and growth delay. The variability in phenotype seems most marked in ARID1A and ARID1B patients. Distal limbs anomalies are most marked in ARID1A patients and least in SMARCB1 patients. Numbers are small however, and larger series are needed to confirm this correlation. © 2013 WILEY PERIODICALS, INC.

Characterization of Lactobacillus from Algerian Goat’S Milk Based on Phenotypic, 16S rDNA Sequencing and their Technological Properties

PubMed Central

Marroki, Ahmed; Zúñiga, Manuel; Kihal, Mabrouk; Pérez- Martínez, Gaspar

2011-01-01

Nineteen strains of Lactobacillus isolated from goat’s milk from farms in north-west of Algeria were characterized. Isolates were identified by phenotypic, physiological and genotypic methods and some of their important technological properties were studied. Phenotypic characterization was carried out by studying physiological, morphological characteristics and carbohydrate fermentation patterns using API 50 CHL system. Isolates were also characterized by partial 16S rDNA sequencing. Results obtained with phenotypic methods were correlated with the genotypic characterization and 13 isolates were identified as L. plantarum, two isolates as L. rhamnosus and one isolate as L. fermentum. Three isolates identified as L. plantarum by phenotypic characterization were found to be L. pentosus by the genotypic method. A large diversity in technological properties (acid production in skim milk, exopolysaccharide production, aminopeptidase activity, antibacterial activity and antibiotic susceptibility) was observed. Based on these results, two strains of L. plantarum (LbMS16 and LbMS21) and one strain of L. rhamnosus (LbMF25) have been tentatively selected for use as starter cultures in the manufacture of artisanal fermented dairy products in Algeria. PMID:24031617

Correlation and path analysis of biomass sorghum production.

PubMed

Vendruscolo, T P S; Barelli, M A A; Castrillon, M A S; da Silva, R S; de Oliveira, F T; Corrêa, C L; Zago, B W; Tardin, F D

2016-12-23

Sorghum biomass is an interesting raw material for bioenergy production due to its versatility, potential of being a renewable energy source, and low-cost of production. The objective of this study was to evaluate the genetic variability of biomass sorghum genotypes and to estimate genotypic, phenotypic, and environmental correlations, and direct and indirect effects of seven agronomic traits through path analysis. Thirty-four biomass sorghum genotypes and two forage sorghum genotypes were cultivated in a randomized block design with three replicates. The following morpho-agronomic traits were evaluated: flowering date, stem diameter, number of stems, plant height, number of leaves, green mass production, and dry matter production. There were significant differences at the 1% level for all traits. The highest genotypic correlation was found between the traits green mass production and dry matter production. The path analysis demonstrated that green mass production and number of leaves can assist in the selection of dry matter production.

Third trimester fetal heart rate predicts phenotype and mutation burden in the type 1 long QT syndrome.

PubMed

Winbo, Annika; Fosdal, Inger; Lindh, Maria; Diamant, Ulla-Britt; Persson, Johan; Wettrell, Göran; Rydberg, Annika

2015-08-01

Early diagnosis and risk stratification is of clinical importance in the long QT syndrome (LQTS), however, little genotype-specific data are available regarding fetal LQTS. We investigate third trimester fetal heart rate, routinely recorded within public maternal health care, as a possible marker for LQT1 genotype and phenotype. This retrospective study includes 184 fetuses from 2 LQT1 founder populations segregating p.Y111C and p.R518X (74 noncarriers and 110 KCNQ1 mutation carriers, whereof 13 double mutation carriers). Pedigree-based measured genotype analysis revealed significant associations between fetal heart rate, genotype, and phenotype; mean third trimester prelabor fetal heart rates obtained from obstetric records (gestational week 29-41) were lower per added mutation (no mutation, 143±5 beats per minute; single mutation, 134±8 beats per minute; double mutations, 111±6 beats per minute; P<0.0001), and lower in symptomatic versus asymptomatic mutation carriers (122±10 versus 137±9 beats per minute; P<0.0001). Strong correlations between fetal heart rate and neonatal heart rate (r=0.700; P<0.001), and postnatal QTc (r=-0.762; P<0.001) were found. In a multivariable model, fetal genotype explained the majority of variance in fetal heart rate (-10 beats per minute per added mutation; P<1.0×10(-23)). Arrhythmia symptoms and intrauterine β-blocker exposure each predicted -7 beats per minute, P<0.0001. In this study including 184 fetuses from 2 LQT1 founder populations, third trimester fetal heart rate discriminated between fetal genotypes and correlated with severity of postnatal cardiac phenotype. This finding strengthens the role of fetal heart rate in the early detection and risk stratification of LQTS, particularly for fetuses with double mutations, at high risk of early life-threatening arrhythmias. © 2015 American Heart Association, Inc.

Ambient temperature and genotype differentially affect developmental and phenotypic plasticity in Arabidopsis thaliana.

PubMed

Ibañez, Carla; Poeschl, Yvonne; Peterson, Tom; Bellstädt, Julia; Denk, Kathrin; Gogol-Döring, Andreas; Quint, Marcel; Delker, Carolin

2017-07-06

Global increase in ambient temperatures constitute a significant challenge to wild and cultivated plant species. Forward genetic analyses of individual temperature-responsive traits have resulted in the identification of several signaling and response components. However, a comprehensive knowledge about temperature sensitivity of different developmental stages and the contribution of natural variation is still scarce and fragmented at best. Here, we systematically analyze thermomorphogenesis throughout a complete life cycle in ten natural Arabidopsis thaliana accessions grown under long day conditions in four different temperatures ranging from 16 to 28 °C. We used Q 10 , GxE, phenotypic divergence and correlation analyses to assess temperature sensitivity and genotype effects of more than 30 morphometric and developmental traits representing five phenotype classes. We found that genotype and temperature differentially affected plant growth and development with variing strengths. Furthermore, overall correlations among phenotypic temperature responses was relatively low which seems to be caused by differential capacities for temperature adaptations of individual accessions. Genotype-specific temperature responses may be attractive targets for future forward genetic approaches and accession-specific thermomorphogenesis maps may aid the assessment of functional relevance of known and novel regulatory components.

Genotypic richness predicts phenotypic variation in an endangered clonal plant

PubMed Central

Sinclair, Elizabeth A.; Poore, Alistair G.B.; Bain, Keryn F.; Vergés, Adriana

2016-01-01

Declines in genetic diversity within a species can affect the stability and functioning of populations. The conservation of genetic diversity is thus a priority, especially for threatened or endangered species. The importance of genetic variation, however, is dependent on the degree to which it translates into phenotypic variation for traits that affect individual performance and ecological processes. This is especially important for predominantly clonal species, as no single clone is likely to maximise all aspects of performance. Here we show that intraspecific genotypic diversity as measured using microsatellites is a strong predictor of phenotypic variation in morphological traits and shoot productivity of the threatened, predominantly clonal seagrass Posidonia australis, on the east coast of Australia. Biomass and surface area variation was most strongly predicted by genotypic richness, while variation in leaf chemistry (phenolics and nitrogen) was unrelated to genotypic richness. Genotypic richness did not predict tissue loss to herbivores or epiphyte load, however we did find that increased herbivore damage was positively correlated with allelic richness. Although there was no clear relationship between higher primary productivity and genotypic richness, variation in shoot productivity within a meadow was significantly greater in more genotypically diverse meadows. The proportion of phenotypic variation explained by environmental conditions varied among different genotypes, and there was generally no variation in phenotypic traits among genotypes present in the same meadows. Our results show that genotypic richness as measured through the use of presumably neutral DNA markers does covary with phenotypic variation in functionally relevant traits such as leaf morphology and shoot productivity. The remarkably long lifespan of individual Posidonia plants suggests that plasticity within genotypes has played an important role in the longevity of the species. However, the strong link between genotypic and phenotypic variation suggests that a range of genotypes is still the best case scenario for adaptation to and recovery from predicted environmental change. PMID:26925313

Neural correlates of abnormal sensory discrimination in laryngeal dystonia.

PubMed

Termsarasab, Pichet; Ramdhani, Ritesh A; Battistella, Giovanni; Rubien-Thomas, Estee; Choy, Melissa; Farwell, Ian M; Velickovic, Miodrag; Blitzer, Andrew; Frucht, Steven J; Reilly, Richard B; Hutchinson, Michael; Ozelius, Laurie J; Simonyan, Kristina

2016-01-01

Aberrant sensory processing plays a fundamental role in the pathophysiology of dystonia; however, its underpinning neural mechanisms in relation to dystonia phenotype and genotype remain unclear. We examined temporal and spatial discrimination thresholds in patients with isolated laryngeal form of dystonia (LD), who exhibited different clinical phenotypes (adductor vs. abductor forms) and potentially different genotypes (sporadic vs. familial forms). We correlated our behavioral findings with the brain gray matter volume and functional activity during resting and symptomatic speech production. We found that temporal but not spatial discrimination was significantly altered across all forms of LD, with higher frequency of abnormalities seen in familial than sporadic patients. Common neural correlates of abnormal temporal discrimination across all forms were found with structural and functional changes in the middle frontal and primary somatosensory cortices. In addition, patients with familial LD had greater cerebellar involvement in processing of altered temporal discrimination, whereas sporadic LD patients had greater recruitment of the putamen and sensorimotor cortex. Based on the clinical phenotype, adductor form-specific correlations between abnormal discrimination and brain changes were found in the frontal cortex, whereas abductor form-specific correlations were observed in the cerebellum and putamen. Our behavioral and neuroimaging findings outline the relationship of abnormal sensory discrimination with the phenotype and genotype of isolated LD, suggesting the presence of potentially divergent pathophysiological pathways underlying different manifestations of this disorder.

Evaluation of Lactococcus lactis Isolates from Nondairy Sources with Potential Dairy Applications Reveals Extensive Phenotype-Genotype Disparity and Implications for a Revised Species

PubMed Central

Cavanagh, Daniel; Casey, Aidan; Altermann, Eric; Cotter, Paul D.; Fitzgerald, Gerald F.

2015-01-01

Lactococcus lactis is predominantly associated with dairy fermentations, but evidence suggests that the domesticated organism originated from a plant niche. L. lactis possesses an unusual taxonomic structure whereby strain phenotypes and genotypes often do not correlate, which in turn has led to confusion in L. lactis classification. A bank of L. lactis strains was isolated from various nondairy niches (grass, vegetables, and bovine rumen) and was further characterized on the basis of key technological traits, including growth in milk and key enzyme activities. Phenotypic analysis revealed all strains from nondairy sources to possess an L. lactis subsp. lactis phenotype (lactis phenotype); however, seven of these strains possessed an L. lactis subsp. cremoris genotype (cremoris genotype), determined by two separate PCR assays. Multilocus sequence typing (MLST) showed that strains with lactis and cremoris genotypes clustered together regardless of habitat, but it highlighted the increased diversity that exists among “wild” strains. Calculation of average nucleotide identity (ANI) and tetranucleotide frequency correlation coefficients (TETRA), using the JSpecies software tool, revealed that L. lactis subsp. cremoris and L. lactis subsp. lactis differ in ANI values by ∼14%, below the threshold set for species circumscription. Further analysis of strain TIFN3 and strains from nonindustrial backgrounds revealed TETRA values of <0.99 in addition to ANI values of <95%, implicating that these two groups are separate species. These findings suggest the requirement for a revision of L. lactis taxonomy. PMID:25841018

Glutathione S-transferase gene polymorphisms in celiac disease and their correlation with genomic instability phenotype.

PubMed

Fundia, Ariela F; Weich, Natalia; Crivelli, Adriana; La Motta, Graciela; Larripa, Irene B; Slavutsky, Irma

2014-06-01

Genomic instability and reduced glutathione S-transferase (GST) activity have been identified as potential risk factors for malignant complications in celiac disease (CD). In this study, we assessed the possible influence of GST polymorphisms on genome instability phenotypes in a genetically characterised group of celiac patients from previous studies. The deletion polymorphisms in GSTM1 and GSTT1 genes and the single-nucleotide polymorphism GSTP1 c.313A>G were genotyped using PCR in a set of 20 untreated adult patients with a known genomic instability phenotype and 69 age- and sex-matched healthy individuals. The frequencies of variant genotypes in patients were GSTM1-null (30%), GSTT1-null (5%), GSTP1-AG (60%) and GSTP1-GG (15%), and they showed no differences from controls. No significant differences were found in the genotype distribution based on telomere length. Cases with GSTM1-null genotype (83%) and microsatellite stability were more frequent than those with genomic instability. Moreover, carriers of GSTP1-variant genotype (73%) and stable phenotype were significantly increased compared to unstable patients (27%) (P=0.031). No differences were found according to the clinical-pathological characteristics of celiac cases. No association between GST polymorphic variants and celiac-associated genomic instability was proven in our cohort. Future studies should explore the usefulness of other biomarkers to distinguish celiac patients who are susceptible to cancer development. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Identification of mutations, genotype-phenotype correlation and prenatal diagnosis of maple syrup urine disease in Indian patients.

PubMed

Gupta, Deepti; Bijarnia-Mahay, Sunita; Saxena, Renu; Kohli, Sudha; Dua-Puri, Ratna; Verma, Jyotsna; Thomas, E; Shigematsu, Yosuke; Yamaguchi, Seiji; Deb, Roumi; Verma, Ishwar Chander

2015-09-01

Maple syrup urine disease (MSUD) is caused by mutations in genes BCKDHA, BCKDHB, DBT encoding E1α, E1β, and E2 subunits of enzyme complex, branched-chain alpha-ketoacid dehydrogenase (BCKDH). BCKDH participates in catabolism of branched-chain amino acids (BCAAs) - leucine, isoleucine and valine in the energy production pathway. Deficiency or defect in the enzyme complex causes accumulation of BCAAs and keto-acids leading to toxicity. Twenty-four patients with MSUD were enrolled in the study for molecular characterization and genotype-phenotype correlation. Molecular studies were carried out by sequencing of the 3 genes by Sanger method. Bioinformatics tools were employed to classify novel variations into pathogenic or benign. The predicted effects of novel changes on protein structure were elucidated by 3D modeling. Mutations were detected in 22 of 24 patients (11, 7 and 4 in BCKDHB, BCKDHA and DBT genes, respectively). Twenty mutations including 11 novel mutations were identified. Protein modeling in novel mutations showed alteration of structure and function of these subunits. Mutations, c.1065 delT (BCKDHB gene) and c.939G > C (DBT gene) were noted to be recurrent, identified in 6 of 22 alleles and 5 of 8 alleles, respectively. Two-third patients were of neonatal classical phenotype (16 of 24). BCKDHB gene mutations were present in 10 of these 16 patients. Prenatal diagnoses were performed in 4 families. Consanguinity was noted in 37.5% families. Although no obvious genotype-phenotype correlation could be found in our study, most cases with mutation in BCKDHB gene presented in neonatal period. Large number of novel mutations underlines the heterogeneity and distinctness of gene pool from India. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Genotype-Phenotype Correlations in Multiple Sclerosis: "HLA" Genes Influence Disease Severity Inferred by [superscript 1]HMR Spectroscopy and MRI Measures

ERIC Educational Resources Information Center

Okuda, D. T.; Srinivasan, R.; Oksenberg, J. R.; Goodin, D. S.; Baranzini, S. E.; Beheshtian, A.; Waubant, E.; Zamvil, S. S.; Leppert, D.; Qualley, P.; Lincoln, R.; Gomez, R.; Caillier, S.; George, M.; Wang, J.; Nelson, S. J.; Cree, B. A. C.; Hauser, S. L.; Pelletier, D.

2009-01-01

Genetic susceptibility to multiple sclerosis (MS) is associated with the human leukocyte antigen (HLA) "DRB1*1501" allele. Here we show a clear association between DRB1*1501 carrier status and four domains of disease severity in an investigation of genotype-phenotype associations in 505 robust, clinically well characterized MS patients evaluated…

Joint analysis of phenotypic and molecular diversity provides new insights on the genetic variability of the Brazilian physic nut germplasm bank

PubMed Central

Alves, Alexandre Alonso; Bhering, Leonardo Lopes; Rosado, Tatiana Barbosa; Laviola, Bruno Galvêas; Formighieri, Eduardo Fernandes; Cruz, Cosme Damião

2013-01-01

The genetic variability of the Brazilian physic nut (Jatropha curcas) germplasm bank (117 accessions) was assessed using a combination of phenotypic and molecular data. The joint dissimilarity matrix showed moderate correlation with the original matrices of phenotypic and molecular data. However, the correlation between the phenotypic dissimilarity matrix and the genotypic dissimilarity matrix was low. This finding indicated that molecular markers (RAPD and SSR) did not adequately sample the genomic regions that were relevant for phenotypic differentiation of the accessions. The dissimilarity values of the joint dissimilarity matrix were used to measure phenotypic + molecular diversity. This diversity varied from 0 to 1.29 among the 117 accessions, with an average dissimilarity among genotypes of 0.51. Joint analysis of phenotypic and molecular diversity indicated that the genetic diversity of the physic nut germplasm was 156% and 64% higher than the diversity estimated from phenotypic and molecular data, respectively. These results show that Jatropha genetic variability in Brazil is not as limited as previously thought. PMID:24130445

Joint analysis of phenotypic and molecular diversity provides new insights on the genetic variability of the Brazilian physic nut germplasm bank.

PubMed

Alves, Alexandre Alonso; Bhering, Leonardo Lopes; Rosado, Tatiana Barbosa; Laviola, Bruno Galvêas; Formighieri, Eduardo Fernandes; Cruz, Cosme Damião

2013-09-01

The genetic variability of the Brazilian physic nut (Jatropha curcas) germplasm bank (117 accessions) was assessed using a combination of phenotypic and molecular data. The joint dissimilarity matrix showed moderate correlation with the original matrices of phenotypic and molecular data. However, the correlation between the phenotypic dissimilarity matrix and the genotypic dissimilarity matrix was low. This finding indicated that molecular markers (RAPD and SSR) did not adequately sample the genomic regions that were relevant for phenotypic differentiation of the accessions. The dissimilarity values of the joint dissimilarity matrix were used to measure phenotypic + molecular diversity. This diversity varied from 0 to 1.29 among the 117 accessions, with an average dissimilarity among genotypes of 0.51. Joint analysis of phenotypic and molecular diversity indicated that the genetic diversity of the physic nut germplasm was 156% and 64% higher than the diversity estimated from phenotypic and molecular data, respectively. These results show that Jatropha genetic variability in Brazil is not as limited as previously thought.

Effect of the F508del genotype on outcomes of endoscopic sinus surgery in children with cystic fibrosis.

PubMed

Do, Bao Anh Julie; Lands, Larry C; Saint-Martin, Christine; Mascarella, Marco A; Manoukian, John J; Daniel, Sam J; Nguyen, Lily H P

2014-07-01

Numerous authors have sought to describe genotype-phenotype correlations in cystic fibrosis (CF), notably to pancreatic insufficiency and lung disease. However, few studies have focused on the association between the F508del genotype and response to sinus surgery. The objective of this study is to assess the effect of the F508del genotype on sinonasal disease severity and outcomes following functional endoscopic sinus surgery (FESS) in a pediatric population. A retrospective chart review of 153 children with CF seen at a tertiary care pediatric hospital from 1995 to 2008 was performed. Patients were classified into one of three groups according to F508del genotype, either as homozygous, heterozygous or not carrying a F508del mutation. The sinonasal disease phenotype of the three groups was compared based on clinical and radiological findings, extent of endoscopic sinus surgery and rate of revision surgery. The relationship between the F508del genotype and pancreatic insufficiency was confirmed (p<0.05). There was no association between the F508del genotype and increased need for FESS (p=0.75). Moreover, no association was established between F508del homozygosity and presence of nasal polyps, Lund-Mackay score, extent of surgery or length of postoperative hospitalization. The rates of revision surgery did not differ significantly among the three genotypes analyzed (p=0.59). There is no clear association between the F508del genotype and an increased need for FESS, extent of surgery, or revision surgery. Given the phenotypic variability of sinonasal disease in patients with CF, a prospective study is needed to better understand outcomes following FESS and the contribution of gene modifiers to this effect. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Correlations and path analysis among agronomic and technological traits of upland cotton.

PubMed

Farias, F J C; Carvalho, L P; Silva Filho, J L; Teodoro, P E

2016-08-12

To date, path analysis has been used with the aim of breeding different cultures. However, for cotton, there have been few studies using this analysis, and all of these have used fiber productivity as the primary dependent variable. Therefore, the aim of the present study was to identify agronomic and technological properties that can be used as criteria for direct and indirect phenotypes in selecting cotton genotypes with better fibers. We evaluated 16 upland cotton genotypes in eight trials conducted during the harvest 2008/2009 in the State of Mato Grosso, using a randomized block design with four replicates. The evaluated traits were: plant height, average boll weight, percentage of fiber, cotton seed yield, fiber length, uniformity of fiber, short fiber index, fiber strength, elongation, maturity of the fibers, micronaire, reflectance, and the degree of yellowing. Phenotypic correlations between the traits and cotton fiber yield (main dependent variable) were unfolded in direct and indirect effects through path analysis. Fiber strength, uniformity of fiber, and reflectance were found to influence fiber length, and therefore, these traits are recommended for both direct and indirect selection of cotton genotypes.

Genotype-phenotype correlation in FMF patients: A "non classic" recessive autosomal or "atypical" dominant autosomal inheritance?

PubMed

Procopio, V; Manti, S; Bianco, G; Conti, G; Romeo, A; Maimone, F; Arrigo, T; Cutrupi, M C; Salpietro, C; Cuppari, C

2018-01-30

Uncertainty remains on the pathogenetic mechanisms, model of inheritance as well as genotype-phenotype correlation of FMF disease. To investigate the impact of genetic factors on the FMF phenotype and the disease inheritance model. A total of 107 FMF patients were enrolled. Patients were diagnosed clinically. All patients underwent genetic analysis of the FMF locus on 16p13.3. 9 distinct mutations were detected. Specifically, the 85.98% of patients showed a heterozygous genotype. The most common genotypes were p.Met680Ile/wt and p.Met694Val/wt. The most frequent clinical findings were fever, abdominal pain, joint pain, thoracic pain, and erysipelas-like erythema. Analysis of clinical data did not detect any significant difference in clinical phenotype among heterozygous, homozygous as well as compound homozygous subjects, further supporting the evidence that, contrary to the recessive autosomal inheritance, heterozygous patients fulfilled the criteria of clinical FMF. Moreover, subjects with p.Met694Val/wt and p.Met680Ile/wt genotype reported the most severe clinical phenotype. p.Ala744Ser/wt, p.Glu148Gln/Met680Ile, p.Met680Ile/Met680Ile, p.Met680Ile/Met694Val, p.Pro369Ser/wt, p.Met694Ile/wt, p.Glu148Gln/Glu148Gln, p.Lys695Arg/wt resulted in 100% pathogenicity. The existence of a "non classic" autosomal recessive inheritance as well as of an "atypical" dominant autosomal inheritance with incomplete penetrance and variable expressivity cannot be excluded in FMF. Copyright © 2017 Elsevier B.V. All rights reserved.

PAH mutation spectrum and correlation with PKU manifestation in north Jiangsu province population.

PubMed

Wang, Zhen-Wen; Jiang, Shi-Wen; Zhou, Bao-Cheng

2018-02-01

Phenylketonuria (PKU) is a common autosomal recessive disorder of phenylalanine metabolism and mainly results a deficiency of phenylalanine hydroxylase gene (PAH). The incidence of various PAH mutations have race and ethnicity differences. We report a spectrum of PAH mutations complied from 35 PKU children who are all Chinese Han population from north Jiangsu in this study. All 13 exons and their flanking intron sequences of PAH were determined by Ion Torrent PGM™ sequencing. The relationship of genotype and phenotype was analyzed based on the sum of the arbitrary value (AV) values of the two alleles. We identified 61 mutations, with a frequency of 87.14%, among 70 alleles of 35 patients. The most prevalent mutations were R243Q (26.23%), R241C (9.84%) and V399V (8.20%). Furthermore, the consistency between prediction of the biochemical phenotype and the observed phenotype was 81.25%, with the highest consistency observed in classic PKU (87.50%). A significant correlation was found between pretreatment levels of phenylalanine and AV sum (r = -0.87, P < 0.05). Finally, our study constructs PAH mutation spectrum by next generation sequencing (NGS), and reveals that the PAH genotypes and biochemical phenotypes were significantly correlated. These offers facilitate the provision of appropriate genetic counseling for PKU patients. Copyright © 2017. Published by Elsevier Taiwan.

Nonlinear Dynamics in Gene Regulation Promote Robustness and Evolvability of Gene Expression Levels.

PubMed

Steinacher, Arno; Bates, Declan G; Akman, Ozgur E; Soyer, Orkun S

2016-01-01

Cellular phenotypes underpinned by regulatory networks need to respond to evolutionary pressures to allow adaptation, but at the same time be robust to perturbations. This creates a conflict in which mutations affecting regulatory networks must both generate variance but also be tolerated at the phenotype level. Here, we perform mathematical analyses and simulations of regulatory networks to better understand the potential trade-off between robustness and evolvability. Examining the phenotypic effects of mutations, we find an inverse correlation between robustness and evolvability that breaks only with nonlinearity in the network dynamics, through the creation of regions presenting sudden changes in phenotype with small changes in genotype. For genotypes embedding low levels of nonlinearity, robustness and evolvability correlate negatively and almost perfectly. By contrast, genotypes embedding nonlinear dynamics allow expression levels to be robust to small perturbations, while generating high diversity (evolvability) under larger perturbations. Thus, nonlinearity breaks the robustness-evolvability trade-off in gene expression levels by allowing disparate responses to different mutations. Using analytical derivations of robustness and system sensitivity, we show that these findings extend to a large class of gene regulatory network architectures and also hold for experimentally observed parameter regimes. Further, the effect of nonlinearity on the robustness-evolvability trade-off is ensured as long as key parameters of the system display specific relations irrespective of their absolute values. We find that within this parameter regime genotypes display low and noisy expression levels. Examining the phenotypic effects of mutations, we find an inverse correlation between robustness and evolvability that breaks only with nonlinearity in the network dynamics. Our results provide a possible solution to the robustness-evolvability trade-off, suggest an explanation for the ubiquity of nonlinear dynamics in gene expression networks, and generate useful guidelines for the design of synthetic gene circuits.

Association of CDH13 Genotypes/Haplotypes with Circulating Adiponectin Levels, Metabolic Syndrome, and Related Metabolic Phenotypes: The Role of the Suppression Effect

PubMed Central

Teng, Ming-Sheng; Hsu, Lung-An; Wu, Semon; Sun, Yu-Chen; Juan, Shu-Hui; Ko, Yu-Lin

2015-01-01

Objective Previous genome-wide association studies have indicated an association between CDH13 genotypes and adiponectin levels. In this study, we used mediation analysis to assess the statistical association between CDH13 locus variants and adiponectin levels, metabolic syndrome, and related metabolic phenotypes. Methods and results A sample population of 530 Taiwanese participants was enrolled. Four CDH13 gene variants in the promoter and intron 1 regions were genotyped. After adjustment for clinical covariates, the CDH13 genotypes/haplotypes exhibited an association with the adiponectin levels (lowest P = 1.95 × 10−11 for rs4783244 and lowest P = 3.78 × 10−13 for haplotype ATTT). Significant correlations were observed between the adiponectin levels and the various metabolic syndrome-related phenotypes (all P ≤ 0.005). After further adjustment for the adiponectin levels, participants with a minor allele of rs12051272 revealed a considerable association with a more favorable metabolic profile, including higher insulin sensitivity, high-density lipoprotein cholesterol levels, lower diastolic blood pressure, circulating levels of fasting plasma glucose, and triglycerides, and as a lower risk of metabolic syndrome (all P < 0.05). The mediation analysis further revealed a suppression effect of the adiponectin levels on the association between CDH13 genotypes and metabolic syndrome and its related phenotypes (Sobel test; all P < 0.001). Conclusion The genetic polymorphisms at the CDH13 locus independently affect the adiponectin levels, whereas the adiponectin levels exhibit a suppressive effect on the association between CDH13 locus variants and various metabolic phenotypes and metabolic syndrome. In addition, these results provide further evidence of the association between the CDH13 gene variants and the risks of metabolic syndrome and atherosclerotic cardiovascular disease. PMID:25875811

PDK2 and ABCG2 genes polymorphisms are correlated with blood glucose levels and uric acid in Tibetan gout patients.

PubMed

Ren, Y C; Jin, T B; Sun, X D; Geng, T T; Zhang, M X; Wang, L; Feng, T; Kang, L L; Chen, C

2016-02-11

Previous studies have shown that the PDK2 and ABCG2 genes play important roles in many aspects of gout development in European populations. However, a detailed genotype-phenotype analysis was not performed. The aim of the present study was to investigate the potential association between variants in these two genes and metabolism-related quantitative phenotypes relevant to gout in a Chinese Tibetan population. In total, 316 Chinese Tibetan gout patients were recruited from rheumatology outpatient clinics and 6 single nucleotide polymorphisms in PDK2 and ABCG2 were genotyped, which were possible etiologic variants as identified in the HapMap Chinese Han Beijing population. A significant difference in blood glucose levels was detected between different genotypes of rs2728109 (P = 0.005) in the PDK2 gene. We also detected a significant difference in the mean serum uric levels between different genotypes of rs3114018 (P = 0.004) in the ABCG2 gene. All P values remained significant after Bonferroni's correction for multiple testing. Our data demonstrate potential roles for PDK2 and ABCG2 polymorphisms in the metabolic phenotypes of Tibetan gout patients, which may provide new insights into the etiology of gout. Further studies are required to confirm these findings.

Minimum number of measurements for evaluating soursop (Annona muricata L.) yield.

PubMed

Sánchez, C F B; Teodoro, P E; Londoño, S; Silva, L A; Peixoto, L A; Bhering, L L

2017-05-31

Repeatability studies on fruit species are of great importance to identify the minimum number of measurements necessary to accurately select superior genotypes. This study aimed to identify the most efficient method to estimate the repeatability coefficient (r) and predict the minimum number of measurements needed for a more accurate evaluation of soursop (Annona muricata L.) genotypes based on fruit yield. Sixteen measurements of fruit yield from 71 soursop genotypes were carried out between 2000 and 2016. In order to estimate r with the best accuracy, four procedures were used: analysis of variance, principal component analysis based on the correlation matrix, principal component analysis based on the phenotypic variance and covariance matrix, and structural analysis based on the correlation matrix. The minimum number of measurements needed to predict the actual value of individuals was estimated. Principal component analysis using the phenotypic variance and covariance matrix provided the most accurate estimates of both r and the number of measurements required for accurate evaluation of fruit yield in soursop. Our results indicate that selection of soursop genotypes with high fruit yield can be performed based on the third and fourth measurements in the early years and/or based on the eighth and ninth measurements at more advanced stages.

The role of mutation analysis of the APC gene in the management of FAP patients. A controversial issue.

PubMed

Dodaro, Concetta; Grifasi, Carlo; Florio, Jole; Santangelo, Michele L; Duraturo, Francesca; De Rosa, Marina; Izzo, Paola; Renda, Andrea

A correlation between the location of mutation in the adenomatous polyposis coli (APC) gene and clinical manifestations of familial adenomatous polyposis (FAP) has repeatedly been reported. Some Authors suggest the use of mutational analysis as a guide to select the best surgical option in FAP patients. However, data coming from studies on large series have raised questions on this issue. The aim of this study is to discuss the role of the genetic tests in the management of FAP. A literature review was performed considering only peer-reviewed articles published between 1991-2015. All the studies examined the role of genetic as a guide for surgical management of FAP. Of 363 articles identified, 21 were selected for full-text review. We found different positions with regard the use of genetic tests to determine surgical management of FAP. In particular, while consistent correlations between the APC mutation site and FAP phenotype were observed in large series, 8 studies reported a wide variation of genotypephenotype correlation in patients with the same mutation and they recommended that decisions regarding surgical strategy should be based not only on genotype but also on the clinical factors and the will of the patient who must be fully informed. The decision on the type and the timing of surgery should be based on the assessment of many factors and genotype assessment should be used in combination with clinical data. Disease severity, Familial adenomatous polyposis, Genetic tests, Genotype-phenotype correlations, Surgical management.

FY*A silencing by the GATA-motif variant FY*A(-69C) in a Caucasian family.

PubMed

Písačka, Martin; Marinov, Iuri; Králová, Miroslava; Králová, Jana; Kořánová, Michaela; Bohoněk, Miloš; Sood, Chhavi; Ochoa-Garay, Gorka

2015-11-01

The c.1-67C variant polymorphism in a GATA motif of the FY promoter is known to result in erythroid-specific FY silencing, that is, in Fy(a-) and Fy(b-) phenotypes. A Caucasian donor presented with the very rare Fy(a-b-) phenotype and was further investigated. Genomic DNA was analyzed by sequencing to identify the cause of the Fy(a-b-) phenotype. Samples were collected from some of his relatives to establish a correlation between the serology and genotyping results. Red blood cells were analyzed by gel column agglutination and flow cytometry. Genomic DNA was analyzed on genotyping microarrays, by DNA sequencing and by allele-specific PCR. In the donor, a single-nucleotide polymorphism T>C within the GATA motif was found at Position c.1-69 of the FY promoter and shown to occur in the FY*A allele. His genotype was found to be FY*A(-69C), FY*BW.01. In six FY*A/FY*B heterozygous members of the family, a perfect correlation was found between the presence vs. absence of the FY*A(-69C) variant allele and a Fy(a-) vs. Fy(a+) phenotype. The location of the c.1-69C polymorphism in a GATA motif whose disruption is known to result in a Fy null phenotype, together with the perfect correlation between the presence of the FY*A(-69C) allele and the Fy(a-) phenotype support a cause-effect relationship between the two. © 2015 AABB.

Functional Significance of Single Nucleotide Polymorphisms in the Lactase Gene in Diverse United States Subjects and Evidence for a Novel Lactase Persistence Allele at -13909 in Those of European Ancestry

PubMed Central

Baffour-Awuah, Nana Yaa; Fleet, Sarah; Baker, Susan S.; Butler, Johannah L.; Campbell, Catarina; Tischfield, Samuel; Mitchell, Paul D.; Moon, Jennifer E.; Allende-Richter, Sophie; Fishman, Laurie; Bousvaros, Athos; Fox, Victor; Kuokkanen, Mikko; Montgomery, Robert K.; Grand, Richard J.; Hirschhorn, Joel N.

2014-01-01

Objectives Recent data from mainly homogeneous European and African populations implicate a 140 bp region 5′ to the transcriptional start site of LCT (the lactase gene) as a regulatory site for lactase persistence and non-persistence. As there are no studies of United States non-homogeneous populations, we performed genotype/phenotype analysis of the -13910 and -22018 LCT SNPs in New England children, mostly of European ancestry. Methods Duodenal biopsies were processed for disaccharidase activities, RNA quantification by RT-PCR, allelic expression ratios by PCR, and genotyping and SNP analysis. Results were compared to clinical information. Results Lactase activity and mRNA levels, as well as sucrase-to-lactase ratios of enzyme activity and mRNA, showed robust correlations with genotype. None of the other LCT SNPs showed as strong a correlation with enzyme or mRNA activities as did -13910. Data were consistent with the -13910 being the causal sequence variant rather than -22018. Four individuals heterozygous for -13910T/C had allelic expression patterns similar to individuals with -13910C/C genotypes; of these, 2 showed equal LCT expression from the 2 alleles and a novel variant (-13909C>A) associated with lactase persistence. Conclusion The identification of -13910C/C genotype is very likely to predict lactase non-persistence, consistent with prior published studies. A -13910T/T genotype will frequently, but not perfectly, predict lactase persistence in this mixed European-ancestry population; a -13910T/C genotype will not predict the phenotype. A long, rare haplotype in 2 individuals with -13910T/C genotype but equal allele-specific expression contains a novel lactase persistence allele present at -13909. PMID:25625576

High Incidence of Noonan Syndrome Features Including Short Stature and Pulmonic Stenosis in Patients carrying NF1 Missense Mutations Affecting p.Arg1809: Genotype-Phenotype Correlation.

PubMed

Rojnueangnit, Kitiwan; Xie, Jing; Gomes, Alicia; Sharp, Angela; Callens, Tom; Chen, Yunjia; Liu, Ying; Cochran, Meagan; Abbott, Mary-Alice; Atkin, Joan; Babovic-Vuksanovic, Dusica; Barnett, Christopher P; Crenshaw, Melissa; Bartholomew, Dennis W; Basel, Lina; Bellus, Gary; Ben-Shachar, Shay; Bialer, Martin G; Bick, David; Blumberg, Bruce; Cortes, Fanny; David, Karen L; Destree, Anne; Duat-Rodriguez, Anna; Earl, Dawn; Escobar, Luis; Eswara, Marthanda; Ezquieta, Begona; Frayling, Ian M; Frydman, Moshe; Gardner, Kathy; Gripp, Karen W; Hernández-Chico, Concepcion; Heyrman, Kurt; Ibrahim, Jennifer; Janssens, Sandra; Keena, Beth A; Llano-Rivas, Isabel; Leppig, Kathy; McDonald, Marie; Misra, Vinod K; Mulbury, Jennifer; Narayanan, Vinodh; Orenstein, Naama; Galvin-Parton, Patricia; Pedro, Helio; Pivnick, Eniko K; Powell, Cynthia M; Randolph, Linda; Raskin, Salmo; Rosell, Jordi; Rubin, Karol; Seashore, Margretta; Schaaf, Christian P; Scheuerle, Angela; Schultz, Meredith; Schorry, Elizabeth; Schnur, Rhonda; Siqveland, Elizabeth; Tkachuk, Amanda; Tonsgard, James; Upadhyaya, Meena; Verma, Ishwar C; Wallace, Stephanie; Williams, Charles; Zackai, Elaine; Zonana, Jonathan; Lazaro, Conxi; Claes, Kathleen; Korf, Bruce; Martin, Yolanda; Legius, Eric; Messiaen, Ludwine

2015-11-01

Neurofibromatosis type 1 (NF1) is one of the most frequent genetic disorders, affecting 1:3,000 worldwide. Identification of genotype-phenotype correlations is challenging because of the wide range clinical variability, the progressive nature of the disorder, and extreme diversity of the mutational spectrum. We report 136 individuals with a distinct phenotype carrying one of five different NF1 missense mutations affecting p.Arg1809. Patients presented with multiple café-au-lait macules (CALM) with or without freckling and Lisch nodules, but no externally visible plexiform neurofibromas or clear cutaneous neurofibromas were found. About 25% of the individuals had Noonan-like features. Pulmonic stenosis and short stature were significantly more prevalent compared with classic cohorts (P < 0.0001). Developmental delays and/or learning disabilities were reported in over 50% of patients. Melanocytes cultured from a CALM in a segmental NF1-patient showed two different somatic NF1 mutations, p.Arg1809Cys and a multi-exon deletion, providing genetic evidence that p.Arg1809Cys is a loss-of-function mutation in the melanocytes and causes a pigmentary phenotype. Constitutional missense mutations at p.Arg1809 affect 1.23% of unrelated NF1 probands in the UAB cohort, therefore this specific NF1 genotype-phenotype correlation will affect counseling and management of a significant number of patients. © 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc.

Glucose-6-phosphate dehydrogenase deficiency: correlation between the genotype, biochemistry and phenotype.

PubMed

Chan, Daisy K L

2008-12-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common genetic enzyme defect present in many people from African, Middle Eastern, Mediterranean and Asian countries. Individuals with the enzyme deficiency may remain asymptomatic, develop an acute haemolytic crises to infections or Fava beans, neonatal jaundice or chronic non-spherocytic haemolytic anaemia. Electrophoretic mobility may be fast, slow or normal. Over 160 mutations have been described, mostly due to single amino acid substitution. Although correlation of the genotype and biochemistry with the clinical phenotype of G6PD deficient individuals remains somewhat variable, there is better correlation among individuals presenting with chronic non-spherocytic haemolytic anaemia, which is related to the NADP structure of the enzyme.

Novel Phenotype-Genotype Correlations of Restrictive Cardiomyopathy With Myosin-Binding Protein C (MYBPC3) Gene Mutations Tested by Next-Generation Sequencing.

PubMed

Wu, Wei; Lu, Chao-Xia; Wang, Yi-Ning; Liu, Fang; Chen, Wei; Liu, Yong-Tai; Han, Ye-Chen; Cao, Jian; Zhang, Shu-Yang; Zhang, Xue

2015-07-10

MYBPC3 dysfunctions have been proven to induce dilated cardiomyopathy, hypertrophic cardiomyopathy, and/or left ventricular noncompaction; however, the genotype-phenotype correlation between MYBPC3 and restrictive cardiomyopathy (RCM) has not been established. The newly developed next-generation sequencing method is capable of broad genomic DNA sequencing with high throughput and can help explore novel correlations between genetic variants and cardiomyopathies. A proband from a multigenerational family with 3 live patients and 1 unrelated patient with clinical diagnoses of RCM underwent a next-generation sequencing workflow based on a custom AmpliSeq panel, including 64 candidate pathogenic genes for cardiomyopathies, on the Ion Personal Genome Machine high-throughput sequencing benchtop instrument. The selected panel contained a total of 64 genes that were reportedly associated with inherited cardiomyopathies. All patients fulfilled strict criteria for RCM with clinical characteristics, echocardiography, and/or cardiac magnetic resonance findings. The multigenerational family with 3 adult RCM patients carried an identical nonsense MYBPC3 mutation, and the unrelated patient carried a missense mutation in the MYBPC3 gene. All of these results were confirmed by the Sanger sequencing method. This study demonstrated that MYBPC3 gene mutations, revealed by next-generation sequencing, were associated with familial and sporadic RCM patients. It is suggested that the next-generation sequencing platform with a selected panel provides a highly efficient approach for molecular diagnosis of hereditary and idiopathic RCM and helps build new genotype-phenotype correlations. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

The genotype-phenotype map of an evolving digital organism.

PubMed

Fortuna, Miguel A; Zaman, Luis; Ofria, Charles; Wagner, Andreas

2017-02-01

To understand how evolving systems bring forth novel and useful phenotypes, it is essential to understand the relationship between genotypic and phenotypic change. Artificial evolving systems can help us understand whether the genotype-phenotype maps of natural evolving systems are highly unusual, and it may help create evolvable artificial systems. Here we characterize the genotype-phenotype map of digital organisms in Avida, a platform for digital evolution. We consider digital organisms from a vast space of 10141 genotypes (instruction sequences), which can form 512 different phenotypes. These phenotypes are distinguished by different Boolean logic functions they can compute, as well as by the complexity of these functions. We observe several properties with parallels in natural systems, such as connected genotype networks and asymmetric phenotypic transitions. The likely common cause is robustness to genotypic change. We describe an intriguing tension between phenotypic complexity and evolvability that may have implications for biological evolution. On the one hand, genotypic change is more likely to yield novel phenotypes in more complex organisms. On the other hand, the total number of novel phenotypes reachable through genotypic change is highest for organisms with simple phenotypes. Artificial evolving systems can help us study aspects of biological evolvability that are not accessible in vastly more complex natural systems. They can also help identify properties, such as robustness, that are required for both human-designed artificial systems and synthetic biological systems to be evolvable.

The genotype-phenotype map of an evolving digital organism

PubMed Central

Zaman, Luis; Wagner, Andreas

2017-01-01

To understand how evolving systems bring forth novel and useful phenotypes, it is essential to understand the relationship between genotypic and phenotypic change. Artificial evolving systems can help us understand whether the genotype-phenotype maps of natural evolving systems are highly unusual, and it may help create evolvable artificial systems. Here we characterize the genotype-phenotype map of digital organisms in Avida, a platform for digital evolution. We consider digital organisms from a vast space of 10141 genotypes (instruction sequences), which can form 512 different phenotypes. These phenotypes are distinguished by different Boolean logic functions they can compute, as well as by the complexity of these functions. We observe several properties with parallels in natural systems, such as connected genotype networks and asymmetric phenotypic transitions. The likely common cause is robustness to genotypic change. We describe an intriguing tension between phenotypic complexity and evolvability that may have implications for biological evolution. On the one hand, genotypic change is more likely to yield novel phenotypes in more complex organisms. On the other hand, the total number of novel phenotypes reachable through genotypic change is highest for organisms with simple phenotypes. Artificial evolving systems can help us study aspects of biological evolvability that are not accessible in vastly more complex natural systems. They can also help identify properties, such as robustness, that are required for both human-designed artificial systems and synthetic biological systems to be evolvable. PMID:28241039

Huntington's Disease: Relationship Between Phenotype and Genotype.

PubMed

Sun, Yi-Min; Zhang, Yan-Bin; Wu, Zhi-Ying

2017-01-01

Huntington's disease (HD) is an autosomal dominant inherited neurodegenerative disease with the typical manifestations of involuntary movements, psychiatric and behavior disorders, and cognitive impairment. It is caused by the dynamic mutation in CAG triplet repeat number in exon 1 of huntingtin (HTT) gene. The symptoms of HD especially the age at onset are related to the genetic characteristics, both the CAG triplet repeat and the modified factors. Here, we reviewed the recent advancement on the genotype-phenotype relationship of HD, mainly focus on the characteristics of different expanded CAG repeat number, genetic modifiers, and CCG repeat number in the 3' end of CAG triplet repeat and their effects on the phenotype. We also reviewed the special forms of HD (juvenile HD, atypical onset HD, and homozygous HD) and their phenotype-genotype correlations. The review will aid clinicians to predict the onset age and disease course of HD, give the genetic counseling, and accelerate research into the HD mechanism.

Cone opsins, colour blindness and cone dystrophy: Genotype-phenotype correlations.

PubMed

Gardner, J C; Michaelides, M; Hardcastle, A J

2016-05-25

X-linked cone photoreceptor disorders caused by mutations in the OPN1LW (L) and OPN1MW (M) cone opsin genes on chromosome Xq28 include a range of conditions from mild stable red-green colour vision deficiencies to severe cone dystrophies causing progressive loss of vision and blindness. Advances in molecular genotyping and functional analyses of causative variants, combined with deep retinal phenotyping, are unravelling genetic mechanisms underlying the variability of cone opsin disorders.

Clinical and genetic features of the patients with X-Linked agammaglobulinemia from Turkey: Single-centre experience.

PubMed

Esenboga, S; Cagdas, D; Ozgur, T T; Gur Cetinkaya, P; Turkdemir, L M; Sanal, O; VanDerBurg, M; Tezcan, I

2018-03-01

X-linked agammaglobulinemia is a primary immunodeficiency disorder resulting from BTK gene mutations. There are many studies in the literature suggesting contradictory ideas about phenotype-genotype correlation. The aim of this study was to identify the mutations and clinical findings of patients with XLA in Turkey, to determine long-term complications related to the disease and to analyse the phenotype-genotype correlation. Thirty-two patients with XLA diagnosed between 1985 and 2016 in Pediatric Immunology Department of Hacettepe University Ihsan Dogramaci Children's Hospital were investigated. A clinical survey including clinical features of the patients was completed, and thirty-two patients from 26 different families were included in the study. Getting early diagnosis and regular assessment with imaging techniques seem to be the most important issues for improving the health status of the patients with XLA. Early molecular analysis gives chance for definitive diagnosis and genetic counselling, but not for predicting the clinical severity and prognosis. © 2018 The Foundation for the Scandinavian Journal of Immunology.

An Adaptive Association Test for Multiple Phenotypes with GWAS Summary Statistics.

PubMed

Kim, Junghi; Bai, Yun; Pan, Wei

2015-12-01

We study the problem of testing for single marker-multiple phenotype associations based on genome-wide association study (GWAS) summary statistics without access to individual-level genotype and phenotype data. For most published GWASs, because obtaining summary data is substantially easier than accessing individual-level phenotype and genotype data, while often multiple correlated traits have been collected, the problem studied here has become increasingly important. We propose a powerful adaptive test and compare its performance with some existing tests. We illustrate its applications to analyses of a meta-analyzed GWAS dataset with three blood lipid traits and another with sex-stratified anthropometric traits, and further demonstrate its potential power gain over some existing methods through realistic simulation studies. We start from the situation with only one set of (possibly meta-analyzed) genome-wide summary statistics, then extend the method to meta-analysis of multiple sets of genome-wide summary statistics, each from one GWAS. We expect the proposed test to be useful in practice as more powerful than or complementary to existing methods. © 2015 WILEY PERIODICALS, INC.

Duchenne/Becker muscular dystrophy: correlation of phenotype by electroretinography with sites of dystrophin mutations.

PubMed

Pillers, D A; Fitzgerald, K M; Duncan, N M; Rash, S M; White, R A; Dwinnell, S J; Powell, B R; Schnur, R E; Ray, P N; Cibis, G W; Weleber, R G

1999-01-01

The dark-adapted electroretinogram (ERG) of patients with Duchenne and Becker muscular dystrophy (DMD/BMD) shows a marked reduction in b-wave amplitude. Genotype-phenotype studies of mouse models for DMD show position-specific effects of the mutations upon the phenotype: mice with 5' defects of dystrophin have normal ERGs, those with defects in the central region have a normal b-wave amplitude associated with prolonged implicit times for both the b-wave and oscillatory potentials, and mice with 3' defects have a phenotype similar to that seen in DMD/BMD patients. The mouse studies suggest a key role for the carboxyl terminal dystrophin isoform, Dp260, in retinal electrophysiology. We have undertaken a systematic evaluation of DMD/BMD patients through clinical examination and review of the literature in order to determine whether the position-specific effects of mutations noted in the mouse are present in man. We have found that, in man, a wider variation of DMD defects correlate with reductions in the b-wave amplitude. Individuals with normal ERGs have mutations predominantly located 5' of the transcript initiation site of Dp260. Our results suggest that the most important determinant in the ERG b-wave phenotype is the mutation position, rather than muscle disease severity. Forty-six per cent of patients with mutations 5' of the Dp260 transcript start site have abnormal ERGs, as opposed to 94% with more distal mutations. The human genotype-phenotype correlations are consistent with a role for Dp260 in normal retinal electrophysiology and may also reflect the expression of other C-terminal dystrophin isoforms and their contributions to retinal signal transmission.

Epilepsy may be the major risk factor of mental retardation in children with tuberous sclerosis: A retrospective cohort study.

PubMed

Wang, Yang-Yang; Pang, Ling-Yu; Ma, Shu-Fang; Zhang, Meng-Na; Liu, Li-Ying; Zou, Li-Ping

2017-12-01

Mental retardation (MR) is one of the most common cognitive comorbidities in children with tuberous sclerosis, and there are enormous studies about its risk factors. The genetic difference and the severity of epilepsy are the two main factors, but their weight in the occurrence of MR is still unclear. Two hundred twenty-three patients with tuberous sclerosis who received intelligence assessment, genetic mutation analysis, and the epilepsy severity assessment were included in our study. Genotype-neurocognitive phenotype correlations and epilepsy-neurocognitive phenotype correlations were analyzed by binary logistic regression analysis. No statistical significant result was found on genotype-neurocognitive phenotype correlations, which contrasted the previous report. The prevalence of MR was 50.0% for the patients with tuberous sclerosis complex-1 (TSC1) mutation, 54.5% for TSC2 (p=0.561), 54.7% for patients with protein-truncating (PT) and 50.0% for patients with nontruncating (NT) (p=0.791), and 54.3% for patients with family history and 53.7% for patients without family history (p=0.748). Statistical significant results were found on epilepsy-neurocognitive phenotype correlations, both on E-chess score (p=0.01) and the occurrence of infantile spasms (p=0.014), which was consistent to the previous study. For children with tuberous sclerosis, instead of genetic factors, epilepsy may play the main role for the presence of mental retardation. Patients with mental retardation tend to have earlier seizure attack, take more AEDs, have more seizure types, and have higher seizure frequency. Among the four cognitive functions in Denver II, social ability and language ability are more vulnerable to be influenced than fine and gross motor ability. Copyright © 2017 Elsevier Inc. All rights reserved.

Discovering the desirable alleles contributing to the lignocellulosic biomass traits in saccharum germplasm collections for energy cane improvement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Todd, James; Comstock, Jack C.

Phenotyping Methods: The accessions (which includes 21 taxa and 1,177 accessions) in the World Collection of Sugarcane and Related Grasses (WCSRG) was evaluated for the following traits: arenchyma, internode length and diameter, pubescence, pith, Brix, stalk number and fiber. A core of 300 accessions that included each species in the World Collection was selected by using the Maximization Strategy in MStrat software. Results: The core had a higher diversity rating than random selections of 300 accessions. The Shannon–Weaver Diversity Index scores of the core and whole collection were similar indicating that the majority of the diversity was captured by themore » core collection. The ranges and medians between the core and WCSRG were similar; only two of the trait medians were not significant at P = 0.05 using the non-parametric Wilcoxon method and the coincidence rate (CR % = 96.2) was high (>80) indicating that extreme values were retained. Thus, the phenotypic diversity of these traits in the WCSRG was well represented by the core collection. Associations Methods: Genotypic and phenotypic data were collected for 1002 accessions of the WCSRG including 209 SSR markers. Association analysis was performed using both General Linear (GLM) and Maximum Likelihood (MLM) models. Different core collections with 300 accessions each were selected based on genotypic, phenotypic and combined data based on the Maximization Strategy in MStrat software. Results: A major portion of the genotyping involving SNPs is being conducted by Dr. Jianping Wang of the University of Florida under the DOE award DE-FG 02-11ER 65214 and the genotypic and phenotypic associations will be reported separately next year. In the current, study forty one and seventeen markers were found to be associated with traits using the GLM and MLM methods respectively including associations with arenchyma, internode length and diameter, pubescence, pith, and Sugar Cane Yellow Leaf Virus. The data indicates that each of the cores and the World Collection are similar to each other genotypically and phenotypically, but the core that was selected using only genotypic data was significantly different phenotypically. This indicates that there is not enough association between the genotypic and phenotypic diversity as to select using only genotypic diversity and get the full phenotypic diversity. Core Collection: Creation and Phenotyping Methods: To evaluate this germplasm for breeding purposes, a representative diversity panel selected from the WCSRG of approximately 300 accessions was planted at Canal Point, FL in three replications. These accessions were measured for stalk height and stalk number multiple times throughout the growing season and Brix and fresh biomass during harvest in 2013 and, stalk height, stalk number, stalk diameter, internode length, Brix and fresh and dry biomass was determined in the ratoon crop harvest in 2014. Results: In correlations of multiple measurements, there were higher correlations for early measurements of stalk number and stalk height with harvest traits like Brix and fresh weight. Hybrids had higher fresh mass and Brix while Saccharum spontaneum had higher stalk number and dry mass. The heritability of hybrid mass traits was lower in the ratoon crop. According to the principal component analysis, the diversity panel was divided into two groups. One group had accessions with high stalk number and high dry biomass like S. spontaneum and the other groups contained accessions with higher Brix and fresh biomass like S. officinarum. Mass traits correlated with each other as expected but hybrids had lower correlations between fresh and dry mass. Stalk number and the mass traits correlated with each other except in S. spontaneum and hybrids in the first ratoon. There were 110 accessions not significantly different in Brix from the commercial sugarcane checks including 10 S. spontaneum accessions. There were 27 dry and 6 fresh mass accessions significantly higher than the commercial sugarcane checks. Core Collection: Fiber analysis Methods: A biomass sample was taken from each accession then shredded and dried. Fiber analysis was then performed on each sample. The acetyl groups, acid insoluble lignin, acid soluble lignin, arabinan, glucan, holocellulose, total lignin, structural ash, and xylan were quantified on a % fiber basis and nonstructural ash on a % total basis. Results: There were significant, but not large differences between species for holocellulose, lignin, acetyl, acid soluble lignin, nonstructural ash, and glucan. For each trait, S. spontaneum had significantly more holocellulose, glucan, lignin, and nonstructural ash and less acetyl and acid soluble lignin than the other species. In all populations, glucan and was positively correlated with holocellulose were positively correlated and glucan and and holocellulose were negatively correlated with lignin. In hybrids, internode length correlated positively with holocellulose and nonstructural ash and negatively with lignin. The heritability estimates for each of the fiber component traits is low indicating that environment is an important factor in fiber composition. Principal component analysis indicated that a large amount of diversity exists within each of the species.« less

Molecular epidemiology and clinical characteristics of drug-resistant Mycobacterium tuberculosis in a tuberculosis referral hospital in China.

PubMed

Wang, Qi; Lau, Susanna K P; Liu, Fei; Zhao, Yanlin; Li, Hong Min; Li, Bing Xi; Hu, Yong Liang; Woo, Patrick C Y; Liu, Cui Hua

2014-01-01

Despite the large number of drug-resistant tuberculosis (TB) cases in China, few studies have comprehensively analyzed the drug resistance-associated gene mutations and genotypes in relation to the clinical characteristics of M. tuberculosis (Mtb) isolates. We thus analyzed the phenotypic and genotypic drug resistance profiles of 115 Mtb clinical isolates recovered from a tuberculosis referral hospital in Beijing, China. We also performed genotyping by 28 loci MIRU-VNTR analysis. Socio-demographic and clinical data were retrieved from medical records and analyzed. In total, 78 types of mutations (including 42 previously reported and 36 newly identified ones) were identified in 115 Mtb clinical isolates. There was significant correlation between phenotypic and genotypic drug resistance rates for first-line anti-TB drugs (P<0.001). Genotyping revealed 101 MIRU-VNTR types, with 20 isolates (17.4%) being clustered and 95 isolates (82.6%) having unique genotypes. Higher proportion of re-treatment cases was observed among patients with clustered isolates than those with unique MIRU-VNTR genotypes (75.0% vs. 41.1%). Moreover, clinical epidemiological links were identified among patients infected by Mtb strains belonging to the same clusters, suggesting a potential of transmission among patients. Our study provided information on novel potential drug resistance-associated mutations in Mtb. In addition, the genotyping data from our study suggested that enforcement of the implementation of genotyping in diagnostic routines would provide important information for better monitor and control of TB transmission.

Genotype and phenotype correlation in von Hippel-Lindau disease based on alteration of the HIF-α binding site in VHL protein.

PubMed

Liu, Sheng-Jie; Wang, Jiang-Yi; Peng, Shuang-He; Li, Teng; Ning, Xiang-Hui; Hong, Bao-An; Liu, Jia-Yuan; Wu, Peng-Jie; Zhou, Bo-Wen; Zhou, Jing-Cheng; Qi, Nie-Nie; Peng, Xiang; Zhang, Jiu-Feng; Ma, Kai-Fang; Cai, Lin; Gong, Kan

2018-03-29

PurposeVon Hippel-Lindau (VHL) disease is a rare hereditary cancer syndrome that reduces life expectancy. We aimed to construct a more valuable genotype-phenotype correlation based on alterations in VHL protein (pVHL).MethodsVHL patients (n = 339) were recruited and grouped based on mutation types: HIF-α binding site missense (HM) mutations, non-HIF-α binding site missense (nHM) mutations, and truncating (TR) mutations. Age-related risks of VHL-associated tumors and patient survival were compared.ResultsMissense mutations conferred an increased risk of pheochromocytoma (HR = 1.854, p = 0.047) compared with truncating mutations. The risk of pheochromocytoma was lower in the HM group than in the nHM group (HR = 0.298, p = 0.003) but was similar between HM and TR groups (HR = 0.901, p = 0.810). Patients in the nHM group had a higher risk of pheochromocytoma (HR = 3.447, p < 0.001) and lower risks of central nervous system hemangioblastoma (CHB) (HR = 0.700, p = 0.045), renal cell carcinoma (HR = 0.610, p = 0.024), and pancreatic tumor (HR = 0.382, p < 0.001) than those in the combined HM and TR (HMTR) group. Moreover, nHM mutations were independently associated with better overall survival (HR = 0.345, p = 0.005) and CHB-specific survival (HR = 0.129, p = 0.005) than HMTR mutations.ConclusionThe modified genotype-phenotype correlation links VHL gene mutation, substrate binding site, and phenotypic diversity (penetrance and survival), and provides more accurate information for genetic counseling and pathogenesis studies.Genetics in Medicine advance online publication, 29 March 2018; doi:10.1038/gim.2017.261.

eCOMPAGT – efficient Combination and Management of Phenotypes and Genotypes for Genetic Epidemiology

PubMed Central

Schönherr, Sebastian; Weißensteiner, Hansi; Coassin, Stefan; Specht, Günther; Kronenberg, Florian; Brandstätter, Anita

2009-01-01

Background High-throughput genotyping and phenotyping projects of large epidemiological study populations require sophisticated laboratory information management systems. Most epidemiological studies include subject-related personal information, which needs to be handled with care by following data privacy protection guidelines. In addition, genotyping core facilities handling cooperative projects require a straightforward solution to monitor the status and financial resources of the different projects. Description We developed a database system for an efficient combination and management of phenotypes and genotypes (eCOMPAGT) deriving from genetic epidemiological studies. eCOMPAGT securely stores and manages genotype and phenotype data and enables different user modes with different rights. Special attention was drawn on the import of data deriving from TaqMan and SNPlex genotyping assays. However, the database solution is adjustable to other genotyping systems by programming additional interfaces. Further important features are the scalability of the database and an export interface to statistical software. Conclusion eCOMPAGT can store, administer and connect phenotype data with all kinds of genotype data and is available as a downloadable version at . PMID:19432954

FY*X real-time polymerase chain reaction with melting curve analysis associated with a complete one-step real-time FY genotyping.

PubMed

Ansart-Pirenne, H; Martin-Blanc, S; Le Pennec, P-Y; Rouger, P; Cartron, J-P; Tournamille, C

2007-02-01

The Duffy (FY) blood group system is controlled by four major alleles: FY*A and FY*B, the Caucasian common alleles, encoding Fy(a) and Fy(b) antigens; FY*X allele responsible for a poorly expressed Fy(b) antigen, and FY*Fy a silent predominant allele among Black population. Despite the recent development of a real-time fluorescent polymerase chain reaction (PCR) method for FY genotyping FY*X genotyping has not been described by this method. This study focused on the real-time FY*X genotyping development associated with a complete, one-step real-time FY genotyping, based on fluorescence resonance energy transfer (FRET) technology. Seventy-two blood samples from Fy(a+b-) Caucasian blood donors were studied by real-time PCR only. Forty-seven Caucasian and Black individual blood samples, referred to our laboratory, were studied by PCR-RFLP and real-time PCR. For each individual, the result of the genotype was compared to the known phenotype. The FY*X allele frequency calculated in an Fy(a+b-) Caucasian blood donors population was 0.014. With the Caucasian and Black patient samples we found a complete correlation between PCR-RFLP and the real-time PCR method whatever the alleles combination tested. When the known phenotype was not correlated to FY*X genotype, the presence of the Fy(b) antigen was always confirmed by adsorption-elution. The real-time technology method is rapid and accurate for FY genotyping. From now, we are able to detect the FY*X allele in all the alleles combinations studied. Regarding its significant frequency, the detection of the FY*X allele is useful for the correct typing of blood donors and recipients considering the therapeutic use of blood units and the preparation of test red blood cells for antibody screening.

Higher risk of death among MEN1 patients with mutations in the JunD interacting domain: a Groupe d'etude des Tumeurs Endocrines (GTE) cohort study.

PubMed

Thevenon, Julien; Bourredjem, Abderrahmane; Faivre, Laurence; Cardot-Bauters, Catherine; Calender, Alain; Murat, Arnaud; Giraud, Sophie; Niccoli, Patricia; Odou, Marie-Françoise; Borson-Chazot, Françoise; Barlier, Anne; Lombard-Bohas, Catherine; Clauser, Eric; Tabarin, Antoine; Parfait, Béatrice; Chabre, Olivier; Castermans, Emilie; Beckers, Albert; Ruszniewski, Philippe; Le Bras, Morgane; Delemer, Brigitte; Bouchard, Philippe; Guilhem, Isabelle; Rohmer, Vincent; Goichot, Bernard; Caron, Philippe; Baudin, Eric; Chanson, Philippe; Groussin, Lionel; Du Boullay, Hélène; Weryha, Georges; Lecomte, Pierre; Penfornis, Alfred; Bihan, Hélène; Archambeaud, Françoise; Kerlan, Véronique; Duron, Françoise; Kuhn, Jean-Marc; Vergès, Bruno; Rodier, Michel; Renard, Michel; Sadoul, Jean-Louis; Binquet, Christine; Goudet, Pierre

2013-05-15

Multiple endocrine neoplasia syndrome type 1 (MEN1), which is secondary to mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Although genotype-phenotype studies have so far failed to identify any statistical correlations, some families harbor recurrent tumor patterns. The function of MENIN is unclear, but has been described through the discovery of its interacting partners. Mutations in the interacting domains of MENIN functional partners have been shown to directly alter its regulation abilities. We report on a cohort of MEN1 patients from the Groupe d'étude des Tumeurs Endocrines. Patients with a molecular diagnosis and a clinical follow-up, totaling 262 families and 806 patients, were included. Associations between mutation type, location or interacting factors of the MENIN protein and death as well as the occurrence of MEN1-related tumors were tested using a frailty Cox model to adjust for potential heterogeneity across families. Accounting for the heterogeneity across families, the overall risk of death was significantly higher when mutations affected the JunD interacting domain (adjusted HR = 1.88: 95%-CI = 1.15-3.07). Patients had a higher risk of death from cancers of the MEN1 spectrum (HR = 2.34; 95%-CI = 1.23-4.43). This genotype-phenotype correlation study confirmed the lack of direct genotype-phenotype correlations. However, patients with mutations affecting the JunD interacting domain had a higher risk of death secondary to a MEN1 tumor and should thus be considered for surgical indications, genetic counseling and follow-up.

Defining a Contemporary Ischemic Heart Disease Genetic Risk Profile Using Historical Data.

PubMed

Mosley, Jonathan D; van Driest, Sara L; Wells, Quinn S; Shaffer, Christian M; Edwards, Todd L; Bastarache, Lisa; McCarty, Catherine A; Thompson, Will; Chute, Christopher G; Jarvik, Gail P; Crosslin, David R; Larson, Eric B; Kullo, Iftikhar J; Pacheco, Jennifer A; Peissig, Peggy L; Brilliant, Murray H; Linneman, James G; Denny, Josh C; Roden, Dan M

2016-12-01

Continued reductions in morbidity and mortality attributable to ischemic heart disease (IHD) require an understanding of the changing epidemiology of this disease. We hypothesized that we could use genetic correlations, which quantify the shared genetic architectures of phenotype pairs and extant risk factors from a historical prospective study to define the risk profile of a contemporary IHD phenotype. We used 37 phenotypes measured in the ARIC study (Atherosclerosis Risk in Communities; n=7716, European ancestry subjects) and clinical diagnoses from an electronic health record (EHR) data set (n=19 093). All subjects had genome-wide single-nucleotide polymorphism genotyping. We measured pairwise genetic correlations (rG) between the ARIC and EHR phenotypes using linear mixed models. The genetic correlation estimates between the ARIC risk factors and the EHR IHD were modestly linearly correlated with hazards ratio estimates for incident IHD in ARIC (Pearson correlation [r]=0.62), indicating that the 2 IHD phenotypes had differing risk profiles. For comparison, this correlation was 0.80 when comparing EHR and ARIC type 2 diabetes mellitus phenotypes. The EHR IHD phenotype was most strongly correlated with ARIC metabolic phenotypes, including total:high-density lipoprotein cholesterol ratio (rG=-0.44, P=0.005), high-density lipoprotein (rG=-0.48, P=0.005), systolic blood pressure (rG=0.44, P=0.02), and triglycerides (rG=0.38, P=0.02). EHR phenotypes related to type 2 diabetes mellitus, atherosclerotic, and hypertensive diseases were also genetically correlated with these ARIC risk factors. The EHR IHD risk profile differed from ARIC and indicates that treatment and prevention efforts in this population should target hypertensive and metabolic disease. © 2016 American Heart Association, Inc.

Genotype-Phenotype Correlation in 153 Adult Patients With Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency: Analysis of the United Kingdom Congenital Adrenal Hyperplasia Adult Study Executive (CaHASE) Cohort

PubMed Central

Krone, Nils; Rose, Ian T.; Willis, Debbie S.; Hodson, James; Wild, Sarah H.; Doherty, Emma J.; Hahner, Stefanie; Parajes, Silvia; Stimson, Roland H.; Han, Thang S.; Carroll, Paul V.; Conway, Gerry S.; Walker, Brian R.; MacDonald, Fiona; Arlt, Wiebke

2013-01-01

Context: In congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, a strong genotype-phenotype correlation exists in childhood. However, similar data in adults are lacking. Objective: The objective of the study was to test whether the severity of disease-causing CYP21A2 mutations influences the treatment and health status in adults with CAH. Research Design and Methods: We analyzed the genotype in correlation with treatment and health status in 153 adults with CAH from the United Kingdom Congenital adrenal Hyperplasia Adult Study Executive cohort. Results: CYP21A2 mutations were distributed similarly to previously reported case series. In 7 patients a mutation was identified on only 1 allele. Novel mutations were detected on 1.7% of alleles (5 of 306). Rare mutations were found on 2.3% of alleles (7 of 306). For further analysis, patients were categorized into CYP21A2 mutation groups according to predicted residual enzyme function: null (n = 34), A (n = 42), B (n = 36), C (n = 34), and D (n = 7). Daily glucocorticoid dose was highest in group null and lowest in group C. Fludrocortisone was used more frequently in patients with more severe genotypes. Except for lower female height in group B, no statistically significant associations between genotype and clinical parameters were found. Androgens, blood pressure, lipids, blood glucose, and homeostasis model assessment of insulin resistance were not different between groups. Subjective health status was similarly impaired across groups. Conclusions: In adults with classic CAH and women with nonclassic CAH, there was a weak association between genotype and treatment, but health outcomes were not associated with genotype. The underrepresentation of males with nonclassic CAH may reflect that milder genotypes result in a milder condition that is neither diagnosed nor followed up in adulthood. Overall, our results suggest that the impaired health status of adults with CAH coming to medical attention is acquired rather than genetically determined and therefore could potentially be improved through modification of treatment. PMID:23337727

Phenotype-genotype correlations in a series of wolfram syndrome families.

PubMed

Smith, Casey J A; Crock, Patricia A; King, Bruce R; Meldrum, Cliff J; Scott, Rodney J

2004-08-01

Wolfram syndrome is an extremely rare autosomal-recessive disorder that predisposes the development of type 1 diabetes in association with progressive optic atrophy. The genetic basis of this disease has been shown to be due to mutations in the WFS1 gene. The WFS1 gene encodes a novel transmembrane protein called wolframin, which recent evidence suggests may serve as a novel endoplasmic reticulum calcium channel in pancreatic beta-cells and neurons. Genotype-phenotype correlations in this syndrome are becoming apparent and may help in explaining some of the variable characteristics observed in this disease. In this report, we have studied 13 patients with Wolfram syndrome from nine families to further define the relationship between mutation site and type with specific disease characteristics. A severe phenotype was seen in patients with mutations in exon 4 and with a large deletion encompassing most of exon 8. In total, nine novel mutations were identified as well as three new silent polymorphisms. Similar to all other mutation reports, most causative changes identified in the WFS1 gene occurred in exon 8, and only one was identified outside this region in exon 4.

Aluminum exclusion from root zone and maintenance of nutrient uptake are principal mechanisms of Al tolerance in Pisum sativum L.

PubMed

Kichigina, Natalia E; Puhalsky, Jan V; Shaposhnikov, Aleksander I; Azarova, Tatiana S; Makarova, Natalia M; Loskutov, Svyatoslav I; Safronova, Vera I; Tikhonovich, Igor A; Vishnyakova, Margarita A; Semenova, Elena V; Kosareva, Irina A; Belimov, Andrey A

2017-10-01

Our study aimed to evaluate intraspecific variability of pea ( Pisum sativum L.) in Al tolerance and to reveal mechanisms underlying genotypic differences in this trait. At the first stage, 106 pea genotypes were screened for Al tolerance using root re-elongation assay based on staining with eriochrome cyanine R. The root re-elongation zone varied from 0.5 mm to 14 mm and relationships between Al tolerance and provenance or phenotypic traits of genotypes were found. Tolerance index (TI), calculated as a biomass ratio of Al-treated and non-treated contrasting genotypes grown in hydroponics for 10 days, varied from 30% to 92% for roots and from 38% to 90% for shoots. TI did not correlate with root or shoot Al content, but correlated positively with increasing pH and negatively with residual Al concentration in nutrient solution in the end of experiments. Root exudation of organic acid anions (mostly acetate, citrate, lactate, pyroglutamate, pyruvate and succinate) significantly increased in several Al-treated genotypes, but did not correlate with TI. Al-treatment decreased Ca, Co, Cu, K, Mg, Mn, Mo, Ni, S and Zn contents in roots and/or shoots, whereas contents of several elements (P, B, Fe and Mo in roots and B and Fe in shoots) increased, suggesting that Al toxicity induced substantial disturbances in uptake and translocation of nutrients. Nutritional disturbances were more pronounced in Al sensitive genotypes. In conclusion, pea has a high intraspecific variability in Al tolerance and this trait is associated with provenance and phenotypic properties of plants. Transformation of Al to unavailable (insoluble) forms in the root zone and the ability to maintain nutrient uptake are considered to be important mechanisms of Al tolerance in this plant species.

Common variant rs356182 near SNCA defines a Parkinson's disease endophenotype.

PubMed

Cooper, Christine A; Jain, Nimansha; Gallagher, Michael D; Weintraub, Daniel; Xie, Sharon X; Berlyand, Yosef; Espay, Alberto J; Quinn, Joseph; Edwards, Karen L; Montine, Thomas; Van Deerlin, Vivianna M; Trojanowski, John; Zabetian, Cyrus P; Chen-Plotkin, Alice S

2017-01-01

Parkinson's disease (PD) presents clinically with several motor subtypes that exhibit variable treatment response and prognosis. Here, we investigated genetic variants for their potential association with PD motor phenotype and progression. We screened 10 SNPs, previously associated with PD risk, for association with tremor-dominant (TD) versus postural-instability gait disorder (PIGD) motor subtypes. SNPs that correlated with the TD/PIGD ratio in a discovery cohort of 251 PD patients were then evaluated in a multi-site replication cohort of 559 PD patients. SNPs associated with motor phenotype in both cross-sectional cohorts were next evaluated for association with (1) rates of motor progression in a longitudinal subgroup of 230 PD patients and (2) brain alpha-synuclein ( SNCA ) expression in the GTEx (Genotype-Tissue Expression project) consortium database. Genotype at rs356182, near SNCA , correlated with the TD/PIGD ratio in both the discovery (Bonferroni-corrected P = 0.04) and replication cohorts ( P = 0.02). The rs356182 GG genotype was associated with a more tremor-predominant phenotype and predicted a slower rate of motor progression (1-point difference in annual rate of UPDRS-III motor score change, P = 0.01). The rs356182 genotype was associated with SNCA expression in the cerebellum ( P = 0.005). Our study demonstrates that the GG genotype at rs356182 provides molecular definition for a clinically important endophenotype associated with (1) more tremor-predominant motor phenomenology, (2) slower rates of motor progression, and (3) decreased brain expression of SNCA . Such molecularly defined endophenotyping in PD may benefit both clinical trial design and tailoring of clinical care as we enter the era of precision medicine.

A novel KCNQ4 one-base deletion in a large pedigree with hearing loss: implication for the genotype-phenotype correlation.

PubMed

Kamada, Fumiaki; Kure, Shigeo; Kudo, Takayuki; Suzuki, Yoichi; Oshima, Takeshi; Ichinohe, Akiko; Kojima, Kanako; Niihori, Tetsuya; Kanno, Junko; Narumi, Yoko; Narisawa, Ayumi; Kato, Kumi; Aoki, Yoko; Ikeda, Katsuhisa; Kobayashi, Toshimitsu; Matsubara, Yoichi

2006-01-01

Autosomal-dominant, nonsyndromic hearing impairment is clinically and genetically heterogeneous. We encountered a large Japanese pedigree in which nonsyndromic hearing loss was inherited in an autosomal-dominant fashion. A genome-wide linkage study indicated linkage to the DFNA2 locus on chromosome 1p34. Mutational analysis of KCNQ4 encoding a potassium channel revealed a novel one-base deletion in exon 1, c.211delC, which generated a profoundly truncated protein without transmembrane domains (p.Q71fsX138). Previously, six missense mutations and one 13-base deletion, c.211_223del, had been reported in KCNQ4. Patients with the KCNQ4 missense mutations had younger-onset and more profound hearing loss than patients with the 211_223del mutation. In our current study, 12 individuals with the c.211delC mutation manifested late-onset and pure high-frequency hearing loss. Our results support the genotype-phenotype correlation that the KCNQ4 deletions are associated with later-onset and milder hearing impairment than the missense mutations. The phenotypic difference may be caused by the difference in pathogenic mechanisms: haploinsufficiency in deletions and dominant-negative effect in missense mutations.

Studies on N-Acetyltransferase (NAT2) Genotype Relationships in Emiratis: Confirmation of the Existence of Phenotype Variation among Slow Acetylators.

PubMed

Al-Ahmad, Mohammad M; Amir, Naheed; Dhanasekaran, Subramanian; John, Anne; Abdulrazzaq, Yousef M; Ali, Bassam R; Bastaki, Salim

2017-09-01

Individuals with slow N-acetylation phenotype often experience toxicity from drugs such as isoniazid, sulfonamides, procainamide, and hydralazine, whereas rapid acetylators may not respond to these medications. The highly polymorphic N-acetyltransferase 2 enzyme encoded by the NAT2 gene is one of the N-acetylators in humans with a clear impact on the metabolism of a significant number of important drugs. However, there are limited studies on N-acetylation phenotypes and NAT2 genotypes among Emiratis, and thus this study was carried out to fill this gap. Five hundred seventy-six Emirati subjects were asked to consume a soft drink containing caffeine (a nontoxic and reliable probe for predicting the acetylation phenotype) and then provide a buccal swab along with a spot urine sample. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the genotype of each individual. Phenotyping was carried out by analyzing the caffeine metabolites using high-performance liquid chromatography (HPLC) analysis. We found that 78.5%, 19.1%, and 2.4% of the Emirati subjects were slow, intermediate, and rapid acetylators, respectively. In addition, we found that 77.4% of the subjects were homozygous or heterozygous for two nonreference alleles, whereas 18.4% and 4.2% were heterozygous or homozygous for the reference allele (NAT2*4), respectively. The most common genotypes found were NAT2*5B/*7B, NAT2*5B/*6A, NAT2*7B/*14B, and NAT2*4/*5B, with frequencies of 0.255, 0.135, 0.105, and 0.09, respectively. The degree of phenotype/genotype concordance was 96.2%. The NAT2*6A/*6A, NAT2*6A/*7B, NAT2*7B/*7B, and NAT2*5A/*5B genotypes were found to be associated with the lowest 5-acetylamino-6-formylamino-3-methyluracil/1-methylxanthine (AFMU/1X) ratios. There is a high percentage of slow acetylators among Emiratis, which correlates with the presence of nonreference alleles for the NAT2 gene. Individuals who carried NAT2*6A/*6A, NAT2*6A/*7B, NAT2*7B/*7B, or NAT2*5A/*5B genotypes might be at higher risk of toxicity with some drugs and some diseases compared to others, as these genotypes are associated with the slowest acetylation status. © 2017 John Wiley & Sons Ltd/University College London.

3D Laser Triangulation for Plant Phenotyping in Challenging Environments

PubMed Central

Kjaer, Katrine Heinsvig; Ottosen, Carl-Otto

2015-01-01

To increase the understanding of how the plant phenotype is formed by genotype and environmental interactions, simple and robust high-throughput plant phenotyping methods should be developed and considered. This would not only broaden the application range of phenotyping in the plant research community, but also increase the ability for researchers to study plants in their natural environments. By studying plants in their natural environment in high temporal resolution, more knowledge on how multiple stresses interact in defining the plant phenotype could lead to a better understanding of the interaction between plant responses and epigenetic regulation. In the present paper, we evaluate a commercial 3D NIR-laser scanner (PlantEye, Phenospex B.V., Herleen, The Netherlands) to track daily changes in plant growth with high precision in challenging environments. Firstly, we demonstrate that the NIR laser beam of the scanner does not affect plant photosynthetic performance. Secondly, we demonstrate that it is possible to estimate phenotypic variation amongst the growth pattern of ten genotypes of Brassica napus L. (rapeseed), using a simple linear correlation between scanned parameters and destructive growth measurements. Our results demonstrate the high potential of 3D laser triangulation for simple measurements of phenotypic variation in challenging environments and in a high temporal resolution. PMID:26066990

Investigating genotype-phenotype relationships in Rett syndrome using an international data set.

PubMed

Bebbington, A; Anderson, A; Ravine, D; Fyfe, S; Pineda, M; de Klerk, N; Ben-Zeev, B; Yatawara, N; Percy, A; Kaufmann, W E; Leonard, H

2008-03-11

Rett syndrome is an uncommon neurodevelopmental disorder with an incidence of 1:9,000 live female births. The principal genetic cause was first reported in 1999 when the association with mutations in the methyl-CpG-binding protein 2 (or MECP2) gene was identified. This study uses data from a large international database, InterRett, to examine genotype-phenotype relationships and compares these with previous findings in a population-based cohort. The data set for these analyses was derived from a subset of InterRett cases with subject information collected from the family, the clinician, or both. Individual phenotypic characteristics and clinical severity using three scales were compared among those with eight known recurrent pathogenic MECP2 mutations as well as those with C-terminal deletions (n = 272). Overall, p.R270X and p.R255X were the most severe and p.R133C and p.R294X were the mildest mutations. Significant differences by mutation were seen for individual phenotypic characteristics such as hand use, ambulation, and language. This multicenter investigation into the phenotypic correlates of MECP2 mutations in Rett syndrome has provided a greater depth of understanding than hitherto available about the specific phenotypic characteristics associated with commonly occurring mutations. Although the modifying influence of X inactivation on clinical severity could not be included in the analysis, the findings confirm clear genotype-phenotype relationships in Rett syndrome and show the benefits of collaboration crucial to effective research in rare disorders.

Phenotypic and genotypic data integration and exploration through a web-service architecture.

PubMed

Nuzzo, Angelo; Riva, Alberto; Bellazzi, Riccardo

2009-10-15

Linking genotypic and phenotypic information is one of the greatest challenges of current genetics research. The definition of an Information Technology infrastructure to support this kind of studies, and in particular studies aimed at the analysis of complex traits, which require the definition of multifaceted phenotypes and the integration genotypic information to discover the most prevalent diseases, is a paradigmatic goal of Biomedical Informatics. This paper describes the use of Information Technology methods and tools to develop a system for the management, inspection and integration of phenotypic and genotypic data. We present the design and architecture of the Phenotype Miner, a software system able to flexibly manage phenotypic information, and its extended functionalities to retrieve genotype information from external repositories and to relate it to phenotypic data. For this purpose we developed a module to allow customized data upload by the user and a SOAP-based communications layer to retrieve data from existing biomedical knowledge management tools. In this paper we also demonstrate the system functionality by an example application of the system in which we analyze two related genomic datasets. In this paper we show how a comprehensive, integrated and automated workbench for genotype and phenotype integration can facilitate and improve the hypothesis generation process underlying modern genetic studies.

Interactive effects of genotype x environment on the live weight of GIFT Nile tilapias.

PubMed

Oliveira, Sheila N DE; Ribeiro, Ricardo P; Oliveira, Carlos A L DE; Alexandre, Luiz; Oliveira, Aline M S; Lopera-Barrero, Nelson M; Santander, Victor F A; Santana, Renan A C

2017-01-01

In this paper, the existence of a genotype x environment interaction for the average daily weight in GIFT Nile tilapia (Oreochromis niloticus) in different regions in the state of Paraná (Brazil) was analyzed. The heritability results were high in the uni-characteristic analysis: 0.71, 0.72 and 0.67 for the cities of Palotina (PL), Floriano (FL) and Diamond North (DN), respectively. Genetic correlations estimated in bivariate analyzes were weak with values between 0.12 for PL-FL, 0.06 for PL and 0.23 for DN-FL-DN. The Spearman correlation values were low, which indicated a change in ranking in the selection of animals in different environments in the study. There was heterogeneity in the phenotypic variance among the three regions and heterogeneity in the residual variance between PL and DN. The direct genetic gain was greater for the region with a DN value gain of 198.24 g/generation, followed by FL (98.73 g/generation) and finally PL (98.73 g/generation). The indirect genetic gains were lower than 0.37 and greater than 0.02 g/generation. The evidence of the genotype x environment interaction was verified, which indicated the phenotypic heterogeneity of the variances among the three regions, weak genetic correlation and modified rankings in the different environments.

Arylesterase Phenotype-Specific Positive Association Between Arylesterase Activity and Cholinesterase Specific Activity in Human Serum

PubMed Central

Aoki, Yutaka; Helzlsouer, Kathy J.; Strickland, Paul T.

