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Sample records for snp frequency haplotype

  1. Haplotype inference from unphased SNP data in heterozygous polyploids based on SAT

    PubMed Central

    Neigenfind, Jost; Gyetvai, Gabor; Basekow, Rico; Diehl, Svenja; Achenbach, Ute; Gebhardt, Christiane; Selbig, Joachim; Kersten, Birgit

    2008-01-01

    Background Haplotype inference based on unphased SNP markers is an important task in population genetics. Although there are different approaches to the inference of haplotypes in diploid species, the existing software is not suitable for inferring haplotypes from unphased SNP data in polyploid species, such as the cultivated potato (Solanum tuberosum). Potato species are tetraploid and highly heterozygous. Results Here we present the software SATlotyper which is able to handle polyploid and polyallelic data. SATlo-typer uses the Boolean satisfiability problem to formulate Haplotype Inference by Pure Parsimony. The software excludes existing haplotype inferences, thus allowing for calculation of alternative inferences. As it is not known which of the multiple haplotype inferences are best supported by the given unphased data set, we use a bootstrapping procedure that allows for scoring of alternative inferences. Finally, by means of the bootstrapping scores, it is possible to optimise the phased genotypes belonging to a given haplotype inference. The program is evaluated with simulated and experimental SNP data generated for heterozygous tetraploid populations of potato. We show that, instead of taking the first haplotype inference reported by the program, we can significantly improve the quality of the final result by applying additional methods that include scoring of the alternative haplotype inferences and genotype optimisation. For a sub-population of nineteen individuals, the predicted results computed by SATlotyper were directly compared with results obtained by experimental haplotype inference via sequencing of cloned amplicons. Prediction and experiment gave similar results regarding the inferred haplotypes and phased genotypes. Conclusion Our results suggest that Haplotype Inference by Pure Parsimony can be solved efficiently by the SAT approach, even for data sets of unphased SNP from heterozygous polyploids. SATlotyper is freeware and is distributed as

  2. Efficient fast heuristic algorithms for minimum error correction haplotyping from SNP fragments.

    PubMed

    Anaraki, Maryam Pourkamali; Sadeghi, Mehdi

    2014-01-01

    Availability of complete human genome is a crucial factor for genetic studies to explore possible association between the genome and complex diseases. Haplotype, as a set of single nucleotide polymorphisms (SNPs) on a single chromosome, is believed to contain promising data for disease association studies, detecting natural positive selection and recombination hotspots. Various computational methods for haplotype reconstruction from aligned fragment of SNPs have already been proposed. This study presents a novel approach to obtain paternal and maternal haplotypes form the SNP fragments on minimum error correction (MEC) model. Reconstructing haplotypes in MEC model is an NP-hard problem. Therefore, our proposed methods employ two fast and accurate clustering techniques as the core of their procedure to efficiently solve this ill-defined problem. The assessment of our approaches, compared to conventional methods, on two real benchmark datasets, i.e., ACE and DALY, proves the efficiency and accuracy. PMID:25539847

  3. SNP and haplotype mapping for genetic analysis in the rat.

    PubMed

    Saar, Kathrin; Beck, Alfred; Bihoreau, Marie-Thérèse; Birney, Ewan; Brocklebank, Denise; Chen, Yuan; Cuppen, Edwin; Demonchy, Stephanie; Dopazo, Joaquin; Flicek, Paul; Foglio, Mario; Fujiyama, Asao; Gut, Ivo G; Gauguier, Dominique; Guigo, Roderic; Guryev, Victor; Heinig, Matthias; Hummel, Oliver; Jahn, Niels; Klages, Sven; Kren, Vladimir; Kube, Michael; Kuhl, Heiner; Kuramoto, Takashi; Kuroki, Yoko; Lechner, Doris; Lee, Young-Ae; Lopez-Bigas, Nuria; Lathrop, G Mark; Mashimo, Tomoji; Medina, Ignacio; Mott, Richard; Patone, Giannino; Perrier-Cornet, Jeanne-Antide; Platzer, Matthias; Pravenec, Michal; Reinhardt, Richard; Sakaki, Yoshiyuki; Schilhabel, Markus; Schulz, Herbert; Serikawa, Tadao; Shikhagaie, Medya; Tatsumoto, Shouji; Taudien, Stefan; Toyoda, Atsushi; Voigt, Birger; Zelenika, Diana; Zimdahl, Heike; Hubner, Norbert

    2008-05-01

    The laboratory rat is one of the most extensively studied model organisms. Inbred laboratory rat strains originated from limited Rattus norvegicus founder populations, and the inherited genetic variation provides an excellent resource for the correlation of genotype to phenotype. Here, we report a survey of genetic variation based on almost 3 million newly identified SNPs. We obtained accurate and complete genotypes for a subset of 20,238 SNPs across 167 distinct inbred rat strains, two rat recombinant inbred panels and an F2 intercross. Using 81% of these SNPs, we constructed high-density genetic maps, creating a large dataset of fully characterized SNPs for disease gene mapping. Our data characterize the population structure and illustrate the degree of linkage disequilibrium. We provide a detailed SNP map and demonstrate its utility for mapping of quantitative trait loci. This community resource is openly available and augments the genetic tools for this workhorse of physiological studies. PMID:18443594

  4. Sibship analysis of associations between SNP haplotypes and a continuous trait with application to mammographic density.

    PubMed

    Stone, J; Gurrin, L C; Hayes, V M; Southey, M C; Hopper, J L; Byrnes, G B

    2010-05-01

    Haplotype-based association studies have been proposed as a powerful comprehensive approach to identify causal genetic variation underlying complex diseases. Data comparisons within families offer the additional advantage of dealing naturally with complex sources of noise, confounding and population stratification. Two problems encountered when investigating associations between haplotypes and a continuous trait using data from sibships are (i) the need to define within-sibship comparisons for sibships of size greater than two and (ii) the difficulty of resolving the joint distribution of haplotype pairs within sibships in the absence of parental genotypes. We therefore propose first a method of orthogonal transformation of both outcomes and exposures that allow the decomposition of between- and within-sibship regression effects when sibship size is greater than two. We conducted a simulation study, which confirmed analysis using all members of a sibship is statistically more powerful than methods based on cross-sectional analysis or using subsets of sib-pairs. Second, we propose a simple permutation approach to avoid errors of inference due to the within-sibship correlation of any errors in haplotype assignment. These methods were applied to investigate the association between mammographic density (MD), a continuously distributed and heritable risk factor for breast cancer, and single nucleotide polymorphisms (SNPs) and haplotypes from the VDR gene using data from a study of 430 twins and sisters. We found evidence of association between MD and a 4-SNP VDR haplotype. In conclusion, our proposed method retains the benefits of the between- and within-pair analysis for pairs of siblings and can be implemented in standard software. PMID:19918759