2014-01-01

Context: Cholinesterase (ChE) specific activity is the ratio of ChE activity to ChE mass and, as a biomarker of exposure to cholinesterase inhibitors, has a potential advantage over simple ChE activity. Objective: To examine the association of several potential correlates (serum arylesterase/paraoxonase activity, serum albumin, sex, age, month of blood collection, and smoking) with plasma ChE specific activity. Methods: We analyzed data from 195 cancer-free controls from a nested case-control study, accounting for potential confounding. Results: Arylesterase activity had an independent, statistically significant positive association with ChE specific activity, and its magnitude was the greatest for the arylesterase phenotype corresponding to the QQ PON1192 genotype followed by phenotypes corresponding to QR and RR genotypes. Serum albumin was positively associated with ChE specific activity. Conclusions: Plasma arylesterase activity was positively associated with plasma ChE specific activity. This observation is consistent with protection conferred by a metabolic phenotype resulting in reduced internal dose. PMID:24473115

SNPs located at CpG sites modulate genome-epigenome interaction

USDA-ARS?s Scientific Manuscript database

DNA methylation is an important molecular-level phenotype that links genotypes and complex disease traits. Previous studies have found local correlation between genetic variants and DNA methylation levels (cis-meQTLs). However, general mechanisms underlying cis-meQTLs are unclear. We conducted a cis...

Audiological and vestibular features in affected subjects with USH3: a genotype/phenotype correlation.

PubMed

Sadeghi, Mehdi; Cohn, Edward S; Kimberling, William J; Tranebjaerg, Lisbeth; Möller, Claes

2005-05-01

The aims were to compare the genotype/phenotype relationship between USH3 mutations and the consequent hearing and vestibular phenotype; and to compare hearing loss (HL) progression between Usher syndrome types IB, IIA and USH3. Genetic, audiometric and vestibular examinations were performed in 28 subjects with USH3. Five different mutations in USH3 were identified. Severe HL was present from an early age (4 to 6 years) in 35% of subjects with USH3. Progression of HL begins in the first decade, and approximately 50% of subjects with USH3 become profoundly deaf by age 40. Various vestibular abnormalities were found in about half (10/22) of the tested subjects with USH3. Depending on the severity of HL, subjects with USH3 might be misdiagnosed as either Usher type IB or IIA. The results from this study can be used as discriminatory features in differential diagnosis of this syndrome.

More than two decades of Apc modeling in rodents

PubMed Central

Zeineldin, Maged; Neufeld, Kristi L.

2013-01-01

Mutation of tumor suppressor gene Adenomatous polyposis coli (APC) is an initiating step in most colon cancers. This review summarizes Apc models in mice and rats, with particular concentration on those most recently developed, phenotypic variation among different models, and genotype/ phenotype correlations. PMID:23333833

Molecular diagnosis of cystic fibrosis.

PubMed

Shrimpton, Antony E

2002-05-01

A review of the current molecular diagnosis of cystic fibrosis including an introduction to cystic fibrosis, the gene function, the phenotypic variation, who should be screened for which mutation, newborn and couple screening, quality assurance, phenotype-genotype correlation, methods and method limitations, options, statements, recommendations, useful Websites and treatments.

Genotype-phenotype correlations of dyshormonogenetic goiter in children and adolescents from South India

PubMed Central

Ramesh, Bangaraiah Gari; Bhargav, Panchangam Ramakanth; Rajesh, Bangaraiah Gari; Devi, Nangedda Vimala; Vijayaraghavan, Rajagopalan; Varma, Bhongir Aparna

2016-01-01

Background: Dyshormonogenetic goiter is one of the most common causes of hypothyroidism in children and adolescents in iodine nonendemic areas. The exact genotype-phenotypic correlations (GPCs) and risk categorization of hypothyroid phenotypes of dyshormonogenetic mutations are largely speculative. The genetic studies in pediatric dyshormonogenesis are very sparse from Indian sub-continent. In this context, we analyzed the implications of TPO, NIS, and DUOX2 gene mutations in hypothyroid children with dyshormonogenetic hypothyroidism (DH) from South India. Materials and Methods: This is interdisciplinary prospective study, we employed eight sets of primers and screened for 142 known single nucleotide polymorphisms in TPO, NIS, and DUOX2 genes. The subjects were children and adolescents with hypothyroidism due to dyshormonogenetic goiter. Congenital hypothyroidism, iodine deficiency, and Hashimoto's thyroiditis cases were excluded. Results: We detected nine mutations in 8/22 (36%) children. All the mutations were observed in the intronic regions of NIS gene and none in TPO or DUOX2 genes. Except for bi-allelic, synonymous polymorphism of TPO gene in child number 14, all other mutations were heterozygous in nature. GPCs show that our mutations significantly expressed the phenotypic traits such as overt hypothyroidism, goiter, and existence of family history. Other phenotypic characters such as sex predilection, the age of onset and transitory nature of hypothyroidism were not significantly affected by these mutations. Conclusion: NIS gene mutations alone appears to be most prevalent mutations in DH among South Indian children and these mutations significantly influenced phenotypic expressions such as severity of hypothyroidism, goiter rates, and familial clustering. PMID:27867886

Genotype and Phenotype Correlation in Hereditary Thrombotic Thrombocytopenic Purpura (Upshaw-Schulman Syndrome)

ClinicalTrials.gov

2018-02-12

Thrombotic Thrombocytopenic Purpura; Congenital Thrombotic Thrombocytopenic Purpura; Familial Thrombotic Thrombocytopenic Purpura; Thrombotic Thrombocytopenic Purpura, Congenital; Upshaw-Schulman Syndrome

Clinical and genetic characterization of classical forms of familial adenomatous polyposis: a Spanish population study.

PubMed

Rivera, B; González, S; Sánchez-Tomé, E; Blanco, I; Mercadillo, F; Letón, R; Benítez, J; Robledo, M; Capellá, G; Urioste, M

2011-04-01

Classical familial adenomatous polyposis (FAP) is characterized by the appearance of >100 colorectal adenomas. We screened the APC and MUTYH genes for mutations and evaluated the genotype-phenotype correlation in 136 Spanish classical FAP families. APC/MUTYH mutations were detected in 107 families. Sixty-four distinct APC point mutations were detected in 95 families of which all were truncating mutations. A significant proportion (39.6%) had not been previously reported. Mutations were spread over the entire coding region and great rearrangements were identified in six families. Another six families exhibited biallelic MUTYH mutations. No APC or MUTYH mutations were detected in 29 families. These APC/MUTYH-negative families showed clinical differences with the APC-positive families. A poor correlation between phenotype and mutation site was observed. Our results highlight that a broad approach in the genetic study must be considered for classical FAP due to involvement of both APC and MUTYH and the heterogeneous spectrum of APC mutations observed in this Spanish population. The scarcely consistent genotype-phenotype correlation does not allow making specific recommendations regarding screening and management. Differences observed in APC/MUTYH-negative families may reflect a genetic basis other than mutations in APC and MUTYH genes for FAP predisposition. © The Author 2010. Published by Oxford University Press on behalf of the European Society for Medical Oncology.

Using artificial neural networks to select upright cowpea (Vigna unguiculata) genotypes with high productivity and phenotypic stability.

PubMed

Barroso, L M A; Teodoro, P E; Nascimento, M; Torres, F E; Nascimento, A C C; Azevedo, C F; Teixeira, F R F

2016-11-03

Cowpea (Vigna unguiculata) is grown in three Brazilian regions: the Midwest, North, and Northeast, and is consumed by people on low incomes. It is important to investigate the genotype x environment (GE) interaction to provide accurate recommendations for farmers. The aim of this study was to identify cowpea genotypes with high adaptability and phenotypic stability for growing in the Brazilian Cerrado, and to compare the use of artificial neural networks with the Eberhart and Russell (1966) method. Six trials with upright cowpea genotypes were conducted in 2005 and 2006 in the States of Mato Grosso do Sul and Mato Grosso. The data were subjected to adaptability and stability analysis by the Eberhart and Russell (1966) method and artificial neural networks. The genotypes MNC99-537F-4 and EVX91-2E-2 provided grain yields above the overall environment means, and exhibited high stability according to both methods. Genotype IT93K-93-10 was the most suitable for unfavorable environments. There was a high correlation between the results of both methods in terms of classifying the genotypes by their adaptability and stability. Therefore, this new approach would be effective in quantifying the GE interaction in upright cowpea breeding programs.

Tumour risks and genotype-phenotype correlations associated with germline variants in succinate dehydrogenase subunit genes SDHB, SDHC and SDHD.

PubMed

Andrews, Katrina A; Ascher, David B; Pires, Douglas Eduardo Valente; Barnes, Daniel R; Vialard, Lindsey; Casey, Ruth T; Bradshaw, Nicola; Adlard, Julian; Aylwin, Simon; Brennan, Paul; Brewer, Carole; Cole, Trevor; Cook, Jackie A; Davidson, Rosemarie; Donaldson, Alan; Fryer, Alan; Greenhalgh, Lynn; Hodgson, Shirley V; Irving, Richard; Lalloo, Fiona; McConachie, Michelle; McConnell, Vivienne P M; Morrison, Patrick J; Murday, Victoria; Park, Soo-Mi; Simpson, Helen L; Snape, Katie; Stewart, Susan; Tomkins, Susan E; Wallis, Yvonne; Izatt, Louise; Goudie, David; Lindsay, Robert S; Perry, Colin G; Woodward, Emma R; Antoniou, Antonis C; Maher, Eamonn R

2018-06-01

Germline pathogenic variants in SDHB/SDHC / SDHD are the most frequent causes of inherited phaeochromocytomas/paragangliomas. Insufficient information regarding penetrance and phenotypic variability hinders optimum management of mutation carriers. We estimate penetrance for symptomatic tumours and elucidate genotype-phenotype correlations in a large cohort of SDHB/SDHC / SDHD mutation carriers. A retrospective survey of 1832 individuals referred for genetic testing due to a personal or family history of phaeochromocytoma/paraganglioma. 876 patients (401 previously reported) had a germline mutation in SDHB/SDHC / SDHD (n=673/43/160). Tumour risks were correlated with in silico structural prediction analyses. Tumour risks analysis provided novel penetrance estimates and genotype-phenotype correlations. In addition to tumour type susceptibility differences for individual genes, we confirmed that the SDHD: p.Pro81Leu mutation has a distinct phenotype and identified increased age-related tumour risks with highly destabilising SDHB missense mutations. By Kaplan-Meier analysis, the penetrance (cumulative risk of clinically apparent tumours) in SDHB and (paternally inherited) SDHD mutation-positive non-probands (n=371/67 with detailed clinical information) by age 60 years was 21.8% (95% CI 15.2% to 27.9%) and 43.2% (95% CI 25.4% to 56.7%), respectively. Risk of malignant disease at age 60 years in non-proband SDHB mutation carriers was 4.2%(95% CI 1.1% to 7.2%). With retrospective cohort analysis to adjust for ascertainment, cumulative tumour risks for SDHB mutation carriers at ages 60 years and 80 years were 23.9% (95% CI 20.9% to 27.4%) and 30.6% (95% CI 26.8% to 34.7%). Overall risks of clinically apparent tumours for SDHB mutation carriers are substantially lower than initially estimated and will improve counselling of affected families. Specific genotype-tumour risk associations provides a basis for novel investigative strategies into succinate dehydrogenase-related mechanisms of tumourigenesis and the development of personalised management for SDHB/SDHC / SDHD mutation carriers. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Predicted Mutation Strength of Nontruncating PKD1 Mutations Aids Genotype-Phenotype Correlations in Autosomal Dominant Polycystic Kidney Disease.

PubMed

Heyer, Christina M; Sundsbak, Jamie L; Abebe, Kaleab Z; Chapman, Arlene B; Torres, Vicente E; Grantham, Jared J; Bae, Kyongtae T; Schrier, Robert W; Perrone, Ronald D; Braun, William E; Steinman, Theodore I; Mrug, Michal; Yu, Alan S L; Brosnahan, Godela; Hopp, Katharina; Irazabal, Maria V; Bennett, William M; Flessner, Michael F; Moore, Charity G; Landsittel, Douglas; Harris, Peter C

2016-09-01

Autosomal dominant polycystic kidney disease (ADPKD) often results in ESRD but with a highly variable course. Mutations to PKD1 or PKD2 cause ADPKD; both loci have high levels of allelic heterogeneity. We evaluated genotype-phenotype correlations in 1119 patients (945 families) from the HALT Progression of PKD Study and the Consortium of Radiologic Imaging Study of PKD Study. The population was defined as: 77.7% PKD1, 14.7% PKD2, and 7.6% with no mutation detected (NMD). Phenotypic end points were sex, eGFR, height-adjusted total kidney volume (htTKV), and liver cyst volume. Analysis of the eGFR and htTKV measures showed that the PKD1 group had more severe disease than the PKD2 group, whereas the NMD group had a PKD2-like phenotype. In both the PKD1 and PKD2 populations, men had more severe renal disease, but women had larger liver cyst volumes. Compared with nontruncating PKD1 mutations, truncating PKD1 mutations associated with lower eGFR, but the mutation groups were not differentiated by htTKV. PKD1 nontruncating mutations were evaluated for conservation and chemical change and subdivided into strong (mutation strength group 2 [MSG2]) and weak (MSG3) mutation groups. Analysis of eGFR and htTKV measures showed that patients with MSG3 but not MSG2 mutations had significantly milder disease than patients with truncating cases (MSG1), an association especially evident in extreme decile populations. Overall, we have quantified the contribution of genic and PKD1 allelic effects and sex to the ADPKD phenotype. Intrafamilial correlation analysis showed that other factors shared by families influence htTKV, with these additional genetic/environmental factors significantly affecting the ADPKD phenotype. Copyright © 2016 by the American Society of Nephrology.

Butyrylcholinesterase (BChE) activity is associated with the risk of preeclampsia: influence on lipid and lipoprotein metabolism and oxidative stress.

PubMed

Rahimi, Zohreh; Ahmadi, Reza; Vaisi-Raygani, Asad; Rahimi, Ziba; Bahrehmand, Fariborz; Parsian, Abbas

2013-11-01

To determine the butyrylcholinesterase (BChE) activity and phenotypes in preeclampsia and its possible association with lipid and lipoprotein metabolism and oxidative stress in preeclamptic women. In a case-control study, 101 pregnant women with normal pregnancy and 198 women with preeclampsia from Western Iran were studied. The serum BChE activity and phenotypes were measured using spectrophotometric method. The apolipoprotein E (APOE) genotypes were identified using PCR-RFLP. The serum malondialdehyde (MDA) level and total antioxidant capacity (TAC) were determined by HPLC and commercial kits, respectively. The BChE activity and the frequency of non-usual BChE phenotype in preeclamptic women were significantly lower and higher, respectively compared to controls. There was a higher BChE activity in the presence of APOE ε3ε4 compared to ε3ε3 genotype in preeclamptic women. In addition, there were significant positive correlations between BChE activity and the levels of low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, total cholesterol (TC) and TAC. However, there was a negative but significant correlation between BChE activity and MDA level. Our study for the first time indicated that BChE activity might be involved in the pathogenesis of preeclampsia through influence on lipid and lipoprotein metabolism and oxidative stress.

Assessing the value of phenotypic information from non-genotyped animals for QTL mapping of complex traits in real and simulated populations.

PubMed

Melo, Thaise P; Takada, Luciana; Baldi, Fernando; Oliveira, Henrique N; Dias, Marina M; Neves, Haroldo H R; Schenkel, Flavio S; Albuquerque, Lucia G; Carvalheiro, Roberto

2016-06-21

QTL mapping through genome-wide association studies (GWAS) is challenging, especially in the case of low heritability complex traits and when few animals possess genotypic and phenotypic information. When most of the phenotypic information is from non-genotyped animals, GWAS can be performed using the weighted single-step GBLUP (WssGBLUP) method, which permits to combine all available information, even that of non-genotyped animals. However, it is not clear to what extent phenotypic information from non-genotyped animals increases the power of QTL detection, and whether factors such as the extent of linkage disequilibrium (LD) in the population and weighting SNPs in WssGBLUP affect the importance of using information from non-genotyped animals in GWAS. These questions were investigated in this study using real and simulated data. Analysis of real data showed that the use of phenotypes of non-genotyped animals affected SNP effect estimates and, consequently, QTL mapping. Despite some coincidence, the most important genomic regions identified by the analyses, either using or ignoring phenotypes of non-genotyped animals, were not the same. The simulation results indicated that the inclusion of all available phenotypic information, even that of non-genotyped animals, tends to improve QTL detection for low heritability complex traits. For populations with low levels of LD, this trend of improvement was less pronounced. Stronger shrinkage on SNPs explaining lower variance was not necessarily associated with better QTL mapping. The use of phenotypic information from non-genotyped animals in GWAS may improve the ability to detect QTL for low heritability complex traits, especially in populations in which the level of LD is high.

Revisiting Robustness and Evolvability: Evolution in Weighted Genotype Spaces

PubMed Central

Partha, Raghavendran; Raman, Karthik

2014-01-01

Robustness and evolvability are highly intertwined properties of biological systems. The relationship between these properties determines how biological systems are able to withstand mutations and show variation in response to them. Computational studies have explored the relationship between these two properties using neutral networks of RNA sequences (genotype) and their secondary structures (phenotype) as a model system. However, these studies have assumed every mutation to a sequence to be equally likely; the differences in the likelihood of the occurrence of various mutations, and the consequence of probabilistic nature of the mutations in such a system have previously been ignored. Associating probabilities to mutations essentially results in the weighting of genotype space. We here perform a comparative analysis of weighted and unweighted neutral networks of RNA sequences, and subsequently explore the relationship between robustness and evolvability. We show that assuming an equal likelihood for all mutations (as in an unweighted network), underestimates robustness and overestimates evolvability of a system. In spite of discarding this assumption, we observe that a negative correlation between sequence (genotype) robustness and sequence evolvability persists, and also that structure (phenotype) robustness promotes structure evolvability, as observed in earlier studies using unweighted networks. We also study the effects of base composition bias on robustness and evolvability. Particularly, we explore the association between robustness and evolvability in a sequence space that is AU-rich – sequences with an AU content of 80% or higher, compared to a normal (unbiased) sequence space. We find that evolvability of both sequences and structures in an AU-rich space is lesser compared to the normal space, and robustness higher. We also observe that AU-rich populations evolving on neutral networks of phenotypes, can access less phenotypic variation compared to normal populations evolving on neutral networks. PMID:25390641

Phenotypic Stability of Zea mays Grain Yield and Its Attributing Traits under Drought Stress

PubMed Central

Ali, Fawad; Ahsan, Muhammad; Ali, Qurban; Kanwal, Naila

2017-01-01

Phenotypic stability under stress environment facilitate the fitness of genotype and opens new horizons to explore the cryptic genetic variation. Variation in tolerance to drought stress, a major grain yield constraint to global maize production, was identified, at the phenotypic and genotypic level. Here we found a prominent hybrid H9 that showed fitness over four growing seasons for grain yield under water stress conditions. Genotypic and phenotypic correlation of yield attributing traits over four seasons demonstrated that cobs per plant, 100 seed weight, number of grains rows per cob, total dry matter, cob diameter had positive association (r2 = 0.3–0.9) to grain yield. The perturbation was found for chlorophyll content as it showed moderate to strong association (P < 0.01) over four seasons, might be due to environment or genotype dependent. Highest heritability (95%) and genetic advance (79%) for grain yield was found in H9 over four consecutive crop growing seasons. Combined analysis over four seasons showed that studied variables together explained 85% of total variation in dependent structure (grain yield) obtained by Principal component analysis. This significant finding is the best example of phenotypic stability of grain yield in H9 and made it best fitted for grain yield under drought stress scenario. Detailed genetic analysis of H9 will help us to identify significant loci and alleles that made H9 the best fitted and it could serve as a potential source to generate novel transgressive levels of tolerance for drought stress in arid/semiarid regions. PMID:28878785

Phenotypic Stability of Zea mays Grain Yield and Its Attributing Traits under Drought Stress.

PubMed

Ali, Fawad; Ahsan, Muhammad; Ali, Qurban; Kanwal, Naila

2017-01-01

Phenotypic stability under stress environment facilitate the fitness of genotype and opens new horizons to explore the cryptic genetic variation. Variation in tolerance to drought stress, a major grain yield constraint to global maize production, was identified, at the phenotypic and genotypic level. Here we found a prominent hybrid H 9 that showed fitness over four growing seasons for grain yield under water stress conditions. Genotypic and phenotypic correlation of yield attributing traits over four seasons demonstrated that cobs per plant, 100 seed weight, number of grains rows per cob, total dry matter, cob diameter had positive association ( r 2 = 0.3-0.9) to grain yield. The perturbation was found for chlorophyll content as it showed moderate to strong association ( P < 0.01) over four seasons, might be due to environment or genotype dependent. Highest heritability (95%) and genetic advance (79%) for grain yield was found in H 9 over four consecutive crop growing seasons. Combined analysis over four seasons showed that studied variables together explained 85% of total variation in dependent structure (grain yield) obtained by Principal component analysis. This significant finding is the best example of phenotypic stability of grain yield in H 9 and made it best fitted for grain yield under drought stress scenario. Detailed genetic analysis of H 9 will help us to identify significant loci and alleles that made H 9 the best fitted and it could serve as a potential source to generate novel transgressive levels of tolerance for drought stress in arid/semiarid regions.

Arylamine N-acetyltransferase (NAT2) mutations and their allelic linkage in unrelated caucasian individuals: Correlation with phenotypic activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cascorbi, I.; Drakoulis, N.; Brockmoeller, J.

1995-09-01

The polymorphic arylamine N-acetyltransferase (NAT2; EC2.3.1.5) is supposed to be a susceptibility factor for several drug side effects and certain malignancies. A group of 844 unrelated German subjects was genotyped for their acetylation type, and 563 of them were also phenotyped. Seven mutations of the NAT2 gene were evaluated by allele-specific PCR (mutation 341C to T) and PCR-RFLP for mutations at nt positions 191, 282, 481, 590, 803, and 857. From the mutation pattern eight different alleles, including the wild type coding for rapid acetylation and seven alleles coding for slow phenotype, were determined. Four hundred ninety-seven subjects had amore » genotype of slow acetylation (58.9%; 95% confidence limits 55.5%-62.2%). Phenotypic acetylation capacity was expressed as the ratio of 5-acetylamino-6-formylamino-3-methyluracil and 1-methylxanthine in urine after caffeine intake. Some 6.7% of the cases deviated in genotype and phenotype, but sequencing DNA of these probands revealed no new mutations. Furthermore, linkage pattern of the mutations was always confirmed, as tested in 533 subjects. In vivo acetylation capacity of homozygous wild-type subjects (NAT2{sup *}4/{sup *}4) was significantly higher than in heterozygous genotypes (P = .001). All mutant alleles showed low in vivo acetylation capacities, including the previously not-yet-defined alleles {sup *}5A, {sup *}5C, and {sup *}13. Moreover, distinct slow genotypes differed significantly among each other, as reflected in lower acetylation capacity of {sup *}6A, {sup *}7B, and {sup *}13 alleles than the group of {sup *}5 alleles. The study demonstrated differential phenotypic activity of various NAT2 genes and gives a solid basis for clinical and molecular-epidemiological investigations. 34 refs., 4 figs., 7 tabs.« less

Unravelling the pathogenic role and genotype-phenotype correlation of the USH2A p.(Cys759Phe) variant among Spanish families.

PubMed

Pérez-Carro, Raquel; Blanco-Kelly, Fiona; Galbis-Martínez, Lilián; García-García, Gema; Aller, Elena; García-Sandoval, Blanca; Mínguez, Pablo; Corton, Marta; Mahíllo-Fernández, Ignacio; Martín-Mérida, Inmaculada; Avila-Fernández, Almudena; Millán, José M; Ayuso, Carmen

2018-01-01

Mutations in USH2A cause both isolated Retinitis Pigmentosa (RP) and Usher syndrome (that implies RP and hearing impairment). One of the most frequent variants identified in this gene and among these patients is the p.(Cys759Phe) change. However, the pathogenic role of this allele has been questioned since it was found in homozygosity in two healthy siblings of a Spanish family. To assess the causative role of USH2A p.(Cys759Phe) in autosomal recessive RP (ARRP) and Usher syndrome type II (USH2) and to establish possible genotype-phenotype correlations associated with p.(Cys759Phe), we performed a comprehensive genetic and clinical study in patients suffering from any of the two above-mentioned diseases and carrying at least one p.(Cys759Phe) allele. Diagnosis was set according to previously reported protocols. Genetic analyses were performed by using classical molecular and Next-Generation Sequencing approaches. Probands of 57 unrelated families were molecularly studied and 63 patients belonging to these families were phenotypically evaluated. Molecular analysis characterized 100% of the cases, identifying: 11 homozygous patients for USH2A p.(Cys759Phe), 42 compound heterozygous patients (12 of them with another missense USH2A pathogenic variant and 30 with a truncating USH2A variant), and 4 patients carrying the p.(Cys759Phe) allele and a pathogenic variant in another RP gene (PROM1, CNGB1 or RP1). No additional causative variants were identified in symptomatic homozygous patients. Statistical analysis of clinical differences between zygosity states yielded differences (p≤0.05) in age at diagnosis of RP and hypoacusis, and progression of visual field loss. Homozygosity of p.(Cys759Phe) and compound heterozygosity with another USH2A missense variant is associated with ARRP or ARRP plus late onset hypoacusis (OR = 20.62, CI = 95%, p = 0.041). The present study supports the role of USH2A p.(Cys759Phe) in ARRP and USH2 pathogenesis, and demonstrates the clinical differences between different zygosity states. Phenotype-genotype correlations may guide the genetic characterization based upon specific clinical signs and may advise on the clinical management and prognosis based upon a specific genotype.

Genetic and phenotypic dissection of 1q43q44 microdeletion syndrome and neurodevelopmental phenotypes associated with mutations in ZBTB18 and HNRNPU.

PubMed

Depienne, Christel; Nava, Caroline; Keren, Boris; Heide, Solveig; Rastetter, Agnès; Passemard, Sandrine; Chantot-Bastaraud, Sandra; Moutard, Marie-Laure; Agrawal, Pankaj B; VanNoy, Grace; Stoler, Joan M; Amor, David J; Billette de Villemeur, Thierry; Doummar, Diane; Alby, Caroline; Cormier-Daire, Valérie; Garel, Catherine; Marzin, Pauline; Scheidecker, Sophie; de Saint-Martin, Anne; Hirsch, Edouard; Korff, Christian; Bottani, Armand; Faivre, Laurence; Verloes, Alain; Orzechowski, Christine; Burglen, Lydie; Leheup, Bruno; Roume, Joelle; Andrieux, Joris; Sheth, Frenny; Datar, Chaitanya; Parker, Michael J; Pasquier, Laurent; Odent, Sylvie; Naudion, Sophie; Delrue, Marie-Ange; Le Caignec, Cédric; Vincent, Marie; Isidor, Bertrand; Renaldo, Florence; Stewart, Fiona; Toutain, Annick; Koehler, Udo; Häckl, Birgit; von Stülpnagel, Celina; Kluger, Gerhard; Møller, Rikke S; Pal, Deb; Jonson, Tord; Soller, Maria; Verbeek, Nienke E; van Haelst, Mieke M; de Kovel, Carolien; Koeleman, Bobby; Monroe, Glen; van Haaften, Gijs; Attié-Bitach, Tania; Boutaud, Lucile; Héron, Delphine; Mignot, Cyril

2017-04-01

Subtelomeric 1q43q44 microdeletions cause a syndrome associating intellectual disability, microcephaly, seizures and anomalies of the corpus callosum. Despite several previous studies assessing genotype-phenotype correlations, the contribution of genes located in this region to the specific features of this syndrome remains uncertain. Among those, three genes, AKT3, HNRNPU and ZBTB18 are highly expressed in the brain and point mutations in these genes have been recently identified in children with neurodevelopmental phenotypes. In this study, we report the clinical and molecular data from 17 patients with 1q43q44 microdeletions, four with ZBTB18 mutations and seven with HNRNPU mutations, and review additional data from 37 previously published patients with 1q43q44 microdeletions. We compare clinical data of patients with 1q43q44 microdeletions with those of patients with point mutations in HNRNPU and ZBTB18 to assess the contribution of each gene as well as the possibility of epistasis between genes. Our study demonstrates that AKT3 haploinsufficiency is the main driver for microcephaly, whereas HNRNPU alteration mostly drives epilepsy and determines the degree of intellectual disability. ZBTB18 deletions or mutations are associated with variable corpus callosum anomalies with an incomplete penetrance. ZBTB18 may also contribute to microcephaly and HNRNPU to thin corpus callosum, but with a lower penetrance. Co-deletion of contiguous genes has additive effects. Our results confirm and refine the complex genotype-phenotype correlations existing in the 1qter microdeletion syndrome and define more precisely the neurodevelopmental phenotypes associated with genetic alterations of AKT3, ZBTB18 and HNRNPU in humans.

Role of GnRH receptor mutations in patients with a wide spectrum of pubertal delay

PubMed Central

Beneduzzi, Daiane; Trarbach, Ericka B.; Min, Le; Jorge, Alexander A. L.; Garmes, Heraldo M.; Renk, Alessandra Covallero; Fichna, Marta; Fichna, Piotr; Arantes, Karina A.; Costa, Elaine M. F.; Zhang, Anna; Adeola, Oluwaseun; Wen, Junping; Carroll, Rona S.; Mendonça, Berenice B.; Kaiser, Ursula B.; Latronico, Ana Claudia; Silveira, Letícia F. G.

2014-01-01

Objective To analyze the GNRHR in patients with normosmic isolated hypogonadotropic hypogonadism (IHH) and constitutional delay of growth and puberty (CDGP). Design Molecular analysis and in vitro experiments correlated with phenotype. Setting Academic medical center. Patient(s) 110 individuals with normosmic IHH (74 males) and 50 with CGDP. Intervention(s) GNRHR coding region was amplified and sequenced. Main Outcome Measure(s) Novel variants were submitted to in vitro analysis. Frequency of mutations and genotype-phenotype correlation were analyzed. Microsatellite markers flanking GNRHR were examined in patients carrying the same mutation to investigate a possible founder effect. Result(s) Eleven IHH patients (10%) carried biallelic GNRHR mutations. In vitro analysis of novel variants (p.Y283H and p.V134G) demonstrated complete inactivation. The founder effect study revealed that Brazilian patients carrying the p.R139H mutation shared the same haplotype. Phenotypic spectrum in patients with GNRHR mutations varied from complete GnRH deficiency to partial and reversible IHH, with a relatively good genotype-phenotype correlation. One boy with CDGP was heterozygous for the p.Q106R variant, which was not considered pathogenic. Conclusion(s) GNRHR mutations are a frequent cause of congenital normosmic IHH and should be the first candidate gene for genetic screening in this condition, especially in autosomal recessive familial cases. The founder effect study suggested that the p.R139H mutation arises from a common ancestor in the Brazilian population. Finally, mutations in GNRHR do not appear to be involved in the pathogenesis of CDGP. PMID:25016926

Genotypic Complexity of Fisher’s Geometric Model

PubMed Central

Hwang, Sungmin; Park, Su-Chan; Krug, Joachim

2017-01-01

Fisher’s geometric model was originally introduced to argue that complex adaptations must occur in small steps because of pleiotropic constraints. When supplemented with the assumption of additivity of mutational effects on phenotypic traits, it provides a simple mechanism for the emergence of genotypic epistasis from the nonlinear mapping of phenotypes to fitness. Of particular interest is the occurrence of reciprocal sign epistasis, which is a necessary condition for multipeaked genotypic fitness landscapes. Here we compute the probability that a pair of randomly chosen mutations interacts sign epistatically, which is found to decrease with increasing phenotypic dimension n, and varies nonmonotonically with the distance from the phenotypic optimum. We then derive expressions for the mean number of fitness maxima in genotypic landscapes comprised of all combinations of L random mutations. This number increases exponentially with L, and the corresponding growth rate is used as a measure of the complexity of the landscape. The dependence of the complexity on the model parameters is found to be surprisingly rich, and three distinct phases characterized by different landscape structures are identified. Our analysis shows that the phenotypic dimension, which is often referred to as phenotypic complexity, does not generally correlate with the complexity of fitness landscapes and that even organisms with a single phenotypic trait can have complex landscapes. Our results further inform the interpretation of experiments where the parameters of Fisher’s model have been inferred from data, and help to elucidate which features of empirical fitness landscapes can be described by this model. PMID:28450460

The Population Structure and Diversity of Eggplant from Asia and the Mediterranean Basin

PubMed Central

Cericola, Fabio; Portis, Ezio; Toppino, Laura; Barchi, Lorenzo; Acciarri, Nazareno; Ciriaci, Tommaso; Sala, Tea; Rotino, Giuseppe Leonardo; Lanteri, Sergio

2013-01-01

A collection of 238 eggplant breeding lines, heritage varieties and selections within local landraces provenanced from Asia and the Mediterranean Basin was phenotyped with respect to key plant and fruit traits, and genotyped using 24 microsatellite loci distributed uniformly throughout the genome. STRUCTURE analysis based on the genotypic data identified two major sub-groups, which to a large extent mirrored the provenance of the entries. With the goal to identify true-breeding types, 38 of the entries were discarded on the basis of microsatellite-based residual heterozygosity, along with a further nine which were not phenotypically uniform. The remaining 191 entries were scored for a set of 19 fruit and plant traits in a replicated experimental field trial. The phenotypic data were subjected to principal component and hierarchical principal component analyses, allowing three major morphological groups to be identified. All three morphological groups were represented in both the “Occidental” and the “Oriental” germplasm, so the correlation between the phenotypic and the genotypic data sets was quite weak. The relevance of these results for evolutionary studies and the further improvement of eggplant are discussed. The population structure of the core set of germplasm shows that it can be used as a basis for an association mapping approach. PMID:24040032

The population structure and diversity of eggplant from Asia and the Mediterranean Basin.

PubMed

Cericola, Fabio; Portis, Ezio; Toppino, Laura; Barchi, Lorenzo; Acciarri, Nazareno; Ciriaci, Tommaso; Sala, Tea; Rotino, Giuseppe Leonardo; Lanteri, Sergio

2013-01-01

A collection of 238 eggplant breeding lines, heritage varieties and selections within local landraces provenanced from Asia and the Mediterranean Basin was phenotyped with respect to key plant and fruit traits, and genotyped using 24 microsatellite loci distributed uniformly throughout the genome. STRUCTURE analysis based on the genotypic data identified two major sub-groups, which to a large extent mirrored the provenance of the entries. With the goal to identify true-breeding types, 38 of the entries were discarded on the basis of microsatellite-based residual heterozygosity, along with a further nine which were not phenotypically uniform. The remaining 191 entries were scored for a set of 19 fruit and plant traits in a replicated experimental field trial. The phenotypic data were subjected to principal component and hierarchical principal component analyses, allowing three major morphological groups to be identified. All three morphological groups were represented in both the "Occidental" and the "Oriental" germplasm, so the correlation between the phenotypic and the genotypic data sets was quite weak. The relevance of these results for evolutionary studies and the further improvement of eggplant are discussed. The population structure of the core set of germplasm shows that it can be used as a basis for an association mapping approach.

Genotype-Phenotype Correlation in NF1: Evidence for a More Severe Phenotype Associated with Missense Mutations Affecting NF1 Codons 844-848.

PubMed

Koczkowska, Magdalena; Chen, Yunjia; Callens, Tom; Gomes, Alicia; Sharp, Angela; Johnson, Sherrell; Hsiao, Meng-Chang; Chen, Zhenbin; Balasubramanian, Meena; Barnett, Christopher P; Becker, Troy A; Ben-Shachar, Shay; Bertola, Debora R; Blakeley, Jaishri O; Burkitt-Wright, Emma M M; Callaway, Alison; Crenshaw, Melissa; Cunha, Karin S; Cunningham, Mitch; D'Agostino, Maria D; Dahan, Karin; De Luca, Alessandro; Destrée, Anne; Dhamija, Radhika; Eoli, Marica; Evans, D Gareth R; Galvin-Parton, Patricia; George-Abraham, Jaya K; Gripp, Karen W; Guevara-Campos, Jose; Hanchard, Neil A; Hernández-Chico, Concepcion; Immken, LaDonna; Janssens, Sandra; Jones, Kristi J; Keena, Beth A; Kochhar, Aaina; Liebelt, Jan; Martir-Negron, Arelis; Mahoney, Maurice J; Maystadt, Isabelle; McDougall, Carey; McEntagart, Meriel; Mendelsohn, Nancy; Miller, David T; Mortier, Geert; Morton, Jenny; Pappas, John; Plotkin, Scott R; Pond, Dinel; Rosenbaum, Kenneth; Rubin, Karol; Russell, Laura; Rutledge, Lane S; Saletti, Veronica; Schonberg, Rhonda; Schreiber, Allison; Seidel, Meredith; Siqveland, Elizabeth; Stockton, David W; Trevisson, Eva; Ullrich, Nicole J; Upadhyaya, Meena; van Minkelen, Rick; Verhelst, Helene; Wallace, Margaret R; Yap, Yoon-Sim; Zackai, Elaine; Zonana, Jonathan; Zurcher, Vickie; Claes, Kathleen; Martin, Yolanda; Korf, Bruce R; Legius, Eric; Messiaen, Ludwine M

2018-01-04

Neurofibromatosis type 1 (NF1), a common genetic disorder with a birth incidence of 1:2,000-3,000, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and a single amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 individuals (129 unrelated probands and 33 affected relatives) heterozygous for a constitutional missense mutation affecting one of five neighboring NF1 codons-Leu844, Cys845, Ala846, Leu847, and Gly848-located in the cysteine-serine-rich domain (CSRD). Collectively, these recurrent missense mutations affect ∼0.8% of unrelated NF1 mutation-positive probands in the University of Alabama at Birmingham (UAB) cohort. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent in these individuals compared with classic NF1-affected cohorts (both p < 0.0001). Nearly half of the individuals had symptomatic or asymptomatic optic pathway gliomas and/or skeletal abnormalities. Additionally, variants in this region seem to confer a high predisposition to develop malignancies compared with the general NF1-affected population (p = 0.0061). Our results demonstrate that these NF1 missense mutations, although located outside the GAP-related domain, may be an important risk factor for a severe presentation. A genotype-phenotype correlation at the NF1 region 844-848 exists and will be valuable in the management and genetic counseling of a significant number of individuals. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

A quadratically regularized functional canonical correlation analysis for identifying the global structure of pleiotropy with NGS data

PubMed Central

Zhu, Yun; Fan, Ruzong; Xiong, Momiao

2017-01-01

Investigating the pleiotropic effects of genetic variants can increase statistical power, provide important information to achieve deep understanding of the complex genetic structures of disease, and offer powerful tools for designing effective treatments with fewer side effects. However, the current multiple phenotype association analysis paradigm lacks breadth (number of phenotypes and genetic variants jointly analyzed at the same time) and depth (hierarchical structure of phenotype and genotypes). A key issue for high dimensional pleiotropic analysis is to effectively extract informative internal representation and features from high dimensional genotype and phenotype data. To explore correlation information of genetic variants, effectively reduce data dimensions, and overcome critical barriers in advancing the development of novel statistical methods and computational algorithms for genetic pleiotropic analysis, we proposed a new statistic method referred to as a quadratically regularized functional CCA (QRFCCA) for association analysis which combines three approaches: (1) quadratically regularized matrix factorization, (2) functional data analysis and (3) canonical correlation analysis (CCA). Large-scale simulations show that the QRFCCA has a much higher power than that of the ten competing statistics while retaining the appropriate type 1 errors. To further evaluate performance, the QRFCCA and ten other statistics are applied to the whole genome sequencing dataset from the TwinsUK study. We identify a total of 79 genes with rare variants and 67 genes with common variants significantly associated with the 46 traits using QRFCCA. The results show that the QRFCCA substantially outperforms the ten other statistics. PMID:29040274

Spectral reflectance indices as a selection criterion for yield improvement in wheat

NASA Astrophysics Data System (ADS)

Babar, Md. Ali

2005-11-01

Scope and methods of study. Yield in wheat ( Triticum aestivum L.) is a complex trait and influenced by many environmental factors, and yield improvement is a daunting task for wheat breeders. Spectral reflectance indices (SRIs) have been used to study different physiological traits in wheat. SRIs have the potential to differentiate genotypes for grain yield. SRIs strongly associated with grain yield can be used to achieve effective genetic gain in wheat under different environments. Three experiments (15 adapted genotypes, 25 and 36 random sister lines derived from two different crosses) under irrigated conditions, and three experiments (each with 30 advanced genotypes) under water-limited conditions were conducted in three successive years in Northwest Mexico at the CIMMYT (International Maize and wheat Improvement Center) experimental station. SRIs and different agronomic data were collected for three years, and biomass was harvested for two years. Phenotypic and genetic correlations between SRIs and grain yield, between SRIs and biomass, realized and broad sense heritability, direct and correlated selection responses for grain yield, and SRIs were calculated. Findings and conclusion. Seven SRIs were calculated, and three near infrared based indices (WI, NWI-1 and NWI-2) showed higher level of genetic and phenotypic correlations with grain yield, yield components and biomass than other SRIs (PRI, RNDVI, GNDVI, and SR) under both irrigated and water limiting environments. Moderate to high realized and broad sense heritability, and selection response were demonstrated by the three NIR based indices. High efficiency of correlated response for yield estimation was demonstrated by the three NIR based indices. The ratio between the correlated response to grain yield based on the three NIR based indices and direct selection response for grain yield was very close to one. The NIR based indices showed very high accuracy in selecting superior genotypes for grain yield under both well-watered and water-limited conditions. These results demonstrated that effective genetic gain in grain yield improvement can be achieved by making selections with the three NIR based indices.

Alternating Hemiplegia of Childhood: Retrospective Genetic Study and Genotype-Phenotype Correlations in 187 Subjects from the US AHCF Registry

PubMed Central

Viollet, Louis; Glusman, Gustavo; Murphy, Kelley J.; Newcomb, Tara M.; Reyna, Sandra P.; Sweney, Matthew; Nelson, Benjamin; Andermann, Frederick; Andermann, Eva; Acsadi, Gyula; Barbano, Richard L.; Brown, Candida; Brunkow, Mary E.; Chugani, Harry T.; Cheyette, Sarah R.; Collins, Abigail; DeBrosse, Suzanne D.; Galas, David; Friedman, Jennifer; Hood, Lee; Huff, Chad; Jorde, Lynn B.; King, Mary D.; LaSalle, Bernie; Leventer, Richard J.; Lewelt, Aga J.; Massart, Mylynda B.; Mérida, Mario R.; Ptáček, Louis J.; Roach, Jared C.; Rust, Robert S.; Renault, Francis; Sanger, Terry D.; Sotero de Menezes, Marcio A.; Tennyson, Rachel; Uldall, Peter; Zhang, Yue; Zupanc, Mary; Xin, Winnie; Silver, Kenneth; Swoboda, Kathryn J.

2015-01-01

Mutations in ATP1A3 cause Alternating Hemiplegia of Childhood (AHC) by disrupting function of the neuronal Na+/K+ ATPase. Published studies to date indicate 2 recurrent mutations, D801N and E815K, and a more severe phenotype in the E815K cohort. We performed mutation analysis and retrospective genotype-phenotype correlations in all eligible patients with AHC enrolled in the US AHC Foundation registry from 1997-2012. Clinical data were abstracted from standardized caregivers’ questionnaires and medical records and confirmed by expert clinicians. We identified ATP1A3 mutations by Sanger and whole genome sequencing, and compared phenotypes within and between 4 groups of subjects, those with D801N, E815K, other ATP1A3 or no ATP1A3 mutations. We identified heterozygous ATP1A3 mutations in 154 of 187 (82%) AHC patients. Of 34 unique mutations, 31 (91%) are missense, and 16 (47%) had not been previously reported. Concordant with prior studies, more than 2/3 of all mutations are clustered in exons 17 and 18. Of 143 simplex occurrences, 58 had D801N (40%), 38 had E815K (26%) and 11 had G937R (8%) mutations. Patients with an E815K mutation demonstrate an earlier age of onset, more severe motor impairment and a higher prevalence of status epilepticus. This study further expands the number and spectrum of ATP1A3 mutations associated with AHC and confirms a more deleterious effect of the E815K mutation on selected neurologic outcomes. However, the complexity of the disorder and the extensive phenotypic variability among subgroups merits caution and emphasizes the need for further studies. PMID:25996915

Hypertension is a characteristic complication of X-linked hypophosphatemia.

PubMed

Nakamura, Yoshie; Takagi, Masaki; Takeda, Ryojun; Miyai, Kentaro; Hasegawa, Yukihiro

2017-03-31

X-linked hypophosphatemia (XLH) is a group of rare disorders caused by defective proximal tubular reabsorption of phosphate. Mutations in the PHEX gene are responsible for the majority of cases. There are very few reports of long-term complications of XLH other than skeletal and dental diseases. The aim of this study was to identify the phenotypic presentation of XLH during adulthood including complications other than skeletal and dental diseases. The clinical and biochemical phenotype of 22 adult patients with a PHEX gene mutation were examined retrospectively from their medical records. 6 patients had hypertension. The average age of hypertension onset was 29.0 years. Secondary hyperparathyroidism preceded the development of hypertension in 5 patients. 1 patient developed tertiary hyperparathyroidism. 15 patients had nephrocalcinosis. 2 patients had chronic renal dysfunction. Patients with hypertension had a significantly lower eGFR (p=0.010) compared to patients without hypertension. No significant difference was found in any other parameters. To examine the genotype-phenotype correlation, 10 adult males were chosen for analysis. No significant genotype-phenotype correlation analysis was revealed in any of the complications. However, there was a possibility that the age at nephrocalcinosis onset was younger in the non-missense mutation group than in the missense mutation group (p=0.063). This study corroborated the view that early-onset hypertension could be one of the characteristic complications seen in XLH patients. Considering the limited number of our patients, further study is necessary to address a potential cause of hypertension. XLH patients require careful lifelong treatment.

Genotypic and phenotypic diversity of Alicyclobacillus acidocaldarius isolates.

PubMed

Félix-Valenzuela, L; Guardiola-Avila, I; Burgara-Estrella, A; Ibarra-Zavala, M; Mata-Haro, V

2015-10-01

The fruit juice industry recognizes Alicyclobacillus as a major quality control target micro-organism. In this study, we analysed 19 bacterial isolates to identify Alicyclobacillus species by polymerase chain reaction (PCR) and sequencing analyses. Phenotypic and genomic diversity among isolates were investigated by API 50CHB system and ERIC-PCR (enterobacterial repetitive intergenic consensus-PCR) respectively. All bacterial isolates were identified as Alicyclobacillus acidocaldarius, and almost all showed identical DNA sequences according to their 16S rRNA (rDNA) gene partial sequences. Only few carbohydrates were fermented by A. acidocaldarius isolates, and there was little variability in the biochemical profile. Genotypic fingerprinting of the A. acidocaldarius isolates showed high diversity, and clusters by ERIC-PCR were distinct to those obtained from the 16S rRNA gene phylogenetic tree. There was no correlation between phenotypic and genotypic variability in the A. acidocaldarius isolates analysed in this study. Detection of Alicyclobacillus strains is imperative in fruit concentrates and juices due to the production of guaiacol. Identification of the genera originates rejection of the product by processing industry. However, not all the Alicyclobacillus species are deteriorative and hence the importance to differentiate among them. In this study, partial 16S ribosomal RNA sequence alignment allowed the differentiation of species. In addition, ERIC-PCR was introduced for the genotypic characterization of Alicyclobacillus, as an alternative for differentiation among isolates from the same species. © 2015 The Society for Applied Microbiology.

The natural history of SCO2 deficiency in 36 Polish children confirmed the genotype-phenotype correlation.

PubMed

Pronicka, Ewa; Piekutowska-Abramczuk, Dorota; Szymańska-Dębińska, Tamara; Bielecka, Liliana; Kowalski, Paweł; Luczak, Sylwia; Karkucińska-Więckowska, Agnieszka; Migdał, Marek; Kubalska, Jolanta; Zimowski, Janusz; Jamroz, Ewa; Wierzba, Jolanta; Sykut-Cegielska, Jolanta; Pronicki, Maciej; Zaremba, Jacek; Krajewska-Walasek, Małgorzata

2013-11-01

The aim of this study was to assess the natural history of the SCO2 deficiency in relation to the genotype in a cohort of 62 patients with SCO2 mutations (36 this study, 26 previous reports). A novel, milder phenotype (disease onset delayed until one year after birth, nonspecific encephalomyopathy, and 2-4 year survival period) associated with compound heterozygosity of the common p.E140K and a novel p.M177T mutations extends the range of symptoms of the SCO2 deficiency. The prevalence of SCO2 deficiency in Poland is relatively high. A search for SCO2 mutations in patients with histology resembling SMA appears to efficiently improve the detection rate. Copyright © 2013 Elsevier B.V. and Mitochondria Research Society. All rights reserved. All rights reserved.

P17.04 Radiomics analysis of primary central nervous system lymphoma (PCNSL) - A LOC network study

PubMed Central

Royer-Perron, L.; Bruno, A.; Daniau, M.; Labrèche, K.; Mokhtari, K.; Nguyen Them, L.; Houillier, C.; Soussain, C.; Hoang-Xuan, K.; Alentorn, A.

2016-01-01

Abstract Background: PCNSL are rare extranodal, malignant non-Hodgkin lymphomas of diffuse large B-cell type confined to the CNS. In the last years, several recurrent molecular genetic alterations have been described in PCNSL but whether they are correlated with the tumor anatomical localization has never been investigated. Objectives: We sought to analyze a genotype (molecular alterations) - phenotype (MRI data) in PCNSL. Material and methods: 50 PCNSL MR images of treatment-naïve patients were correlated with molecular alterations (i.e. MYD88 L265P, CD79B and TERT promoter mutations as well as a novel chimeric transcript that our laboratory has recently identified in PCNSL) obtained by Sanger sequencing. MRI data was analyzed as follows: (i) NIfTI data were registered to a 1.0 mm isotropic, high-resolution T1-weighted brain atlas provided by the Montreal Neurological Institute (MNI152) using a mutual information algorithm with a 12-degree of freedom transformation with FSL-FLIRT; (ii) gadolinium-enhancing lesions were manually segmented and saved as voxels-of-interest (VOIs); (iii) A heat-map for the frequency of lesion occurrence was reconstructed and superimposed on the reference MNI152; (iv) Structure probability maps (brain regions) were defined according to Talairach MRI Atlas and (v) genotype - phenotype correlation was performed using voxel-based lesion-symptom mapping (VLSM) using FDR < 0.05 after 4000 permutations. Results: We found mutations of MYD88 in 18 patients, of CD79B in 15 patients and of TERT promoter in 6 patients. The novel chimeric transcript was identified in 11 patients. PCNSL harboring TERT promoter mutations and the chimeric transcript were more frequently found in the corpus callosum (FDR < 0.05). Conversely, we did not find a specific genotype-phenotype correlation with the rest of molecular alterations. Conclusion: We provide a MRI probabilistic atlas linking genotype to phenotype in PCNSL. These results need further investigation. Acknowledgements: Association pour la Recherche sur les Tumeurs Cérébrales (ARTC), Ligue contre le Cancer, Fondation pour la recherche médicale, Institut National du Cancer (INCa), Cancéropôle Île-de-France, Département de la Recherche Clinique de l’APHP, CRC de l’APHP, réseau Lymphomes Oculo-Cérébraux (LOC).

Elevated lung cancer risk is associated with deficiencies in cell cycle checkpoints: Genotype and phenotype analyses from a case-control study

PubMed Central

Zheng, Yun-Ling; Kosti, Ourania; Loffredo, Christopher; Bowman, Elise; Mechanic, Leah; Perlmutter, Donna; Jones, Raymond; Shields, Peter G.; Harris, Curtis

2010-01-01

Cell cycle checkpoints play critical roles in the maintenance of genomic integrity and inactivation of checkpoint genes, and are frequently perturbed in most cancers. In a case-control study of 299 non-small cell lung cancer cases and 550 controls in Maryland, we investigated the association between γ-radiation-induced G2/M arrest in cultured blood lymphocytes and lung cancer risk, and examined genotype-phenotype correlations between genetic polymorphisms of 20 genes involving in DNA repair and cell cycle control and γ-radiation-induced G2/M arrest. The study was specifically designed to examine race and gender differences in risk factors. Our data indicated that a less efficient DNA damage-induced G2/M checkpoint was associated with an increased risk of lung cancer in African American women with an adjusted odds ratio (OR) of 2.63 (95% CI = 1.01 – 7.26); there were no statistically significant associations for Caucasians, or African American men. When the African American women were categorized into quartiles, a significant reverse trend of decreased G2/M checkpoint function and increased lung cancer risk was present, with lowest-vs-highest quartile OR of 13.72 (95% CI = 2.30 – 81.92, Ptrend < 0.01). Genotype-phenotype correlation analysis indicated that polymorphisms in ATM, CDC25C, CDKN1A, BRCA2, ERCC6, TP53, and TP53BP1 genes were significantly associated with the γ-radiation-induced G2/M arrest phenotype. This study provides evidence that a less efficient G2/M checkpoint is significantly associated with lung cancer risk in African American women. The data also suggested that the function of G2/M checkpoint is modulated by genetic polymorphisms in genes involved in DNA repair and cell cycle control. PMID:19626602

Neurogenetic disorders in the Basque population.

PubMed

Martí Massó, José Félix; Zarranz, Juan José; Otaegui, David; López de Munain, Adolfo

2015-01-01

In the molecular era, the study of neurogenetic disorders in relict populations provides an opportunity to discover new genes by linkage studies and to establish clearer genotype-phenotype correlations in large cohorts of individuals carrying the same mutation. The Basque people are one of the most ancient populations living in Europe and represent an excellent resource for this type of analysis in certain genetic conditions. Our objective was to describe neurogenetic disorders reported in the Basque population due to the presence of ancestral mutations or an accumulation of cases or both. We conducted a search in PubMed with the terms: Basque, neurogenetic disorders, genetic risk, and neurological disorders. We identified nine autosomal and two recessive disorders in the Basque population attributable to ancestral mutations (such as in PNRP, PARK8, FTDP-TDP43, LGMD2A, VCP, c9ORF72, and CMT4A), highly prevalent (DM1) or involving unique mutations (PARK1 or MAPT). Other genes were reported for their role as protective/risk factors in complex diseases such as multiple sclerosis, Alzheimer's disease, and Parkinson's disease. At the present time, when powerful sequencing techniques are identifying large numbers of genetic variants associated with unique phenotypes, the scrutiny of these findings in genetically homogeneous populations can help analyze genotype-phenotype correlations. © 2014 John Wiley & Sons Ltd/University College London.

Combining Genotype, Phenotype, and Environment to Infer Potential Candidate Genes.

PubMed

Talbot, Benoit; Chen, Ting-Wen; Zimmerman, Shawna; Joost, Stéphane; Eckert, Andrew J; Crow, Taylor M; Semizer-Cuming, Devrim; Seshadri, Chitra; Manel, Stéphanie

2017-03-01

Population genomic analysis can be an important tool in understanding local adaptation. Identification of potential adaptive loci in such analyses is usually based on the survey of a large genomic dataset in combination with environmental variables. Phenotypic data are less commonly incorporated into such studies, although combining a genome scan analysis with a phenotypic trait analysis can greatly improve the insights obtained from each analysis individually. Here, we aimed to identify loci potentially involved in adaptation to climate in 283 Loblolly pine (Pinus taeda) samples from throughout the species' range in the southeastern United States. We analyzed associations between phenotypic, molecular, and environmental variables from datasets of 3082 single nucleotide polymorphism (SNP) loci and 3 categories of phenotypic traits (gene expression, metabolites, and whole-plant traits). We found only 6 SNP loci that displayed potential signals of local adaptation. Five of the 6 identified SNPs are linked to gene expression traits for lignin development, and 1 is linked with whole-plant traits. We subsequently compared the 6 candidate genes with environmental variables and found a high correlation in only 3 of them (R2 > 0.2). Our study highlights the need for a combination of genotypes, phenotypes, and environmental variables, and for an appropriate sampling scheme and study design, to improve confidence in the identification of potential candidate genes. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Phenotype and genotype in 17 patients with Goltz-Gorlin syndrome.

PubMed

Maas, S M; Lombardi, M P; van Essen, A J; Wakeling, E L; Castle, B; Temple, I K; Kumar, V K A; Writzl, K; Hennekam, Raoul C M

2009-10-01

Goltz-Gorlin syndrome or focal dermal hypoplasia is a highly variable, X-linked dominant syndrome with abnormalities of ectodermal and mesodermal origin. In 2007, mutations in the PORCN gene were found to be causative in Goltz-Gorlin syndrome. A series of 17 patients with Goltz-Gorlin syndrome is reported on, and their phenotype and genotype are described. In 14 patients (13 females and one male), a PORCN mutation was found. Mutations included nonsense (n = 5), frameshift (n = 2), aberrant splicing (n = 2) and missense (n = 5) mutations. No genotype-phenotype correlation was found. All patients with the classical features of the syndrome had a detectable mutation. In three females with atypical signs, no mutation was found. The male patient had classical features and showed mosaicism for a PORCN nonsense mutation in fibroblasts. Two affected sisters had a mutation not detectable in their parents, supporting germline mosaicism. Their father had undergone radiation for testicular cancer in the past. Two classically affected females had three severely affected female fetuses which all had midline thoracic and abdominal wall defects, resembling the pentalogy of Cantrell and the limb-body wall complex. Thoracic and abdominal wall defects were also present in two surviving patients. PORCN mutations can possibly cause pentalogy of Cantrell and limb-body wall complexes as well. Therefore, particularly in cases with limb defects, it seems useful to search for these. PORCN mutations can be found in all classically affected cases of Goltz-Gorlin syndrome, including males. Somatic and germline mosaicism occur. There is no evident genotype-phenotype correlation.

Fabry disease in children: correlation between ocular manifestations, genotype and systemic clinical severity.

PubMed

Allen, L E; Cosgrave, E M; Kersey, J P; Ramaswami, U

2010-12-01

Fabry disease is an X linked lysosomal disorder associated with severe multiorgan failure and premature death. This study aims to determine the prevalence of ophthalmic manifestations in children with the condition and investigate the correlation with genotype and systemic disease severity. The records of 26 children from 18 pedigrees with Fabry disease undergoing regular ophthalmic and systemic examination were reviewed. All pedigrees underwent GLA gene sequencing to determine genotype. Correlations between ocular and systemic phenotype and genotype were investigated. Corneal verticillata occurred in 50% of the children in this study (95% CI, 29% to 79%). Children with ophthalmic manifestations were more likely to have loss-of-function GLA mutations (p=0.003). Retinal vascular tortuosity was seen in seven children (27%), all of whom had systemic symptoms suggestive of autonomic neuropathy, such as diarrhoea and syncope. These symptoms seemed less prevalent in children without retinal vascular changes, although this did not reach statistical significance (p=0.134). Ophthalmic manifestations of Fabry disease are common even in young children with loss-of-function GLA gene mutations. Although the limited sample size possibly prevented statistical significance, systemic symptoms of autonomic neuropathy often coexist with retinal vascular changes and may share the same pathogenesis.

Leukotriene A4 Hydrolase Genotype and HIV Infection Influence Intracerebral Inflammation and Survival From Tuberculous Meningitis.

PubMed

Thuong, Nguyen T T; Heemskerk, Dorothee; Tram, Trinh T B; Thao, Le T P; Ramakrishnan, Lalita; Ha, Vu T N; Bang, Nguyen D; Chau, Tran T H; Lan, Nguyen H; Caws, Maxine; Dunstan, Sarah J; Chau, Nguyen V V; Wolbers, Marcel; Mai, Nguyen T H; Thwaites, Guy E

2017-04-01

Tuberculous meningitis (TBM) is the most devastating form of tuberculosis, yet very little is known about the pathophysiology. We hypothesized that the genotype of leukotriene A4 hydrolase (encoded by LTA4H), which determines inflammatory eicosanoid expression, influences intracerebral inflammation, and predicts survival from TBM. We characterized the pretreatment clinical and intracerebral inflammatory phenotype and 9-month survival of 764 adults with TBM. All were genotyped for single-nucleotide polymorphism rs17525495, and inflammatory phenotype was defined by cerebrospinal fluid (CSF) leukocyte and cytokine concentrations. LTA4H genotype predicted survival of human immunodeficiency virus (HIV)-uninfected patients, with TT-genotype patients significantly more likely to survive TBM than CC-genotype patients, according to Cox regression analysis (univariate P = .040 and multivariable P = .037). HIV-uninfected, TT-genotype patients had high CSF proinflammatory cytokine concentrations, with intermediate and lower concentrations in those with CT and CC genotypes. Increased CSF cytokine concentrations correlated with more-severe disease, but patients with low CSF leukocytes and cytokine concentrations were more likely to die from TBM. HIV infection independently predicted death due to TBM (hazard ratio, 3.94; 95% confidence interval, 2.79-5.56) and was associated with globally increased CSF cytokine concentrations, independent of LTA4H genotype. LTA4H genotype and HIV infection influence pretreatment inflammatory phenotype and survival from TBM. LTA4H genotype may predict adjunctive corticosteroid responsiveness in HIV-uninfected individuals. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Exhaustive Analysis of a Genotype Space Comprising 1015 Central Carbon Metabolisms Reveals an Organization Conducive to Metabolic Innovation

PubMed Central

Hosseini, Sayed-Rzgar; Barve, Aditya; Wagner, Andreas

2015-01-01

All biological evolution takes place in a space of possible genotypes and their phenotypes. The structure of this space defines the evolutionary potential and limitations of an evolving system. Metabolism is one of the most ancient and fundamental evolving systems, sustaining life by extracting energy from extracellular nutrients. Here we study metabolism’s potential for innovation by analyzing an exhaustive genotype-phenotype map for a space of 1015 metabolisms that encodes all possible subsets of 51 reactions in central carbon metabolism. Using flux balance analysis, we predict the viability of these metabolisms on 10 different carbon sources which give rise to 1024 potential metabolic phenotypes. Although viable metabolisms with any one phenotype comprise a tiny fraction of genotype space, their absolute numbers exceed 109 for some phenotypes. Metabolisms with any one phenotype typically form a single network of genotypes that extends far or all the way through metabolic genotype space, where any two genotypes can be reached from each other through a series of single reaction changes. The minimal distance of genotype networks associated with different phenotypes is small, such that one can reach metabolisms with novel phenotypes – viable on new carbon sources – through one or few genotypic changes. Exceptions to these principles exist for those metabolisms whose complexity (number of reactions) is close to the minimum needed for viability. Increasing metabolic complexity enhances the potential for both evolutionary conservation and evolutionary innovation. PMID:26252881

Genotyping of Staphylococcus aureus in bovine mastitis and correlation to phenotypic characteristics.

PubMed

Artursson, Karin; Söderlund, Robert; Liu, Lihong; Monecke, Stefan; Schelin, Jenny

2016-09-25

Reducing the prevalence of mastitis caused by Staphylococcus aureus (S. aureus) is essential to improve animal health and reduce economic losses for farmers. The clinical outcome of acute mastitis and risk of progression to persistent mastitis can, at least to some extent, be related to genetic variants of the strain causing the infection. In the present study we have used microarrays to investigate the presence of virulence genes in S. aureus isolates from dairy cows with acute clinical mastitis (n=70) and correlated the findings to other genotypic and phenotypic characteristics. Among the most commonly found virulence factors were genes encoding several hemolysin types, leukocidins D and lukM/lukF-P83, clumping factors A and B, fibrinogen binding protein and fibronectin-binding protein A. Some virulence factors e.g. fibronectin-binding protein B and Staphylococcus aureus surface protein G were less common. Genes coding for several staphylococcal enterotoxins and toxic shock syndrome toxin-1 (TSST-1) were commonly found, especially in one major pulsotype. No beta-lactamase genes were found in any common pulsotype, while present in some rare pulsotypes, indicated to be of human origin. Production of TSST-1, enterotoxins, hemolysins and beta-lactamase could all be positively correlated to presence of the corresponding genes. This study reveals a number of genotypic differences and similarities among common and rare pulsotypes of S. aureus from cases of mastitis in Sweden. The results could help the design of diagnostic tools to guide on-farm interventions according to the expected impact on udder health from a specific S. aureus genotype. Copyright © 2016 Elsevier B.V. All rights reserved.

Breeding and Genetics Symposium: networks and pathways to guide genomic selection.

PubMed

Snelling, W M; Cushman, R A; Keele, J W; Maltecca, C; Thomas, M G; Fortes, M R S; Reverter, A

2013-02-01

Many traits affecting profitability and sustainability of meat, milk, and fiber production are polygenic, with no single gene having an overwhelming influence on observed variation. No knowledge of the specific genes controlling these traits has been needed to make substantial improvement through selection. Significant gains have been made through phenotypic selection enhanced by pedigree relationships and continually improving statistical methodology. Genomic selection, recently enabled by assays for dense SNP located throughout the genome, promises to increase selection accuracy and accelerate genetic improvement by emphasizing the SNP most strongly correlated to phenotype although the genes and sequence variants affecting phenotype remain largely unknown. These genomic predictions theoretically rely on linkage disequilibrium (LD) between genotyped SNP and unknown functional variants, but familial linkage may increase effectiveness when predicting individuals related to those in the training data. Genomic selection with functional SNP genotypes should be less reliant on LD patterns shared by training and target populations, possibly allowing robust prediction across unrelated populations. Although the specific variants causing polygenic variation may never be known with certainty, a number of tools and resources can be used to identify those most likely to affect phenotype. Associations of dense SNP genotypes with phenotype provide a 1-dimensional approach for identifying genes affecting specific traits; in contrast, associations with multiple traits allow defining networks of genes interacting to affect correlated traits. Such networks are especially compelling when corroborated by existing functional annotation and established molecular pathways. The SNP occurring within network genes, obtained from public databases or derived from genome and transcriptome sequences, may be classified according to expected effects on gene products. As illustrated by functionally informed genomic predictions being more accurate than naive whole-genome predictions of beef tenderness, coupling evidence from livestock genotypes, phenotypes, gene expression, and genomic variants with existing knowledge of gene functions and interactions may provide greater insight into the genes and genomic mechanisms affecting polygenic traits and facilitate functional genomic selection for economically important traits.

Adaptation to an extraordinary environment by evolution of phenotypic plasticity and genetic assimilation.

PubMed

Lande, Russell

2009-07-01

Adaptation to a sudden extreme change in environment, beyond the usual range of background environmental fluctuations, is analysed using a quantitative genetic model of phenotypic plasticity. Generations are discrete, with time lag tau between a critical period for environmental influence on individual development and natural selection on adult phenotypes. The optimum phenotype, and genotypic norms of reaction, are linear functions of the environment. Reaction norm elevation and slope (plasticity) vary among genotypes. Initially, in the average background environment, the character is canalized with minimum genetic and phenotypic variance, and no correlation between reaction norm elevation and slope. The optimal plasticity is proportional to the predictability of environmental fluctuations over time lag tau. During the first generation in the new environment the mean fitness suddenly drops and the mean phenotype jumps towards the new optimum phenotype by plasticity. Subsequent adaptation occurs in two phases. Rapid evolution of increased plasticity allows the mean phenotype to closely approach the new optimum. The new phenotype then undergoes slow genetic assimilation, with reduction in plasticity compensated by genetic evolution of reaction norm elevation in the original environment.

Phenotypic diversity, population structure and stress protein-based capacitoring in populations of Xeropicta derbentina, a heat-tolerant land snail species.

PubMed

Di Lellis, Maddalena A; Sereda, Sergej; Geißler, Anna; Picot, Adrien; Arnold, Petra; Lang, Stefanie; Troschinski, Sandra; Dieterich, Andreas; Hauffe, Torsten; Capowiez, Yvan; Mazzia, Christophe; Knigge, Thomas; Monsinjon, Tiphaine; Krais, Stefanie; Wilke, Thomas; Triebskorn, Rita; Köhler, Heinz-R

2014-11-01

The shell colour of many pulmonate land snail species is highly diverse. Besides a genetic basis, environmentally triggered epigenetic mechanisms including stress proteins as evolutionary capacitors are thought to influence such phenotypic diversity. In this study, we investigated the relationship of stress protein (Hsp70) levels with temperature stress tolerance, population structure and phenotypic diversity within and among different populations of a xerophilic Mediterranean snail species (Xeropicta derbentina). Hsp70 levels varied considerably among populations, and were significantly associated with shell colour diversity: individuals in populations exhibiting low diversity expressed higher Hsp70 levels both constitutively and under heat stress than those of phenotypically diverse populations. In contrast, population structure (cytochrome c oxidase subunit I gene) did not correlate with phenotypic diversity. However, genetic parameters (both within and among population differences) were able to explain variation in Hsp70 induction at elevated but non-pathologic temperatures. Our observation that (1) population structure had a high explanatory potential for Hsp70 induction and that (2) Hsp70 levels, in turn, correlated with phenotypic diversity while (3) population structure and phenotypic diversity failed to correlate provides empirical evidence for Hsp70 to act as a mediator between genotypic variation and phenotype and thus for chaperone-driven evolutionary capacitance in natural populations.

Genotype-phenotype correlation of xeroderma pigmentosum in a Chinese Han population.

PubMed

Sun, Z; Zhang, J; Guo, Y; Ni, C; Liang, J; Cheng, R; Li, M; Yao, Z

2015-04-01

Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by extreme sensitivity to sunlight, freckle-like pigmentation and a greatly increased incidence of skin cancers. Genetic mutation detection and genotype-phenotype analysis of XP are rarely reported in the Chinese Han population. To investigate the mutational spectrum of XP in a Chinese Han population, to discover any genotype-phenotype correlation and, consequently, to propose a simple and effective tool for the molecular diagnosis of XP. This study was carried out on 12 unrelated Chinese families that included 13 patients with clinically suspected XP. Genomic DNA was extracted from peripheral blood samples. Mutation screening was performed by direct sequencing of exons and flanking intron-exon boundaries for the entire coding region of eight XP genes. In 12 patients, direct sequencing of the whole coding region of eight XP genes revealed pathogenic mutations, including seven compound heterozygous mutations, three homozygous mutations and a Japanese founder mutation. Thirteen mutations have not been previously identified. This cohort was composed of four patients with XP-C (XPC), two with XP-G (ERCC5), three with XP-A (XPA) and three with XP-V (POLH). This study identified 13 novel mutations and extended the mutation spectrum of XP in the Chinese Han population. In this cohort, we found that patients with XP-G have no neurological symptoms, and patients with XP-A and XP-V have a high incidence of malignancy. Furthermore, lack of stringent protection against sunlight, late diagnosis and long duration of disease play an important role. © 2014 British Association of Dermatologists.

The genotype-phenotype landscape of familial amyotrophic lateral sclerosis in Australia.

PubMed

McCann, E P; Williams, K L; Fifita, J A; Tarr, I S; O'Connor, J; Rowe, D B; Nicholson, G A; Blair, I P

2017-09-01

Amyotrophic lateral sclerosis (ALS) is a clinically and genetically heterogeneous fatal neurodegenerative disease. Around 10% of ALS cases are hereditary. ALS gene discoveries have provided most of our understanding of disease pathogenesis. We aimed to describe the genetic landscape of ALS in Australia by assessing 1013 Australian ALS patients for known ALS mutations by direct sequencing, whole exome sequencing or repeat primed polymerase chain reaction. Age of disease onset and disease duration were used for genotype-phenotype correlations. We report 60.8% of Australian ALS families in this cohort harbour a known ALS mutation. Hexanucleotide repeat expansions in C9orf72 accounted for 40.6% of families and 2.9% of sporadic patients. We also report ALS families with mutations in SOD1 (13.7%), FUS (2.4%), TARDBP (1.9%), UBQLN2 (.9%), OPTN (.5%), TBK1 (.5%) and CCNF (.5%). We present genotype-phenotype correlations between these genes as well as between gene mutations. Notably, C9orf72 hexanucleotide repeat expansion positive patients experienced significantly later disease onset than ALS mutation patients. Among SOD1 families, p.I114T positive patients had significantly later onset and longer survival. Our report highlights a unique spectrum of ALS gene frequencies among patients from the Australian population, and further, provides correlations between specific ALS mutations with disease onset and/or duration. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Observation of c.260A > G mutation in superoxide dismutase 1 that causes p.Asn86Ser in Iranian amyotrophic lateral sclerosis patient and absence of genotype/phenotype correlation.

PubMed

Khani, Marzieh; Alavi, Afagh; Nafissi, Shahriar; Elahi, Elahe

2015-07-06

Amyotrophic lateral sclerosis (ALS) is the most common motor neuron disorder in European populations. ALS can be sporadic ALS (SALS) or familial ALS (FALS). Among 20 known ALS genes, mutations in C9orf72 and superoxide dismutase 1 (SOD1) are the most common genetic causes of the disease. Whereas C9orf72 mutations are more common in Western populations, the contribution of SOD1 to ALS in Iran is more than C9orf72. At present, a clear genotype/phenotype correlation for ALS has not been identified. We aimed to perform mutation screening of SOD1 in a newly identified Iranian FALS patient and to assess whether a genotype/phenotype correlation for the identified mutation exists. The five exons of SOD1 and flanking intronic sequences of a FALS proband were screened for mutations by direct sequencing. The clinical features of the proband were assessed by a neuromuscular specialist (SN). The phenotypic presentations were compared to previously reported patients with the same mutation. Heterozygous c.260A > G mutation in SOD1 that causes Asn86Ser was identified in the proband. Age at onset was 34 years and site of the first presentation was in the lower extremities. Comparisons of clinical features of different ALS patients with the same mutation evidenced variable presentations. The c.260A > G mutation in SOD1 that causes Asn86Ser appears to cause ALS with variable clinical presentations.

TreeGenes and CartograTree: Enabling visualization and analysis in forest tree genomics

Treesearch

E.S. Grau; S.A. Demurjian; H.A. Vasquez-Gross; D.G. Gessler; D.B. Neale; J.L. Wegrzyn

2017-01-01

Association studies integrating environmental, phenotypic, and genetic data are key in understanding forest tree resilience to climate change and disease. As genomic resources increase, both in terms of complete reference sequences and magnitude of individuals genotyped, researchers are better equipped to identify correlations between genetic variation and adaptive or...

[Phenotypic and genotypic characteristics of Mycobacterium kansasii strains isolated in Spain (2000-2003)].

PubMed

Jiménez-Pajares, María Soledad; Herrera, Laura; Valverde, Azucena; Saiz, Pilar; Sáez-Nieto, Juan Antonio

2005-05-01

Mycobacterium kansasii is an opportunistic pathogen that mainly causes pulmonary infections. This species accounted for 9.7% of Mycobacteria other than tuberculosis complex identified in the reference laboratory of the Spanish Centro Nacional de Microbiologia during the period of 2000-2003. In this study we analyzed the phenotypic and genotypic characteristics of 298 M. kansasii strains isolated over this 4-year period. The phenotypic characteristics were determined by conventional methods: biochemical testing, culture and morphological study. Genotypic characteristics were studied using PCR restriction fragment analysis of a fragment of the hsp65 gene and digestion with BstEII and HaeIII, according to the method of Telenti. Among the total of tested strains, 57.4% had the typical phenotypic characteristics described for M. kansasii. The rest had atypical patterns that we grouped into 17 biotypes. Strains belonging to six of the seven described genotypes were identified, with 86.6% of the strains falling into genotype I. Analysis of the phenotypic characteristics of M. kansasii showed a higher discrimination index for intraspecific differentiation than genotypic methods. Nevertheless, the high variability of phenotypic characteristics, some of which were very specific for the species (e.g., photochromogenicity), could complicate their identification. Hence both conventional and molecular methods should be used to accurately identify the atypical isolates.

Phenotype/genotype correlation in a case series of Stargardt's patients identifies novel mutations in the ABCA4 gene.

PubMed

Gemenetzi, M; Lotery, A J

2013-11-01

To investigate phenotypic variability in terms of best-corrected visual acuity (BCVA) in patients with Stargardt disease (STGD) and confirmed ABCA4 mutations. Entire coding region analysis of the ABCA4 gene by direct sequencing of seven patients with clinical findings of STGD seen in the Retina Clinics of Southampton Eye Unit between 2002 and 2011.Phenotypic variables recorded were BCVA, fluorescein angiographic appearance, electrophysiology, and visual fields. All patients had heterozygous amino acid-changing variants (missense mutations) in the ABCA4 gene. A splice sequence change was found in a 30-year-old patient with severly affected vision. Two novel sequence changes were identified: a missense mutation in a mildly affected 44-year-old patient and a frameshift mutation in a severly affected 34-year-old patient. The identified ABCA4 mutations were compatible with the resulting phenotypes in terms of BCVA. Higher BCVAs were recorded in patients with missense mutations. Sequence changes, predicted to have more deleterious effect on protein function, resulted in a more severe phenotype. This case series of STGD patients demonstrates novel genotype/phenotype correlations, which may be useful to counselling of patients. This information may prove useful in selection of candidates for clinical trials in ABCA4 disease.

Phenotype and genotype in 101 males with X-linked creatine transporter deficiency.

PubMed

van de Kamp, J M; Betsalel, O T; Mercimek-Mahmutoglu, S; Abulhoul, L; Grünewald, S; Anselm, I; Azzouz, H; Bratkovic, D; de Brouwer, A; Hamel, B; Kleefstra, T; Yntema, H; Campistol, J; Vilaseca, M A; Cheillan, D; D'Hooghe, M; Diogo, L; Garcia, P; Valongo, C; Fonseca, M; Frints, S; Wilcken, B; von der Haar, S; Meijers-Heijboer, H E; Hofstede, F; Johnson, D; Kant, S G; Lion-Francois, L; Pitelet, G; Longo, N; Maat-Kievit, J A; Monteiro, J P; Munnich, A; Muntau, A C; Nassogne, M C; Osaka, H; Ounap, K; Pinard, J M; Quijano-Roy, S; Poggenburg, I; Poplawski, N; Abdul-Rahman, O; Ribes, A; Arias, A; Yaplito-Lee, J; Schulze, A; Schwartz, C E; Schwenger, S; Soares, G; Sznajer, Y; Valayannopoulos, V; Van Esch, H; Waltz, S; Wamelink, M M C; Pouwels, P J W; Errami, A; van der Knaap, M S; Jakobs, C; Mancini, G M; Salomons, G S

2013-07-01

Creatine transporter deficiency is a monogenic cause of X-linked intellectual disability. Since its first description in 2001 several case reports have been published but an overview of phenotype, genotype and phenotype--genotype correlation has been lacking. We performed a retrospective study of clinical, biochemical and molecular genetic data of 101 males with X-linked creatine transporter deficiency from 85 families with a pathogenic mutation in the creatine transporter gene (SLC6A8). Most patients developed moderate to severe intellectual disability; mild intellectual disability was rare in adult patients. Speech language development was especially delayed but almost a third of the patients were able to speak in sentences. Besides behavioural problems and seizures, mild to moderate motor dysfunction, including extrapyramidal movement abnormalities, and gastrointestinal problems were frequent clinical features. Urinary creatine to creatinine ratio proved to be a reliable screening method besides MR spectroscopy, molecular genetic testing and creatine uptake studies, allowing definition of diagnostic guidelines. A third of patients had a de novo mutation in the SLC6A8 gene. Mothers with an affected son with a de novo mutation should be counselled about a recurrence risk in further pregnancies due to the possibility of low level somatic or germline mosaicism. Missense mutations with residual activity might be associated with a milder phenotype and large deletions extending beyond the 3' end of the SLC6A8 gene with a more severe phenotype. Evaluation of the biochemical phenotype revealed unexpected high creatine levels in cerebrospinal fluid suggesting that the brain is able to synthesise creatine and that the cerebral creatine deficiency is caused by a defect in the reuptake of creatine within the neurones.

Phenotype/genotype correlations in Gaucher disease type 1: Clinical and therapeutic implications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sibille, A.; Eng, C.M.; Kim, S.J.

1993-06-01

Gaucher disease is the most frequent lysosomal storage disease and the most prevalent genetic disease among Ashkenazi Jews. Gaucher disease type 1 is characterized by marked variability of the phenotype and by the absence of neuronopathic involvement. To test the hypothesis that this phenotypic variability was due to genetic compounds of several different mutant alleles, 161 symptomatic patients with Gaucher disease type 1 (> 90% Ashkenazi Jewish) were analyzed for clinical involvement, and their genotypes were determined. Qualitative and quantitative measures of disease involvement included age at onset of the disease manifestations, hepatic and splenic volumes, age at splenectomy, andmore » severity of bony disease. High statistically significant differences (P < .005) were found in each clinical parameter in patients with the N370S/N370S genotype compared with those patients with the N370S/84GG, N370S/L444P, and N370/ genotypes. The symptomatic N370S homozygotes had onset of their disease two to three decades later than patients with the other genotypes. In addition, patients with the latter genotypes have much more severely involved livers, spleens, and bones and had a higher incidence of splenectomy at an earlier age. These predictive genotype analyses provide the basis for genetic care delivery and therapeutic recommendations in patients affected with Gaucher disease type 1. 38 refs., 1 fig., 4 tabs.« less

Network-based analysis of genotype-phenotype correlations between different inheritance modes.

PubMed

Hao, Dapeng; Li, Chuanxing; Zhang, Shaojun; Lu, Jianping; Jiang, Yongshuai; Wang, Shiyuan; Zhou, Meng

2014-11-15

Recent studies on human disease have revealed that aberrant interaction between proteins probably underlies a substantial number of human genetic diseases. This suggests a need to investigate disease inheritance mode using interaction, and based on which to refresh our conceptual understanding of a series of properties regarding inheritance mode of human disease. We observed a strong correlation between the number of protein interactions and the likelihood of a gene causing any dominant diseases or multiple dominant diseases, whereas no correlation was observed between protein interaction and the likelihood of a gene causing recessive diseases. We found that dominant diseases are more likely to be associated with disruption of important interactions. These suggest inheritance mode should be understood using protein interaction. We therefore reviewed the previous studies and refined an interaction model of inheritance mode, and then confirmed that this model is largely reasonable using new evidences. With these findings, we found that the inheritance mode of human genetic diseases can be predicted using protein interaction. By integrating the systems biology perspectives with the classical disease genetics paradigm, our study provides some new insights into genotype-phenotype correlations. haodapeng@ems.hrbmu.edu.cn or biofomeng@hotmail.com Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Pathologic findings in breast, fallopian tube, and ovary specimens in non-BRCA hereditary breast and/or ovarian cancer syndromes: a study of 18 patients with deleterious germline mutations in RAD51C, BARD1, BRIP1, PALB2, MUTYH, or CHEK2.

PubMed

Schoolmeester, J Kenneth; Moyer, Ann M; Goodenberger, McKinsey L; Keeney, Gary L; Carter, Jodi M; Bakkum-Gamez, Jamie N

2017-12-01

Germline BRCA mutations account for a significant proportion of genetic/familial risk of breast and ovarian cancer (GBOC) susceptibility, but a broader spectrum of GBOC susceptibility genes has emerged in recent years. Genotype-to-phenotype correlations are known for some established forms of GBOC; however, whether such correlations exist for less common GBOC variants is unclear. We reviewed our institution's experience with non-BRCA GBOC, looking specifically for trends in pathologic and clinical features. Eighteen women with deleterious germline mutations in RAD51C (5 patients), BARD1 (1 patient), BRIP1 (2 patients), PALB2 (3 patients), MUTYH (2 patients), or CHEK2 (5 patients) were identified between January 2011 and December 2016. Thirteen (72%) of 18 patients developed carcinoma of the breast, fallopian tube, or ovary, with 1 patient developing 2 separate primary neoplasms. Twelve (86%) of 14 tumors occurred in the breast. One (7%) arose in the fallopian tube and another (7%) arose in the ovary. Evidence of genotype-phenotype correlation was not identified. However, some data suggest that the type of alteration in select genes may influence tumor behavior and patient outcome. In our PALB2 mutation cohort, 2 patients with frameshift mutations led to early onset and rapid progression to stage IV breast cancer in contrast to stage IA breast cancer in 1 patient with a nonsense mutation. Despite no apparent genotype-phenotype trends, our data indicate that some loss-of-function variants in PALB2 may lead to differences in tumor behavior and patient outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

Compound Heterozygosity for Hb Alperton (HBB: c.407C>T) and IVS-I-5 (G>C) (HBB: c.92+5G>C) Mutations Presenting as a Moderate Anemia in an Indian Family.

PubMed

Godbole, Koumudi G; Ramachandran, Angelina; Karkamkar, Ashwini S; Dalal, Ashwin B

2018-04-13

While knowledge of HBB gene mutations is necessary for offering prenatal diagnosis (PND) of β-thalassemia (β-thal), a genotype-phenotype correlation may not always be available for rare variants. We present for the first time, genotype-phenotype correlation for a compound heterozygous status with IVS-I-5 (G>C) (HBB: c.92+5G>C) and HBB: c.407C>T (Hb Alperton) mutations on the HBB gene in an Indian family. Hb Alperton is a very rare hemoglobin (Hb) variant with scant published information about its clinical presentation, especially when accompanied with another HBB gene mutation. Here we provide biochemical as well as clinical details of this variant.

Assessment of Vegetation Indices Derived by UAV Imagery for Durum Wheat Phenotyping under a Water Limited and Heat Stressed Mediterranean Environment.

PubMed

Kyratzis, Angelos C; Skarlatos, Dimitrios P; Menexes, George C; Vamvakousis, Vasileios F; Katsiotis, Andreas

2017-01-01

There is growing interest for using Spectral Vegetation Indices (SVI) derived by Unmanned Aerial Vehicle (UAV) imagery as a fast and cost-efficient tool for plant phenotyping. The development of such tools is of paramount importance to continue progress through plant breeding, especially in the Mediterranean basin, where climate change is expected to further increase yield uncertainty. In the present study, Normalized Difference Vegetation Index (NDVI), Simple Ratio (SR) and Green Normalized Difference Vegetation Index (GNDVI) derived from UAV imagery were calculated for two consecutive years in a set of twenty durum wheat varieties grown under a water limited and heat stressed environment. Statistically significant differences between genotypes were observed for SVIs. GNDVI explained more variability than NDVI and SR, when recorded at booting. GNDVI was significantly correlated with grain yield when recorded at booting and anthesis during the 1st and 2nd year, respectively, while NDVI was correlated to grain yield when recorded at booting, but only for the 1st year. These results suggest that GNDVI has a better discriminating efficiency and can be a better predictor of yield when recorded at early reproductive stages. The predictive ability of SVIs was affected by plant phenology. Correlations of grain yield with SVIs were stronger as the correlations of SVIs with heading were weaker or not significant. NDVIs recorded at the experimental site were significantly correlated with grain yield of the same set of genotypes grown in other environments. Both positive and negative correlations were observed indicating that the environmental conditions during grain filling can affect the sign of the correlations. These findings highlight the potential use of SVIs derived by UAV imagery for durum wheat phenotyping under low yielding Mediterranean conditions.

Expressivity of hearing loss in cases with Usher syndrome type IIA.

PubMed

Sadeghi, André M; Cohn, Edward S; Kimberling, William J; Halvarsson, Glenn; Möller, Claes

2013-12-01

The purpose of this study was to compare the genotype/phenotype relationship between siblings with identical USH2A pathologic mutations and the consequent audiologic phenotypes, in particular degree of hearing loss (HL). Decade audiograms were also compared among two groups of affected subjects with different mutations of USH2A. DNA samples from patients with Usher syndrome type II were analysed. The audiological features of patients and affected siblings with USH2A mutations were also examined to identify genotype-phenotype correlations. Genetic and audiometric examinations were performed in 18 subjects from nine families with Usher syndrome type IIA. Three different USH2A mutations were identified in the affected subjects. Both similarities and differences of the auditory phenotype were seen in families with several affected siblings. A variable degree of hearing loss, ranging from mild to profound, was observed among affected subjects. No significant differences in hearing thresholds were found the group of affected subjects with different pathological mutations. Our results indicate that mutations in the USH2A gene and the resulting phenotype are probably modulated by other variables, such as modifying genes, epigenetics or environmental factors which may be of importance for better understanding the etiology of Usher syndrome.

Tag-mediated cooperation with non-deterministic genotype-phenotype mapping

NASA Astrophysics Data System (ADS)

Zhang, Hong; Chen, Shu

2016-01-01

Tag-mediated cooperation provides a helpful framework for resolving evolutionary social dilemmas. However, most of the previous studies have not taken into account genotype-phenotype distinction in tags, which may play an important role in the process of evolution. To take this into consideration, we introduce non-deterministic genotype-phenotype mapping into a tag-based model with spatial prisoner's dilemma. By our definition, the similarity between genotypic tags does not directly imply the similarity between phenotypic tags. We find that the non-deterministic mapping from genotypic tag to phenotypic tag has non-trivial effects on tag-mediated cooperation. Although we observe that high levels of cooperation can be established under a wide variety of conditions especially when the decisiveness is moderate, the uncertainty in the determination of phenotypic tags may have a detrimental effect on the tag mechanism by disturbing the homophilic interaction structure which can explain the promotion of cooperation in tag systems. Furthermore, the non-deterministic mapping may undermine the robustness of the tag mechanism with respect to various factors such as the structure of the tag space and the tag flexibility. This observation warns us about the danger of applying the classical tag-based models to the analysis of empirical phenomena if genotype-phenotype distinction is significant in real world. Non-deterministic genotype-phenotype mapping thus provides a new perspective to the understanding of tag-mediated cooperation.

Altered Trafficking and Processing of GALC Mutants Correlates with Globoid Cell Leukodystrophy Severity

PubMed Central

Feltri, M. Laura; Wrabetz, Lawrence

2016-01-01

Globoid cell leukodystrophy (GLD, Krabbe disease) is due to autosomal recessive mutations in the lysosomal enzyme galactosylceramidase (GALC). Many GLD patients develop infantile-onset of progressive neurologic deterioration and death by 2 years of age, whereas others have a later-onset, milder disease. Cord blood transplant slows disease progression much more effectively when performed presymptomatically, highlighting the importance of early diagnosis. Current diagnosis is based on reduced GALC activity, DNA sequence, and clinical examination. However, presymptomatic diagnosis is hampered by imperfect genotype-GALC activity-phenotype correlations. In addition, three polymorphisms in the GALC gene are variably associated with disease mutations and have unknown effects on GALC activity and disease outcome. Here, we study mutations that cause infantile or later-onset GLD, and show that GALC activity is significantly lower in infantile versus later-onset mutants when measured in the lysosomal fraction, but not in whole-cell lysates. In parallel, infantile-onset mutant GALCs showed reduced trafficking to lysosomes and processing than later-onset mutant GALCs. Finally, the cis-polymorphisms also affected trafficking to the lysosome and processing of GALC. These differences potentially explain why the activity of different mutations appears similar in whole-cell extracts from lymphocytes, and suggest that measure of GALC activity in lysosomes may better predict the onset and severity of disease for a given GLD genotype. SIGNIFICANCE STATEMENT Globoid cell leukodystrophy (GLD, Krabbe disease) is diagnosed by measuring galactosylceramidase (GALC) activity and DNA analysis. However, genotype and phenotype often do not correlate due to considerable clinical variability, even for the same mutation, for unknown reasons. We find that altered trafficking to the lysosome and processing of GALC correlates with GLD severity and is modulated by cis-polymorphisms. Current diagnosis of GLD is based on GALC activity of total cell lysates from blood, which does not discriminate whether the activity comes from the lysosome or other subcellular organelles. Measurement of GALC activity in lysosomes may predict which infants are at high risk for the infantile phenotype while distinguishing other children who will develop later-onset phenotypes without onset of symptoms for years. PMID:26865610

Mild phenotype associated with Inv Dup 8 (q21.2-q22.3) of maternal origin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tupler, R.; Pagliano, E.; Barbierato, L.

1996-03-15

We report on a girl with a de novo inverted duplication of chromosome 8 (q21.2-q22.3) associated with a mild phenotype. We were able to establish the maternal origin of the rearranged chromosome. We discuss the correlation between genotype and phenotype on the basis of a review of the findings from individuals with partial dup(8q). 6 refs., 4 figs.

Genetic basis for correction of very-long-chain acyl-coenzyme A dehydrogenase deficiency by bezafibrate in patient fibroblasts: toward a genotype-based therapy.

PubMed

Gobin-Limballe, S; Djouadi, F; Aubey, F; Olpin, S; Andresen, B S; Yamaguchi, S; Mandel, H; Fukao, T; Ruiter, J P N; Wanders, R J A; McAndrew, R; Kim, J J; Bastin, J

2007-12-01

Very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency is an inborn mitochondrial fatty-acid beta-oxidation (FAO) defect associated with a broad mutational spectrum, with phenotypes ranging from fatal cardiopathy in infancy to adolescent-onset myopathy, and for which there is no established treatment. Recent data suggest that bezafibrate could improve the FAO capacities in beta-oxidation-deficient cells, by enhancing the residual level of mutant enzyme activity via gene-expression stimulation. Since VLCAD-deficient patients frequently harbor missense mutations with unpredictable effects on enzyme activity, we investigated the response to bezafibrate as a function of genotype in 33 VLCAD-deficient fibroblasts representing 45 different mutations. Treatment with bezafibrate (400 microM for 48 h) resulted in a marked increase in FAO capacities, often leading to restoration of normal values, for 21 genotypes that mainly corresponded to patients with the myopathic phenotype. In contrast, bezafibrate induced no changes in FAO for 11 genotypes corresponding to severe neonatal or infantile phenotypes. This pattern of response was not due to differential inductions of VLCAD messenger RNA, as shown by quantitative real-time polymerase chain reaction, but reflected variable increases in measured VLCAD residual enzyme activity in response to bezafibrate. Genotype cross-analysis allowed the identification of alleles carrying missense mutations, which could account for these different pharmacological profiles and, on this basis, led to the characterization of 9 mild and 11 severe missense mutations. Altogether, the responses to bezafibrate reflected the severity of the metabolic blockage in various genotypes, which appeared to be correlated with the phenotype, thus providing a new approach for analysis of genetic heterogeneity. Finally, this study emphasizes the potential of bezafibrate, a widely prescribed hypolipidemic drug, for the correction of VLCAD deficiency and exemplifies the integration of molecular information in a therapeutic strategy.

Relative Contribution of Mutations in Genes for Autosomal Dominant Distal Hereditary Motor Neuropathies: A Genotype-Phenotype Correlation Study

ERIC Educational Resources Information Center

Dierick, Ines; Baets, Jonathan; Irobi, Joy; Jacobs, An; De Vriendt, Els; Deconinck, Tine; Merlini, Luciano; Van den Bergh, Peter; Rasic, Vedrana Milic; Robberecht, Wim; Fischer, Dirk; Morales, Raul Juntas; Mitrovic, Zoran; Seeman, Pavel; Mazanec, Radim; Kochanski, Andrzej; Jordanova, Albena; Auer-Grumbach, Michaela; Helderman-van den Enden, A. T. J. M.; Wokke, John H. J.; Nelis, Eva; De Jonghe, Peter; Timmerman, Vincent

2008-01-01

Distal hereditary motor neuropathy (HMN) is a clinically and genetically heterogeneous group of disorders affecting spinal alpha-motor neurons. Since 2001, mutations in six different genes have been identified for autosomal dominant distal HMN; "glycyl-tRNA synthetase (GARS)," "dynactin 1 (DCTN1)," "small heat shock 27 kDa…

Determination of resistance and virulence genes in Enterococcus faecalis and E. faecium strains isolated from poultry and their genotypic characterization by ADSRRS-fingerprinting.

PubMed

Nowakiewicz, A; Ziólkowska, G; Troscianczyk, A; Zieba, P; Gnat, S

2017-04-01

The aim of this study was to determine the antimicrobial resistance of E. faecalis and E. faecium strains isolated from poultry and to carry out genotypic characterization thereof with the ADSRRS-fingerprinting method (amplification of DNA fragments surrounding rare restriction sites) and analysis of the genetic relatedness between the isolates with different resistance and virulence determinants. Samples were collected from 70 4-week-old chickens and tested for Enterococcus. Minimum inhibitory concentrations of 11 antimicrobials were determined using the broth microdilution method. Detection of antibiotic resistance and virulence genes was performed using PCR, and molecular analysis was carried out using the ADSRRS-fingerprinting method. The highest percentage of strains was resistant to tetracycline (60.5%) and erythromycin (54.4%), and a large number exhibited high-level resistance to both kanamycin (42.1%) and streptomycin (34.2%). Among 8 genes encoding AME, the tested strains showed mainly the presence of [aph(3΄)-IIIa], [ant(6)-Ia], [aac(6΄)-Ie-aph(2΄΄)-Ia], and [ant(9)-Ia] genes. Phenotypic resistance to erythromycin was encoded in 98.4% strains by the ermB gene. Genotypic resistance to tetracycline in E. faecium was associated with the presence of tetM and tetL (respectively, in 95.5 and 57.7% of the isolates); in contrast, E. faecalis strains were characterized mainly by the presence of tetO (83.3%). The virulence profile was homogenous for all E. faecium strains and included only efaAfm and ccf genes. All E. faecalis strains exhibited efaAfs, gelE, and genes encoding sex pheromones. The strains tested exhibited 34 genotypic profiles. Comparative analysis of phenotypic and genotypic resistance and virulence profiles and confrontation thereof with the genotypes of the strains tested showed that strains assigned to a particular genotype have an identical phenotypic resistance profile and a panel of resistance and virulence genes. The results of this study confirm that poultry can be a reservoir of resistant E. faecium and E. faecalis strains with multiple combinations of resistance and virulence genes, whose specific panel determines not only phenotypic characteristics but also has a strong correlation with the genotypic profiles of the strains. © 2016 Poultry Science Association Inc.

Genetics Home Reference: erythromelalgia

MedlinePlus

... Bennett DL, Wood JN, Kinali M. Novel mutations mapping to the fourth sodium channel domain of Nav1. ... and late-onset inherited erythromelalgia: genotype-phenotype correlation. Brain. 2009 Jul;132(Pt 7):1711-22. doi: ...

To Genotype or Phenotype for Personalized Medicine? CYP450 Drug Metabolizing Enzyme Genotype-Phenotype Concordance and Discordance in the Ecuadorian Population.

PubMed

De Andrés, Fernando; Terán, Santiago; Hernández, Francisco; Terán, Enrique; LLerena, Adrián

2016-12-01

Genetic variations within the cytochrome P450 (CYP450) superfamily of drug metabolizing enzymes confer substantial person-to-person and between-population differences in pharmacokinetics, and by extension, highly variable clinical effects of medicines. In this context, "personalized medicine," "precision medicine," and "stratified medicine" are related concepts attributed to what is essentially targeted therapeutics and companion diagnostics, aimed at improving safety and effectiveness of health interventions. We report here, to the best of our knowledge, the first comparative clinical pharmacogenomics study, in an Ecuadorian population sample, of five key CYP450s involved in drug metabolism: CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4. In 139 unrelated, medication-free, and healthy Ecuadorian subjects, we measured the phenotypic activity of these drug metabolism pathways using the CEIBA multiplexed phenotyping cocktail. The subjects were genotyped for each CYP450 enzyme gene as well. Notably, based on the CYP450 metabolic phenotypes estimated by the genotype data, 0.75% and 3.10% of the subjects were genotypic poor metabolizers (gPMs) for CYP2C19 and CYP2D6, respectively. Additionally, on the other extreme, genotype-estimated ultrarapid metabolizer (gUMs) phenotype was represented by 15.79% of CYP2C19, and 5.43% of CYP2D6. There was, however, considerable discordance between directly measured phenotypes (mPMs and mUMs) and the above genotype-estimated enzyme phenotypes. For example, among individuals genotypically carrying enhanced activity alleles (gUMs), many showed a lower actual drug metabolism capacity than expected by their genotypes, even lower than individuals with reduced or no activity alleles. In conclusion, for personalized medicine in the Ecuadorian population, we recommend CYP450 multiplexed phenotyping, or genotyping and phenotyping in tandem, rather than CYP450 genotypic tests alone. Additionally, we recommend, in consideration of equity, ethical, and inclusive representation in global science, further precision medicine research and funding in support of neglected or understudied populations worldwide.

Stay-green traits to improve wheat adaptation in well-watered and water-limited environments

PubMed Central

Christopher, John.T.; Christopher, Mandy J.; Borrell, Andrew K.; Fletcher, Susan; Chenu, Karine

2016-01-01

A stay-green phenotype enables crops to retain green leaves longer after anthesis compared with senescent types, potentially improving yield. Measuring the normalized difference vegetative index (NDVI) during the whole senescence period allows quantification of component stay-green traits contributing to a stay-green phenotype. These objective and standardized traits can be compared across genotypes and environments. Traits examined include maximum NDVI near anthesis (Nmax), senescence rate (SR), a trait integrating senescence (SGint), plus time from anthesis to onset (OnS), mid-point (MidS), and near completion (EndS) of senescence. The correlation between stay-green traits and yield was studied in eight contrasting environments ranging from well watered to severely water limited. Environments were each classified into one of the four major drought environment types (ETs) previously identified for the Australian wheat cropping system. SGint, OnS, and MidS tended to have higher values in higher yielding environments for a given genotype, as well as for higher yielding genotypes within a given environment. Correlation between specific stay-green traits and yield varied with ET. In the studied population, SGint, OnS, and MidS strongly correlated with yield in three of the four ETs which included well-watered environments (0.43–0.86), but less so in environments with only moderate water-stress after anthesis (−0.03 to 0.31). In contrast, Nmax was most highly correlated with yield under moderate post-anthesis water stress (0.31–0.43). Selection for particular stay-green traits, combinations of traits, and/or molecular markers associated with the traits could enhance genetic progress toward stay-green wheats with higher, more stable yield in both well-watered and water-limited conditions. PMID:27443279

The Monarch Initiative: an integrative data and analytic platform connecting phenotypes to genotypes across species

PubMed Central

Mungall, Christopher J.; McMurry, Julie A.; Köhler, Sebastian; Balhoff, James P.; Borromeo, Charles; Brush, Matthew; Carbon, Seth; Conlin, Tom; Dunn, Nathan; Engelstad, Mark; Foster, Erin; Gourdine, J.P.; Jacobsen, Julius O.B.; Keith, Dan; Laraway, Bryan; Lewis, Suzanna E.; NguyenXuan, Jeremy; Shefchek, Kent; Vasilevsky, Nicole; Yuan, Zhou; Washington, Nicole; Hochheiser, Harry; Groza, Tudor; Smedley, Damian; Robinson, Peter N.; Haendel, Melissa A.

2017-01-01

The correlation of phenotypic outcomes with genetic variation and environmental factors is a core pursuit in biology and biomedicine. Numerous challenges impede our progress: patient phenotypes may not match known diseases, candidate variants may be in genes that have not been characterized, model organisms may not recapitulate human or veterinary diseases, filling evolutionary gaps is difficult, and many resources must be queried to find potentially significant genotype–phenotype associations. Non-human organisms have proven instrumental in revealing biological mechanisms. Advanced informatics tools can identify phenotypically relevant disease models in research and diagnostic contexts. Large-scale integration of model organism and clinical research data can provide a breadth of knowledge not available from individual sources and can provide contextualization of data back to these sources. The Monarch Initiative (monarchinitiative.org) is a collaborative, open science effort that aims to semantically integrate genotype–phenotype data from many species and sources in order to support precision medicine, disease modeling, and mechanistic exploration. Our integrated knowledge graph, analytic tools, and web services enable diverse users to explore relationships between phenotypes and genotypes across species. PMID:27899636

Generalized epilepsy and mild intellectual disability associated with 13q34 deletion: A potential role for SOX1 and ARHGEF7.

PubMed

Orsini, A; Bonuccelli, A; Striano, P; Azzara, A; Costagliola, G; Consolini, R; Peroni, D G; Valetto, A; Bertini, V

2018-04-26

Terminal deletions of long arm of chromosome 13 are rare and poorly characterized by cytogenetic studies, making for difficult genotype-phenotype correlations. We report two siblings presenting generalized epilepsy, intellectual disability, and genitourinary tract defects. Array CGH detected a 1.3 Mb deletion at 13q34; it contains two protein-coding genes, SOX1 and ARHGEF7, whose haploinsufficiency can contribute to the epileptic phenotype. Copyright © 2018 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Clinical aspects of Usher syndrome and the USH2A gene in a cohort of 433 patients.

PubMed

Blanco-Kelly, Fiona; Jaijo, Teresa; Aller, Elena; Avila-Fernandez, Almudena; López-Molina, María Isabel; Giménez, Ascensión; García-Sandoval, Blanca; Millán, José M; Ayuso, Carmen

2015-02-01

A new statistical approach is needed to describe the clinical differences between type I and type II Usher syndrome and between the 2 most frequent mutations in the USH2A gene. To describe the primary phenotypic characteristics and differences between type I and type II Usher syndrome and to establish a phenotype-genotype correlation for the 2 most frequent mutations in the USH2A gene. Cross-sectional study at a genetics department, in which clinical evaluations were performed for 433 patients (297 unrelated families) who were classified as having type I, II, III, atypical, or unclassified Usher syndrome according to their clinical history, pedigree data, results from ophthalmological studies, and audiological, neurophysiological, and vestibular test results. Molecular studies were performed for 304 patients (256 unrelated families). The Mann-Whitney U test or the χ2 test was used for calculating the differences between mean values for the analyzed parameters. Age at diagnosis; age at onset of night blindness, visual field loss, visual acuity loss, and cataracts; and severity and age at diagnosis of hearing loss. The comparison between patients with type I Usher syndrome and those with type II Usher syndrome revealed P < .001 for most items analyzed. The most frequent mutations in the USH2A gene were the p.Glu767Serfs*21 and p.Cys759Phe mutations, with an allelic frequency of 23.2% (63 of 272 alleles) and 8.1% (22 of 272 alleles), respectively. The phenotypic analysis for patients carrying p.Cys759Phe showed P < .001 for most items analyzed when compared with patients carrying p.Glu767Serfs*21 and when compared with patients carrying other mutations in the USH2A gene. None of the p.Cys759Phe patients exhibited a severe hearing loss phenotype, and more than 60% had only mild hearing loss. Most patients carrying the p.Glu767Serfs*21 mutation (72.1%) were moderately deaf. Our study presents the clinical differences between type I and type II Usher syndrome and between the 2 most frequent mutations in the USH2A gene. Detailed genotype-phenotype correlations, as presented in our study, allow for a better correlation of clinical signs with a known genotype and can improve the clinical management, genetic counseling, and risk assessment of patients with Usher syndrome because an estimated prognosis of their disease can be made.

Mutational robustness accelerates the origin of novel RNA phenotypes through phenotypic plasticity.

PubMed

Wagner, Andreas

2014-02-18

Novel phenotypes can originate either through mutations in existing genotypes or through phenotypic plasticity, the ability of one genotype to form multiple phenotypes. From molecules to organisms, plasticity is a ubiquitous feature of life, and a potential source of exaptations, adaptive traits that originated for nonadaptive reasons. Another ubiquitous feature is robustness to mutations, although it is unknown whether such robustness helps or hinders the origin of new phenotypes through plasticity. RNA is ideal to address this question, because it shows extensive plasticity in its secondary structure phenotypes, a consequence of their continual folding and unfolding, and these phenotypes have important biological functions. Moreover, RNA is to some extent robust to mutations. This robustness structures RNA genotype space into myriad connected networks of genotypes with the same phenotype, and it influences the dynamics of evolving populations on a genotype network. In this study I show that both effects help accelerate the exploration of novel phenotypes through plasticity. My observations are based on many RNA molecules sampled at random from RNA sequence space, and on 30 biological RNA molecules. They are thus not only a generic feature of RNA sequence space but are relevant for the molecular evolution of biological RNA. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

A multifamily study on the relationship between CYP2C19 genotype and s-mephenytoin oxidation phenotype.

PubMed

Brøsen, K; de Morais, S M; Meyer, U A; Goldstein, J A

1995-10-01

It has recently been shown that the most common mutation (named m1) in both Caucasian and Japanese poor metabolizers (PM) of S-mephenytoin is a single base pair mutation (G-->A) in exon 5 of the CYP2C19 gene. In Japanese, a second defective allele of CYP2C19 named m2 consists of a G-->A mutation in exon 4. In the present study, we have investigated the inheritance of the CYP2C19 wild type allele (wt) and the two defective alleles (m1 and m2) in families of 11 Danish PM probands. The study was carried out for two principal reasons. First, we wanted to confirm the autosomal recessive inheritance of the defective alleles, and second, we wanted to examine the specificity and sensitivity of the CYP2C19 genotyping test. Individuals were phenotyped by measuring the ratio of S/R mephenytoin excreted in the urine after administration of mephenytoin, and genotyping was carried out by a PCR-based DNA amplification procedure. The genotypes of nine of the 11 probands were consistent with their phenotypes. Eight were homozygous m1/m1, and one was heterozygous m1/m2. The genotypes of two putative PM probands (wt/m1) were not consistent with their phenotypes. On the basis of extended phenotyping (additional late urine collections (24-36 h) and acidification of urine), one of these could probably be reclassified as an extensive metabolizer (EM) while the other was considered to be a true PM. This suggests the presence of an additional unknown mutant allele in the latter. Seven of the 41 phenotyped relatives in the 11 families were phenotyped as PMs, and with the exception of the father of family 10, their genotypes (m1/m1) were consistent with their phenotypes. Extended phenotyping (acidification of urine) suggested that the father of family 10 in fact is an EM and hence that his genotype (wt/m1) is concordant with his phenotype. Thus, the specificity of genotyping tests for PM was 100%, while the sensitivity was 15/16 or 94%. Our study provides unequivocal evidence for autosomal recessive inheritance of the PM trait.

Phenotypic and genome-wide association analysis of spike ethylene in diverse wheat genotypes under heat stress.

PubMed

Valluru, Ravi; Reynolds, Matthew P; Davies, William J; Sukumaran, Sivakumar

2017-04-01

The gaseous phytohormone ethylene plays an important role in spike development in wheat (Triticum aestivum). However, the genotypic variation and the genomic regions governing spike ethylene (SET) production in wheat under long-term heat stress remain unexplored. We investigated genotypic variation in the production of SET and its relationship with spike dry weight (SDW) in 130 diverse wheat elite lines and landraces under heat-stressed field conditions. We employed an Illumina iSelect 90K single nucleotide polymorphism (SNP) genotyping array to identify the genetic loci for SET and SDW through a genome-wide association study (GWAS) in a subset of the Wheat Association Mapping Initiative (WAMI) panel. The SET and SDW exhibited appreciable genotypic variation among wheat genotypes at the anthesis stage. There was a strong negative correlation between SET and SDW. The GWAS uncovered five and 32 significant SNPs for SET, and 22 and 142 significant SNPs for SDW, in glasshouse and field conditions, respectively. Some of these SNPs closely localized to the SNPs for plant height, suggesting close associations between plant height and spike-related traits. The phenotypic and genetic elucidation of SET and its relationship with SDW supports future efforts toward gene discovery and breeding wheat cultivars with reduced ethylene effects on yield under heat stress. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Interrelationship and path coefficient analysis of yield components in F4 progenies of tef (Eragrostis tef).

PubMed

Debebe, Abel; Singh, Harijat; Tefera, Hailu

2014-01-01

This experiment was conducted at Debre Zeit and Akaki during 2004-2005 cropping season on F2-derived F4 bulk families of three crosses, viz, DZ-01-974 x DZ-01-2786, DZ-01-974 x DZ-Cr-37 and Alba x Kaye Murri. To estimate the correlations and path coefficients between yield and yield components, 63 F4 families were taken randomly from each of the three crosses. The 189 F4 families, five parents and two checks were space planted following in 14 x 14 simple lattice design. Study of associations among traits indicated that yield was positively associated with shoot biomass, harvest index, lodging index and panicle kernel weight at phenotypic level at Debre Zeit. At Akaki, yield had significant positive correlation with shoot biomass, harvest index, plant height, panicle length and panicle weight. At genotypic level, grain yield per plot exhibited positive association with harvest index, shoot biomass, lodging index and panicle kernel weight at Debre Zeit. By contrast, days to heading, days to maturity, plant height and panicle length showed negative association with yield. At Akaki, kernel yield per plot was positively correlated at genotypic level with all the traits considered where lodging index had the highest correlation followed by shoot biomass, panicle kernel weight and harvest index. Path coefficient analysis at both phenotypic and genotypic levels for both the locations suggested those shoot biomass and harvest indexes are the two important yield determining traits. These two traits might be useful in indirect selection for yield improvement in the material generated from the three crosses under consideration.

Multi-task Gaussian process for imputing missing data in multi-trait and multi-environment trials.

PubMed

Hori, Tomoaki; Montcho, David; Agbangla, Clement; Ebana, Kaworu; Futakuchi, Koichi; Iwata, Hiroyoshi

2016-11-01

A method based on a multi-task Gaussian process using self-measuring similarity gave increased accuracy for imputing missing phenotypic data in multi-trait and multi-environment trials. Multi-environmental trial (MET) data often encounter the problem of missing data. Accurate imputation of missing data makes subsequent analysis more effective and the results easier to understand. Moreover, accurate imputation may help to reduce the cost of phenotyping for thinned-out lines tested in METs. METs are generally performed for multiple traits that are correlated to each other. Correlation among traits can be useful information for imputation, but single-trait-based methods cannot utilize information shared by traits that are correlated. In this paper, we propose imputation methods based on a multi-task Gaussian process (MTGP) using self-measuring similarity kernels reflecting relationships among traits, genotypes, and environments. This framework allows us to use genetic correlation among multi-trait multi-environment data and also to combine MET data and marker genotype data. We compared the accuracy of three MTGP methods and iterative regularized PCA using rice MET data. Two scenarios for the generation of missing data at various missing rates were considered. The MTGP performed a better imputation accuracy than regularized PCA, especially at high missing rates. Under the 'uniform' scenario, in which missing data arise randomly, inclusion of marker genotype data in the imputation increased the imputation accuracy at high missing rates. Under the 'fiber' scenario, in which missing data arise in all traits for some combinations between genotypes and environments, the inclusion of marker genotype data decreased the imputation accuracy for most traits while increasing the accuracy in a few traits remarkably. The proposed methods will be useful for solving the missing data problem in MET data.

Genes for hereditary sensory and autonomic neuropathies: a genotype-phenotype correlation.

PubMed

Rotthier, Annelies; Baets, Jonathan; De Vriendt, Els; Jacobs, An; Auer-Grumbach, Michaela; Lévy, Nicolas; Bonello-Palot, Nathalie; Kilic, Sara Sebnem; Weis, Joachim; Nascimento, Andrés; Swinkels, Marielle; Kruyt, Moyo C; Jordanova, Albena; De Jonghe, Peter; Timmerman, Vincent

2009-10-01

Hereditary sensory and autonomic neuropathies (HSAN) are clinically and genetically heterogeneous disorders characterized by axonal atrophy and degeneration, exclusively or predominantly affecting the sensory and autonomic neurons. So far, disease-associated mutations have been identified in seven genes: two genes for autosomal dominant (SPTLC1 and RAB7) and five genes for autosomal recessive forms of HSAN (WNK1/HSN2, NTRK1, NGFB, CCT5 and IKBKAP). We performed a systematic mutation screening of the coding sequences of six of these genes on a cohort of 100 familial and isolated patients diagnosed with HSAN. In addition, we screened the functional candidate gene NGFR (p75/NTR) encoding the nerve growth factor receptor. We identified disease-causing mutations in SPTLC1, RAB7, WNK1/HSN2 and NTRK1 in 19 patients, of which three mutations have not previously been reported. The phenotypes associated with mutations in NTRK1 and WNK1/HSN2 typically consisted of congenital insensitivity to pain and anhidrosis, and early-onset ulcero-mutilating sensory neuropathy, respectively. RAB7 mutations were only found in patients with a Charcot-Marie-Tooth type 2B (CMT2B) phenotype, an axonal sensory-motor neuropathy with pronounced ulcero-mutilations. In SPTLC1, we detected a novel mutation (S331F) corresponding to a previously unknown severe and early-onset HSAN phenotype. No mutations were found in NGFB, CCT5 and NGFR. Overall disease-associated mutations were found in 19% of the studied patient group, suggesting that additional genes are associated with HSAN. Our genotype-phenotype correlation study broadens the spectrum of HSAN and provides additional insights for molecular and clinical diagnosis.

A FBN1 mutation association with different phenotypes of Marfan syndrome in a Chinese family.

PubMed

Li, Yapeng; Xu, Jianhua; Chen, Mingjie; Du, Binbin; Li, Qiaoli; Xing, Qinghe; Zhang, Yanzhou

2016-09-01

Previous studies demonstrated that patients with different FBN1 mutations often present more considerable phenotypic variation compared to different members of the related family carrying a same mutation. The purpose of our study was to identify pathogenic mutation and provide more information about genotype-phenotypic correlations in a large Chinese family with Marfan syndrome. 15 related family members from a Chinese 4-generation pedigree with Marfan syndrome underwent physical, ophthalmologic, radiological and cardiovascular examinations. The propositus has De Bakey III aortic dissection and didn't fulfill the revised Ghent criteria for Marfan syndrome. Nine family members have ectopia lentis and their echocardiogram was normal. Five other family members have no evidence of Marfan syndrome. Genomic DNA was isolated from blood leukocytes. The exome sequencing was employed on the propositus, then the Sanger sequencing was conducted for mutation verification in other 14 participants of this family. The causative mutation in FBN1 discovered in the propositus was a known heterozygous missense mutation, c.1633T>G (p.R545C), in exon 14 (NM 000138). This same mutation was also identified in all 9 ectopia lentis patients and one unaffected 8-year-old girl. However, the same mutation was not discovered in other 4 unaffected family members. Our data enhance the information of genotype-phenotype correlation owing to FBN1 mutations. To our current knowledge, we firstly reported that the same FBN1 mutation, c. 1633C>T (Arg545Cys), was detected simultaneously in three different cardinal phenotypes (ectopia lentis, aortic dissection and unaffected) within one family. The unaffected girl with FBN1 mutation may presumably represent a rare case of nonpenetrance. Copyright © 2016 Elsevier B.V. All rights reserved.

Analysis of N- and O-Linked Protein Glycosylation in Children with Prader-Willi Syndrome

ERIC Educational Resources Information Center

Munce, T.; Heussler, H. S.; Bowling, F. G.

2010-01-01

Background: Current genotype-phenotype correlations in Prader-Willi syndrome (PWS) are struggling to give an explanation of the diversity in phenotype and there is a need to move towards a molecular understanding of PWS. A range of functions related to glycoproteins are involved in the pathophysiology of PWS and it may be that abnormal…

Trait variation and genetic diversity in a banana genomic selection training population

PubMed Central

Nyine, Moses; Uwimana, Brigitte; Swennen, Rony; Batte, Michael; Brown, Allan; Christelová, Pavla; Hřibová, Eva; Lorenzen, Jim

2017-01-01

Banana (Musa spp.) is an important crop in the African Great Lakes region in terms of income and food security, with the highest per capita consumption worldwide. Pests, diseases and climate change hamper sustainable production of bananas. New breeding tools with increased crossbreeding efficiency are being investigated to breed for resistant, high yielding hybrids of East African Highland banana (EAHB). These include genomic selection (GS), which will benefit breeding through increased genetic gain per unit time. Understanding trait variation and the correlation among economically important traits is an essential first step in the development and selection of suitable GS models for banana. In this study, we tested the hypothesis that trait variations in bananas are not affected by cross combination, cycle, field management and their interaction with genotype. A training population created using EAHB breeding material and its progeny was phenotyped in two contrasting conditions. A high level of correlation among vegetative and yield related traits was observed. Therefore, genomic selection models could be developed for traits that are easily measured. It is likely that the predictive ability of traits that are difficult to phenotype will be similar to less difficult traits they are highly correlated with. Genotype response to cycle and field management practices varied greatly with respect to traits. Yield related traits accounted for 31–35% of principal component variation under low and high input field management conditions. Resistance to Black Sigatoka was stable across cycles but varied under different field management depending on the genotype. The best cross combination was 1201K-1xSH3217 based on selection response (R) of hybrids. Genotyping using simple sequence repeat (SSR) markers revealed that the training population was genetically diverse, reflecting a complex pedigree background, which was mostly influenced by the male parents. PMID:28586365

Trait variation and genetic diversity in a banana genomic selection training population.

PubMed

Nyine, Moses; Uwimana, Brigitte; Swennen, Rony; Batte, Michael; Brown, Allan; Christelová, Pavla; Hřibová, Eva; Lorenzen, Jim; Doležel, Jaroslav

2017-01-01

Banana (Musa spp.) is an important crop in the African Great Lakes region in terms of income and food security, with the highest per capita consumption worldwide. Pests, diseases and climate change hamper sustainable production of bananas. New breeding tools with increased crossbreeding efficiency are being investigated to breed for resistant, high yielding hybrids of East African Highland banana (EAHB). These include genomic selection (GS), which will benefit breeding through increased genetic gain per unit time. Understanding trait variation and the correlation among economically important traits is an essential first step in the development and selection of suitable GS models for banana. In this study, we tested the hypothesis that trait variations in bananas are not affected by cross combination, cycle, field management and their interaction with genotype. A training population created using EAHB breeding material and its progeny was phenotyped in two contrasting conditions. A high level of correlation among vegetative and yield related traits was observed. Therefore, genomic selection models could be developed for traits that are easily measured. It is likely that the predictive ability of traits that are difficult to phenotype will be similar to less difficult traits they are highly correlated with. Genotype response to cycle and field management practices varied greatly with respect to traits. Yield related traits accounted for 31-35% of principal component variation under low and high input field management conditions. Resistance to Black Sigatoka was stable across cycles but varied under different field management depending on the genotype. The best cross combination was 1201K-1xSH3217 based on selection response (R) of hybrids. Genotyping using simple sequence repeat (SSR) markers revealed that the training population was genetically diverse, reflecting a complex pedigree background, which was mostly influenced by the male parents.

Novel TMEM67 Mutations and Genotype-phenotype Correlates in Meckelin-related Ciliopathies

PubMed Central

Iannicelli, Miriam; Brancati, Francesco; Mougou-Zerelli, Soumaya; Mazzotta, Annalisa; Thomas, Sophie; Elkhartoufi, Nadia; Travaglini, Lorena; Gomes, Céline; Ardissino, Gian Luigi; Bertini, Enrico; Boltshauser, Eugen; Castorina, Pierangela; D'Arrigo, Stefano; Fischetto, Rita; Leroy, Brigitte; Loget, Philippe; Bonnière, Maryse; Starck, Lena; Tantau, Julia; Gentilin, Barbara; Majore, Silvia; Swistun, Dominika; Flori, Elizabeth; Lalatta, Faustina; Pantaleoni, Chiara; Johannes.Penzien; Grammatico, Paola; Dallapiccola, Bruno; Gleeson, Joseph G.; Attie-Bitach, Tania; Valente, Enza Maria

2010-01-01

Human ciliopathies are hereditary conditions caused by defects of proteins expressed at the primary cilium. Among ciliopathies, Joubert syndrome and related disorders (JSRD), Meckel syndrome (MKS) and nephronophthisis (NPH) present clinical and genetic overlap, being allelic at several loci. One of the most interesting gene is TMEM67, encoding the transmembrane protein meckelin. We performed mutation analysis of TMEM67 in 341 probands, including 265 JSRD representative of all clinical subgroups and 76 MKS fetuses. We identified 33 distinct mutations, of which 20 were novel, in 8/10 (80%) JS with liver involvement (COACH phenotype) and 12/76 (16%) MKS fetuses. No mutations were found in other JSRD subtypes, confirming the strong association between TMEM67 mutations and liver involvement. Literature review of all published TMEM67 mutated cases was performed to delineate genotype-phenotype correlates. In particular, comparison of the types of mutations and their distribution along the gene in lethal versus non lethal phenotypes showed in MKS patients a significant enrichment of missense mutations falling in TMEM67 exons 8 to 15, especially when in combination with a truncating mutation. These exons encode for a region of unknown function in the extracellular domain of meckelin. PMID:20232449

Cardio-facio-cutaneous syndrome: does genotype predict phenotype?

PubMed

Allanson, Judith E; Annerén, Göran; Aoki, Yoki; Armour, Christine M; Bondeson, Marie-Louise; Cave, Helene; Gripp, Karen W; Kerr, Bronwyn; Nystrom, Anna-Maja; Sol-Church, Katia; Verloes, Alain; Zenker, Martin

2011-05-15

Cardio-facio-cutaneous (CFC) syndrome is a sporadic multiple congenital anomalies/mental retardation condition principally caused by mutations in BRAF, MEK1, and MEK2. Mutations in KRAS and SHOC2 lead to a phenotype with overlapping features. In approximately 10–30% of individuals with a clinical diagnosis of CFC, a mutation in one of these causative genes is not found. Cardinal features of CFC include congenital heart defects, a characteristic facial appearance, and ectodermal abnormalities. Additional features include failure to thrive with severe feeding problems, moderate to severe intellectual disability and short stature with relative macrocephaly. First described in 1986, more than 100 affected individuals are reported. Following the discovery of the causative genes, more information has emerged on the breadth of clinical features. Little, however, has been published on genotype–phenotype correlations. This clinical study of 186 children and young adults with mutation-proven CFC syndrome is the largest reported to date. BRAF mutations are documented in 140 individuals (approximately 75%), while 46 (approximately 25%) have a mutation in MEK 1 or MEK 2. The age range is 6 months to 32 years, the oldest individual being a female from the original report [Reynolds et al. (1986); Am J Med Genet 25:413–427]. While some clinical data on 136 are in the literature, 50 are not previously published. We provide new details of the breadth of phenotype and discuss the frequency of particular features in each genotypic group. Pulmonary stenosis is the only anomaly that demonstrates a statistically significant genotype–phenotype correlation, being more common in individuals with a BRAF mutation.

Minimum number of measurements for evaluating Bertholletia excelsa.

PubMed

Baldoni, A B; Tonini, H; Tardin, F D; Botelho, S C C; Teodoro, P E

2017-09-27

Repeatability studies on fruit species are of great importance to identify the minimum number of measurements necessary to accurately select superior genotypes. This study aimed to identify the most efficient method to estimate the repeatability coefficient (r) and predict the minimum number of measurements needed for a more accurate evaluation of Brazil nut tree (Bertholletia excelsa) genotypes based on fruit yield. For this, we assessed the number of fruits and dry mass of seeds of 75 Brazil nut genotypes, from native forest, located in the municipality of Itaúba, MT, for 5 years. To better estimate r, four procedures were used: analysis of variance (ANOVA), principal component analysis based on the correlation matrix (CPCOR), principal component analysis based on the phenotypic variance and covariance matrix (CPCOV), and structural analysis based on the correlation matrix (mean r - AECOR). There was a significant effect of genotypes and measurements, which reveals the need to study the minimum number of measurements for selecting superior Brazil nut genotypes for a production increase. Estimates of r by ANOVA were lower than those observed with the principal component methodology and close to AECOR. The CPCOV methodology provided the highest estimate of r, which resulted in a lower number of measurements needed to identify superior Brazil nut genotypes for the number of fruits and dry mass of seeds. Based on this methodology, three measurements are necessary to predict the true value of the Brazil nut genotypes with a minimum accuracy of 85%.

Multivariate Analysis of Genotype-Phenotype Association.

PubMed

Mitteroecker, Philipp; Cheverud, James M; Pavlicev, Mihaela

2016-04-01

With the advent of modern imaging and measurement technology, complex phenotypes are increasingly represented by large numbers of measurements, which may not bear biological meaning one by one. For such multivariate phenotypes, studying the pairwise associations between all measurements and all alleles is highly inefficient and prevents insight into the genetic pattern underlying the observed phenotypes. We present a new method for identifying patterns of allelic variation (genetic latent variables) that are maximally associated-in terms of effect size-with patterns of phenotypic variation (phenotypic latent variables). This multivariate genotype-phenotype mapping (MGP) separates phenotypic features under strong genetic control from less genetically determined features and thus permits an analysis of the multivariate structure of genotype-phenotype association, including its dimensionality and the clustering of genetic and phenotypic variables within this association. Different variants of MGP maximize different measures of genotype-phenotype association: genetic effect, genetic variance, or heritability. In an application to a mouse sample, scored for 353 SNPs and 11 phenotypic traits, the first dimension of genetic and phenotypic latent variables accounted for >70% of genetic variation present in all 11 measurements; 43% of variation in this phenotypic pattern was explained by the corresponding genetic latent variable. The first three dimensions together sufficed to account for almost 90% of genetic variation in the measurements and for all the interpretable genotype-phenotype association. Each dimension can be tested as a whole against the hypothesis of no association, thereby reducing the number of statistical tests from 7766 to 3-the maximal number of meaningful independent tests. Important alleles can be selected based on their effect size (additive or nonadditive effect on the phenotypic latent variable). This low dimensionality of the genotype-phenotype map has important consequences for gene identification and may shed light on the evolvability of organisms. Copyright © 2016 by the Genetics Society of America.

Phenotype, biochemical features, genotype and treatment outcome of pyridoxine-dependent epilepsy.

PubMed

Al Teneiji, Amal; Bruun, Theodora U J; Cordeiro, Dawn; Patel, Jaina; Inbar-Feigenberg, Michal; Weiss, Shelly; Struys, Eduard; Mercimek-Mahmutoglu, Saadet

2017-04-01

We report treatment outcome of eleven patients with pyridoxine-dependent epilepsy caused by pathogenic variants in ALDH7A1 (PDE-ALDH7A1). We developed a clinical severity score to compare phenotype with biochemical features, genotype and delays in the initiation of pyridoxine. Clinical severity score included 1) global developmental delay/ intellectual disability; 2) age of seizure onset prior to pyridoxine; 3) current seizures on treatment. Phenotype scored 1-3 = mild; 4-6 = moderate; and 7-9 = severe. Five patients had mild, four patients had moderate, and two patients had severe phenotype. Phenotype ranged from mild to severe in eight patients (no lysine-restricted diet in the infantile period) with more than 10-fold elevated urine or plasma α-AASA levels. Phenotype ranged from mild to moderate in patients with homozygous truncating variants and from moderate to severe in patients with homozygous missense variants. There was no correlation between severity of the phenotype and the degree of α-AASA elevation in urine or genotype. All patients were on pyridoxine, nine patients were on arginine and five patients were on the lysine-restricted diet. 73% of the patients became seizure free on pyridoxine. 25% of the patients had a mild phenotype on pyridoxine monotherapy. Whereas, 100% of the patients, on the lysine-restricted diet initiated within their first 7 months of life, had a mild phenotype. Early initiation of lysine-restricted diet and/or arginine therapy likely improved neurodevelopmental outcome in young patients with PDE-ALDH7A1.

Development and evaluation of a phenotypic assay monitoring resistance formation to protease inhibitors in HIV-1-infected patients.

PubMed

Gehringer, Heike; Von der Helm, Klaus; Seelmeir, Sigrid; Weissbrich, Benedikt; Eberle, Josef; Nitschko, Hans

2003-05-01

A novel phenotypic assay, based on recombinant expression of the HIV-1-protease was developed and evaluated; it monitors the formation of resistance to protease inhibitors. The HIV-1 protease-encoding region from the blood sample of patients was amplified, ligated into the expression vector pBD2, and recombinantly expressed in Escherichia coli TG1 cells. The resulting recombinant enzyme was purified by a newly developed one-step acid extraction protocol. The protease activity was determined in presence of five selected HIV protease inhibitors and the 50% inhibitory concentration (IC(50)) to the respective protease inhibitors determined. The degree of resistance was expressed in terms of x-fold increase in IC(50) compared to the IC(50) value of an HIV-1 wild type protease preparation. The established test system showed a reproducible recombinant expression of each individual patients' HIV-1 protease population. Samples of nine clinically well characterised HIV-1-infected patients with varying degrees of resistance were analysed. There was a good correlation between clinical parameters and the results obtained by this phenotypic assay. For the majority of patients a blind genotypic analysis of the patients' protease domain revealed a fair correlation to the results of the phenotypic assay. In a minority of patients our phenotypic results diverged from the genotypic ones. This novel phenotypic assay can be carried out within 8-10 days, and offers a significant advantage in time to the current employed phenotypic tests.

Highly Discriminatory Variable-Number Tandem-Repeat Markers for Genotyping of Trichophyton interdigitale Strains

PubMed Central

Drira, Ines; Hadrich, Ines; Neji, Sourour; Mahfouth, Nedia; Trabelsi, Houaida; Sellami, Hayet; Makni, Fattouma

2014-01-01

Trichophyton interdigitale is the second most frequent cause of superficial fungal infections of various parts of the human body. Studying the population structure and genotype differentiation of T. interdigitale strains may lead to significant improvements in clinical practice. The present study aimed to develop and select suitable variable-number tandem-repeat (VNTR) markers for 92 clinical strains of T. interdigitale. On the basis of an analysis of four VNTR markers, four to eight distinct alleles were detected for each marker. The marker with the highest discriminatory power had eight alleles and a D value of 0.802. The combination of all four markers yielded a D value of 0.969 with 29 distinct multilocus genotypes. VNTR typing revealed the genetic diversity of the strains, identifying three populations according to their colonization sites. A correlation between phenotypic characteristics and multilocus genotypes was observed. Seven patients harbored T. interdigitale strains with different genotypes. Typing of clinical T. interdigitale samples by VNTR markers displayed excellent discriminatory power and 100% reproducibility. PMID:24989614

Molecular etiology and genotype-phenotype correlation of Chinese Han deaf patients with type I and type II Waardenburg Syndrome.

PubMed

Sun, Lianhua; Li, Xiaohua; Shi, Jun; Pang, Xiuhong; Hu, Yechen; Wang, Xiaowen; Wu, Hao; Yang, Tao

2016-10-19

Waardenburg syndrome (WS) characterized by sensorineural hearing loss and pigmentary abnormalities is genetically heterogeneous and phenotypically variable. This study investigated the molecular etiology and genotype-phenotype correlation of WS in 36 Chinese Han deaf probands and 16 additional family members that were clinically diagnosed with WS type I (WS1, n = 8) and type II (WS2, n = 42). Mutation screening of six WS-associated genes detected PAX3 mutations in 6 (86%) of the 7 WS1 probands. Among the 29 WS2 probands, 13 (45%) and 10 (34%) were identified with SOX10 and MITF mutations, respectively. Nineteen of the 26 detected mutations were novel. In WS2 probands whose parental DNA samples were available, de novo mutations were frequently seen for SOX10 mutations (7/8) but not for MITF mutations (0/5, P = 0.005). Excessive freckle, a common feature of WS2 in Chinese Hans, was frequent in WS2 probands with MITF mutations (7/10) but not in those with SOX10 mutations (0/13, P = 4.9 × 10 -4 ). Our results showed that mutations in SOX10 and MITF are two major causes for deafness associated with WS2. These two subtypes of WS2 can be distinguished by the high de novo rate of the SOX10 mutations and the excessive freckle phenotype exclusively associated with the MITF mutations.

Molecular etiology and genotype-phenotype correlation of Chinese Han deaf patients with type I and type II Waardenburg Syndrome

PubMed Central

Sun, Lianhua; Li, Xiaohua; Shi, Jun; Pang, Xiuhong; Hu, Yechen; Wang, Xiaowen; Wu, Hao; Yang, Tao

2016-01-01

Waardenburg syndrome (WS) characterized by sensorineural hearing loss and pigmentary abnormalities is genetically heterogeneous and phenotypically variable. This study investigated the molecular etiology and genotype-phenotype correlation of WS in 36 Chinese Han deaf probands and 16 additional family members that were clinically diagnosed with WS type I (WS1, n = 8) and type II (WS2, n = 42). Mutation screening of six WS-associated genes detected PAX3 mutations in 6 (86%) of the 7 WS1 probands. Among the 29 WS2 probands, 13 (45%) and 10 (34%) were identified with SOX10 and MITF mutations, respectively. Nineteen of the 26 detected mutations were novel. In WS2 probands whose parental DNA samples were available, de novo mutations were frequently seen for SOX10 mutations (7/8) but not for MITF mutations (0/5, P = 0.005). Excessive freckle, a common feature of WS2 in Chinese Hans, was frequent in WS2 probands with MITF mutations (7/10) but not in those with SOX10 mutations (0/13, P = 4.9 × 10−4). Our results showed that mutations in SOX10 and MITF are two major causes for deafness associated with WS2. These two subtypes of WS2 can be distinguished by the high de novo rate of the SOX10 mutations and the excessive freckle phenotype exclusively associated with the MITF mutations. PMID:27759048

Gravimetric phenotyping of whole plant transpiration responses to atmospheric vapour pressure deficit identifies genotypic variation in water use efficiency.

PubMed

Ryan, Annette C; Dodd, Ian C; Rothwell, Shane A; Jones, Ros; Tardieu, Francois; Draye, Xavier; Davies, William J

2016-10-01

There is increasing interest in rapidly identifying genotypes with improved water use efficiency, exemplified by the development of whole plant phenotyping platforms that automatically measure plant growth and water use. Transpirational responses to atmospheric vapour pressure deficit (VPD) and whole plant water use efficiency (WUE, defined as the accumulation of above ground biomass per unit of water used) were measured in 100 maize (Zea mays L.) genotypes. Using a glasshouse based phenotyping platform with naturally varying VPD (1.5-3.8kPa), a 2-fold variation in WUE was identified in well-watered plants. Regression analysis of transpiration versus VPD under these conditions, and subsequent whole plant gas exchange at imposed VPDs (0.8-3.4kPa) showed identical responses in specific genotypes. Genotype response of transpiration versus VPD fell into two categories: 1) a linear increase in transpiration rate with VPD with low (high WUE) or high (low WUE) transpiration rate at all VPDs, 2) a non-linear response with a pronounced change point at low VPD (high WUE) or high VPD (low WUE). In the latter group, high WUE genotypes required a significantly lower VPD before transpiration was restricted, and had a significantly lower rate of transpiration in response to VPD after this point, when compared to low WUE genotypes. Change point values were significantly positively correlated with stomatal sensitivity to VPD. A change point in stomatal response to VPD may explain why some genotypes show contradictory WUE rankings according to whether they are measured under glasshouse or field conditions. Furthermore, this novel use of a high throughput phenotyping platform successfully reproduced the gas exchange responses of individuals measured in whole plant chambers, accelerating the identification of plants with high WUE. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genotypic Variation in Nitrogen Utilization Efficiency of Oilseed Rape (Brassica napus) Under Contrasting N Supply in Pot and Field Experiments

PubMed Central

He, Huiying; Yang, Rui; Li, Yajun; Ma, Aisheng; Cao, Lanqin; Wu, Xiaoming; Chen, Biyun; Tian, Hui; Gao, Yajun

2017-01-01

Oilseed rape (Brassica napus) characteristically has high N uptake efficiency and low N utilization efficiency (NUtE, seed yield/shoot N accumulation). Determining the NUtE phenotype of various genotypes in different growth conditions is a way of finding target traits to improve oilseed rape NUtE. The aim of this study was to compare oilseed rape genotypes grown on contrasting N supply rates in pot and field experiments to investigate the genotypic variations of NUtE and to identify indicators of N efficient genotypes. For 50 oilseed rape genotypes, NUtE, dry matter and N partitioning, morphological characteristics, and the yield components were investigated under high and low N supplies in a greenhouse pot experiment and a field trial. Although the genotype rankings of NUtE were different between the pot experiment and the field trial, some genotypes performed consistently in both two environments. N-responder, N-nonresponder, N-efficient and N-inefficient genotypes were identified from these genotypes with consistent NUtE. The correlations between the pot experiment and the field trial in NUtE were only 0.34 at high N supplies and no significant correlations were found at low N supplies. However, Pearson coefficient correlation (r) and principal component analysis showed NUtE had similar genetic correlations with other traits across the pot and field experiment. Among the yield components, only seeds per silique showed strong and positive correlations with NUtE under varying N supply in both experiments (r = 0.47**; 0.49**; 0.47**; 0.54**). At high and low N supply, NUtE was positively correlated with seed yield (r = 0.45**; 0.53**; 0.39**; 0.87**), nitrogen harvest index (NHI, r = 0.68**; 0.82**; 0.99**; 0.89**), and harvest index (HI, r = 0.79**; 0.83**; 0.90**; 0.78**) and negatively correlated with biomass distribution to stem and leaf (r = −0.34**; −0.45**; −0.37**; 0.62**), all aboveground plant section N concentration (r from −0.30* to −0.80**), N distribution to the vegetative parts (silique husk, stem and leaf) (r from −0.40** to −0.83**). N-efficient (N-responder) genotypes produced more seeds per silique and had significantly higher NHI and HI than did N-inefficient (N-nonresponder) genotypes. In conclusion, across the pot and field experiments, the 50 genotypes had similar underlying traits correlated with NUtE and seeds per silique may be a good indicator of NUtE. PMID:29163565

Electrocardiographic Characterization of Cardiac Hypertrophy in Mice that Overexpress the ErbB2 Receptor Tyrosine Kinase

PubMed Central

Sysa-Shah, Polina; Sørensen, Lars L; Abraham, M Roselle; Gabrielson, Kathleen L

2015-01-01

Electrocardiography is an important method for evaluation and risk stratification of patients with cardiac hypertrophy. We hypothesized that the recently developed transgenic mouse model of cardiac hypertrophy (ErbB2tg) will display distinct ECG features, enabling WT (wild type) mice to be distinguished from transgenic mice without using conventional PCR genotyping. We evaluated more than 2000 mice and developed specific criteria for genotype determination by using cageside ECG, during which unanesthetized mice were manually restrained for less than 1 min. Compared with those from WT counterparts, the ECG recordings of ErbB2tg mice were characterized by higher P- and R-wave amplitudes, broader QRS complexes, inverted T waves, and ST interval depression. Pearson's correlation matrix analysis of combined WT and ErbB2tg data revealed significant correlation between heart weight and the ECG parameters of QT interval (corrected for heart rate), QRS interval, ST height, R amplitude, P amplitude, and PR interval. In addition, the left ventricular posterior wall thickness as determined by echocardiography correlated with ECG-determined ST height, R amplitude, QRS interval; echocardiographic left ventricular mass correlated with ECG-determined ST height and PR interval. In summary, we have determined phenotypic ECG criteria to differentiate ErbB2tg from WT genotypes in 98.8% of mice. This inexpensive and time-efficient ECG-based phenotypic method might be applied to differentiate between genotypes in other rodent models of cardiac hypertrophy. Furthermore, with appropriate modifications, this method might be translated for use in other species. PMID:26310459

Breeding value prediction for production traits in layer chickens using pedigree or genomic relationships in a reduced animal model.

PubMed

Wolc, Anna; Stricker, Chris; Arango, Jesus; Settar, Petek; Fulton, Janet E; O'Sullivan, Neil P; Preisinger, Rudolf; Habier, David; Fernando, Rohan; Garrick, Dorian J; Lamont, Susan J; Dekkers, Jack C M

2011-01-21

Genomic selection involves breeding value estimation of selection candidates based on high-density SNP genotypes. To quantify the potential benefit of genomic selection, accuracies of estimated breeding values (EBV) obtained with different methods using pedigree or high-density SNP genotypes were evaluated and compared in a commercial layer chicken breeding line. The following traits were analyzed: egg production, egg weight, egg color, shell strength, age at sexual maturity, body weight, albumen height, and yolk weight. Predictions appropriate for early or late selection were compared. A total of 2,708 birds were genotyped for 23,356 segregating SNP, including 1,563 females with records. Phenotypes on relatives without genotypes were incorporated in the analysis (in total 13,049 production records).The data were analyzed with a Reduced Animal Model using a relationship matrix based on pedigree data or on marker genotypes and with a Bayesian method using model averaging. Using a validation set that consisted of individuals from the generation following training, these methods were compared by correlating EBV with phenotypes corrected for fixed effects, selecting the top 30 individuals based on EBV and evaluating their mean phenotype, and by regressing phenotypes on EBV. Using high-density SNP genotypes increased accuracies of EBV up to two-fold for selection at an early age and by up to 88% for selection at a later age. Accuracy increases at an early age can be mostly attributed to improved estimates of parental EBV for shell quality and egg production, while for other egg quality traits it is mostly due to improved estimates of Mendelian sampling effects. A relatively small number of markers was sufficient to explain most of the genetic variation for egg weight and body weight.

Phenotype- and Genotype-Specific Structural Alterations in Spasmodic Dysphonia

PubMed Central

Bianchi, Serena; Battistella, Giovanni; Huddleston, Hailey; Scharf, Rebecca; Fleysher, Lazar; Rumbach, Anna F.; Frucht, Steven J.; Blitzer, Andrew; Ozelius, Laurie J.; Simonyan, Kristina

2017-01-01

Background Spasmodic dysphonia is a focal dystonia characterized by involuntary spasms in the laryngeal muscles that occur selectively during speaking. Although hereditary trends have been reported in up to 16% of patients, the causative etiology of spasmodic dysphonia is unclear, and the influences of various phenotypes and genotypes on disorder pathophysiology are poorly understood. In this study, we examined structural alterations in cortical gray matter and white matter integrity in relationship to different phenotypes and putative genotypes of spasmodic dysphonia to elucidate the structural component of its complex pathophysiology. Methods Eighty-nine patients with spasmodic dysphonia underwent high-resolution magnetic resonance imaging and diffusion-weighted imaging to examine cortical thickness and white matter fractional anisotropy in adductor versus abductor forms (distinct phenotypes) and in sporadic versus familial cases (distinct genotypes). Results Phenotype-specific abnormalities were localized in the left sensorimotor cortex and angular gyrus and the white matter bundle of the right superior corona radiata. Genotype-specific alterations were found in the left superior temporal gyrus, supplementary motor area, and the arcuate portion of the left superior longitudinal fasciculus. Conclusions Our findings suggest that phenotypic differences in spasmodic dysphonia arise at the level of the primary and associative areas of motor control, whereas genotype-related pathophysiological mechanisms may be associated with dysfunction of regions regulating phonological and sensory processing. Identification of structural alterations specific to disorder phenotype and putative genotype provides an important step toward future delineation of imaging markers and potential targets for novel therapeutic interventions for spasmodic dysphonia. PMID:28186656

Phenotypic and genotypic analysis of clarithromycin-resistant Helicobacter pylori from Bogotá D.C., Colombia.

PubMed

Trespalacios, Alba A; Otero, William; Caminos, Jorge E; Mercado, Marcela M; Avila, Jenny; Rosero, Liliana E; Arévalo, Azucena; Poutou-Piñales, Raúl A; Graham, David Y

2013-08-01

Resistance of Helicobacter pylori to clarithromycin is the most common cause of treatment failure in patients with H. pylori infections. This study describes the MICs and the presence of 23S rRNA mutations of H. pylori isolates from Bogotá, D.C., Colombia. H. pylori were isolated from gastric biopsies from patients with functional dyspepsia. Clarithromycin susceptibility was investigated by agar dilution and strains were considered resistant if the MIC was ≥ 1 μg/ml. DNA sequences of the 23S rRNA gene of strains resistant and sensitive to clarithromycin were determined to identify specific point mutations. Clarithromycin resistance was present in 13.6% of patients by agar dilution. The A2143G, A2142G and A2142C mutations were found in 90.5, 7.1, and 2.4% of H. pylori strains with resistance genotype.The resistant phenotype was associated with 23S rRNA resistance genotype in 85.7% of isolates. The point mutations in 23S rRNA were well correlated with MICs values for clarithromycin.

Clustering high-dimensional mixed data to uncover sub-phenotypes: joint analysis of phenotypic and genotypic data.

PubMed

McParland, D; Phillips, C M; Brennan, L; Roche, H M; Gormley, I C

2017-12-10

The LIPGENE-SU.VI.MAX study, like many others, recorded high-dimensional continuous phenotypic data and categorical genotypic data. LIPGENE-SU.VI.MAX focuses on the need to account for both phenotypic and genetic factors when studying the metabolic syndrome (MetS), a complex disorder that can lead to higher risk of type 2 diabetes and cardiovascular disease. Interest lies in clustering the LIPGENE-SU.VI.MAX participants into homogeneous groups or sub-phenotypes, by jointly considering their phenotypic and genotypic data, and in determining which variables are discriminatory. A novel latent variable model that elegantly accommodates high dimensional, mixed data is developed to cluster LIPGENE-SU.VI.MAX participants using a Bayesian finite mixture model. A computationally efficient variable selection algorithm is incorporated, estimation is via a Gibbs sampling algorithm and an approximate BIC-MCMC criterion is developed to select the optimal model. Two clusters or sub-phenotypes ('healthy' and 'at risk') are uncovered. A small subset of variables is deemed discriminatory, which notably includes phenotypic and genotypic variables, highlighting the need to jointly consider both factors. Further, 7 years after the LIPGENE-SU.VI.MAX data were collected, participants underwent further analysis to diagnose presence or absence of the MetS. The two uncovered sub-phenotypes strongly correspond to the 7-year follow-up disease classification, highlighting the role of phenotypic and genotypic factors in the MetS and emphasising the potential utility of the clustering approach in early screening. Additionally, the ability of the proposed approach to define the uncertainty in sub-phenotype membership at the participant level is synonymous with the concepts of precision medicine and nutrition. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Phenotype-genotype correlations in congenital isolated growth hormone deficiency (IGHD).

PubMed

Alatzoglou, Kyriaki S; Dattani, Mehul T

2012-01-01

Isolated growth hormone deficiency (IGHD) may be congenital, often due to genetic mutations, or acquired as a result of other factors such as cranial irradiation. The commonest genes implicated in its genetic etiology are those encoding growth hormone (GH1) and the receptor for GH-releasing hormone (GHRHR). Rarely, IGHD may be caused by mutations in transcription factors (HESX1, SOX3, OTX2) or be the first presentation before the development of other pituitary hormone deficiencies. IGHD has been classified in four genetic forms (type IA, IB, II and III). Despite the increasing number of genes implicated in the etiology of IGHD, mutations in known genes account only for a small percentage of cases; therefore, other as yet unidentified factors may be implicated in its etiology. Although there is no strict genotype/phenotype correlation in patients with IGHD, there are some emerging patterns that may guide us towards a genetic diagnosis of the condition. There is increasing understanding that the phenotype of patients with IGHD is highly variable and sometimes even evolving, dictating the need for long term follow-up in these cases.

Beyond mean allelic effects: A locus at the major color gene MC1R associates also with differing levels of phenotypic and genetic (co)variance for coloration in barn owls.

PubMed

San-Jose, Luis M; Ducret, Valérie; Ducrest, Anne-Lyse; Simon, Céline; Roulin, Alexandre

2017-10-01

The mean phenotypic effects of a discovered variant help to predict major aspects of the evolution and inheritance of a phenotype. However, differences in the phenotypic variance associated to distinct genotypes are often overlooked despite being suggestive of processes that largely influence phenotypic evolution, such as interactions between the genotypes with the environment or the genetic background. We present empirical evidence for a mutation at the melanocortin-1-receptor gene, a major vertebrate coloration gene, affecting phenotypic variance in the barn owl, Tyto alba. The white MC1R allele, which associates with whiter plumage coloration, also associates with a pronounced phenotypic and additive genetic variance for distinct color traits. Contrarily, the rufous allele, associated with a rufous coloration, relates to a lower phenotypic and additive genetic variance, suggesting that this allele may be epistatic over other color loci. Variance differences between genotypes entailed differences in the strength of phenotypic and genetic associations between color traits, suggesting that differences in variance also alter the level of integration between traits. This study highlights that addressing variance differences of genotypes in wild populations provides interesting new insights into the evolutionary mechanisms and the genetic architecture underlying the phenotype. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

[Prader Willi syndrome patients: study of 77 patients].

PubMed

Poyatos, David; Camprubí, Cristina; Gabau, Elisabeth; Nosas, Ramón; Villatoro, Sergi; Coll, María Dolores; Guitart, Miriam

2009-11-07

The Prader-Willi syndrome (PWS) is a disease of genetic origin. It is characterized by neonatal hypotonia, hypogonadism, hiperfagia leading to obesity, low stature, developmental delay, moderate mental retardation, abnormal behavior and characteristic facial appearance. It is caused by the loss or the inactivation of paternal genes of the imprinted region 15q11-13. There are different genetic causes: paternal 15q11-q13 deletion in 70% of patients, maternal uniparental disomy in the 20-25% and less than 5% have an imprinting defect. We present the results obtained in the transverse clinical - genetic study of 77 PWS patients. There has been realized the study of 374 suspected PWS patients. Cytogenetics studies of bands G and hybridization in situ fluorescent (FISH) and molecular genetics analysis of microsatellites, Southern blot, MS-PCR and sequenciation were carried out. Holm's criteria use for the correlation phenotype - genotype in 48 patients. PWS was confirmed in 77 patients, 46 deletion, 16 uniparental disomy, two imprinting defect and 13 only PWS methylation pattern. Significant differences do not observe in the correlation phenotype - genotype. The frequencies of the molecular alterations, 71.87 % deletion, 25 % UPD and 3.12 % DI, they are similar to described in the literature. It presents the algorithm of diagnosis used with the MS-PCR as rapid technology to confirm PWS.

A boy with partial dup(18q)/del(18p) due to a maternal pericentric inversion: Genotype-phenotype correlation and risk of recombinant chromosomes based on systematic review of the literature.

PubMed

Lustosa-Mendes, Elaine; Dos Santos, Ana Paula; Viguetti-Campos, Nilma Lúcia; Vieira, Társis Paiva; Gil-da-Silva-Lopes, Vera Lúcia

2017-01-01

We report a boy carrying a recombinant chromosome 18, with terminal deletion of 10.8 Mb from 18p11.32 to 18p11.21 and a terminal duplication of 22.8 Mb from 18q21.31 to 18q23, resulting from a maternal pericentric inversion of the chromosome 18. He presented with poor growth, developmental delay, facial dysmorphisms, surgically repaired left cleft lip and palate, a mild form of holoprosencephaly characterized by single central incisor and agenesis of the septum pellucidum, and body asymmetry. Based on the systematic review of the literature, we discuss genotype-phenotype correlation and the risk for the recombinants of pericentric inversions of chromosome 18. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Neutral Lipid Storage Diseases: clinical/genetic features and natural history in a large cohort of Italian patients.

PubMed

Pennisi, Elena Maria; Arca, Marcello; Bertini, Enrico; Bruno, Claudio; Cassandrini, Denise; D'amico, Adele; Garibaldi, Matteo; Gragnani, Francesca; Maggi, Lorenzo; Massa, Roberto; Missaglia, Sara; Morandi, Lucia; Musumeci, Olimpia; Pegoraro, Elena; Rastelli, Emanuele; Santorelli, Filippo Maria; Tasca, Elisabetta; Tavian, Daniela; Toscano, Antonio; Angelini, Corrado

2017-05-12

A small number of patients affected by Neutral Lipid Storage Diseases (NLSDs: NLSD type M with Myopathy and NLSD type I with Ichthyosis) have been described in various ethnic groups worldwide. However, relatively little is known about the progression and phenotypic variability of the disease in large specific populations. The aim of our study was to assess the natural history, disability and genotype-phenotype correlations in Italian patients with NLSDs. Twenty-one patients who satisfied the criteria for NLSDs were enrolled in a retrospective cross-sectional study to evaluate the genetic aspects, clinical signs at onset, disability progression and comorbidities associated with this group of diseases. During the clinical follow-up (range: 2-44 years, median: 17.8 years), two patients (9.5%, both with NLSD-I) died of hepatic failure, and a further five (24%) lost their ability to walk or needed help when walking after a mean period of 30.6 years of disease. None of the patients required mechanical ventilation. No patient required a heart transplant, one patient with NLSD-M was implanted with a cardioverter defibrillator for severe arrhythmias. The genotype/phenotype correlation analysis in our population showed that the same gene mutations were associated with a varying clinical onset and course. This study highlights peculiar aspects of Italian NLSD patients that differ from those observed in Japanese patients, who were found to be affected by a marked hypertrophic cardiopathy. Owing to the varying phenotypic expression of the same mutations, it is conceivable that some additional genetic or epigenetic factors affect the symptoms and progression in this group of diseases.

Identification of sorghum hybrids with high phenotypic stability using GGE biplot methodology.

PubMed

Teodoro, P E; Almeida Filho, J E; Daher, R F; Menezes, C B; Cardoso, M J; Godinho, V P C; Torres, F E; Tardin, F D

2016-06-10

The aim of this study was to identify sorghum hybrids that have both high yield and phenotypic stability in Brazilian environments. Seven trials were conducted between February and March 2011. The experimental design was a randomized complete block with 25 treatments and three replicates. The treatments consisted of 20 simple pre-commercial hybrids and five witnesses of grain sorghum. Sorghum genotypes were analyzed by the genotype main effects + genotype environment interaction (GGE) biplot method if significant genotype x environment interaction, adaptability, and phenotypic stability were detected. GGE biplot methodology identified two groups of environments, the first composed of Água Comprida-MG, Montividiu-GO, and Vilhena- RO and the second of Guaíra-SP and Sete Lagoas-MG. The BRS 308 and 1G282 genotypes were found to have high grain yield, adaptability, and phenotypic stability and are thus indicated for cultivation in the first and second groups of environments, respectively.

Saccharomyces cerevisiae metabolism in ecological context.

PubMed

Jouhten, Paula; Ponomarova, Olga; Gonzalez, Ramon; Patil, Kiran R

2016-11-01

The architecture and regulation of Saccharomyces cerevisiae metabolic network are among the best studied owing to its widespread use in both basic research and industry. Yet, several recent studies have revealed notable limitations in explaining genotype-metabolic phenotype relations in this yeast, especially when concerning multiple genetic/environmental perturbations. Apparently unexpected genotype-phenotype relations may originate in the evolutionarily shaped cellular operating principles being hidden in common laboratory conditions. Predecessors of laboratory S. cerevisiae strains, the wild and the domesticated yeasts, have been evolutionarily shaped by highly variable environments, very distinct from laboratory conditions, and most interestingly by social life within microbial communities. Here we present a brief review of the genotypic and phenotypic peculiarities of S. cerevisiae in the context of its social lifestyle beyond laboratory environments. Accounting for this ecological context and the origin of the laboratory strains in experimental design and data analysis would be essential in improving the understanding of genotype-environment-phenotype relationships. © FEMS 2016.

Precision and Error of Three-dimensional Phenotypic Measures Acquired from 3dMD Photogrammetric Images

PubMed Central

Aldridge, Kristina; Boyadjiev, Simeon A.; Capone, George T.; DeLeon, Valerie B.; Richtsmeier, Joan T.

2015-01-01

The genetic basis for complex phenotypes is currently of great interest for both clinical investigators and basic scientists. In order to acquire a thorough understanding of the translation from genotype to phenotype, highly precise measures of phenotypic variation are required. New technologies, such as 3D photogrammetry are being implemented in phenotypic studies due to their ability to collect data rapidly and non-invasively. Before these systems can be broadly implemented the error associated with data collected from images acquired using these technologies must be assessed. This study investigates the precision, error, and repeatability associated with anthropometric landmark coordinate data collected from 3D digital photogrammetric images acquired with the 3dMDface System. Precision, error due to the imaging system, error due to digitization of the images, and repeatability are assessed in a sample of children and adults (N=15). Results show that data collected from images with the 3dMDface System are highly repeatable and precise. The average error associated with the placement of landmarks is sub-millimeter; both the error due to digitization and to the imaging system are very low. The few measures showing a higher degree of error include those crossing the labial fissure, which are influenced by even subtle movement of the mandible. These results suggest that 3D anthropometric data collected using the 3dMDface System are highly reliable and therefore useful for evaluation of clinical dysmorphology and surgery, analyses of genotype-phenotype correlations, and inheritance of complex phenotypes. PMID:16158436

Delineation of C12orf65-related phenotypes: a genotype-phenotype relationship.

PubMed

Spiegel, Ronen; Mandel, Hanna; Saada, Ann; Lerer, Issy; Burger, Ayala; Shaag, Avraham; Shalev, Stavit A; Jabaly-Habib, Haneen; Goldsher, Dorit; Gomori, John M; Lossos, Alex; Elpeleg, Orly; Meiner, Vardiella

2014-08-01

C12orf65 participates in the process of mitochondrial translation and has been shown to be associated with a spectrum of phenotypes, including early onset optic atrophy, progressive encephalomyopathy, peripheral neuropathy, and spastic paraparesis.We used whole-genome homozygosity mapping as well as exome sequencing and targeted gene sequencing to identify novel C12orf65 disease-causing mutations in seven affected individuals originating from two consanguineous families. In four family members affected with childhood-onset optic atrophy accompanied by slowly progressive peripheral neuropathy and spastic paraparesis, we identified a homozygous frame shift mutation c.413_417 delAACAA, which predicts a truncated protein lacking the C-terminal portion. In the second family, we studied three affected individuals who presented with early onset optic atrophy, peripheral neuropathy, and spastic gait in addition to moderate intellectual disability. Muscle biopsy in two of the patients revealed decreased activities of the mitochondrial respiratory chain complexes I and IV. In these patients, we identified a homozygous splice mutation, g.21043 T>A (c.282+2 T>A) which leads to skipping of exon 2. Our study broadens the phenotypic spectrum of C12orf65 defects and highlights the triad of optic atrophy, axonal neuropathy and spastic paraparesis as its key clinical features. In addition, a clear genotype-phenotype correlation is anticipated in which deleterious mutations which disrupt the GGQ-containing domain in the first coding exon are expected to result in a more severe phenotype, whereas down-stream C-terminal mutations may result in a more favorable phenotype, typically lacking cognitive impairment.

Relevance and costs of RHD genotyping in women with a weak D phenotype.

PubMed

Laget, L; Izard, C; Durieux-Roussel, E; Gouvitsos, J; Dettori, I; Chiaroni, J; Ferrera-Tourenc, V

2018-06-01

For pregnant women, the serologic test results of D antigen will determine the frequency of RBC antibody detection as well as the indication for RhIG prophylaxis. RHD genotyping is the only method that may provide clear guidance on prophylaxis for women with a weak D phenotype. This analysis evaluated the economical implications of using RHD genotyping to guide RhIG prophylaxis among pregnant women with a serological weak D phenotype. We compared the costs of 2 strategies in a cohort of 273 women with weak D phenotype. In the first strategy, we did not perform genotyping and all women with weak D phenotypes were treated as if they were D-, thus considered to be a risk of RhD alloimmunization. These women all received the prophylactic follow up. In the second strategy, RHD genotyping was performed on all women with a serologic weak D phenotype. Then, the follow-up will be determined by phenotype deduced from genotype. On the studied cohort, the additional expense occurred by genotyping is 26,536 €. RHD Genotyping has highlighted 162 weak D Type 1, 2 3, that could safely be managed as D+ and 111 partial D to consider as D-. By comparing the 2 strategies, the savings generated by genotyping the patients of our cohort are € 12,046 for the follow up of one pregnancy. Knowing that in France, a woman has on average 2 pregnancies and that the genotyping is carried out only once, the savings generated for the following pregnancies would be € 38,581. Performing RHD genotyping for pregnant women with a weak D phenotype enables to clearly identify weak D type 1, 2 or 3 from the other variants at risk of alloimmunization. This analysis generates savings in terms of follow-up schedule of pregnant women and RhIG prophylaxis. It also allows saving of D- products for patient with a weak D type 1, 2 or 3 in case of a transfusion need. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Phenotypes in defined genotypes including siblings with Usher syndrome.

PubMed

Malm, Eva; Ponjavic, Vesna; Möller, Claes; Kimberling, William J; Andréasson, Sten

2011-06-01

To characterize visual function in defined genotypes including siblings with Usher syndrome. Thirteen patients with phenotypically different subtypes of Usher syndrome, including 3 families with affected siblings, were selected. Genetic analysis and ophthalmological examinations including visual fields, full-field electroretinography (ERG), multifocal electroretinography (mf ERG), and optical coherence tomography (OCT) were assessed. The patients' degree of visual handicap was evaluated by a questionnaire (ADL). Twelve of thirteen patients were genotyped as Usher 1B, 1D, 1F, 2A, 2C or 3A. In 12 of 13 patients examined with ERG the 30 Hz flickering light response revealed remaining cone function. In 3 of the patients with Usher type 1 mf ERG demonstrated a specific pattern, with a sharp distinction between the area with reduced function and the central area with remaining macular function and normal peak time. OCT demonstrated loss of foveal depression with distortion of the foveal architecture in the macula in all patients. The foveal thickness ranged from 159 to 384 µm and was not correlated to retinal function. Three siblings shared the same mutation for Usher 2C but in contrast to previous reports regarding this genotype, 1 of them diverged in phenotype with substantially normal visual fields, almost normal OCT and mf ERG findings, and only moderately reduced rod and cone function according to ERG. Evaluation of visual function comprising both the severity of the rod cone degeneration and the function in the macular region confirm phenotypical heterogeneity within siblings and between different genotypes of Usher syndrome.

Correlation of ultra-widefield fundus autofluorescence patterns with the underlying genotype in retinal dystrophies and retinitis pigmentosa.

PubMed

Trichonas, George; Traboulsi, Elias I; Ehlers, Justis P

2017-01-01

Ultra-widefield fundus autofluorescence (UW-FAF) allows the characterization of the peripheral retinal features of vitreoretinal diseases. The purpose of this study was to examine possible genotypic/phenotypic correlations of UW-FAF patterns in patients with a variety of retinal dystrophies and retinitis pigmentosa (RP). An IRB-approved retrospective consecutive case series study was performed of genetically characterized retinal dystrophy or RP patients who underwent UW-FAF imaging. UW-FAF was performed with the Optos 200Tx system. Clinical variables, genotypic analysis, and phenotypic characteristics were reviewed. Seventeen patients were identified who had identified mutations in retinal dystrophy or RP genes and who also had undergone UW-FAF. Three patients had X-linked RP with RPGR mutations. Six patients had autosomal dominant RP (four with RHO mutations and one with a PRPF31 mutation, and one with RDS/PRPH2 mutation). Four patients had autosomal recessive RP (four with USH2A mutations). Three patients had Leber Congenital Amaurosis (LCA) with mutations including CRB1, CEP290, and RPGRIP1. Macular hyperautofluorescence was noted in all patients. A ring of hyperautofluorescence was clear in patients with RHO and USH2A mutations, and patients with USH2A mutations demonstrated a second ring of hyperautofluorescence. In the periphery, patients with RHO or RPGR mutations exhibited hyperautofluorescence with patchy areas of hypoautofluorescence. Patients with USH2A mutations had a distinctive pattern of diffuse and homogeneous peripheral hypoautofluorescence. UW-FAF may provide important information to facilitate diagnosis and further research is needed to better characterize this technology as an imaging biomarker for genotype association in retinal dystrophies and RP.

WWOX-related encephalopathies: delineation of the phenotypical spectrum and emerging genotype-phenotype correlation.

PubMed

Mignot, Cyril; Lambert, Laetitia; Pasquier, Laurent; Bienvenu, Thierry; Delahaye-Duriez, Andrée; Keren, Boris; Lefranc, Jérémie; Saunier, Aline; Allou, Lila; Roth, Virginie; Valduga, Mylène; Moustaïne, Aissa; Auvin, Stéphane; Barrey, Catherine; Chantot-Bastaraud, Sandra; Lebrun, Nicolas; Moutard, Marie-Laure; Nougues, Marie-Christine; Vermersch, Anne-Isabelle; Héron, Bénédicte; Pipiras, Eva; Héron, Delphine; Olivier-Faivre, Laurence; Guéant, Jean-Louis; Jonveaux, Philippe; Philippe, Christophe

2015-01-01

Homozygous mutations in WWOX were reported in eight individuals of two families with autosomal recessive spinocerebellar ataxia type 12 and in two siblings with infantile epileptic encephalopathy (IEE), including one who deceased prior to DNA sampling. By combining array comparative genomic hybridisation, targeted Sanger sequencing and next generation sequencing, we identified five further patients from four families with IEE due to biallelic alterations of WWOX. We identified eight deleterious WWOX alleles consisting in four deletions, a four base-pair frameshifting deletion, one missense and two nonsense mutations. Genotype-phenotype correlation emerges from the seven reported families. The phenotype in four patients carrying two predicted null alleles was characterised by (1) little if any psychomotor acquisitions, poor spontaneous motility and absent eye contact from birth, (2) pharmacoresistant epilepsy starting in the 1st weeks of life, (3) possible retinal degeneration, acquired microcephaly and premature death. This contrasted with the less severe autosomal recessive spinocerebellar ataxia type 12 phenotype due to hypomorphic alleles. In line with this correlation, the phenotype in two siblings carrying a null allele and a missense mutation was intermediate. Our results obtained by a combination of different molecular techniques undoubtedly incriminate WWOX as a gene for recessive IEE and illustrate the usefulness of high throughput data mining for the identification of genes for rare autosomal recessive disorders. The structure of the WWOX locus encompassing the FRA16D fragile site might explain why constitutive deletions are recurrently reported in genetic databases, suggesting that WWOX-related encephalopathies, although likely rare, may not be exceptional. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Heritabilities and genetic correlations in the same traits across different strata of herds created according to continuous genomic, genetic, and phenotypic descriptors.