  5. The Effect of Single-Nucleotide Polymorphism Marker Selection on Patterns of Haplotype Blocks and Haplotype Frequency Estimates

    PubMed Central

    Nothnagel, Michael; Rohde, Klaus

    2005-01-01

    The definition of haplotype blocks of single-nucleotide polymorphisms (SNPs) has been proposed so that the haplotypes can be used as markers in association studies and to efficiently describe human genetic variation. The International Haplotype Map (HapMap) project to construct a comprehensive catalog of haplotypic variation in humans is underway. However, a number of factors have already been shown to influence the definition of blocks, including the population studied and the sample SNP density. Here, we examine the effect that marker selection has on the definition of blocks and the pattern of haplotypes by using comparable but complementary SNP sets and a number of block definition methods in various genomic regions and populations that were provided by the Encyclopedia of DNA Elements (ENCODE) project. We find that the chosen SNP set has a profound effect on the block-covered sequence and block borders, even at high marker densities. Our results question the very concept of discrete haplotype blocks and the possibility of generalizing block findings from the HapMap project. We comparatively apply the block-free tagging-SNP approach and discuss both the haplotype approach and the tagging-SNP approach as means to efficiently catalog genetic variation. PMID:16380910

  6. Haplotype reconstruction and estimation of haplotype frequencies from nuclear families with only one parent available.

    PubMed

    Ding, Xiangdong; Zhang, Qin; Flury, Christine; Simianer, Henner

    2006-01-01

    Recent literature has suggested that haplotype inference through close relatives, especially from nuclear families can be an alternative strategy in determining the linkage phase. In this paper, haplotype reconstruction and estimation of haplotype frequencies via expectation maximization (EM) algorithm including nuclear families with only one parent available is proposed. Parent and his (her) child are treated as parent-child pair with one shared haplotype. This reduces the number of potential haplotype pairs for both parent and child separately, resulting in a higher accuracy of the estimation. In a series of simulations, the comparisons of PHASE, GENEHUNTER, EM-based approach for complete nuclear families and our approach are carried out. In all situations, EM-based approach for trio data is comparable but slightly worse error rate than PHASE, our approach is slightly better and much faster than PHASE for incomplete trios, the performance of GENEHUNTER is very bad in simple nuclear family settings and dramatically decreased with the number of markers being increased. On the other hand, the comparison result of different sampling designs demonstrates that sampling trios is the most efficient design to estimate haplotype frequencies in populations under same genotyping cost. PMID:16954697

  7. Multi-SNP analysis of MHC region: remarkable conservation of HLA-A1-B8-DR3 haplotype.

    PubMed

    Aly, Theresa A; Eller, Elise; Ide, Akane; Gowan, Katherine; Babu, Sunanda R; Erlich, Henry A; Rewers, Marian J; Eisenbarth, George S; Fain, Pamela R

    2006-05-01

    Technology has become available to cost-effectively analyze thousands of single nucleotide polymorphisms (SNPs). We recently confirmed by genotyping a small series of class I alleles and microsatellite markers that the extended haplotype HLA-A1-B8-DR3 (8.1 AH) at the major histocompatibility complex (MHC) is a common and conserved haplotype. To further evaluate the region of conservation of the DR3 haplotypes, we genotyped 31 8.1 AHs and 29 other DR3 haplotypes with a panel of 656 SNPs spanning 4.8 Mb in the MHC region. This multi-SNP evaluation revealed a 2.9-Mb region that was essentially invariable for all 31 8.1 AHs. The 31 8.1 AHs were >99.9% identical for 384 consecutive SNPs of the 656 SNPs analyzed. Future association studies of MHC-linked susceptibility to type 1 diabetes will need to account for the extensive conservation of the 8.1 AH, since individuals who carry this haplotype provide no information about the differential effects of the alleles that are present on this haplotype. PMID:16644681

  8. [Genetic Variability and Structure of SNP Haplotypes in the DMPK Gene in Yakuts and Other Ethnic Groups of Northern Eurasia in Relation to Myotonic Dystrophy].

    PubMed

    Swarovskaya, M G; Stepanova, S K; Marussin, A V; Sukhomyasova, A L; Maximova, N R; Stepanov, V A

    2015-06-01

    The genetic variability of the DMPK locus has been studied in relation to six SNP markers (rs2070736, rs572634, rs1799894, rs527221, rs915915, and rs10415988) in Yakuts with myotonic dystrophy (MD) in the Yakut population and in populations of northern Eurasia. Significant differences were observed in the allele frequencies between patients and a population sample of Yakuts for three SNP loci (rs915915, rs1799894, and rs10415988) associated with a high chance of disease manifestation. The odds ratios (OR) of MD development in representatives of the Yakut population for these three loci were 2.59 (95% CI, p = 0,004), 4.99 (95% CI, p = 0.000), and 3.15 (95% CI, p = 0.01), respectively. Haplotype TTTCTC, which is associated with MD, and haplotype GTCCTT, which was observed only in Yakut MD patients (never in MD patients of non-Yakut origin), were revealed. A low level of variability in the locus of DMRK gene in Yakuts (H(e) = 0.283) compared with other examined populations was noted. An analysis of pairwise genetic relationships between populations revealed their significant differentiation for all the examined loci. In addition, a low level of differentiation in territorial groups of Yakut populations (F(ST) = 0.79%), which was related to the high subdivision of the northern Eurasian population (F(ST) = 11.83%), was observed. PMID:26310035

  9. HLA Haplotypes and Genotypes Frequencies in Brazilian Chronic Periodontitis Patients

    PubMed Central

    Sippert, Emília Ângela; Silva, Cléverson de Oliveira e; Ayo, Christiane Maria; Marques, Silvia Barbosa Dutra; Visentainer, Jeane Eliete Laguila; Sell, Ana Maria