PubMed

Yin, Tong; König, Sven

2018-03-01

The most common approach in dairy cattle to prove genotype by environment interactions is a multiple-trait model application, and considering the same traits in different environments as different traits. We enhanced such concepts by defining continuous phenotypic, genetic, and genomic herd descriptors, and applying random regression sire models. Traits of interest were test-day traits for milk yield, fat percentage, protein percentage, and somatic cell score, considering 267,393 records from 32,707 first-lactation Holstein cows. Cows were born in the years 2010 to 2013, and kept in 52 large-scale herds from 2 federal states of north-east Germany. The average number of genotyped cows per herd (45,613 single nucleotide polymorphism markers per cow) was 133.5 (range: 45 to 415 genotyped cows). Genomic herd descriptors were (1) the level of linkage disequilibrium (r 2 ) within specific chromosome segments, and (2) the average allele frequency for single nucleotide polymorphisms in close distance to a functional mutation. Genetic herd descriptors were the (1) intra-herd inbreeding coefficient, and (2) the percentage of daughters from foreign sires. Phenotypic herd descriptors were (1) herd size, and (2) the herd mean for nonreturn rate. Most correlations among herd descriptors were close to 0, indicating independence of genomic, genetic, and phenotypic characteristics. Heritabilities for milk yield increased with increasing intra-herd linkage disequilibrium, inbreeding, and herd size. Genetic correlations in same traits between adjacent levels of herd descriptors were close to 1, but declined for descriptor levels in greater distance. Genetic correlation declines were more obvious for somatic cell score, compared with test-day traits with larger heritabilities (fat percentage and protein percentage). Also, for milk yield, alterations of herd descriptor levels had an obvious effect on heritabilities and genetic correlations. By trend, multiple trait model results (based on created discrete herd classes) confirmed the random regression estimates. Identified alterations of breeding values in dependency of herd descriptors suggest utilization of specific sires for specific herd structures, offering new possibilities to improve sire selection strategies. Regarding genomic selection designs and genetic gain transfer into commercial herds, cow herds for the utilization in cow training sets should reflect the genomic, genetic, and phenotypic pattern of the broad population. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Selection for production-related traits in Pelargonium zonale: improved design and analysis make all the difference

PubMed Central

Molenaar, Heike; Glawe, Martin; Boehm, Robert; Piepho, Hans-Peter

2017-01-01

Ornamental plant variety improvement is limited by current phenotyping approaches and neglected use of experimental designs. The present study was conducted to show the benefits of using an experimental design and corresponding analysis in ornamental breeding regarding simulated response to selection in Pelargonium zonale for production-related traits. This required establishment of phenotyping protocols for root formation and stem cutting counts, with which 974 genotypes were assessed in a two-phase experimental design. The present paper evaluates this protocol. The possibility of varietal improvement through indirect selection on secondary traits such as branch count and flower count was assessed by genetic correlations. Simulated response to selection varied greatly, depending on the genotypic variances of the breeding population and traits. A varietal improvement of over 20% is possible for stem cutting count, root formation, branch count and flower count. In contrast, indirect selection of stem cutting count by branch count or flower count was found to be ineffective. The established phenotypic protocols and two-phase experimental designs are valuable tools for breeding of P. zonale. PMID:28243453

Selection for production-related traits in Pelargonium zonale: improved design and analysis make all the difference.

PubMed

Molenaar, Heike; Glawe, Martin; Boehm, Robert; Piepho, Hans-Peter

2017-01-01

Ornamental plant variety improvement is limited by current phenotyping approaches and neglected use of experimental designs. The present study was conducted to show the benefits of using an experimental design and corresponding analysis in ornamental breeding regarding simulated response to selection in Pelargonium zonale for production-related traits. This required establishment of phenotyping protocols for root formation and stem cutting counts, with which 974 genotypes were assessed in a two-phase experimental design. The present paper evaluates this protocol. The possibility of varietal improvement through indirect selection on secondary traits such as branch count and flower count was assessed by genetic correlations. Simulated response to selection varied greatly, depending on the genotypic variances of the breeding population and traits. A varietal improvement of over 20% is possible for stem cutting count, root formation, branch count and flower count. In contrast, indirect selection of stem cutting count by branch count or flower count was found to be ineffective. The established phenotypic protocols and two-phase experimental designs are valuable tools for breeding of P. zonale .

Phenotypic convergence in bacterial adaptive evolution to ethanol stress.

PubMed

Horinouchi, Takaaki; Suzuki, Shingo; Hirasawa, Takashi; Ono, Naoaki; Yomo, Tetsuya; Shimizu, Hiroshi; Furusawa, Chikara

2015-09-03

Bacterial cells have a remarkable ability to adapt to environmental changes, a phenomenon known as adaptive evolution. During adaptive evolution, phenotype and genotype dynamically changes; however, the relationship between these changes and associated constraints is yet to be fully elucidated. In this study, we analyzed phenotypic and genotypic changes in Escherichia coli cells during adaptive evolution to ethanol stress. Phenotypic changes were quantified by transcriptome and metabolome analyses and were similar among independently evolved ethanol tolerant populations, which indicate the existence of evolutionary constraints in the dynamics of adaptive evolution. Furthermore, the contribution of identified mutations in one of the tolerant strains was evaluated using site-directed mutagenesis. The result demonstrated that the introduction of all identified mutations cannot fully explain the observed tolerance in the tolerant strain. The results demonstrated that the convergence of adaptive phenotypic changes and diverse genotypic changes, which suggested that the phenotype-genotype mapping is complex. The integration of transcriptome and genome data provides a quantitative understanding of evolutionary constraints.

A Comprehensive Analysis of Choroideremia: From Genetic Characterization to Clinical Practice

PubMed Central

Sanchez-Alcudia, Rocio; Garcia-Hoyos, Maria; Lopez-Martinez, Miguel Angel; Sanchez-Bolivar, Noelia; Zurita, Olga; Gimenez, Ascension; Villaverde, Cristina; Rodrigues-Jacy da Silva, Luciana; Corton, Marta; Perez-Carro, Raquel; Torriano, Simona; Kalatzis, Vasiliki; Rivolta, Carlo; Avila-Fernandez, Almudena; Lorda, Isabel; Trujillo-Tiebas, Maria J.; Garcia-Sandoval, Blanca; Lopez-Molina, Maria Isabel; Blanco-Kelly, Fiona; Riveiro-Alvarez, Rosa; Ayuso, Carmen

2016-01-01

Choroideremia (CHM) is a rare X-linked disease leading to progressive retinal degeneration resulting in blindness. The disorder is caused by mutations in the CHM gene encoding REP-1 protein, an essential component of the Rab geranylgeranyltransferase (GGTase) complex. In the present study, we evaluated a multi-technique analysis algorithm to describe the mutational spectrum identified in a large cohort of cases and further correlate CHM variants with phenotypic characteristics and biochemical defects of choroideremia patients. Molecular genetic testing led to the characterization of 36 out of 45 unrelated CHM families (80%), allowing the clinical reclassification of four CHM families. Haplotype reconstruction showed independent origins for the recurrent p.Arg293* and p.Lys178Argfs*5 mutations, suggesting the presence of hotspots in CHM, as well as the identification of two different unrelated events involving exon 9 deletion. No certain genotype-phenotype correlation could be established. Furthermore, all the patients´ fibroblasts analyzed presented significantly increased levels of unprenylated Rabs proteins compared to control cells; however, this was not related to the genotype. This research demonstrates the major potential of the algorithm proposed for diagnosis. Our data enhance the importance of establish a differential diagnosis with other retinal dystrophies, supporting the idea of an underestimated prevalence of choroideremia. Moreover, they suggested that the severity of the disorder cannot be exclusively explained by the genotype. PMID:27070432

Applying semantic web technologies for phenome-wide scan using an electronic health record linked Biobank

PubMed Central

2012-01-01

Background The ability to conduct genome-wide association studies (GWAS) has enabled new exploration of how genetic variations contribute to health and disease etiology. However, historically GWAS have been limited by inadequate sample size due to associated costs for genotyping and phenotyping of study subjects. This has prompted several academic medical centers to form “biobanks” where biospecimens linked to personal health information, typically in electronic health records (EHRs), are collected and stored on a large number of subjects. This provides tremendous opportunities to discover novel genotype-phenotype associations and foster hypotheses generation. Results In this work, we study how emerging Semantic Web technologies can be applied in conjunction with clinical and genotype data stored at the Mayo Clinic Biobank to mine the phenotype data for genetic associations. In particular, we demonstrate the role of using Resource Description Framework (RDF) for representing EHR diagnoses and procedure data, and enable federated querying via standardized Web protocols to identify subjects genotyped for Type 2 Diabetes and Hypothyroidism to discover gene-disease associations. Our study highlights the potential of Web-scale data federation techniques to execute complex queries. Conclusions This study demonstrates how Semantic Web technologies can be applied in conjunction with clinical data stored in EHRs to accurately identify subjects with specific diseases and phenotypes, and identify genotype-phenotype associations. PMID:23244446

Genotype-Phenotype Correlation of SCN5A Mutation for the Clinical and Electrocardiographic Characteristics of Probands With Brugada Syndrome: A Japanese Multicenter Registry.

PubMed

Yamagata, Kenichiro; Horie, Minoru; Aiba, Takeshi; Ogawa, Satoshi; Aizawa, Yoshifusa; Ohe, Tohru; Yamagishi, Masakazu; Makita, Naomasa; Sakurada, Harumizu; Tanaka, Toshihiro; Shimizu, Akihiko; Hagiwara, Nobuhisa; Kishi, Ryoji; Nakano, Yukiko; Takagi, Masahiko; Makiyama, Takeru; Ohno, Seiko; Fukuda, Keiichi; Watanabe, Hiroshi; Morita, Hiroshi; Hayashi, Kenshi; Kusano, Kengo; Kamakura, Shiro; Yasuda, Satoshi; Ogawa, Hisao; Miyamoto, Yoshihiro; Kapplinger, Jamie D; Ackerman, Michael J; Shimizu, Wataru

2017-06-06

The genotype-phenotype correlation of SCN5A mutations as a predictor of cardiac events in Brugada syndrome remains controversial. We aimed to establish a registry limited to probands, with a long follow-up period, so that the genotype-phenotype correlation of SCN5A mutations in Brugada syndrome can be examined without patient selection bias. This multicenter registry enrolled 415 probands (n=403; men, 97%; age, 46±14 years) diagnosed with Brugada syndrome whose SCN5A gene was analyzed for mutations. During a mean follow-up period of 72 months, the overall cardiac event rate was 2.5%/y. In comparison with probands without mutations ( SCN5A (-), n=355), probands with SCN5A mutations ( SCN5A (+), n=60) experienced their first cardiac event at a younger age (34 versus 42 years, P =0.013), had a higher positive rate of late potentials (89% versus 73%, P =0.016), exhibited longer P-wave, PQ, and QRS durations, and had a higher rate of cardiac events ( P =0.017 by log-rank). Multivariate analysis indicated that only SCN5A mutation and history of aborted cardiac arrest were significant predictors of cardiac events ( SCN5A (+) versus SCN5A (-): hazard ratio, 2.0 and P =0.045; history of aborted cardiac arrest versus no such history: hazard ratio, 6.5 and P <0.001). Brugada syndrome patients with SCN5A mutations exhibit more conduction abnormalities on ECG and have higher risk for cardiac events. © 2017 American Heart Association, Inc.

NCI Workshop Report: Clinical and Computational Requirements for Correlating Imaging Phenotypes with Genomics Signatures.

PubMed

Colen, Rivka; Foster, Ian; Gatenby, Robert; Giger, Mary Ellen; Gillies, Robert; Gutman, David; Heller, Matthew; Jain, Rajan; Madabhushi, Anant; Madhavan, Subha; Napel, Sandy; Rao, Arvind; Saltz, Joel; Tatum, James; Verhaak, Roeland; Whitman, Gary

2014-10-01

The National Cancer Institute (NCI) Cancer Imaging Program organized two related workshops on June 26-27, 2013, entitled "Correlating Imaging Phenotypes with Genomics Signatures Research" and "Scalable Computational Resources as Required for Imaging-Genomics Decision Support Systems." The first workshop focused on clinical and scientific requirements, exploring our knowledge of phenotypic characteristics of cancer biological properties to determine whether the field is sufficiently advanced to correlate with imaging phenotypes that underpin genomics and clinical outcomes, and exploring new scientific methods to extract phenotypic features from medical images and relate them to genomics analyses. The second workshop focused on computational methods that explore informatics and computational requirements to extract phenotypic features from medical images and relate them to genomics analyses and improve the accessibility and speed of dissemination of existing NIH resources. These workshops linked clinical and scientific requirements of currently known phenotypic and genotypic cancer biology characteristics with imaging phenotypes that underpin genomics and clinical outcomes. The group generated a set of recommendations to NCI leadership and the research community that encourage and support development of the emerging radiogenomics research field to address short-and longer-term goals in cancer research.

Epistasis and Pleiotropy Affect the Modularity of the Genotype-Phenotype Map of Cross-Resistance in HIV-1.

PubMed

Polster, Robert; Petropoulos, Christos J; Bonhoeffer, Sebastian; Guillaume, Frédéric

2016-12-01

The genotype-phenotype (GP) map is a central concept in evolutionary biology as it describes the mapping of molecular genetic variation onto phenotypic trait variation. Our understanding of that mapping remains partial, especially when trying to link functional clustering of pleiotropic gene effects with patterns of phenotypic trait co-variation. Only on rare occasions have studies been able to fully explore that link and tend to show poor correspondence between modular structures within the GP map and among phenotypes. By dissecting the structure of the GP map of the replicative capacity of HIV-1 in 15 drug environments, we provide a detailed view of that mapping from mutational pleiotropic variation to phenotypic co-variation, including epistatic effects of a set of amino-acid substitutions in the reverse transcriptase and protease genes. We show that epistasis increases the pleiotropic degree of single mutations and provides modularity to the GP map of drug resistance in HIV-1. Moreover, modules of epistatic pleiotropic effects within the GP map match the phenotypic modules of correlated replicative capacity among drug classes. Epistasis thus increases the evolvability of cross-resistance in HIV by providing more drug- and class-specific pleiotropic profiles to the main effects of the mutations. We discuss the implications for the evolution of cross-resistance in HIV. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Osteogenesis imperfecta type V: Genetic and clinical findings in eleven Chinese patients.

PubMed

Liu, Yi; Wang, Jiawei; Ma, Doudou; Lv, Fang; Xu, Xiaojie; Xia, Weibo; Jiang, Yan; Wang, Ou; Xing, Xiaoping; Zhou, Peiran; Wang, Jianyi; Yu, Wei; Li, Mei

2016-11-01

Osteogenesis imperfecta (OI) type V is a rare inherited disease characterized by multiple fractures, intraosseous membrane calcification, and hypercallus formation. We investigate the causative gene, phenotype and also observe the effects of zoledronic acid in Chinese OI type V patients. The clinical phenotype and causative gene mutation was investigated in eleven patients with type V OI. Patients were given a dose of zoledronic acid 5mg intravenously. Fracture incidence and Z-score of bone mineral density (BMD) were evaluated. Serum levels of biomarkers such as cross linked C-telopeptide of type I collagen (β-CTX) and safety parameters were assessed. The c.-14C>T mutation in the 5' untranslated region of IFITM5 was detected in all patients. The phenotype was largely variable, and no significant correlation of genotype and phenotype was found. After one dose of zoledronic acid infusion, fracture incidence significantly dropped from 2fractures/year before treatment to 0fracture/year after treatment (P=0.01). Z score of lumbar spine BMD elevated from -2.6 to -1.3 (P<0.001). Serum β-CTX level decreased by 50% (P<0.05). No serious adverse event was found. No obvious correlation was found between the genotype and phenotype. Zoledronic acid had significantly skeletal protective effects in OI of type V. Copyright © 2016 Elsevier B.V. All rights reserved.

Genotypes of Brassica rapa respond differently to plant-induced variation in air CO2 concentration in growth chambers with standard and enhanced venting.

PubMed

Edwards, Christine E; Haselhorst, Monia S H; McKnite, Autumn M; Ewers, Brent E; Williams, David G; Weinig, Cynthia

2009-10-01

Growth chambers allow measurement of phenotypic differences among genotypes under controlled environment conditions. However, unintended variation in growth chamber air CO2 concentration ([CO2]) may affect the expression of diverse phenotypic traits, and genotypes may differ in their response to variation in [CO2]. We monitored [CO2] and quantified phenotypic responses of 22 Brassica rapa genotypes in growth chambers with either standard or enhanced venting. [CO2] in chambers with standard venting dropped to 280 micromol mol(-1) during the period of maximum canopy development, approximately 80 micromol mol(-1) lower than in chambers with enhanced venting. The stable carbon isotope ratio of CO2 in chamber air (delta13C(air)) was negatively correlated with [CO2], suggesting that photosynthesis caused observed [CO2] decreases. Significant genotype x chamber-venting interactions were detected for 12 of 20 traits, likely due to differences in the extent to which [CO2] changed in relation to genotypes' phenology or differential sensitivity of genotypes to low [CO2]. One trait, 13C discrimination (delta13C), was particularly influenced by unaccounted-for fluctuations in delta13C(air) and [CO2]. Observed responses to [CO2] suggest that genetic variance components estimated in poorly vented growth chambers may be influenced by the expression of genes involved in CO2 stress responses; genotypic values estimated in these chambers may likewise be misleading such that some mapped quantitative trait loci may regulate responses to CO2 stress rather than a response to the environmental factor of interest. These results underscore the importance of monitoring, and where possible, controlling [CO2].

Genetic Basis and Genetic Modifiers of β-Thalassemia and Sickle Cell Disease.

PubMed

Thein, Swee Lay

2017-01-01

β-thalassemia and sickle cell disease (SCD) are prototypical Mendelian single gene disorders, both caused by mutations affecting the adult β-globin gene. Despite the apparent genetic simplicity, both disorders display a remarkable spectrum of phenotypic severity and share two major genetic modifiers-α-globin genotype and innate ability to produce fetal hemoglobin (HbF, α 2 γ 2 ).This article provides an overview of the genetic basis for SCD and β-thalassemia, and genetic modifiers identified through phenotype correlation studies. Identification of the genetic variants modifying HbF production in combination with α-globin genotype provide some prediction of disease severity for β-thalassemia and SCD but generation of a personalized genetic risk score to inform prognosis and guide management requires a larger panel of genetic modifiers yet to be discovered.Nonetheless, genetic studies have been successful in characterizing some of the key variants and pathways involved in HbF regulation, providing new therapeutic targets for HbF reactivation.

Distribution of genotype network sizes in sequence-to-structure genotype-phenotype maps.

PubMed

Manrubia, Susanna; Cuesta, José A

2017-04-01

An essential quantity to ensure evolvability of populations is the navigability of the genotype space. Navigability, understood as the ease with which alternative phenotypes are reached, relies on the existence of sufficiently large and mutually attainable genotype networks. The size of genotype networks (e.g. the number of RNA sequences folding into a particular secondary structure or the number of DNA sequences coding for the same protein structure) is astronomically large in all functional molecules investigated: an exhaustive experimental or computational study of all RNA folds or all protein structures becomes impossible even for moderately long sequences. Here, we analytically derive the distribution of genotype network sizes for a hierarchy of models which successively incorporate features of increasingly realistic sequence-to-structure genotype-phenotype maps. The main feature of these models relies on the characterization of each phenotype through a prototypical sequence whose sites admit a variable fraction of letters of the alphabet. Our models interpolate between two limit distributions: a power-law distribution, when the ordering of sites in the prototypical sequence is strongly constrained, and a lognormal distribution, as suggested for RNA, when different orderings of the same set of sites yield different phenotypes. Our main result is the qualitative and quantitative identification of those features of sequence-to-structure maps that lead to different distributions of genotype network sizes. © 2017 The Author(s).

Genetics Home Reference: congenital adrenal hyperplasia due to 11-beta-hydroxylase deficiency

MedlinePlus

... Shackleton C, Imperato-McGinley J. Mutations in CYP11B1 gene: phenotype-genotype correlations. Am J Med Genet A. 2003 Oct ... are genome editing and CRISPR-Cas9? What is precision medicine? What ...

High Throughput Computing Impact on Meta Genomics (Metagenomics Informatics Challenges Workshop: 10K Genomes at a Time)

ScienceCinema

Gore, Brooklin

2018-02-01

This presentation includes a brief background on High Throughput Computing, correlating gene transcription factors, optical mapping, genotype to phenotype mapping via QTL analysis, and current work on next gen sequencing.

Segregating polymorphisms of FOXP2 are associated with measures of inner speech, speech fluency and strength of handedness in a healthy population.

PubMed

Crespi, Bernard; Read, Silven; Hurd, Peter

2017-10-01

We genotyped a healthy population for three haplotype-tagging FOXP2 SNPs, and tested for associations of these SNPs with strength of handedness and questionnaire-based metrics of inner speech characteristics (ISP) and speech fluency (FLU), as derived from the Schizotypal Personality Questionnaire-BR. Levels of mixed-handedness were positively correlated with ISP and FLU, supporting prior work on these two domains. Genotype for rs7799109, a SNP previously linked with lateralization of left frontal regions underlying language, was associated with degree of mixed handedness and with scores for ISP and FLU phenotypes. Genotype of rs1456031, which has previously been linked with auditory hallucinations, was also associated with ISP phenotypes. These results provide evidence that FOXP2 SNPs influence aspects of human inner speech and fluency that are related to lateralized phenotypes, and suggest that the evolution of human language, as mediated by the adaptive evolution of FOXP2, involved features of inner speech. Copyright © 2017 Elsevier Inc. All rights reserved.

Genotypic and Phenotypic Characteristics Associated with Biofilm Formation by Human Clinical Escherichia coli Isolates of Different Pathotypes.

PubMed

Schiebel, Juliane; Böhm, Alexander; Nitschke, Jörg; Burdukiewicz, Michał; Weinreich, Jörg; Ali, Aamir; Roggenbuck, Dirk; Rödiger, Stefan; Schierack, Peter

2017-12-15

Bacterial biofilm formation is a widespread phenomenon and a complex process requiring a set of genes facilitating the initial adhesion, maturation, and production of the extracellular polymeric matrix and subsequent dispersal of bacteria. Most studies on Escherichia coli biofilm formation have investigated nonpathogenic E. coli K-12 strains. Due to the extensive focus on laboratory strains in most studies, there is poor information regarding biofilm formation by pathogenic E. coli isolates. In this study, we genotypically and phenotypically characterized 187 human clinical E. coli isolates representing various pathotypes (e.g., uropathogenic, enteropathogenic, and enteroaggregative E. coli ). We investigated the presence of biofilm-associated genes ("genotype") and phenotypically analyzed the isolates for motility and curli and cellulose production ("phenotype"). We developed a new screening method to examine the in vitro biofilm formation ability. In summary, we found a high prevalence of biofilm-associated genes. However, we could not detect a biofilm-associated gene or specific phenotype correlating with the biofilm formation ability. In contrast, we did identify an association of increased biofilm formation with a specific E. coli pathotype. Enteroaggregative E. coli (EAEC) was found to exhibit the highest capacity for biofilm formation. Using our image-based technology for the screening of biofilm formation, we demonstrated the characteristic biofilm formation pattern of EAEC, consisting of thick bacterial aggregates. In summary, our results highlight the fact that biofilm-promoting factors shown to be critical for biofilm formation in nonpathogenic strains do not reflect their impact in clinical isolates and that the ability of biofilm formation is a defined characteristic of EAEC. IMPORTANCE Bacterial biofilms are ubiquitous and consist of sessile bacterial cells surrounded by a self-produced extracellular polymeric matrix. They cause chronic and device-related infections due to their high resistance to antibiotics and the host immune system. In nonpathogenic Escherichia coli , cell surface components playing a pivotal role in biofilm formation are well known. In contrast, there is poor information for their role in biofilm formation of pathogenic isolates. Our study provides insights into the correlation of biofilm-associated genes or specific phenotypes with the biofilm formation ability of commensal and pathogenic E. coli Additionally, we describe a newly developed method enabling qualitative biofilm analysis by automated image analysis, which is beneficial for high-throughput screenings. Our results help to establish a better understanding of E. coli biofilm formation. Copyright © 2017 American Society for Microbiology.

Association of a homozygous nonsense mutation in the ABCA4 (ABCR) gene with cone-rod dystrophy phenotype in an Italian family.

PubMed

Simonelli, Francesca; Testa, Francesco; Zernant, Jana; Nesti, Anna; Rossi, Settimio; Rinaldi, Ernesto; Allikmets, Rando

2004-01-01

Genetic variation in the ABCA4 (ABCR) gene has been associated with several distinct retinal phenotypes, including Stargardt disease/fundus flavimaculatus (STGD/FFM), cone-rod dystrophy (CRD), retinitis pigmentosa (RP) and age-related macular degeneration. The current model of genotype/phenotype association suggests that patients harboring deleterious mutations in both ABCR alleles would develop RP-like retinal pathology. Here we describe ABCA4-associated phenotypes, including a proband with a homozygous nonsense mutation in a family from Southern Italy. The proband had been originally diagnosed with STGD. Ophthalmologic examination included kinetic perimetry, electrophysiological studies and fluorescein angiography. DNA of the affected individual and family members was analyzed for variants in all 50 exons of the ABCA4 gene by screening on the ABCR400 microarray. A homozygous nonsense mutation 2971G>T (G991X) was detected in a patient initially diagnosed with STGD based on funduscopic evidence, including bull's eye depigmentation of the fovea and flecks at the posterior pole extending to the mid-peripheral retina. Since this novel nucleotide substitution results in a truncated, nonfunctional, ABCA4 protein, the patient was examined in-depth for the severity of the disease phenotype. Indeed, subsequent electrophysiological studies determined severely reduced cone amplitude as compared to the rod amplitude, suggesting the diagnosis of CRD. ABCR400 microarray is an efficient tool for determining causal genetic variation, including new mutations. A homozygous protein-truncating mutation in ABCA4 can cause a phenotype ranging from STGD to CRD as diagnosed at an early stage of the disease. Only a combination of comprehensive genotype/phenotype correlation studies will determine the proper diagnosis and prognosis of ABCA4-associated pathology. Copyright 2004 S. Karger AG, Basel

Identifying pleiotropic genes in genome-wide association studies from related subjects using the linear mixed model and Fisher combination function.

PubMed

Yang, James J; Williams, L Keoki; Buu, Anne

2017-08-24

A multivariate genome-wide association test is proposed for analyzing data on multivariate quantitative phenotypes collected from related subjects. The proposed method is a two-step approach. The first step models the association between the genotype and marginal phenotype using a linear mixed model. The second step uses the correlation between residuals of the linear mixed model to estimate the null distribution of the Fisher combination test statistic. The simulation results show that the proposed method controls the type I error rate and is more powerful than the marginal tests across different population structures (admixed or non-admixed) and relatedness (related or independent). The statistical analysis on the database of the Study of Addiction: Genetics and Environment (SAGE) demonstrates that applying the multivariate association test may facilitate identification of the pleiotropic genes contributing to the risk for alcohol dependence commonly expressed by four correlated phenotypes. This study proposes a multivariate method for identifying pleiotropic genes while adjusting for cryptic relatedness and population structure between subjects. The two-step approach is not only powerful but also computationally efficient even when the number of subjects and the number of phenotypes are both very large.

Differences in hepatic phenotype between hemochromatosis patients with HFE C282Y homozygosity and other HFE genotypes.

PubMed

Cheng, Raymond; Barton, James C; Morrison, Elizabeth D; Phatak, Pradyumna D; Krawitt, Edward L; Gordon, Stuart C; Kowdley, Kris V

2009-07-01

There are limited data comparing hepatic phenotype among hemochromatosis patients with different HFE genotypes. The goal of this study was to compare hepatic histopathologic features and hepatic iron concentration (HIC) among patients with phenotypic hemochromatosis and different HFE genotypes. We studied 182 US patients with phenotypic hemochromatosis. Degree of hepatic fibrosis, pattern of iron deposition, presence of steatosis or necroinflammation, and HIC were compared among different HFE genotypes. C282Y/H63D compound heterozygotes and patients with HFE genotypes other than C282Y/C282Y were more likely to have stainable Kupffer cell iron (31.1% vs. 9.5%; P=0.02), portal or lobular inflammation (28.9% vs. 15.6%; P=0.03), and steatosis (33.3% vs. 10.2%; P<0.01) on liver biopsy than C282Y homozygotes. Mean log10 HIC (P<0.05) and log10 ferritin (P<0.05) were higher among C282Y homozygotes than in patients with other HFE genotypes. In a logistic regression analysis using age, sex, HFE genotype, log10 ferritin, and log10 HIC as independent variables, log10 serum ferritin (P=0.0008), male sex (P=0.0086), and log10 HIC (P=0.047), but not HFE genotype (P=0.0554) were independently associated with presence or absence of advanced hepatic fibrosis. C282Y/H63D compound heterozygotes and other non-C282Y homozygotes which express the hepatic hemochromatosis phenotype frequently have evidence of steatosis or chronic hepatitis and lower body iron stores than C282Y homozygotes. These data suggest that presence of concomitant liver disease may explain expression of the hemochromatosis phenotype among non-C282Y homozygotes. Increased age, HIC, and ferritin are associated with advanced hepatic fibrosis, regardless of HFE genotype.

Phenotype- and genotype-specific structural alterations in spasmodic dysphonia.

PubMed

Bianchi, Serena; Battistella, Giovanni; Huddleston, Hailey; Scharf, Rebecca; Fleysher, Lazar; Rumbach, Anna F; Frucht, Steven J; Blitzer, Andrew; Ozelius, Laurie J; Simonyan, Kristina

2017-04-01

Spasmodic dysphonia is a focal dystonia characterized by involuntary spasms in the laryngeal muscles that occur selectively during speaking. Although hereditary trends have been reported in up to 16% of patients, the causative etiology of spasmodic dysphonia is unclear, and the influences of various phenotypes and genotypes on disorder pathophysiology are poorly understood. In this study, we examined structural alterations in cortical gray matter and white matter integrity in relationship to different phenotypes and putative genotypes of spasmodic dysphonia to elucidate the structural component of its complex pathophysiology. Eighty-nine patients with spasmodic dysphonia underwent high-resolution magnetic resonance imaging and diffusion-weighted imaging to examine cortical thickness and white matter fractional anisotropy in adductor versus abductor forms (distinct phenotypes) and in sporadic versus familial cases (distinct genotypes). Phenotype-specific abnormalities were localized in the left sensorimotor cortex and angular gyrus and the white matter bundle of the right superior corona radiata. Genotype-specific alterations were found in the left superior temporal gyrus, supplementary motor area, and the arcuate portion of the left superior longitudinal fasciculus. Our findings suggest that phenotypic differences in spasmodic dysphonia arise at the level of the primary and associative areas of motor control, whereas genotype-related pathophysiological mechanisms may be associated with dysfunction of regions regulating phonological and sensory processing. Identification of structural alterations specific to disorder phenotype and putative genotype provides an important step toward future delineation of imaging markers and potential targets for novel therapeutic interventions for spasmodic dysphonia. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

Factors and processes modulating phenotypes in neuronopathic lysosomal storage diseases.

PubMed

Jakóbkiewicz-Banecka, Joanna; Gabig-Cimińska, Magdalena; Banecka-Majkutewicz, Zyta; Banecki, Bogdan; Węgrzyn, Alicja; Węgrzyn, Grzegorz

2014-03-01

Lysosomal storage diseases are inherited metabolic disorders caused by genetic defects causing deficiency of various lysosomal proteins, and resultant accumulation of non-degraded compounds. They are multisystemic diseases, and in most of them (>70%) severe brain dysfunctions are evident. However, expression of various phenotypes in particular diseases is extremely variable, from non-neuronopathic to severely neurodegenerative in the deficiency of the same enzyme. Although all lysosomal storage diseases are monogenic, clear genotype-phenotype correlations occur only in some cases. In this article, we present an overview on various factors and processes, both general and specific for certain disorders, that can significantly modulate expression of phenotypes in these diseases. On the basis of recent reports describing studies on both animal models and clinical data, we propose a hypothesis that efficiency of production of compounds that cannot be degraded due to enzyme deficiency might be especially important in modulation of phenotypes of patients suffering from lysosomal storage diseases.

Correlation between connexin 32 gene mutations and clinical phenotype in X-linked dominant Charcot-Marie-Tooth neuropathy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ionasescu, V.; Ionasescu, R.; Searby, C.

1996-06-14

We studied the relationship between the genotype and clinical phenotype in 27 families with dominant X-linked Charcot-Marie-Tooth (CMTX1) neuropathy. Twenty-two families showed mutations in the coding region of the connexin32 (cx32) gene. The mutations include four nonsense mutations, eight missense mutations, two medium size deletions, and one insertion. Most missense mutations showed a mild clinical phenotype (five out of eight), whereas all nonsense mutations, the larger of the two deletions, and the insertion that produced frameshifts showed severe phenotypes. Five CMTX1 families with mild clinical phenotype showed no point mutations of the cx32 gene coding region. Three of these familiesmore » showed positive genetic linkage with the markers of the Xq13.1 region. The genetic linkage of the remaining two families could not be evaluated because of their small size. 25 refs., 1 fig., 1 tab.« less

Clinical phenotype and infertility treatment in a male with hypogonadotropic hypogonadism due to mutations Ala129Asp/Arg262Gln of the gonadotropin-releasing hormone receptor.

PubMed

Layman, Lawrence C; Cohen, David P; Xie, Jun; Smith, Gary D

2002-12-01

To characterize the genotype and phenotype of a man with idiopathic hypogonadism with infertility. Molecular analysis and clinical description. Medical school laboratory and reproductive endocrine clinic.A 40-year-old male with idiopathic hypogonadotropic hypogonadism. Denaturing gradient gel electrophoresis analysis and DNA sequencing of the gonadotropin-releasing hormone receptor (GNRHR) gene were performed. The patient was treated with hCG and FSH. GNRHR mutation detection, genotype/phenotype correlation, and testicular response to exogenous gonadotropin therapy. The proband demonstrated compound heterozygosity for Ala129Asp/Arg262Gln GNRHR mutations. He had a complete form of idiopathic hypogonadotropic hypogonadism, with descended testes and severe oligospermia but little response to exogenous gonadotropins. The phenotype of this patient differs from the one other family described with the same mutations. Exogenous gonadotropin therapy may not be as beneficial for increasing sperm concentration in older men with idiopathic hypogonadotropic hypogonadism.

Treacher Collins syndrome: a clinical and molecular study based on a large series of patients.

PubMed

Vincent, Marie; Geneviève, David; Ostertag, Agnès; Marlin, Sandrine; Lacombe, Didier; Martin-Coignard, Dominique; Coubes, Christine; David, Albert; Lyonnet, Stanislas; Vilain, Catheline; Dieux-Coeslier, Anne; Manouvrier, Sylvie; Isidor, Bertrand; Jacquemont, Marie-Line; Julia, Sophie; Layet, Valérie; Naudion, Sophie; Odent, Sylvie; Pasquier, Laurent; Pelras, Sybille; Philip, Nicole; Pierquin, Geneviève; Prieur, Fabienne; Aboussair, Nisrine; Attie-Bitach, Tania; Baujat, Geneviève; Blanchet, Patricia; Blanchet, Catherine; Dollfus, Hélène; Doray, Bérénice; Schaefer, Elise; Edery, Patrick; Giuliano, Fabienne; Goldenberg, Alice; Goizet, Cyril; Guichet, Agnès; Herlin, Christian; Lambert, Laetitia; Leheup, Bruno; Martinovic, Jelena; Mercier, Sandra; Mignot, Cyril; Moutard, Marie-Laure; Perez, Marie-José; Pinson, Lucile; Puechberty, Jacques; Willems, Marjolaine; Randrianaivo, Hanitra; Szakszon, Kateline; Szaskon, Kateline; Toutain, Annick; Verloes, Alain; Vigneron, Jacqueline; Sanchez, Elodie; Sarda, Pierre; Laplanche, Jean-Louis; Collet, Corinne

2016-01-01

Treacher Collins/Franceschetti syndrome (TCS; OMIM 154500) is a disorder of craniofacial development belonging to the heterogeneous group of mandibulofacial dysostoses. TCS is classically characterized by bilateral mandibular and malar hypoplasia, downward-slanting palpebral fissures, and microtia. To date, three genes have been identified in TCS:,TCOF1, POLR1D, and POLR1C. We report a clinical and extensive molecular study, including TCOF1, POLR1D, POLR1C, and EFTUD2 genes, in a series of 146 patients with TCS. Phenotype-genotype correlations were investigated for 19 clinical features, between TCOF1 and POLR1D, and the type of mutation or its localization in the TCOF1 gene. We identified 92/146 patients (63%) with a molecular anomaly within TCOF1, 9/146 (6%) within POLR1D, and none within POLR1C. Among the atypical negative patients (with intellectual disability and/or microcephaly), we identified four patients carrying a mutation in EFTUD2 and two patients with 5q32 deletion encompassing TCOF1 and CAMK2A in particular. Congenital cardiac defects occurred more frequently among patients with TCOF1 mutation (7/92, 8%) than reported in the literature. Even though TCOF1 and POLR1D were associated with extreme clinical variability, we found no phenotype-genotype correlation. In cases with a typical phenotype of TCS, 6/146 (4%) remained with an unidentified molecular defect.

Genotype-phenotype correlations in individuals with pathogenic RERE variants.

PubMed

Jordan, Valerie K; Fregeau, Brieana; Ge, Xiaoyan; Giordano, Jessica; Wapner, Ronald J; Balci, Tugce B; Carter, Melissa T; Bernat, John A; Moccia, Amanda N; Srivastava, Anshika; Martin, Donna M; Bielas, Stephanie L; Pappas, John; Svoboda, Melissa D; Rio, Marlène; Boddaert, Nathalie; Cantagrel, Vincent; Lewis, Andrea M; Scaglia, Fernando; Kohler, Jennefer N; Bernstein, Jonathan A; Dries, Annika M; Rosenfeld, Jill A; DeFilippo, Colette; Thorson, Willa; Yang, Yaping; Sherr, Elliott H; Bi, Weimin; Scott, Daryl A

2018-05-01

Heterozygous variants in the arginine-glutamic acid dipeptide repeats gene (RERE) have been shown to cause neurodevelopmental disorder with or without anomalies of the brain, eye, or heart (NEDBEH). Here, we report nine individuals with NEDBEH who carry partial deletions or deleterious sequence variants in RERE. These variants were found to be de novo in all cases in which parental samples were available. An analysis of data from individuals with NEDBEH suggests that point mutations affecting the Atrophin-1 domain of RERE are associated with an increased risk of structural eye defects, congenital heart defects, renal anomalies, and sensorineural hearing loss when compared with loss-of-function variants that are likely to lead to haploinsufficiency. A high percentage of RERE pathogenic variants affect a histidine-rich region in the Atrophin-1 domain. We have also identified a recurrent two-amino-acid duplication in this region that is associated with the development of a CHARGE syndrome-like phenotype. We conclude that mutations affecting RERE result in a spectrum of clinical phenotypes. Genotype-phenotype correlations exist and can be used to guide medical decision making. Consideration should also be given to screening for RERE variants in individuals who fulfill diagnostic criteria for CHARGE syndrome but do not carry pathogenic variants in CHD7. © 2018 Wiley Periodicals, Inc.

XGAP: a uniform and extensible data model and software platform for genotype and phenotype experiments

PubMed Central

2010-01-01

We present an extensible software model for the genotype and phenotype community, XGAP. Readers can download a standard XGAP (http://www.xgap.org) or auto-generate a custom version using MOLGENIS with programming interfaces to R-software and web-services or user interfaces for biologists. XGAP has simple load formats for any type of genotype, epigenotype, transcript, protein, metabolite or other phenotype data. Current functionality includes tools ranging from eQTL analysis in mouse to genome-wide association studies in humans. PMID:20214801

XGAP: a uniform and extensible data model and software platform for genotype and phenotype experiments.

PubMed

Swertz, Morris A; Velde, K Joeri van der; Tesson, Bruno M; Scheltema, Richard A; Arends, Danny; Vera, Gonzalo; Alberts, Rudi; Dijkstra, Martijn; Schofield, Paul; Schughart, Klaus; Hancock, John M; Smedley, Damian; Wolstencroft, Katy; Goble, Carole; de Brock, Engbert O; Jones, Andrew R; Parkinson, Helen E; Jansen, Ritsert C

2010-01-01

We present an extensible software model for the genotype and phenotype community, XGAP. Readers can download a standard XGAP (http://www.xgap.org) or auto-generate a custom version using MOLGENIS with programming interfaces to R-software and web-services or user interfaces for biologists. XGAP has simple load formats for any type of genotype, epigenotype, transcript, protein, metabolite or other phenotype data. Current functionality includes tools ranging from eQTL analysis in mouse to genome-wide association studies in humans.

Genetic diversity in Trichomonas vaginalis.

PubMed

Meade, John C; Carlton, Jane M

2013-09-01

Recent advances in genetic characterisation of Trichomonas vaginalis isolates show that the extensive clinical variability in trichomoniasis and its disease sequelae are matched by significant genetic diversity in the organism itself, suggesting a connection between the genetic identity of isolates and their clinical manifestations. Indeed, a high degree of genetic heterogeneity in T vaginalis isolates has been observed using multiple genotyping techniques. A unique two-type population structure that is both local and global in distribution has been identified, and there is evidence of recombination within each group, although sexual recombination between the groups appears to be constrained. There is conflicting evidence in these studies for correlations between T vaginalis genetic identity and clinical presentation, metronidazole susceptibility, and the presence of T vaginalis virus, underscoring the need for adoption of a common standard for genotyping the parasite. Moving forward, microsatellite genotyping and multilocus sequence typing are the most robust techniques for future investigations of T vaginalis genotype-phenotype associations.

Genome-Enabled Estimates of Additive and Nonadditive Genetic Variances and Prediction of Apple Phenotypes Across Environments

PubMed Central

Kumar, Satish; Molloy, Claire; Muñoz, Patricio; Daetwyler, Hans; Chagné, David; Volz, Richard

2015-01-01

The nonadditive genetic effects may have an important contribution to total genetic variation of phenotypes, so estimates of both the additive and nonadditive effects are desirable for breeding and selection purposes. Our main objectives were to: estimate additive, dominance and epistatic variances of apple (Malus × domestica Borkh.) phenotypes using relationship matrices constructed from genome-wide dense single nucleotide polymorphism (SNP) markers; and compare the accuracy of genomic predictions using genomic best linear unbiased prediction models with or without including nonadditive genetic effects. A set of 247 clonally replicated individuals was assessed for six fruit quality traits at two sites, and also genotyped using an Illumina 8K SNP array. Across several fruit quality traits, the additive, dominance, and epistatic effects contributed about 30%, 16%, and 19%, respectively, to the total phenotypic variance. Models ignoring nonadditive components yielded upwardly biased estimates of additive variance (heritability) for all traits in this study. The accuracy of genomic predicted genetic values (GEGV) varied from about 0.15 to 0.35 for various traits, and these were almost identical for models with or without including nonadditive effects. However, models including nonadditive genetic effects further reduced the bias of GEGV. Between-site genotypic correlations were high (>0.85) for all traits, and genotype-site interaction accounted for <10% of the phenotypic variability. The accuracy of prediction, when the validation set was present only at one site, was generally similar for both sites, and varied from about 0.50 to 0.85. The prediction accuracies were strongly influenced by trait heritability, and genetic relatedness between the training and validation families. PMID:26497141

A European multi-centre External Quality Assessment (EQA) study on phenotypic and genotypic methods used for Herpes Simplex Virus (HSV) drug resistance testing.

PubMed

Afshar, Baharak; Bibby, David F; Piorkowska, Renata; Ohemeng-Kumi, Natasha; Snoeck, Robert; Andrei, Graciela; Gillemot, Sarah; Morfin, Florence; Frobert, Emilie; Burrel, Sonia; Boutolleau, David; Crowley, Brendan; Mbisa, Jean L

2017-11-01

Herpes Simplex Virus (HSV) drug resistance is a significant public health concern among immunocompromised individuals. Phenotypic assays are considered the gold standard method for detecting HSV drug resistance. However, plaque reduction assays (PRAs) are technically demanding, often with long turnaround times of up to four weeks. In contrast, genotypic tests can be performed within a few days. The development and coordination of the first European External Quality Assessment (EQA) study to evaluate phenotypic and genotypic methods used for HSV drug resistance testing in specialised reference laboratories. Four HSV-1 or HSV-2 strains with different antiviral susceptibility profiles were isolated from clinical samples. Isolates were quantified by qPCR, and aliquoted in culture medium. One isolate was distributed at two dilutions to help assess assay sensitivity. The panel was distributed to five European centres with a six-week deadline for the return of phenotypic and genotypic results, together with clinical reports. Four out of five participating labs returned results by the deadline. Limited results were later available from the fifth lab. Phenotypic and genotypic data were largely, but not completely, concordant. An unusual resistance profile shown by one of the samples was explained by the detection of a mixed virus population after extensive further investigation by one of the centres. Discordant clinical outputs reflecting the diversity of phenotypic methodologies demonstrated the utility of this exercise. With emerging genotypic technologies looking to supplant phenotyping, there is a need for curated public databases, accessible interpretation tools and standardised control materials for quality management. By establishing a network of testing laboratories, we hope that this EQA scheme will facilitate ongoing progress in this area. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Dystonia Genotype-Phenotype Correlation

ClinicalTrials.gov

2018-04-24

Dystonia; Dystonia; Idiopathic; Dystonia, Primary; Dystonia, Secondary; Dystonia, Familial; Dystonia Disorder; Dystonias, Sporadic; Dystonia; Orofacial; Dystonia Lenticularis; Dystonia, Paroxysmal; Dystonia 6; Dystonia 5; Dystonia 8; Dystonia 9; Dystonia 19; Dystonia 10; Dystonia 11; Dystonia 20; Dystonia 12; Dystonia, Focal; Dystonia of Head; Dystonia, Diurnal

Dystonia: an update on phenomenology, classification, pathogenesis and treatment.

PubMed

Balint, Bettina; Bhatia, Kailash P

2014-08-01

This article will highlight recent advances in dystonia with focus on clinical aspects such as the new classification, syndromic approach, new gene discoveries and genotype-phenotype correlations. Broadening of phenotype of some of the previously described hereditary dystonias and environmental risk factors and trends in treatment will be covered. Based on phenomenology, a new consensus update on the definition, phenomenology and classification of dystonia and a syndromic approach to guide diagnosis have been proposed. Terminology has changed and 'isolated dystonia' is used wherein dystonia is the only motor feature apart from tremor, and the previously called heredodegenerative dystonias and dystonia plus syndromes are now subsumed under 'combined dystonia'. The recently discovered genes ANO3, GNAL and CIZ1 appear not to be a common cause of adult-onset cervical dystonia. Clinical and genetic heterogeneity underlie myoclonus-dystonia, dopa-responsive dystonia and deafness-dystonia syndrome. ALS2 gene mutations are a newly recognized cause for combined dystonia. The phenotypic and genotypic spectra of ATP1A3 mutations have considerably broadened. Two new genome-wide association studies identified new candidate genes. A retrospective analysis suggested complicated vaginal delivery as a modifying risk factor in DYT1. Recent studies confirm lasting therapeutic effects of deep brain stimulation in isolated dystonia, good treatment response in myoclonus-dystonia, and suggest that early treatment correlates with a better outcome. Phenotypic classification continues to be important to recognize particular forms of dystonia and this includes syndromic associations. There are a number of genes underlying isolated or combined dystonia and there will be further new discoveries with the advances in genetic technologies such as exome and whole-genome sequencing. The identification of new genes will facilitate better elucidation of pathogenetic mechanisms and possible corrective therapies.

Selection against canine hip dysplasia: success or failure?

PubMed

Wilson, Bethany; Nicholas, Frank W; Thomson, Peter C

2011-08-01

Canine hip dysplasia (CHD) is a multifactorial skeletal disorder which is very common in pedigree dogs and represents a huge concern for canine welfare. Control schemes based on selective breeding have been in operation for decades. The aim of these schemes is to reduce the impact of CHD on canine welfare by selecting for reduced radiographic evidence of CHD pathology as assessed by a variety of phenotypes. There is less information regarding the genotypic correlation between these phenotypes and the impact of CHD on canine welfare. Although the phenotypes chosen as the basis for these control schemes have displayed heritable phenotypic variation in many studies, success in achieving improvement in the phenotypes has been mixed. There is significant room for improvement in the current schemes through the use of estimated breeding values (EBVs), which can combine a dog's CHD phenotype with CHD phenotypes of relatives, other phenotypes as they are proven to be genetically correlated with CHD (especially elbow dysplasia phenotypes), and information from genetic tests for population-relevant DNA markers, as such tests become available. Additionally, breed clubs should be encouraged and assisted to formulate rational, evidenced-based breeding recommendations for CHD which suit their individual circumstances and dynamically to adjust the breeding recommendations based on continuous tracking of CHD genetic trends. These improvements can assist in safely and effectively reducing the impact of CHD on pedigree dog welfare. Copyright © 2011 Elsevier Ltd. All rights reserved.

A homozygous PMS2 founder mutation with an attenuated constitutional mismatch repair deficiency phenotype.

PubMed

Li, Lili; Hamel, Nancy; Baker, Kristi; McGuffin, Michael J; Couillard, Martin; Gologan, Adrian; Marcus, Victoria A; Chodirker, Bernard; Chudley, Albert; Stefanovici, Camelia; Durandy, Anne; Hegele, Robert A; Feng, Bing-Jian; Goldgar, David E; Zhu, Jun; De Rosa, Marina; Gruber, Stephen B; Wimmer, Katharina; Young, Barbara; Chong, George; Tischkowitz, Marc D; Foulkes, William D

2015-05-01

Inherited mutations in DNA mismatch repair genes predispose to different cancer syndromes depending on whether they are mono-allelic or bi-allelic. This supports a causal relationship between expression level in the germline and phenotype variation. As a model to study this relationship, our study aimed to define the pathogenic characteristics of a recurrent homozygous coding variant in PMS2 displaying an attenuated phenotype identified by clinical genetic testing in seven Inuit families from Northern Quebec. Pathogenic characteristics of the PMS2 mutation NM_000535.5:c.2002A>G were studied using genotype-phenotype correlation, single-molecule expression detection and single genome microsatellite instability analysis. This PMS2 mutation generates a de novo splice site that competes with the authentic site. In homozygotes, expression of the full-length protein is reduced to a level barely detectable by conventional diagnostics. Median age at primary cancer diagnosis is 22 years among 13 NM_000535.5:c.2002A>G homozygotes, versus 8 years in individuals carrying bi-allelic truncating mutations. Residual expression of full-length PMS2 transcript was detected in normal tissues from homozygotes with cancers in their 20s. Our genotype-phenotype study of c.2002A>G illustrates that an extremely low level of PMS2 expression likely delays cancer onset, a feature that could be exploited in cancer preventive intervention. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Phenotype, genotype and gender identity in a large cohort of patients from India with 5α-reductase 2 deficiency.

PubMed

Shabir, I; Khurana, M L; Joseph, A A; Eunice, M; Mehta, M; Ammini, A C

2015-11-01

Deficiency of the 5α-reductase 2 enzyme impairs the conversion of testosterone to dihydrotestosterone (DHT) and differentiation of external genitalia, seminal vesicles and prostate in males. The present study describes the phenotype, genotype and gender identity in a large cohort of patients with 5αRD2. All patients underwent detailed clinical evaluation, hormonal profile, karyotyping and molecular analysis of the SRD5A2 gene. The molecular analysis of the SRD5A2 gene showed the presence of mutant alleles in 24 patients. We found 6 novel mutations IVS(1-2) T>C, p.A52T, 188-189insTA, 904-905ins A, p.A12T and p.E57X in our patients. All patients had ambiguous genitalia and the degrees of under-virilization ranged from penoscrotal hypospadias and microphallus to clitoromegaly. The position of gonads was variable in patients with same mutation. All the patients with mutations in the SRD5A2 gene had male gender identity. Those reared as female had gender dysphoria and underwent gender reassignment. Though a specific genotype-phenotype correlation could not be established in our patient but confirming the diagnosis of 5αRD2 with assessment of the SRD5A2 gene may help in appropriate gender assignment. © 2015 American Society of Andrology and European Academy of Andrology.

Genetic polymorphism of UDP-glucuronosyltransferase (UGT2B15) and glucuronidation of paracetamol in healthy population.

PubMed

Mehboob, Huma; Iqbal, Tahira; Jamil, Amer; Khaliq, Tanweer

2016-05-01

Inter individual variability in polymorphic UDP-glucuronosyltransferase (UGT2B15) has been associated with varied glucuronidation level. The present project was designed to determine the genetic polymorphism of UDP-glucuronosyltransferase (UGT2B15) and glucuronidation of paracetamol in healthy (male=59 and female=50) population. The association between genotype (UGT2B15) and phenotype (paracetamol glucuronidation) has been evaluated. According to trimodal model, genotypes and phenotypes were categorized as fast, intermediate and slow glucuronidators. Presence of wild type allele illustrated a UGT2B15 genotype as fast glucuronidator. The glucuronidation status was investigated by HPLC analysis of paracetamol. Ratio of paracetamol glucuronide to paracetamol was determined with two antimodes at glucuronidation ratio of 0.3 and 1.8. In our study, 7% and 12% of population was distributed as slow glucuronidators by phenotype and genotype, respectively and association between phenotype and genotype was good for analysis of glucuronidation status as displayed by kappa value (0.792).

MinION Nanopore Sequencing Enables Correlation between Resistome Phenotype and Genotype of Coliform Bacteria in Municipal Sewage.

PubMed

Xia, Yu; Li, An-Dong; Deng, Yu; Jiang, Xiao-Tao; Li, Li-Guan; Zhang, Tong

2017-01-01

Wastewater treatment plants (WWTPs) functioned as the intersection between the human society and nature environment, are receiving increasingly more attention on risk assessment of the acquisition of environmental antibiotic resistance genes (ARGs) by pathogenetic populations during treatment. However, because of the general lack of robust resistome profiling methods, genotype, and resistance phenotype is still poorly correlated in human pathogens of sewage samples. Here we applied MinION sequencing to quantify the resistance genes of multiple antibiotic resistant (MAR) coliform bacteria, a common indicator for human enteric pathogens in sewage samples. Our pipeline could deliver the results within 30 h from sample collection and the resistome quantification was consistent to that based on the Illumina platform. Additionally, the long nanopore reads not only enabled a simultaneous identification of the carrier populations of ARGs detected, but also facilitated the genome reconstruction of a representative MAR strain, from which we identified an instance of chromosomal integration of environmental resistance gene obtained by plasmid exchange with a porcine pathogen. This study demonstrated the utilization of MinION sequencing in quick monitoring and simultaneous phylogenetic tracking of environmental ARGs to address potential health risk associated with them.

MinION Nanopore Sequencing Enables Correlation between Resistome Phenotype and Genotype of Coliform Bacteria in Municipal Sewage

PubMed Central

Xia, Yu; Li, An-Dong; Deng, Yu; Jiang, Xiao-Tao; Li, Li-Guan; Zhang, Tong

2017-01-01

Wastewater treatment plants (WWTPs) functioned as the intersection between the human society and nature environment, are receiving increasingly more attention on risk assessment of the acquisition of environmental antibiotic resistance genes (ARGs) by pathogenetic populations during treatment. However, because of the general lack of robust resistome profiling methods, genotype, and resistance phenotype is still poorly correlated in human pathogens of sewage samples. Here we applied MinION sequencing to quantify the resistance genes of multiple antibiotic resistant (MAR) coliform bacteria, a common indicator for human enteric pathogens in sewage samples. Our pipeline could deliver the results within 30 h from sample collection and the resistome quantification was consistent to that based on the Illumina platform. Additionally, the long nanopore reads not only enabled a simultaneous identification of the carrier populations of ARGs detected, but also facilitated the genome reconstruction of a representative MAR strain, from which we identified an instance of chromosomal integration of environmental resistance gene obtained by plasmid exchange with a porcine pathogen. This study demonstrated the utilization of MinION sequencing in quick monitoring and simultaneous phylogenetic tracking of environmental ARGs to address potential health risk associated with them. PMID:29163399

Phenotype-genotype correlations in X linked retinitis pigmentosa.

PubMed Central

Kaplan, J; Pelet, A; Martin, C; Delrieu, O; Aymé, S; Bonneau, D; Briard, M L; Hanauer, A; Larget-Piet, L; Lefrançois, P

1992-01-01

Retinitis pigmentosa (RP) represents a group of clinically heterogeneous retinal degenerations in which all modes of inheritance have been described. We have previously found two different clinical profiles in X linked RP as a function of age and mode of onset. The first clinical form has very early onset with severe myopia. The second form starts later with night blindness with mild myopia or none. At least two genes have been identified in X linked forms, namely RP2 (linked to DXS7, DXS255, and DXS14) and RP3 (linked to DXS84 and OTC) on the short arm of the X chromosome. In order to contribute to phenotype-genotype correlations in X linked RP, we tested the hypothesis that the two clinical profiles could be accounted for by the two different gene loci. The present study provides evidence for linkage of the clinical form with early myopia as the onset symptom with the RP2 gene (pairwise linkage to DXS255: Z = 3.13 at theta = 0), while the clinical form with later night blindness as the onset symptom is linked to the RP3 gene (pairwise linkage to OTC: Z = 4.16 at theta = 0). Images PMID:1357178

Strategy and model building in the fourth dimension: a null model for genotype x age interaction as a Gaussian stationary stochastic process.

PubMed

Diego, Vincent P; Almasy, Laura; Dyer, Thomas D; Soler, Júlia M P; Blangero, John

2003-12-31

Using univariate and multivariate variance components linkage analysis methods, we studied possible genotype x age interaction in cardiovascular phenotypes related to the aging process from the Framingham Heart Study. We found evidence for genotype x age interaction for fasting glucose and systolic blood pressure. There is polygenic genotype x age interaction for fasting glucose and systolic blood pressure and quantitative trait locus x age interaction for a linkage signal for systolic blood pressure phenotypes located on chromosome 17 at 67 cM.

Are "functionally related polymorphisms" of renin-angiotensin-aldosterone system gene polymorphisms associated with hypertension?

PubMed

Hahntow, Ines N; Mairuhu, Gideon; van Valkengoed, Irene Gm; Koopmans, Richard P; Michel, Martin C

2010-06-02

Genotype-phenotype association studies are typically based upon polymorphisms or haplotypes comprised of multiple polymorphisms within a single gene. It has been proposed that combinations of polymorphisms in distinct genes, which functionally impact the same phenotype, may have stronger phenotype associations than those within a single gene. We have tested this hypothesis using genes encoding components of the renin-angiotensin-aldosterone system and the high blood pressure phenotype. Our analysis is based on 1379 participants of the cross-sectional SUNSET study randomly selected from the population register of Amsterdam. Each subject was genotyped for the angiotensinogen M235T, the angiotensin-converting enzyme insertion/deletion and the angiotensin II type 1 receptor A1166C polymorphism. The phenotype high blood pressure was defined either as a categorical variable comparing hypertension versus normotension as in most previous studies or as a continuous variable using systolic, diastolic and mean blood pressure in a multiple regression analysis with gender, ethnicity, age, body-mass-index and antihypertensive medication as covariates. Genotype-phenotype relationships were explored for each polymorphism in isolation and for double and triple polymorphism combinations. At the single polymorphism level, only the A allele of the angiotensin II type 1 receptor was associated with a high blood pressure phenotype. Using combinations of polymorphisms of two or all three genes did not yield stronger/more consistent associations. We conclude that combinations of physiologically related polymorphisms of multiple genes, at least with regard to the renin-angiotensin-aldosterone system and the hypertensive phenotype, do not necessarily offer additional benefit in analyzing genotype/phenotype associations.

Investigation of the Influence of Leaf Thickness on Canopy Reflectance and Physiological Traits in Upland and Pima Cotton Populations

PubMed Central

Pauli, Duke; White, Jeffrey W.; Andrade-Sanchez, Pedro; Conley, Matthew M.; Heun, John; Thorp, Kelly R.; French, Andrew N.; Hunsaker, Douglas J.; Carmo-Silva, Elizabete; Wang, Guangyao; Gore, Michael A.

2017-01-01

Many systems for field-based, high-throughput phenotyping (FB-HTP) quantify and characterize the reflected radiation from the crop canopy to derive phenotypes, as well as infer plant function and health status. However, given the technology's nascent status, it remains unknown how biophysical and physiological properties of the plant canopy impact downstream interpretation and application of canopy reflectance data. In that light, we assessed relationships between leaf thickness and several canopy-associated traits, including normalized difference vegetation index (NDVI), which was collected via active reflectance sensors carried on a mobile FB-HTP system, carbon isotope discrimination (CID), and chlorophyll content. To investigate the relationships among traits, two distinct cotton populations, an upland (Gossypium hirsutum L.) recombinant inbred line (RIL) population of 95 lines and a Pima (G. barbadense L.) population composed of 25 diverse cultivars, were evaluated under contrasting irrigation regimes, water-limited (WL) and well-watered (WW) conditions, across 3 years. We detected four quantitative trait loci (QTL) and significant variation in both populations for leaf thickness among genotypes as well as high estimates of broad-sense heritability (on average, above 0.7 for both populations), indicating a strong genetic basis for leaf thickness. Strong phenotypic correlations (maximum r = −0.73) were observed between leaf thickness and NDVI in the Pima population, but not the RIL population. Additionally, estimated genotypic correlations within the RIL population for leaf thickness with CID, chlorophyll content, and nitrogen discrimination (r^gij = −0.32, 0.48, and 0.40, respectively) were all significant under WW but not WL conditions. Economically important fiber quality traits did not exhibit significant phenotypic or genotypic correlations with canopy traits. Overall, our results support considering variation in leaf thickness as a potential contributing factor to variation in NDVI or other canopy traits measured via proximal sensing, and as a trait that impacts fundamental physiological responses of plants. PMID:28868055

Ion Channel Genes and Epilepsy: Functional Alteration, Pathogenic Potential, and Mechanism of Epilepsy.

PubMed

Wei, Feng; Yan, Li-Min; Su, Tao; He, Na; Lin, Zhi-Jian; Wang, Jie; Shi, Yi-Wu; Yi, Yong-Hong; Liao, Wei-Ping

2017-08-01

Ion channels are crucial in the generation and modulation of excitability in the nervous system and have been implicated in human epilepsy. Forty-one epilepsy-associated ion channel genes and their mutations are systematically reviewed. In this paper, we analyzed the genotypes, functional alterations (funotypes), and phenotypes of these mutations. Eleven genes featured loss-of-function mutations and six had gain-of-function mutations. Nine genes displayed diversified funotypes, among which a distinct funotype-phenotype correlation was found in SCN1A. These data suggest that the funotype is an essential consideration in evaluating the pathogenicity of mutations and a distinct funotype or funotype-phenotype correlation helps to define the pathogenic potential of a gene.

Tree rings provide a new class of phenotypes for genetic associations that foster insights into adaptation of conifers to climate change.

PubMed

Housset, Johann M; Nadeau, Simon; Isabel, Nathalie; Depardieu, Claire; Duchesne, Isabelle; Lenz, Patrick; Girardin, Martin P

2018-04-01

Local adaptation in tree species has been documented through a long history of common garden experiments where functional traits (height, bud phenology) are used as proxies for fitness. However, the ability to identify genes or genomic regions related to adaptation to climate requires the evaluation of traits that precisely reflect how and when climate exerts selective constraints. We combine dendroecology with association genetics to establish a link between genotypes, phenotypes and interannual climatic fluctuations. We illustrate this approach by examining individual tree responses embedded in the annual rings of 233 Pinus strobus trees growing in a common garden experiment representing 38 populations from the majority of its range. We found that interannual variability in growth was affected by low temperatures during spring and autumn, and by summer heat and drought. Among-population variation in climatic sensitivity was significantly correlated with the mean annual temperature of the provenance, suggesting local adaptation. Genotype-phenotype associations using these new tree-ring phenotypes validated nine candidate genes identified in a previous genetic-environment association study. Combining dendroecology with association genetics allowed us to assess tree vulnerability to past climate at fine temporal scales and provides avenues for future genomic studies on functional adaptation in forest trees. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

AFLP-based genetic diversity and its comparison with diversity based on SSR, SAMPL, and phenotypic traits in bread wheat.

PubMed

Roy, J K; Lakshmikumaran, M S; Balyan, H S; Gupta, P K

2004-02-01

Data on AFLP (eight primer pairs) and 14 phenotypic traits, collected on 55 elite and exotic bread wheat genotypes, were utilized for estimations of genetic diversity. We earlier used these 55 genotypes for a similar study using SSRs and SAMPL. As many as 615 scorable AFLP bands visualized included 287 (46.6%) polymorphic bands. The phenotypic traits included yield and its component traits, as well as physiomorphological traits like flag leaf area. Dendrograms were prepared using cluster analysis based on Jaccard's similarity coefficients in case of AFLP and on squared Euclidean distances in case of phenotypic traits. PCA was conducted using AFLP data and a PCA plot was prepared, which was compared with clustering patterns in two dendrograms, one each for AFLP and phenotypic traits. The results were also compared with published results that included studies conducted elsewhere using entirely different wheat germplasm and our own SSR and SAMPL studies based on the same 55 genotypes used in the present study. It was shown that molecular markers are superior to phenotypic traits and that AFLP and SAMPL are superior to other molecular markers for estimation of genetic diversity. On the basis of AFLP analysis and keeping in view the yield performance and stability, a pair of genotypes (E3876 and E677) was recommended for hybridization in order to develop superior cultivars.

Evolution on neutral networks accelerates the ticking rate of the molecular clock.

PubMed

Manrubia, Susanna; Cuesta, José A

2015-01-06

Large sets of genotypes give rise to the same phenotype, because phenotypic expression is highly redundant. Accordingly, a population can accept mutations without altering its phenotype, as long as the genotype mutates into another one on the same set. By linking every pair of genotypes that are mutually accessible through mutation, genotypes organize themselves into neutral networks (NNs). These networks are known to be heterogeneous and assortative, and these properties affect the evolutionary dynamics of the population. By studying the dynamics of populations on NNs with arbitrary topology, we analyse the effect of assortativity, of NN (phenotype) fitness and of network size. We find that the probability that the population leaves the network is smaller the longer the time spent on it. This progressive 'phenotypic entrapment' entails a systematic increase in the overdispersion of the process with time and an acceleration in the fixation rate of neutral mutations. We also quantify the variation of these effects with the size of the phenotype and with its fitness relative to that of neighbouring alternatives. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Evolution on neutral networks accelerates the ticking rate of the molecular clock

PubMed Central

Manrubia, Susanna; Cuesta, José A.

2015-01-01

Large sets of genotypes give rise to the same phenotype, because phenotypic expression is highly redundant. Accordingly, a population can accept mutations without altering its phenotype, as long as the genotype mutates into another one on the same set. By linking every pair of genotypes that are mutually accessible through mutation, genotypes organize themselves into neutral networks (NNs). These networks are known to be heterogeneous and assortative, and these properties affect the evolutionary dynamics of the population. By studying the dynamics of populations on NNs with arbitrary topology, we analyse the effect of assortativity, of NN (phenotype) fitness and of network size. We find that the probability that the population leaves the network is smaller the longer the time spent on it. This progressive ‘phenotypic entrapment’ entails a systematic increase in the overdispersion of the process with time and an acceleration in the fixation rate of neutral mutations. We also quantify the variation of these effects with the size of the phenotype and with its fitness relative to that of neighbouring alternatives. PMID:25392402

WGS accurately predicts antimicrobial resistance in Escherichia coli

USDA-ARS?s Scientific Manuscript database

Objectives: To determine the effectiveness of whole-genome sequencing (WGS) in identifying resistance genotypes of multidrug-resistant Escherichia coli (E. coli) and whether these correlate with observed phenotypes. Methods: Seventy-six E. coli strains were isolated from farm cattle and measured f...

Targeted next-generation sequencing reveals novel USH2A mutations associated with diverse disease phenotypes: implications for clinical and molecular diagnosis.

PubMed

Chen, Xue; Sheng, Xunlun; Liu, Xiaoxing; Li, Huiping; Liu, Yani; Rong, Weining; Ha, Shaoping; Liu, Wenzhou; Kang, Xiaoli; Zhao, Kanxing; Zhao, Chen

2014-01-01

USH2A mutations have been implicated in the disease etiology of several inherited diseases, including Usher syndrome type 2 (USH2), nonsyndromic retinitis pigmentosa (RP), and nonsyndromic deafness. The complex genetic and phenotypic spectrums relevant to USH2A defects make it difficult to manage patients with such mutations. In the present study, we aim to determine the genetic etiology and to characterize the correlated clinical phenotypes for three Chinese pedigrees with nonsyndromic RP, one with RP sine pigmento (RPSP), and one with USH2. Family histories and clinical details for all included patients were reviewed. Ophthalmic examinations included best corrected visual acuities, visual field measurements, funduscopy, and electroretinography. Targeted next-generation sequencing (NGS) was applied using two sequence capture arrays to reveal the disease causative mutations for each family. Genotype-phenotype correlations were also annotated. Seven USH2A mutations, including four missense substitutions (p.P2762A, p.G3320C, p.R3719H, and p.G4763R), two splice site variants (c.8223+1G>A and c.8559-2T>C), and a nonsense mutation (p.Y3745*), were identified as disease causative in the five investigated families, of which three reported to have consanguineous marriage. Among all seven mutations, six were novel, and one was recurrent. Two homozygous missense mutations (p.P2762A and p.G3320C) were found in one individual family suggesting a potential double hit effect. Significant phenotypic divergences were revealed among the five families. Three families of the five families were affected with early, moderated, or late onset RP, one with RPSP, and the other one with USH2. Our study expands the genotypic and phenotypic variability relevant to USH2A mutations, which would help with a clear insight into the complex genetic and phenotypic spectrums relevant to USH2A defects, and is complementary for a better management of patients with such mutations. We have also demonstrated that a targeted NGS approach is a valuable tool for the genetic diagnosis of USH2 and RP.

Targeted Next-Generation Sequencing Reveals Novel USH2A Mutations Associated with Diverse Disease Phenotypes: Implications for Clinical and Molecular Diagnosis

PubMed Central

Li, Huiping; Liu, Yani; Rong, Weining; Ha, Shaoping; Liu, Wenzhou; Kang, Xiaoli; Zhao, Kanxing; Zhao, Chen

2014-01-01

USH2A mutations have been implicated in the disease etiology of several inherited diseases, including Usher syndrome type 2 (USH2), nonsyndromic retinitis pigmentosa (RP), and nonsyndromic deafness. The complex genetic and phenotypic spectrums relevant to USH2A defects make it difficult to manage patients with such mutations. In the present study, we aim to determine the genetic etiology and to characterize the correlated clinical phenotypes for three Chinese pedigrees with nonsyndromic RP, one with RP sine pigmento (RPSP), and one with USH2. Family histories and clinical details for all included patients were reviewed. Ophthalmic examinations included best corrected visual acuities, visual field measurements, funduscopy, and electroretinography. Targeted next-generation sequencing (NGS) was applied using two sequence capture arrays to reveal the disease causative mutations for each family. Genotype-phenotype correlations were also annotated. Seven USH2A mutations, including four missense substitutions (p.P2762A, p.G3320C, p.R3719H, and p.G4763R), two splice site variants (c.8223+1G>A and c.8559-2T>C), and a nonsense mutation (p.Y3745*), were identified as disease causative in the five investigated families, of which three reported to have consanguineous marriage. Among all seven mutations, six were novel, and one was recurrent. Two homozygous missense mutations (p.P2762A and p.G3320C) were found in one individual family suggesting a potential double hit effect. Significant phenotypic divergences were revealed among the five families. Three families of the five families were affected with early, moderated, or late onset RP, one with RPSP, and the other one with USH2. Our study expands the genotypic and phenotypic variability relevant to USH2A mutations, which would help with a clear insight into the complex genetic and phenotypic spectrums relevant to USH2A defects, and is complementary for a better management of patients with such mutations. We have also demonstrated that a targeted NGS approach is a valuable tool for the genetic diagnosis of USH2 and RP. PMID:25133613

Type II Gaucher disease: compound heterozygote with RecNciI and L444P mutations.

PubMed

Lee, Y S; Poh, L K; Ida, H; Loke, K Y

2001-04-01

We report the phenotype and genotype of an Indonesian Chinese boy with type II Gaucher disease. He had a unique presentation of recurrent cyanosis from laryngospasm. He was compound heterozygous for L444P/L444P + A456P + V460V. There have been few reports of this heterozygosity and its phenoptype. This genotype-phenotype correlation will be important for physicians in genetic counselling. Type II Gaucher disease in Southeast Asia may not be as rare as was perceived, but may be a condition that is under-reported. The success of our technique together with the results have made it possible for us to perform prenatal diagnosis and carrier detection for the family.

PON1-192 phenotype and genotype assessments in 918 subjects of the Stanislas cohort study.

PubMed

Vincent-Viry, Monique; Sass, Catherine; Bastien, Sabine; Aguillon, Dominique; Siest, Gérard; Visvikis, Sophie

2003-04-01

This study describes the factors of variation of the enzymes related to the PON1-192 phenotype assessment, i.e., basal paraoxonase, salt-stimulated paraoxonase and arylesterase activities, and compares the PON1-192 phenotype to the PON1-192 genotype assessments in supposedly healthy subjects issued from the Stanislas cohort study. The studied population included 918 subjects, i.e., 221 families including 441 adults and 477 children aged 4 to 58 years. Potential determinants such as age, gender, body mass index, alcohol and tobacco consumption, and oral contraceptive intake have been studied. The PON ratio (salt-stimulated paraoxonase/arylesterase) was trimodally distributed and the cut-off values used to differentiate the two homozygous (AA and BB phenotypes) from the heterozygous (AB phenotype) subjects were 3.0 and 7.0 in this study. In males, basal paraoxonase and salt-stimulated paraoxonase activities were not affected by alcohol consumption and current smoking, but basal paraoxonase activity was decreased by 15% by current smoking and was increased by 15% by oral contraceptive intake in females as was the salt-stimulated paraoxonase activity. The level of discordance between phenotype and genotype assessments was 7.2% (66/918). Most of the discrepancies were observed between the BB and AB phenotypes (4.25%).

Genotypic and phenotypic characterization of genetic differentiation and diversity in the USDA rice mini-core collection.

PubMed

Li, Xiaobai; Yan, Wengui; Agrama, Hesham; Hu, Biaolin; Jia, Limeng; Jia, Melissa; Jackson, Aaron; Moldenhauer, Karen; McClung, Anna; Wu, Dianxing

2010-12-01

A rice mini-core collection consisting of 217 accessions has been developed to represent the USDA core and whole collections that include 1,794 and 18,709 accessions, respectively. To improve the efficiency of mining valuable genes and broadening the genetic diversity in breeding, genetic structure and diversity were analyzed using both genotypic (128 molecular markers) and phenotypic (14 numerical traits) data. This mini-core had 13.5 alleles per locus, which is the most among the reported germplasm collections of rice. Similarly, polymorphic information content (PIC) value was 0.71 in the mini-core which is the highest with one exception. The high genetic diversity in the mini-core suggests there is a good possibility of mining genes of interest and selecting parents which will improve food production and quality. A model-based clustering analysis resulted in lowland rice including three groups, aus (39 accessions), indica (71) and their admixtures (5), upland rice including temperate japonica (32), tropical japonica (40), aromatic (6) and their admixtures (12) and wild rice (12) including glaberrima and four other species of Oryza. Group differentiation was analyzed using both genotypic distance Fst from 128 molecular markers and phenotypic (Mahalanobis) distance D(2) from 14 traits. Both dendrograms built by Fst and D(2) reached similar-differentiative relationship among these genetic groups, and the correlation coefficient showed high value 0.85 between Fst matrix and D(2) matrix. The information of genetic and phenotypic differentiation could be helpful for the association mapping of genes of interest. Analysis of genotypic and phenotypic diversity based on genetic structure would facilitate parent selection for broadening genetic base of modern rice cultivars via breeding effort.

The low EOMES/TBX21 molecular phenotype in multiple sclerosis reflects CD56+ cell dysregulation and is affected by immunomodulatory therapies.

PubMed

McKay, Fiona C; Gatt, Prudence N; Fewings, Nicole; Parnell, Grant P; Schibeci, Stephen D; Basuki, Monica A I; Powell, Joseph E; Goldinger, Anita; Fabis-Pedrini, Marzena J; Kermode, Allan G; Burke, Therese; Vucic, Steve; Stewart, Graeme J; Booth, David R

2016-02-01

Multiple Sclerosis (MS) is an autoimmune disease treated by therapies targeting peripheral blood cells. We previously identified that expression of two MS-risk genes, the transcription factors EOMES and TBX21 (ET), was low in blood from MS and stable over time. Here we replicated the low ET expression in a new MS cohort (p<0.0007 for EOMES, p<0.028 for TBX21) and demonstrate longitudinal stability (p<10(-4)) and high heritability (h(2)=0.48 for EOMES) for this molecular phenotype. Genes whose expression correlated with ET, especially those controlling cell migration, further defined the phenotype. CD56+ cells and other subsets expressed lower levels of Eomes or T-bet protein and/or were under-represented in MS. EOMES and TBX21 risk SNP genotypes, and serum EBNA-1 titres were not correlated with ET expression, but HLA-DRB1*1501 genotype was. ET expression was normalised to healthy control levels with natalizumab, and was highly variable for glatiramer acetate, fingolimod, interferon-beta, dimethyl fumarate. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Natural Variation in Elicitation of Defense-Signaling Associates to Field Resistance Against the Spot Blotch Disease in Bread Wheat (Triticum aestivum L.)

PubMed Central

Sharma, Sandeep; Sahu, Ranabir; Navathe, Sudhir; Mishra, Vinod K.; Chand, Ramesh; Singh, Pawan K.; Joshi, Arun K.; Pandey, Shree P.

2018-01-01

Spot blotch, caused by the hemibiotropic fungus Bipolaris sorokiniana, is amongst the most damaging diseases of wheat. Still, natural variation in expression of biochemical traits that determine field resistance to spot blotch in wheat remain unaddressed. To understand how genotypic variations relate to metabolite profiles of the components of defense-signaling and the plant performance, as well as to discover novel sources of resistance against spot blotch, we have conducted field studies using 968 wheat genotypes at 5 geographical locations in South-Asia in 2 years. 46 genotypes were identified as resistant. Further, in independent confirmatory trials in subsequent 3 years, over 5 geographical locations, we re-characterized 55 genotypes for their resistance (above 46 along with Yangmai#6, a well characterized resistant genotype, and eight susceptible genotypes). We next determined time-dependent spot blotch-induced metabolite profiles of components of defense-signaling as well as levels of enzymatic components of defense pathway (such as salicylic acid (SA), phenolic acids, and redox components), and derived co-variation patterns with respect to resistance in these 55 genotypes. Spot blotch-induced SA accumulation was negatively correlated to disease progression. Amongst phenolic acids, syringic acid was most strongly inversely correlated to disease progression, indicating a defensive function, which was independently confirmed. Thus, exploring natural variation proved extremely useful in determining traits influencing phenotypic plasticity and adaptation to complex environments. Further, by overcoming environmental heterogeneity, our study identifies germplasm and biochemical traits that are deployable for spot blotch resistance in wheat along South-Asia. PMID:29868089

Natural Variation in Elicitation of Defense-Signaling Associates to Field Resistance Against the Spot Blotch Disease in Bread Wheat (Triticum aestivum L.).

PubMed

Sharma, Sandeep; Sahu, Ranabir; Navathe, Sudhir; Mishra, Vinod K; Chand, Ramesh; Singh, Pawan K; Joshi, Arun K; Pandey, Shree P

2018-01-01

Spot blotch, caused by the hemibiotropic fungus Bipolaris sorokiniana , is amongst the most damaging diseases of wheat. Still, natural variation in expression of biochemical traits that determine field resistance to spot blotch in wheat remain unaddressed. To understand how genotypic variations relate to metabolite profiles of the components of defense-signaling and the plant performance, as well as to discover novel sources of resistance against spot blotch, we have conducted field studies using 968 wheat genotypes at 5 geographical locations in South-Asia in 2 years. 46 genotypes were identified as resistant. Further, in independent confirmatory trials in subsequent 3 years, over 5 geographical locations, we re-characterized 55 genotypes for their resistance (above 46 along with Yangmai#6, a well characterized resistant genotype, and eight susceptible genotypes). We next determined time-dependent spot blotch-induced metabolite profiles of components of defense-signaling as well as levels of enzymatic components of defense pathway (such as salicylic acid (SA), phenolic acids, and redox components), and derived co-variation patterns with respect to resistance in these 55 genotypes. Spot blotch-induced SA accumulation was negatively correlated to disease progression. Amongst phenolic acids, syringic acid was most strongly inversely correlated to disease progression, indicating a defensive function, which was independently confirmed. Thus, exploring natural variation proved extremely useful in determining traits influencing phenotypic plasticity and adaptation to complex environments. Further, by overcoming environmental heterogeneity, our study identifies germplasm and biochemical traits that are deployable for spot blotch resistance in wheat along South-Asia.

Gaucher disease: Pseudoreversion of a disease mutation`s effects--implications for structure/function and genotype/phenotype correlations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ponce, E.; Mear, J; Grabowski, G.A.

1994-09-01

Numerous mutations ({approximately}45) of the acid {beta}-glucosidase gene have been identified in patients with Gaucher disease. Many of these have been characterized by partial sequencing of cDNAs derived by RT-PCR or PCR of genomic DNA. In addition, genotype/phenotype correlations have been based on screening for known mutations. Thus, only a part of the gene is characterized in any population of affected patients. Several Gaucher disease alleles contain multiple, authentic point mutations that raises concern about conclusions based on only partial genetic characterization. Several wild-type cDNAs for acid {beta}-glucosidase have been sequenced. One contained a cloning artifact encoding R495H. We expressedmore » this cDNA and showed that the R495H enzyme had normal kinetic and stability properties. A disease-associated allele encoding R496H has been found by several groups. The close association and similarities of these two substitutions led us to question the disease casuality of the R496H allele. To evaluate this, we created and/or expressed cDNAs encoding R495, R496 (wild-type), (R495H, R496), (R495, R496H) and (R495H, R496H). The (wild-type) and (R495H, R496) enzymes had indistinguishable properties whereas the (R495, R496H) enzyme was essentially inactive. The introduction of both mutations (R495H, R496H) produced an enzyme whose activity was 25 to 50% of the wild-type. These results indicate that a pseudoreversion to a functional enzyme can occur by introducing a functionally neutral mutation together with a severe mutation. These results have major implications to structure/function and genotype/phenotype correlations in this disease.« less

ADCY5-related dyskinesia: Broader spectrum and genotype-phenotype correlations.

PubMed

Chen, Dong-Hui; Méneret, Aurélie; Friedman, Jennifer R; Korvatska, Olena; Gad, Alona; Bonkowski, Emily S; Stessman, Holly A; Doummar, Diane; Mignot, Cyril; Anheim, Mathieu; Bernes, Saunder; Davis, Marie Y; Damon-Perrière, Nathalie; Degos, Bertrand; Grabli, David; Gras, Domitille; Hisama, Fuki M; Mackenzie, Katherine M; Swanson, Phillip D; Tranchant, Christine; Vidailhet, Marie; Winesett, Steven; Trouillard, Oriane; Amendola, Laura M; Dorschner, Michael O; Weiss, Michael; Eichler, Evan E; Torkamani, Ali; Roze, Emmanuel; Bird, Thomas D; Raskind, Wendy H

2015-12-08

To investigate the clinical spectrum and distinguishing features of adenylate cyclase 5 (ADCY5)-related dyskinesia and genotype-phenotype relationship. We analyzed ADCY5 in patients with choreiform or dystonic movements by exome or targeted sequencing. Suspected mosaicism was confirmed by allele-specific amplification. We evaluated clinical features in our 50 new and previously reported cases. We identified 3 new families and 12 new sporadic cases with ADCY5 mutations. These mutations cause a mixed hyperkinetic disorder that includes dystonia, chorea, and myoclonus, often with facial involvement. The movements are sometimes painful and show episodic worsening on a fluctuating background. Many patients have axial hypotonia. In 2 unrelated families, a p.A726T mutation in the first cytoplasmic domain (C1) causes a relatively mild disorder of prominent facial and hand dystonia and chorea. Mutations p.R418W or p.R418Q in C1, de novo in 13 individuals and inherited in 1, produce a moderate to severe disorder with axial hypotonia, limb hypertonia, paroxysmal nocturnal or diurnal dyskinesia, chorea, myoclonus, and intermittent facial dyskinesia. Somatic mosaicism is usually associated with a less severe phenotype. In one family, a p.M1029K mutation in the C2 domain causes severe dystonia, hypotonia, and chorea. The progenitor, whose childhood-onset episodic movement disorder almost disappeared in adulthood, was mosaic for the mutation. ADCY5-related dyskinesia is a childhood-onset disorder with a wide range of hyperkinetic abnormal movements. Genotype-specific correlations and mosaicism play important roles in the phenotypic variability. Recurrent mutations suggest particular functional importance of residues 418 and 726 in disease pathogenesis. © 2015 American Academy of Neurology.