    2015-01-01

    Human leukocyte antigens (HLA) have a pivotal role in immune response and may be involved in antigen recognition of periodontal pathogens. However, the associations of HLA with chronic periodontitis (CP) have not been previously studied in the Brazilian population. In an attempt to clarify the issue of genetic predisposition to CP, we examined the distribution of HLA alleles, genotypes, and haplotypes in patients from Southern Brazil. One hundred and eight CP patients and 151 healthy and unrelated controls with age-, gender-, and ethnicity-matched were HLA investigated by polymerase chain reaction with sequence specific oligonucleotides. To exclude smoking as a predisposing factor, statistical analyses were performed in the total sample and in nonsmoking individuals. The significant results showed a positive association of the A∗02/HLA-B∗40 haplotype with CP (total samples: 4.2% versus 0%, Pc = 0.03; nonsmokers: 4.3% versus 0%, Pc = 0.23) and a lower frequency of HLA-B∗15/HLA-DRB1∗11 haplotype in CP compared to controls (total samples: 0.0% versus 4.3%, Pc = 0.04; nonsmokers: 0 versus 5.1%, Pc = 1.0). In conclusion, the HLA-A∗02/B∗40 haplotype may contribute to the development of CP, while HLA-B∗15/DRB1∗11 haplotype might indicate resistance to disease among Brazilians. PMID:26339134

  10. A combined long-range phasing and long haplotype imputation method to impute phase for SNP genotypes

    PubMed Central

    2011-01-01

    Background Knowing the phase of marker genotype data can be useful in genome-wide association studies, because it makes it possible to use analysis frameworks that account for identity by descent or parent of origin of alleles and it can lead to a large increase in data quantities via genotype or sequence imputation. Long-range phasing and haplotype library imputation constitute a fast and accurate method to impute phase for SNP data. Methods A long-range phasing and haplotype library imputation algorithm was developed. It combines information from surrogate parents and long haplotypes to resolve phase in a manner that is not dependent on the family structure of a dataset or on the presence of pedigree information. Results The algorithm performed well in both simulated and real livestock and human datasets in terms of both phasing accuracy and computation efficiency. The percentage of alleles that could be phased in both simulated and real datasets of varying size generally exceeded 98% while the percentage of alleles incorrectly phased in simulated data was generally less than 0.5%. The accuracy of phasing was affected by dataset size, with lower accuracy for dataset sizes less than 1000, but was not affected by effective population size, family data structure, presence or absence of pedigree information, and SNP density. The method was computationally fast. In comparison to a commonly used statistical method (fastPHASE), the current method made about 8% less phasing mistakes and ran about 26 times faster for a small dataset. For larger datasets, the differences in computational time are expected to be even greater. A computer program implementing these methods has been made available. Conclusions The algorithm and software developed in this study make feasible the routine phasing of high-density SNP chips in large datasets. PMID:21388557

  11. Maximum likelihood model based on minor allele frequencies and weighted Max-SAT formulation for haplotype assembly.

    PubMed

    Mousavi, Sayyed R; Khodadadi, Ilnaz; Falsafain, Hossein; Nadimi, Reza; Ghadiri, Nasser

    2014-06-01

    Human haplotypes include essential information about SNPs, which in turn provide valuable information for such studies as finding relationships between some diseases and their potential genetic causes, e.g., for Genome Wide Association Studies. Due to expensiveness of directly determining haplotypes and recent progress in high throughput sequencing, there has been an increasing motivation for haplotype assembly, which is the problem of finding a pair of haplotypes from a set of aligned fragments. Although the problem has been extensively studied and a number of algorithms have already been proposed for the problem, more accurate methods are still beneficial because of high importance of the haplotypes information. In this paper, first, we develop a probabilistic model, that incorporates the Minor Allele Frequency (MAF) of SNP sites, which is missed in the existing maximum likelihood models. Then, we show that the probabilistic model will reduce to the Minimum Error Correction (MEC) model when the information of MAF is omitted and some approximations are made. This result provides a novel theoretical support for the MEC, despite some criticisms against it in the recent literature. Next, under the same approximations, we simplify the model to an extension of the MEC in which the information of MAF is used. Finally, we extend the haplotype assembly algorithm HapSAT by developing a weighted Max-SAT formulation for the simplified model, which is evaluated empirically with positive results. PMID:24491253

  12. Genomic-assisted haplotype analysis and the development of high-throughput SNP markers for salinity tolerance in soybean

    PubMed Central

    Patil, Gunvant; Do, Tuyen; Vuong, Tri D.; Valliyodan, Babu; Lee, Jeong-Dong; Chaudhary, Juhi; Shannon, J. Grover; Nguyen, Henry T.

    2016-01-01

    Soil salinity is a limiting factor of crop yield. The soybean is sensitive to soil salinity, and a dominant gene, Glyma03g32900 is primarily responsible for salt-tolerance. The identification of high throughput and robust markers as well as the deployment of salt-tolerant cultivars are effective approaches to minimize yield loss under saline conditions. We utilized high quality (15x) whole-genome resequencing (WGRS) on 106 diverse soybean lines and identified three major structural variants and allelic variation in the promoter and genic regions of the GmCHX1 gene. The discovery of single nucleotide polymorphisms (SNPs) associated with structural variants facilitated the design of six KASPar assays. Additionally, haplotype analysis and pedigree tracking of 93 U.S. ancestral lines were performed using publically available WGRS datasets. Identified SNP markers were validated, and a strong correlation was observed between the genotype and salt treatment phenotype (leaf scorch, chlorophyll content and Na+ accumulation) using a panel of 104 soybean lines and, an interspecific bi-parental population (F8) from PI483463 x Hutcheson. These markers precisely identified salt-tolerant/sensitive genotypes (>91%), and different structural-variants (>98%). These SNP assays, supported by accurate phenotyping, haplotype analyses and pedigree tracking information, will accelerate marker-assisted selection programs to enhance the development of salt-tolerant soybean cultivars. PMID:26781337

  13. Identification of SNP Haplotypes and Prospects of Association Mapping in Watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon is the fifth most economically important vegetable crop cultivated world-wide. Implementing Single Nucleotide Polymorphism (SNP) marker technology in watermelon breeding and germplasm evaluation programs holds a key to improve horticulturally important traits. Next-generation sequencing...