Phenotype, Genotype, and Drug Resistance in Subtype C HIV-1 Infection.

PubMed

Derache, Anne; Wallis, Carole L; Vardhanabhuti, Saran; Bartlett, John; Kumarasamy, Nagalingeswaran; Katzenstein, David

2016-01-15

Virologic failure in subtype C is characterized by high resistance to first-line antiretroviral (ARV) drugs, including efavirenz, nevirapine, and lamivudine, with nucleoside resistance including type 2 thymidine analog mutations, K65R, a T69del, and M184V. However, genotypic algorithms predicting resistance are mainly based on subtype B viruses and may under- or overestimate drug resistance in non-B subtypes. To explore potential treatment strategies after first-line failure, we compared genotypic and phenotypic susceptibility of subtype C human immunodeficiency virus 1 (HIV-1) following first-line ARV failure. AIDS Clinical Trials Group 5230 evaluated patients failing an initial nonnucleoside reverse-transcriptase inhibitor (NNRTI) regimen in Africa and Asia, comparing the genotypic drug resistance and phenotypic profile from the PhenoSense (Monogram). Site-directed mutagenesis studies of K65R and T69del assessed the phenotypic impact of these mutations. Genotypic algorithms overestimated resistance to etravirine and rilpivirine, misclassifying 28% and 32%, respectively. Despite K65R with the T69del in 9 samples, tenofovir retained activity in >60%. Reversion of the K65R increased susceptibility to tenofovir and other nucleosides, while reversion of the T69del showed increased resistance to zidovudine, with little impact on other NRTI. Although genotype and phenotype were largely concordant for first-line drugs, estimates of genotypic resistance to etravirine and rilpivirine may misclassify subtype C isolates compared to phenotype. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Proteome-wide association studies identify biochemical modules associated with a wing-size phenotype in Drosophila melanogaster.

PubMed

Okada, Hirokazu; Ebhardt, H Alexander; Vonesch, Sibylle Chantal; Aebersold, Ruedi; Hafen, Ernst

2016-09-01

The manner by which genetic diversity within a population generates individual phenotypes is a fundamental question of biology. To advance the understanding of the genotype-phenotype relationships towards the level of biochemical processes, we perform a proteome-wide association study (PWAS) of a complex quantitative phenotype. We quantify the variation of wing imaginal disc proteomes in Drosophila genetic reference panel (DGRP) lines using SWATH mass spectrometry. In spite of the very large genetic variation (1/36 bp) between the lines, proteome variability is surprisingly small, indicating strong molecular resilience of protein expression patterns. Proteins associated with adult wing size form tight co-variation clusters that are enriched in fundamental biochemical processes. Wing size correlates with some basic metabolic functions, positively with glucose metabolism but negatively with mitochondrial respiration and not with ribosome biogenesis. Our study highlights the power of PWAS to filter functional variants from the large genetic variability in natural populations.

Short communication: Genotyping of cows to speed up availability of genomic estimated breeding values for direct health traits in Austrian Fleckvieh (Simmental) cattle--genetic and economic aspects.

PubMed

Egger-Danner, C; Schwarzenbacher, H; Willam, A

2014-07-01

The aim of this study was to quantify the impact of genotyping cows with reliable phenotypes for direct health traits on annual monetary genetic gain (AMGG) and discounted profit. The calculations were based on a deterministic approach using ZPLAN software (University of Hohenheim, Stuttgart, Germany). It was assumed that increases in reliability of the total merit index (TMI) of 5, 15, and 25 percentage points were achieved through genotyping 5,000, 25,000, and 50,000 cows, respectively. Costs for phenotyping, genotyping, and genomic estimated breeding values vary between €150 and €20 per cow. The gain in genotyping cows for traits with medium to high heritability is more than for direct health traits with low heritability. The AMGG is increased by 1.5% if the reliability of TMI is 5 percentage points higher (i.e., 5,000 cows genotyped) and 6.53% higher AMGG can be expected when the reliability of TMI is increased by 25 percentage points (i.e., 50,000 cows genotyped). The discounted profit depends not only on the costs of genotyping but also on the population size. This study indicates that genotyping cows with reliable phenotypes is feasible to speed up the availability of genomic estimated breeding values for direct health traits. But, because of the huge amount of valid phenotypes and genotypes needed to establish an efficient genomic evaluation, it is likely that financial constraints will be the main limiting factor for implementation into breeding program such as Fleckvieh Austria. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A latent modeling approach to genotype-phenotype relationships: maternal problem behavior clusters, prenatal smoking, and MAOA genotype.

PubMed

McGrath, L M; Mustanski, B; Metzger, A; Pine, D S; Kistner-Griffin, E; Cook, E; Wakschlag, L S

2012-08-01

This study illustrates the application of a latent modeling approach to genotype-phenotype relationships and gene × environment interactions, using a novel, multidimensional model of adult female problem behavior, including maternal prenatal smoking. The gene of interest is the monoamine oxidase A (MAOA) gene which has been well studied in relation to antisocial behavior. Participants were adult women (N = 192) who were sampled from a prospective pregnancy cohort of non-Hispanic, white individuals recruited from a neighborhood health clinic. Structural equation modeling was used to model a female problem behavior phenotype, which included conduct problems, substance use, impulsive-sensation seeking, interpersonal aggression, and prenatal smoking. All of the female problem behavior dimensions clustered together strongly, with the exception of prenatal smoking. A main effect of MAOA genotype and a MAOA × physical maltreatment interaction were detected with the Conduct Problems factor. Our phenotypic model showed that prenatal smoking is not simply a marker of other maternal problem behaviors. The risk variant in the MAOA main effect and interaction analyses was the high activity MAOA genotype, which is discrepant from consensus findings in male samples. This result contributes to an emerging literature on sex-specific interaction effects for MAOA.

On the nosology and pathogenesis of Wolf-Hirschhorn syndrome: genotype-phenotype correlation analysis of 80 patients and literature review.

PubMed

Zollino, Marcella; Murdolo, Marina; Marangi, Giuseppe; Pecile, Vanna; Galasso, Cinzia; Mazzanti, Laura; Neri, Giovanni

2008-11-15

Based on genotype-phenotype correlation analysis of 80 Wolf-Hirschhorn syndrome (WHS) patients, as well as on review of relevant literature, we add further insights to the following aspects of WHS: (1) clinical delineation and phenotypic categories; (2) characterization of the basic genomic defect, mechanisms of origin and familiarity; (3) identification of prognostic factors for mental retardation; (4) chromosome mapping of the distinctive clinical signs, in an effort to identify pathogenic genes. Clinically, we consider that minimal diagnostic criteria for WHS, defining a "core" phenotype, are typical facial appearance, mental retardation, growth delay and seizures (or EEG anomalies). Three different categories of the WHS phenotype were defined, generally correlating with the extent of the 4p deletion. The first one comprises a small deletion not exceeding 3.5 Mb, that is usually associated with a mild phenotype, lacking major malformations. This category is likely under-diagnosed. The second and by far the more frequent category is identified by large deletions, averaging between 5 and 18 Mb, and causes the widely recognizable WHS phenotype. The third clinical category results from a very large deletion exceeding 22-25 Mb causing a severe phenotype, that can hardly be defined as typical WHS. Genetically, de novo chromosome abnormalities in WHS include pure deletions but also complex rearrangements, mainly unbalanced translocations. With the exception of t(4p;8p), WHS-associated chromosome abnormalities are neither mediated by segmental duplications, nor associated with a parental inversion polymorphism on 4p16.3. Factors involved in prediction of prognosis include the extent of the deletion, the occurrence of complex chromosome anomalies, and the severity of seizures. We found that the core phenotype maps within the terminal 1.9 Mb region of chromosome 4p. Therefore, WHSCR-2 should be considered the critical region for this condition. We also confirmed that the pathogenesis of WHS is multigenic. Specific and independent chromosome regions were characterized for growth delay and seizures, as well as for the additional clinical signs that characterize this condition. With the exception of parental balanced translocations, familial recurrence is uncommon.

Modification of Multiple Sclerosis Phenotypes by African Ancestry at HLA.

PubMed

Cree, Bruce A C; Reich, David E; Khan, Omar; De Jager, Philip L; Nakashima, Ichiro; Takahashi, Toshiyuki; Bar-Or, Amit; Tong, Christine; Hauser, Stephen L; Oksenberg, Jorge R

2009-02-01

In those with multiple sclerosis (MS), African American individuals have a more severe disease course, an older age at onset, and more often have clinical manifestations restricted to the optic nerves and spinal cord (opticospinal MS) than white persons. To determine whether genetic variation influences clinical MS patterns. Retrospective multicenter cohort study. Six hundred seventy-three African American and 717 white patients with MS. Patients with MS were genotyped for HLA-DRB1 and HLA-DQB1 alleles. The proportion of European ancestry at HLA was estimated by genotyping single-nucleotide polymorphisms with known significant frequency differences in West African and European populations. These genotypes were correlated with the opticospinal disease phenotype, disability measures, and age at onset. Subjects with DRB1*15 alleles were twice as likely to have typical MS rather than opticospinal MS (P = .001). Of the subjects with opticospinal MS or a history of recurrent transverse myelitis who were seropositive for anti-aquaporin 4 antibodies (approximately 5%), none carried DRB1*15 alleles (P = .008). Independently of DRB1*15, African ancestry at HLA correlated with disability as measured by the Multiple Sclerosis Severity Score (P < .001) and risk of cane dependency (hazard ratio, 1.36; P < .001); DRB1*15 alleles were associated with a 2.1-year earlier age at onset (P < .001). These data indicate that the role of HLA in MS is not limited to disease susceptibility but that genes embedded in this locus also influence clinical outcomes.

Growth and psychomotor development of patients with Duchenne muscular dystrophy.

PubMed

Sarrazin, Elisabeth; von der Hagen, Maja; Schara, Ulrike; von Au, Katja; Kaindl, Angela M

2014-01-01

Duchenne muscular dystrophy (DMD) is one of the most common hereditary degenerative neuromuscular diseases and caused by mutations in the dystrophin gene. The objective of the retrospective study was to describe growth and psychomotor development of patients with DMD and to detect a possible genotype-phenotype correlation. Data from 263 patients with DMD (mean age 7.1 years) treated at the Departments of Pediatric Neurology in three German University Hospitals was assessed with respect to body measurements (length, weight, body mass index BMI, head circumference OFC), motor and cognitive development as well as genotype (site of mutation). Anthropometric measures and developmental data were compared to those of a reference population and deviations were analyzed for their frequency in the cohort as well as in relation to the genotypes. Corticosteroid therapy was implemented in 29 from 263 patients. Overall 30% of the patients exhibit a short statue (length < 3rd centile) with onset early in development at 2-5 years of age, and this is even more prevalent when steroid therapy is applied (45% of patients with steroid therapy). The BMI shows a rightwards shift (68% > 50th centile) and the OFC a leftwards shift (65% < 50th centile, 5% microcephaly). Gross motor development is delayed in a third of the patients (mean age at walking 18.3 months, 30% > 18 months, 8% > 24 months). Almost half of the patients show cognitive impairment (26% learning disability, 17% intellectual disability). Although there is no strict genotype-phenotype correlation, particularly mutations in the distal part of the dystrophin gene are frequently associated with short stature and a high rate of microcephaly as well as cognitive impairment. Copyright © 2013 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Monogenic Autoinflammatory Diseases with Mendelian Inheritance: Genes, Mutations, and Genotype/Phenotype Correlations

PubMed Central

Martorana, Davide; Bonatti, Francesco; Mozzoni, Paola; Vaglio, Augusto; Percesepe, Antonio

2017-01-01

Autoinflammatory diseases (AIDs) are a genetically heterogeneous group of diseases caused by mutations of genes encoding proteins, which play a pivotal role in the regulation of the inflammatory response. In the pathogenesis of AIDs, the role of the genetic background is triggered by environmental factors through the modulation of the innate immune system. Monogenic AIDs are characterized by Mendelian inheritance and are caused by highly penetrant genetic variants in single genes. During the last years, remarkable progress has been made in the identification of disease-associated genes by using new technologies, such as next-generation sequencing, which has allowed the genetic characterization in undiagnosed patients and in sporadic cases by means of targeted resequencing of a gene panel and whole exome sequencing. In this review, we delineate the genetics of the monogenic AIDs, report the role of the most common gene mutations, and describe the evidences of the most sound genotype/phenotype correlations in AID. PMID:28421071

Lessons From Paired Data From exPVP Maize Lines in Agronomic Field Trials and RGB And Hyperspectral Time-Series Imaging In Controlled Environments

NASA Astrophysics Data System (ADS)

Schnable, J. C.; Pandey, P.; Ge, Y.; Xu, Y.; Qiu, Y.; Liang, Z.

2017-12-01

Maize Zea mays ssp. mays is one of three crops, along with rice and wheat, responsible for more than 1/2 of all calories consumed around the world. Increasing the yield and stress tolerance of these crops is essential to meet the growing need for food. The cost and speed of plant phenotyping is currently the largest constraint on plant breeding efforts. Datasets linking new types of high throughput phenotyping data collected from plants to the performance of the same genotypes under agronomic conditions across a wide range of environments are essential for developing new statistical approaches and computer vision based tools. A set of maize inbreds and hybrids - primarily recently off patent lines - were phenotyped using a high throughput platform at University of Nebraska-Lincoln. These lines have been previously subjected to high density genotyping, and scored for a core set of 13 phenotypes in field trials across 13 North American states in 2014, 2015, 2016, and 2017. Correlations between image-based measurements and manual measurements demonstrated the feasibility of quantifying variation in plant architecture using image data. However, we demonstrate that naive approaches to measuring traits such as biomass where are developed without integrating genotypic information can introduce nonrandom measurement errors which are confounded with variation between plant accessions. Analysis of hyperspectral image data demonstrated unique signatures from stem tissue which were not identified using aerial imagry. Integrating heritable phenotypes from high-throughput phenotyping data with field data from different environments can reveal previously unknown factors influencing yield plasticity.

Conventional and hyperspectral time-series imaging of maize lines widely used in field trials

PubMed Central

Liang, Zhikai; Pandey, Piyush; Stoerger, Vincent; Xu, Yuhang; Qiu, Yumou; Ge, Yufeng

2018-01-01

Abstract Background Maize (Zea mays ssp. mays) is 1 of 3 crops, along with rice and wheat, responsible for more than one-half of all calories consumed around the world. Increasing the yield and stress tolerance of these crops is essential to meet the growing need for food. The cost and speed of plant phenotyping are currently the largest constraints on plant breeding efforts. Datasets linking new types of high-throughput phenotyping data collected from plants to the performance of the same genotypes under agronomic conditions across a wide range of environments are essential for developing new statistical approaches and computer vision–based tools. Findings A set of maize inbreds—primarily recently off patent lines—were phenotyped using a high-throughput platform at University of Nebraska-Lincoln. These lines have been previously subjected to high-density genotyping and scored for a core set of 13 phenotypes in field trials across 13 North American states in 2 years by the Genomes 2 Fields Consortium. A total of 485 GB of image data including RGB, hyperspectral, fluorescence, and thermal infrared photos has been released. Conclusions Correlations between image-based measurements and manual measurements demonstrated the feasibility of quantifying variation in plant architecture using image data. However, naive approaches to measuring traits such as biomass can introduce nonrandom measurement errors confounded with genotype variation. Analysis of hyperspectral image data demonstrated unique signatures from stem tissue. Integrating heritable phenotypes from high-throughput phenotyping data with field data from different environments can reveal previously unknown factors that influence yield plasticity. PMID:29186425

Conventional and hyperspectral time-series imaging of maize lines widely used in field trials.

PubMed

Liang, Zhikai; Pandey, Piyush; Stoerger, Vincent; Xu, Yuhang; Qiu, Yumou; Ge, Yufeng; Schnable, James C

2018-02-01

Maize (Zea mays ssp. mays) is 1 of 3 crops, along with rice and wheat, responsible for more than one-half of all calories consumed around the world. Increasing the yield and stress tolerance of these crops is essential to meet the growing need for food. The cost and speed of plant phenotyping are currently the largest constraints on plant breeding efforts. Datasets linking new types of high-throughput phenotyping data collected from plants to the performance of the same genotypes under agronomic conditions across a wide range of environments are essential for developing new statistical approaches and computer vision-based tools. A set of maize inbreds-primarily recently off patent lines-were phenotyped using a high-throughput platform at University of Nebraska-Lincoln. These lines have been previously subjected to high-density genotyping and scored for a core set of 13 phenotypes in field trials across 13 North American states in 2 years by the Genomes 2 Fields Consortium. A total of 485 GB of image data including RGB, hyperspectral, fluorescence, and thermal infrared photos has been released. Correlations between image-based measurements and manual measurements demonstrated the feasibility of quantifying variation in plant architecture using image data. However, naive approaches to measuring traits such as biomass can introduce nonrandom measurement errors confounded with genotype variation. Analysis of hyperspectral image data demonstrated unique signatures from stem tissue. Integrating heritable phenotypes from high-throughput phenotyping data with field data from different environments can reveal previously unknown factors that influence yield plasticity. © The Authors 2017. Published by Oxford University Press.

Genotypic and phenotypic predictors of inflammation in patients with chronic kidney disease.

PubMed

Luttropp, Karin; Debowska, Malgorzata; Lukaszuk, Tomasz; Bobrowski, Leon; Carrero, Juan Jesus; Qureshi, Abdul Rashid; Stenvinkel, Peter; Lindholm, Bengt; Waniewski, Jacek; Nordfors, Louise

2016-12-01

In complex diseases such as chronic kidney disease (CKD), the risk of clinical complications is determined by interactions between phenotypic and genotypic factors. However, clinical epidemiological studies rarely attempt to analyse the combined effect of large numbers of phenotype and genotype features. We have recently shown that the relaxed linear separability (RLS) model of feature selection can address such complex issues. Here, it is applied to identify risk factors for inflammation in CKD. The RLS model was applied in 225 CKD stage 5 patients sampled in conjunction with dialysis initiation. Fifty-seven anthropometric or biochemical measurements and 79 genetic polymorphisms were entered into the model. The model was asked to identify phenotypes and genotypes that, when combined, could separate inflamed from non-inflamed patients. Inflammation was defined as a high-sensitivity C-reactive protein concentration above the median (5 mg/L). Among the 60 genotypic and phenotypic features predicting inflammation, 31 were genetic. Among the 10 strongest predictors of inflammation, 8 were single nucleotide polymorphisms located in the NAMPT, CIITA, BMP2 and PIK3CB genes, whereas fibrinogen and bone mineral density were the only phenotypic biomarkers. These results indicate a larger involvement of hereditary factors in inflammation than might have been expected and suggest that inclusion of genotype features in risk assessment studies is critical. The RLS model demonstrates that inflammation in CKD is determined by an extensive panel of factors and may prove to be a suitable tool that could enable a much-needed multifactorial approach as opposed to the commonly utilized single-factor analysis. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Accuracy of different bioinformatics methods in detecting antibiotic resistance and virulence factors from Staphylococcus aureus whole genome sequences.

PubMed

Mason, Amy; Foster, Dona; Bradley, Phelim; Golubchik, Tanya; Doumith, Michel; Gordon, N Claire; Pichon, Bruno; Iqbal, Zamin; Staves, Peter; Crook, Derrick; Walker, A Sarah; Kearns, Angela; Peto, Tim

2018-06-20

Background : In principle, whole genome sequencing (WGS) can predict phenotypic resistance directly from genotype, replacing laboratory-based tests. However, the contribution of different bioinformatics methods to genotype-phenotype discrepancies has not been systematically explored to date. Methods : We compared three WGS-based bioinformatics methods (Genefinder (read-based), Mykrobe (de Bruijn graph-based) and Typewriter (BLAST-based)) for predicting presence/absence of 83 different resistance determinants and virulence genes, and overall antimicrobial susceptibility, in 1379 Staphylococcus aureus isolates previously characterised by standard laboratory methods (disc diffusion, broth and/or agar dilution and PCR). Results : 99.5% (113830/114457) of individual resistance-determinant/virulence gene predictions were identical between all three methods, with only 627 (0.5%) discordant predictions, demonstrating high overall agreement (Fliess-Kappa=0.98, p<0.0001). Discrepancies when identified were in only one of the three methods for all genes except the cassette recombinase, ccrC(b ). Genotypic antimicrobial susceptibility prediction matched laboratory phenotype in 98.3% (14224/14464) cases (2720 (18.8%) resistant, 11504 (79.5%) susceptible). There was greater disagreement between the laboratory phenotypes and the combined genotypic predictions (97 (0.7%) phenotypically-susceptible but all bioinformatic methods reported resistance; 89 (0.6%) phenotypically-resistant, but all bioinformatics methods reported susceptible) than within the three bioinformatics methods (54 (0.4%) cases, 16 phenotypically-resistant, 38 phenotypically-susceptible). However, in 36/54 (67%), the consensus genotype matched the laboratory phenotype. Conclusions : In this study, the choice between these three specific bioinformatic methods to identify resistance-determinants or other genes in S. aureus did not prove critical, with all demonstrating high concordance with each other and phenotypic/molecular methods. However, each has some limitations and therefore consensus methods provide some assurance. Copyright © 2018 American Society for Microbiology.

Molecular characterization of the Fy(a-b-) phenotype in a Polish family.

PubMed

Karolak, Ewa; Grodecka, Magdalena; Suchanowska, Anna; Klausa, Elżbieta; Bochenek, Stanisława; Majorczyk, Edyta; Czerwiński, Marcin; Waśniowska, Kazimiera

2013-10-01

The Fy(a-b-) phenotype, very rare in Caucasians and defined by the homozygous FY(*)B-33 allele, is associated with the -33T>C mutation in the promoter region of the FY gene. The allele FY(*)X is correlated with weak expression of Fy(b) antigen due to 265C>T and 298G>A mutations in FY(*)B allele. The purpose of this study was molecular characterization of Fy blood group antigens in Fy(a-b-) members of a Polish family. High-resolution melting analysis was performed to detect single nucleotide polymorphisms in amplified fragments of the FY gene. The Fy(a-b-) phenotype in three siblings of the Polish family was caused by the FY(*)X/FY(*)B-33 genotype. Copyright © 2013 Elsevier Ltd. All rights reserved.

Stroke Genetics Network (SiGN) Study: Design and rationale for a genome-wide association study of ischemic stroke subtypes

PubMed Central

Meschia, James F.; Arnett, Donna K.; Ay, Hakan; Brown, Robert D.; Benavente, Oscar; Cole, John W.; de Bakker, Paul I.W.; Dichgans, Martin; Doheny, Kimberly F.; Fornage, Myriam; Grewal, Raji; Gwinn, Katrina; Jern, Christina; Conde, Jordi Jimenez; Johnson, Julie A.; Jood, Katarina; Laurie, Cathy C.; Lee, Jin-Moo; Lindgren, Arne; Markus, Hugh S.; McArdle, Patrick F.; McClure, Leslie A.; Mitchell, Braxton D.; Schmidt, Reinhold; Rexrode, Kathryn M.; Rich, Stephen S.; Rosand, Jonathan; Rothwell, Peter M.; Rundek, Tatjana; Sacco, Ralph L.; Sharma, Pankaj; Shuldiner, Alan R.; Slowik, Agnieszka; Wassertheil-Smoller, Sylvia; Sudlow, Cathie; Thijs, Vincent; Woo, Daniel; Worrall, Bradford B.; Wu, Ona; Kittner, Steven J.

2014-01-01

Background and Purpose Meta-analyses of extant genome-wide data illustrate the need to focus on subtypes of ischemic stroke for gene discovery. The NINDS Stroke Genetics Network (SiGN) contributes substantially to meta-analyses that focus on specific subtypes of stroke. Methods The NINDS Stroke Genetics Network (SiGN) includes ischemic stroke cases from 24 Genetic Research Centers (GRCs), 13 from the US and 11 from Europe. Investigators harmonize ischemic stroke phenotyping using the web-based Causative Classification of Stroke (CCS) system, with data entered by trained and certified adjudicators at participating GRCs. Through the Center for Inherited Diseases Research (CIDR), SiGN plans to genotype 10,296 carefully phenotyped stroke cases using genome-wide SNP arrays, and add to these another 4,253 previously genotyped cases for a total of 14,549 cases. To maximize power for subtype analyses, the study allocates genotyping resources almost exclusively to cases. Publicly available studies provide most of the control genotypes. CIDR-generated genotypes and corresponding phenotypic data will be shared with the scientific community through dbGaP, and brain MRI studies will be centrally archived. Conclusions The SiGN consortium, with its emphasis on careful and standardized phenotyping of ischemic stroke and stroke subtypes, provides an unprecedented opportunity to uncover genetic determinants of ischemic stroke. PMID:24021684

Utilization of a high-throughput shoot imaging system to examine the dynamic phenotypic responses of a C4 cereal crop plant to nitrogen and water deficiency over time

PubMed Central

Neilson, E. H.; Edwards, A. M.; Blomstedt, C. K.; Berger, B.; Møller, B. Lindberg; Gleadow, R. M.

2015-01-01

The use of high-throughput phenotyping systems and non-destructive imaging is widely regarded as a key technology allowing scientists and breeders to develop crops with the ability to perform well under diverse environmental conditions. However, many of these phenotyping studies have been optimized using the model plant Arabidopsis thaliana. In this study, The Plant Accelerator® at The University of Adelaide, Australia, was used to investigate the growth and phenotypic response of the important cereal crop, Sorghum bicolor L. Moench and related hybrids to water-limited conditions and different levels of fertilizer. Imaging in different spectral ranges was used to monitor plant composition, chlorophyll, and moisture content. Phenotypic image analysis accurately measured plant biomass. The data set obtained enabled the responses of the different sorghum varieties to the experimental treatments to be differentiated and modelled. Plant architectural instead of architecture elements were determined using imaging and found to correlate with an improved tolerance to stress, for example diurnal leaf curling and leaf area index. Analysis of colour images revealed that leaf ‘greenness’ correlated with foliar nitrogen and chlorophyll, while near infrared reflectance (NIR) analysis was a good predictor of water content and leaf thickness, and correlated with plant moisture content. It is shown that imaging sorghum using a high-throughput system can accurately identify and differentiate between growth and specific phenotypic traits. R scripts for robust, parsimonious models are provided to allow other users of phenomic imaging systems to extract useful data readily, and thus relieve a bottleneck in phenotypic screening of multiple genotypes of key crop plants. PMID:25697789

X-linked recessive nephrogenic diabetes insipidus: a clinico-genetic study.

PubMed

Hong, Che Ry; Kang, Hee Gyung; Choi, Hyun Jin; Cho, Min Hyun; Lee, Jung Won; Kang, Ju Hyung; Park, Hye Won; Koo, Ja Wook; Ha, Tae-Sun; Kim, Su-Yung; Il Cheong, Hae

2014-01-01

A retrospective genotype and phenotype analysis of X-linked congenital nephrogenic diabetes insipidus (NDI) was conducted on a nationwide cohort of 25 (24 male, 1 female) Korean children with AVPR2 gene mutations, comparing non-truncating and truncating mutations. In an analysis of male patients, the median age at diagnosis was 0.9 years old. At a median follow-up of 5.4 years, urinary tract dilatations were evident in 62% of patients and their median glomerular filtration rate was 72 mL/min/1.73 m2. Weights and heights were under the 3rd percentile in 22% and 33% of patients, respectively. One patient had low intelligence quotient and another developed end-stage renal disease. No statistically significant genotype-phenotype correlation was found between non-truncating and truncating mutations. One patient was female; she was analyzed separately because inactivation and mosaicism of the X chromosome may influence clinical manifestations in female patients. Current unsatisfactory long-term outcome of congenital NDI necessitates a novel therapeutic strategy.

Physical Model of the Genotype-to-Phenotype Map of Proteins

NASA Astrophysics Data System (ADS)

Tlusty, Tsvi; Libchaber, Albert; Eckmann, Jean-Pierre

2017-04-01

How DNA is mapped to functional proteins is a basic question of living matter. We introduce and study a physical model of protein evolution which suggests a mechanical basis for this map. Many proteins rely on large-scale motion to function. We therefore treat protein as learning amorphous matter that evolves towards such a mechanical function: Genes are binary sequences that encode the connectivity of the amino acid network that makes a protein. The gene is evolved until the network forms a shear band across the protein, which allows for long-range, soft modes required for protein function. The evolution reduces the high-dimensional sequence space to a low-dimensional space of mechanical modes, in accord with the observed dimensional reduction between genotype and phenotype of proteins. Spectral analysis of the space of 1 06 solutions shows a strong correspondence between localization around the shear band of both mechanical modes and the sequence structure. Specifically, our model shows how mutations are correlated among amino acids whose interactions determine the functional mode.

Mapping the functional landscape of frequent phenylalanine hydroxylase (PAH) genotypes promotes personalised medicine in phenylketonuria.

PubMed

Danecka, Marta K; Woidy, Mathias; Zschocke, Johannes; Feillet, François; Muntau, Ania C; Gersting, Søren W

2015-03-01

In phenylketonuria, genetic heterogeneity, frequent compound heterozygosity, and the lack of functional data for phenylalanine hydroxylase genotypes hamper reliable phenotype prediction and individualised treatment. A literature search revealed 690 different phenylalanine hydroxylase genotypes in 3066 phenylketonuria patients from Europe and the Middle East. We determined phenylalanine hydroxylase function of 30 frequent homozygous and compound heterozygous genotypes covering 55% of the study population, generated activity landscapes, and assessed the phenylalanine hydroxylase working range in the metabolic (phenylalanine) and therapeutic (tetrahydrobiopterin) space. Shared patterns in genotype-specific functional landscapes were linked to biochemical and pharmacological phenotypes, where (1) residual activity below 3.5% was associated with classical phenylketonuria unresponsive to pharmacological treatment; (2) lack of defined peak activity induced loss of response to tetrahydrobiopterin; (3) a higher cofactor need was linked to inconsistent clinical phenotypes and low rates of tetrahydrobiopterin response; and (4) residual activity above 5%, a defined peak of activity, and a normal cofactor need were associated with pharmacologically treatable mild phenotypes. In addition, we provide a web application for retrieving country-specific information on genotypes and genotype-specific phenylalanine hydroxylase function that warrants continuous extension, updates, and research on demand. The combination of genotype-specific functional analyses with biochemical, clinical, and therapeutic data of individual patients may serve as a powerful tool to enable phenotype prediction and to establish personalised medicine strategies for dietary regimens and pharmacological treatment in phenylketonuria. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Data from a large European study indicate that the outcome of primary hyperoxaluria type 1 correlates with the AGXT mutation type.

PubMed

Mandrile, Giorgia; van Woerden, Christiaan S; Berchialla, Paola; Beck, Bodo B; Acquaviva Bourdain, Cécile; Hulton, Sally-Anne; Rumsby, Gill

2014-12-01

Primary hyperoxaluria type 1 displays a heterogeneous phenotype, likely to be affected by genetic and non-genetic factors, including timeliness of diagnosis and quality of care. As previous genotype-phenotype studies were hampered by limited patient numbers the European OxalEurope Consortium was constituted. This preliminary retrospective report is based on 526 patients of which 410 have the AGXT genotype defined. We grouped mutations by the predicted effect as null, missense leading to mistargeting (G170R), and other missense, and analyzed their phenotypic correlations. Median age of end-stage renal disease increased from 9.9 for 88 homozygous null patients, 11.5 for 42 heterozygous null/missense, 16.9 for 116 homozygous missense patients, 25.1 for 61 G170R/null patients, 31.2 for 32 G170R/missense patients, and 33.9 years for 71 homozygous G170R patients. The outcome of some recurrent missense mutations (p.I244T, p.F152I, p.M195R, p.D201E, p.S81L, p.R36C) and an unprecedented number of G170R homozygotes is described in detail. Diagnosis is still delayed and actions aimed at increasing awareness of primary hyperoxaluria type 1 are recommended. Thus, in addition to G170R, other causative mutations are associated with later onset of end-stage renal disease. The OxalEurope registry will provide necessary tools for characterizing those genetic and non-genetic factors through a combination of genetic, functional, and biostatistical approaches.

Lactase persistence versus lactose intolerance: Is there an intermediate phenotype?

PubMed

Dzialanski, Zbigniew; Barany, Michael; Engfeldt, Peter; Magnuson, Anders; Olsson, Lovisa A; Nilsson, Torbjörn K

2016-02-01

According to the prevailing theory about the genetic background to lactose intolerance, there are three genotypes but only two adult physiological phenotypes: lactase persistence in individuals with the CT and TT genotypes and lactase non-persistence in individuals with the CC genotype. However, analysis of lactase activity from intestinal biopsies has revealed three distinct levels of activity, suggesting that an intermediate physiological phenotype may exist. To assess possible disparities between different genotypes with regard to biomarkers of lactase activity and physical symptoms during an oral lactose load test. A retrospective study using an oral lactose load test (n=487). Concentrations of hydrogen in exhaled air and blood glucose were measured. Afterwards, subjects were asked to provide oral mucosa samples for genotyping and answer a questionnaire (participation rate 56%, n=274). Mean hydrogen levels in exhaled air at 120min were significantly higher in the CT genotype than in the TT genotype. There was no significant difference in blood glucose levels between the two groups. Reported symptoms, with the possible exception of abdominal pain, were equally prevalent in both groups. Subjects with the CT and TT genotypes, hitherto classified as lactase-persistent, differ in their physiological response to lactose intake, indicating differences in phenotype which could have clinical significance. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Weak D caused by a founder deletion in the RHD gene.

PubMed

Fichou, Yann; Chen, Jian-Min; Le Maréchal, Cédric; Jamet, Déborah; Dupont, Isabelle; Chuteau, Claude; Durousseau, Cécile; Loirat, Marie-Jeanne; Bailly, Pascal; Férec, Claude

2012-11-01

The RhD blood group system exemplifies a genotype-phenotype correlation by virtue of its highly polymorphic and immunogenic nature. Weak D phenotypes are generally thought to result from missense mutations leading to quantitative change of the D antigen in the red blood cell membrane or intracellularly. Different sets of polymerase chain reaction primers were designed to map and clone a deletion involving RHD Exon 10, which was found in approximately 3% of approximately 2000 RHD hemizygous subjects with D phenotype ambiguity. D antigen density was measured by flow cytometry. Transcript analysis was carried out by 3'-rapid amplification of complementary DNA ends. Haplotype analysis was performed by microsatellite genotyping. A 5405-bp deletion that removed nearly two-thirds of Intron 9 and almost all of Exon 10 of the RHD gene was characterized. It is predicted to result in the replacement of the last eight amino acids of the wild-type RhD protein by another four amino acids. The mean RhD antigen density from two deletion carriers was determined to be only 30. A consensus haplotype could be deduced from the deletion carriers based on the microsatellite genotyping data. The currently reported deletion was derived from a common founder. This deletion appears to represent not only the first large deletion associated with weak D but also the weakest of weak D alleles so far reported. This highly unusual genotype-phenotype relationship may be attributable to the additive effect of three distinct mechanisms that affect mRNA formation, mRNA stability, and RhD/ankyrin-R interaction, respectively. © 2012 American Association of Blood Banks.

Novel types of COMP mutations and genotype-phenotype association in pseudoachondroplasia and multiple epiphyseal dysplasia.

PubMed

Mabuchi, Akihiko; Manabe, Noriyo; Haga, Nobuhiko; Kitoh, Hiroshi; Ikeda, Toshiyuki; Kawaji, Hiroyuki; Tamai, Kazuya; Hamada, Junichiro; Nakamura, Shigeru; Brunetti-Pierri, Nicola; Kimizuka, Mamori; Takatori, Yoshio; Nakamura, Kozo; Nishimura, Gen; Ohashi, Hirofumi; Ikegawa, Shiro

2003-01-01

Mutations in the gene encoding cartilage oligomeric matrix protein ( COMP) cause two skeletal dysplasias, pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED). More than 40 mutations have been identified; however, genotype-phenotype relationships are not well delineated. Further, mutations other than in-frame insertion/deletions and substitutions have not been found, and currently known mutations are clustered within relatively small regions. Here we report the identification of nine novel and three recurrent COMP mutations in PSACH and MED patients. These include two novel types of mutations; the first, a gross deletion spanning an exon-intron junction, causes an exon deletion. The second, a frameshift mutation that results in a truncation of the C-terminal domain, is the first known truncating mutation in the COMP gene. The remaining mutations, other than a novel exon 18 mutation, affected highly conserved aspartate or cysteine residues in the calmodulin-like repeat (CLR) region. Genotype-phenotype analysis revealed a correlation between the position and type of mutations and the severity of short stature. Mutations in the seventh CLR produced more severe short stature compared with mutations elsewhere in the CLRs ( P=0.0003) and elsewhere in the COMP gene ( P=0.0007). Patients carrying mutations within the five-aspartates repeat (aa 469-473) in the seventh CLR were extremely short (below -6 SD). Patients with deletion mutations were significantly shorter than those with substitution mutations ( P=0.0024). These findings expand the mutation spectrum of the COMP gene and highlight genotype-phenotype relationships, facilitating improved genetic diagnosis and analysis of COMP function in humans.

Informative markers identification and multivariate analysis of selected DxP for the purpose of QTL mapping

NASA Astrophysics Data System (ADS)

Hazirah S., Z.; Maizura, I.; Rajinder, S.; Mohd Isa Z., A.; Ismanizan, I.

2014-09-01

A study was carried out to generate a linkage map of oil palm dura x pisifera (DXP) population. A subset of sample from a DXP mapping family was screened using 325 SSR primers, of which 221 were informative. To date, 150 SSRs have been genotyped across the entire DxP population via capillary sequencer, where 73 SSRs had 1:1 segregation ratio, 64 had 1:1:1:1, 3 had 3:1 and ten had 1:2:1 segregation ratios. Kolmogorov-Smirnov tests by SPSS revealed that most of the bunch quality components had normal distribution which fulfilled one of the pre-requisites to carry out phenotype-genotype correlation association.

Factor VII deficiency: a novel missense variant and genotype-phenotype correlation in patients from Southern Italy.

PubMed

Tiscia, Giovanni; Favuzzi, Giovanni; Chinni, Elena; Colaizzo, Donatella; Fischetti, Lucia; Intrieri, Mariano; Margaglione, Maurizio; Grandone, Elvira

2017-01-01

This study aimed at attempting to correlate genotype and phenotype in factor VII deficiency. Here, we present molecular and clinical findings of 10 patients with factor VII deficiency. From 2013 to 2016, 10 subjects were referred to our center because of a prolonged prothrombin time identified during routine or presurgery examinations or after a laboratory assessment of a bleeding episode. Mutation characterization was performed using the bioinformatics applications PROMO, SIFT, and Polyphen-2. Structural changes in the factor VII protein were analyzed using the SPDB viewer tool. Of the 10 variants we identified, 1 was responsible for a novel missense change (c.1199G>C, p.Cys400Ser); in 2 cases we identified the c.-54G>A and c.509G>A (p.Arg170His) polymorphic variants in the 5'-upstream region of the factor VII gene and exon 6, respectively. To our knowledge, neither of these polymorphic variants has been described previously in factor VII-deficient patients. In silico predictions showed differences in binding sites for transcription factors caused by the c.-54G>A variant and a probable damaging effect of the p.Cys400Ser missense change on factor VII active conformation, leading to breaking of the Cys400-Cys428 disulfide bridge. Our findings further suggest that, independently of factor VII levels and of variants potentially affecting factor VII levels, environmental factors, e.g., trauma, could heavily influence the clinical phenotype of factor VII-deficient patients.

The importance of functional tests to assess the effect of a new CFTR variant when genotype-phenotype correlation is not possible.

PubMed

Hinzpeter, Alexandre; Reboul, Marie-Pierre; Callebaut, Isabelle; Zordan, Cécile; Costes, Bruno; Guichoux, Julie; Iron, Albert; Lacombe, Didier; Martin, Natacha; Arveiler, Benoit; Fanen, Pascale; Fergelot, Patricia; Girodon, Emmanuelle

2017-05-01

In vitro functional tests aimed to investigate CFTR dysfunction appear critical to help elucidate the functional impact of new variants of uncertain clinical significance and solve inconclusive cases, especially in early deceased newborns.

Structural variation within the potato Ve gene locus and correlation with molecular marker analysis

USDA-ARS?s Scientific Manuscript database

The disconnect between single genotype model systems and plant breeding using wide crosses of diverse germplasm is often too great to affect progress in understanding complex phenotypes. Whole genome sequencing allows researchers and breeders to quickly and inexpensively resequence interesting indiv...

Interclonal proteomic responses to predator exposure in Daphnia magna may depend on predator composition of habitats.

PubMed

Otte, Kathrin A; Schrank, Isabella; Fröhlich, Thomas; Arnold, Georg J; Laforsch, Christian

2015-08-01

Phenotypic plasticity, the ability of one genotype to express different phenotypes in response to changing environmental conditions, is one of the most common phenomena characterizing the living world and is not only relevant for the ecology but also for the evolution of species. Daphnia, the water flea, is a textbook example for predator-induced phenotypic plastic defences; however, the analysis of molecular mechanisms underlying these inducible defences is still in its early stages. We exposed Daphnia magna to chemical cues of the predator Triops cancriformis to identify key processes underlying plastic defensive trait formation. To get a more comprehensive idea of this phenomenon, we studied four genotypes with five biological replicates each, originating from habitats characterized by different predator composition, ranging from predator-free habitats to habitats containing T. cancriformis. We analysed the morphologies as well as proteomes of predator-exposed and control animals. Three genotypes showed morphological changes when the predator was present. Using a high-throughput proteomics approach, we found 294 proteins which were significantly altered in their abundance after predator exposure in a general or genotype-dependent manner. Proteins connected to genotype-dependent responses were related to the cuticle, protein synthesis and calcium binding, whereas the yolk protein vitellogenin increased in abundance in all genotypes, indicating their involvement in a more general response. Furthermore, genotype-dependent responses at the proteome level were most distinct for the only genotype that shares its habitat with Triops. Altogether, our study provides new insights concerning genotype-dependent and general molecular processes involved in predator-induced phenotypic plasticity in D. magna. © 2015 John Wiley & Sons Ltd.

A rare CYP21A2 mutation in a congenital adrenal hyperplasia kindred displaying genotype-phenotype nonconcordance.

PubMed

Khattab, Ahmed; Yuen, Tony; Al-Malki, Sultan; Yau, Mabel; Kazmi, Diya; Sun, Li; Harbison, Madeleine; Haider, Shozeb; Zaidi, Mone; New, Maria I

2016-01-01

Congenital adrenal hyperplasia (CAH) owing to 21-hydroxylase deficiency is caused by the autosomal recessive inheritance of mutations in the gene CYP21A2. CYP21A2 mutations lead to variable impairment of the 21-hydroxylase enzyme, which, in turn, is associated with three clinical phenotypes, namely, salt wasting, simple virilizing, and nonclassical CAH. However, it is known that a given mutation can associate with different clinical phenotypes, resulting in a high rate of genotype-phenotype nonconcordance. We aimed to study the genotype-phenotype nonconcordance in a family with three siblings affected with nonclassical CAH. All had hormonal evidence of nonclassical CAH, but this phenotype could not be explained by the genotype obtained from commercial CYP21A2 genetic testing, which revealed heterozygosity for the maternal 30 kb deletion mutation. We performed Sanger sequencing of the entire CYP21A2 gene in this family to search for a rare mutation that was not covered by commercial testing and found in the three siblings a second, rare c.1097G>A (p.R366H) mutation in exon 8. Computational modeling confirmed that this was a mild mutation consistent with nonclassical CAH. We recommend that sequencing of entire genes for rare mutations should be carried out when genotype-phenotype nonconcordance is observed in patients with autosomal recessive monogenic disorders, including CAH. © 2015 New York Academy of Sciences.

Utility of Phenotypic and Genotypic Testing in the Study of Mycobacterium tuberculosis Resistance to First-Line Anti-Tuberculosis drugs.

PubMed

Alba Álvarez, Luz María; García García, José María; Pérez Hernández, M Dolores; Martínez González, Susana; Palacios Gutiérrez, Juan José

2017-04-01

To determine the utility of molecular techniques in the diagnosis of resistance and the extent of resistance to first-line drugs in our region. From 2004 to 2013, 1,889 strains of Mycobacterium tuberculosis complex isolated in Asturias, Spain, were studied using phenotypic (Clinical and Laboratory Standards Institute guidelines) and molecular (INNOLiPA RIF-TB © ; GenotypeMDRplus © ; GenotypeMDRsl © ) sensitivity tests. 1,759 strains (94.52%) were sensitive to all first-line drugs, and 102 strains (5.48%) showed some resistance: 81 strains (4.35%) were resistant to 1 single drug, 14 (0.75%) were polyresistant, and 7 (0.37%) were multiresistant (resistant to rifampicin and isoniazid). In total, 137 resistances were identified: 60 to isoniazid (3.22%), 7 to rifampicin (0.37%), 9 to pyrazinamide (0.48%), 11 to ethambutol (0.59%), and 50 to streptomycin (2.68%). Of the mutations detected, 75.9% (63/83) correlated with resistance, while 24.09% of mutations detected (20/83) were not associated with resistance; 16 of these involved a silent mutation at codon 514 of the rpoB gene. Between 0 and 90% of strains, depending on the drug under consideration, were resistant even when no gene mutations were detected using marketed systems. Molecular techniques are very useful, particularly for obtaining rapid results, but these must be confirmed with standard phenotypic sensitivity testing. The rate of resistance in our region is low and multi-drug resistantcases (0.37%) are sporadic. Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

Recognition of the polycistronic nature of human genes is critical to understanding the genotype-phenotype relationship.

PubMed

Brunet, Marie A; Levesque, Sébastien A; Hunting, Darel J; Cohen, Alan A; Roucou, Xavier

2018-05-01

Technological advances promise unprecedented opportunities for whole exome sequencing and proteomic analyses of populations. Currently, data from genome and exome sequencing or proteomic studies are searched against reference genome annotations. This provides the foundation for research and clinical screening for genetic causes of pathologies. However, current genome annotations substantially underestimate the proteomic information encoded within a gene. Numerous studies have now demonstrated the expression and function of alternative (mainly small, sometimes overlapping) ORFs within mature gene transcripts. This has important consequences for the correlation of phenotypes and genotypes. Most alternative ORFs are not yet annotated because of a lack of evidence, and this absence from databases precludes their detection by standard proteomic methods, such as mass spectrometry. Here, we demonstrate how current approaches tend to overlook alternative ORFs, hindering the discovery of new genetic drivers and fundamental research. We discuss available tools and techniques to improve identification of proteins from alternative ORFs and finally suggest a novel annotation system to permit a more complete representation of the transcriptomic and proteomic information contained within a gene. Given the crucial challenge of distinguishing functional ORFs from random ones, the suggested pipeline emphasizes both experimental data and conservation signatures. The addition of alternative ORFs in databases will render identification less serendipitous and advance the pace of research and genomic knowledge. This review highlights the urgent medical and research need to incorporate alternative ORFs in current genome annotations and thus permit their inclusion in hypotheses and models, which relate phenotypes and genotypes. © 2018 Brunet et al.; Published by Cold Spring Harbor Laboratory Press.

The effects of stabilizing and directional selection on phenotypic and genotypic variation in a population of RNA enzymes.

PubMed

Hayden, Eric J; Bratulic, Sinisa; Koenig, Iwo; Ferrada, Evandro; Wagner, Andreas

2014-02-01

The distribution of variation in a quantitative trait and its underlying distribution of genotypic diversity can both be shaped by stabilizing and directional selection. Understanding either distribution is important, because it determines a population's response to natural selection. Unfortunately, existing theory makes conflicting predictions about how selection shapes these distributions, and very little pertinent experimental evidence exists. Here we study a simple genetic system, an evolving RNA enzyme (ribozyme) in which a combination of high throughput genotyping and measurement of a biochemical phenotype allow us to address this question. We show that directional selection, compared to stabilizing selection, increases the genotypic diversity of an evolving ribozyme population. In contrast, it leaves the variance in the phenotypic trait unchanged.

Connectome-Wide Phenotypical and Genotypical Associations in Focal Dystonia

PubMed Central

Fuertinger, Stefan

2017-01-01

Isolated focal dystonia is a debilitating movement disorder of unknown pathophysiology. Early studies in focal dystonias have pointed to segregated changes in brain activity and connectivity. Only recently has the notion that dystonia pathophysiology may lie in abnormalities of large-scale brain networks appeared in the literature. Here, we outline a novel concept of functional connectome-wide alterations that are linked to dystonia phenotype and genotype. Using a neural community detection strategy and graph theoretical analysis of functional MRI data in human patients with the laryngeal form of dystonia (LD) and healthy controls (both males and females), we identified an abnormally widespread hub formation in LD, which particularly affected the primary sensorimotor and parietal cortices and thalamus. Left thalamic regions formed a delineated functional community that highlighted differences in network topology between LD patients with and without family history of dystonia. Conversely, marked differences in the topological organization of parietal regions were found between phenotypically different forms of LD. The interface between sporadic genotype and adductor phenotype of LD yielded four functional communities that were primarily governed by intramodular hub regions. Conversely, the interface between familial genotype and abductor phenotype was associated with numerous long-range hub nodes and an abnormal integration of left thalamus and basal ganglia. Our findings provide the first comprehensive atlas of functional topology across different phenotypes and genotypes of focal dystonia. As such, this study constitutes an important step toward defining dystonia as a large-scale network disorder, understanding its causative pathophysiology, and identifying disorder-specific markers. SIGNIFICANCE STATEMENT The architecture of the functional connectome in focal dystonia was analyzed in a large population of patients with laryngeal dystonia. Breaking with the empirical concept of dystonia as a basal ganglia disorder, we discovered large-scale alterations of neural communities that are significantly influenced by the disorder's clinical phenotype and genotype. PMID:28674168

Biotinidase deficiency: Genotype-biochemical phenotype association in Brazilian patients

PubMed Central

Borsatto, Taciane; Sperb-Ludwig, Fernanda; Lima, Samyra E.; S. Carvalho, Maria R.; S. Fonseca, Pablo A.; S. Camelo, José; M. Ribeiro, Erlane; F. V. de Medeiros, Paula; M. Lourenço, Charles; F. M. de Souza, Carolina; Boy, Raquel; Félix, Têmis M.; M. Bittar, Camila; L. C. Pinto, Louise; C. Neto, Eurico; J. Blom, Henk; D. Schwartz, Ida V.

2017-01-01

Introduction The association between the BTD genotype and biochemical phenotype [profound biotinidase deficiency (BD), partial BD or heterozygous activity] is not always consistent. This study aimed to investigate the genotype-biochemical phenotype association in patients with low biotinidase activity. Methods All exons, the 5'UTR and the promoter of the BTD gene were sequenced in 72 Brazilian individuals who exhibited low biotinidase activity. For each patient, the expected biochemical phenotype based on the known genotype was compared with the observed biochemical phenotype. Additional non-genetic factors that could affect the biotinidase activity were also analysed. Results Most individuals were identified by neonatal screening (n = 66/72). When consecutive results for the same patient were compared, age, prematurity and neonatal jaundice appeared to affect the level of biotinidase activity. The biochemical phenotype at the time of the second blood collection changed in 11/22 patients compared to results from the first sample. Three novel variants were found: c.1337T>C (p.L446P), c.1466A>G (p.N489S) and c.962G>A (p.W321*). Some patients with the same genotype presented different biochemical phenotypes. The expected and observed biochemical phenotypes agreed in 68.5% of cases (concordant patients). The non-coding variants c.-183G>A, c.-315A>G and c.-514C>T were present in heterozygosis in 5/17 discordant patients. In addition, c.-183G>A and c.-514C>T were also present in 10/37 concordant patients. Conclusions The variants found in the promoter region do not appear to have a strong impact on biotinidase activity. Since there is a disparity between the BTD genotype and biochemical phenotype, and biotinidase activity may be affected by both genetic and non-genetic factors, we suggest that the diagnosis of BD should be based on more than one measurement of plasma biotinidase activity. DNA analysis can be of additional relevance to differentiate between partial BD and heterozygosity. PMID:28498829

Swedish CDKN2A mutation carriers do not present the atypical mole syndrome phenotype.

PubMed

Nielsen, Kari; Harbst, Katja; Måsbäck, Anna; Jönsson, Göran; Borg, Ake; Olsson, Håkan; Ingvar, Christian

2010-08-01

Phenotypic characteristics were examined in melanoma-prone southern Swedish CDKN2A (p16-113insArg/p14ARF-128insSer) mutation families, in relation to the CDKN2A genotype, nevi, clinically atypical nevi (CAN) and melanoma. Individuals from eight melanoma-prone families, with index patients carrying the CDKN2A mutation, were offered skin examinations and genotyping (CDKN2A and MC1R). Ninety-three individuals above 18 years of age participated; 29 invasive melanomas in 16 patients were recorded, all in the 38 verified CDKN2A mutation carriers. Median age at diagnosis was 36 years. Several MC1R variants were observed. A significant correlation to CAN (P=0.01) and red hair colour (P=0.02) could be confirmed in melanoma patients. A positive mutation status (CDKN2A) was correlated to one or more CAN (P=0.007) but neither to blue eyes, red hair colour, heavy freckling nor high number of nevi. For mutation carriers, median total naevus count was 24 and interquartile range was 12-47 (mean 31); whereas for the whole cohort, median total naevus count was 12 and interquartile range was 5-25 (mean 22). No participant fulfilled the atypical mole syndrome phenotype criteria. Melanomas were diagnosed only in mutation carriers, and melanoma diagnosis was statistically correlated to the presence of one or more CAN and red hair colour, supporting the possible synergistic effect of a MC1R mutation on increased risk of melanoma in patients with a CDKN2A mutation. Family history, with verified tumour diagnoses, remains an important clinical tool for finding mutation carriers for referral to clinical geneticists and simultaneous presence of CAN in probable mutation carriers might strengthen this indication. The atypical mole syndrome phenotype was, however, not verified in the studied families and total naevus counts were low.

Phenotype Heterogeneity in Glucokinase-Maturity-Onset Diabetes of the Young (GCK-MODY) Patients.

PubMed

Wędrychowicz, Anna; Tobór, Ewa; Wilk, Magdalena; Ziółkowska-Ledwith, Ewa; Rams, Anna; Wzorek, Katarzyna; Sabal, Barbara; Stelmach, Małgorzata; Starzyk, Jerzy B

2017-09-01

The aim of the study was to evaluate the clinical phenotypes of glucokinase-maturity-onset diabetes of the young (GCK-MODY) pediatric patients from Southwest Poland and to search for phenotype-genotype correlations. We conducted a retrospective analysis of data on 37 CGK-MODY patients consisting of 21 girls and 16 boys of ages 1.9-20.1 (mean 12.5±5.2) years, treated in our centre in the time period between 2002 and 2013. GCK-MODY carriers were found in a frequency of 3% among 1043 diabetes mellitus (DM) patients and constituted the second most numerous group of DM patients, following type 1 DM, in our centre. The mean age of GCK-MODY diagnosis was 10.4±4.5 years. The findings leading to the diagnosis were impaired fasting glucose (IFG) (15/37), symptoms of hyperglycemia (4/37), and a GCK-MODY family history (18/37). Mean fasting blood glucose level was 6.67±1.64 mmol/L. In the sample, there were patients with normal values (4/37), those with DM (10/37), and IFG (23/37). In OGTT, 120 min glucose level was normal in 8, diabetic in 2, and characteristic for glucose intolerance in 27 of the 37 cases. Twelve of the 37 cases (32%) were identified as GCK-MODY carriers. In the total group, mean C-peptide level was 2.13±0.65 ng/mL and HbA1c was 6.26±0.45% (44.9±-18 mmol/mol). Thirty-two patients had a family history of DM. DM autoantibodies were detected in two patients. The most common mutations were p.Gly318Arg (11/37) and p.Val302Leu (8/37). There was no correlation between type of mutations and plasma glucose levels. The phenotype of GCK-MODY patients may vary from those characteristic for other DM types to an asymptomatic state with normal FG with no correlation with genotype.

Genotype-phenotype associations in WT1 glomerulopathy.

PubMed

Lipska, Beata S; Ranchin, Bruno; Iatropoulos, Paraskevas; Gellermann, Jutta; Melk, Anette; Ozaltin, Fatih; Caridi, Gianluca; Seeman, Tomas; Tory, Kalman; Jankauskiene, Augustina; Zurowska, Aleksandra; Szczepanska, Maria; Wasilewska, Anna; Harambat, Jerome; Trautmann, Agnes; Peco-Antic, Amira; Borzecka, Halina; Moczulska, Anna; Saeed, Bassam; Bogdanovic, Radovan; Kalyoncu, Mukaddes; Simkova, Eva; Erdogan, Ozlem; Vrljicak, Kristina; Teixeira, Ana; Azocar, Marta; Schaefer, Franz

2014-05-01

WT1 mutations cause a wide spectrum of renal and extrarenal manifestations. Here we evaluated disease prevalence, phenotype spectrum, and genotype-phenotype correlations of 61 patients with WT1-related steroid-resistant nephrotic syndrome relative to 700 WT1-negative patients, all with steroid-resistant nephrotic syndrome. WT1 patients more frequently presented with chronic kidney disease and hypertension at diagnosis and exhibited more rapid disease progression. Focal segmental glomerulosclerosis was equally prevalent in both cohorts, but diffuse mesangial sclerosis was largely specific for WT1 disease and was present in 34% of cases. Sex reversal and/or urogenital abnormalities (52%), Wilms tumor (38%), and gonadoblastoma (5%) were almost exclusive to WT1 disease. Missense substitutions affecting DNA-binding residues were associated with diffuse mesangial sclerosis (74%), early steroid-resistant nephrotic syndrome onset, and rapid progression to ESRD. Truncating mutations conferred the highest Wilms tumor risk (78%) but typically late-onset steroid-resistant nephrotic syndrome. Intronic (KTS) mutations were most likely to present as isolated steroid-resistant nephrotic syndrome (37%) with a median onset at an age of 4.5 years, focal segmental glomerulosclerosis on biopsy, and slow progression (median ESRD age 13.6 years). Thus, there is a wide range of expressivity, solid genotype-phenotype associations, and a high risk and significance of extrarenal complications in WT1-associated nephropathy. We suggest that all children with steroid-resistant nephrotic syndrome undergo WT1 gene screening.

Roles of Female and Male Genotype in Post-Mating Responses in Drosophila melanogaster.

PubMed

Delbare, Sofie Y N; Chow, Clement Y; Wolfner, Mariana F; Clark, Andrew G

2017-10-30

Mating induces a multitude of changes in female behavior, physiology, and gene expression. Interactions between female and male genotype lead to variation in post-mating phenotypes and reproductive success. So far, few female molecules responsible for these interactions have been identified. Here, we used Drosophila melanogaster from 5 geographically dispersed populations to investigate such female × male genotypic interactions at the female transcriptomic and phenotypic levels. Females from each line were singly-mated to males from the same 5 lines, for a total of 25 combinations. Reproductive output and refractoriness to re-mating were assayed in females from the 25 mating combinations. Female × male genotypic interactions resulted in significant differences in these post-mating phenotypes. To assess whether female × male genotypic interactions affect the female post-mating transcriptome, next-generation RNA sequencing was performed on virgin and mated females at 5 to 6 h post-mating. Seventy-seven genes showed strong variation in mating-induced expression changes in a female × male genotype-dependent manner. These genes were enriched for immune response and odorant-binding functions, and for expression exclusively in the head. Strikingly, variation in post-mating transcript levels of a gene encoding a spermathecal endopeptidase was correlated with short-term egg production. The transcriptional variation found in specific functional classes of genes might be a read-out of female × male compatibility at a molecular level. Understanding the roles these genes play in the female post-mating response will be crucial to better understand the evolution of post-mating responses and related conflicts between the sexes. © The American Genetic Association 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Evidence for biochemical and physiological differences between enzyme genotypes in Drosophila melanogaster.

PubMed Central

Cavener, D R; Clegg, M T

1981-01-01

The in vivo flux of carbon through the pentose shunt is investigated as a function of different 6-phosphogluconate dehydrogenase (6Pgd) and glucose-6-phosphate dehydrogenase (G6pd) genotypes by using differential radioactive labeling of the C-1 and C-6 positions of glucose. Alternative 6Pgd-G6pd genotypes are shown to differ in relative in vivo carbon flux through the pentose shunt. The relative in vitro specific activity differences between the 6PgdSS and 6PgdFF genotypes appear to be primarily responsible for these differences. In addition, the pentose-shunt activity is correlated with the rate of lipid synthesis. This correlation is consistent with the major metabolic function of the pathway, which is to produce NADPH for lipid synthesis. Taken together, the results of these experiments show that different genotypes of 6Pgd are associated with measurable biochemical and physiological differences. Higher order phenotypic differences of this kind must be demonstrated to support the hypothesis that natural selection can discriminate among allozymes of a given genetic locus. PMID:6794031

Epidermolysis bullosa with congenital pyloric atresia: novel mutations in the beta 4 integrin gene (ITGB4) and genotype/phenotype correlations.

PubMed

Nakano, A; Pulkkinen, L; Murrell, D; Rico, J; Lucky, A W; Garzon, M; Stevens, C A; Robertson, S; Pfendner, E; Uitto, J

2001-05-01

Epidermolysis bullosa with pyloric atresia (EB-PA: OMIM 226730), also known as Carmi syndrome, is a rare autosomal recessive genodermatosis that manifests with neonatal mucocutaneous fragility associated with congenital pyloric atresia. The disease is frequently lethal within the first year, but nonlethal cases have been reported. Mutations in the genes encoding subunit polypeptides of the alpha 6 beta 4 integrin (ITGA6 and ITGB4) have been demonstrated in EB-PA patients. To extend the repertoire of mutations and to identify genotype-phenotype correlations, we examined seven new EB-PA families, four with lethal and three with nonlethal disease variants. DNA from patients was screened for mutations using heteroduplex analysis followed by nucleotide sequencing of PCR products spanning all beta 4 integrin-coding sequences. Mutation analysis disclosed 12 distinct mutations, 11 of them novel. Four mutations predicted a premature termination codon as a result of nonsense mutations or small out-of-frame insertions or deletions, whereas seven were missense mutations. This brings the total number of distinct ITGB4 mutations to 33. The mutation database indicates that premature termination codons are associated predominantly with the lethal EB-PA variants, whereas missense mutations are more prevalent in nonlethal forms. However, the consequences of the missense mutations are position dependent, and substitutions of highly conserved amino acids may have lethal consequences. In general, indirect immunofluorescence studies of affected skin revealed negative staining for beta 4 integrin in lethal cases and positive, but attenuated, staining in nonlethal cases and correlated with clinical phenotype. The data on specific mutations in EB-PA patients allows prenatal testing and preimplantation genetic diagnosis in families at risk.

Clinical and Genetic Spectrum of Bartter Syndrome Type 3.

PubMed

Seys, Elsa; Andrini, Olga; Keck, Mathilde; Mansour-Hendili, Lamisse; Courand, Pierre-Yves; Simian, Christophe; Deschenes, Georges; Kwon, Theresa; Bertholet-Thomas, Aurélia; Bobrie, Guillaume; Borde, Jean Sébastien; Bourdat-Michel, Guylhène; Decramer, Stéphane; Cailliez, Mathilde; Krug, Pauline; Cozette, Paul; Delbet, Jean Daniel; Dubourg, Laurence; Chaveau, Dominique; Fila, Marc; Jourde-Chiche, Noémie; Knebelmann, Bertrand; Lavocat, Marie-Pierre; Lemoine, Sandrine; Djeddi, Djamal; Llanas, Brigitte; Louillet, Ferielle; Merieau, Elodie; Mileva, Maria; Mota-Vieira, Luisa; Mousson, Christiane; Nobili, François; Novo, Robert; Roussey-Kesler, Gwenaëlle; Vrillon, Isabelle; Walsh, Stephen B; Teulon, Jacques; Blanchard, Anne; Vargas-Poussou, Rosa

2017-08-01

Bartter syndrome type 3 is a clinically heterogeneous hereditary salt-losing tubulopathy caused by mutations of the chloride voltage-gated channel Kb gene ( CLCNKB ), which encodes the ClC-Kb chloride channel involved in NaCl reabsorption in the renal tubule. To study phenotype/genotype correlations, we performed genetic analyses by direct sequencing and multiplex ligation-dependent probe amplification and retrospectively analyzed medical charts for 115 patients with CLCNKB mutations. Functional analyses were performed in Xenopus laevis oocytes for eight missense and two nonsense mutations. We detected 60 mutations, including 27 previously unreported mutations. Among patients, 29.5% had a phenotype of ante/neonatal Bartter syndrome (polyhydramnios or diagnosis in the first month of life), 44.5% had classic Bartter syndrome (diagnosis during childhood, hypercalciuria, and/or polyuria), and 26.0% had Gitelman-like syndrome (fortuitous discovery of hypokalemia with hypomagnesemia and/or hypocalciuria in childhood or adulthood). Nine of the ten mutations expressed in vitro decreased or abolished chloride conductance. Severe (large deletions, frameshift, nonsense, and essential splicing) and missense mutations resulting in poor residual conductance were associated with younger age at diagnosis. Electrolyte supplements and indomethacin were used frequently to induce catch-up growth, with few adverse effects. After a median follow-up of 8 (range, 1-41) years in 77 patients, chronic renal failure was detected in 19 patients (25%): one required hemodialysis and four underwent renal transplant. In summary, we report a genotype/phenotype correlation for Bartter syndrome type 3: complete loss-of-function mutations associated with younger age at diagnosis, and CKD was observed in all phenotypes. Copyright © 2017 by the American Society of Nephrology.

The Qatar genome project: translation of whole-genome sequencing into clinical practice.

PubMed

Zayed, Hatem

2016-10-01

Qatar Genome Project was launched in 2013 with the intent to sequence the genome of each Qatari citizen in an effort to protect Qataris from the high rate of indigenous genetic diseases by allowing the mapping of disease-causing variants/rare variants and establishing a Qatari reference genome. Indeed, this project is expected to have numerous global benefits because the elevated homogeneity of the Qatari population, that will make Qatar an excellent genetic laboratory that will generate a wealth of data that will allow us to make sense of the genotype-phenotype correlations of many diseases, especially the complex multifactorial diseases, and will pave the way for changing the traditional medical practice of looking first at the phenotype rather than the genotype. © 2016 John Wiley & Sons Ltd.

Elevated temperature is more effective than elevated [CO2 ] in exposing genotypic variation in Telopea speciosissima growth plasticity: implications for woody plant populations under climate change.

PubMed

Huang, Guomin; Rymer, Paul D; Duan, Honglang; Smith, Renee A; Tissue, David T

2015-10-01

Intraspecific variation in phenotypic plasticity is a critical determinant of plant species capacity to cope with climate change. A long-standing hypothesis states that greater levels of environmental variability will select for genotypes with greater phenotypic plasticity. However, few studies have examined how genotypes of woody species originating from contrasting environments respond to multiple climate change factors. Here, we investigated the main and interactive effects of elevated [CO2 ] (CE ) and elevated temperature (TE ) on growth and physiology of Coastal (warmer, less variable temperature environment) and Upland (cooler, more variable temperature environment) genotypes of an Australian woody species Telopea speciosissima. Both genotypes were positively responsive to CE (35% and 29% increase in whole-plant dry mass and leaf area, respectively), but only the Coastal genotype exhibited positive growth responses to TE . We found that the Coastal genotype exhibited greater growth response to TE (47% and 85% increase in whole-plant dry mass and leaf area, respectively) when compared with the Upland genotype (no change in dry mass or leaf area). No intraspecific variation in physiological plasticity was detected under CE or TE , and the interactive effects of CE and TE on intraspecific variation in phenotypic plasticity were also largely absent. Overall, TE was a more effective climate factor than CE in exposing genotypic variation in our woody species. Our results contradict the paradigm that genotypes from more variable climates will exhibit greater phenotypic plasticity in future climate regimes. © 2015 John Wiley & Sons Ltd.

URINARY MUTAGENESIS AS AN EXPOSURE BIOMARKER OF COOKED-MEAT-ASSOCIATED MUTAGENS: INFLUENCE OF COOKING TEMPERATURE, PHENOTYPE, AND GENOTYPE IN A CONTROLLED METABOLIC FEEDING STUDY

EPA Science Inventory

ABSTRACT
We evaluated urinary mutagenicity and selected phenotypes and genotypes in 60 subjects in a metabolic feeding study in which meat cooked at low temperature (100oC) was consumed for 1 week followed by meat cooked at high temperature (250oC) the second week. Meat coo...

Phenotypic Diversification Is Associated with Host-Induced Transposon Derepression in the Sudden Oak Death Pathogen Phytophthora ramorum

PubMed Central

Kasuga, Takao; Kozanitas, Melina; Bui, Mai; Hüberli, Daniel; Rizzo, David M.; Garbelotto, Matteo

2012-01-01

The oomycete pathogen Phytophthora ramorum is responsible for sudden oak death (SOD) in California coastal forests. P. ramorum is a generalist pathogen with over 100 known host species. Three or four closely related genotypes of P. ramorum (from a single lineage) were originally introduced in California forests and the pathogen reproduces clonally. Because of this the genetic diversity of P. ramorum is extremely low in Californian forests. However, P. ramorum shows diverse phenotypic variation in colony morphology, colony senescence, and virulence. In this study, we show that phenotypic variation among isolates is associated with the host species from which the microbe was originally cultured. Microarray global mRNA profiling detected derepression of transposable elements (TEs) and down-regulation of crinkler effector homologs (CRNs) in the majority of isolates originating from coast live oak (Quercus agrifolia), but this expression pattern was not observed in isolates from California bay laurel (Umbellularia californica). In some instances, oak and bay laurel isolates originating from the same geographic location had identical genotypes based on multilocus simples sequence repeat (SSR) marker analysis but had different phenotypes. Expression levels of the two marker genes analyzed by quantitative reverse transcription PCR were correlated with originating host species, but not with multilocus genotypes. Because oak is a nontransmissive dead-end host for P. ramorum, our observations are congruent with an epi-transposon hypothesis; that is, physiological stress is triggered on P. ramorum while colonizing oak stems and disrupts epigenetic silencing of TEs. This then results in TE reactivation and possibly genome diversification without significant epidemiological consequences. We propose the P. ramorum-oak host system in California forests as an ad hoc model for epi-transposon mediated diversification. PMID:22529930

SLC24A5 and ASIP as phenotypic predictors in Brazilian population for forensic purposes.

PubMed

Lima, F A; de Araújo Lima, Felícia; Gonçalves, F T; de Toledo Gonçalves, Fernanda; Fridman, C; Fridman, Cintia

2015-07-01

Pigmentation is a variable and complex trait in humans and it is determined by the interaction of environmental factors, age, disease, hormones, exposure to ultraviolet radiation and genetic factors, including pigmentation genes. Many polymorphisms of these genes have been associated with phenotypic diversity of skin, eyes and hair color in homogeneous populations. Phenotype prediction from biological samples using genetic information has benefited forensic area in some countries, leading some criminal investigations. Herein, we evaluated the association between polymorphisms in the genes SLC24A5 (rs1426654) and ASIP (rs6058017) with skin, eyes and hair colors, in 483 healthy individuals from Brazilian population for attainable use in forensic practice. The volunteers answered a questionnaire where they self-reported their skin, eye and hair colors. The polymorphic homozygous genotype of rs1426654∗A and rs6058017∗A in SLC24A5 and ASIP respectively, showed strongest association with fairer skin (OR 47.8; CI 14.1-161.6 and OR 8.6; CI 2.5-29.8); SLC24A5 alone showed associations with blue eyes (OR 20.7; CI 1.2-346.3) and blond hair (OR 26.6; CI 1.5-460.9). Our data showed that polymorphic genotypes (AA), in both genes, are correlated with characteristics of light pigmentation, while the ancestral genotype (GG) is related to darker traits, corroborating with previous studies in European and African populations. These associations show that specific molecular information of an individual may be useful to access some phenotypic features in an attempt to help forensic investigations, not only on crime scene samples but also in cases of face reconstructions in unknown bodies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Cookie-Ases: Interactive Models for Teaching Genotype-Phenotype Relationships

ERIC Educational Resources Information Center

Seipelt, Rebecca L.

2006-01-01

Several hands-on and wet laboratory activities have been proposed to model the genetic concepts of genotypes and phenotypes and their relationship. The exercise presented in this article is a novel, time effective, student-centered, role-playing activity in which students learn about the intricate connection between genotype and phenotype by…

Phenotypic and genotypic detection of Candida albicans and Candida dubliniensis strains isolated from oral mucosa of AIDS pediatric patients

PubMed Central

Livério, Harisson Oliveira; Ruiz, Luciana da Silva; de Freitas, Roseli Santos; Nishikaku, Angela; de Souza, Ana Clara; Paula, Claudete Rodrigues; Domaneschi, Carina

2017-01-01

ABSTRACT The aim of this study was to assess a collection of yeasts to verify the presence of Candida dubliniensis among strains isolated from the oral mucosa of AIDS pediatric patients which were initially characterized as Candida albicans by the traditional phenotypic method, as well as to evaluate the main phenotypic methods used in the discrimination between the two species and confirm the identification through genotypic techniques, i.e., DNA sequencing. Twenty-nine samples of C. albicans isolated from this population and kept in a fungi collection were evaluated and re-characterized. In order to differentiate the two species, phenotypic tests (Thermotolerance tests, Chromogenic medium, Staib agar, Tobacco agar, Hypertonic medium) were performed and genotypic techniques using DNA sequencing were employed for confirmation of isolated species. Susceptibility and specificity were calculated for each test. No phenotypic test alone was sufficient to provide definitive identification of C. dubliniensis or C. albicans, as opposed to results of molecular tests. After amplification and sequencing of specific regions of the 29 studied strains, 93.1% of the isolates were identified as C. albicans and 6.9% as C. dubliniensis. The Staib agar assay showed a higher susceptibility (96.3%) in comparison with other phenotypic techniques. Therefore, genotypic methods are indispensable for the conclusive identification and differentiation between these species. PMID:28423089

Phenotypic and genotypic detection of Candida albicans and Candida dubliniensis strains isolated from oral mucosa of AIDS pediatric patients.

PubMed

Livério, Harisson Oliveira; Ruiz, Luciana da Silva; Freitas, Roseli Santos de; Nishikaku, Angela; Souza, Ana Clara de; Paula, Claudete Rodrigues; Domaneschi, Carina

2017-04-13

The aim of this study was to assess a collection of yeasts to verify the presence of Candida dubliniensis among strains isolated from the oral mucosa of AIDS pediatric patients which were initially characterized as Candida albicans by the traditional phenotypic method, as well as to evaluate the main phenotypic methods used in the discrimination between the two species and confirm the identification through genotypic techniques, i.e., DNA sequencing. Twenty-nine samples of C. albicans isolated from this population and kept in a fungi collection were evaluated and re-characterized. In order to differentiate the two species, phenotypic tests (Thermotolerance tests, Chromogenic medium, Staib agar, Tobacco agar, Hypertonic medium) were performed and genotypic techniques using DNA sequencing were employed for confirmation of isolated species. Susceptibility and specificity were calculated for each test. No phenotypic test alone was sufficient to provide definitive identification of C. dubliniensis or C. albicans, as opposed to results of molecular tests. After amplification and sequencing of specific regions of the 29 studied strains, 93.1% of the isolates were identified as C. albicans and 6.9% as C. dubliniensis. The Staib agar assay showed a higher susceptibility (96.3%) in comparison with other phenotypic techniques. Therefore, genotypic methods are indispensable for the conclusive identification and differentiation between these species.

Associations between anti-microbial resistance phenotypes, anti-microbial resistance genotypes and virulence genes of Escherichia coli isolates from Pakistan and China.

PubMed

Yaqoob, M; Wang, L P; Wang, S; Hussain, S; Memon, J; Kashif, J; Lu, C-P

2013-10-01

The objective of this study was to determine the association between phenotypic resistance, genotypic resistance and virulence genes of Escherichia coli isolates in Jiangsu province, China and Punjab province Pakistan. A total of 62 E. coli isolates were characterized for phenotypic resistance, genotypic resistance and virulence factor genes. The anti-microbial resistance phenotype and genotypes in relation to virulence factor genes were assessed by statistical analysis. Of 20 tested virulence genes, twelve were found and eight were not found in any isolates. sitA and TspE4C2 were the most prevalent virulence genes. Of the 13 anti-microbial agents tested, resistance to ampicillin, sulphonamide and tetracycline was the most frequent. All isolates were multiresistant, and 74% were resistant to trimethoprim and sulphamethaxazole. Phenotypically, tetracycline-, cefotaxime- and trimethoprim-resistant isolates had increased virulence factors as compared with susceptible isolates. Genotypically, resistant genes Tem, ctx-M, Tet, Sul 1, dhfr1, Cat2 and flo-R showed the association with the virulence genes. Almost all classes of anti-microbial-resistant genes have a high association with virulence. Resistant isolates have more virulent genes than the susceptible isolates. © 2012 Blackwell Verlag GmbH.

Identification of homogeneous genetic architecture of multiple genetically correlated traits by block clustering of genome-wide associations.

PubMed

Gupta, Mayetri; Cheung, Ching-Lung; Hsu, Yi-Hsiang; Demissie, Serkalem; Cupples, L Adrienne; Kiel, Douglas P; Karasik, David

2011-06-01

Genome-wide association studies (GWAS) using high-density genotyping platforms offer an unbiased strategy to identify new candidate genes for osteoporosis. It is imperative to be able to clearly distinguish signal from noise by focusing on the best phenotype in a genetic study. We performed GWAS of multiple phenotypes associated with fractures [bone mineral density (BMD), bone quantitative ultrasound (QUS), bone geometry, and muscle mass] with approximately 433,000 single-nucleotide polymorphisms (SNPs) and created a database of resulting associations. We performed analysis of GWAS data from 23 phenotypes by a novel modification of a block clustering algorithm followed by gene-set enrichment analysis. A data matrix of standardized regression coefficients was partitioned along both axes--SNPs and phenotypes. Each partition represents a distinct cluster of SNPs that have similar effects over a particular set of phenotypes. Application of this method to our data shows several SNP-phenotype connections. We found a strong cluster of association coefficients of high magnitude for 10 traits (BMD at several skeletal sites, ultrasound measures, cross-sectional bone area, and section modulus of femoral neck and shaft). These clustered traits were highly genetically correlated. Gene-set enrichment analyses indicated the augmentation of genes that cluster with the 10 osteoporosis-related traits in pathways such as aldosterone signaling in epithelial cells, role of osteoblasts, osteoclasts, and chondrocytes in rheumatoid arthritis, and Parkinson signaling. In addition to several known candidate genes, we also identified PRKCH and SCNN1B as potential candidate genes for multiple bone traits. In conclusion, our mining of GWAS results revealed the similarity of association results between bone strength phenotypes that may be attributed to pleiotropic effects of genes. This knowledge may prove helpful in identifying novel genes and pathways that underlie several correlated phenotypes, as well as in deciphering genetic and phenotypic modularity underlying osteoporosis risk. Copyright © 2011 American Society for Bone and Mineral Research.

Inheritance in a Diallel Crossing Experiment with Longleaf Pine

Treesearch

E. B. Snyder; Gene Namkoong

1978-01-01

Seven-year-old progeny from crosses among 13 randomly selected parent trees provided genetic information on 51 growth, form, foliage, branch, bud, and pest resistance traits. Presented are he&abilities, phenotypic and genotypic variances, covariances, General Combining Ability (GCA), Specific Combining Ability (SCA), and environmental. correlations for all measured...

Genes for Hereditary Sensory and Autonomic Neuropathies: A Genotype-Phenotype Correlation

ERIC Educational Resources Information Center

Rotthier, Annelies; Baets, Jonathan; De Vriendt, Els; Jacobs, An; Auer-Grumbach, Michaela; Levy, Nicolas; Bonello-Palot, Nathalie; Kilic, Sara Sebnem; Weis, Joachim; Nascimento, Andres; Swinkels, Marielle; Kruyt, Moyo C.; Jordanova, Albena; De Jonghe, Peter; Timmerman, Vincent

2009-01-01

Hereditary sensory and autonomic neuropathies (HSAN) are clinically and genetically heterogeneous disorders characterized by axonal atrophy and degeneration, exclusively or predominantly affecting the sensory and autonomic neurons. So far, disease-associated mutations have been identified in seven genes: two genes for autosomal dominant ("SPTLC1"…

UAV-Based Thermal Imaging for High-Throughput Field Phenotyping of Black Poplar Response to Drought

PubMed Central

Ludovisi, Riccardo; Tauro, Flavia; Salvati, Riccardo; Khoury, Sacha; Mugnozza Scarascia, Giuseppe; Harfouche, Antoine

2017-01-01

Poplars are fast-growing, high-yielding forest tree species, whose cultivation as second-generation biofuel crops is of increasing interest and can efficiently meet emission reduction goals. Yet, breeding elite poplar trees for drought resistance remains a major challenge. Worldwide breeding programs are largely focused on intra/interspecific hybridization, whereby Populus nigra L. is a fundamental parental pool. While high-throughput genotyping has resulted in unprecedented capabilities to rapidly decode complex genetic architecture of plant stress resistance, linking genomics to phenomics is hindered by technically challenging phenotyping. Relying on unmanned aerial vehicle (UAV)-based remote sensing and imaging techniques, high-throughput field phenotyping (HTFP) aims at enabling highly precise and efficient, non-destructive screening of genotype performance in large populations. To efficiently support forest-tree breeding programs, ground-truthing observations should be complemented with standardized HTFP. In this study, we develop a high-resolution (leaf level) HTFP approach to investigate the response to drought of a full-sib F2 partially inbred population (termed here ‘POP6’), whose F1 was obtained from an intraspecific P. nigra controlled cross between genotypes with highly divergent phenotypes. We assessed the effects of two water treatments (well-watered and moderate drought) on a population of 4603 trees (503 genotypes) hosted in two adjacent experimental plots (1.67 ha) by conducting low-elevation (25 m) flights with an aerial drone and capturing 7836 thermal infrared (TIR) images. TIR images were undistorted, georeferenced, and orthorectified to obtain radiometric mosaics. Canopy temperature (Tc) was extracted using two independent semi-automated segmentation techniques, eCognition- and Matlab-based, to avoid the mixed-pixel problem. Overall, results showed that the UAV platform-based thermal imaging enables to effectively assess genotype variability under drought stress conditions. Tc derived from aerial thermal imagery presented a good correlation with ground-truth stomatal conductance (gs) in both segmentation techniques. Interestingly, the HTFP approach was instrumental to detect drought-tolerant response in 25% of the population. This study shows the potential of UAV-based thermal imaging for field phenomics of poplar and other tree species. This is anticipated to have tremendous implications for accelerating forest tree genetic improvement against abiotic stress. PMID:29021803

UAV-Based Thermal Imaging for High-Throughput Field Phenotyping of Black Poplar Response to Drought.

PubMed

Ludovisi, Riccardo; Tauro, Flavia; Salvati, Riccardo; Khoury, Sacha; Mugnozza Scarascia, Giuseppe; Harfouche, Antoine

2017-01-01

Poplars are fast-growing, high-yielding forest tree species, whose cultivation as second-generation biofuel crops is of increasing interest and can efficiently meet emission reduction goals. Yet, breeding elite poplar trees for drought resistance remains a major challenge. Worldwide breeding programs are largely focused on intra/interspecific hybridization, whereby Populus nigra L. is a fundamental parental pool. While high-throughput genotyping has resulted in unprecedented capabilities to rapidly decode complex genetic architecture of plant stress resistance, linking genomics to phenomics is hindered by technically challenging phenotyping. Relying on unmanned aerial vehicle (UAV)-based remote sensing and imaging techniques, high-throughput field phenotyping (HTFP) aims at enabling highly precise and efficient, non-destructive screening of genotype performance in large populations. To efficiently support forest-tree breeding programs, ground-truthing observations should be complemented with standardized HTFP. In this study, we develop a high-resolution (leaf level) HTFP approach to investigate the response to drought of a full-sib F 2 partially inbred population (termed here 'POP6'), whose F 1 was obtained from an intraspecific P. nigra controlled cross between genotypes with highly divergent phenotypes. We assessed the effects of two water treatments (well-watered and moderate drought) on a population of 4603 trees (503 genotypes) hosted in two adjacent experimental plots (1.67 ha) by conducting low-elevation (25 m) flights with an aerial drone and capturing 7836 thermal infrared (TIR) images. TIR images were undistorted, georeferenced, and orthorectified to obtain radiometric mosaics. Canopy temperature ( T c ) was extracted using two independent semi-automated segmentation techniques, eCognition- and Matlab-based, to avoid the mixed-pixel problem. Overall, results showed that the UAV platform-based thermal imaging enables to effectively assess genotype variability under drought stress conditions. T c derived from aerial thermal imagery presented a good correlation with ground-truth stomatal conductance ( g s ) in both segmentation techniques. Interestingly, the HTFP approach was instrumental to detect drought-tolerant response in 25% of the population. This study shows the potential of UAV-based thermal imaging for field phenomics of poplar and other tree species. This is anticipated to have tremendous implications for accelerating forest tree genetic improvement against abiotic stress.