  14. Alternative haplotype construction methods for genomic evaluation.

    PubMed

    Jónás, Dávid; Ducrocq, Vincent; Fouilloux, Marie-Noëlle; Croiseau, Pascal

    2016-06-01

    Genomic evaluation methods today use single nucleotide polymorphism (SNP) as genomic markers to trace quantitative trait loci (QTL). Today most genomic prediction procedures use biallelic SNP markers. However, SNP can be combined into short, multiallelic haplotypes that can improve genomic prediction due to higher linkage disequilibrium between the haplotypes and the linked QTL. The aim of this study was to develop a method to identify the haplotypes, which can be expected to be superior in genomic evaluation, as compared with either SNP or other haplotypes of the same size. We first identified the SNP (termed as QTL-SNP) from the bovine 50K SNP chip that had the largest effect on the analyzed trait. It was assumed that these SNP were not the causative mutations and they merely indicated the approximate location of the QTL. Haplotypes of 3, 4, or 5 SNP were selected from short genomic windows surrounding these markers to capture the effect of the QTL. Two methods described in this paper aim at selecting the most optimal haplotype for genomic evaluation. They assumed that if an allele has a high frequency, its allele effect can be accurately predicted. These methods were tested in a classical validation study using a dairy cattle population of 2,235 bulls with genotypes from the bovine 50K SNP chip and daughter yield deviations (DYD) on 5 dairy cattle production traits. Combining the SNP into haplotypes was beneficial with all tested haplotypes, leading to an average increase of 2% in terms of correlations between DYD and genomic breeding value estimates compared with the analysis when the same SNP were used individually. Compared with haplotypes built by merging the QTL-SNP with its flanking SNP, the haplotypes selected with the proposed criteria carried less under- and over-represented alleles: the proportion of alleles with frequencies <1 or >40% decreased, on average, by 17.4 and 43.4%, respectively. The correlations between DYD and genomic breeding value

  15. Global patterns of variation in allele and haplotype frequencies and linkage disequilibrium across the CYP2E1 gene

    PubMed Central

    Lee, Mi-Young; Mukherjee, Namita; Pakstis, Andrew J.; Khaliq, Shagufta; Mohyuddin, Aisha; Mehdi, S. Qasim; Speed, William C.; Kidd, Judith R.; Kidd, Kenneth K.

    2009-01-01

    Cytochrome P450 2E1, gene symbol CYP2E1, is one of a family of enzymes with a central role in activating and detoxifying xenobiotics and endogenous compounds. Genetic variation at this gene has been reported in different human populations, and some association studies have reported increased risk for cancers and other diseases. To the best of our knowledge, multi-SNP haplotypes and linkage disequilibrium (LD) have not been systematically studied for CYP2E1 in multiple populations. Haplotypes can greatly increase the power both to identify patterns of genetic variation relevant for gene expression as well as to detect disease-related susceptibility mutations. We present frequency and LD data and analyses for 11 polymorphisms and their haplotypes that we have studied on over 2,600 individuals from 50 human population samples representing the major geographical regions of the world. The diverse patterns of haplotype variation found in the different populations we have studied show that ethnicity may be an important variable helping to explain inconsistencies that have been reported by association studies. More studies clearly are needed of the variants we have studied, especially those in the 5′ region, such as the VNTR, as well as studies of additional polymorphisms known for this gene to establish evidence relating any systematic differences in gene expression that exist to the haplotypes at this gene. PMID:18663376

  16. SNP analyses of growth factor genes EGF, TGF{beta}-1, and HGF reveal haplotypic association of EGF with autism

    SciTech Connect

    Toyoda, Takao; Thanseem, Ismail; Kawai, Masayoshi; Sekine, Yoshimoto; Nakamura, Kazuhiko; Anitha, Ayyappan; Suda, Shiro . E-mail: nakamura@hama-med.ac.jp; Yamada, Kazuo; Tsujii, Masatsugu |; Iwayama, Yoshimi; Hattori, Eiji; Toyota, Tomoko; Yoshikawa, Takeo; Miyachi, Taishi; Tsuchiya, Kenji; Sugihara, Gen-ichi; Matsuzaki, Hideo; Iwata, Yasuhide; Suzuki, Katsuaki; Mori, Norio |; Ouchi, Yasuomi |; Sugiyama, Toshiro; Takei, Nori

    2007-09-07

    Autism is a pervasive neurodevelopmental disorder diagnosed in early childhood. Growth factors have been found to play a key role in the cellular differentiation and proliferation of the central and peripheral nervous systems. Epidermal growth factor (EGF) is detected in several regions of the developing and adult brain, where, it enhances the differentiation, maturation, and survival of a variety of neurons. Transforming growth factor-{beta} (TGF{beta}) isoforms play an important role in neuronal survival, and the hepatocyte growth factor (HGF) has been shown to exhibit neurotrophic activity. We examined the association of EGF, TGF{beta}1, and HGF genes with autism, in a trio association study, using DNA samples from families recruited to the Autism Genetic Resource Exchange; 252 trios with a male offspring scored for autism were selected for the study. Transmission disequilibrium test revealed significant haplotypic association of EGF with autism. No significant SNP or haplotypic associations were observed for TGF{beta}1 or HGF. Given the role of EGF in brain and neuronal development, we suggest a possible role of EGF in the pathogenesis of autism.

  17. Haplotype block partitioning as a tool for dimensionality reduction in SNP association studies

    PubMed Central

    Pattaro, Cristian; Ruczinski, Ingo; Fallin, Danièle M; Parmigiani, Giovanni

    2008-01-01

    Background Identification of disease-related genes in association studies is challenged by the large number of SNPs typed. To address the dilution of power caused by high dimensionality, and to generate results that are biologically interpretable, it is critical to take into consideration spatial correlation of SNPs along the genome. With the goal of identifying true genetic associations, partitioning the genome according to spatial correlation can be a powerful and meaningful way to address this dimensionality problem. Results We developed and validated an MCMC Algorithm To Identify blocks of Linkage DisEquilibrium (MATILDE) for clustering contiguous SNPs, and a statistical testing framework to detect association using partitions as units of analysis. We compared its ability to detect true SNP associations to that of the most commonly used algorithm for block partitioning, as implemented in the Haploview and HapBlock software. Simulations were based on artificially assigning phenotypes to individuals with SNPs corresponding to region 14q11 of the HapMap database. When block partitioning is performed using MATILDE, the ability to correctly identify a disease SNP is higher, especially for small effects, than it is with the alternatives considered. Advantages can be both in terms of true positive findings and limiting the number of false discoveries. Finer partitions provided by LD-based methods or by marker-by-marker analysis are efficient only for detecting big effects, or in presence of large sample sizes. The probabilistic approach we propose offers several additional advantages, including: a) adapting the estimation of blocks to the population, technology, and sample size of the study; b) probabilistic assessment of uncertainty about block boundaries and about whether any two SNPs are in the same block; c) user selection of the probability threshold for assigning SNPs to the same block. Conclusion We demonstrate that, in realistic scenarios, our adaptive, study