Biomass Allocation Patterns Are Linked to Genotypic Differences in Whole-Plant Transpiration Efficiency in Sunflower

PubMed Central

Velázquez, Luciano; Alberdi, Ignacio; Paz, Cosme; Aguirrezábal, Luis

2017-01-01

Increased transpiration efficiency (the ratio of biomass to water transpired, TE) could lead to increased drought tolerance under some water deficit scenarios. Intrinsic (i.e., leaf-level) TE is usually considered as the primary source of variation in whole-plant TE, but empirical data usually contradict this assumption. Sunflower has a significant variability in TE, but a better knowledge of the effect of leaf and plant-level traits could be helpful to obtain more efficient genotypes for water use. The objective of this study was, therefore, to assess if genotypic variation in whole-plant TE is better related to leaf- or plant-level traits. Three experiments were conducted, aimed at verifying the existence of variability in whole-plant TE and whole-plant and leaf-level traits, and to assess their correlation. Sunflower public inbred lines and a segregating population of recombinant inbred lines were grown under controlled conditions and subjected to well-watered and water-deficit treatments. Significant genotypic variation was found for TE and related traits. These differences in whole-plant transpiration efficiency, both between genotypes and between plants within each genotype, showed no association to leaf-level traits, but were significantly and negatively correlated to biomass allocation to leaves and to the ratio of leaf area to total biomass. These associations are likely of a physiological origin, and not only a consequence of genetic linkage in the studied population. These results suggest that genotypic variation for biomass allocation could be potentially exploited as a source for increased transpiration efficiency in sunflower breeding programmes. It is also suggested that phenotyping for TE in this species should not be restricted to leaf-level measurements, but also include measurements of plant-level traits, especially those related to biomass allocation between photosynthetic and non-photosynthetic organs. PMID:29204153

Biomass Allocation Patterns Are Linked to Genotypic Differences in Whole-Plant Transpiration Efficiency in Sunflower.

PubMed

Velázquez, Luciano; Alberdi, Ignacio; Paz, Cosme; Aguirrezábal, Luis; Pereyra Irujo, Gustavo

2017-01-01

Increased transpiration efficiency (the ratio of biomass to water transpired, TE) could lead to increased drought tolerance under some water deficit scenarios. Intrinsic (i.e., leaf-level) TE is usually considered as the primary source of variation in whole-plant TE, but empirical data usually contradict this assumption. Sunflower has a significant variability in TE, but a better knowledge of the effect of leaf and plant-level traits could be helpful to obtain more efficient genotypes for water use. The objective of this study was, therefore, to assess if genotypic variation in whole-plant TE is better related to leaf- or plant-level traits. Three experiments were conducted, aimed at verifying the existence of variability in whole-plant TE and whole-plant and leaf-level traits, and to assess their correlation. Sunflower public inbred lines and a segregating population of recombinant inbred lines were grown under controlled conditions and subjected to well-watered and water-deficit treatments. Significant genotypic variation was found for TE and related traits. These differences in whole-plant transpiration efficiency, both between genotypes and between plants within each genotype, showed no association to leaf-level traits, but were significantly and negatively correlated to biomass allocation to leaves and to the ratio of leaf area to total biomass. These associations are likely of a physiological origin, and not only a consequence of genetic linkage in the studied population. These results suggest that genotypic variation for biomass allocation could be potentially exploited as a source for increased transpiration efficiency in sunflower breeding programmes. It is also suggested that phenotyping for TE in this species should not be restricted to leaf-level measurements, but also include measurements of plant-level traits, especially those related to biomass allocation between photosynthetic and non-photosynthetic organs.

Diversity of Staphylococcus aureus strains colonizing various niches of the human body.

PubMed

Muenks, Carol E; Hogan, Patrick G; Wang, Jeffrey W; Eisenstein, Kimberly A; Burnham, Carey-Ann D; Fritz, Stephanie A

2016-06-01

As individuals may be colonized with multiple strains of Staphylococcus aureus at different body sites, the objectives of this study were to determine whether S. aureus polyclonal colonization exists within one body niche and the optimal sampling sites and culture methodology to capture the diversity of S. aureus strains in community-dwelling individuals. Swabs were collected from the nares, axillae, and inguinal folds of 3 children with community-associated S. aureus infections and 11 household contacts, all with known S. aureus colonization. S. aureus isolates were recovered from each body niche using 4 culture methods and evaluated for polyclonality using phenotypic and genotypic strain characterization methodologies. Within individuals, the mean (range) number of phenotypes and genotypes was 2.4 (1-4) and 3.1 (1-6), respectively. Six (43%) and 10 (71%) participants exhibited phenotypic and genotypic polyclonality within one body niche, respectively. Broth enrichment yielded the highest analytical sensitivity for S. aureus recovery, while direct plating to blood agar yielded the highest genotypic strain diversity. This study revealed S. aureus polyclonality within a single body niche. Culture methodology and sampling sites influenced the analytical sensitivity of S. aureus colonization detection and the robustness of phenotypic and genotypic strain recovery. Copyright © 2016 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Genotype-by-environment interactions leads to variable selection on life-history strategy in Common Evening Primrose (Oenothera biennis).

PubMed

Johnson, M T J

2007-01-01

Monocarpic plant species, where reproduction is fatal, frequently exhibit variation in the length of their prereproductive period prior to flowering. If this life-history variation in flowering strategy has a genetic basis, genotype-by-environment interactions (G x E) may maintain phenotypic diversity in flowering strategy. The native monocarpic plant Common Evening Primrose (Oenothera biennis L., Onagraceae) exhibits phenotypic variation for annual vs. biennial flowering strategies. I tested whether there was a genetic basis to variation in flowering strategy in O. biennis, and whether environmental variation causes G x E that imposes variable selection on flowering strategy. In a field experiment, I randomized more than 900 plants from 14 clonal families (genotypes) into five distinct habitats that represented a natural productivity gradient. G x E strongly affected the lifetime fruit production of O. biennis, with the rank-order in relative fitness of genotypes changing substantially between habitats. I detected genetic variation in annual vs. biennial strategies in most habitats, as well as a G x E effect on flowering strategy. This variation in flowering strategy was correlated with genetic variation in relative fitness, and phenotypic and genotypic selection analyses revealed that environmental variation resulted in variable directional selection on annual vs. biennial strategies. Specifically, a biennial strategy was favoured in moderately productive environments, whereas an annual strategy was favoured in low-productivity environments. These results highlight the importance of variable selection for the maintenance of genetic variation in the life-history strategy of a monocarpic plant.

MYH9-related disease: a novel prognostic model to predict the clinical evolution of the disease based on genotype-phenotype correlations.

PubMed

Pecci, Alessandro; Klersy, Catherine; Gresele, Paolo; Lee, Kieran J D; De Rocco, Daniela; Bozzi, Valeria; Russo, Giovanna; Heller, Paula G; Loffredo, Giuseppe; Ballmaier, Matthias; Fabris, Fabrizio; Beggiato, Eloise; Kahr, Walter H A; Pujol-Moix, Nuria; Platokouki, Helen; Van Geet, Christel; Noris, Patrizia; Yerram, Preethi; Hermans, Cedric; Gerber, Bernhard; Economou, Marina; De Groot, Marco; Zieger, Barbara; De Candia, Erica; Fraticelli, Vincenzo; Kersseboom, Rogier; Piccoli, Giorgina B; Zimmermann, Stefanie; Fierro, Tiziana; Glembotsky, Ana C; Vianello, Fabrizio; Zaninetti, Carlo; Nicchia, Elena; Güthner, Christiane; Baronci, Carlo; Seri, Marco; Knight, Peter J; Balduini, Carlo L; Savoia, Anna

2014-02-01

MYH9-related disease (MYH9-RD) is a rare autosomal-dominant disorder caused by mutations in the gene for nonmuscle myosin heavy chain IIA (NMMHC-IIA). MYH9-RD is characterized by a considerable variability in clinical evolution: patients present at birth with only thrombocytopenia, but some of them subsequently develop sensorineural deafness, cataract, and/or nephropathy often leading to end-stage renal disease (ESRD). We searched for genotype-phenotype correlations in the largest series of consecutive MYH9-RD patients collected so far (255 cases from 121 families). Association of genotypes with noncongenital features was assessed by a generalized linear regression model. The analysis defined disease evolution associated to seven different MYH9 genotypes that are responsible for 85% of MYH9-RD cases. Mutations hitting residue R702 demonstrated a complete penetrance for early-onset ESRD and deafness. The p.D1424H substitution associated with high risk of developing all the noncongenital manifestations of disease. Mutations hitting a distinct hydrophobic seam in the NMMHC-IIA head domain or substitutions at R1165 associated with high risk of deafness but low risk of nephropathy or cataract. Patients with p.E1841K, p.D1424N, and C-terminal deletions had low risk of noncongenital defects. These findings are essential to patients' clinical management and genetic counseling and are discussed in view of molecular pathogenesis of MYH9-RD. © 2013 WILEY PERIODICALS, INC.

The Face of Noonan Syndrome: Does Phenotype Predict Genotype

PubMed Central

Allanson, Judith E.; Bohring, Axel; Dorr, Helmuth-Guenther; Dufke, Andreas; Gillessen-Kaesbach, Gabrielle; Horn, Denise; König, Rainer; Kratz, Christian P.; Kutsche, Kerstin; Pauli, Silke; Raskin, Salmo; Rauch, Anita; Turner, Anne; Wieczorek, Dagmar; Zenker, Martin

2011-01-01

The facial photographs of 81 individuals with Noonan syndrome, from infancy to adulthood, have been evaluated by two dysmorphologists (JA and MZ), each of whom has considerable experience with disorders of the Ras/MAPK pathway. Thirty-two of this cohort have PTPN11 mutations, 21 SOS1 mutations, 11 RAF1 mutations, and 17 KRAS mutations. The facial appearance of each person was judged to be typical of Noonan syndrome or atypical. In each gene category both typical and unusual faces were found. We determined that some individuals with mutations in the most commonly affected gene, PTPN11, which is correlated with the cardinal physical features, may have a quite atypical face. Conversely, some individuals with KRAS mutations, which may be associated with a less characteristic intellectual phenotype and a resemblance to Costello and cardio-facio-cutaneous syndromes, can have a very typical face. Thus, the facial phenotype, alone, is insufficient to predict the genotype, but certain facial features may facilitate an educated guess in some cases. PMID:20602484

Association of Neuropeptide-Y (NPY) and Interleukin-1beta (IL1B), Genotype-Phenotype Correlation and Plasma Lipids with Type-II Diabetes

PubMed Central

Mansuri, Mohmmad Shoab; Ansarullah; Laddha, Naresh C.; Thakker, Ami; Ramachandran, A. V.; Begum, Rasheedunnisa

2016-01-01

Background Neuropeptide Y (NPY) is known to play a role in the regulation of satiety, energy balance, body weight, and insulin release. Interleukin-1beta (IL1B) has been associated with loss of beta-cell mass in type-II diabetes (TIID). Objectives The present study attempts to investigate the association of NPY exon2 +1128 T/C (Leu7Pro; rs16139), NPY promoter -399 T/C (rs16147) and IL1B -511 C/T (rs16944) polymorphisms with TIID and their correlation with plasma lipid levels, BMI, and IL1B transcript levels. Methods PCR-RFLP was used for genotyping these polymorphisms in a case-control study involving 558 TIID patients and 1085 healthy age-matched controls from Gujarat. Linkage disequilibrium and haplotype analysis of the NPY polymorphic sites were performed to assess their association with TIID. IL1B transcript levels in PBMCs were also assessed in 108 controls and 101 patients using real-time PCR. Results Our results show significant association of both structural and promoter polymorphisms of NPY (p<0.0001 and p<0.0001 respectively) in patients with TIID. However, the IL1B C/T polymorphism did not show any association (p = 0.3797) with TIID patients. Haplotype analysis revealed more frequent association of CC and CT haplotypes (p = 3.34 x 10−5, p = 6.04 x 10−9) in diabetics compared to controls and increased the risk of diabetes by 3.02 and 2.088 respectively. Transcript levels of IL1B were significantly higher (p<0.0001) in patients as compared to controls. Genotype-phenotype correlation of IL1B polymorphism did not show any association with its higher transcript levels. In addition, NPY +1128 T/C polymorphism was found to be associated with increased plasma LDL levels (p = 0.01). Conclusion The present study provides an evidence for a strong correlation between structural and promoter polymorphisms of NPY gene and upregulation of IL1B transcript levels with susceptibility to TIID and altering the lipid metabolism in Gujarat population. PMID:27749914

Association of Neuropeptide-Y (NPY) and Interleukin-1beta (IL1B), Genotype-Phenotype Correlation and Plasma Lipids with Type-II Diabetes.

PubMed

Patel, Roma; Dwivedi, Mitesh; Mansuri, Mohmmad Shoab; Ansarullah; Laddha, Naresh C; Thakker, Ami; Ramachandran, A V; Begum, Rasheedunnisa

2016-01-01

Neuropeptide Y (NPY) is known to play a role in the regulation of satiety, energy balance, body weight, and insulin release. Interleukin-1beta (IL1B) has been associated with loss of beta-cell mass in type-II diabetes (TIID). The present study attempts to investigate the association of NPY exon2 +1128 T/C (Leu7Pro; rs16139), NPY promoter -399 T/C (rs16147) and IL1B -511 C/T (rs16944) polymorphisms with TIID and their correlation with plasma lipid levels, BMI, and IL1B transcript levels. PCR-RFLP was used for genotyping these polymorphisms in a case-control study involving 558 TIID patients and 1085 healthy age-matched controls from Gujarat. Linkage disequilibrium and haplotype analysis of the NPY polymorphic sites were performed to assess their association with TIID. IL1B transcript levels in PBMCs were also assessed in 108 controls and 101 patients using real-time PCR. Our results show significant association of both structural and promoter polymorphisms of NPY (p<0.0001 and p<0.0001 respectively) in patients with TIID. However, the IL1B C/T polymorphism did not show any association (p = 0.3797) with TIID patients. Haplotype analysis revealed more frequent association of CC and CT haplotypes (p = 3.34 x 10-5, p = 6.04 x 10-9) in diabetics compared to controls and increased the risk of diabetes by 3.02 and 2.088 respectively. Transcript levels of IL1B were significantly higher (p<0.0001) in patients as compared to controls. Genotype-phenotype correlation of IL1B polymorphism did not show any association with its higher transcript levels. In addition, NPY +1128 T/C polymorphism was found to be associated with increased plasma LDL levels (p = 0.01). The present study provides an evidence for a strong correlation between structural and promoter polymorphisms of NPY gene and upregulation of IL1B transcript levels with susceptibility to TIID and altering the lipid metabolism in Gujarat population.

Functional analysis of mutations in SLC7A9, and genotype-phenotype correlation in non-Type I cystinuria.

PubMed

Font, M A; Feliubadaló, L; Estivill, X; Nunes, V; Golomb, E; Kreiss, Y; Pras, E; Bisceglia, L; d'Adamo, A P; Zelante, L; Gasparini, P; Bassi, M T; George , A L; Manzoni, M; Riboni, M; Ballabio, A; Borsani, G; Reig, N; Fernández, E; Zorzano, A; Bertran, J; Palacín, M

2001-02-15

Cystinuria (OMIM 220100) is a common recessive disorder of renal reabsorption of cystine and dibasic amino acids that results in nephrolithiasis of cystine. Mutations in SLC3A1, which encodes rBAT, cause Type I cystinuria, and mutations in SLC7A9, which encodes a putative subunit of rBAT (b(o,+)AT), cause non-Type I cystinuria. Here we describe the genomic structure of SLC7A9 (13 exons) and 28 new mutations in this gene that, together with the seven previously reported, explain 79% of the alleles in 61 non-Type I cystinuria patients. These data demonstrate that SLC7A9 is the main non-Type I cystinuria gene. Mutations G105R, V170M, A182T and R333W are the most frequent SLC7A9 missense mutations found. Among heterozygotes carrying these mutations, A182T heterozygotes showed the lowest urinary excretion values of cystine and dibasic amino acids. Functional analysis of mutation A182T after co-expression with rBAT in HeLa cells revealed significant residual transport activity. In contrast, mutations G105R, V170M and R333W are associated to a complete or almost complete loss of transport activity, leading to a more severe urinary phenotype in heterozygotes. SLC7A9 mutations located in the putative transmembrane domains of b(o,+)AT and affecting conserved amino acid residues with a small side chain generate a severe phenotype, while mutations in non-conserved residues give rise to a mild phenotype. These data provide the first genotype-phenotype correlation in non-Type I cystinuria, and show that a mild urinary phenotype in heterozygotes may associate with mutations with significant residual transport activity.

Combining ability, heritability and genotypic relations of different physiological traits in cacao hybrids

PubMed Central

de Almeida, Alex-Alan Furtado; Branco, Márcia Christina da Silva; Costa, Marcio Gilberto Cardoso; Ahnert, Dario

2017-01-01

Selecting parents and evaluating progenies is a very important step in breeding programs and involves approaches such as understanding the initial stages of growth and characterizing the variability among genotypes for different parameters, such as physiological, growth, biomass partitioning and nutrient translocation to the aerial part. In these cases, facilitating tools can be used to understand the involved gene dynamics, such as diallel crosses and genetic and phenotypic correlations. Our main hypothesis is that the contrasting phenotypes of these parental genotypes of cocoa used are due to genetic factors, and progenies derived from crosses of these parental genotypes are useful for breeding programs related to plant architecture, physiological parameters and translocation of mineral nutrients. We aimed to evaluate the combining abilities in progenies of cacao (Theobroma cacao L) originating from contrasting parents for canopy vigor. Emphasis was given to the evaluation of morphological and physiological parameters and the phenotypic and genotypic correlations to understand the dynamics of the action of the genes involved, as well as in expression profile from genes of gibberellins biosynthesis pathway in the parents. Fifteen F1 progenies were obtained from crosses of six clones (IMC 67, P4B, PUCALA, SCA 6, SCA 24 and SJ 02) that were evaluated in a randomized complete block design with four replicates of 12 plants per progeny, in a balanced half table diallel scheme. It is possible to identify and select plants and progenies of low, medium and high height, as there is expressive genetic variability for the evaluated parameters, some of these on higher additive effects, others on larger nonadditive effects and others under a balance of these effects. Most physiological parameters evaluated show that for selection of plants with the desired performance, no complex breeding methods would be necessary due to the high and medium heritability observed. Strong genetic components were observed from many of the correlations, which indicate the possibility to formulate selection indices for multi-traits, such as dwarfism or semidwarfism, tolerance to increase of leaf sodium concentrations and maintenance of the photosynthetic apparatus integrity under these conditions. Additionally, plants with higher carbon fixation, better water use, higher carboxylation efficiency and greater magnesium accumulation in leaves can be selected. PMID:28628670

Combining ability, heritability and genotypic relations of different physiological traits in cacao hybrids.

PubMed

Pereira, Allan Silva; de Almeida, Alex-Alan Furtado; Branco, Márcia Christina da Silva; Costa, Marcio Gilberto Cardoso; Ahnert, Dario

2017-01-01

Selecting parents and evaluating progenies is a very important step in breeding programs and involves approaches such as understanding the initial stages of growth and characterizing the variability among genotypes for different parameters, such as physiological, growth, biomass partitioning and nutrient translocation to the aerial part. In these cases, facilitating tools can be used to understand the involved gene dynamics, such as diallel crosses and genetic and phenotypic correlations. Our main hypothesis is that the contrasting phenotypes of these parental genotypes of cocoa used are due to genetic factors, and progenies derived from crosses of these parental genotypes are useful for breeding programs related to plant architecture, physiological parameters and translocation of mineral nutrients. We aimed to evaluate the combining abilities in progenies of cacao (Theobroma cacao L) originating from contrasting parents for canopy vigor. Emphasis was given to the evaluation of morphological and physiological parameters and the phenotypic and genotypic correlations to understand the dynamics of the action of the genes involved, as well as in expression profile from genes of gibberellins biosynthesis pathway in the parents. Fifteen F1 progenies were obtained from crosses of six clones (IMC 67, P4B, PUCALA, SCA 6, SCA 24 and SJ 02) that were evaluated in a randomized complete block design with four replicates of 12 plants per progeny, in a balanced half table diallel scheme. It is possible to identify and select plants and progenies of low, medium and high height, as there is expressive genetic variability for the evaluated parameters, some of these on higher additive effects, others on larger nonadditive effects and others under a balance of these effects. Most physiological parameters evaluated show that for selection of plants with the desired performance, no complex breeding methods would be necessary due to the high and medium heritability observed. Strong genetic components were observed from many of the correlations, which indicate the possibility to formulate selection indices for multi-traits, such as dwarfism or semidwarfism, tolerance to increase of leaf sodium concentrations and maintenance of the photosynthetic apparatus integrity under these conditions. Additionally, plants with higher carbon fixation, better water use, higher carboxylation efficiency and greater magnesium accumulation in leaves can be selected.

Evaluating the quality of Marfan genotype-phenotype correlations in existing FBN1 databases.

PubMed

Groth, Kristian A; Von Kodolitsch, Yskert; Kutsche, Kerstin; Gaustadnes, Mette; Thorsen, Kasper; Andersen, Niels H; Gravholt, Claus H

2017-07-01

Genetic FBN1 testing is pivotal for confirming the clinical diagnosis of Marfan syndrome. In an effort to evaluate variant causality, FBN1 databases are often used. We evaluated the current databases regarding FBN1 variants and validated associated phenotype records with a new Marfan syndrome geno-phenotyping tool called the Marfan score. We evaluated four databases (UMD-FBN1, ClinVar, the Human Gene Mutation Database (HGMD), and Uniprot) containing 2,250 FBN1 variants supported by 4,904 records presented in 307 references. The Marfan score calculated for phenotype data from the records quantified variant associations with Marfan syndrome phenotype. We calculated a Marfan score for 1,283 variants, of which we confirmed the database diagnosis of Marfan syndrome in 77.1%. This represented only 35.8% of the total registered variants; 18.5-33.3% (UMD-FBN1 versus HGMD) of variants associated with Marfan syndrome in the databases could not be confirmed by the recorded phenotype. FBN1 databases can be imprecise and incomplete. Data should be used with caution when evaluating FBN1 variants. At present, the UMD-FBN1 database seems to be the biggest and best curated; therefore, it is the most comprehensive database. However, the need for better genotype-phenotype curated databases is evident, and we hereby present such a database.Genet Med advance online publication 01 December 2016.

Primary hyperoxaluria: genotype-phenotype correlation.

PubMed

Pirulli, Doroti; Marangella, Martino; Amoroso, Antonio

2003-01-01

Primary hyperoxaluria type 1 (PH1) is an autosomal recessive disorder caused by a deficiency of alanine-glyoxylate aminotransferase (AGT), which is encoded by a single copy gene (AGXT). Molecular diagnosis was used in conjunction with clinical, biochemical and enzymological data to evaluate genotype-phenotype correlation. Patients can present a severe form of PH1, an adult form and a mild to moderate decrease in renal function. Biochemical diagnosis is made by plasma, urine and dialyzate oxalate and glycolate assays, and by liver AGT activity and pyridoxine responsitivity. Molecular genetic diagnosis can be made using different techniques, for example, the single strand conformation polymorphism technique (SSCP), followed by the sequencing of the 11 AGXT exons. The disease is clinically and genetically classified as highly heterogeneous. Mutant alleles can be recognised in 80- 90% of chromosomes, depending on the techniques used. Mutations in exons 1, 2, 4 and 10 are more frequent in Italian patients. Normalized AGT activity seems to be lower in the severe form than in the adult form. Double heterozygous patients present a lower age at disease onset and they were more frequent in the more severe than in mild severe disease. The 444T>C mutation was more frequent in the severe form, while the opposite was observed for 630G>A. 630G>A mutation homozygotes had a higher AGT residual activity. The presence of allelic heterogeneity of the AGXT could be responsible, to some extent, for the phenotypic heterogeneity in PH1. Homozygous genotypes were more frequent than expected and were associated with a less severe form of the disease.

Clinical, Endocrine, and Molecular Genetic Analysis of a Large Cohort of Saudi Arabian Patients with Laron Syndrome.

PubMed

Al-Ashwal, Abdullah A; Al-Sagheir, Afaf; Ramzan, Khushnooda; Al-Owain, Mohammed; Allam, Rabab; Qari, Alya; Al-Numair, Nouf S; Imtiaz, Faiqa

2017-01-01

Laron syndrome (LS) is an autosomal recessive disease characterized by marked short stature and very low serum IGF-1 and IGFBP-3 levels. This study assessed the clinical and endocrine features alongside determining the growth hormone receptor gene (GHR) mutation in Saudi Arabian patients with LS in order to establish whether or not a genotype/phenotype correlation is evident in this large cohort. A total of 40 Saudi Arabian patients with a suspected diagnosis of LS were recruited and subjected to a full clinical and endocrine investigation together with direct sequencing of the coding regions of the GHR gene. GHR mutations were identified in 34 patients from 22 separate nuclear families. All 34 molecularly confirmed patients had the typical clinical and endocrinological manifestations of LS. Eleven different mutations (9 previously unreported) were detected in this cohort of patients, all inherited in an autosomal recessive homozygous form. No genotype/phenotype correlation was apparent. The identification of pathogenic mutations causing LS will be of tremendous use for the molecular diagnosis of patients in Saudi Arabia and the region in general, with respect to prevention of this disease in the forms of future carrier testing, prenatal testing, premarital screening and preimplantation genetic diagnosis. © 2017 S. Karger AG, Basel.

Blue Genes: An Integrative Laboratory to Differentiate Genetic Transformation from Gene Mutation for Underclassmen

ERIC Educational Resources Information Center

Militello, Kevin T.; Chang, Ming-Mei; Simon, Robert D.; Lazatin, Justine C.

2016-01-01

The ability of students to understand the relationship between genotype and phenotype, and the mechanisms by which genotypes and phenotypes can change is essential for students studying genetics. To this end, we have developed a four-week laboratory called Blue Genes, which is designed to help novice students discriminate between two mechanisms by…

Mining the Human Phenome using Semantic Web Technologies: A Case Study for Type 2 Diabetes

PubMed Central

Pathak, Jyotishman; Kiefer, Richard C.; Bielinski, Suzette J.; Chute, Christopher G.

2012-01-01

The ability to conduct genome-wide association studies (GWAS) has enabled new exploration of how genetic variations contribute to health and disease etiology. However, historically GWAS have been limited by inadequate sample size due to associated costs for genotyping and phenotyping of study subjects. This has prompted several academic medical centers to form “biobanks” where biospecimens linked to personal health information, typically in electronic health records (EHRs), are collected and stored on large number of subjects. This provides tremendous opportunities to discover novel genotype-phenotype associations and foster hypothesis generation. In this work, we study how emerging Semantic Web technologies can be applied in conjunction with clinical and genotype data stored at the Mayo Clinic Biobank to mine the phenotype data for genetic associations. In particular, we demonstrate the role of using Resource Description Framework (RDF) for representing EHR diagnoses and procedure data, and enable federated querying via standardized Web protocols to identify subjects genotyped with Type 2 Diabetes for discovering gene-disease associations. Our study highlights the potential of Web-scale data federation techniques to execute complex queries. PMID:23304343

Mining the human phenome using semantic web technologies: a case study for Type 2 Diabetes.

PubMed

Pathak, Jyotishman; Kiefer, Richard C; Bielinski, Suzette J; Chute, Christopher G

2012-01-01

The ability to conduct genome-wide association studies (GWAS) has enabled new exploration of how genetic variations contribute to health and disease etiology. However, historically GWAS have been limited by inadequate sample size due to associated costs for genotyping and phenotyping of study subjects. This has prompted several academic medical centers to form "biobanks" where biospecimens linked to personal health information, typically in electronic health records (EHRs), are collected and stored on large number of subjects. This provides tremendous opportunities to discover novel genotype-phenotype associations and foster hypothesis generation. In this work, we study how emerging Semantic Web technologies can be applied in conjunction with clinical and genotype data stored at the Mayo Clinic Biobank to mine the phenotype data for genetic associations. In particular, we demonstrate the role of using Resource Description Framework (RDF) for representing EHR diagnoses and procedure data, and enable federated querying via standardized Web protocols to identify subjects genotyped with Type 2 Diabetes for discovering gene-disease associations. Our study highlights the potential of Web-scale data federation techniques to execute complex queries.

The correlation of TAS2R38 gene variants with higher risk for chronic rhinosinusitis in Polish patients.

PubMed

Dżaman, Karolina; Zagor, Mariola; Sarnowska, Elżbieta; Krzeski, Antoni; Kantor, Ireneusz

2016-10-31

Bitter taste receptors (T2Rs), especially T2R38s appear as innovative regulators of innate immunity in the respiratory system. The single nucleotide polymorphisms (SNPs) in TAS2R38 gene may contribute to individual differences in susceptibility to respiratory infections especially chronic rhinosinusitis (CRS). TAS2R38 genotypes distribution varies by geographic region, race and ethnicity. The aim of the preliminary study was the identification of SNPs in TAS2R38 encoding genes in Polish patients with CRS and finding potential correlation with CRS phenotypes. The preliminary study contained 20 CRS patients undergoing functional endoscopic sinus surgery (FESS). Fresh sinus mucosa (SM) was obtained during FESS in CRS patients. Patients were genotyped for TAS2R38 using Sanger method and the genotype occurrences of the clinically recalcitrant CRS cohort was evaluated. Analysis of TAS2R38 expression in SM of CRS patients was performed using immunohistochemistry (IHC). T2R38 was highly expressed in SM of CRS patients. Patients with CRS demonstrated both common genotypes PAV, AVI. The heterozygotes frequency (AVI/PAV) was the highest. The protective genotype (PAV/PAV) was noticed in the lowest frequency and connected with lower average value of CT score compare to AVI/AVI genotypes (p=0.01). The work presented in this study provides the hypothesis that airway bitter T2Rs are an innovative sphere of human respiratory innate protection. TAS2R38 polymorphism may influence the susceptibility to CRS. The AVI haplotypes are an independent risk factors for CRS. Additionally, the bitter taste receptors and related signalling pathways might create an unique group of therapeutic targets to treat CRS.

Orphan missense mutations in the cystic fibrosis transmembrane conductance regulator: A three-step biological approach to establishing a correlation between genotype and phenotype.

PubMed

Fresquet, Fleur; Clement, Romain; Norez, Caroline; Sterlin, Adélaïde; Melin, Patricia; Becq, Frédéric; Kitzis, Alain; Thoreau, Vincent; Bilan, Frédéric

2011-09-01

More than 1860 mutations have been found within the human cystic fibrosis transmembrane conductance regulator (CFTR) gene sequence. These mutations can be classified according to their degree of severity in CF disease. Although the most common mutations are well characterized, few data are available for rare mutations. Thus, genetic counseling is particularly difficult when fetuses or patients with CF present these orphan variations. We describe a three-step in vitro assay that can evaluate rare missense CFTR mutation consequences to establish a correlation between genotype and phenotype. By using a green fluorescent protein-tagged CFTR construct, we expressed mutated proteins in COS-7 cells. CFTR trafficking was visualized by confocal microscopy, and the cellular localization of CFTR was determined using intracellular markers. We studied the CFTR maturation process using Western blot analysis and evaluated CFTR channel activity by automated iodide efflux assays. Of six rare mutations that we studied, five have been isolated in our laboratory. The cellular and functional impact that we observed in each case was compared with the clinical data concerning the patients in whom we encountered these mutations. In conclusion, we propose that performing this type of analysis for orphan CFTR missense mutations can improve CF genetic counseling. Copyright © 2011 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

ACTN3 R577X polymorphism and performance phenotypes in young Chinese male soldiers.

PubMed

Shang, Xuya; Zhang, Fu; Zhang, Li; Huang, Changlin

2012-01-01

Alpha-actinin-3 (ACTN3) is absent in 18% of healthy Caucasian individuals owing to homozygosity for a premature stop codon (X) at amino acid 577 (rs1815739). Previous studies have shown a strong association between ACTN3 genotype and human athletic performance. In a study of 452 young Chinese male soldiers, we examined the distribution of ACTN3 genotypes and alleles and analysed the association between ACTN3 genotypes and athletic performance. We found that the frequencies of the ACTN3 R577X genotype (RR 39.8%, RX 43.4%, and XX 16.8%) and R577X allele (R 61.5%, X 38.5%) in young Chinese males were not significantly different from those in Caucasians. We only observed a significant association (P = 0.025) between ACTN3 R577X genotypes and grip strength. Participants with the XX genotype displayed significantly lower handgrip strength than individuals with the RR genotype (P = 0.021), but the difference between XX and RX means (P = 0.258) and that between RR and RX means (P = 0.42) was not significant. We did not observe a strong association between the ACTN3 R577X genotypes and sprint phenotypes or endurance phenotypes. In conclusion, our results indicate that the ACTN3 R577X polymorphism is most strongly associated with grip strength in young Chinese male soldiers.

Phenotype and genotype in 52 patients with Rubinstein-Taybi syndrome caused by EP300 mutations.

PubMed

Fergelot, Patricia; Van Belzen, Martine; Van Gils, Julien; Afenjar, Alexandra; Armour, Christine M; Arveiler, Benoit; Beets, Lex; Burglen, Lydie; Busa, Tiffany; Collet, Marie; Deforges, Julie; de Vries, Bert B A; Dominguez Garrido, Elena; Dorison, Nathalie; Dupont, Juliette; Francannet, Christine; Garciá-Minaúr, Sixto; Gabau Vila, Elisabeth; Gebre-Medhin, Samuel; Gener Querol, Blanca; Geneviève, David; Gérard, Marion; Gervasini, Cristina Giovanna; Goldenberg, Alice; Josifova, Dragana; Lachlan, Katherine; Maas, Saskia; Maranda, Bruno; Moilanen, Jukka S; Nordgren, Ann; Parent, Philippe; Rankin, Julia; Reardon, Willie; Rio, Marlène; Roume, Joëlle; Shaw, Adam; Smigiel, Robert; Sojo, Amaia; Solomon, Benjamin; Stembalska, Agnieszka; Stumpel, Constance; Suarez, Francisco; Terhal, Paulien; Thomas, Simon; Touraine, Renaud; Verloes, Alain; Vincent-Delorme, Catherine; Wincent, Josephine; Peters, Dorien J M; Bartsch, Oliver; Larizza, Lidia; Lacombe, Didier; Hennekam, Raoul C

2016-12-01

Rubinstein-Taybi syndrome (RSTS) is a developmental disorder characterized by a typical face and distal limbs abnormalities, intellectual disability, and a vast number of other features. Two genes are known to cause RSTS, CREBBP in 60% and EP300 in 8-10% of clinically diagnosed cases. Both paralogs act in chromatin remodeling and encode for transcriptional co-activators interacting with >400 proteins. Up to now 26 individuals with an EP300 mutation have been published. Here, we describe the phenotype and genotype of 42 unpublished RSTS patients carrying EP300 mutations and intragenic deletions and offer an update on another 10 patients. We compare the data to 308 individuals with CREBBP mutations. We demonstrate that EP300 mutations cause a phenotype that typically resembles the classical RSTS phenotype due to CREBBP mutations to a great extent, although most facial signs are less marked with the exception of a low-hanging columella. The limb anomalies are more similar to those in CREBBP mutated individuals except for angulation of thumbs and halluces which is very uncommon in EP300 mutated individuals. The intellectual disability is variable but typically less marked whereas the microcephaly is more common. All types of mutations occur but truncating mutations and small rearrangements are most common (86%). Missense mutations in the HAT domain are associated with a classical RSTS phenotype but otherwise no genotype-phenotype correlation is detected. Pre-eclampsia occurs in 12/52 mothers of EP300 mutated individuals versus in 2/59 mothers of CREBBP mutated individuals, making pregnancy with an EP300 mutated fetus the strongest known predictor for pre-eclampsia. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

High frequency of C9orf72 hexanucleotide repeat expansion in amyotrophic lateral sclerosis patients from two founder populations sharing the same risk haplotype.

PubMed

Goldstein, Orly; Gana-Weisz, Mali; Nefussy, Beatrice; Vainer, Batel; Nayshool, Omri; Bar-Shira, Anat; Traynor, Bryan J; Drory, Vivian E; Orr-Urtreger, Avi

2018-04-01

We characterized the C9orf72 hexanucleotide repeat expansion (RE) mutation in amyotrophic lateral sclerosis (ALS) patients of 2 distinct origins, Ashkenazi and North Africa Jews (AJ, NAJ), its frequency, and genotype-phenotype correlations. In AJ, 80% of familial ALS (fALS) and 11% of sporadic ALS carried the RE, a total of 12.9% of all AJ-ALS compared to 0.3% in AJ controls (odds ratio [OR] = 44.3, p < 0.0001). In NAJ, 10% of fALS and 9% of sporadic ALS carried the RE, a total of 9.1% of all NAJ-ALS compared to 1% in controls (OR = 9.9, p = 0.0006). We identified a risk haplotype shared among all ALS patients, although an association with age at disease onset, fALS, and dementia were observed only in AJ. Variations were identified downstream the repeats. The risk haplotype and these polymorphisms were at high frequencies in alleles with 8 repeats or more, suggesting sequence instability. The different genotype-phenotype correlations and OR, together with the large range in age at onset, suggest that other modifiers and risk factors may affect penetrance and phenotype in ALS. Copyright © 2017 Elsevier Inc. All rights reserved.

Phenotypic changes associated with the fitness cost in antibiotic resistant Escherichia coli strains.

PubMed

Suzuki, Shingo; Horinouchi, Takaaki; Furusawa, Chikara

2016-02-01

the acquisition of antibiotic resistance in bacterial cells is often accompanied with a reduction of fitness in the absence of antibiotics, known as the "fitness cost". The magnitude of this fitness cost is an important biological parameter that influences the degree to which antibiotic resistant strains become widespread. However, the relationship between the fitness cost and comprehensive phenotypic and genotypic changes remains unclear. Here, we quantified the fitness cost of resistant strains obtained by experimental evolution in the presence of various antibiotics, and analyzed how the cost correlated to phenotypic and genotypic changes in the resistant strains. we measured the specific growth rate of the resistant strains in the presence of various concentrations of drugs or in their absence. In the absence of drugs, the resistant strains showed reductions of approximately 20% to 50% in growth rate compared with the parent strain, which corresponded to the fitness cost. We found that the decrease of the specific growth rate was correlated with overall expression changes between the parent and resistant strains, measured by the Euclid distance between expression profiles. We also found that there are a number of genes whose changes in expression levels were significantly correlated with the growth rate, which may account for the observed correlation between the fitness cost and overall expression changes. our analysis provides a basis for quantitative understanding of the mechanism of the fitness cost. This understanding may provide clues on how to influence the fitness cost that accompanies resistance acquisition and consequently how to limit the spread of antibiotic resistant strains.

The prevalence of glucose-6-phosphate dehydrogenase deficiency in Gambian school children.

PubMed

Okebe, Joseph; Amambua-Ngwa, Alfred; Parr, Jason; Nishimura, Sei; Daswani, Melissa; Takem, Ebako N; Affara, Muna; Ceesay, Serign J; Nwakanma, Davis; D'Alessandro, Umberto

2014-04-17

Primaquine, the only available drug effective against Plasmodium falciparum sexual stages, induces also a dose-dependent haemolysis, especially in glucose-6-phosphate dehydrogenase deficient (G6PDd) individuals. Therefore, it is important to determine the prevalence of this deficiency in areas that would potentially benefit from its use. The prevalence of G6PD deficiency by genotype and enzyme activity was determined in healthy school children in The Gambia. Blood samples from primary school children collected during a dry season malaria survey were screened for G6PDd and malaria infection. Genotypes for allele mutations reported in the country; 376, 202A-, 968A- and 542 were analysed while enzyme activity (phenotype) was assayed using a semi-quantitative commercial test kit. Enzyme activity values were fitted in a finite mixture model to determine the distribution and calculate a cut-off for deficiency. The association between genotype and phenotype for boys and girls as well as the association between mutant genotype and deficient phenotype was analysed. Samples from 1,437 children; 51% boys were analysed. The prevalence of P. falciparum malaria infection was 14%. The prevalence of the 202A-, 968 and 542 mutations was 1.8%, 2.1% and 1.0%, respectively, and higher in boys than in girls. The prevalence of G6PDd phenotype was 6.4% (92/1,437), 7.8% (57/728) in boys and 4.9% (35/709) in girls with significantly higher odds in the former (OR 1.64, 95% CI 1.05, 2.53, p = 0.026). The deficient phenotype was associated with reduced odds of malaria infection (OR 0.77, 95% CI 0.36, 1.62, p = 0.49). There is a weak association between genotype and phenotype estimates of G6PDd prevalence. The phenotype expression of deficiency represents combinations of mutant alleles rather than specific mutations. Genotype studies in individuals with a deficient phenotype would help identify alleles responsible for haemolysis.

Genetic parameters and path analysis in cowpea genotypes grown in the Cerrado/Pantanal ecotone.

PubMed

Lopes, K V; Teodoro, P E; Silva, F A; Silva, M T; Fernandes, R L; Rodrigues, T C; Faria, T C; Corrêa, A M

2017-05-18

Estimating genetic parameters in plant breeding allows us to know the population potential for selecting and designing strategies that can maximize the achievement of superior genotypes. The objective of this study was to evaluate the genetic potential of a population of 20 cowpea genotypes by estimating genetic parameters and path analysis among the traits to guide the selection strategies. The trial was conducted in randomized block design with four replications. Its morphophysiological components, components of green grain production and dry grain yield were estimated from genetic use and correlations between the traits. Phenotypic correlations were deployed through path analysis into direct and indirect effects of morphophysiological traits and yield components on dry grain yield. There were significant differences (P < 0.01) between the genotypes for most the traits, indicating the presence of genetic variability in the population and the possibility of practicing selection. The population presents the potential for future genetic breeding studies and is highly promising for the selection of traits dry grain yield, the number of grains per pod, and hundred grains mass. A number of grains per green pod is the main determinant trait of dry grain yield that is also influenced by the cultivar cycle and that the selection for the dry grain yield can be made indirectly by selecting the green pod mass and green pod length.

A targeted genotyping approach enhances identification of variants in taste receptor and appetite/reward genes of potential functional importance for obesity-related porcine traits.

PubMed

Cirera, S; Clop, A; Jacobsen, M J; Guerin, M; Lesnik, P; Jørgensen, C B; Fredholm, M; Karlskov-Mortensen, P

2018-04-01

Taste receptors (TASRs) and appetite and reward (AR) mechanisms influence eating behaviour, which in turn affects food intake and risk of obesity. In a previous study, we used next generation sequencing to identify potentially functional mutations in TASR and AR genes and found indications for genetic associations between identified variants and growth and fat deposition in a subgroup of animals (n = 38) from the UNIK resource pig population. This population was created for studying obesity and obesity-related diseases. In the present study we validated results from our previous study by investigating genetic associations between 24 selected single nucleotide variants in TASR and AR gene variants and 35 phenotypes describing obesity and metabolism in the entire UNIK population (n = 564). Fifteen variants showed significant association with specific obesity-related phenotypes after Bonferroni correction. Six of the 15 genes, namely SIM1, FOS, TAS2R4, TAS2R9, MCHR2 and LEPR, showed good correlation between known biological function and associated phenotype. We verified a genetic association between potentially functional variants in TASR/AR genes and growth/obesity and conclude that the combination of identification of potentially functional variants by next generation sequencing followed by targeted genotyping and association studies is a powerful and cost-effective approach for increasing the power of genetic association studies. © 2018 Stichting International Foundation for Animal Genetics.

The three stages of epilepsy in patients with CDKL5 mutations.

PubMed

Bahi-Buisson, Nadia; Kaminska, Anna; Boddaert, Nathalie; Rio, Marlène; Afenjar, Alexandra; Gérard, Marion; Giuliano, Fabienne; Motte, Jacques; Héron, Delphine; Morel, Marie Ange N'guyen; Plouin, Perrine; Richelme, Christian; des Portes, Vincent; Dulac, Olivier; Philippe, Christophe; Chiron, Catherine; Nabbout, Rima; Bienvenu, Thierry

2008-06-01

Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene are responsible for a severe encephalopathy with early epilepsy. So far, the electroclinical phenotype remains largely unknown and no clear genotype-phenotype correlations have been established. To characterize the epilepsy associated with CDKL5 mutations and to look for a relationship between the genotype and the course of epilepsy. We retrospectively analyzed the electroclinical phenotypes of 12 patients aged from 2.5 to 19 years diagnosed with pathogenic CDKL5 mutations and one patient with a novel intronic sequence variation of uncertain pathogenicity and examined whether the severity of the epilepsy was linked to the type and location of mutations. The epilepsy course reveals three successive stages: (Stage I) early epilepsy (onset 1-10 weeks) with normal interictal electroencephalogram (EEG) (10/13) despite frequent convulsive seizures; (Stage II) epileptic encephalopathy with infantile spasms (8/8) and hypsarrhythmia (8/8). At the age of evaluation, seven patients were seizure free and six had developed refractory epilepsy (stage III) with tonic seizures and myoclonia (5/6). Interestingly, the patients carrying a CDKL5 mutations causing a truncation of the catalytic domain tended to develop a more frequent refractory epilepsy than patients with mutations located downstream (4/6, 66.6% versus 1/6, 16%) although, these trends are not yet significant. Our data contribute to a better definition of the epileptic phenotype in CDKL5 mutations, and might give some clues to a potential relationship between the phenotype and the genotype in these patients.

Contrasting modes and tempos of venom expression evolution in two snake species.

PubMed

Margres, Mark J; McGivern, James J; Seavy, Margaret; Wray, Kenneth P; Facente, Jack; Rokyta, Darin R

2015-01-01

Selection is predicted to drive diversification within species and lead to local adaptation, but understanding the mechanistic details underlying this process and thus the genetic basis of adaptive evolution requires the mapping of genotype to phenotype. Venom is complex and involves many genes, but the specialization of the venom gland toward toxin production allows specific transcripts to be correlated with specific toxic proteins, establishing a direct link from genotype to phenotype. To determine the extent of expression variation and identify the processes driving patterns of phenotypic diversity, we constructed genotype-phenotype maps and compared range-wide toxin-protein expression variation for two species of snake with nearly identical ranges: the eastern diamondback rattlesnake (Crotalus adamanteus) and the eastern coral snake (Micrurus fulvius). We detected significant expression variation in C. adamanteus, identified the specific loci associated with population differentiation, and found that loci expressed at all levels contributed to this divergence. Contrary to expectations, we found no expression variation in M. fulvius, suggesting that M. fulvius populations are not locally adapted. Our results not only linked expression variation at specific loci to divergence in a polygenic, complex trait but also have extensive conservation and biomedical implications. C. adamanteus is currently a candidate for federal listing under the Endangered Species Act, and the loss of any major population would result in the irrevocable loss of a unique venom phenotype. The lack of variation in M. fulvius has significant biomedical application because our data will assist in the development of effective antivenom for this species. Copyright © 2015 by the Genetics Society of America.

Translation of Genotype to Phenotype by a Hierarchy of Cell Subsystems.

PubMed

Yu, Michael Ku; Kramer, Michael; Dutkowski, Janusz; Srivas, Rohith; Licon, Katherine; Kreisberg, Jason; Ng, Cherie T; Krogan, Nevan; Sharan, Roded; Ideker, Trey

2016-02-24

Accurately translating genotype to phenotype requires accounting for the functional impact of genetic variation at many biological scales. Here we present a strategy for genotype-phenotype reasoning based on existing knowledge of cellular subsystems. These subsystems and their hierarchical organization are defined by the Gene Ontology or a complementary ontology inferred directly from previously published datasets. Guided by the ontology's hierarchical structure, we organize genotype data into an "ontotype," that is, a hierarchy of perturbations representing the effects of genetic variation at multiple cellular scales. The ontotype is then interpreted using logical rules generated by machine learning to predict phenotype. This approach substantially outperforms previous, non-hierarchical methods for translating yeast genotype to cell growth phenotype, and it accurately predicts the growth outcomes of two new screens of 2,503 double gene knockouts impacting DNA repair or nuclear lumen. Ontotypes also generalize to larger knockout combinations, setting the stage for interpreting the complex genetics of disease.

Whole genome sequencing of Saccharomyces cerevisiae: from genotype to phenotype for improved metabolic engineering applications.

PubMed

Otero, José Manuel; Vongsangnak, Wanwipa; Asadollahi, Mohammad A; Olivares-Hernandes, Roberto; Maury, Jérôme; Farinelli, Laurent; Barlocher, Loïc; Osterås, Magne; Schalk, Michel; Clark, Anthony; Nielsen, Jens

2010-12-22

The need for rapid and efficient microbial cell factory design and construction are possible through the enabling technology, metabolic engineering, which is now being facilitated by systems biology approaches. Metabolic engineering is often complimented by directed evolution, where selective pressure is applied to a partially genetically engineered strain to confer a desirable phenotype. The exact genetic modification or resulting genotype that leads to the improved phenotype is often not identified or understood to enable further metabolic engineering. In this work we performed whole genome high-throughput sequencing and annotation can be used to identify single nucleotide polymorphisms (SNPs) between Saccharomyces cerevisiae strains S288c and CEN.PK113-7D. The yeast strain S288c was the first eukaryote sequenced, serving as the reference genome for the Saccharomyces Genome Database, while CEN.PK113-7D is a preferred laboratory strain for industrial biotechnology research. A total of 13,787 high-quality SNPs were detected between both strains (reference strain: S288c). Considering only metabolic genes (782 of 5,596 annotated genes), a total of 219 metabolism specific SNPs are distributed across 158 metabolic genes, with 85 of the SNPs being nonsynonymous (e.g., encoding amino acid modifications). Amongst metabolic SNPs detected, there was pathway enrichment in the galactose uptake pathway (GAL1, GAL10) and ergosterol biosynthetic pathway (ERG8, ERG9). Physiological characterization confirmed a strong deficiency in galactose uptake and metabolism in S288c compared to CEN.PK113-7D, and similarly, ergosterol content in CEN.PK113-7D was significantly higher in both glucose and galactose supplemented cultivations compared to S288c. Furthermore, DNA microarray profiling of S288c and CEN.PK113-7D in both glucose and galactose batch cultures did not provide a clear hypothesis for major phenotypes observed, suggesting that genotype to phenotype correlations are manifested post-transcriptionally or post-translationally either through protein concentration and/or function. With an intensifying need for microbial cell factories that produce a wide array of target compounds, whole genome high-throughput sequencing and annotation for SNP detection can aid in better reducing and defining the metabolic landscape. This work demonstrates direct correlations between genotype and phenotype that provides clear and high-probability of success metabolic engineering targets. The genome sequence, annotation, and a SNP viewer of CEN.PK113-7D are deposited at http://www.sysbio.se/cenpk.

Whole genome sequencing of Saccharomyces cerevisiae: from genotype to phenotype for improved metabolic engineering applications

PubMed Central

2010-01-01

Background The need for rapid and efficient microbial cell factory design and construction are possible through the enabling technology, metabolic engineering, which is now being facilitated by systems biology approaches. Metabolic engineering is often complimented by directed evolution, where selective pressure is applied to a partially genetically engineered strain to confer a desirable phenotype. The exact genetic modification or resulting genotype that leads to the improved phenotype is often not identified or understood to enable further metabolic engineering. Results In this work we performed whole genome high-throughput sequencing and annotation can be used to identify single nucleotide polymorphisms (SNPs) between Saccharomyces cerevisiae strains S288c and CEN.PK113-7D. The yeast strain S288c was the first eukaryote sequenced, serving as the reference genome for the Saccharomyces Genome Database, while CEN.PK113-7D is a preferred laboratory strain for industrial biotechnology research. A total of 13,787 high-quality SNPs were detected between both strains (reference strain: S288c). Considering only metabolic genes (782 of 5,596 annotated genes), a total of 219 metabolism specific SNPs are distributed across 158 metabolic genes, with 85 of the SNPs being nonsynonymous (e.g., encoding amino acid modifications). Amongst metabolic SNPs detected, there was pathway enrichment in the galactose uptake pathway (GAL1, GAL10) and ergosterol biosynthetic pathway (ERG8, ERG9). Physiological characterization confirmed a strong deficiency in galactose uptake and metabolism in S288c compared to CEN.PK113-7D, and similarly, ergosterol content in CEN.PK113-7D was significantly higher in both glucose and galactose supplemented cultivations compared to S288c. Furthermore, DNA microarray profiling of S288c and CEN.PK113-7D in both glucose and galactose batch cultures did not provide a clear hypothesis for major phenotypes observed, suggesting that genotype to phenotype correlations are manifested post-transcriptionally or post-translationally either through protein concentration and/or function. Conclusions With an intensifying need for microbial cell factories that produce a wide array of target compounds, whole genome high-throughput sequencing and annotation for SNP detection can aid in better reducing and defining the metabolic landscape. This work demonstrates direct correlations between genotype and phenotype that provides clear and high-probability of success metabolic engineering targets. The genome sequence, annotation, and a SNP viewer of CEN.PK113-7D are deposited at http://www.sysbio.se/cenpk. PMID:21176163

Study design and rationale for Optimal aNtiplatelet pharmacotherapy guided by bedSIDE genetic or functional TESTing in elective percutaneous coronary intervention patients (ONSIDE TEST): a prospective, open-label, randomised parallel-group multicentre trial (NCT01930773).

PubMed

Kołtowski, Łukasz; Aradi, Daniel; Huczek, Zenon; Tomaniak, Mariusz; Sibbing, Dirk; Filipiak, Krzysztof J; Kochman, Janusz; Balsam, Paweł; Opolski, Grzegorz

2016-01-01

High platelet reactivity (HPR) and presence of CYP2C19 loss-of-function alleles are associated with higher risk for periprocedural myocardial infarction in clopidogrel-treated patients undergoing percutaneous coronary intervention (PCI). It is unknown whether personalised treatment based on platelet function testing or genotyping can prevent such complications. The ONSIDE-TEST is a multicentre, prospective, open-label, randomised controlled clinical trial aiming to assess if optimisation of antiplatelet therapy based on either phenotyping or genotyping is superior to conventional care. Patients will be randomised into phenotyping, genotyping, or control arms. In the phenotyping group, patients will be tested with the VerifyNow P2Y12 assay before PCI, and patients with a platelet reactivity unit greater than 208 will be switched over to prasugrel, while others will continue on clopidogrel therapy. In the genotyping group, carriers of the *2 loss-of-function allele will receive prasugrel for PCI, while wild-type subjects will be treated with clopidogrel. Patients in the control arm will be treated with standard-dose clopidogrel. The primary endpoint of the study is the prevalence of periprocedural myocardial injury within 24 h after PCI in the controls as compared to the phenotyping and genotyping group. Secondary endpoints include cardiac death, myocardial infarction, definite or probable stent thrombosis, or urgent repeat revascularisation within 30 days of PCI. Primary safety outcome is Bleeding Academic Research Consortium (BARC) type 3 and 5 bleeding during 30 days of PCI. The ONSIDE TEST trial is expected to verify the clinical utility of an individualised antiplatelet strategy in preventing periprocedural myocardial injury by either phenotyping or genotyping. ClinicalTrials.gov: NCT01930773.

Modification of Multiple Sclerosis Phenotypes by African Ancestry at HLA

PubMed Central

Cree, Bruce A. C.; Reich, David E.; Khan, Omar; De Jager, Philip L.; Nakashima, Ichiro; Takahashi, Toshiyuki; Bar-Or, Amit; Tong, Christine; Hauser, Stephen L.; Oksenberg, Jorge R.

2015-01-01

Background In those with multiple sclerosis (MS), African American individuals have a more severe disease course, an older age at onset, and more often have clinical manifestations restricted to the optic nerves and spinal cord (opticospinal MS) than white persons. Objective To determine whether genetic variation influences clinical MS patterns. Design Retrospective multicenter cohort study. Participants Six hundred seventy-three African American and 717 white patients with MS. Main Outcome Measures Patients with MS were geno-typed for HLA-DRB1 and HLA-DQB1 alleles. The proportion of European ancestry at HLA was estimated by genotyping single-nucleotide polymorphisms with known significant frequency differences in West African and European populations. These genotypes were correlated with the opticospinal disease phenotype, disability measures, and age at onset. Results Subjects with DRB1*15 alleles were twice as likely to have typical MS rather than opticospinal MS (P = .001). Of the subjects with opticospinal MS or a history of recurrent transverse myelitis who were seropositive for anti–aquaporin 4 antibodies (approximately 5%), none carried DRB1*15 alleles (P = .008). Independently of DRB1* 15, African ancestry at HLA correlated with disability as measured by the Multiple Sclerosis Severity Score (P < .001) andriskof cane dependency (hazard ratio, 1.36; P < .001); DRB1*15 alleles were associated with a 2.1-year earlier age at onset (P < .001). Conclusions These data indicate that the role of HLA in MS is not limited to disease susceptibility but that genes embedded in this locus also influence clinical outcomes. PMID:19204159

Survival by genotype: patterns at Mc1r are not black and white at the White Sands ecotone.

PubMed

Des Roches, S; Sollmann, R; Calhoun, K; Rothstein, A P; Rosenblum, E B

2017-01-01

Measuring links among genotype, phenotype and survival in the wild has long been a focus of studies of adaptation. We conducted a 4-year capture-recapture study to measure survival by genotype and phenotype in the Southwestern Fence Lizard (Sceloporus cowlesi) at the White Sands ecotone (transition area between white sands and dark soil habitats). We report several unanticipated findings. First, in contrast with previous work showing that cryptic blanched coloration in S. cowlesi from the heart of the dunes is associated with mutations in the melanocortin-1 receptor gene (Mc1r), ecotonal S. cowlesi showed minimal association between colour phenotype and Mc1r genotype. Second, the frequency of the derived Mc1r allele in ecotonal S. cowlesi appeared to decrease over time. Third, our capture-recapture data revealed a lower survival rate for S. cowlesi individuals with the derived Mc1r allele. Thus, our results suggest that selection at the ecotone may have favoured the wild-type allele in recent years. Even in a system where a genotype-phenotype association appeared to be black and white, our study suggests that additional factors - including phenotypic plasticity, epistasis, pleiotropy and gene flow - may play important roles at the White Sands ecotone. Our study highlights the importance of linking molecular, genomic and organismal approaches for understanding adaptation in the wild. Furthermore, our findings indicate that dynamics of natural selection can be particularly complex in transitional habitats like ecotones and emphasize the need for future research that examines the patterns of ongoing selection in other ecological 'grey' zones. © 2016 John Wiley & Sons Ltd.

The First Molecular Phylogeny of Strepsiptera (Insecta) Reveals an Early Burst of Molecular Evolution Correlated with the Transition to Endoparasitism

PubMed Central

McMahon, Dino P.; Hayward, Alexander; Kathirithamby, Jeyaraney

2011-01-01

A comprehensive model of evolution requires an understanding of the relationship between selection at the molecular and phenotypic level. We investigate this in Strepsiptera, an order of endoparasitic insects whose evolutionary biology is poorly studied. We present the first molecular phylogeny of Strepsiptera, and use this as a framework to investigate the association between parasitism and molecular evolution. We find evidence of a significant burst in the rate of molecular evolution in the early history of Strepsiptera. The evolution of morphological traits linked to parasitism is significantly correlated with the pattern in molecular rate. The correlated burst in genotypic-phenotypic evolution precedes the main phase of strepsipteran diversification, which is characterised by the return to a low and even molecular rate, and a period of relative morphological stability. These findings suggest that the transition to endoparasitism led to relaxation of selective constraint in the strepsipteran genome. Our results indicate that a parasitic lifestyle can affect the rate of molecular evolution, although other causal life-history traits correlated with parasitism may also play an important role. PMID:21738621

The Genotype and Phenotype (GaP) registry: a living biobank for the analysis of quantitative traits.

PubMed

Gregersen, Peter K; Klein, Gila; Keogh, Mary; Kern, Marlena; DeFranco, Margaret; Simpfendorfer, Kim R; Kim, Sun Jung; Diamond, Betty

2015-12-01

We describe the development of the Genotype and Phenotype (GaP) Registry, a living biobank of normal volunteers who are genotyped for genetic markers related to human disease. Participants in the GaP can be recalled for hypothesis driven study of disease associated genetic variants. The GaP has facilitated functional studies of several autoimmune disease associated loci including Csk, Blk, PDRM1 (Blimp-1) and PTPN22. It is likely that expansion of such living biobank registries will play an important role in studying and understanding the function of disease associated alleles in complex disease.

Congenital stationary night blindness: an analysis and update of genotype-phenotype correlations and pathogenic mechanisms.

PubMed

Zeitz, Christina; Robson, Anthony G; Audo, Isabelle

2015-03-01

Congenital stationary night blindness (CSNB) refers to a group of genetically and clinically heterogeneous retinal disorders. Seventeen different genes with more than 360 different mutations and more than 670 affected alleles have been associated with CSNB, including genes coding for proteins of the phototransduction cascade, those important for signal transmission from the photoreceptors to the bipolar cells or genes involved in retinoid recycling in the retinal pigment epithelium. This article describes the phenotypic characteristics of different forms of CSNB that are necessary for accurate diagnosis and to direct and improve genetic testing. An overview of classical and recent methods used to identify specific CSNB genotypes is provided and a meta-analysis of all previously published and novel data is performed to determine the prevalence of disease-causing mutations. Studies of the underlying molecular pathogenic mechanisms based on cell culture techniques and animal studies are outlined. The article highlights how the study of CSNB has increased understanding of the mechanisms of visual signalling in the retina, likely to prove important in developing future treatments for CSNB and other retinal disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gene expression regulation by upstream open reading frames and human disease.

PubMed

Barbosa, Cristina; Peixeiro, Isabel; Romão, Luísa

2013-01-01

Upstream open reading frames (uORFs) are major gene expression regulatory elements. In many eukaryotic mRNAs, one or more uORFs precede the initiation codon of the main coding region. Indeed, several studies have revealed that almost half of human transcripts present uORFs. Very interesting examples have shown that these uORFs can impact gene expression of the downstream main ORF by triggering mRNA decay or by regulating translation. Also, evidence from recent genetic and bioinformatic studies implicates disturbed uORF-mediated translational control in the etiology of many human diseases, including malignancies, metabolic or neurologic disorders, and inherited syndromes. In this review, we will briefly present the mechanisms through which uORFs regulate gene expression and how they can impact on the organism's response to different cell stress conditions. Then, we will emphasize the importance of these structures by illustrating, with specific examples, how disturbed uORF-mediated translational control can be involved in the etiology of human diseases, giving special importance to genotype-phenotype correlations. Identifying and studying more cases of uORF-altering mutations will help us to understand and establish genotype-phenotype associations, leading to advancements in diagnosis, prognosis, and treatment of many human disorders.

Systemic vascular phenotypes of Loeys-Dietz syndrome in a child carrying a de novo R381P mutation in TGFBR2: a case report.

PubMed

Uike, Kiyoshi; Matsushita, Yuki; Sakai, Yasunari; Togao, Osamu; Nagao, Michinobu; Ishizaki, Yoshito; Nagata, Hazumu; Yamamura, Kenichiro; Torisu, Hiroyuki; Hara, Toshiro

2013-11-12

Loeys-Dietz syndrome, also known as Marfan syndrome type II, is a rare connective tissue disorder caused by dominant mutations in transforming growth factor-beta receptors (TGFBR1 and 2). We report a 7-year-old Japanese boy with Loeys-Dietz syndrome who carried a novel, de novo missense mutation in TGFBR2 (c.1142g > c, R381P). He showed dysmorphic faces and skeletal malformations that were typical in previous cases with Loeys-Dietz syndrome. The cardiac studies disclosed the presence of markedly dilated aortic root and patent ductus aorteriosus. The cranial magnetic resonance imaging (MRI) and angiography (MRA) detected the tortuous appearances of the bilateral middle cerebral and carotid arteries. This study depicts the systemic vascular phenotypes of a child with Loeys-Dietz syndrome that were caused by a novel heterozygous mutation of TGFR2. A large cohort with serial imaging studies for vascular phenotypes will be useful for delineating the genotype-phenotype correlations of Loeys-Dietz syndrome.

Novel SOX2 mutations and genotype-phenotype correlation in anophthalmia and microphthalmia.

PubMed

Schneider, Adele; Bardakjian, Tanya; Reis, Linda M; Tyler, Rebecca C; Semina, Elena V

2009-12-01

SOX2 represents a High Mobility Group domain containing transcription factor that is essential for normal development in vertebrates. Mutations in SOX2 are known to result in a spectrum of severe ocular phenotypes in humans, also typically associated with other systemic defects. Ocular phenotypes include anophthalmia/microphthalmia (A/M), optic nerve hypoplasia, ocular coloboma and other eye anomalies. We screened 51 unrelated individuals with A/M and identified SOX2 mutations in the coding region of the gene in 10 individuals. Seven of the identified mutations are novel alterations, while the remaining three individuals carry the previously reported recurrent 20-nucleotide deletion in SOX2, c.70del20. Among the SOX2-positive cases, seven patients had bilateral A/M and mutations resulting in premature termination of the normal protein sequence (7/38; 18% of all bilateral cases), one patient had bilateral A/M associated with a single amino acid insertion (1/38; 3% of bilateral cases), and the final two patients demonstrated unilateral A/M associated with missense mutations (2/13; 15% of all unilateral cases). These findings and review of previously reported cases suggest a potential genotype/phenotype correlation for SOX2 mutations with missense changes generally leading to less severe ocular defects. In addition, we report a new familial case of affected siblings with maternal mosaicism for the identified SOX2 mutation, which further underscores the importance of parental testing to provide accurate genetic counseling to families.

Novel SOX2 Mutations and Genotype-Phenotype Correlation in Anophthalmia and Microphthalmia

PubMed Central

Schneider, Adele; Bardakjian, Tanya; Reis, Linda M.; Tyler, Rebecca C.; Semina, Elena V.

2009-01-01

SOX2 represents a High Mobility Group domain containing transcription factor that is essential for normal development in vertebrates. Mutations in SOX2 are known to result in a spectrum of severe ocular phenotypes in humans, also typically associated with other systemic defects. Ocular phenotypes include anophthalmia/microphthalmia (A/M), optic nerve hypoplasia, ocular coloboma and other eye anomalies. We screened 51 unrelated individuals with A/M and indentified SOX2 mutations in the coding region of the gene in 10 individuals. Seven of the identified mutations are novel alterations, while the remaining three individuals carry the previously reported recurrent 20-nucleotide deletion in SOX2, c.70del20. Among the SOX2-positive cases, seven patients had bilateral A/M and mutations resulting in premature termination of the normal protein sequence (7/38; 18% of all bilateral cases), one patient had bilateral A/M associated with a single amino acid insertion (1/38; 3% of bilateral cases), and the final two patients demonstrated unilateral A/M associated with missense mutations (2/13; 15% of all unilateral cases). These findings and review of previously reported cases suggest a potential genotype/phenotype correlation for SOX2 mutations with missense changes generally leading to less severe ocular defects. In addition, we report a new familial case of affected siblings with maternal mosaicism for the identified SOX2 mutation, which further underscores the importance of parental testing to provide accurate genetic counseling to families. PMID:19921648

Accuracy of various human NAT2 SNP genotyping panels to infer rapid, intermediate and slow acetylator phenotypes

PubMed Central

Hein, David W; Doll, Mark A

2012-01-01

Aim Humans exhibit genetic polymorphism in NAT2 resulting in rapid, intermediate and slow acetylator phenotypes. Over 65 NAT2 variants possessing one or more SNPs in the 870-bp NAT2 coding region have been reported. The seven most frequent SNPs are rs1801279 (191G>A), rs1041983 (282C>T), rs1801280 (341T>C), rs1799929 (481C>T), rs1799930 (590G>A), rs1208 (803A>G) and rs1799931 (857G>A). The majority of studies investigate the NAT2 genotype assay for three SNPs: 481C>T, 590G>A and 857G>A. A tag-SNP (rs1495741) recently identified in a genome-wide association study has also been proposed as a biomarker for the NAT2 phenotype. Materials & methods Sulfamethazine N-acetyltransferase catalytic activities were measured in cryopreserved human hepatocytes from a convenience sample of individuals in the USA with an ethnic frequency similar to the 2010 US population census. These activities were segregated by the tag-SNP rs1495741 and each of the seven SNPs described above. We assessed the accuracy of the tag-SNP and various two-, three-, four- and seven-SNP genotyping panels for their ability to accurately infer NAT2 phenotype. Results The accuracy of the various NAT2 SNP genotype panels to infer NAT2 phenotype were as follows: seven-SNP: 98.4%; tag-SNP: 77.7%; two-SNP: 96.1%; three-SNP: 92.2%; and four-SNP: 98.4%. Conclusion A NAT2 four-SNP genotype panel of rs1801279 (191G>A), rs1801280 (341T>C), rs1799930 (590G>A) and rs1799931 (857G>A) infers NAT2 acetylator phenotype with high accuracy, and is recommended over the tag-, two-, three- and (for economy of scale) the seven-SNP genotyping panels, particularly in populations of non-European ancestry. PMID:22092036

Endocrine profile and phenotype-(epi)genotype correlation in Spanish patients with pseudohypoparathyroidism.

PubMed

Fernández-Rebollo, Eduardo; Lecumberri, Beatriz; Gaztambide, Sonia; Martinez-Indart, Lorea; Perez de Nanclares, Guiomar; Castaño, Luis

2013-05-01

Recent advances in genetics and epigenetics have revealed an overlap between molecular and clinical features of pseudohypoparathyroidism (PHP) subtypes, broadening the previous spectrum of PHP genotype-phenotype correlations and indicating limitations of the current classification of the disease. The aim of the study was to screen patients with clinical diagnoses of PHP type I or pseudo-PHP for underlying molecular defects and explore possible correlations between molecular findings and clinical features. We investigated the GNAS locus at the molecular level in 72 affected patients (46 women and 26 men) from 56 nonrelated families. Clinical data were obtained for 63 of these patients (38 women and 25 men). The molecular analysis showed that 35 patients carried structural mutations, 32 had loss of methylation, and 2 had a 2q37 deletion but did not reveal any (epi)mutation for 3 patients. Comparing these results and the clinical data, we observed that a younger age at diagnosis was associated with structural defects at the GNAS gene and epigenetic defects with a diagnosis later in life (9.19 ± 1.64 vs 24.57 ± 2.28 years, P < .0001). This first global review of PHP in Spain highlights the importance of a detailed clinical and genetic study of each patient and the integrated analysis of the findings from the two approaches. It may also help geneticists and clinicians to raise the suspicion of PHP earlier, reach more accurate diagnoses, and provide patients with PHP and their families with useful genetic information and counseling, thereby improving outcomes and quality of life.

Genetic diversity studies and identification of SSR markers associated with Fusarium wilt (Fusarium udum) resistance in cultivated pigeonpea (Cajanus cajan).

PubMed

Singh, A K; Rai, V P; Chand, R; Singh, R P; Singh, M N

2013-01-01

Genetic diversity and identification of simple sequence repeat markers correlated with Fusarium wilt resistance was performed in a set of 36 elite cultivated pigeonpea genotypes differing in levels of resistance to Fusarium wilt. Twenty-four polymorphic sequence repeat markers were screened across these genotypes, and amplified a total of 59 alleles with an average high polymorphic information content value of 0.52. Cluster analysis, done by UPGMA and PCA, grouped the 36 pigeonpea genotypes into two main clusters according to their Fusarium wilt reaction. Based on the Kruskal-Wallis ANOVA and simple regression analysis, six simple sequence repeat markers were found to be significantly associated with Fusarium wilt resistance. The phenotypic variation explained by these markers ranged from 23.7 to 56.4%. The present study helps in finding out feasibility of prescreened SSR markers to be used in genetic diversity analysis and their potential association with disease resistance.

Non-parallel divergence across freshwater and marine three-spined stickleback Gasterosteus aculeatus populations.

PubMed

Pujolar, J M; Ferchaud, A L; Bekkevold, D; Hansen, M M

2017-07-01

This work investigated whether multiple freshwater populations of three-spined stickleback Gasterosteus aculeatus in different freshwater catchments in the Jutland Peninsula, Denmark, derived from the same marine populations show repeated adaptive responses. A total of 327 G. aculeatus collected at 13 sampling locations were screened for genetic variation using a combination of 70 genes putatively under selection and 26 neutral genes along with a marker linked to the ectodysplasin gene (eda), which is strongly correlated with plate armour morphs in the species. A highly significant genetic differentiation was found that was higher among different freshwater samples than between marine-freshwater samples. Tests for selection between marine and freshwater populations showed a very low degree of parallelism and no single nucleotide polymorphism was detected as outlier in all freshwater-marine pairwise comparisons, including the eda. This suggests that G. aculeatus is not necessarily the prime example of parallel local adaptation suggested in much of the literature and that important exceptions exist (i.e. the Jutland Peninsula). While marine populations in the results described here showed a high phenotype-genotype correlation at eda, a low association was found for most of the freshwater populations. The most extreme case was found in the freshwater Lake Hald where all low-plated phenotypes were either homozygotes for the allele supposed to be associated with completely plated morphs or heterozygotes, but none were homozygotes for the putative low-plated allele. Re-examination of data from seven G. aculeatus studies agrees in showing a high but partial association between phenotype-genotype at eda in G. aculeatus freshwater populations and that mismatches occur everywhere in the European regions studied (higher in some areas, i.e. Denmark). This is independent of the eda marker used. © 2017 The Fisheries Society of the British Isles.

Unisexual and Heterosexual Meiotic Reproduction Generate Aneuploidy and Phenotypic Diversity De Novo in the Yeast Cryptococcus neoformans

PubMed Central

Li, Wenjun; Floyd-Averette, Anna; Mieczkowski, Piotr; Dietrich, Fred S.; Heitman, Joseph

2013-01-01

Aneuploidy is known to be deleterious and underlies several common human diseases, including cancer and genetic disorders such as trisomy 21 in Down's syndrome. In contrast, aneuploidy can also be advantageous and in fungi confers antifungal drug resistance and enables rapid adaptive evolution. We report here that sexual reproduction generates phenotypic and genotypic diversity in the human pathogenic yeast Cryptococcus neoformans, which is globally distributed and commonly infects individuals with compromised immunity, such as HIV/AIDS patients, causing life-threatening meningoencephalitis. C. neoformans has a defined a-α opposite sexual cycle; however, >99% of isolates are of the α mating type. Interestingly, α cells can undergo α-α unisexual reproduction, even involving genotypically identical cells. A central question is: Why would cells mate with themselves given that sex is costly and typically serves to admix preexisting genetic diversity from genetically divergent parents? In this study, we demonstrate that α-α unisexual reproduction frequently generates phenotypic diversity, and the majority of these variant progeny are aneuploid. Aneuploidy is responsible for the observed phenotypic changes, as chromosome loss restoring euploidy results in a wild-type phenotype. Other genetic changes, including diploidization, chromosome length polymorphisms, SNPs, and indels, were also generated. Phenotypic/genotypic changes were not observed following asexual mitotic reproduction. Aneuploidy was also detected in progeny from a-α opposite-sex congenic mating; thus, both homothallic and heterothallic sexual reproduction can generate phenotypic diversity de novo. Our study suggests that the ability to undergo unisexual reproduction may be an evolutionary strategy for eukaryotic microbial pathogens, enabling de novo genotypic and phenotypic plasticity and facilitating rapid adaptation to novel environments. PMID:24058295

Paternally inherited microdeletion at 15q11.2 confirms a significant role for the SNORD116 C/D box snoRNA cluster in Prader-Willi syndrome.

PubMed

Duker, Angela L; Ballif, Blake C; Bawle, Erawati V; Person, Richard E; Mahadevan, Sangeetha; Alliman, Sarah; Thompson, Regina; Traylor, Ryan; Bejjani, Bassem A; Shaffer, Lisa G; Rosenfeld, Jill A; Lamb, Allen N; Sahoo, Trilochan

2010-11-01

Prader-Willi syndrome (PWS) is a neurobehavioral disorder manifested by infantile hypotonia and feeding difficulties in infancy, followed by morbid obesity secondary to hyperphagia. It is caused by deficiency of paternally expressed transcript(s) within the human chromosome region 15q11.2. PWS patients harboring balanced chromosomal translocations with breakpoints within small nuclear ribonucleoprotein polypeptide N (SNRPN) have provided indirect evidence for a role for the imprinted C/D box containing small nucleolar RNA (snoRNA) genes encoded downstream of SNRPN. In addition, recently published data provide strong evidence in support of a role for the snoRNA SNORD116 cluster (HBII-85) in PWS etiology. In this study, we performed detailed phenotypic, cytogenetic, and molecular analyses including chromosome analysis, array comparative genomic hybridization (array CGH), expression studies, and single-nucleotide polymorphism (SNP) genotyping for parent-of-origin determination of the 15q11.2 microdeletion on an 11-year-old child expressing the major components of the PWS phenotype. This child had an ∼236.29 kb microdeletion at 15q11.2 within the larger Prader-Willi/Angelman syndrome critical region that included the SNORD116 cluster of snoRNAs. Analysis of SNP genotypes in proband and mother provided evidence in support of the deletion being on the paternal chromosome 15. This child also met most of the major PWS diagnostic criteria including infantile hypotonia, early-onset morbid obesity, and hypogonadism. Identification and characterization of this case provide unequivocal evidence for a critical role for the SNORD116 snoRNA molecules in PWS pathogenesis. Array CGH testing for genomic copy-number changes in cases with complex phenotypes is proving to be invaluable in detecting novel alterations and enabling better genotype-phenotype correlations.

The differential view of genotype–phenotype relationships

PubMed Central

Orgogozo, Virginie; Morizot, Baptiste; Martin, Arnaud

2015-01-01

An integrative view of diversity and singularity in the living world requires a better understanding of the intricate link between genotypes and phenotypes. Here we re-emphasize the old standpoint that the genotype–phenotype (GP) relationship is best viewed as a connection between two differences, one at the genetic level and one at the phenotypic level. As of today, predominant thinking in biology research is that multiple genes interact with multiple environmental variables (such as abiotic factors, culture, or symbionts) to produce the phenotype. Often, the problem of linking genotypes and phenotypes is framed in terms of genotype and phenotype maps, and such graphical representations implicitly bring us away from the differential view of GP relationships. Here we show that the differential view of GP relationships is a useful explanatory framework in the context of pervasive pleiotropy, epistasis, and environmental effects. In such cases, it is relevant to view GP relationships as differences embedded into differences. Thinking in terms of differences clarifies the comparison between environmental and genetic effects on phenotypes and helps to further understand the connection between genotypes and phenotypes. PMID:26042146

CYP2D6 genotype and phenotype in Amerindians of Tepehuano origin and Mestizos of Durango, Mexico.

PubMed

Sosa-Macías, Martha; Elizondo, Guillermo; Flores-Pérez, Carmen; Flores-Pérez, Janet; Bradley-Alvarez, Francisco; Alanis-Bañuelos, Ruth E; Lares-Asseff, Ismael

2006-05-01

Although the drug-metabolizing enzyme CYP2D6 has been studied extensively in subjects of differing ethnicities, limited CYP2D6 pharmacogenetic data are available for the Amerindian population and Mestizos of Mexico. Dextromethorphan hydroxylation phenotype was studied in Tepehuano Amerindian (n = 58) and Mestizo (n = 88) subjects, and 195 individuals (85 Tepehuano Amerindians and 110 Mestizos) were genotyped by polymerase chain reaction-restriction fragment length polymorphism methods to identify the frequencies of the CYP2D6*3, *4, *6, and *10 alleles. Tepehuano Amerindian subjects lacked the poor metabolizer (PM) phenotype, whereas in Mestizos the PM phenotype frequency was 6.8%. The CYP2D6*3, *6, and *10 alleles were not found in Tepehuano Amerindians. The CYP2D6*4 allele had a low frequency (0.006) in this Amerindian group. In the Mestizo group, the CYP2D6*3, *4, and *10 alleles had frequencies of 0.009, 0.131, and 0.023, respectively. The CYP2D6*6 allele was not found in Mestizos. The genotype-phenotype association was strongly statistically significant (r(2) = .45; P = .005) in Mestizos. The Tepehuano population was found to have a low phenotypic and genotypic CYP2D6 diversity and differed from other Amerindian groups. On the other hand, the frequencies of the CYP2D6 variant alleles in Mestizos were similar to those reported for whites.

Identification of novel mutations of the WFS1 gene in Brazilian patients with Wolfram syndrome.

PubMed

Gasparin, Maria Regina R; Crispim, Felipe; Paula, Sílvia L; Freire, Maria Beatriz S; Dalbosco, Ivaldir S; Manna, Thais Della; Salles, João Eduardo N; Gasparin, Fábio; Guedes, Aléxis; Marcantonio, João M; Gambini, Márcio; Salim, Camila P; Moisés, Regina S

2009-02-01

Wolfram syndrome (WS) is a rare, progressive, neurodegenerative disorder with an autosomal recessive pattern of inheritance. The gene for WS, WFS1, was identified on chromosome 4p16 and most WS patients carry mutations in this gene. However, some studies have provided evidence for genetic heterogeneity and the genotype-phenotype relationships are not clear. Our aim was to ascertain the spectrum of WFS1 mutations in Brazilian patients with WS and to examine the phenotype-genotype relationships in these patients. Clinical characterization and analyses of the WFS1 gene were performed in 27 Brazilian patients with WS from 19 families. We identified 15 different mutations in the WFS1 gene in 26 patients, among which nine are novel. All mutations occurred in exon 8, except for one missense mutation which was located in exon 5. Although we did not find any clear phenotype-genotype relationship in patients with mutations in exon 8, the homozygous missense mutation in exon 5 was associated with a mild phenotype: onset of diabetes mellitus and optic atrophy during adulthood with good metabolic control being achieved with low doses of sulfonylurea. Our data show that WFS1 is the major gene involved in WS in Brazilian patients and most mutations are concentrated in exon 8. Also, our study increases the spectrum of WFS1 mutations. Although no clear phenotype-genotype relationship was found for mutations in exon 8, a mild phenotype was associated with a homozygous missense mutation in exon 5.

Morphophysiology, Phenotypic and Molecular Diversity of Auxin-induced Passiflora mucronata Lam. (Passifloraceae).

PubMed

França, Juliany M; Venial, Lucimara R; Costa, Eloá B; Schmildt, Edilson R; Schmildt, Omar; Bernardes, Paula M; Tatagiba, Sandro D; Lopes, José C; Ferreira, Marcia F S; Alexandre, Rodrigo S

2018-01-01

Genetic diversity allows identification of potential intraspecific genotypes in the genus Passiflora. The objective of this study was to examine the morphological and genetic diversity of auxin-induced Passiflora mucronata. The experiments were arranged in a complete randomized block design, with a 9 x 2 factorial arrangement (nine genotypes x presence and absence of auxin, indole-3-butyric acid (IBA)), with four replicates of 16 cuttings. The rooting and vegetative growth responses were variable. Genotype 5 was more responsive in the absence of IBA and genotypes 3, 8 and 9 were more responsive in the presence of IBA. Auxin increased rooting rate and percentage, reducing the average time of root protrusion in eight days. IBA also contributed to increase photosynthesis and dry root and shoot mass in 55.55 and 44.44% of the genotypes, respectively. The highest relative contribution to phenotypic diversity in the absence of auxin was rate (38.75%) and percentage (20.27%) of rooting, whereas in the presence of auxin was stomatal conductance (23.19%) and root dry mass (20.91%). Similarity was found for phenotypic and molecular divergence in the presence of IBA, in which genotypes 1 and 6; genotypes 5, 8 and 9; and genotype 3 were clustered in distinct groups.