  18. Ehapp2: Estimate haplotype frequencies from pooled sequencing data with prior database information.

    PubMed

    Cao, Chang-Chang; Sun, Xiao

    2016-08-01

    To reduce the cost of large-scale re-sequencing, multiple individuals are pooled together and sequenced called pooled sequencing. Pooled sequencing could provide a cost-effective alternative to sequencing individuals separately. To facilitate the application of pooled sequencing in haplotype-based diseases association analysis, the critical procedure is to accurately estimate haplotype frequencies from pooled samples. Here we present Ehapp2 for estimating haplotype frequencies from pooled sequencing data by utilizing a database which provides prior information of known haplotypes. We first translate the problem of estimating frequency for each haplotype into finding a sparse solution for a system of linear equations, where the NNREG algorithm is employed to achieve the solution. Simulation experiments reveal that Ehapp2 is robust to sequencing errors and able to estimate the frequencies of haplotypes with less than 3% average relative difference for pooled sequencing of mixture of real Drosophila haplotypes with 50× total coverage even when the sequencing error rate is as high as 0.05. Owing to the strategy that proportions for local haplotypes spanning multiple SNPs are accurately calculated first, Ehapp2 retains excellent estimation for recombinant haplotypes resulting from chromosomal crossover. Comparisons with present methods reveal that Ehapp2 is state-of-the-art for many sequencing study designs and more suitable for current massive parallel sequencing. PMID:27216711

  19. SNP-VISTA

    SciTech Connect

    Shah, Nameeta; Teplitsky, Michael; Minovitsky, Simon; Dubchak, Inna

    2005-11-07

    SNP-VISTA aids in analyses of the following types of data: A. Large-scale re-sequence data of disease-related genes for discovery of associated and/or causative alleles (GeneSNP-VISTA). B. Massive amounts of ecogenomics data for studying homologous recombination in microbial populations (EcoSNP-VISTA). The main features and capabilities of SNP-VISTA are: 1) Mapping of SNPs to gene structure; 2) classification of SNPs, based on their location in the gene, frequency of occurrence in samples and allele composition; 3) clustering, based on user-defined subsets of SNPs, highlighting haplotypes as well as recombinant sequences; 4) integration of protein conservation visualization; and 5) display of automatically calculated recombination points that are user-editable. The main strength of SNP-VISTA is its graphical interface and use of visual representations, which support interactive exploration and hence better understanding of large-scale SNPs data.

  20. Frequency-based haplotype reconstruction from deep sequencing data of bacterial populations

    PubMed Central

    Pulido-Tamayo, Sergio; Sánchez-Rodríguez, Aminael; Swings, Toon; Van den Bergh, Bram; Dubey, Akanksha; Steenackers, Hans; Michiels, Jan; Fostier, Jan; Marchal, Kathleen

    2015-01-01

    Clonal populations accumulate mutations over time, resulting in different haplotypes. Deep sequencing of such a population in principle provides information to reconstruct these haplotypes and the frequency at which the haplotypes occur. However, this reconstruction is technically not trivial, especially not in clonal systems with a relatively low mutation frequency. The low number of segregating sites in those systems adds ambiguity to the haplotype phasing and thus obviates the reconstruction of genome-wide haplotypes based on sequence overlap information. Therefore, we present EVORhA, a haplotype reconstruction method that complements phasing information in the non-empty read overlap with the frequency estimations of inferred local haplotypes. As was shown with simulated data, as soon as read lengths and/or mutation rates become restrictive for state-of-the-art methods, the use of this additional frequency information allows EVORhA to still reliably reconstruct genome-wide haplotypes. On real data, we show the applicability of the method in reconstructing the population composition of evolved bacterial populations and in decomposing mixed bacterial infections from clinical samples. PMID:25990729

  1. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits

    PubMed Central

    Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca e; Mundim, Gabriel Borges

    2016-01-01

    Abstract The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis. PMID:27007903

  2. Linkage disequilibrium, SNP frequency change due to selection, and association mapping in popcorn chromosome regions containing QTLs for quality traits.

    PubMed

    Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca E; Mundim, Gabriel Borges