Genetic diagnosis of X-linked dominant hypophosphatemic rickets in a cohort study: Tubular reabsorption of phosphate and 1,25(OH)2D serum levels are associated with PHEX mutation type

PubMed Central

2011-01-01

Background Genetic Hypophosphatemic Rickets (HR) is a group of diseases characterized by renal phosphate wasting with inappropriately low or normal 1,25-dihydroxyvitamin D3 (1,25(OH)2D) serum levels. The most common form of HR is X-linked dominant HR (XLHR) which is caused by inactivating mutations in the PHEX gene. The purpose of this study was to perform genetic diagnosis in a cohort of patients with clinical diagnosis of HR, to perform genotype-phenotype correlations of those patients and to compare our data with other HR cohort studies. Methods Forty three affected individuals from 36 non related families were analyzed. For the genetic analysis, the PHEX gene was sequenced in all of the patients and in 13 cases the study was complemented by mRNA sequencing and Multiple Ligation Probe Assay. For the genotype-phenotype correlation study, the clinical and biochemical phenotype of the patients was compared with the type of mutation, which was grouped into clearly deleterious or likely causative, using the Mann-Whitney and Fisher's exact test. Results Mutations in the PHEX gene were identified in all the patients thus confirming an XLHR. Thirty four different mutations were found distributed throughout the gene with higher density at the 3' end. The majority of the mutations were novel (69.4%), most of them resulted in a truncated PHEX protein (83.3%) and were family specific (88.9%). Tubular reabsorption of phosphate (TRP) and 1,25(OH)2D serum levels were significantly lower in patients carrying clearly deleterious mutations than in patients carrying likely causative ones (61.39 ± 19.76 vs. 80.14 ± 8.80%, p = 0.028 and 40.93 ± 30.73 vs. 78.46 ± 36.27 pg/ml, p = 0.013). Conclusions PHEX gene mutations were found in all the HR cases analyzed, which was in contrast with other cohort studies. Patients with clearly deleterious PHEX mutations had lower TRP and 1,25(OH)2D levels suggesting that the PHEX type of mutation might predict the XLHR phenotype severity. PMID:21902834

Genotype by environment interactions for growth in Red Angus.

PubMed

Fennewald, D J; Weaber, R L; Lamberson, W R

2017-02-01

Accuracy of sire selection is limited by how well animals are characterized for their environment. The objective of this study was to evaluate the presence of genotype × environment interactions (G×E) for birth weight (BiW) and weaning weight (WW) for Red Angus in the United States. Adjusted weights were provided by the Red Angus Association of America. Environments were defined as 9 regions within the continental United States with similar temperature-humidity indices. Mean weights of calves were determined for each region and for each sire's progeny within each region. A reaction norm (RN) for each bull was estimated by regressing the sire means on the region means weighted for the number of progeny of each sire. The range for BiW and WW RN was -1.3 to 4.0 and -1.7 to 2.8, respectively. The heritabilities of BiW and WW RN were 0.40 and 0.39, respectively. Phenotypic and genetic correlations between BiW and WW RN were 0.19 and 0.54, respectively. The phenotypic correlation of the progeny mean to the RN was -0.20 ( <0.05) and suggests that sires with higher means are more stable in progeny performance across environments. Weights in different regions were considered separate traits and genetic correlations were estimated between all pairs of regions as another method to determine G×E. Genetic correlations < 0.80 indicate G×E at a level for concern, but existed for only 2 of 36 estimates for BiW and 12 of 36 estimates for WW. Genetic correlations between different regions ranged from 0.74 to 0.96 for BiW and 0.62 to 0.99 for WW and indicate that sires tend to rank similarly across environments for these traits.

Genotyping in 46 patients with tentative diagnosis of Treacher Collins syndrome revealed unexpected phenotypic variation.

PubMed

Teber, Ozge Altug; Gillessen-Kaesbach, Gabriele; Fischer, Sven; Böhringer, Stefan; Albrecht, Beate; Albert, Angelika; Arslan-Kirchner, Mine; Haan, Eric; Hagedorn-Greiwe, Monika; Hammans, Christof; Henn, Wolfram; Hinkel, Georg Klaus; König, Rainer; Kunstmann, Erdmute; Kunze, Jürgen; Neumann, Luitgard M; Prott, Eva-Christina; Rauch, Anita; Rott, Hans-Dieter; Seidel, Heide; Spranger, Stephanie; Sprengel, Martin; Zoll, Barbara; Lohmann, Dietmar R; Wieczorek, Dagmar

2004-11-01

To define the range of phenotypic expression in Treacher Collins syndrome (TCS; Franceschetti-Klein syndrome), we performed mutation analysis in the TCOF1 gene in 46 patients with tentative diagnosis of TCS and evaluated the clinical data, including a scoring system. A total of 27 coding exons of TCOF1 and adjacent splice junctions were analysed by direct sequencing. In 36 patients with a clinically unequivocal diagnosis of TCS, we detected 28 pathogenic mutations, including 25 novel alterations. No mutation was identified in the remaining eight patients with unequivocal diagnosis of TCS and 10 further patients, in whom the referring diagnosis of TCS was clinically doubtful. There is no overt genotype-phenotype correlation except that conductive deafness is significantly less frequent in patients with mutations in the 3' part of the open reading frame. Inter- and intrafamilial variation is wide. Some mutation carriers, parents of typically affected patients, are so mildly affected that the diagnosis might be overlooked clinically. This suggests that modifying factors are important for phenotypic expression. Based on these findings, minimal diagnostic criteria were defined: downward slanting palpebral fissures and hypoplasia of the zygomatic arch. The difficulties in genetic counselling, especially diagnosis of family members with a mild phenotype, are described.

Brain-derived neurotrophic factor Val66Met polymorphism and alcohol-related phenotypes.

PubMed

Nedic, Gordana; Perkovic, Matea Nikolac; Sviglin, Korona Nenadic; Muck-Seler, Dorotea; Borovecki, Fran; Pivac, Nela

2013-01-10

Alcoholism is a chronic psychiatric disorder affecting neural pathways that regulate motivation, stress, reward and arousal. Brain-derived neurotrophic factor (BDNF) regulates mood, response to stress and interacts with neurotransmitters and stress systems involved in reward pathways and addiction. Aim of the study was to evaluate the association between a single nucleotide polymorphism (BDNF Val66Met or rs6265) and alcohol related phenotypes in Caucasian patients. In ethnically homogenous Caucasian subjects of the Croatian origin, the BDNF Val66Met genotype distribution was determined in 549 male and 126 female patients with alcohol dependence and in 655 male and 259 female healthy non-alcoholic control subjects. Based on the structured clinical interview, additional detailed clinical interview, the Brown-Goodwin Scale, the Hamilton Rating Scale for Depression and the Clinical Global Impression scores, alcoholic patients were subdivided into those with or without comorbid depression, aggression, delirium tremens, withdrawal syndrome, early/late onset of alcohol abuse, prior suicidal attempt during lifetime, current suicidal behavior, and severity of alcohol dependence. The results showed no significant association between BDNF Val66Met variants and alcohol dependence and/or any of the alcohol related phenotypes in either Caucasian women, or men, with alcohol dependence. There are few limitations of the study. The overall study sample size was large (N=1589) but not well-powered to detect differences in BDNF Val66Met genotype distribution between studied groups. Healthy control women were older than female alcoholic patients. Only one BDNF polymorphism (rs6265) was studied. In conclusion, these data do not support the view that BDNF Val66Met polymorphism correlates with the specific alcohol related phenotypes in ethnically homogenous medication-free Caucasian subjects with alcohol dependence. Copyright © 2012 Elsevier Inc. All rights reserved.

Phenotypic plasticity of winter wheat heading date and grain yield across the U.S. Great Plains

USDA-ARS?s Scientific Manuscript database

Phenotypic plasticity describes the range of phenotypes produced by a single genotype under varying environmental conditions. We evaluated the extent of phenotypic variation and plasticity in thermal time to heading and grain yield in 299 hard winter wheat (Triticum aestivum L.) genotypes representa...

Systems properties of the Haemophilus influenzae Rd metabolic genotype.

PubMed

Edwards, J S; Palsson, B O

1999-06-18

Haemophilus influenzae Rd was the first free-living organism for which the complete genomic sequence was established. The annotated sequence and known biochemical information was used to define the H. influenzae Rd metabolic genotype. This genotype contains 488 metabolic reactions operating on 343 metabolites. The stoichiometric matrix was used to determine the systems characteristics of the metabolic genotype and to assess the metabolic capabilities of H. influenzae. The need to balance cofactor and biosynthetic precursor production during growth on mixed substrates led to the definition of six different optimal metabolic phenotypes arising from the same metabolic genotype, each with different constraining features. The effects of variations in the metabolic genotype were also studied, and it was shown that the H. influenzae Rd metabolic genotype contains redundant functions under defined conditions. We thus show that the synthesis of in silico metabolic genotypes from annotated genome sequences is possible and that systems analysis methods are available that can be used to analyze and interpret phenotypic behavior of such genotypes.

How the knowledge of genetic "makeup" and cellular data can affect the analysis of repolarization in surface electrocardiogram.

PubMed

Shimizu, Wataru

2010-01-01

This review article sought to describe patterns of repolarization on the surface electrocardiogram in inherited cardiac arrhythmias and to discuss how the knowledge of genetic makeup and cellular data can affect the analysis based on the data derived from the experimental studies using arterially perfused canine ventricular wedge preparations. Molecular genetic studies have established a link between a number of inherited cardiac arrhythmia syndromes and mutations in genes encoding cardiac ion channels or membrane components during the past 2 decades. Twelve forms of congenital long QT syndrome have been so far identified, and genotype-phenotype correlations have been investigated especially in the 3 major genotypes-LQT1, LQT2, and LQT3. Abnormal T waves are reported in the LQT1, LQT2, and LQT3, and the differences in the time course of repolarization of the epicardial, midmyocardial, and endocardial cells give rise to voltage gradients responsible for the manifestation of phenotypic appearance of abnormal T waves. Brugada syndrome is characterized by ST-segment elevation in leads V1 to V3 and an episode of ventricular fibrillation, in which 7 genotypes have been reported. An intrinsically prominent transient outward current (I(to))-mediated action potential notch and a subsequent loss of action potential dome in the epicardium, but not in the endocardium of the right ventricular outflow tract, give rise to a transmural voltage gradient, resulting in ST-segment elevation, and a subsequent phase 2 reentry-induced ventricular fibrillation. In conclusion, transmural electrical heterogeneity of repolarization across the ventricular wall profoundly affects the phenotypic manifestation of repolarization patterns on the surface electrocardiogram in inherited cardiac arrhythmias. Copyright © 2010 Elsevier Inc. All rights reserved.

Genotype-phenotype analysis of recombinant chromosome 4 syndrome: an array-CGH study and literature review

PubMed Central

2013-01-01

Background Recombinant chromosome 4, a rare constitutional rearrangement arising from pericentric inversion, comprises a duplicated segment of 4p13~p15→4pter and a deleted segment of 4q35→4qter. To date, 10 cases of recombinant chromosome 4 have been reported. Result We describe the second case in which array-CGH was used to characterize recombinant chromosome 4 syndrome. The patient was a one-year old boy with consistent clinical features. Conventional cytogenetics and FISH documented a recombinant chromosome 4, derived from a paternal pericentric inversion, leading to partial trisomy 4p and partial monosomy of 4q. Array-CGH, performed to further characterize the rearranged chromosome 4 and delineate the breakpoints, documented a small (4.36 Mb) 4q35.1 terminal deletion and a large (23.81 Mb) 4p15.1 terminal duplication. Genotype-phenotype analysis of 10 previously reported cases and the present case indicated relatively consistent clinical features and breakpoints. This consistency was more evident in our case and another characterized by array-CGH, where both showed the common breakpoints of p15.1 and q35.1. A genotype-phenotype correlation study between rec(4), dup(4p), and del(4q) syndromes revealed that urogenital and cardiac defects are probably due to the deletion of 4q whereas the other clinical features are likely due to 4p duplication. Conclusion Our findings support that the clinical features of patients with rec(4) are relatively consistent and specific to the regions of duplication or deletion. Recombinant chromosome 4 syndrome thus appears to be a discrete entity that can be suspected on the basis of clinical features or specific deleted and duplicated chromosomal regions. PMID:23639048

Genotype-phenotype analysis of recombinant chromosome 4 syndrome: an array-CGH study and literature review.

PubMed

Hemmat, Morteza; Hemmat, Omid; Anguiano, Arturo; Boyar, Fatih Z; El Naggar, Mohammed; Wang, Jia-Chi; Wang, Borris T; Sahoo, Trilochan; Owen, Renius; Haddadin, Mary

2013-05-02

Recombinant chromosome 4, a rare constitutional rearrangement arising from pericentric inversion, comprises a duplicated segment of 4p13~p15→4pter and a deleted segment of 4q35→4qter. To date, 10 cases of recombinant chromosome 4 have been reported. We describe the second case in which array-CGH was used to characterize recombinant chromosome 4 syndrome. The patient was a one-year old boy with consistent clinical features. Conventional cytogenetics and FISH documented a recombinant chromosome 4, derived from a paternal pericentric inversion, leading to partial trisomy 4p and partial monosomy of 4q. Array-CGH, performed to further characterize the rearranged chromosome 4 and delineate the breakpoints, documented a small (4.36 Mb) 4q35.1 terminal deletion and a large (23.81 Mb) 4p15.1 terminal duplication. Genotype-phenotype analysis of 10 previously reported cases and the present case indicated relatively consistent clinical features and breakpoints. This consistency was more evident in our case and another characterized by array-CGH, where both showed the common breakpoints of p15.1 and q35.1. A genotype-phenotype correlation study between rec(4), dup(4p), and del(4q) syndromes revealed that urogenital and cardiac defects are probably due to the deletion of 4q whereas the other clinical features are likely due to 4p duplication. Our findings support that the clinical features of patients with rec(4) are relatively consistent and specific to the regions of duplication or deletion. Recombinant chromosome 4 syndrome thus appears to be a discrete entity that can be suspected on the basis of clinical features or specific deleted and duplicated chromosomal regions.

Abundance and characteristics of the recreational water quality indicator bacteria Escherichia coli and enterococci in gull faeces

USGS Publications Warehouse

Fogarty, L.R.; Haack, S.K.; Wolcott, M.J.; Whitman, R.L.

2003-01-01

Aims: To evaluate the numbers and selected phenotypic and genotypic characteristics of the faecal indicator bacteria Escherichia coli and enterococci in gull faeces at representative Great Lakes swimming beaches in the United States. Methods and Results: E. coli and enterococci were enumerated in gull faeces by membrane filtration. E. coli genotypes (rep-PCR genomic profiles) and E. coli (Vitek?? GNI+) and enterococci (API?? rapid ID 32 Strep and resistance to streptomycin, gentamicin, vancomycin, tetracycline and ampicillin) phenotypes were determined for isolates obtained from gull faeces both early and late in the swimming season. Identical E. coli genotypes were obtained only from single gull faecal samples but most faecal samples yielded more than one genotype (median of eight genotypes for samples with 10 isolates). E. coli isolates from the same site that clustered at ???85% similarity were from the same sampling date and shared phenotypic characteristics, and at this similarity level there was population overlap between the two geographically isolated beach sites. Enterococcus API?? profiles varied with sampling date. Gull enterococci displayed wide variation in antibiotic resistance patterns, and high-level resistance to some antibiotics. Conclusions: Gull faeces could be a major contributor of E. coli (105-109 CFU g-1) and enterococci (104-108 CFU g-1) to Great Lakes recreational waters. E. coli and enterococci in gull faeces are highly variable with respect to their genotypic and phenotypic characteristics and may exhibit temporal or geographic trends in these features. Significance and Impact of the Study: The high degree of variation in genotypic or phenotypic characteristics of E. coli or enterococci populations within gull hosts will require extensive sampling for adequate characterization, and will influence methods that use these characteristics to determine faecal contamination sources for recreational waters.

Escherichia coli and enterococci at beaches in the Grand Traverse Bay, Lake Michigan: Sources, characteristics, and environmental pathways

USGS Publications Warehouse

Haack, S.K.; Fogarty, L.R.; Wright, C.

2003-01-01

This study quantified Escherichia coli(EC) and enterococci (ENT) in beach waters and dominant source materials, correlated these with ambient conditions, and determined selected EC genotypes and ENT phenotypes. Bathing-water ENT criteria were exceeded more frequently than EC criteria, providing conflicting interpretations of water quality. Dominant sources of EC and ENT were bird feces (108/d/bird), storm drains (107/d), and river water (1011/d); beach sands, shallow groundwater and detritus were additional sources. Beach-water EC genotypes and ENT phenotypes formed clusters with those from all source types, reflecting diffuse inputs. Some ENT isolates had phenotypes similar to those of human pathogens and/or exhibited high-level resistance to human-use antibiotics. EC and ENT concentrations were influenced by collection time and wind direction. There was a 48-72-h lag between rainfall and elevated EC concentrations at three southern shoreline beaches, but no such lag at western and eastern shoreline beaches, reflecting the influence of beach orientation with respect to cyclic (3-5 d) summer weather patterns. In addition to local contamination sources and processes, conceptual or predictive models of Great Lakes beach water quality should consider regional weather patterns, lake hydrodynamics, and the influence of monitoring method variables (time of day, frequency).

GSTM1 null polymorphism at the glutathione S-transferase M1 locus: phenotype and genotype studies in patients with primary biliary cirrhosis.

PubMed Central

Davies, M H; Elias, E; Acharya, S; Cotton, W; Faulder, G C; Fryer, A A; Strange, R C

1993-01-01

Studies were carried out to test the hypothesis that the GSTM1 null phenotype at the mu (mu) class glutathione S-transferase 1 locus is associated with an increased predisposition to primary biliary cirrhosis. Starch gel electrophoresis was used to compare the prevalence of GSTM1 null phenotype 0 in patients with end stage primary biliary cirrhosis and a group of controls without evidence of liver disease. The prevalence of GSTM1 null phenotype in the primary biliary cirrhosis and control groups was similar; 39% and 45% respectively. In the primary biliary cirrhosis group all subjects were of the common GSTM1 0, GSTM1 A, GSTM1 B or GSTM1 A, B phenotypes while in the controls, one subject showed an isoform with an anodal mobility compatible with it being a product of the putative GSTM1*3 allele. As the GSTM1 phenotype might be changed by the disease process, the polymerase chain reaction was used to amplify the exon 4-exon 5 region of GSTM1 and show that in 13 control subjects and 11 patients with primary biliary cirrhosis, GSTM1 positive and negative genotypes were associated with corresponding GSTM1 expressing and non-expressing phenotypes respectively. The control subject with GSTM1 3 phenotype showed a positive genotype. Images Figure 1 Figure 2 PMID:8491405

MLL2 mutation detection in 86 patients with Kabuki syndrome: a genotype-phenotype study.

PubMed

Makrythanasis, P; van Bon, B W; Steehouwer, M; Rodríguez-Santiago, B; Simpson, M; Dias, P; Anderlid, B M; Arts, P; Bhat, M; Augello, B; Biamino, E; Bongers, E M H F; Del Campo, M; Cordeiro, I; Cueto-González, A M; Cuscó, I; Deshpande, C; Frysira, E; Izatt, L; Flores, R; Galán, E; Gener, B; Gilissen, C; Granneman, S M; Hoyer, J; Yntema, H G; Kets, C M; Koolen, D A; Marcelis, C l; Medeira, A; Micale, L; Mohammed, S; de Munnik, S A; Nordgren, A; Psoni, S; Reardon, W; Revencu, N; Roscioli, T; Ruiterkamp-Versteeg, M; Santos, H G; Schoumans, J; Schuurs-Hoeijmakers, J H M; Silengo, M C; Toledo, L; Vendrell, T; van der Burgt, I; van Lier, B; Zweier, C; Reymond, A; Trembath, R C; Perez-Jurado, L; Dupont, J; de Vries, B B A; Brunner, H G; Veltman, J A; Merla, G; Antonarakis, S E; Hoischen, A

2013-12-01

Recently, pathogenic variants in the MLL2 gene were identified as the most common cause of Kabuki (Niikawa-Kuroki) syndrome (MIM#147920). To further elucidate the genotype-phenotype correlation, we studied a large cohort of 86 clinically defined patients with Kabuki syndrome (KS) for mutations in MLL2. All patients were assessed using a standardized phenotype list and all were scored using a newly developed clinical score list for KS (MLL2-Kabuki score 0-10). Sequencing of the full coding region and intron-exon boundaries of MLL2 identified a total of 45 likely pathogenic mutations (52%): 31 nonsense, 10 missense and four splice-site mutations, 34 of which were novel. In five additional patients, novel, i.e. non-dbSNP132 variants of clinically unknown relevance, were identified. Patients with likely pathogenic nonsense or missense MLL2 mutations were usually more severely affected (median 'MLL2-Kabuki score' of 6) as compared to the patients without MLL2 mutations (median 'MLL2-Kabuki score' of 5), a significant difference (p < 0.0014). Several typical facial features such as large dysplastic ears, arched eyebrows with sparse lateral third, blue sclerae, a flat nasal tip with a broad nasal root, and a thin upper and a full lower lip were observed more often in mutation positive patients. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Primer in Genetics and Genomics, Article 5-Further Defining the Concepts of Genotype and Phenotype and Exploring Genotype-Phenotype Associations.

PubMed

Wright, Fay; Fessele, Kristen

2017-10-01

As nurses begin to incorporate genetic and genomic sciences into clinical practice, education, and research, it is essential that they have a working knowledge of the terms foundational to the science. The first article in this primer series provided brief definitions of the basic terms (e.g., genetics and genomics) and introduced the concept of phenotype during the discussion of Mendelian inheritance. These terms, however, are inconsistently used in publications and conversations, and the linkage between genotype and phenotype requires clarification. The goal of this fifth article in the series is to elucidate these terms, provide an overview of the research methods used to determine genotype-phenotype associations, and discuss their significance to nursing through examples from the current nursing literature.

Simultaneous improvement of grain yield and protein content in durum wheat by different phenotypic indices and genomic selection.

PubMed

Rapp, M; Lein, V; Lacoudre, F; Lafferty, J; Müller, E; Vida, G; Bozhanova, V; Ibraliu, A; Thorwarth, P; Piepho, H P; Leiser, W L; Würschum, T; Longin, C F H

2018-06-01

Simultaneous improvement of protein content and grain yield by index selection is possible but its efficiency largely depends on the weighting of the single traits. The genetic architecture of these indices is similar to that of the primary traits. Grain yield and protein content are of major importance in durum wheat breeding, but their negative correlation has hampered their simultaneous improvement. To account for this in wheat breeding, the grain protein deviation (GPD) and the protein yield were proposed as targets for selection. The aim of this work was to investigate the potential of different indices to simultaneously improve grain yield and protein content in durum wheat and to evaluate their genetic architecture towards genomics-assisted breeding. To this end, we investigated two different durum wheat panels comprising 159 and 189 genotypes, which were tested in multiple field locations across Europe and genotyped by a genotyping-by-sequencing approach. The phenotypic analyses revealed significant genetic variances for all traits and heritabilities of the phenotypic indices that were in a similar range as those of grain yield and protein content. The GPD showed a high and positive correlation with protein content, whereas protein yield was highly and positively correlated with grain yield. Thus, selecting for a high GPD would mainly increase the protein content whereas a selection based on protein yield would mainly improve grain yield, but a combination of both indices allows to balance this selection. The genome-wide association mapping revealed a complex genetic architecture for all traits with most QTL having small effects and being detected only in one germplasm set, thus limiting the potential of marker-assisted selection for trait improvement. By contrast, genome-wide prediction appeared promising but its performance strongly depends on the relatedness between training and prediction sets.

Identification of a mutation that is associated with the saddle tan and black-and-tan phenotypes in Basset Hounds and Pembroke Welsh Corgis.

PubMed

Dreger, Dayna L; Parker, Heidi G; Ostrander, Elaine A; Schmutz, Sheila M

2013-01-01

The causative mutation for the black-and-tan (a (t) ) phenotype in dogs was previously shown to be a SINE insertion in the 5' region of Agouti Signaling Protein (ASIP). Dogs with the black-and-tan phenotype, as well as dogs with the saddle tan phenotype, genotype as a (t) /_ at this locus. We have identified a 16-bp duplication (g.1875_1890dupCCCCAGGTCAGAGTTT) in an intron of hnRNP associated with lethal yellow (RALY), which segregates with the black-and-tan phenotype in a group of 99 saddle tan and black-and-tan Basset Hounds and Pembroke Welsh Corgis. In these breeds, all dogs with the saddle tan phenotype had RALY genotypes of +/+ or +/dup, whereas dogs with the black-and-tan phenotype were homozygous for the duplication. The presence of an a (y) /_ fawn or e/e red genotype is epistatic to the +/_ saddle tan genotype. Genotypes from 10 wolves and 1 coyote indicated that the saddle tan (+) allele is the ancestral allele, suggesting that black-and-tan is a modification of saddle tan. An additional 95 dogs from breeds that never have the saddle tan phenotype have all three of the possible RALY genotypes. We suggest that a multi-gene interaction involving ASIP, RALY, MC1R, DEFB103, and a yet-unidentified modifier gene is required for expression of saddle tan.

Knowing your genes: does this impact behaviour change?

PubMed

O'Donovan, Clare B; Walsh, Marianne C; Gibney, Michael J; Brennan, Lorraine; Gibney, Eileen R

2017-08-01

It is postulated that knowledge of genotype may be more powerful than other types of personalised information in terms of motivating behaviour change. However, there is also a danger that disclosure of genetic risk may promote a fatalistic attitude and demotivate individuals. The original concept of personalised nutrition (PN) focused on genotype-based tailored dietary advice; however, PN can also be delivered based on assessment of dietary intake and phenotypic measures. Whilst dietitians currently provide PN advice based on diet and phenotype, genotype-based PN advice is not so readily available. The aim of this review is to examine the evidence for genotype-based personalised information on motivating behaviour change, and factors which may affect the impact of genotype-based personalised advice. Recent findings in PN will also be discussed, with respect to a large European study, Food4Me, which investigated the impact of varying levels of PN advice on motivating behaviour change. The researchers reported that PN advice resulted in greater dietary changes compared with general healthy eating advice, but no additional benefit was observed for PN advice based on phenotype and genotype information. Within Food4Me, work from our group revealed that knowledge of MTHFR genotype did not significantly improve intakes of dietary folate. In general, evidence is weak with regard to genotype-based PN advice. For future work, studies should test the impact of PN advice developed on a strong nutrigenetic evidence base, ensure an appropriate study design for the research question asked, and incorporate behaviour change techniques into the intervention.

AB014. Beta-ketothiolase deficiency: phenotype, genotype and outcome of 48 Vietnamese patients

PubMed Central

Nguyen, Khanh Ngoc; Nguyen, Hoan Thi; Can, Ngoc Thi Bich; Do, Mai Thi Thanh; Bui, Thao Phuong; Fukao, Toshiyuki; Vu, Dung Chi

2017-01-01

Background Beta-ketothiolase deficiency (BKT) is an inherited metabolic disease of isoleucine and ketone body caused by mutations in the T2 gene. It is a rare disease with over 100 patients reported worldwide. We aimed to describe phenotypes and genotypes and to evaluate outcomes of Vietnamese patients with BKT. Methods Patients who were diagnosed with BKT, and followed up at National Children Hospital from January 2015 to June 2017 were enrolled. Results Forty-eight patients from 40 different and unrelated families were diagnosed through high risk screening in Vietnam. Forty-six patients (96%) presented with acute episodes of intermittent ketotic acidosis (pH <7.1, increased anion gap), and were asymptomatic between episodes. Ages of onset were between 6 and 18 months. Characteristics of metabolic chemistry revealed elevated urinary 2-methylacetoacetate, 2-methyl-3-hydroxybutyrate, tiglylglycine, and plasma C5:1 and C5:OH carnitines. We identified 8 different mutations with 9 kinds of genotypes. The common mutations of T2 gene were p.R208X and IVS10-1g>c (85%). Five novel mutations were identified (IVS10-1g>c, c.1032_1033insA, p.S284N, exon 6 -11del, and c.163_167delinsAA). Eight out of nine genotypes were null mutations. There was no correlation between genotypes and phenotypes. The outcome was good in most patients with 83% had complete recovery, 7% mental consequences, and 12% death. All patients had normal growth rate according to growth chart by World Health Organization (WHO) 2007. Conclusions BKT is a common inborn error of metabolism in Vietnam with good outcome in most patients. A newborn screening program for BKT may have a high detection rate in Vietnam.

Presence of autism, hyperserotonemia, and severe expressive language impairment in Williams-Beuren syndrome.

PubMed

Tordjman, Sylvie; Anderson, George M; Cohen, David; Kermarrec, Solenn; Carlier, Michèle; Touitou, Yvan; Saugier-Veber, Pascale; Lagneaux, Céline; Chevreuil, Claire; Verloes, Alain

2013-08-23

Deletion of the Williams-Beuren syndrome (WBS) critical region (WBSCR), at 7q11.23, causes a developmental disorder commonly characterized by hypersociability and excessive talkativeness and often considered the opposite behavioral phenotype to autism. Duplication of the WBSCR leads to severe delay in expressive language. Gene-dosage effects on language development at 7q11.23 have been hypothesized. Molecular characterization of the WBSCR was performed by fluorescence in situ hybridization and high-resolution single-nucleotide polymorphism array in two individuals with severe autism enrolled in a genetic study of autism who showed typical WBS facial dysmorphism on systematic clinical genetic examination. The serotonin transporter promoter polymorphism (5-HTTLPR, locus SLC6A4) was genotyped. Platelet serotonin levels and urinary 6-sulfatoxymelatonin excretion were measured. Behavioral and cognitive phenotypes were examined. The two patients had common WBSCR deletions between proximal and medial low copy repeat clusters, met diagnostic criteria for autism and displayed severe impairment in communication, including a total absence of expressive speech. Both patients carried the 5-HTTLPR ss genotype and exhibited platelet hyperserotonemia and low melatonin production. Our observations indicate that behaviors and neurochemical phenotypes typically associated with autism can occur in patients with common WBSCR deletions. The results raise intriguing questions about phenotypic heterogeneity in WBS and regarding genetic and/or environmental factors interacting with specific genes at 7q11.23 sensitive to dosage alterations that can influence the development of social communication skills. Thus, the influence of WBSCR genes on social communication expression might be dramatically modified by other genes, such as 5-HTTLPR, known to influence the severity of social communication impairments in autism, or by environmental factors, such as hyperserotonemia, given that hyperserotonemia is found in WBS associated with autism but not in WBS without autism. In this regard, WBS provides a potentially fruitful model with which to develop integrated genetic, cognitive, behavioral and neurochemical approaches to study genotype-phenotype correlations, possible gene-environment interactions and genetic background effects. The results underscore the importance of considering careful clinical and molecular genetic examination of individuals diagnosed with autism.

Striatal response to reward anticipation: evidence for a systems-level intermediate phenotype for schizophrenia.

PubMed

Grimm, Oliver; Heinz, Andreas; Walter, Henrik; Kirsch, Peter; Erk, Susanne; Haddad, Leila; Plichta, Michael M; Romanczuk-Seiferth, Nina; Pöhland, Lydia; Mohnke, Sebastian; Mühleisen, Thomas W; Mattheisen, Manuel; Witt, Stephanie H; Schäfer, Axel; Cichon, Sven; Nöthen, Markus; Rietschel, Marcella; Tost, Heike; Meyer-Lindenberg, Andreas

2014-05-01

Attenuated ventral striatal response during reward anticipation is a core feature of schizophrenia that is seen in prodromal, drug-naive, and chronic schizophrenic patients. Schizophrenia is highly heritable, raising the possibility that this phenotype is related to the genetic risk for the disorder. To examine a large sample of healthy first-degree relatives of schizophrenic patients and compare their neural responses to reward anticipation with those of carefully matched controls without a family psychiatric history. To further support the utility of this phenotype, we studied its test-retest reliability, its potential brain structural contributions, and the effects of a protective missense variant in neuregulin 1 (NRG1) linked to schizophrenia by meta-analysis (ie, rs10503929). Examination of a well-established monetary reward anticipation paradigm during functional magnetic resonance imaging at a university hospital; voxel-based morphometry; test-retest reliability analysis of striatal activations in an independent sample of 25 healthy participants scanned twice with the same task; and imaging genetics analysis of the control group. A total of 54 healthy first-degree relatives of schizophrenic patients and 80 controls matched for demographic, psychological, clinical, and task performance characteristics were studied. Blood oxygen level-dependent response during reward anticipation, analysis of intraclass correlations of functional contrasts, and associations between striatal gray matter volume and NRG1 genotype. Compared with controls, healthy first-degree relatives showed a highly significant decrease in ventral striatal activation during reward anticipation (familywise error-corrected P < .03 for multiple comparisons across the whole brain). Supplemental analyses confirmed that the identified systems-level functional phenotype is reliable (with intraclass correlation coefficients of 0.59-0.73), independent of local gray matter volume (with no corresponding group differences and no correlation to function, and with all uncorrected P values >.05), and affected by the NRG1 genotype (higher striatal responses in controls with the protective rs10503929 C allele; familywise error-corrected P < .03 for ventral striatal response). Healthy first-degree relatives of schizophrenic patients show altered striatal activation during reward anticipation in a directionality and localization consistent with prior patient findings. This provides evidence for a functional neural system mechanism related to familial risk. The phenotype can be assessed reliably, is independent of alterations in striatal structure, and is influenced by a schizophrenia candidate gene variant in NRG1. These data encourage us to further investigate the genetic and molecular contributions to this phenotype.

Dopamine D4 Receptor Gene Polymorphism in a Sample of Egyptian Children With Attention-Deficit Hyperactivity Disorder (ADHD).

PubMed

ElBaz Mohamed, Farida; Kamal, Tarek Mostafa; Zahra, Sally Soliman; Khfagy, Mona Abdel Hakiem; Youssef, Azza Mohamed

2017-02-01

This study aimed to detect DRD4 receptor gene polymorphisms in attention-deficit hyperactivity disorder (ADHD) children and to correlate their phenotype-genotype. Fifty children with ADHD were diagnosed by Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria and were subjected to Conners Parent Rating Scale. All cases and controls were subjected to history taking, physical examination, IQ assessment, and dopamine receptor D4 (DRD4) exon 3 genotyping. The 7-repeat allele was present only in controls, whereas 2-repeat allele was present in the ADHD children (heterozygous 2-repeat allele in 16% and homozygous in 26% of cases). Eight percent of cases had homozygous 4-repeat allele vs 28% of controls, whereas 10% of cases had heterozygous 4-repeat allele vs 6% of controls, with its predominance in controls. The 2-repeat and 4-repeat alleles have been associated with more inattention, hyperactivity, and impulsivity phenotypes. In conclusion, children with ADHD had a significant presence of the 2-repeat allele and absence of the 7-repeat allele.

Recurrent mutations in the CDKL5 gene: genotype-phenotype relationships.

PubMed

Bahi-Buisson, Nadia; Villeneuve, Nathalie; Caietta, Emilie; Jacquette, Aurélia; Maurey, Helene; Matthijs, Gert; Van Esch, Hilde; Delahaye, Andrée; Moncla, Anne; Milh, Mathieu; Zufferey, Flore; Diebold, Bertrand; Bienvenu, Thierry

2012-07-01

Mutations in the cyclin-dependent kinase-like 5 gene (CDKL5) have been described in epileptic encephalopathies in females with infantile spasms with features that overlap with Rett syndrome. With more than 80 reported patients, the phenotype of CDKL5-related encephalopathy is well-defined. The main features consist of seizures starting before 6 months of age, severe intellectual disability with absent speech and hand stereotypies and deceleration of head growth, which resembles Rett syndrome. However, some clinical discrepancies suggested the influence of genetics and/or environmental factors. No genotype-phenotype correlation has been defined and thus there is a need to examine individual mutations. In this study, we analyzed eight recurrent CDKL5 mutations to test whether the clinical phenotype of patients with the same mutation is similar and whether patients with specific CDKL5 mutations have a milder phenotype than those with other CDKL5 mutations. Patients bearing missense mutations in the ATP binding site such as the p.Ala40Val mutation typically walked unaided, had normocephaly, better hand use ability, and less frequent refractory epilepsy when compared to girls with other CDKL5 mutations. In contrast, patients with mutations in the kinase domain (such as p.Arg59X, p.Arg134X, p.Arg178Trp/Pro/Gln, or c.145 + 2T > C) and frameshift mutations in the C-terminal region (such as c.2635_2636delCT) had a more severe phenotype with infantile spasms, refractory epileptic encephalopathy, absolute microcephaly, and inability to walk. It is important for clinicians to have this information when such patients are diagnosed. Copyright © 2012 Wiley Periodicals, Inc.

Variation in Adult Plant Phenotypes and Partitioning among Seed and Stem-Borne Roots across Brachypodium distachyon Accessions to Exploit in Breeding Cereals for Well-Watered and Drought Environments.

PubMed

Chochois, Vincent; Vogel, John P; Rebetzke, Gregory J; Watt, Michelle

2015-07-01

Seedling roots enable plant establishment. Their small phenotypes are measured routinely. Adult root systems are relevant to yield and efficiency, but phenotyping is challenging. Root length exceeds the volume of most pots. Field studies measure partial adult root systems through coring or use seedling roots as adult surrogates. Here, we phenotyped 79 diverse lines of the small grass model Brachypodium distachyon to adults in 50-cm-long tubes of soil with irrigation; a subset of 16 lines was droughted. Variation was large (total biomass, ×8; total root length [TRL], ×10; and root mass ratio, ×6), repeatable, and attributable to genetic factors (heritabilities ranged from approximately 50% for root growth to 82% for partitioning phenotypes). Lines were dissected into seed-borne tissues (stem and primary seminal axile roots) and stem-borne tissues (tillers and coleoptile and leaf node axile roots) plus branch roots. All lines developed one seminal root that varied, with branch roots, from 31% to 90% of TRL in the well-watered condition. With drought, 100% of TRL was seminal, regardless of line because nodal roots were almost always inhibited in drying topsoil. Irrigation stimulated nodal roots depending on genotype. Shoot size and tillers correlated positively with roots with irrigation, but partitioning depended on genotype and was plastic with drought. Adult root systems of B. distachyon have genetic variation to exploit to increase cereal yields through genes associated with partitioning among roots and their responsiveness to irrigation. Whole-plant phenotypes could enhance gain for droughted environments because root and shoot traits are coselected. © 2015 American Society of Plant Biologists. All Rights Reserved.

Molecular cytogenetics characterization of seven small supernumerary marker chromosomes derived from chromosome 19: Genotype-phenotype correlation and review of the literature.

PubMed

Recalcati, Maria Paola; Bonati, Maria Teresa; Beltrami, Nicola; Cardarelli, Laura; Catusi, Ilaria; Costa, Asia; Garzo, Maria; Mammi, Isabella; Mattina, Teresa; Nalesso, Elisa; Nardone, Anna Maria; Postorivo, Diana; Sajeva, Anna; Varricchio, Aminta; Verri, Annapia; Villa, Nicoletta; Larizza, Lidia; Giardino, Daniela

2018-03-01

Only a few subjects carrying supernumerary marker chromosomes derived from 19 chromosome (sSMC(19)) have been described to date and for a small portion of them the genic content has been defined at the molecular level. We present seven new different sSMCs(19) identified in eight individuals, seven of whom unrelated. The presence of the sSMC is associated with a clinical phenotype in five subjects, while the other three carriers, two of whom related, are normal. All sSMCs(19) have been characterized by means of conventional and molecular cytogenetics. We compare the sSMCs(19) carriers with a clinical phenotype to already described patients with gains (sSMCs or microduplications) of overlapping genomic regions with the aim to deepen the pathogenicity of the encountered imbalances and to assess the role of the involved genes on the phenotype. The present work supports the correlation between the gain of some chromosome 19 critical regions and specific phenotypes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The contribution of individual and pairwise combinations of SNPs in the APOA1 and APOC3 genes to interindividual HDL-C variability.

PubMed

Brown, C M; Rea, T J; Hamon, S C; Hixson, J E; Boerwinkle, E; Clark, A G; Sing, C F

2006-07-01

Apolipoproteins (apo) A-I and C-III are components of high-density lipoprotein-cholesterol (HDL-C), a quantitative trait negatively correlated with risk of cardiovascular disease (CVD). We analyzed the contribution of individual and pairwise combinations of single nucleotide polymorphisms (SNPs) in the APOA1/APOC3 genes to HDL-C variability to evaluate (1) consistency of published single-SNP studies with our single-SNP analyses; (2) consistency of single-SNP and two-SNP phenotype-genotype relationships across race-, gender-, and geographical location-dependent contexts; and (3) the contribution of single SNPs and pairs of SNPs to variability beyond that explained by plasma apo A-I concentration. We analyzed 45 SNPs in 3,831 young African-American (N=1,858) and European-American (N=1,973) females and males ascertained by the Coronary Artery Risk Development in Young Adults (CARDIA) study. We found three SNPs that significantly impact HDL-C variability in both the literature and the CARDIA sample. Single-SNP analyses identified only one of five significant HDL-C SNP genotype relationships in the CARDIA study that was consistent across all race-, gender-, and geographical location-dependent contexts. The other four were consistent across geographical locations for a particular race-gender context. The portion of total phenotypic variance explained by single-SNP genotypes and genotypes defined by pairs of SNPs was less than 3%, an amount that is miniscule compared to the contribution explained by variability in plasma apo A-I concentration. Our findings illustrate the impact of context-dependence on SNP selection for prediction of CVD risk factor variability.

Peripheral neuropathy in genetically characterized patients with mitochondrial disorders: A study from south India.

PubMed

Bindu, Parayil Sankaran; Govindaraju, Chikanna; Sonam, Kothari; Nagappa, Madhu; Chiplunkar, Shwetha; Kumar, Rakesh; Gayathri, Narayanappa; Bharath, M M Srinivas; Arvinda, Hanumanthapura R; Sinha, Sanjib; Khan, Nahid Akthar; Govindaraj, Periyasamy; Nunia, Vandana; Paramasivam, Arumugam; Thangaraj, Kumarasamy; Taly, Arun B

2016-03-01

There are relatively few studies, which focus on peripheral neuropathy in large cohorts of genetically characterized patients with mitochondrial disorders. This study sought to analyze the pattern of peripheral neuropathy in a cohort of patients with mitochondrial disorders. The study subjects were derived from a cohort of 52 patients with a genetic diagnosis of mitochondrial disorders seen over a period of 8 years (2006-2013). All patients underwent nerve conduction studies and those patients with abnormalities suggestive of peripheral neuropathy were included in the study. Their phenotypic features, genotype, pattern of peripheral neuropathy and nerve conduction abnormalities were analyzed retrospectively. The study cohort included 18 patients (age range: 18 months-50 years, M:F- 1.2:1).The genotype included mitochondrial DNA point mutations (n=11), SURF1 mutations (n=4) and POLG1(n=3). Axonal neuropathy was noted in 12 patients (sensori-motor:n=4; sensory:n=4; motor:n=4) and demyelinating neuropathy in 6. Phenotype-genotype correlations revealed predominant axonal neuropathy in mtDNA point mutations and demyelinating neuropathy in SURF1. Patients with POLG related disorders had both sensory ataxic neuropathy and axonal neuropathy. A careful analysis of the family history, clinical presentation, biochemical, histochemical and structural analysis may help to bring out the mitochondrial etiology in patients with peripheral neuropathy and may facilitate targeted gene testing. Presence of demyelinating neuropathy in Leigh's syndrome may suggest underlying SURF1 mutations. Sensory ataxic neuropathy with other mitochondrial signatures should raise the possibility of POLG related disorder. Copyright © 2015. Published by Elsevier B.V.

Genotype by energy expenditure interaction with metabolic syndrome traits: the Portuguese healthy family study.

PubMed

Santos, Daniel M V; Katzmarzyk, Peter T; Diego, Vincent P; Souza, Michele C; Chaves, Raquel N; Blangero, John; Maia, José A R

2013-01-01

Moderate-to-high levels of physical activity are established as preventive factors in metabolic syndrome development. However, there is variability in the phenotypic expression of metabolic syndrome under distinct physical activity conditions. In the present study we applied a Genotype X Environment interaction method to examine the presence of GxEE interaction in the phenotypic expression of metabolic syndrome. A total of 958 subjects, from 294 families of The Portuguese Healthy Family study, were included in the analysis. Total daily energy expenditure was assessed using a 3 day physical activity diary. Six metabolic syndrome related traits, including waist circumference, systolic blood pressure, glucose, HDL cholesterol, total cholesterol and triglycerides, were measured and adjusted for age and sex. GxEE examination was performed on SOLAR 4.3.1. All metabolic syndrome indicators were significantly heritable. The GxEE interaction model fitted the data better than the polygenic model (p<0.001) for waist circumference, systolic blood pressure, glucose, total cholesterol and triglycerides. For waist circumference, glucose, total cholesterol and triglycerides, the significant GxEE interaction was due to rejection of the variance homogeneity hypothesis. For waist circumference and glucose, GxEE was also significant by the rejection of the genetic correlation hypothesis. The results showed that metabolic syndrome traits expression is significantly influenced by the interaction established between total daily energy expenditure and genotypes. Physical activity may be considered an environmental variable that promotes metabolic differences between individuals that are distinctively active.

The evolution of polyandry: patterns of genotypic variation in female mating frequency, male fertilization success and a test of the sexy-sperm hypothesis.

PubMed

Simmons, L W

2003-07-01

The sexy-sperm hypothesis predicts that females obtain indirect benefits for their offspring via polyandy, in the form of increased fertilization success for their sons. I use a quantitative genetic approach to test the sexy-sperm hypothesis using the field cricket Teleogryllus oceanicus. Previous studies of this species have shown considerable phenotypic variation in fertilization success when two or more males compete. There were high broad-sense heritabilities for both paternity and polyandry. Patterns of genotypic variance were consistent with X-linked inheritance and/or maternal effects on these traits. The genetic architecture therefore precludes the evolution of polyandry via a sexy-sperm process. Thus the positive genetic correlation between paternity in sons and polyandry in daughters predicted by the sexy-sperm hypothesis was absent. There was significant heritable variation in the investment by females in ovaries and by males in the accessory gland. Surprisingly there was a very strong genetic correlation between these two traits. The significance of this genetic correlation for the coevolution of male seminal products and polyandry is discussed.

Genotype and Ancestry Modulate Brain's DAT Availability in Healthy Humans

PubMed Central

Shumay, Elena; Chen, John; Fowler, Joanna S.; Volkow, Nora D.

2011-01-01

The dopamine transporter (DAT) is a principal regulator of dopaminergic neurotransmission and its gene (the SLC6A3) is a strong biological candidate gene for various behavioral- and neurological disorders. Intense investigation of the link between the SLC6A3 polymorphisms and behavioral phenotypes yielded inconsistent and even contradictory results. Reliance on objective brain phenotype measures, for example, those afforded by brain imaging, might critically improve detection of DAT genotype-phenotype association. Here, we tested the relationship between the DAT brain availability and the SLC6A3 genotypes using an aggregate sample of 95 healthy participants of several imaging studies. These studies employed positron emission tomography (PET) with [11C]cocaine wherein the DAT availability was estimated as Bmax/Kd; while the genotype values were obtained on two repeat polymorphisms - 3-UTR- and intron 8- VNTRs. The main findings are the following: 1) both polymorphisms analyzed as single genetic markers and in combination (haplotype) modulate DAT density in midbrain; 2) ethnic background and age influence the strength of these associations; and 3) age-related changes in DAT availability differ in the 3-UTR and intron8 – genotype groups. PMID:21826203

Genotype and ancestry modulate brain's DAT availability in healthy humans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shumay, E.; Shumay, E.; Chen, J.

2011-08-01

The dopamine transporter (DAT) is a principal regulator of dopaminergic neurotransmission and its gene (the SLC6A3) is a strong biological candidate gene for various behavioral- and neurological disorders. Intense investigation of the link between the SLC6A3 polymorphisms and behavioral phenotypes yielded inconsistent and even contradictory results. Reliance on objective brain phenotype measures, for example, those afforded by brain imaging, might critically improve detection of DAT genotype-phenotype association. Here, we tested the relationship between the DAT brain availability and the SLC6A3 genotypes using an aggregate sample of 95 healthy participants of several imaging studies. These studies employed positron emission tomography (PET)more » with [{sup 11}C] cocaine wherein the DAT availability was estimated as Bmax/Kd; while the genotype values were obtained on two repeat polymorphisms - 3-UTR- and intron 8- VNTRs. The main findings are the following: (1) both polymorphisms analyzed as single genetic markers and in combination (haplotype) modulate DAT density in midbrain; (2) ethnic background and age influence the strength of these associations; and (3) age-related changes in DAT availability differ in the 3-UTR and intron8 - genotype groups.« less

Habitat conditions and phenological tree traits overrule the influence of tree genotype in the needle mycobiome-Picea glauca system at an arctic treeline ecotone.

PubMed

Eusemann, Pascal; Schnittler, Martin; Nilsson, R Henrik; Jumpponen, Ari; Dahl, Mathilde B; Würth, David G; Buras, Allan; Wilmking, Martin; Unterseher, Martin

2016-09-01

Plant-associated mycobiomes in extreme habitats are understudied and poorly understood. We analysed Illumina-generated ITS1 sequences from the needle mycobiome of white spruce (Picea glauca) at the northern treeline in Alaska (USA). Sequences were obtained from the same DNA that was used for tree genotyping. In the present study, fungal metabarcoding and tree microsatellite data were compared for the first time. In general, neighbouring trees shared more fungal taxa with each other than trees growing in further distance. Mycobiomes correlated strongly with phenological host traits and local habitat characteristics contrasting a dense forest stand with an open treeline site. Genetic similarity between trees did not influence fungal composition and no significant correlation existed between needle mycobiome and tree genotype. Our results suggest the pronounced influence of local habitat conditions and phenotypic tree traits on needle-inhabiting fungi. By contrast, the tree genetic identity cannot be benchmarked as a dominant driver for needle-inhabiting mycobiomes, at least not for white spruce in this extreme environment. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

A chondrodysplasia family produced by mutations in the diastrophic dysplasia sulfate transporter gene: Genotype/phenotype correlations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Superti-Furga, A.; Steinmann, B.; Gitzelmann, R.

1996-05-03

Achondrogenesis type 1B (ACG-1B), atelosteogenesis type 2 (AO-2), and diastrophic dysplasia (DTD) are recessively inherited chondrodysplasia of decreasing severity caused by mutations in the diastrophic dysplasia sulfate transporter (DTDST) gene on chromosome 5. In these conditions, sulfate transport across the cell membrane is impaired which results in insufficient sulfation of cartilage proteoglycans and thus in an abnormally low sulfate content of cartilage. The severity of the phenotype correlates well with the predicted effect of the underlying DTDST mutations: homozygosity or compound heterozygosity for stop codons or transmembrane domain substitutions mostly result in achondrogenesis type 1B, while other structural or regulatorymore » mutations usually result in one of the less severe phenotypes. The chondrodysplasia arising at the DTDST locus constitute a bone dysplasia family with recessive inheritance. 28 refs., 2 tabs.« less

Comparison of molecular breeding values based on within- and across-breed training in beef cattle.

PubMed

Kachman, Stephen D; Spangler, Matthew L; Bennett, Gary L; Hanford, Kathryn J; Kuehn, Larry A; Snelling, Warren M; Thallman, R Mark; Saatchi, Mahdi; Garrick, Dorian J; Schnabel, Robert D; Taylor, Jeremy F; Pollak, E John

2013-08-16

Although the efficacy of genomic predictors based on within-breed training looks promising, it is necessary to develop and evaluate across-breed predictors for the technology to be fully applied in the beef industry. The efficacies of genomic predictors trained in one breed and utilized to predict genetic merit in differing breeds based on simulation studies have been reported, as have the efficacies of predictors trained using data from multiple breeds to predict the genetic merit of purebreds. However, comparable studies using beef cattle field data have not been reported. Molecular breeding values for weaning and yearling weight were derived and evaluated using a database containing BovineSNP50 genotypes for 7294 animals from 13 breeds in the training set and 2277 animals from seven breeds (Angus, Red Angus, Hereford, Charolais, Gelbvieh, Limousin, and Simmental) in the evaluation set. Six single-breed and four across-breed genomic predictors were trained using pooled data from purebred animals. Molecular breeding values were evaluated using field data, including genotypes for 2227 animals and phenotypic records of animals born in 2008 or later. Accuracies of molecular breeding values were estimated based on the genetic correlation between the molecular breeding value and trait phenotype. With one exception, the estimated genetic correlations of within-breed molecular breeding values with trait phenotype were greater than 0.28 when evaluated in the breed used for training. Most estimated genetic correlations for the across-breed trained molecular breeding values were moderate (> 0.30). When molecular breeding values were evaluated in breeds that were not in the training set, estimated genetic correlations clustered around zero. Even for closely related breeds, within- or across-breed trained molecular breeding values have limited prediction accuracy for breeds that were not in the training set. For breeds in the training set, across- and within-breed trained molecular breeding values had similar accuracies. The benefit of adding data from other breeds to a within-breed training population is the ability to produce molecular breeding values that are more robust across breeds and these can be utilized until enough training data has been accumulated to allow for a within-breed training set.

ADIPOQ single nucleotide polymorphism: Association with adiponectin and lipoproteins levels restricted to men

PubMed Central

Tureck, Luciane Viater; Leite, Neiva; Souza, Ricardo Lehtonen Rodrigues; da Silva Timossi, Luciana; Osiecki, Ana Claudia Vecchi; Osiecki, Raul; Alle, Lupe Furtado

2015-01-01

Adiponectin is an adipokine inversely correlated with obesity, which has beneficial effect on insulin resistance and lipid metabolism. Considering its potential as a therapeutic target in the metabolic disorder contexts, and in order to add knowledge in the area, our study evaluated the ADIPOQ 276G > T polymorphism effect on adiponectin levels, and on lipoproteins of clinical interest in a population sample composed of 211 healthy individuals. Significant effects were observed only among men: the carriers of heterozygous genotype (GT) showed high levels of adiponectin (p = 0.018), while the rare homozygous genotype (TT) gave its carriers a negative phenotype, represented by higher levels of low density lipoprotein cholesterol (LDL-C) (p = 0.004 and p = 0.005) and total cholesterol (TC) (p = 0.010 and p = 0.005) compared to carriers of other genotypes (GG and GT respectively), the independent effect of SNP on LDL-C and TC levels was confirmed by multiple regression analysis (p = 0.008 and p = 0.044). We found no evidence of correlation between circulating adiponectin levels and biochemical markers, which suggests, therefore, an SNP 276G > T independent effect on adiponectin levels and on lipoprotein metabolism in men enrolled in this study. PMID:26137445

The division of labor: genotypic versus phenotypic specialization.

PubMed

Wahl, L M

2002-07-01

A model of the division of labor in simple evolving systems is explored to compare two strategies evident in natural populations: phenotypic specialization (such as differentiation by regulated gene expression) and genotypic specialization (such as co-infection by complementary covirus populations). While genotypic specialization is vulnerable to the chance extinction of an essential specialist type and to parasitism, phenotypic specialization is able to overcome these hurdles. When simple spatial effects are included, phenotypic specialization has further benefits, protecting against destructive dynamic patterns. Many of the advantages of phenotypic specialization, however, can only be realized when a high degree of relatedness within groups is ensured.

Further insight into the phenotype associated with a mutation in the ORC6 gene, causing Meier-Gorlin syndrome 3.

PubMed

Shalev, Stavit Allon; Khayat, Morad; Etty, Daniel-Spiegl; Elpeleg, Orly

2015-03-01

Mutations in genes encoding the origin recognition complex subunits cause Meier-Gorlin syndrome. The disease manifests a triad of short stature, small ears, and small and/or absent patellae with variable expressivity. We report on the identification of a homozygous deleterious mutation in the ORC6 gene in previously described fetuses at the severe end of the Meier-Gorlin spectrum. The phenotype included severe intrauterine growth retardation, dislocation of knees, gracile bones, clubfeet, and small mandible and chest. To date, the clinical presentation of ORC6-associated Meier-Gorlin syndrome has been mild compared to other the phenotype associated with other loci. The present report expands the clinical phenotype associated with ORC6 mutations to include severely abnormal embryological development suggesting a possible genotype-phenotype correlation. © 2015 Wiley Periodicals, Inc.

Phenotypes of organ involvement in sarcoidosis.

PubMed

Schupp, Jonas Christian; Freitag-Wolf, Sandra; Bargagli, Elena; Mihailović-Vučinić, Violeta; Rottoli, Paola; Grubanovic, Aleksandar; Müller, Annegret; Jochens, Arne; Tittmann, Lukas; Schnerch, Jasmin; Olivieri, Carmela; Fischer, Annegret; Jovanovic, Dragana; Filipovic, Snežana; Videnovic-Ivanovic, Jelica; Bresser, Paul; Jonkers, René; O'Reilly, Kate; Ho, Ling-Pei; Gaede, Karoline I; Zabel, Peter; Dubaniewicz, Anna; Marshall, Ben; Kieszko, Robert; Milanowski, Janusz; Günther, Andreas; Weihrich, Anette; Petrek, Martin; Kolek, Vitezslav; Keane, Michael P; O'Beirne, Sarah; Donnelly, Seamas; Haraldsdottir, Sigridur Olina; Jorundsdottir, Kristin B; Costabel, Ulrich; Bonella, Francesco; Wallaert, Benoît; Grah, Christian; Peroš-Golubičić, Tatjana; Luisetti, Mauritio; Kadija, Zamir; Pabst, Stefan; Grohé, Christian; Strausz, János; Vašáková, Martina; Sterclova, Martina; Millar, Ann; Homolka, Jiří; Slováková, Alena; Kendrick, Yvonne; Crawshaw, Anjali; Wuyts, Wim; Spencer, Lisa; Pfeifer, Michael; Valeyre, Dominique; Poletti, Venerino; Wirtz, Hubertus; Prasse, Antje; Schreiber, Stefan; Krawczak, Michael; Müller-Quernheim, Joachim

2018-01-01

Sarcoidosis is a highly variable, systemic granulomatous disease of hitherto unknown aetiology. The GenPhenReSa (Genotype-Phenotype Relationship in Sarcoidosis) project represents a European multicentre study to investigate the influence of genotype on disease phenotypes in sarcoidosis.The baseline phenotype module of GenPhenReSa comprised 2163 Caucasian patients with sarcoidosis who were phenotyped at 31 study centres according to a standardised protocol.From this module, we found that patients with acute onset were mainly female, young and of Scadding type I or II. Female patients showed a significantly higher frequency of eye and skin involvement, and complained more of fatigue. Based on multidimensional correspondence analysis and subsequent cluster analysis, patients could be clearly stratified into five distinct, yet undescribed, subgroups according to predominant organ involvement: 1) abdominal organ involvement, 2) ocular-cardiac-cutaneous-central nervous system disease involvement, 3) musculoskeletal-cutaneous involvement, 4) pulmonary and intrathoracic lymph node involvement, and 5) extrapulmonary involvement.These five new clinical phenotypes will be useful to recruit homogenous cohorts in future biomedical studies. Copyright ©ERS 2018.

Screening of melon genotypes for resistance to vegetable leafminer and your phenotypic correlations with colorimetry.

PubMed

Oliveira, Frederico I C DE; Fiege, Leonardo B C; Celin, Elaine F; Innecco, Renato; Nunes, Glauber H S; Aragão, Fernando A S DE

2017-01-01

Melon is one of the most important vegetable crops in the world. With short cycle in a system of phased planting, phytosanitary control is compromised, and a great volume of agricultural chemicals is used to control vegetable leafminer. Genetic control is an ideal alternative to avoid the damage caused by this insect. Thus, the aim of this study was to evaluate Cucumis accessions in regard to resistance to leafminer and correlate the variables analyzed. Fifty-four accessions and four commercial hybrids of melon were tested. The study was divided into two experiments: with and with no choice. The following characteristics were evaluated: with choice, in field - subjective score based on the infestation and the number of mines per leaf; and with no choice, in cage - number of mines per leaf, chlorophyll content, and leaf colorimetry. The results showed variability among the accessions and some genotypes showed favorable results for resistance in both experiments. There was correlation between the two variables in the experiment in the field. The accessions CNPH 11-282, CNPH 06-1047, and CNPH 11-1077 are the most recommended for future breeding programs with aim on introgression of resistance to vegetable leafminer in melon.

Seed maturation associated transcriptional programs and regulatory networks underlying genotypic difference in seed dormancy and size/weight in wheat (Triticum aestivum L.).

PubMed

Yamasaki, Yuji; Gao, Feng; Jordan, Mark C; Ayele, Belay T

2017-09-16

Maturation forms one of the critical seed developmental phases and it is characterized mainly by programmed cell death, dormancy and desiccation, however, the transcriptional programs and regulatory networks underlying acquisition of dormancy and deposition of storage reserves during the maturation phase of seed development are poorly understood in wheat. The present study performed comparative spatiotemporal transcriptomic analysis of seed maturation in two wheat genotypes with contrasting seed weight/size and dormancy phenotype. The embryo and endosperm tissues of maturing seeds appeared to exhibit genotype-specific temporal shifts in gene expression profile that might contribute to the seed phenotypic variations. Functional annotations of gene clusters suggest that the two tissues exhibit distinct but genotypically overlapping molecular functions. Motif enrichment predicts genotypically distinct abscisic acid (ABA) and gibberellin (GA) regulated transcriptional networks contribute to the contrasting seed weight/size and dormancy phenotypes between the two genotypes. While other ABA responsive element (ABRE) motifs are enriched in both genotypes, the prevalence of G-box-like motif specifically in tissues of the dormant genotype suggests distinct ABA mediated transcriptional mechanisms control the establishment of dormancy during seed maturation. In agreement with this, the bZIP transcription factors that co-express with ABRE enriched embryonic genes differ with genotype. The enrichment of SITEIIATCYTC motif specifically in embryo clusters of maturing seeds irrespective of genotype predicts a tissue specific role for the respective TCP transcription factors with no or minimal contribution to the variations in seed dormancy. The results of this study advance our understanding of the seed maturation associated molecular mechanisms underlying variation in dormancy and weight/size in wheat seeds, which is a critical step towards the designing of molecular strategies for enhancing seed yield and quality.

Genotypic variability for root/shoot parameters under water stress in some advanced lines of cotton (Gossypium hirsutum L.).

PubMed

Riaz, M; Farooq, J; Sakhawat, G; Mahmood, A; Sadiq, M A; Yaseen, M

2013-02-27

Research pertaining to genetic variability parameters, heritability, and genotypic, phenotypic, simple, and environmental correlations for various seedling traits in five elite advanced cotton (Gossypium hirsutum L.) lines (FH-113, FH-114, FH-941, FH-942, and FH-2015) and one check (CIM-496) was carried out during October and November 2010 under greenhouse conditions at the Cotton Research Institute (Faisalabad, Pakistan). Material was raised in plastic tubes with a randomized complete block design replicated three times. Three drought shocks were applied by withholding water from the tube-sown plants for 8-, 10-, and 12-day intervals. After 60 days of sowing, data on root/shoot traits like root length (cm), shoot length (cm), root weight (g), shoot fresh weight (g), lateral root number, root dry weight (g) shoot dry weight (g), and total plant weight (g) were recorded. Considerable genotypic variations existed between genotypes for all seedling characters. Higher broad-sense heritability estimates were found for all traits studied. Maximum broad-sense heritability coupled with high genetic advance in root length (0.99, 17.34), lateral root number (0.91, 2.89), and shoot length (0.90, 4.35) suggested a potential for genetic improvement through breeding and selection. The correlation coefficients among root length, shoot length, root dry weight, fresh shoot weight, and total plant weight were positively and significantly correlated; thus, they can be selected simultaneously as drought tolerance selection indexes owing to the absence of undesired relationships. Genotypes FH-942 and FH-113 had the lowest excised leaf water loss during the first 4 h and also for the next 4 h. Therefore, these two advanced lines (FH-942 and FH-113) with high initial water content and lower excised leaf water loss had better adaptation to water stress.

Multiple testing and power calculations in genetic association studies.

PubMed

So, Hon-Cheong; Sham, Pak C

2011-01-01

Modern genetic association studies typically involve multiple single-nucleotide polymorphisms (SNPs) and/or multiple genes. With the development of high-throughput genotyping technologies and the reduction in genotyping cost, investigators can now assay up to a million SNPs for direct or indirect association with disease phenotypes. In addition, some studies involve multiple disease or related phenotypes and use multiple methods of statistical analysis. The combination of multiple genetic loci, multiple phenotypes, and multiple methods of evaluating associations between genotype and phenotype means that modern genetic studies often involve the testing of an enormous number of hypotheses. When multiple hypothesis tests are performed in a study, there is a risk of inflation of the type I error rate (i.e., the chance of falsely claiming an association when there is none). Several methods for multiple-testing correction are in popular use, and they all have strengths and weaknesses. Because no single method is universally adopted or always appropriate, it is important to understand the principles, strengths, and weaknesses of the methods so that they can be applied appropriately in practice. In this article, we review the three principle methods for multiple-testing correction and provide guidance for calculating statistical power.

Genetic analyses, phenotypic adaptability and stability in sugarcane genotypes for commercial cultivation in Pernambuco.

PubMed

Dutra Filho, J A; Junior, T C; Simões Neto, D E

2015-10-05

In the present study, we assessed the agro-industrial performance of 22 sugarcane genotypes adaptable to edaphoclimatic conditions in production microregions in the State of Pernambuco, Brazil, and we recommended the commercial cultivation of select genotypes. The variables analyzed were as follows: sucrose percentage in cane juice, tonnage of saccharose per hectare (TPH), sugarcane tonnage per hectare (TCH), fiber, solid soluble contents, total recoverable sugar tonnage (ATR), and total recoverable sugar tonnage per hectare (ATR t/ha). A randomized block design with 4 repeats was used. Combined variance of the experiments, genetic parameter estimates, and environment stratification were analyzed. Phenotypic adaptability and stability were analyzed using the Annicchiarico and Wricke methods and analysis of variance. Genetic gain was estimated using the classic index and sum of ranks. Genotype selection was efficient for TPH, TCH, and ATR t/ha. Genotypes presented a great potential for improvement and a similar response pattern in Litoral Norte and Mata Sul microregions for TPH and TCH and Litoral Norte and Litoral Sul microregions for ATR t/ha. Genotypes SP78-4764, RB813804, and SP79-101 showed better productivity and phenotypic adaptability and stability, according to the Wricke and Annicchiarico methods. These genotypes can be recommended for cultivation in the sugarcane belt in the State of Pernambuco.

Accounting for Genotype-by-Environment Interactions and Residual Genetic Variation in Genomic Selection for Water-Soluble Carbohydrate Concentration in Wheat.

PubMed

Ovenden, Ben; Milgate, Andrew; Wade, Len J; Rebetzke, Greg J; Holland, James B

2018-05-31

Abiotic stress tolerance traits are often complex and recalcitrant targets for conventional breeding improvement in many crop species. This study evaluated the potential of genomic selection to predict water-soluble carbohydrate concentration (WSCC), an important drought tolerance trait, in wheat under field conditions. A panel of 358 varieties and breeding lines constrained for maturity was evaluated under rainfed and irrigated treatments across two locations and two years. Whole-genome marker profiles and factor analytic mixed models were used to generate genomic estimated breeding values (GEBVs) for specific environments and environment groups. Additive genetic variance was smaller than residual genetic variance for WSCC, such that genotypic values were dominated by residual genetic effects rather than additive breeding values. As a result, GEBVs were not accurate predictors of genotypic values of the extant lines, but GEBVs should be reliable selection criteria to choose parents for intermating to produce new populations. The accuracy of GEBVs for untested lines was sufficient to increase predicted genetic gain from genomic selection per unit time compared to phenotypic selection if the breeding cycle is reduced by half by the use of GEBVs in off-season generations. Further, genomic prediction accuracy depended on having phenotypic data from environments with strong correlations with target production environments to build prediction models. By combining high-density marker genotypes, stress-managed field evaluations, and mixed models that model simultaneously covariances among genotypes and covariances of complex trait performance between pairs of environments, we were able to train models with good accuracy to facilitate genetic gain from genomic selection. Copyright © 2018 Ovenden et al.

In silico analysis of a disease-causing mutation in PCDH15 gene in a consanguineous Pakistani family with Usher phenotype.

PubMed

Saleha, Shamim; Ajmal, Muhammad; Jamil, Muhammad; Nasir, Muhammad; Hameed, Abdul

2016-01-01

To map Usher phenotype in a consanguineous Pakistani family and identify disease-associated mutation in a causative gene to establish phenotype-genotype correlation. A consanguineous Pakistani family in which Usher phenotype was segregating as an autosomal recessive trait was ascertained. On the basis of results of clinical investigations of affected members of this family disease was diagnosed as Usher syndrome (USH). To identify the locus responsible for the Usher phenotype in this family, genomic DNA from blood sample of each individual was genotyped using microsatellite Short Tandem Repeat (STR) markers for the known Usher syndrome loci. Then direct sequencing was performed to find out disease associated mutations in the candidate gene. By genetic linkage analysis, the USH phenotype of this family was mapped to PCDH15 locus on chromosome 10q21.1. Three different point mutations in exon 11 of PCDH15 were identified and one of them, c.1304A>C was found to be segregating with the disease phenotype in Pakistani family with Usher phenotype. This, c.1304A>C transversion mutation predicts an amino-acid substitution of aspartic acid with an alanine at residue number 435 (p.D435A) of its protein product. Moreover, in silico analysis revealed conservation of aspartic acid at position 435 and predicated this change as pathogenic. The identification of c.1304A>C pathogenic mutation in PCDH15 gene and its association with Usher syndrome in a consanguineous Pakistani family is the first example of a missense mutation of PCDH15 causing USH1 phenotype. In previous reports, it was hypothesized that severe mutations such as truncated protein of PCDH15 led to the Usher I phenotype and that missense variants are mainly responsible for non-syndromic hearing impairment.

Correlation between phenotypic antibiotic susceptibility and the resistome in Pseudomonas aeruginosa.

PubMed

Jaillard, Magali; van Belkum, Alex; Cady, Kyle C; Creely, David; Shortridge, Dee; Blanc, Bernadette; Barbu, E Magda; Dunne, W Michael; Zambardi, Gilles; Enright, Mark; Mugnier, Nathalie; Le Priol, Christophe; Schicklin, Stéphane; Guigon, Ghislaine; Veyrieras, Jean-Baptiste

2017-08-01

Genetic determinants of antibiotic resistance (AR) have been extensively investigated. High-throughput sequencing allows for the assessment of the relationship between genotype and phenotype. A panel of 672 Pseudomonas aeruginosa strains was analysed, including representatives of globally disseminated multidrug-resistant and extensively drug-resistant clones; genomes and multiple antibiograms were available. This panel was annotated for AR gene presence and polymorphism, defining a resistome in which integrons were included. Integrons were present in >70 distinct cassettes, with In5 being the most prevalent. Some cassettes closely associated with clonal complexes, whereas others spread across the phylogenetic diversity, highlighting the importance of horizontal transfer. A resistome-wide association study (RWAS) was performed for clinically relevant antibiotics by correlating the variability in minimum inhibitory concentration (MIC) values with resistome data. Resistome annotation identified 147 loci associated with AR. These loci consisted mainly of acquired genomic elements and intrinsic genes. The RWAS allowed for correct identification of resistance mechanisms for meropenem, amikacin, levofloxacin and cefepime, and added 46 novel mutations. Among these, 29 were variants of the oprD gene associated with variation in meropenem MIC. Using genomic and MIC data, phenotypic AR was successfully correlated with molecular determinants at the whole-genome sequence level. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Genotyping of Mycobacterium intracellulare isolates and clinical characteristics of lung disease.

PubMed

Kim, S-Y; Lee, S-T; Jeong, B-H; Park, H Y; Jeon, K; Kim, J-W; Shin, S J; Koh, W-J

2013-05-01

Variable number of tandem repeats (VNTR) loci were recently identified in Japanese isolates of Mycobacterium intracellulare. We hypothesised that some mycobacterial genotypes are more virulent than others, resulting in particular genotypes being associated with disease phenotype and progression. To evaluate the VNTR loci of M. intracellulare in clinical isolates from Korean patients, and investigate the association between mycobacterial genotype and disease phenotype and progression. In total, 70 M. intracellulare clinical isolates were genotyped using 16 M. intracellulare VNTR loci. VNTR typing showed strong discriminatory power and genetic diversity for molecular epidemiological studies of M. intracellulare. In a phylogenetic tree, the M. intracellulare clinical isolates were divided into two clusters (A and B). Cluster A was observed more frequently (77%) than Cluster B; however, there was no association between the clinical characteristics, disease progression, drug susceptibility and clusters based on VNTR genotyping. VNTR typing could be used for epidemiological studies of M. intracellulare lung disease; however, no association was found between the specific VNTR genotypes of M. intracellulare and the clinical characteristics of Korean patients.

Factor VII Deficiency: Clinical Phenotype, Genotype and Therapy.

PubMed

Napolitano, Mariasanta; Siragusa, Sergio; Mariani, Guglielmo

2017-03-28

Factor VII deficiency is the most common among rare inherited autosomal recessive bleeding disorders, and is a chameleon disease due to the lack of a direct correlation between plasma levels of coagulation Factor VII and bleeding manifestations. Clinical phenotypes range from asymptomatic condition-even in homozygous subjects-to severe life-threatening bleedings (central nervous system, gastrointestinal bleeding). Prediction of bleeding risk is thus based on multiple parameters that challenge disease management. Spontaneous or surgical bleedings require accurate treatment schedules, and patients at high risk of severe hemorrhages may need prophylaxis from childhood onwards. The aim of the current review is to depict an updated summary of clinical phenotype, laboratory diagnosis, and treatment of inherited Factor VII deficiency.

Factor VII Deficiency: Clinical Phenotype, Genotype and Therapy

PubMed Central

Napolitano, Mariasanta; Siragusa, Sergio; Mariani, Guglielmo

2017-01-01

Factor VII deficiency is the most common among rare inherited autosomal recessive bleeding disorders, and is a chameleon disease due to the lack of a direct correlation between plasma levels of coagulation Factor VII and bleeding manifestations. Clinical phenotypes range from asymptomatic condition—even in homozygous subjects—to severe life-threatening bleedings (central nervous system, gastrointestinal bleeding). Prediction of bleeding risk is thus based on multiple parameters that challenge disease management. Spontaneous or surgical bleedings require accurate treatment schedules, and patients at high risk of severe hemorrhages may need prophylaxis from childhood onwards. The aim of the current review is to depict an updated summary of clinical phenotype, laboratory diagnosis, and treatment of inherited Factor VII deficiency. PMID:28350321

Phenotype variations affect genetic association studies of degenerative disc disease: conclusions of analysis of genetic association of 58 single nucleotide polymorphisms with highly specific phenotypes for disc degeneration in 332 subjects.

PubMed

Rajasekaran, S; Kanna, Rishi Mugesh; Senthil, Natesan; Raveendran, Muthuraja; Cheung, Kenneth M C; Chan, Danny; Subramaniam, Sakthikanal; Shetty, Ajoy Prasad

2013-10-01

Although the influence of genetics on the process of disc degeneration is well recognized, in recently published studies, there is a wide variation in the race and selection criteria for such study populations. More importantly, the radiographic features of disc degeneration that are selected to represent the disc degeneration phenotype are variable in these studies. The study presented here evaluates the association between single nucleotide polymorphisms (SNPs) of candidate genes and three distinct radiographic features that can be defined as the degenerative disc disease (DDD) phenotype. The study objectives were to examine the allelic diversity of 58 SNPs related to 35 candidate genes related to lumbar DDD, to evaluate the association in a hitherto unevaluated ethnic Indian population that represents more than one-sixth of the world population, and to analyze how genetic associations can vary in the same study subjects with the choice of phenotype. A cross-sectional, case-control study of an ethnic Indian population was carried out. Fifty-eight SNPs in 35 potential candidate genes were evaluated in 342 subjects and the associations were analyzed against three highly specific markers for DDD, namely disc degeneration by Pfirrmann grading, end-plate damage evaluated by total end-plate damage score, and annular tears evaluated by disc herniations and hyperintense zones. Genotyping of cases and controls was performed on a genome-wide SNP array to identify potential associated disease loci. The results from the genome-wide SNP array were then used to facilitate SNP selection and genotype validation was conducted using Sequenom-based genotyping. Eleven of the 58 SNPs provided evidence of association with one of the phenotypes. For annular tears, rs1042631 SNP of AGC1 and rs467691 SNP of ADAMTS5 were highly significantly associated (p<.01) and SNPs in NGFB, IL1B, IL18RAP, and MMP10 were also significantly associated (p<.05). The rs4076018 SNP of NGFB was highly significant (p<.01) and rs2292657 SNP of GLI1 was significantly (p<.05) correlated to disc degeneration. For end-plate damage, the rs2252070 SNP of MMP 13 showed a significant association (p<.05). Previously associated genes such as COL 9, SKT, CHST 3, CILP, IGFR, SOXp, BMP, MMP 2-12, ADH2, IL1RN, and COX2 were not significantly associated and new associations (NGFB and GLI1) were identified. The validity of all the associations was found to be phenotype dependent. For the first time, genetic associations with DDD have been performed in an Indian population. Apart from identifying new associations, the highlight of the study was that in the same study population with DDD, SNP associations completely changed when different radiographic features were used to define the DDD phenotype. Our study results therefore indicate that standardization of the phenotypes chosen to study the genetics of disc degeneration is essential and should be strongly considered before planning genetic association studies. Copyright © 2013 Elsevier Inc. All rights reserved.

A challenge to the striking genotypic heterogeneity of retinitis pigmentosa: a better understanding of the pathophysiology using the newest genetic strategies

PubMed Central

Sorrentino, F S; Gallenga, C E; Bonifazzi, C; Perri, P

2016-01-01

Retinitis pigmentosa (RP) is a group of inherited retinal disorders characterized by a complex association between tremendous genotypic multiplicity and great phenotypic heterogeneity. The severity of the clinical manifestation depends on penetrance and expressivity of the disease-gene. Also, various interactions between gene expression and environmental factors have been hypothesized. More than 250 genes with ~4500 causative mutations have been reported to be involved in different RP-related mechanisms. Nowadays, not more than the 50% of RPs are attributable to identified genes, whereas the rest of molecular defects are still undetectable, especially in populations where few genetic screenings have been performed. Therefore, new genetic strategies can be a remarkably useful tool to aid clinical diagnosis, potentially modifying treatment options, and family counseling. Genome-wide analytical techniques (array comparative genomic hybridization and single-nucleotide polymorphism genotyping) and DNA sequencing strategies (arrayed primer extension, Sanger sequencing, and ultra high-throughput sequencing) are successfully used to early make molecular diagnosis detecting single or multiple mutations in the huge heterogeneity of RPs. To date, further research needs to be carried out to better investigate the genotype/phenotype correlation, putting together genetic and clinical findings to provide detailed information concerning the risk of RP development and novel effective treatments. PMID:27564722

Revealing the Diversity of Introduced Coffea canephora Germplasm in Ecuador: Towards a National Strategy to Improve Robusta.

PubMed

Loor Solórzano, Rey Gastón; De Bellis, Fabien; Leroy, Thierry; Plaza, Luis; Guerrero, Hilton; Subia, Cristian; Calderón, Darío; Fernández, Fabián; Garzón, Iván; Lopez, Diana; Vera, Danilo

2017-01-01

Genetic resources of Coffea canephora have been introduced in several tropical countries with potential for crop development. In Ecuador, the species has been cultivated since the mid-20th century. However, little is known about the diversity and genetic structure of introduced germplasm. This paper provides an overview of the genetic and phenotypic diversity of C. canephora in Ecuador and some proposals for implementing a breeding program. Twelve SSR markers were used to analyze 1491 plants of C. canephora grown in different living collections in Ecuador, compared to 29 genotypes representing the main genetic and geographic diversity groups identified within the species. Results indicated that most of the genotypes introduced are of Congolese origin, with accessions from both main subgroups, SG1 and SG2. Some genotypes were classed as hybrids between both subgroups. Substantial phenotypic diversity was also found, and correlations were observed with genetic diversity. Ecuadorian Robusta coffee displays wide genetic diversity and we propose some ways of improving Robusta in Ecuador. A breeding program could be based on three operations: the choice of elite clones, the introduction of new material from other countries (Ivory Coast, Uganda), and the creation of new hybrid material using genotypes from the different diversity groups.

Revealing the Diversity of Introduced Coffea canephora Germplasm in Ecuador: Towards a National Strategy to Improve Robusta

PubMed Central

De Bellis, Fabien; Leroy, Thierry; Plaza, Luis; Guerrero, Hilton; Subia, Cristian; Calderón, Darío; Fernández, Fabián; Garzón, Iván; Lopez, Diana; Vera, Danilo

2017-01-01

Genetic resources of Coffea canephora have been introduced in several tropical countries with potential for crop development. In Ecuador, the species has been cultivated since the mid-20th century. However, little is known about the diversity and genetic structure of introduced germplasm. This paper provides an overview of the genetic and phenotypic diversity of C. canephora in Ecuador and some proposals for implementing a breeding program. Twelve SSR markers were used to analyze 1491 plants of C. canephora grown in different living collections in Ecuador, compared to 29 genotypes representing the main genetic and geographic diversity groups identified within the species. Results indicated that most of the genotypes introduced are of Congolese origin, with accessions from both main subgroups, SG1 and SG2. Some genotypes were classed as hybrids between both subgroups. Substantial phenotypic diversity was also found, and correlations were observed with genetic diversity. Ecuadorian Robusta coffee displays wide genetic diversity and we propose some ways of improving Robusta in Ecuador. A breeding program could be based on three operations: the choice of elite clones, the introduction of new material from other countries (Ivory Coast, Uganda), and the creation of new hybrid material using genotypes from the different diversity groups. PMID:29214204

ABO Blood Type and Personality Traits in Healthy Japanese Subjects.

PubMed

Tsuchimine, Shoko; Saruwatari, Junji; Kaneda, Ayako; Yasui-Furukori, Norio

2015-01-01

There is no scientific consensus that a relationship exists between the ABO blood group and personality traits. However, a recent study hypothesized that the dopamine beta-hydroxylase (DBH) gene is in linkage with the ABO gene. The sample population consisted of 1,427 healthy Japanese subjects who completed the Temperament and Character Inventory (TCI). Each subject's ABO blood type was determined by genotyping the rs8176719 and rs8176746 ABO gene single-nucleotide polymorphisms (SNPs) using a TaqMan genotyping assay. The relationships between the six ABO genotypes or four ABO phenotypes and personality traits were examined using a multivariate analysis of covariance (MANCOVA), controlling for age and sex. The MANCOVA data showed a significant difference in TCI scores among the ABO genotype groups (F [7, 1393] = 3.354, p = 0.001). A subsequent univariate analysis showed a significant difference in the mean scores for Persistence among the genotype groups (F = 2.680, partial η2 = 0.010, p = 0.020). Similarly, dividing the ABO blood type into four phenotypes revealed a significant difference among the phenotype groups (F [7, 1397] = 2.529, p = 0.014). A subsequent univariate analysis showed a significant difference among the phenotype groups in the mean scores for Persistence (F = 2.952, partial η2= 0.006, p = 0.032). We observed a significant association between ABO blood group genotypes and personality traits in a large number of healthy Japanese subjects. However, these results should be regarded as preliminary and should be interpreted with caution because it is possible that the association between ABO blood group genotype and the Persistence trait is relatively weak.

Adaptive phenotypic plasticity and local adaptation for temperature tolerance in freshwater zooplankton

PubMed Central

Yampolsky, Lev Y.; Schaer, Tobias M. M.; Ebert, Dieter

2014-01-01

Many organisms have geographical distributions extending from the tropics to near polar regions or can experience up to 30°C temperature variation within the lifespan of an individual. Two forms of evolutionary adaptation to such wide ranges in ambient temperatures are frequently discussed: local adaptation and phenotypic plasticity. The freshwater planktonic crustacean Daphnia magna, whose range extends from South Africa to near arctic sites, shows strong phenotypic and genotypic variation in response to temperature. In this study, we use D. magna clones from 22 populations (one clone per population) ranging from latitude 0° (Kenya) to 66° North (White Sea) to explore the contributions of phenotypic plasticity and local adaptation to high temperature tolerance. Temperature tolerance was studied as knockout time (time until immobilization, Timm) at 37°C in clones acclimatized to either 20°C or 28°C. Acclimatization to 28°C strongly increased Timm, testifying to adaptive phenotypic plasticity. At the same time, Timm significantly correlated with average high temperature at the clones’ sites of origin, suggesting local adaptation. As earlier studies have found that haemoglobin expression contributes to temperature tolerance, we also quantified haemoglobin concentration in experimental animals and found that both acclimatization temperature (AccT) and temperature at the site of origin are positively correlated with haemoglobin concentration. Furthermore, Daphnia from warmer climates upregulate haemoglobin much more strongly in response to AccT, suggesting local adaptation for plasticity in haemoglobin expression. Our results show that both local adaptation and phenotypic plasticity contribute to temperature tolerance, and elucidate a possible role of haemoglobin in mediating these effects that differs along a cold–warm gradient. PMID:24352948

‘Particle genetics’: treating every cell as unique

PubMed Central

Yvert, Gaël

2014-01-01

Genotype-phenotype relations are usually inferred from a deterministic point of view. For example, quantitative trait loci (QTL), which describe regions of the genome associated with a particular phenotype, are based on a mean trait difference between genotype categories. However, living systems comprise huge numbers of cells (the ‘particles’ of biology). Each cell can exhibit substantial phenotypic individuality, which can have dramatic consequences at the organismal level. Now, with technology capable of interrogating individual cells, it is time to consider how genotypes shape the probability laws of single cell traits. The possibility of mapping single cell probabilistic trait loci (PTL), which link genomic regions to probabilities of cellular traits, is a promising step in this direction. This approach requires thinking about phenotypes in probabilistic terms, a concept that statistical physicists have been applying to particles for a century. Here, I describe PTL and discuss their potential to enlarge our understanding of genotype-phenotype relations. PMID:24315431

eCOMPAGT integrates mtDNA: import, validation and export of mitochondrial DNA profiles for population genetics, tumour dynamics and genotype-phenotype association studies.