    2016-03-01

    The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis. PMID:27007903

  3. Improved imputation of low-frequency and rare variants using the UK10K haplotype reference panel

    PubMed Central

    Huang, Jie; Howie, Bryan; McCarthy, Shane; Memari, Yasin; Walter, Klaudia; Min, Josine L.; Danecek, Petr; Malerba, Giovanni; Trabetti, Elisabetta; Zheng, Hou-Feng; Al Turki, Saeed; Amuzu, Antoinette; Anderson, Carl A.; Anney, Richard; Antony, Dinu; Artigas, María Soler; Ayub, Muhammad; Bala, Senduran; Barrett, Jeffrey C.; Barroso, Inês; Beales, Phil; Benn, Marianne; Bentham, Jamie; Bhattacharya, Shoumo; Birney, Ewan; Blackwood, Douglas; Bobrow, Martin; Bochukova, Elena; Bolton, Patrick F.; Bounds, Rebecca; Boustred, Chris; Breen, Gerome; Calissano, Mattia; Carss, Keren; Pablo Casas, Juan; Chambers, John C.; Charlton, Ruth; Chatterjee, Krishna; Chen, Lu; Ciampi, Antonio; Cirak, Sebahattin; Clapham, Peter; Clement, Gail; Coates, Guy; Cocca, Massimiliano; Collier, David A.; Cosgrove, Catherine; Cox, Tony; Craddock, Nick; Crooks, Lucy; Curran, Sarah; Curtis, David; Daly, Allan; Day, Ian N. M.; Day-Williams, Aaron; Dedoussis, George; Down, Thomas; Du, Yuanping; van Duijn, Cornelia M.; Dunham, Ian; Edkins, Sarah; Ekong, Rosemary; Ellis, Peter; Evans, David M.; Farooqi, I. Sadaf; Fitzpatrick, David R.; Flicek, Paul; Floyd, James; Foley, A. Reghan; Franklin, Christopher S.; Futema, Marta; Gallagher, Louise; Gasparini, Paolo; Gaunt, Tom R.; Geihs, Matthias; Geschwind, Daniel; Greenwood, Celia; Griffin, Heather; Grozeva, Detelina; Guo, Xiaosen; Guo, Xueqin; Gurling, Hugh; Hart, Deborah; Hendricks, Audrey E.; Holmans, Peter; Huang, Liren; Hubbard, Tim; Humphries, Steve E.; Hurles, Matthew E.; Hysi, Pirro; Iotchkova, Valentina; Isaacs, Aaron; Jackson, David K.; Jamshidi, Yalda; Johnson, Jon; Joyce, Chris; Karczewski, Konrad J.; Kaye, Jane; Keane, Thomas; Kemp, John P.; Kennedy, Karen; Kent, Alastair; Keogh, Julia; Khawaja, Farrah; Kleber, Marcus E.; van Kogelenberg, Margriet; Kolb-Kokocinski, Anja; Kooner, Jaspal S.; Lachance, Genevieve; Langenberg, Claudia; Langford, Cordelia; Lawson, Daniel; Lee, Irene; van Leeuwen, Elisabeth M.; Lek, Monkol; Li, Rui; Li, Yingrui; Liang, Jieqin; Lin, Hong; Liu, Ryan; Lönnqvist, Jouko; Lopes, Luis R.; Lopes, Margarida; Luan, Jian'an; MacArthur, Daniel G.; Mangino, Massimo; Marenne, Gaëlle; März, Winfried; Maslen, John; Matchan, Angela; Mathieson, Iain; McGuffin, Peter; McIntosh, Andrew M.; McKechanie, Andrew G.; McQuillin, Andrew; Metrustry, Sarah; Migone, Nicola; Mitchison, Hannah M.; Moayyeri, Alireza; Morris, James; Morris, Richard; Muddyman, Dawn; Muntoni, Francesco; Nordestgaard, Børge G.; Northstone, Kate; O'Donovan, Michael C.; O'Rahilly, Stephen; Onoufriadis, Alexandros; Oualkacha, Karim; Owen, Michael J.; Palotie, Aarno; Panoutsopoulou, Kalliope; Parker, Victoria; Parr, Jeremy R.; Paternoster, Lavinia; Paunio, Tiina; Payne, Felicity; Payne, Stewart J.; Perry, John R. B.; Pietilainen, Olli; Plagnol, Vincent; Pollitt, Rebecca C.; Povey, Sue; Quail, Michael A.; Quaye, Lydia; Raymond, Lucy; Rehnström, Karola; Ridout, Cheryl K.; Ring, Susan; Ritchie, Graham R. S.; Roberts, Nicola; Robinson, Rachel L.; Savage, David B.; Scambler, Peter; Schiffels, Stephan; Schmidts, Miriam; Schoenmakers, Nadia; Scott, Richard H.; Scott, Robert A.; Semple, Robert K.; Serra, Eva; Sharp, Sally I.; Shaw, Adam; Shihab, Hashem A.; Shin, So-Youn; Skuse, David; Small, Kerrin S.; Smee, Carol; Smith, George Davey; Southam, Lorraine; Spasic-Boskovic, Olivera; Spector, Timothy D.; St Clair, David; St Pourcain, Beate; Stalker, Jim; Stevens, Elizabeth; Sun, Jianping; Surdulescu, Gabriela; Suvisaari, Jaana; Syrris, Petros; Tachmazidou, Ioanna; Taylor, Rohan; Tian, Jing; Tobin, Martin D.; Toniolo, Daniela; Traglia, Michela; Tybjaerg-Hansen, Anne; Valdes, Ana M.; Vandersteen, Anthony M.; Varbo, Anette; Vijayarangakannan, Parthiban; Visscher, Peter M.; Wain, Louise V.; Walters, James T. R.; Wang, Guangbiao; Wang, Jun; Wang, Yu; Ward, Kirsten; Wheeler, Eleanor; Whincup, Peter; Whyte, Tamieka; Williams, Hywel J.; Williamson, Kathleen A.; Wilson, Crispian; Wilson, Scott G.; Wong, Kim; Xu, ChangJiang; Yang, Jian; Zaza, Gianluigi; Zeggini, Eleftheria; Zhang, Feng; Zhang, Pingbo; Zhang, Weihua; Gambaro, Giovanni; Richards, J. Brent; Durbin, Richard; Timpson, Nicholas J.; Marchini, Jonathan; Soranzo, Nicole

    2015-01-01

    Imputing genotypes from reference panels created by whole-genome sequencing (WGS) provides a cost-effective strategy for augmenting the single-nucleotide polymorphism (SNP) content of genome-wide arrays. The UK10K Cohorts project has generated a data set of 3,781 whole genomes sequenced at low depth (average 7x), aiming to exhaustively characterize genetic variation down to 0.1% minor allele frequency in the British population. Here we demonstrate the value of this resource for improving imputation accuracy at rare and low-frequency variants in both a UK and an Italian population. We show that large increases in imputation accuracy can be achieved by re-phasing WGS reference panels after initial genotype calling. We also present a method for combining WGS panels to improve variant coverage and downstream imputation accuracy, which we illustrate by integrating 7,562 WGS haplotypes from the UK10K project with 2,184 haplotypes from the 1000 Genomes Project. Finally, we introduce a novel approximation that maintains speed without sacrificing imputation accuracy for rare variants. PMID:26368830

  4. Improved imputation of low-frequency and rare variants using the UK10K haplotype reference panel.

    PubMed

    Huang, Jie; Howie, Bryan; McCarthy, Shane; Memari, Yasin; Walter, Klaudia; Min, Josine L; Danecek, Petr; Malerba, Giovanni; Trabetti, Elisabetta; Zheng, Hou-Feng; Gambaro, Giovanni; Richards, J Brent; Durbin, Richard; Timpson, Nicholas J; Marchini, Jonathan; Soranzo, Nicole