PubMed

Weissensteiner, Hansi; Schönherr, Sebastian; Specht, Günther; Kronenberg, Florian; Brandstätter, Anita

2010-03-09

Mitochondrial DNA (mtDNA) is widely being used for population genetics, forensic DNA fingerprinting and clinical disease association studies. The recent past has uncovered severe problems with mtDNA genotyping, not only due to the genotyping method itself, but mainly to the post-lab transcription, storage and report of mtDNA genotypes. eCOMPAGT, a system to store, administer and connect phenotype data to all kinds of genotype data is now enhanced by the possibility of storing mtDNA profiles and allowing their validation, linking to phenotypes and export as numerous formats. mtDNA profiles can be imported from different sequence evaluation programs, compared between evaluations and their haplogroup affiliations stored. Furthermore, eCOMPAGT has been improved in its sophisticated transparency (support of MySQL and Oracle), security aspects (by using database technology) and the option to import, manage and store genotypes derived from various genotyping methods (SNPlex, TaqMan, and STRs). It is a software solution designed for project management, laboratory work and the evaluation process all-in-one. The extended mtDNA version of eCOMPAGT was designed to enable error-free post-laboratory data handling of human mtDNA profiles. This software is suited for small to medium-sized human genetic, forensic and clinical genetic laboratories. The direct support of MySQL and the improved database security options render eCOMPAGT a powerful tool to build an automated workflow architecture for several genotyping methods. eCOMPAGT is freely available at http://dbis-informatik.uibk.ac.at/ecompagt.

eCOMPAGT integrates mtDNA: import, validation and export of mitochondrial DNA profiles for population genetics, tumour dynamics and genotype-phenotype association studies

PubMed Central

2010-01-01

Background Mitochondrial DNA (mtDNA) is widely being used for population genetics, forensic DNA fingerprinting and clinical disease association studies. The recent past has uncovered severe problems with mtDNA genotyping, not only due to the genotyping method itself, but mainly to the post-lab transcription, storage and report of mtDNA genotypes. Description eCOMPAGT, a system to store, administer and connect phenotype data to all kinds of genotype data is now enhanced by the possibility of storing mtDNA profiles and allowing their validation, linking to phenotypes and export as numerous formats. mtDNA profiles can be imported from different sequence evaluation programs, compared between evaluations and their haplogroup affiliations stored. Furthermore, eCOMPAGT has been improved in its sophisticated transparency (support of MySQL and Oracle), security aspects (by using database technology) and the option to import, manage and store genotypes derived from various genotyping methods (SNPlex, TaqMan, and STRs). It is a software solution designed for project management, laboratory work and the evaluation process all-in-one. Conclusions The extended mtDNA version of eCOMPAGT was designed to enable error-free post-laboratory data handling of human mtDNA profiles. This software is suited for small to medium-sized human genetic, forensic and clinical genetic laboratories. The direct support of MySQL and the improved database security options render eCOMPAGT a powerful tool to build an automated workflow architecture for several genotyping methods. eCOMPAGT is freely available at http://dbis-informatik.uibk.ac.at/ecompagt. PMID:20214782

From genotype to phenotype: genetics and medical practice in the new millennium.

PubMed Central

Weatherall, D

1999-01-01

The completion of the human genome project will provide a vast amount of information about human genetic diversity. One of the major challenges for the medical sciences will be to relate genotype to phenotype. Over recent years considerable progress has been made in relating the molecular pathology of monogenic diseases to the associated clinical phenotypes. Studies of the inherited disorders of haemoglobin, notably the thalassaemias, have shown how even in these, the simplest of monogenic diseases, there is remarkable complexity with respect to their phenotypic expression. Although studies of other monogenic diseases are less far advanced, it is clear that the same level of complexity will exist. This information provides some indication of the difficulties that will be met when trying to define the genes that are involved in common multigenic disorders and, in particular, in trying to relate disease phenotypes to the complex interactions between many genes and multiple environmental factors. PMID:10670020

Genomewide Association Studies for 50 Agronomic Traits in Peanut Using the ‘Reference Set’ Comprising 300 Genotypes from 48 Countries of the Semi-Arid Tropics of the World

PubMed Central

Pandey, Manish K.; Upadhyaya, Hari D.; Rathore, Abhishek; Vadez, Vincent; Sheshshayee, M. S.; Sriswathi, Manda; Govil, Mansee; Kumar, Ashish; Gowda, M. V. C.; Sharma, Shivali; Hamidou, Falalou; Kumar, V. Anil; Khera, Pawan; Bhat, Ramesh S.; Khan, Aamir W.; Singh, Sube; Li, Hongjie; Monyo, Emmanuel; Nadaf, H. L.; Mukri, Ganapati; Jackson, Scott A.; Guo, Baozhu; Liang, Xuanqiang; Varshney, Rajeev K.

2014-01-01

Peanut is an important and nutritious agricultural commodity and a livelihood of many small-holder farmers in the semi-arid tropics (SAT) of world which are facing serious production threats. Integration of genomics tools with on-going genetic improvement approaches is expected to facilitate accelerated development of improved cultivars. Therefore, high-resolution genotyping and multiple season phenotyping data for 50 important agronomic, disease and quality traits were generated on the ‘reference set’ of peanut. This study reports comprehensive analyses of allelic diversity, population structure, linkage disequilibrium (LD) decay and marker-trait association (MTA) in peanut. Distinctness of all the genotypes can be established by using either an unique allele detected by a single SSR or a combination of unique alleles by two or more than two SSR markers. As expected, DArT features (2.0 alleles/locus, 0.125 PIC) showed lower allele frequency and polymorphic information content (PIC) than SSRs (22.21 alleles /locus, 0.715 PIC). Both marker types clearly differentiated the genotypes of diploids from tetraploids. Multi-allelic SSRs identified three sub-groups (K = 3) while the LD simulation trend line based on squared-allele frequency correlations (r2) predicted LD decay of 15–20 cM in peanut genome. Detailed analysis identified a total of 524 highly significant MTAs (pvalue >2.1×10–6) with wide phenotypic variance (PV) range (5.81–90.09%) for 36 traits. These MTAs after validation may be deployed in improving biotic resistance, oil/ seed/ nutritional quality, drought tolerance related traits, and yield/ yield components. PMID:25140620

F7 gene variants modulate protein levels in a large cohort of patients with factor VII deficiency. Results from a genotype-phenotype study.

PubMed

Quintavalle, Gabriele; Riccardi, Federica; Rivolta, Gianna Franca; Martorana, Davide; Di Perna, Caterina; Percesepe, Antonio; Tagliaferri, Annarita

2017-08-01

Congenital factor VII (FVII) deficiency is a rare bleeding disorder caused by mutations in F7 gene with autosomal recessive inheritance. A clinical heterogeneity with poor correlation with FVII:C levels has been described. It was the objective of this study to identify genetic defects and to evaluate their relationships with phenotype in a large cohort of patients with FVII:C<50 %. One hundred twenty-three probands were genotyped for F7 mutations and three polymorphic variants and classified according to recently published clinical scores. Forty out of 123 patients (33 %) were symptomatic (43 bleedings). A severe bleeding tendency was observed only in patients with FVII:C<0.10 %. Epistaxis (11 %) and menorrhagia (32 % of females in fertile age) were the most frequent bleedings. Molecular analysis detected 48 mutations, 20 not reported in the F7 international databases. Most mutations (62 %) were missense, large deletions were 6.2 %. Compound heterozygotes/homozygotes for mutations presented lower FVII:C levels compared to the other classes (Chi 2 =43.709, p<0,001). The polymorphisms distribution was significantly different among the three F7 genotypic groups (Chi 2 =72.289, p<0,001). The presence of truncating mutations was associated with lowest FVII:C levels (Chi 2 =21.351, p=0.002). This study confirms the clinical and molecular variability of the disease and the type of symptoms. It shows a good correlation between the type of F7 mutation and/or polymorphisms and FVII:C levels, without a direct link between FVII:C and bleeding tendency. The results suggest that large deletions are underestimated and that they represent a common mechanism of F7 gene inactivation which should always be investigated in the diagnostic testing for FVII deficiency.

High-throughput phenotyping of large wheat breeding nurseries using unmanned aerial system, remote sensing and GIS techniques

NASA Astrophysics Data System (ADS)

Haghighattalab, Atena

Wheat breeders are in a race for genetic gain to secure the future nutritional needs of a growing population. Multiple barriers exist in the acceleration of crop improvement. Emerging technologies are reducing these obstacles. Advances in genotyping technologies have significantly decreased the cost of characterizing the genetic make-up of candidate breeding lines. However, this is just part of the equation. Field-based phenotyping informs a breeder's decision as to which lines move forward in the breeding cycle. This has long been the most expensive and time-consuming, though most critical, aspect of breeding. The grand challenge remains in connecting genetic variants to observed phenotypes followed by predicting phenotypes based on the genetic composition of lines or cultivars. In this context, the current study was undertaken to investigate the utility of UAS in assessment field trials in wheat breeding programs. The major objective was to integrate remotely sensed data with geospatial analysis for high throughput phenotyping of large wheat breeding nurseries. The initial step was to develop and validate a semi-automated high-throughput phenotyping pipeline using a low-cost UAS and NIR camera, image processing, and radiometric calibration to build orthomosaic imagery and 3D models. The relationship between plot-level data (vegetation indices and height) extracted from UAS imagery and manual measurements were examined and found to have a high correlation. Data derived from UAS imagery performed as well as manual measurements while exponentially increasing the amount of data available. The high-resolution, high-temporal HTP data extracted from this pipeline offered the opportunity to develop a within season grain yield prediction model. Due to the variety in genotypes and environmental conditions, breeding trials are inherently spatial in nature and vary non-randomly across the field. This makes geographically weighted regression models a good choice as a geospatial prediction model. Finally, with the addition of georeferenced and spatial data integral in HTP and imagery, we were able to reduce the environmental effect from the data and increase the accuracy of UAS plot-level data. The models developed through this research, when combined with genotyping technologies, increase the volume, accuracy, and reliability of phenotypic data to better inform breeder selections. This increased accuracy with evaluating and predicting grain yield will help breeders to rapidly identify and advance the most promising candidate wheat varieties.

The super sickling haemoglobin HbS-Oman: a study of red cell sickling, K+ permeability and associations with disease severity in patients heterozygous for HbA and HbS-Oman (HbA/S-Oman genotype).

PubMed

Al Balushi, Halima W M; Wali, Yasser; Al Awadi, Maha; Al-Subhi, Taimoora; Rees, David C; Brewin, John N; Hannemann, Anke; Gibson, John S

2017-10-01

Studying different sickle cell genotypes may throw light on the pathogenesis of sickle cell disease (SCD). Here, the clinical profile, red cell sickling and K + permeability in 29 SCD patients (15 patients with severe disease and 14 with a milder form) of HbA/S-Oman genotype were analysed. The super sickling nature of this Hb variant was confirmed. The red cell membrane permeability to K + was markedly abnormal with elevated activities of P sickle , Gardos channel and KCl cotransporter (KCC). Results were consistent with Ca 2+ entry and Mg 2+ loss via P sickle stimulating Gardos channel and KCC activities. The abnormal red cell behaviour was similar to that in the commonest genotype of SCD, HbSS, in which the level of mutated Hb is considerably higher. Although activities of all three K + transporters also correlated with the level of HbS-Oman, there was no association between transport phenotype and disease severity. The super sickling behaviour of HbS-Oman may obviate the need for solute loss and red cell dehydration to encourage Hb polymerisation, required in other SCD genotypes. Disease severity was reduced by concurrent α thalassaemia, as observed in other SCD genotypes, and represents an obvious genetic marker for prognostic tests of severity in young SCD patients of the HbA/S-Oman genotype. © 2017 John Wiley & Sons Ltd.

Genonets server-a web server for the construction, analysis and visualization of genotype networks.

PubMed

Khalid, Fahad; Aguilar-Rodríguez, José; Wagner, Andreas; Payne, Joshua L

2016-07-08

A genotype network is a graph in which vertices represent genotypes that have the same phenotype. Edges connect vertices if their corresponding genotypes differ in a single small mutation. Genotype networks are used to study the organization of genotype spaces. They have shed light on the relationship between robustness and evolvability in biological systems as different as RNA macromolecules and transcriptional regulatory circuits. Despite the importance of genotype networks, no tool exists for their automatic construction, analysis and visualization. Here we fill this gap by presenting the Genonets Server, a tool that provides the following features: (i) the construction of genotype networks for categorical and univariate phenotypes from DNA, RNA, amino acid or binary sequences; (ii) analyses of genotype network topology and how it relates to robustness and evolvability, as well as analyses of genotype network topography and how it relates to the navigability of a genotype network via mutation and natural selection; (iii) multiple interactive visualizations that facilitate exploratory research and education. The Genonets Server is freely available at http://ieu-genonets.uzh.ch. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Multiple endocrine neoplasia type 1: analysis of germline MEN1 mutations in the Italian multicenter MEN1 patient database.

PubMed

Marini, Francesca; Giusti, Francesca; Fossi, Caterina; Cioppi, Federica; Cianferotti, Luisella; Masi, Laura; Boaretto, Francesca; Zovato, Stefania; Cetani, Filomena; Colao, Annamaria; Davì, Maria Vittoria; Faggiano, Antongiulio; Fanciulli, Giuseppe; Ferolla, Piero; Ferone, Diego; Loli, Paola; Mantero, Franco; Marcocci, Claudio; Opocher, Giuseppe; Beck-Peccoz, Paolo; Persani, Luca; Scillitani, Alfredo; Guizzardi, Fabiana; Spada, Anna; Tomassetti, Paola; Tonelli, Francesco; Brandi, Maria Luisa

2018-03-01

Multiple endocrine neoplasia type 1 (MEN1) is caused by germline inactivating mutations of the MEN1 gene. Currently, no direct genotype-phenotype correlation is identified. We aim to analyze MEN1 mutation site and features, and possible correlations between the mutation type and/or the affected menin functional domain and clinical presentation in patients from the Italian multicenter MEN1 database, one of the largest worldwide MEN1 mutation series published to date. The study included the analysis of MEN1 mutation profile in 410 MEN1 patients [370 familial cases from 123 different pedigrees (48 still asymptomatic at the time of this study) and 40 single cases]. We identified 99 different mutations: 41 frameshift [small intra-exon deletions (28) or insertions (13)], 13 nonsense, 26 missense and 11 splicing site mutations, 4 in-frame small deletions, and 4 intragenic large deletions spanning more than one exon. One family had two different inactivating MEN1 mutations on the same allele. Gastro-entero-pancreatic tumors resulted more frequent in patients with a nonsense mutation, and thoracic neuroendocrine tumors in individuals bearing a splicing-site mutation. Our data regarding mutation type frequency and distribution are in accordance with previously published data: MEN1 mutations are scattered through the entire coding region, and truncating mutations are the most common in MEN1 syndrome. A specific direct correlation between MEN1 genotype and clinical phenotype was not found in all our families, and wide intra-familial clinical variability and variable disease penetrance were both confirmed, suggesting a role for modifying, still undetermined, factors, explaining the variable MEN1 tumorigenesis.

Evaluation of Genome-Enabled Selection for Bacterial Cold Water Disease Resistance Using Progeny Performance Data in Rainbow Trout: Insights on Genotyping Methods and Genomic Prediction Models.

PubMed

Vallejo, Roger L; Leeds, Timothy D; Fragomeni, Breno O; Gao, Guangtu; Hernandez, Alvaro G; Misztal, Ignacy; Welch, Timothy J; Wiens, Gregory D; Palti, Yniv

2016-01-01

Bacterial cold water disease (BCWD) causes significant economic losses in salmonid aquaculture, and traditional family-based breeding programs aimed at improving BCWD resistance have been limited to exploiting only between-family variation. We used genomic selection (GS) models to predict genomic breeding values (GEBVs) for BCWD resistance in 10 families from the first generation of the NCCCWA BCWD resistance breeding line, compared the predictive ability (PA) of GEBVs to pedigree-based estimated breeding values (EBVs), and compared the impact of two SNP genotyping methods on the accuracy of GEBV predictions. The BCWD phenotypes survival days (DAYS) and survival status (STATUS) had been recorded in training fish (n = 583) subjected to experimental BCWD challenge. Training fish, and their full sibs without phenotypic data that were used as parents of the subsequent generation, were genotyped using two methods: restriction-site associated DNA (RAD) sequencing and the Rainbow Trout Axiom® 57 K SNP array (Chip). Animal-specific GEBVs were estimated using four GS models: BayesB, BayesC, single-step GBLUP (ssGBLUP), and weighted ssGBLUP (wssGBLUP). Family-specific EBVs were estimated using pedigree and phenotype data in the training fish only. The PA of EBVs and GEBVs was assessed by correlating mean progeny phenotype (MPP) with mid-parent EBV (family-specific) or GEBV (animal-specific). The best GEBV predictions were similar to EBV with PA values of 0.49 and 0.46 vs. 0.50 and 0.41 for DAYS and STATUS, respectively. Among the GEBV prediction methods, ssGBLUP consistently had the highest PA. The RAD genotyping platform had GEBVs with similar PA to those of GEBVs from the Chip platform. The PA of ssGBLUP and wssGBLUP methods was higher with the Chip, but for BayesB and BayesC methods it was higher with the RAD platform. The overall GEBV accuracy in this study was low to moderate, likely due to the small training sample used. This study explored the potential of GS for improving resistance to BCWD in rainbow trout using, for the first time, progeny testing data to assess the accuracy of GEBVs, and it provides the basis for further investigation on the implementation of GS in commercial rainbow trout populations.

Evaluation of Genome-Enabled Selection for Bacterial Cold Water Disease Resistance Using Progeny Performance Data in Rainbow Trout: Insights on Genotyping Methods and Genomic Prediction Models

PubMed Central

Vallejo, Roger L.; Leeds, Timothy D.; Fragomeni, Breno O.; Gao, Guangtu; Hernandez, Alvaro G.; Misztal, Ignacy; Welch, Timothy J.; Wiens, Gregory D.; Palti, Yniv

2016-01-01

Bacterial cold water disease (BCWD) causes significant economic losses in salmonid aquaculture, and traditional family-based breeding programs aimed at improving BCWD resistance have been limited to exploiting only between-family variation. We used genomic selection (GS) models to predict genomic breeding values (GEBVs) for BCWD resistance in 10 families from the first generation of the NCCCWA BCWD resistance breeding line, compared the predictive ability (PA) of GEBVs to pedigree-based estimated breeding values (EBVs), and compared the impact of two SNP genotyping methods on the accuracy of GEBV predictions. The BCWD phenotypes survival days (DAYS) and survival status (STATUS) had been recorded in training fish (n = 583) subjected to experimental BCWD challenge. Training fish, and their full sibs without phenotypic data that were used as parents of the subsequent generation, were genotyped using two methods: restriction-site associated DNA (RAD) sequencing and the Rainbow Trout Axiom® 57 K SNP array (Chip). Animal-specific GEBVs were estimated using four GS models: BayesB, BayesC, single-step GBLUP (ssGBLUP), and weighted ssGBLUP (wssGBLUP). Family-specific EBVs were estimated using pedigree and phenotype data in the training fish only. The PA of EBVs and GEBVs was assessed by correlating mean progeny phenotype (MPP) with mid-parent EBV (family-specific) or GEBV (animal-specific). The best GEBV predictions were similar to EBV with PA values of 0.49 and 0.46 vs. 0.50 and 0.41 for DAYS and STATUS, respectively. Among the GEBV prediction methods, ssGBLUP consistently had the highest PA. The RAD genotyping platform had GEBVs with similar PA to those of GEBVs from the Chip platform. The PA of ssGBLUP and wssGBLUP methods was higher with the Chip, but for BayesB and BayesC methods it was higher with the RAD platform. The overall GEBV accuracy in this study was low to moderate, likely due to the small training sample used. This study explored the potential of GS for improving resistance to BCWD in rainbow trout using, for the first time, progeny testing data to assess the accuracy of GEBVs, and it provides the basis for further investigation on the implementation of GS in commercial rainbow trout populations. PMID:27303436

Improving accuracy of genomic prediction in Brangus cattle by adding animals with imputed low-density SNP genotypes.

PubMed

Lopes, F B; Wu, X-L; Li, H; Xu, J; Perkins, T; Genho, J; Ferretti, R; Tait, R G; Bauck, S; Rosa, G J M

2018-02-01

Reliable genomic prediction of breeding values for quantitative traits requires the availability of sufficient number of animals with genotypes and phenotypes in the training set. As of 31 October 2016, there were 3,797 Brangus animals with genotypes and phenotypes. These Brangus animals were genotyped using different commercial SNP chips. Of them, the largest group consisted of 1,535 animals genotyped by the GGP-LDV4 SNP chip. The remaining 2,262 genotypes were imputed to the SNP content of the GGP-LDV4 chip, so that the number of animals available for training the genomic prediction models was more than doubled. The present study showed that the pooling of animals with both original or imputed 40K SNP genotypes substantially increased genomic prediction accuracies on the ten traits. By supplementing imputed genotypes, the relative gains in genomic prediction accuracies on estimated breeding values (EBV) were from 12.60% to 31.27%, and the relative gain in genomic prediction accuracies on de-regressed EBV was slightly small (i.e. 0.87%-18.75%). The present study also compared the performance of five genomic prediction models and two cross-validation methods. The five genomic models predicted EBV and de-regressed EBV of the ten traits similarly well. Of the two cross-validation methods, leave-one-out cross-validation maximized the number of animals at the stage of training for genomic prediction. Genomic prediction accuracy (GPA) on the ten quantitative traits was validated in 1,106 newly genotyped Brangus animals based on the SNP effects estimated in the previous set of 3,797 Brangus animals, and they were slightly lower than GPA in the original data. The present study was the first to leverage currently available genotype and phenotype resources in order to harness genomic prediction in Brangus beef cattle. © 2018 Blackwell Verlag GmbH.

Short communication prevalence of susceptibility to etravirine by genotype and phenotype in samples received for routine HIV type 1 resistance testing in the United States.

PubMed

Picchio, Gaston; Vingerhoets, Johan; Tambuyzer, Lotke; Coakley, Eoin; Haddad, Mojgan; Witek, James

2011-12-01

Abstract The prevalence of susceptibility to etravirine was investigated among clinical samples submitted for routine clinical testing in the United States using two separate weighted genotypic scoring systems. The presence of etravirine mutations and susceptibility to etravirine by phenotype of clinical samples from HIV-1-infected patients, submitted to Monogram Biosciences for routine resistance testing between June 2008 and June 2009, were analyzed. Susceptibility by genotype was determined using the Monogram and Tibotec etravirine-weighted genotypic scoring systems, with scores of ≤3 and ≤2, respectively, indicating full susceptibility. Susceptibility by phenotype was determined using the PhenoSense HIV assay, with lower and higher clinical cut-offs of 2.9 and 10, respectively. The frequency of individual etravirine mutations and the impact of the K103N mutation on susceptibility to etravirine by genotype were also determined. Among the 5482 samples with ≥1 defined nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations associated with resistance, 67% were classed as susceptible to etravirine by genotype by both scoring systems. Susceptibility to etravirine by phenotype was higher (76%). The proportion of first-generation NNRTI-resistant samples with (n=3598) and without (n=1884) K103N with susceptibility to etravirine by genotype was 77% and 49%, respectively. Among samples susceptible to first-generation NNRTIs (n=9458), >99% of samples were susceptible to etravirine by phenotype (FC <2.9); the remaining samples had FC ≥2.9-10. In summary, among samples submitted for routine clinical testing in the United States, a high proportion of samples with first-generation NNRTI resistance was susceptible to etravirine by genotype and phenotype. A higher proportion of NNRTI-resistant samples with K103N than without was susceptible to etravirine.

Evidence of an association between 10/10 genotype of DAT1 and endophenotypes of attention deficit/hyperactivity disorder.

PubMed

Agudelo, J A; Gálvez, J M; Fonseca, D J; Mateus, H E; Talero-Gutiérrez, C; Velez-Van-Meerbeke, A

2015-04-01

Genetic variance of attention deficit-hyperactivity disorder (ADHD) is a strong determinant of this disorder. The 40 base pairs (bp) variable number tandem repeat (VNTR) located in the 3' untranslated region (UTR) of DAT1 gene increases the expression of the dopamine transporter. Therefore, DAT1 has been associated with susceptibility to ADHD. To determine the association between the VNTR of DAT1 and the phenotype of ADHD or its endophenotypes in a sample of children aged between 6 and 15 years from Bogotá. We selected 73 patients with ADHD and 54 controls. WISC test was applied in all subjects and executive functions were assessed. The VNTR of DAT1 was polymerase chain reaction-amplified. Data regarding population genetics and statistical analysis were obtained. Correlation and association tests between genotype and neuropsychological testing were performed. The DAT1 polymorphism was not associated with ADHD (P=.85). Nevertheless, the 10/10 genotype was found to be correlated with the processing speed index (P<.05). In the hyperactivity subtype, there was a genotypic correlation with some subtests of executive function (cognitive flexibility) (P≤.01). In the combined subtype, the 10/10 genotype was associated with verbal comprehension index of WISC (P<.05). A correlation was found between DAT1 VNTR and the subtest "processing speed index" of WISC and the subtest "cognitive flexibility" of executive functions. To our knowledge, this is the first report to assess DAT1 gene in a Colombian population. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Genotype–phenotype correlation among beta-thalassemia and beta-thalassemia/HbE disease in Thai children: predictable clinical spectrum using genotypic analysis

PubMed Central

Traivaree, Chanchai; Monsereenusorn, Chalinee; Rujkijyanont, Piya; Prasertsin, Warakorn; Boonyawat, Boonchai

2018-01-01

Introduction Beta-thalassemia is a group of inherited hemolytic anemias and one of the most common genetic disorders in Thailand. The clinical spectrum of beta-thalassemia disease ranges from mild to severe clinical symptoms including mild beta-thalassemia intermedia (TI) and severe beta-thalassemia major (TM). Objective This study aimed to determine the correlation between beta-globin gene (HBB) mutations and their phenotypic manifestations by evaluating patients’ clinical characteristics, transfusion requirements, growth and hematologic parameters, and hemoglobin typing among pediatric patients treated at Phramongkutklao Hospital. Materials and methods Seventy beta-thalassemia patients, including 63 with beta-thalassemia/hemoglobin E (HbE) and 7 with either homozygous or compound heterozygous beta-thalassemia, were enrolled in this study. Their clinical presentation, growth parameters and laboratory findings were reviewed and analyzed. The mean follow-up time was 10.52±5.62 years. Mutation analysis in each individual was performed using multiplex amplification refractory mutation system (M-ARMS), direct DNA sequencing of beta-globin gene and gap PCR for 3.4 kb deletion detection. Results All 7 homozygous and compound heterozygous beta-thalassemia patients were classified in TM. Among 63 patients with beta-thalassemia/HbE, 58 were classified in TM and 4 were classified in TI. Mean age at diagnosis was 0.8±0.49 years for homozygous or compound heterozygous beta-thalassemia and 3.43±3.5 years for beta-thalassemia/HbE. The most common HBB mutation was HBB:c.126_129delCTTT [codon 41/42 (-TCTT)] found in 34 alleles (48.6%). The height for age was also lower in homozygous beta-thalassemia patients (<3rd percentile) compared to compound heterozygous beta-thalassemia patients (25–50th percentile). Conclusion This study revealed a genotype–phenotype correlation of the most prevalent beta-thalassemia in Thai children using diagnostic capacity in genotypic analysis of HBB mutation. Our findings can provide a better prediction of clinical manifestation and severity by early identification of the type of the HBB mutations. PMID:29695942

Mutation Spectrum of the LRP5, NDP, and TSPAN12 Genes in Chinese Patients With Familial Exudative Vitreoretinopathy.

PubMed

Tang, Miao; Sun, Limei; Hu, Andina; Yuan, Miner; Yang, Yu; Peng, Xuening; Ding, Xiaoyan

2017-11-01

LRP5, NDP, and TSPAN12 are known to be associated with familial exudative vitreoretinopathy (FEVR). In this study, a comprehensive mutation screening for the three genes was performed in patients with a clinical diagnosis of FEVR in Han Chinese. Genomic DNA and clinical data were collected from 100 probands and their family members. Sanger sequencing was performed to screen for LRP5, NDP, and TSPAN12 mutations and phenotype-genotype correlation was analyzed. There were 23 causative mutations identified in 23 unrelated probands (10/23 in LRP5, 8/23 in TSPAN12, and 5/23 in NDP). Apart from NDP mutations, only two LRP5 mutations inherited in an autosomal recessive manner. Among the 23 causative mutations, 13 were novel variants (4/10 in LRP5, 6/8 in TSPAN12, and 3/5 in NDP). According to the modified classification system, statistical significance was observed in the distribution of mutated genes (P = 0.049). None of the causative mutations was found in group I FEVR. Probands with LRP5 or NDP mutations were mainly categorized into group III and IV, TSPAN12 mutations were mainly observed in probands with group IV and V FEVR. The detection rate for mutations in the three known genes was 23%. Mutations in LRP5 and TSPAN12 were more frequent, accounting for 10% and 8%, respectively. The NDP mutations were only identified in 6% in this cohort. There were 13 novel variants found, which provided a deeper understanding of this disease. Potential phenotype-genotype correlation was observed in the modified system. TSPAN12 mutations might lead to the most severe phenotype.

Two novel de novo mutations of KRT6A and KRT16 genes in two Chinese pachyonychia congenita pedigrees with fissured tongue or diffuse plantar keratoderma.

PubMed

Du, Zhen-Fang; Xu, Chen-Ming; Zhao, Yan; Liu, Wen-Ting; Chen, Xiao-Ling; Chen, Chun-Yue; Fang, Hong; Ke, Hai-Ping; Zhang, Xian-Ning

2012-01-01

Mutations in the KRT6A or KRT16 gene cause pachyonychia congenita type 1 (PC-1), while mutations in KRT16 or KRT6C underlie focal palmoplantar keratoderma (FPPK). A new classification system of PC has been adopted based on the mutated gene. PC rarely presents the symptoms of diffuse plantar keratoderma. Mutation in the tail domain of keratins is rarely reported. PC combined with fissured tongue has never been described. To investigate the genotype-phenotype correlations between clinical features and gene mutational sites in two unrelated southern Chinese PC pedigrees (one family presented with specific fissured tongue, the other with diffuse plantar keratoderma). The whole coding regions of the KRT6A/KRT16/KRT17/KRT6B genes were amplified and directly sequenced to detect the mutation. To confirm the effect of the IVS8-2A>C mutation in KRT6A at the mRNA level, total RNA from the plantar lesion of a patient was extracted and reverse-transcribed to cDNA for sequence analysis. Two novel de novo mutations, a splice acceptor site variant IVS8-2A>C (p.S487FfsX72) in KRT6A and a heterozygous substitution c.AA373_374GG (p.N125G) within exon 1 of KRT16, were found separately in the two PC families. Genotype-phenotype correlations among PC patients with codon-125 mutation in KRT16 were established, while the phenotypes caused by the IVS8-2A>C mutation in KRT6A need further studies to confirm the rare feature of fissured tongue.

Insights into Mutation Effect in Three Poikiloderma with Neutropenia Patients by Transcript Analysis and Disease Evolution of Reported Patients with the Same Pathogenic Variants.

PubMed

Colombo, Elisa A; Elcioglu, Nursel H; Graziano, Claudio; Farinelli, Pamela; Di Fede, Elisabetta; Neri, Iria; Facchini, Elena; Greco, Mariangela; Gervasini, Cristina; Larizza, Lidia

2018-05-16

Poikiloderma with neutropenia (PN) is a genodermatosis currently described in 77 patients, all presenting with early-onset poikiloderma, neutropenia, and several additional signs. Biallelic loss-of-function mutations in USB1 gene are detected in all molecularly tested patients but genotype-phenotype correlation remains elusive. Cancer predisposition is recognized among PN features and pathogenic variants found in patients who developed early in life myelodysplasia (n = 12), acute myeloid leukemia (n = 2), and squamous cell carcinoma (n = 2) should be kept into account in management and follow-up of novel patients. This will hopefully allow achieving data clustered on specific mutations relevant to oncological surveillance of the carrier patients. We describe the clinical features of three unreported PN patients and characterize their USB1 pathogenic variants by transcript analysis to get insights into the effect on the overall phenotype and disease evolution. A Turkish boy is homozygous for the c.531delA deletion, a recurrent mutation in Turkey; an adult Italian male is compound heterozygous for two nonsense mutations, c.243G>A and c.541C>T, while an Italian boy is homozygous for the splicing c.683_693+1del variant. The identified mutations have already been reported in PN patients who developed hematologic or skin cancer. Aberrant mRNAs of all four mutated alleles could be identified confirming that transcripts of USB1 main isoform either carrying stop codons or mis-spliced may at least partially escape nonsense-mediated decay. Our study addresses the need of gathering insights on genotype-phenotype correlations in newly described PN patients, by transcript analysis and information on disease evolution of reported patients with the same pathogenic variants.

Centronuclear myopathies: genotype-phenotype correlation and frequency of defined genetic forms in an Italian cohort.

PubMed

Fattori, Fabiana; Maggi, Lorenzo; Bruno, Claudio; Cassandrini, Denise; Codemo, Valentina; Catteruccia, Michela; Tasca, Giorgio; Berardinelli, Angela; Magri, Francesca; Pane, Marika; Rubegni, Anna; Santoro, Lucio; Ruggiero, Lucia; Fiorini, Patrizio; Pini, Antonella; Mongini, Tiziana; Messina, Sonia; Brisca, Giacomo; Colombo, Irene; Astrea, Guja; Fiorillo, Chiara; Bragato, Cinzia; Moroni, Isabella; Pegoraro, Elena; D'Apice, Maria Rosaria; Alfei, Enrico; Mora, Marina; Morandi, Lucia; Donati, Alice; Evilä, Anni; Vihola, Anna; Udd, Bjarne; Bernansconi, Pia; Mercuri, Eugenio; Santorelli, Filippo Maria; Bertini, Enrico; D'Amico, Adele

2015-07-01

Centronuclear myopathies (CNMs) are a group of clinically and genetically heterogeneous muscle disorders. To date, mutation in 7 different genes has been reported to cause CNMs but 30 % of cases still remain genetically undefined. Genetic investigations are often expensive and time consuming. Clinical and morphological clues are needed to facilitate genetic tests and to choose the best approach for genetic screening. We aimed to describe genotype-phenotype correlation in an Italian cohort of patients affected by CNMs, to define the relative frequencies of its defined genetic forms and to draw a diagnostic algorithm to address genetic investigations. We recruited patients with CNMs from all the Italian tertiary neuromuscular centers following clinical and histological criteria. All selected patients were screened for the four 'canonical' genes related to CNMs: MTM1, DNM2, RYR1 and BIN1. Pathogenetic mutations were found in 38 of the 54 screened patients (70 %), mostly in patients with congenital onset (25 of 30 patients, 83 %): 15 in MTM1, 6 in DNM2, 3 in RYR1 and one in TTN. Among the 13 patients with a childhood-adolescence onset, mutations were found in 6 patients (46 %), all in DNM2. In the group of the 11 patients with adult onset, mutations were identified in 7 patients (63 %), again in DNM2, confirming that variants in this gene are relatively more common in late-onset phenotypes. The present study provides the relative molecular frequency of centronuclear myopathy and of its genetically defined forms in Italy and also proposes a diagnostic algorithm to be used in clinical practice to address genetic investigations.

Identification of novel deletions of 15q11q13 in Angelman syndrome by array-CGH: molecular characterization and genotype-phenotype correlations.

PubMed

Sahoo, Trilochan; Bacino, Carlos A; German, Jennifer R; Shaw, Chad A; Bird, Lynne M; Kimonis, Virginia; Anselm, Irinia; Waisbren, Susan; Beaudet, Arthur L; Peters, Sarika U

2007-09-01

Angelman syndrome (AS) is a neurodevelopmental disorder characterized by mental retardation, absent speech, ataxia, and a happy disposition. Deletions of the 15q11q13 region are found in approximately 70% of AS patients. The deletions are sub-classified into class I and class II based on their sizes of approximately 6.8 and approximately 6.0, respectively, with two different proximal breakpoints and a common distal breakpoint. Utilizing a chromosome 15-specific comparative genomic hybridization genomic microarray (array-CGH), we have identified, determined the deletion sizes, and mapped the breakpoints in a cohort of 44 cases, to relate those breakpoints to the genomic architecture and derive more precise genotype-phenotype correlations. Interestingly four patients of the 44 studied (9.1%) had novel and unusually large deletions, and are reported here. This is the first report of very large deletions of 15q11q13 resulting in AS; the largest deletion being >10.6 Mb. These novel deletions involve three different distal breakpoints, two of which have been earlier shown to be involved in the generation of isodicentric 15q chromosomes (idic15). Additionally, precise determination of the deletion breakpoints reveals the presence of directly oriented low-copy repeats (LCRs) flanking the recurrent and novel breakpoints. The LCRs are adequate in size, orientation, and homology to enable abnormal recombination events leading to deletions and duplications. This genomic organization provides evidence for a common mechanism for the generation of both common and rare deletion types. Larger deletions result in a loss of several genes outside the common Angelman syndrome-Prader-Willi syndrome (AS-PWS) critical interval, and a more severe phenotype.

A comprehensive global genotype-phenotype database for rare diseases.

PubMed

Trujillano, Daniel; Oprea, Gabriela-Elena; Schmitz, Yvonne; Bertoli-Avella, Aida M; Abou Jamra, Rami; Rolfs, Arndt

2017-01-01

The ability to discover genetic variants in a patient runs far ahead of the ability to interpret them. Databases with accurate descriptions of the causal relationship between the variants and the phenotype are valuable since these are critical tools in clinical genetic diagnostics. Here, we introduce a comprehensive and global genotype-phenotype database focusing on rare diseases. This database (CentoMD ® ) is a browser-based tool that enables access to a comprehensive, independently curated system utilizing stringent high-quality criteria and a quickly growing repository of genetic and human phenotype ontology (HPO)-based clinical information. Its main goals are to aid the evaluation of genetic variants, to enhance the validity of the genetic analytical workflow, to increase the quality of genetic diagnoses, and to improve evaluation of treatment options for patients with hereditary diseases. The database software correlates clinical information from consented patients and probands of different geographical backgrounds with a large dataset of genetic variants and, when available, biomarker information. An automated follow-up tool is incorporated that informs all users whenever a variant classification has changed. These unique features fully embedded in a CLIA/CAP-accredited quality management system allow appropriate data quality and enhanced patient safety. More than 100,000 genetically screened individuals are documented in the database, resulting in more than 470 million variant detections. Approximately, 57% of the clinically relevant and uncertain variants in the database are novel. Notably, 3% of the genetic variants identified and previously reported in the literature as being associated with a particular rare disease were reclassified, based on internal evidence, as clinically irrelevant. The database offers a comprehensive summary of the clinical validity and causality of detected gene variants with their associated phenotypes, and is a valuable tool for identifying new disease genes through the correlation of novel genetic variants with specific, well-defined phenotypes.

Correlation of genetic and clinical findings in Spanish patients with X-linked juvenile retinoschisis.

PubMed

Riveiro-Alvarez, Rosa; Trujillo-Tiebas, Maria-Jose; Gimenez-Pardo, Ascension; Garcia-Hoyos, Maria; Lopez-Martinez, Miguel-Angel; Aguirre-Lamban, Jana; Garcia-Sandoval, Blanca; Vazquez-Fernandez del Pozo, Silvia; Cantalapiedra, Diego; Avila-Fernandez, Almudena; Baiget, Montserrat; Ramos, Carmen; Ayuso, Carmen

2009-09-01

X-linked juvenile retinoschisis (XLRS) is one of the most common causes of juvenile macular degeneration in males, characterized by microcystic changes, splitting within the inner retinal layer (schisis), and the presence of vitreous veils. This study was conducted to describe and further correlate specific genetic variation in Spanish patients with XLRS with clinical characteristics and additional ophthalmic complications. The study was performed in 34 Spanish families with XLRS, comprising 51 affected males. Thorough clinical ophthalmic and electrophysiological examinations were performed. The coding regions of the RS1 gene were amplified by polymerase chain reaction and directly sequenced. Haplotype analyses were also performed. Twenty different mutations were identified. Ten of the 20 were novel and 3 were de novo mutational events. The most common mutation (p.Gln154Arg; 6/20) presented a common haplotype. RS1 variants did not correlate with ophthalmic findings and were not associated with additional ophthalmic complications. The prevalent p.Gln154Arg mutation is first reported in this work and presents a common origin in Spanish patients with XLRS. In addition, de novo mutations mainly occur in CG dinucleotides. Despite the large mutational spectrum and variable phenotypes, no genotype-phenotype correlations were found. Identifying the causative mutation is helpful in confirming diagnosis and counseling, but cannot provide a prognosis.

Genome-Wide Association Analysis of Adaptation Using Environmentally Predicted Traits.

PubMed

van Heerwaarden, Joost; van Zanten, Martijn; Kruijer, Willem

2015-10-01

Current methods for studying the genetic basis of adaptation evaluate genetic associations with ecologically relevant traits or single environmental variables, under the implicit assumption that natural selection imposes correlations between phenotypes, environments and genotypes. In practice, observed trait and environmental data are manifestations of unknown selective forces and are only indirectly associated with adaptive genetic variation. In theory, improved estimation of these forces could enable more powerful detection of loci under selection. Here we present an approach in which we approximate adaptive variation by modeling phenotypes as a function of the environment and using the predicted trait in multivariate and univariate genome-wide association analysis (GWAS). Based on computer simulations and published flowering time data from the model plant Arabidopsis thaliana, we find that environmentally predicted traits lead to higher recovery of functional loci in multivariate GWAS and are more strongly correlated to allele frequencies at adaptive loci than individual environmental variables. Our results provide an example of the use of environmental data to obtain independent and meaningful information on adaptive genetic variation.

Genome-wide association analysis of secondary imaging phenotypes from the Alzheimer's disease neuroimaging initiative study.

PubMed

Zhu, Wensheng; Yuan, Ying; Zhang, Jingwen; Zhou, Fan; Knickmeyer, Rebecca C; Zhu, Hongtu

2017-02-01

The aim of this paper is to systematically evaluate a biased sampling issue associated with genome-wide association analysis (GWAS) of imaging phenotypes for most imaging genetic studies, including the Alzheimer's Disease Neuroimaging Initiative (ADNI). Specifically, the original sampling scheme of these imaging genetic studies is primarily the retrospective case-control design, whereas most existing statistical analyses of these studies ignore such sampling scheme by directly correlating imaging phenotypes (called the secondary traits) with genotype. Although it has been well documented in genetic epidemiology that ignoring the case-control sampling scheme can produce highly biased estimates, and subsequently lead to misleading results and suspicious associations, such findings are not well documented in imaging genetics. We use extensive simulations and a large-scale imaging genetic data analysis of the Alzheimer's Disease Neuroimaging Initiative (ADNI) data to evaluate the effects of the case-control sampling scheme on GWAS results based on some standard statistical methods, such as linear regression methods, while comparing it with several advanced statistical methods that appropriately adjust for the case-control sampling scheme. Copyright © 2016 Elsevier Inc. All rights reserved.

The BAG3 gene variants in Polish patients with dilated cardiomyopathy: four novel mutations and a genotype-phenotype correlation.

PubMed

Franaszczyk, Maria; Bilinska, Zofia T; Sobieszczańska-Małek, Małgorzata; Michalak, Ewa; Sleszycka, Justyna; Sioma, Agnieszka; Małek, Łukasz A; Kaczmarska, Dorota; Walczak, Ewa; Włodarski, Paweł; Hutnik, Łukasz; Milanowska, Blanka; Dzielinska, Zofia; Religa, Grzegorz; Grzybowski, Jacek; Zieliński, Tomasz; Ploski, Rafal

2014-07-09

BAG3 gene mutations have been recently implicated as a novel cause of dilated cardiomyopathy (DCM). Our aim was to evaluate the prevalence of BAG3 mutations in Polish patients with DCM and to search for genotype-phenotype correlations. We studied 90 unrelated probands by direct sequencing of BAG3 exons and splice sites. Large deletions/insertions were screened for by quantitative real time polymerase chain reaction (qPCR). We found 5 different mutations in 6 probands and a total of 21 mutations among their relatives: the known p.Glu455Lys mutation (2 families), 4 novel mutations: p.Gln353ArgfsX10 (c.1055delC), p.Gly379AlafsX45 (c.1135delG), p.Tyr451X (c.1353C>A) and a large deletion of 17,990 bp removing BAG3 exons 3-4. Analysis of mutation positive relatives of the probands from this study pooled with those previously reported showed higher DCM prevalence among those with missense vs. truncating mutations (OR = 8.33, P = 0.0058) as well as a difference in age at disease onset between the former and the latter in Kaplan-Meier survival analysis (P = 0.006). Clinical data from our study suggested that in BAG3 mutation carriers acute onset DCM with hemodynamic compromise may be triggered by infection. BAG3 point mutations and large deletions are relatively frequent cause of DCM. Delayed DCM onset associated with truncating vs. non-truncating mutations may be important for genetic counseling.

Microarray and FISH-based genotype-phenotype analysis of 22 Japanese patients with Wolf-Hirschhorn syndrome.

PubMed

Shimizu, Kenji; Wakui, Keiko; Kosho, Tomoki; Okamoto, Nobuhiko; Mizuno, Seiji; Itomi, Kazuya; Hattori, Shigeto; Nishio, Kimio; Samura, Osamu; Kobayashi, Yoshiyuki; Kako, Yuko; Arai, Takashi; Tsutomu, Oh-ishi; Kawame, Hiroshi; Narumi, Yoko; Ohashi, Hirofumi; Fukushima, Yoshimitsu

2014-03-01

Wolf-Hirschhorn syndrome (WHS) is a contiguous gene deletion syndrome of the distal 4p chromosome, characterized by craniofacial features, growth impairment, intellectual disability, and seizures. Although genotype-phenotype correlation studies have previously been published, several important issues remain to be elucidated including seizure severity. We present detailed clinical and molecular-cytogenetic findings from a microarray and fluorescence in situ hybridization (FISH)-based genotype-phenotype analysis of 22 Japanese WHS patients, the first large non-Western series. 4p deletions were terminal in 20 patients and interstitial in two, with deletion sizes ranging from 2.06 to 29.42 Mb. The new Wolf-Hirschhorn syndrome critical region (WHSCR2) was deleted in all cases, and duplication of other chromosomal regions occurred in four. Complex mosaicism was identified in two cases: two different 4p terminal deletions; a simple 4p terminal deletion and an unbalanced translocation with the same 4p breakpoint. Seizures began in infancy in 33% (2/6) of cases with small (<6 Mb) deletions and in 86% (12/14) of cases with larger deletions (>6 Mb). Status epilepticus occurred in 17% (1/6) with small deletions and in 87% (13/15) with larger deletions. Renal hypoplasia or dysplasia and structural ocular anomalies were more prevalent in those with larger deletions. A new susceptible region for seizure occurrence is suggested between 0.76 and 1.3 Mb from 4 pter, encompassing CTBP1 and CPLX1, and distal to the previously-supposed candidate gene LETM1. The usefulness of bromide therapy for seizures and additional clinical features including hypercholesterolemia are also described. © 2013 Wiley Periodicals, Inc.

Genotype-phenotype analysis of a rare type of osteogenesis imperfecta in four Chinese families with WNT1 mutations.

PubMed

Liu, Yi; Song, Lijie; Ma, Doudou; Lv, Fang; Xu, Xiaojie; Wang, Jianyi; Xia, Weibo; Jiang, Yan; Wang, Ou; Song, Yuwen; Xing, Xiaoping; Asan; Li, Mei

2016-10-01

Osteogenesis imperfecta (OI) is a rare inherited disease characterized by increased bone fragility and vulnerability to fractures. Recently, WNT1 is identified as a new candidate gene for OI, here we detect pathogenic mutations in WNT1 and analyze the genotype-phenotype association in four Chinese families with OI. We designed a targeted next generation sequencing panel with known fourteen OI-related genes. We applied the approach to detect pathogenic mutations in OI patients and confirmed the mutations with Sanger sequencing and cosegregation analysis. Clinical fractures, bone mineral density (BMD) and the other clinical manifestations were evaluated. We also observed the effects of bisphosphonates in OI patients with WNT1 mutations. Four compound heterozygous mutations (c.110T>C; c.505 G>T; c. 385G>A; c.506 G>A) in WNT1 were detected in three unrelated families. These four mutations had not been reported yet. A recurrent homozygous mutation (c.506dupG) was identified in the other two families. These patients had moderate to severe OI, white to blue sclera, absence of dentinogenesis imperfecta and no brain malformation. We did not observe clear genotype-phenotype correlation in WNT1 mutated OI patients. Though bisphosphonates increased BMD in WNT1 related OI patients, height did not increase and fracture continued. We reported four novel heterozygous variants and confirmed a previous reported WNT1 mutation in four Chinese families with a clinical diagnosis of OI. Our study expanded OI spectrum and confirmed moderate to severe bone fragility induced by WNT1 defects. Copyright © 2016 Elsevier B.V. All rights reserved.

Neural processing of race by individuals with Williams syndrome: Do they show the other-race effect? (And why it matters)

PubMed Central

Fishman, Inna; Ng, Rowena; Bellugi, Ursula

2012-01-01

Williams syndrome (WS) is a genetic condition with a distinctive social phenotype characterized by excessive sociability, accompanied by a relative proficiency in face recognition, despite severe deficits in visuospatial domain of cognition. This consistent phenotypic characteristic and the relative homogeneity of the WS genotype make WS a compelling human model for examining the genotype-phenotype relations, especially with respect to social behavior. Following up on a recent report suggesting that individuals with WS do not show race bias and racial stereotyping, this study was designed to investigate the neural correlates of the perception of faces from different races, in individuals with WS as compared to typically developing (TD) controls. Caucasian WS and TD participants performed a gender identification task with own-race (White) and other-race (Black) faces while event-related potentials (ERPs) were recorded. In line with previous studies with TD participants, other-race faces elicited larger amplitudes ERPs within the first 200 ms following the face onset, in WS and TD participants alike. These results suggest that, just like their TD counterparts, individuals with WS differentially processed faces of own- vs. other-race, at relatively early stages of processing, starting as early as 115 ms after the face onset. Overall, these results indicate that neural processing of faces in individuals with WS is moderated by race at early perceptual stages, calling for a reconsideration of the previous claim that they are uniquely insensitive to race. PMID:22022973

REEP1 Mutation Spectrum and Genotype/Phenotype Correlation in Hereditary Spastic Paraplegia Type 31

ERIC Educational Resources Information Center

Beetz, Christian; Schule, Rebecca; Deconinck, Tine; Tran-Viet, Khanh-Nhat; Zhu, Hui; Kremer, Berry P. H.; Frints, Suzanna G. M.; van Zelst-Stams, Wendy A. G.; Byrne, Paula; Otto, Susanne; Nygren, Anders O. H.; Baets, Jonathan; Smets, Katrien; Ceulemans, Berten; Dan, Bernard; Nagan, Narasimhan; Kassubek, Jan; Klimpe, Sven; Klopstock, Thomas; Stolze, Henning; Smeets, Hubert J. M.; Schrander-Stumpel, Constance T. R. M.; Hutchinson, Michael; van de Warrenburg, Bart P.; Braastad, Corey; Deufel, Thomas; Pericak-Vance, Margaret; Schols, Ludger; de Jonghe, Peter; Zuchner, Stephan

2008-01-01

Mutations in the receptor expression enhancing protein 1 (REEP1) have recently been reported to cause autosomal dominant hereditary spastic paraplegia (HSP) type SPG31. In a large collaborative effort, we screened a sample of 535 unrelated HSP patients for "REEP1" mutations and copy number variations. We identified 13 novel and 2 known "REEP1"…

Age-specific effects of estrogen receptors' polymorphisms on the bone traits in healthy fertile women: the BONTURNO study

PubMed Central

Massart, Francesco; Marini, Francesca; Bianchi, Gerolamo; Minisola, Salvatore; Luisetto, Giovanni; Pirazzoli, Antonella; Salvi, Sara; Micheli, Dino; Masi, Laura; Brandi, Maria Luisa

2009-01-01

Background Skeletal characteristics such as height (Ht), bone mineral density (BMD) or bone turnover markers are strongly inherited. Common variants in the genes encoding for estrogen receptor alpha (ESR1) and beta (ESR2) are proposed as candidates for influencing bone phenotypes at the population level. Methods We studied 641 healthy premenopausal women aged 20–50 years (yrs) participating into the BONTURNO study. Exclusion criteria were irregular cyclic menses, low trauma fracture, metabolic bone or chronic diseases. Serum C-telopeptide of type I collagen (CTX), osteocalcin (OC), and N-terminal propeptide of type I procollagen (P1NP) were measured in all enrolled subjects, who underwent to lumbar spine (LS), total hip (TH) and femoral neck (FN) BMD evaluation by DXA. Five hundred seventy Caucasian women were genotyped for ESR1 rs2234693 and rs9340799 and ESR2 rs4986938 polymorphisms. Results Although no genotype differences were found in body parameters, subjects with combined ESR1 CCGG plus ESR2 AA-AG genotype were taller than those with opposite genotype (P = 0.044). Moreover, ESR1 rs2234693 genotypes correlated with family history of osteoporosis (FHO) and hip fracture (FHF) (P < 0.01), while ESR2 AA-AC genotypes were strongly associated with FHF (OR 2.387, 95% CI 1.432–3.977; P < 0.001). When clustered by age, 20–30 yrs old subjects, having at least one ESR1 rs2234693 C allele presented lower LS- (P = 0.008) and TH-BMD (P = 0.047) than TT genotypes. In 41–50 yrs age, lower FN-BMD was associated with ESR2 AA (P = 0.0180) subjects than in those with the opposite genotype. ESR1 rs2234693 and rs9340799 and ESR2 rs4986938 polymorphisms did not correlate with age-adjusted values of OC, CTX and P1NP. Conclusion These findings support the presence of age-specific effects of ESR1 and ESR2 polymorphisms on various skeletal traits in healthy fertile women. PMID:19386104

Retinitis pigmentosa: genes and disease mechanisms.

PubMed

Ferrari, Stefano; Di Iorio, Enzo; Barbaro, Vanessa; Ponzin, Diego; Sorrentino, Francesco S; Parmeggiani, Francesco

2011-06-01

Retinitis pigmentosa (RP) is a group of inherited disorders affecting 1 in 3000-7000 people and characterized by abnormalities of the photoreceptors (rods and cones) or the retinal pigment epithelium of the retina which lead to progressive visual loss. RP can be inherited in an autosomal dominant, autosomal recessive or X-linked manner. While usually limited to the eye, RP may also occur as part of a syndrome as in the Usher syndrome and Bardet-Biedl syndrome. Over 40 genes have been associated with RP so far, with the majority of them expressed in either the photoreceptors or the retinal pigment epithelium. The tremendous heterogeneity of the disease makes the genetics of RP complicated, thus rendering genotype-phenotype correlations not fully applicable yet. In addition to the multiplicity of mutations, in fact, different mutations in the same gene may cause different diseases. We will here review which genes are involved in the genesis of RP and how mutations can lead to retinal degeneration. In the future, a more thorough analysis of genetic and clinical data together with a better understanding of the genotype-phenotype correlation might allow to reveal important information with respect to the likelihood of disease development and choices of therapy.

Retinitis Pigmentosa: Genes and Disease Mechanisms

PubMed Central

Ferrari, Stefano; Di Iorio, Enzo; Barbaro, Vanessa; Ponzin, Diego; Sorrentino, Francesco S; Parmeggiani, Francesco

2011-01-01

Retinitis pigmentosa (RP) is a group of inherited disorders affecting 1 in 3000-7000 people and characterized by abnormalities of the photoreceptors (rods and cones) or the retinal pigment epithelium of the retina which lead to progressive visual loss. RP can be inherited in an autosomal dominant, autosomal recessive or X-linked manner. While usually limited to the eye, RP may also occur as part of a syndrome as in the Usher syndrome and Bardet-Biedl syndrome. Over 40 genes have been associated with RP so far, with the majority of them expressed in either the photoreceptors or the retinal pigment epithelium. The tremendous heterogeneity of the disease makes the genetics of RP complicated, thus rendering genotype-phenotype correlations not fully applicable yet. In addition to the multiplicity of mutations, in fact, different mutations in the same gene may cause different diseases. We will here review which genes are involved in the genesis of RP and how mutations can lead to retinal degeneration. In the future, a more thorough analysis of genetic and clinical data together with a better understanding of the genotype-phenotype correlation might allow to reveal important information with respect to the likelihood of disease development and choices of therapy. PMID:22131869

SEE locomotor behavior test discriminates C57BL/6J and DBA/2J mouse inbred strains across laboratories and protocol conditions.

PubMed

Kafkafi, Neri; Lipkind, Dina; Benjamini, Yoav; Mayo, Cheryl L; Elmer, Gregory I; Golani, Ilan

2003-06-01

Conventional tests of behavioral phenotyping frequently have difficulties differentiating certain genotypes and replicating these differences across laboratories and protocol conditions. This study explores the hypothesis that automated tests can be designed to quantify ethologically relevant behavior patterns that more readily characterize heritable and replicable phenotypes. It used SEE (Strategy for the Exploration of Exploration) to phenotype the locomotor behavior of the C57BL/6 and DBA/2 mouse inbred strains across 3 laboratories. The 2 genotypes differed in 15 different measures of behavior, none of which had a significant genotype-laboratory interaction. Within the same laboratory, most of these differences were replicated in additional experiments despite the test photoperiod phase being changed and saline being injected. Results suggest that well-designed tests may considerably enhance replicability across laboratories.

Poor phenotype-genotype association in a large series of patients with Type III Bartter syndrome.

PubMed

García Castaño, Alejandro; Pérez de Nanclares, Gustavo; Madariaga, Leire; Aguirre, Mireia; Madrid, Álvaro; Chocrón, Sara; Nadal, Inmaculada; Navarro, Mercedes; Lucas, Elena; Fijo, Julia; Espino, Mar; Espitaletta, Zilac; García Nieto, Víctor; Barajas de Frutos, David; Loza, Reyner; Pintos, Guillem; Castaño, Luis; Ariceta, Gema

2017-01-01

Type III Bartter syndrome (BS) is an autosomal recessive renal tubule disorder caused by loss-of-function mutations in the CLCNKB gene, which encodes the chloride channel protein ClC-Kb. In this study, we carried out a complete clinical and genetic characterization in a cohort of 30 patients, one of the largest series described. By comparing with other published populations, and considering that 80% of our patients presented the p.Ala204Thr Spanish founder mutation presumably associated with a common phenotype, we aimed to test the hypothesis that allelic differences could explain the wide phenotypic variability observed in patients with type III BS. Clinical data were retrieved from the referral centers. The exon regions and flanking intronic sequences of the CLCNKB gene were screened for mutations by polymerase chain reaction (PCR) followed by direct Sanger sequencing. Presence of gross deletions or duplications in the region was checked for by MLPA and QMPSF analyses. Polyuria, polydipsia and dehydration were the main common symptoms. Metabolic alkalosis and hypokalemia of renal origin were detected in all patients at diagnosis. Calciuria levels were variable: hypercalciuria was detected in 31% of patients, while 23% had hypocalciuria. Nephrocalcinosis was diagnosed in 20% of the cohort. Two novel CLCNKB mutations were identified: a small homozygous deletion (c.753delG) in one patient and a small deletion (c.1026delC) in another. The latter was present in compound heterozygosis with the already previously described p.Glu442Gly mutation. No phenotypic association was obtained regarding the genotype. A poor correlation was found between a specific type of mutation in the CLCNKB gene and type III BS phenotype. Importantly, two CLCNKB mutations not previously described were found in our cohort.

The phenotypic spectrum in patients with arginine to cysteine mutations in the COL2A1 gene

PubMed Central

Hoornaert, K P; Dewinter, C; Vereecke, I; Beemer, F A; Courtens, W; Fryer, A; Fryssira, H; Lees, M; Müllner‐Eidenböck, A; Rimoin, D L; Siderius, L; Superti‐Furga, A; Temple, K; Willems, P J; Zankl, A; Zweier, C; De Paepe, A; Coucke, P; Mortier, G R

2006-01-01

Background The majority of COL2A1 missense mutations are substitutions of obligatory glycine residues in the triple helical domain. Only a few non‐glycine missense mutations have been reported and among these, the arginine to cysteine substitutions predominate. Objective To investigate in more detail the phenotype resulting from arginine to cysteine mutations in the COL2A1 gene. Methods The clinical and radiographic phenotype of all patients in whom an arginine to cysteine mutation in the COL2A1 gene was identified in our laboratory, was studied and correlated with the abnormal genotype. The COL2A1 genotyping involved DHPLC analysis with subsequent sequencing of the abnormal fragments. Results Six different mutations (R75C, R365C, R519C, R704C, R789C, R1076C) were found in 11 unrelated probands. Each mutation resulted in a rather constant and site‐specific phenotype, but a perinatally lethal disorder was never observed. Spondyloarthropathy with normal stature and no ocular involvement were features of patients with the R75C, R519C, or R1076C mutation. Short third and/or fourth toes was a distinguishing feature of the R75C mutation and brachydactyly with enlarged finger joints a key feature of the R1076C substitution. Stickler dysplasia with brachydactyly was observed in patients with the R704C mutation. The R365C and R789C mutations resulted in classic Stickler dysplasia and spondyloepiphyseal dysplasia congenita (SEDC), respectively. Conclusions Arginine to cysteine mutations are rather infrequent COL2A1 mutations which cause a spectrum of phenotypes including classic SEDC and Stickler dysplasia, but also some unusual entities that have not yet been recognised and described as type II collagenopathies. PMID:16155195

Poor phenotype-genotype association in a large series of patients with Type III Bartter syndrome

PubMed Central

Pérez de Nanclares, Gustavo; Madariaga, Leire; Aguirre, Mireia; Madrid, Álvaro; Chocrón, Sara; Nadal, Inmaculada; Navarro, Mercedes; Lucas, Elena; Fijo, Julia; Espino, Mar; Espitaletta, Zilac; García Nieto, Víctor; Barajas de Frutos, David; Loza, Reyner; Pintos, Guillem; Castaño, Luis; Ariceta, Gema

2017-01-01

Introduction Type III Bartter syndrome (BS) is an autosomal recessive renal tubule disorder caused by loss-of-function mutations in the CLCNKB gene, which encodes the chloride channel protein ClC-Kb. In this study, we carried out a complete clinical and genetic characterization in a cohort of 30 patients, one of the largest series described. By comparing with other published populations, and considering that 80% of our patients presented the p.Ala204Thr Spanish founder mutation presumably associated with a common phenotype, we aimed to test the hypothesis that allelic differences could explain the wide phenotypic variability observed in patients with type III BS. Methods Clinical data were retrieved from the referral centers. The exon regions and flanking intronic sequences of the CLCNKB gene were screened for mutations by polymerase chain reaction (PCR) followed by direct Sanger sequencing. Presence of gross deletions or duplications in the region was checked for by MLPA and QMPSF analyses. Results Polyuria, polydipsia and dehydration were the main common symptoms. Metabolic alkalosis and hypokalemia of renal origin were detected in all patients at diagnosis. Calciuria levels were variable: hypercalciuria was detected in 31% of patients, while 23% had hypocalciuria. Nephrocalcinosis was diagnosed in 20% of the cohort. Two novel CLCNKB mutations were identified: a small homozygous deletion (c.753delG) in one patient and a small deletion (c.1026delC) in another. The latter was present in compound heterozygosis with the already previously described p.Glu442Gly mutation. No phenotypic association was obtained regarding the genotype. Conclusion A poor correlation was found between a specific type of mutation in the CLCNKB gene and type III BS phenotype. Importantly, two CLCNKB mutations not previously described were found in our cohort. PMID:28288174

The endocrine-genetic basis of life-history variation: the relationship between the ecdysteroid titer and morph-specific reproduction in the wing-polymorphic cricket Gryllus firmus.

PubMed

Zera, A J; Bottsford, J

2001-03-01

The hormonal basis of variation in life-history traits is a poorly studied topic in life-history evolution. An important step in identifying the endocrine-genetic causes of life-history variation is documenting statistical and functional associations between hormone titers and genotypes/phenotypes that vary in life-history traits. To this end, we compared the blood ecdysteroid titer and the mass of the ovaries during the first week of adulthood among a flight-capable morph and two flightless morphs of the wing-polymorphic cricket Gryllus firmus. Ecdysteroids are a group of structurally related hormones that regulate many important aspects of reproduction in insects. Both the ecdysteroid titer and ovarian mass were significantly higher in each of two flightless morphs compared with the flight-capable morph throughout the first week of adulthood. Genetically based differences in the ecdysteroid titer and ovarian mass between morphs from different selected lines were similar to phenotypically based differences among morphs from the same control (unselected) lines. By day 7 of adulthood, ovaries were typically 200-400% larger and the ecdysteroid titer was 60-300% higher in flightless versus the flight-capable morph. In addition, highly significant, positive, phenotypic correlations were observed between the ecdysteroid titer and ovarian mass in pooled samples of the two flightless and flight-capable crickets from control lines or from selected lines. The ecdysteroid titer was sufficiently elevated in the flightless morphs to account for their elevated ovarian growth. This is the first direct documentation that naturally occurring phenotypes/genotypes that differ in early fecundity, a key life-history trait, also differ phenotypically and genetically in the titer of a key reproductive hormone that potentially regulates that trait.

Genomic scan as a tool for assessing the genetic component of phenotypic variance in wild populations.

PubMed

Herrera, Carlos M

2012-01-01

Methods for estimating quantitative trait heritability in wild populations have been developed in recent years which take advantage of the increased availability of genetic markers to reconstruct pedigrees or estimate relatedness between individuals, but their application to real-world data is not exempt from difficulties. This chapter describes a recent marker-based technique which, by adopting a genomic scan approach and focusing on the relationship between phenotypes and genotypes at the individual level, avoids the problems inherent to marker-based estimators of relatedness. This method allows the quantification of the genetic component of phenotypic variance ("degree of genetic determination" or "heritability in the broad sense") in wild populations and is applicable whenever phenotypic trait values and multilocus data for a large number of genetic markers (e.g., amplified fragment length polymorphisms, AFLPs) are simultaneously available for a sample of individuals from the same population. The method proceeds by first identifying those markers whose variation across individuals is significantly correlated with individual phenotypic differences ("adaptive loci"). The proportion of phenotypic variance in the sample that is statistically accounted for by individual differences in adaptive loci is then estimated by fitting a linear model to the data, with trait value as the dependent variable and scores of adaptive loci as independent ones. The method can be easily extended to accommodate quantitative or qualitative information on biologically relevant features of the environment experienced by each sampled individual, in which case estimates of the environmental and genotype × environment components of phenotypic variance can also be obtained.

Clinical presentations of 23 half-siblings from a mosaic neurofibromatosis type 1 sperm donor.

PubMed

Ejerskov, C; Farholt, S; Skovby, F; Vestergaard, E M; Haagerup, A

2016-03-01

The Danish sperm donor number 7042 has fathered several offspring with neurofibromatosis type 1 (NF1) worldwide. NF1 is caused by loss-of-function mutations in the NF1 gene and more than 1000 NF1 mutations are identified. Analysis of the donor sperm demonstrated gonosomal mosaicism with an intragenic deletion involving exons 15-29 in the NF1 gene. At the two Danish reference centres for NF1 patients, we evaluated 23 half-siblings from the donor. Nine were diagnosed with NF1. The severity grade of NF1 progressed from minimal to mild/moderate within 3 years of follow-up. The NF1 phenotype shows great variability in intra- and inter-family expressivity and to date only two NF1 genotype-phenotype correlations have been established. This rare possibility of a long-term follow-up of a cohort of half-siblings with NF1 makes further studies including phenotypic variability and search for modifier genes possible. To achieve this goal, we have initiated The International Donor 7042 NF1 Offspring Registry. Research facilitated via this registry may reveal important new knowledge of clinical characteristics and prognostics for the specific NF1 genotype and thereby contribute to future individualised targeted clinical follow-up and treatment. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

BDNF rs6265 methylation and genotype interact on risk for schizophrenia.

PubMed

Ursini, Gianluca; Cavalleri, Tommaso; Fazio, Leonardo; Angrisano, Tiziana; Iacovelli, Luisa; Porcelli, Annamaria; Maddalena, Giancarlo; Punzi, Giovanna; Mancini, Marina; Gelao, Barbara; Romano, Raffaella; Masellis, Rita; Calabrese, Francesca; Rampino, Antonio; Taurisano, Paolo; Di Giorgio, Annabella; Keller, Simona; Tarantini, Letizia; Sinibaldi, Lorenzo; Quarto, Tiziana; Popolizio, Teresa; Caforio, Grazia; Blasi, Giuseppe; Riva, Marco A; De Blasi, Antonio; Chiariotti, Lorenzo; Bollati, Valentina; Bertolino, Alessandro

2016-01-01

Epigenetic mechanisms can mediate gene-environment interactions relevant for complex disorders. The BDNF gene is crucial for development and brain plasticity, is sensitive to environmental stressors, such as hypoxia, and harbors the functional SNP rs6265 (Val(66)Met), which creates or abolishes a CpG dinucleotide for DNA methylation. We found that methylation at the BDNF rs6265 Val allele in peripheral blood of healthy subjects is associated with hypoxia-related early life events (hOCs) and intermediate phenotypes for schizophrenia in a distinctive manner, depending on rs6265 genotype: in ValVal individuals increased methylation is associated with exposure to hOCs and impaired working memory (WM) accuracy, while the opposite is true for ValMet subjects. Also, rs6265 methylation and hOCs interact in modulating WM-related prefrontal activity, another intermediate phenotype for schizophrenia, with an analogous opposite direction in the 2 genotypes. Consistently, rs6265 methylation has a different association with schizophrenia risk in ValVals and ValMets. The relationships of methylation with BDNF levels and of genotype with BHLHB2 binding likely contribute to these opposite effects of methylation. We conclude that BDNF rs6265 methylation interacts with genotype to bridge early environmental exposures to adult phenotypes, relevant for schizophrenia. The study of epigenetic changes in regions containing genetic variation relevant for human diseases may have beneficial implications for the understanding of how genes are actually translated into phenotypes.

Specific CAPN10 gene haplotypes influence the clinical profile of polycystic ovary patients.

PubMed

Gonzalez, Alejandro; Abril, Eduardo; Roca, Alfredo; Aragón, Maria José; Figueroa, Maria José; Velarde, Pilar; Ruiz, Rocío; Fayez, Omar; Galán, José Jorge; Herreros, José Antonio; Real, Luis Miguel; Ruiz, Agustín

2003-11-01

Recently, several research groups have evaluated CAPN10 gene in polycystic ovarian syndrome (PCOS) patients and other phenotypes, including hirsutism or intermediate phenotypes of PCOS. Molecular genetic analysis of CAPN10 gene indicates that different alleles may play a role in PCOS susceptibility and could be associated with idiopathic hirsutism. However, these observations are not exempt from controversy, because independent studies cannot replicate these preliminary findings. We present a haplotype-phenotype correlation study of CAPN10 haplotypes in 148 women showing ecographically detected polycystic ovaries (PCO) combined with one or more of these clinical symptoms: amenorrhea or severe oligomenorrhea, hyperandrogenism, and anovulatory infertility, as well as 93 unrelated controls. We have reconstructed and analyzed 482 CAPN10 haplotypes in patients and controls. We detected the association of UCSNP-44 allele with PCO phenotype in the Spanish population (P = 0.02). In addition, we identified several CAPN10 alleles associated to phenotypic differences observed between PCO patients, such as the presence of hypercholesterolemia (haplotype 1121, P = 0.005), presence of hyperandrogenic features (P = 0.05), and familial cancer incidence (haplotype 1111, P = 0.0005). Our results confirm the association of UCSNP-44 allele with PCO phenotype in the Spanish population. Moreover, we have identified novel candidate risk alleles and genotypes, within CAPN10 gene, that could be associated with important phenotypic and prognosis differences observed in PCOS patients.

Ground Field-Based Hyperspectral Imaging: A Preliminary Study to Assess the Potential of Established Vegetation Indices to Infer Variation in Water-Use Efficiency.

NASA Astrophysics Data System (ADS)

Pelech, E. A.; McGrath, J.; Pederson, T.; Bernacchi, C.

2017-12-01

Increases in the global average temperature will consequently induce a higher occurrence of severe environmental conditions such as drought on arable land. To mitigate these threats, crops for fuel and food must be bred for higher water-use efficiencies (WUE). Defining genomic variation through high-throughput phenotypic analysis in field conditions has the potential to relieve the major bottleneck in linking desirable genetic traits to the associated phenotypic response. This can subsequently enable breeders to create new agricultural germplasm that supports the need for higher water-use efficient crops. From satellites to field-based aerial and ground sensors, the reflectance properties of vegetation measured by hyperspectral imaging is becoming a rapid high-throughput phenotyping technique. A variety of physiological traits can be inferred by regression analysis with leaf reflectance which is controlled by the properties and abundance of water, carbon, nitrogen and pigments. Although, given that the current established vegetation indices are designed to accentuate these properties from spectral reflectance, it becomes a challenge to infer relative measurements of WUE at a crop canopy scale without ground-truth data collection. This study aims to correlate established biomass and canopy-water-content indices with ground-truth data. Five bioenergy sorghum genotypes (Sorghum bicolor L. Moench) that have differences in WUE and wild-type Tobacco (Nicotiana tabacum var. Samsun) under irrigated and rainfed field conditions were examined. A linear regression analysis was conducted to determine if variation in canopy water content and biomass, driven by natural genotypic and artificial treatment influences, can be inferred using established vegetation indices. The results from this study will elucidate the ability of ground field-based hyperspectral imaging to assess variation in water content, biomass and water-use efficiency. This can lead to improved opportunities to select ideal genotypes for an increasing water-limited environment and to help parameterize and validate terrestrial vegetation models that require a better representation of genetic variation within crop species.

Evaluating the frequency and characteristics of seizures in 142 Japanese patients with Prader-Willi syndrome.

PubMed

Takeshita, Eri; Murakami, Nobuyuki; Sakuta, Ryoichi; Nagai, Toshiro

2013-08-01

Prader-Willi syndrome (PWS) has not been widely regarded as a disorder with a risk factor for seizures. We retrospectively investigated the frequency and characteristics of seizures and examined genotype-phenotype correlations with respect to seizures in PWS. We analyzed 142 patients with PWS and identified 31 (22%) with seizures. The most common seizure type was febrile convulsion (12%, 17/142). Epilepsy occurred in 6% of the patients in our cohort (9/142). The frequencies of febrile seizure and epilepsy in PWS were higher than those in the general population. Our study suggested that the frequency of seizures was not associated with genotypes of PWS (P = 0.35). In our study patients with PWS, 68% of the patients with seizures experienced initial episodes before they were 2 years old, and the seizures were relatively easier to manage. Copyright © 2013 Wiley Periodicals, Inc.

What can ancient mummies teach us about atherosclerosis?

PubMed

Wann, Samuel; Thomas, Gregory S

2014-10-01

Ancient mummies have captivated a wide variety of audiences for centuries. In order to better understand the evolution and causative features of atherosclerosis, the Horus group is applying modern scientific methods to study ancient mummies. We have used CT scanning to detect calcification in arteries as an indication of the presence of atherosclerosis, and are correlating these results with cultural and lifestyle features of various populations of ancient people as represented by their ancient mummified remains. We are also pursuing related studies of ancient DNA to define genotypes associated with atherosclerotic phenotypes. Copyright © 2014 Elsevier Inc. All rights reserved.

EHR Big Data Deep Phenotyping

PubMed Central

Lenert, L.; Lopez-Campos, G.

2014-01-01

Summary Objectives Given the quickening speed of discovery of variant disease drivers from combined patient genotype and phenotype data, the objective is to provide methodology using big data technology to support the definition of deep phenotypes in medical records. Methods As the vast stores of genomic information increase with next generation sequencing, the importance of deep phenotyping increases. The growth of genomic data and adoption of Electronic Health Records (EHR) in medicine provides a unique opportunity to integrate phenotype and genotype data into medical records. The method by which collections of clinical findings and other health related data are leveraged to form meaningful phenotypes is an active area of research. Longitudinal data stored in EHRs provide a wealth of information that can be used to construct phenotypes of patients. We focus on a practical problem around data integration for deep phenotype identification within EHR data. The use of big data approaches are described that enable scalable markup of EHR events that can be used for semantic and temporal similarity analysis to support the identification of phenotype and genotype relationships. Conclusions Stead and colleagues’ 2005 concept of using light standards to increase the productivity of software systems by riding on the wave of hardware/processing power is described as a harbinger for designing future healthcare systems. The big data solution, using flexible markup, provides a route to improved utilization of processing power for organizing patient records in genotype and phenotype research. PMID:25123744

Patterns of population structure and environmental associations to aridity across the range of loblolly pine (Pinus taeda L., Pinaceae).

PubMed

Eckert, Andrew J; van Heerwaarden, Joost; Wegrzyn, Jill L; Nelson, C Dana; Ross-Ibarra, Jeffrey; González-Martínez, Santíago C; Neale, David B

2010-07-01

Natural populations of forest trees exhibit striking phenotypic adaptations to diverse environmental gradients, thereby making them appealing subjects for the study of genes underlying ecologically relevant phenotypes. Here, we use a genome-wide data set of single nucleotide polymorphisms genotyped across 3059 functional genes to study patterns of population structure and identify loci associated with aridity across the natural range of loblolly pine (Pinus taeda L.). Overall patterns of population structure, as inferred using principal components and Bayesian cluster analyses, were consistent with three genetic clusters likely resulting from expansions out of Pleistocene refugia located in Mexico and Florida. A novel application of association analysis, which removes the confounding effects of shared ancestry on correlations between genetic and environmental variation, identified five loci correlated with aridity. These loci were primarily involved with abiotic stress response to temperature and drought. A unique set of 24 loci was identified as F(ST) outliers on the basis of the genetic clusters identified previously and after accounting for expansions out of Pleistocene refugia. These loci were involved with a diversity of physiological processes. Identification of nonoverlapping sets of loci highlights the fundamental differences implicit in the use of either method and suggests a pluralistic, yet complementary, approach to the identification of genes underlying ecologically relevant phenotypes.

What affects the predictability of evolutionary constraints using a G-matrix? The relative effects of modular pleiotropy and mutational correlation.

PubMed

Chebib, Jobran; Guillaume, Frédéric

2017-10-01

Phenotypic traits do not always respond to selection independently from each other and often show correlated responses to selection. The structure of a genotype-phenotype map (GP map) determines trait covariation, which involves variation in the degree and strength of the pleiotropic effects of the underlying genes. It is still unclear, and debated, how much of that structure can be deduced from variational properties of quantitative traits that are inferred from their genetic (co) variance matrix (G-matrix). Here we aim to clarify how the extent of pleiotropy and the correlation among the pleiotropic effects of mutations differentially affect the structure of a G-matrix and our ability to detect genetic constraints from its eigen decomposition. We show that the eigenvectors of a G-matrix can be predictive of evolutionary constraints when they map to underlying pleiotropic modules with correlated mutational effects. Without mutational correlation, evolutionary constraints caused by the fitness costs associated with increased pleiotropy are harder to infer from evolutionary metrics based on a G-matrix's geometric properties because uncorrelated pleiotropic effects do not affect traits' genetic correlations. Correlational selection induces much weaker modular partitioning of traits' genetic correlations in absence then in presence of underlying modular pleiotropy. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

The NOD2 p.Leu1007fsX1008 mutation (rs2066847) is a stronger predictor of the clinical course of Crohn's disease than the FOXO3A intron variant rs12212067.

PubMed

Schnitzler, Fabian; Friedrich, Matthias; Wolf, Christiane; Angelberger, Marianne; Diegelmann, Julia; Olszak, Torsten; Beigel, Florian; Tillack, Cornelia; Stallhofer, Johannes; Göke, Burkhard; Glas, Jürgen; Lohse, Peter; Brand, Stephan

2014-01-01

Very recently, a sub-analysis of genome-wide association scans revealed that the non-coding single nucleotide polymorphism (SNP) rs12212067 in the FOXO3A gene is associated with a milder course of Crohn's disease (CD) (Cell 2013;155:57-69). The aim of our study was to evaluate the clinical value of the SNP rs12212067 in predicting the severity of CD by correlating CD patient genotype status with the most relevant complications of CD such as stenoses, fistulas, and CD-related surgery. We genotyped 550 CD patients for rs12212067 (FOXO3A) and the three common CD-associated NOD2 mutations rs2066844, rs2066847, and rs2066847 and performed genotype-phenotype analyses. No significant phenotypic differences were found between the wild-type genotype TT of the FOXO3A SNP rs12212067 and the minor genotypes TG and GG independently from NOD2 variants. The allele frequency of the minor G allele was 12.7%. Age at diagnosis, disease duration, body mass index, surgery rate, stenoses, fistula, need for immunosuppressive therapy, and disease course were not significantly different. In contrast, the NOD2 mutant p.Leu1007fsX1008 (rs2066847) was highly associated with penetrating CD (p = 0.01), the development of fistulas (p = 0.01) and stenoses (p = 0.01), and ileal disease localization (p = 0.03). Importantly, the NOD2 SNP rs2066847 was a strong separator between an aggressive and a mild course of CD (p = 2.99×10(-5)), while the FOXO3A SNP rs12212067 did not separate between mild and aggressive CD behavior in our cohort (p = 0.35). 96.2% of the homozygous NOD2 p.Leu1007fsX1008 carriers had an aggressive disease behavior compared to 69.3% of the patients with the NOD2 wild-type genotype (p = 0.007). In clinical practice, the NOD2 variant p.Leu1007fsX1008 (rs2066847), in particular in homozygous form, is a much stronger marker for a severe clinical phenotype than the FOXO3A rs12212067 SNP for a mild disease course on an individual patient level despite its important impact on the inflammatory response of monocytes.

Phenotypic and molecular characterizations of Yersinia pestis isolates from Kazakhstan and adjacent regions.

PubMed

Lowell, Jennifer L; Zhansarina, Aigul; Yockey, Brook; Meka-Mechenko, Tatyana; Stybayeva, Gulnaz; Atshabar, Bakyt; Nekrassova, Larissa; Tashmetov, Rinat; Kenghebaeva, Kuralai; Chu, May C; Kosoy, Michael; Antolin, Michael F; Gage, Kenneth L

2007-01-01

Recent interest in characterizing infectious agents associated with bioterrorism has resulted in the development of effective pathogen genotyping systems, but this information is rarely combined with phenotypic data. Yersinia pestis, the aetiological agent of plague, has been well defined genotypically on local and worldwide scales using multi-locus variable number tandem repeat analysis (MLVA), with emphasis on evolutionary patterns using old isolate collections from countries where Y. pestis has existed the longest. Worldwide MLVA studies are largely based on isolates that have been in long-term laboratory culture and storage, or on field material from parts of the world where Y. pestis has potentially circulated in nature for thousands of years. Diversity in these isolates suggests that they may no longer represent the wild-type organism phenotypically, including the possibility of altered pathogenicity. This study focused on the phenotypic and genotypic properties of 48 Y. pestis isolates collected from 10 plague foci in and bordering Kazakhstan. Phenotypic characterization was based on diagnostic tests typically performed in reference laboratories working with Y. pestis. MLVA was used to define the genotypic relationships between the central-Asian isolates and a group of North American isolates, and to examine Kazakh Y. pestis diversity according to predefined plague foci and on an intermediate geographical scale. Phenotypic properties revealed that a large portion of this collection lacks one or more plasmids necessary to complete the blocked flea/mammal transmission cycle, has lost Congo red binding capabilities (Pgm-), or both. MLVA analysis classified isolates into previously identified biovars, and in some cases groups of isolates collected within the same plague focus formed a clade. Overall, MLVA did not distinguish unique phylogeographical groups of Y. pestis isolates as defined by plague foci and indicated higher genetic diversity among older biovars.