    2015-01-01

    Imputing genotypes from reference panels created by whole-genome sequencing (WGS) provides a cost-effective strategy for augmenting the single-nucleotide polymorphism (SNP) content of genome-wide arrays. The UK10K Cohorts project has generated a data set of 3,781 whole genomes sequenced at low depth (average 7x), aiming to exhaustively characterize genetic variation down to 0.1% minor allele frequency in the British population. Here we demonstrate the value of this resource for improving imputation accuracy at rare and low-frequency variants in both a UK and an Italian population. We show that large increases in imputation accuracy can be achieved by re-phasing WGS reference panels after initial genotype calling. We also present a method for combining WGS panels to improve variant coverage and downstream imputation accuracy, which we illustrate by integrating 7,562 WGS haplotypes from the UK10K project with 2,184 haplotypes from the 1000 Genomes Project. Finally, we introduce a novel approximation that maintains speed without sacrificing imputation accuracy for rare variants. PMID:26368830

  5. Haplotype Frequency Distribution in Northeastern European Saduria entomon (Crustacea: Isopoda) Populations. A Phylogeographic Approach

    NASA Astrophysics Data System (ADS)

    Sell, Jerzy

    2003-11-01

    The distribution pattern of mtDNA haplotypes in distinct populations of the glacial relict crustacean Saduria entomon was examined to assess phylogeographic relationships among them. Populations from the Baltic, the White Sea and the Barents Sea were screened for mtDNA variation using PCR-based RFLP analysis of a 1150 bp fragment containing part of the CO I and CO II genes. Five mtDNA haplotypes were recorded. An analysis of geographical heterogeneity in haplotype frequency distributions revealed significant differences among populations. The isolated populations of S. entomon have diverged since the retreat of the last glaciation. The geographical pattern of variation is most likely the result of stochastic (founder effect, genetic drift) mechanisms and suggests that the haplotype differentiation observed is probably older than the isolation of the Baltic and Arctic seas.

  6. Frequency of carriers of 8.1 ancestral haplotype and its fragments in two Caucasian populations.

    PubMed

    Kiszel, Petra; Kovács, Margit; Szalai, Csaba; Yang, Yan; Pozsonyi, Eva; Blaskó, Bernadett; Laki, Judit; Prohászka, Zoltán; Fazakas, Adám; Pánczél, Pál; Hosszúfalusi, Nóra; Rajczy, Katalin; Wu, Yee-Ling; Chung, Erwin K; Zhou, Bi; Blanchong, Carol A; Vatay, Agnes; Yu, C Yung; Füst, G

    2007-01-01

    Within the human MHC region larger stretches of conserved DNA, called conserved ancestral haplotypes exist. However, many MHC haplotypes contain only fragments of an ancestral haplotype. Little is known, however, on relative distribution of the ancestral haplotypes to their fragments. Therefore we determined the frequency of carriers of the whole ancestral haplotype 8.1 (AH8.1) and its fragments in 127 healthy Hungarian people, 101 healthy Ohioian females, and in nine Hungarian families. The HLA-DQ2, HLA-DR3(17), RAGE -429C allele, the mono-S-C4B genotype, the HSP70-2 1267G allele and the TNF -308A (TNF2) allele were used as markers of the AH8.1. Frequency of carriers of the whole AH8.1 and its fragments was similar in the both populations. 18% of the subjects carried the whole AH8.1 in at least one chromosome, while 17-20%, 36-39%, and 24-29%, respectively carried two or three constituents of the haplotype, only one constituent or none of them. Similar results were obtained in the family study. In addition, marked differences were found in the relationship of the constituents' alleles to the whole AH8.1. In both populations, 29%, 50-59%, 52-56% and 76-96%, respectively of the carriers of HSP70-2 1267G, RAGE-429C, TNF2, and mono-S carriers carried the whole 8.1 haplotype. These findings may have important implications for studies of the disease associations with different MHC ancestral haplotypes. PMID:17558713

  7. Mitochondrial DNA haplotype frequencies in natural and experimental populations of Drosophila subobscura.

    PubMed Central

    García-Martínez, J; Castro, J A; Ramón, M; Latorre, A; Moya, A

    1998-01-01

    The evolution of Drosophila subobscura mitochondrial DNA has been studied in experimental populations, founded with flies from a natural population from Esporles (Majorca, Balearic Islands, Spain). This population, like other European ones, is characterized by the presence of two very common (>96%) mitochondrial haplotypes (called I and II) and rare and endemic haplotypes that appear at very low frequencies. There is no statistical evidence of positive Darwinian selection acting on the mitochondrial DNA variants according to Tajima's neutrality test. Two experimental populations, with one replicate each, were established with flies having a heterogeneous nuclear genetic background, which was representative of the composition of the natural population. Both populations were started with the two most frequent mitochondrial haplotypes, but at different initial frequencies. After 13 to 16 generations, haplotype II reached fixation in three cages and its frequency was 0.89 by generation 25 in the fourth cage. Random drift can be rejected as the force responsible for the observed changes in haplotype frequencies. There is not only statistical evidence of a linear trend favoring a mtDNA (haploid) fitness effect, but also of a significant nonlinear deviation that could be due to a nuclear component. PMID:9649527

  8. Frequencies of single-nucleotide polymorphisms and haplotypes of the SLCO1B1 gene in selected populations of the western balkans.

    PubMed

    Grapci, A Daka; Dimovski, A J; Kapedanovska, A; Vavlukis, M; Eftimov, A; Geshkovska, N Matevska; Labachevski, N; Jakjovski, K; Gorani, D; Kedev, S; Mladenovska, K

    2015-06-01

    As a membrane influx transporter, organic anion-transporting polypeptide 1B1 (OATP1B1) regulates the cellular uptake of a number of endogenous compounds and drugs. The aim of this study was to characterize the diversity of the solute carrier organic anion transporter family member 1B1 (SLCO1B1) gene encoding this transporter in two ethnic groups populating the Western Balkans. The distribution of SCLO1B1 alleles was determined at seven variant sites (c.388A>G, c.521T>C, c.571T>C, c.597C>T, c.1086C>T, c.1463G>C and c.*439T>G) in 266 Macedonians and 94 Albanians using the TaqMan allelic discrimination assay. No significant difference in the frequencies of the single nucleotide polymorphisms (SNPs) was observed between these populations. The frequency of the c.521T>C SNP was the lowest (<13.7 and 12.2%, respectively), while the frequencies of all other SNP alleles were above 40.0%. Variant alleles of c.1463G>C and c.1086 C>T SNPs were not identified in either ethnic group. The haplotype analysis revealed 20 and 21 different haplotypes in the Macedonian and Albanian population, respectively. The most common haplotype in both ethnic groups, *1J/*1K/*1L, had a frequency of 39.0% and 26.6%, respectively. In both populations, the variant alleles of the functionally significant c.521T>C and c.388A>G SNPs existed in one major haplotype (*15/*16/*17), with a frequency of 8.6 and 2.4% in the Macedonian and Albanian subjects, respectively. In conclusion, sequence variations of the SLCO1B1 gene in the studied populations occur at high frequencies, which are similar to that of the Caucasian population. Further studies are needed to evaluate the clinical significance of these SNPs and/ or the major SLCO1B1 haplotypes they form for a large number of substrates and for susceptibility to certain diseases. PMID:26929901

  9. Frequencies of single-nucleotide polymorphisms and haplotypes of the SLCO1B1 gene in selected populations of the western balkans

    PubMed Central

    Grapci, A Daka; Dimovski, AJ; Kapedanovska, A; Vavlukis, M; Eftimov, A; Geshkovska, N Matevska; Labachevski, N; Jakjovski, K; Gorani, D; Kedev, S; Mladenovska, K

    2015-01-01

    As a membrane influx transporter, organic anion-transporting polypeptide 1B1 (OATP1B1) regulates the cellular uptake of a number of endogenous compounds and drugs. The aim of this study was to characterize the diversity of the solute carrier organic anion transporter family member 1B1 (SLCO1B1) gene encoding this transporter in two ethnic groups populating the Western Balkans. The distribution of SCLO1B1 alleles was determined at seven variant sites (c.388A>G, c.521T>C, c.571T>C, c.597C>T, c.1086C>T, c.1463G>C and c.*439T>G) in 266 Macedonians and 94 Albanians using the TaqMan allelic discrimination assay. No significant difference in the frequencies of the single nucleotide polymorphisms (SNPs) was observed between these populations. The frequency of the c.521T>C SNP was the lowest (<13.7 and 12.2%, respectively), while the frequencies of all other SNP alleles were above 40.0%. Variant alleles of c.1463G>C and c.1086 C>T SNPs were not identified in either ethnic group. The haplotype analysis revealed 20 and 21 different haplotypes in the Macedonian and Albanian population, respectively. The most common haplotype in both ethnic groups, *1J/*1K/*1L, had a frequency of 39.0% and 26.6%, respectively. In both populations, the variant alleles of the functionally significant c.521T>C and c.388A>G SNPs existed in one major haplotype (*15/*16/*17), with a frequency of 8.6 and 2.4% in the Macedonian and Albanian subjects, respectively. In conclusion, sequence variations of the SLCO1B1 gene in the studied populations occur at high frequencies, which are similar to that of the Caucasian population. Further studies are needed to evaluate the clinical significance of these SNPs and/ or the major SLCO1B1 haplotypes they form for a large number of substrates and for susceptibility to certain diseases. PMID:26929901

  10. Localization of Type 1 Diabetes susceptibility in the ancestral haplotype 18.2 by high density SNP mapping.

    PubMed

    Santiago, Jose Luis; Li, Wentian; Lee, Annette; Martinez, Alfonso; Chandrasekaran, Alamelu; Fernandez-Arquero, Miguel; Khalili, Houman; de la Concha, Emilio G; Urcelay, Elena; Gregersen, Peter K

    2009-10-01

    Previous studies have suggested that the ancestral haplotype 18.2 (AH18.2) carries additional susceptibility gene to Type 1 Diabetes (T1D) on the Major Histocompatibility Complex (MHC). We analyzed 10 DR3/TNFa1b5 homozygous subjects in order to establish the conservation of the AH18.2 and then compared this conserved region with other DR3 haplotype, the AH8.1. The Illumina's HumanHap550 Bead chip was used to perform an extensive genotyping of the MHC region. The AH18.2 was highly conserved between DDR1 and HLA-DQA1 genes; therefore most probably the second susceptibility gene is located within this region. We can exclude the region centromeric to HLA-DRA gene and telomeric to DDR1 gene. A comparison between the AH18.2 and AH8.1 haplotypes showed that 233 SNPs were different in the aforementioned conserved region. These data suggest that the 1.65 Mb MHC region between DDR1 and HLA-DRA genes is likely to carry additional susceptibility alleles for T1D on the AH18.2 haplotype. PMID:19591919

  11. Reducing animal sequencing redundancy by preferentially selecting animals with low-frequency haplotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many studies leverage targeted whole genome sequencing (WGS) experiments in order to identify rare and causal variants within populations. As a natural consequence of experimental design, many of these surveys tend to sequence redundant haplotype segments due to high frequency in the base population...

  12. Beta-globin gene cluster haplotype frequencies in Khalkhs and Buryats of Mongolia.

    PubMed

    Shimizu, Koji; Tokimasa, Kozue; Takeuchi, Yukiko; Gereksaikhan, Tudevdagva; Tanabe, Yuichi; Omoto, Keiichi; Imanishi, Tadashi; Harihara, Shinji; Hao, Luping; Jing, Feng

    2006-12-01

    Beta-globin gene cluster haplotype frequencies of 169 Khalkhs and 145 Buryats were estimated, and their characteristics were compared with those of Evenkis, Oroqens, Koreans, Japanese, and three Colombian Amerindian groups. The present study suggests that Colombian Amerindians diverged first from Asian populations and then Buryats diverged from other Asian populations. PMID:17564253

  13. Reducing animal sequencing redundancy by preferentially selecting animals with low-frequency haplotypes.

    PubMed

    Bickhart, D M; Hutchison, J L; Null, D J; VanRaden, P M; Cole, J B

    2016-07-01

    Many studies leverage targeted whole-genome sequencing (WGS) experiments to identify rare and causal variants within populations. As a natural consequence of their experimental design, many of these surveys tend to sequence redundant haplotype segments due to their high frequency in the base population, and the variants discovered within sequencing data are difficult to phase. We propose a new algorithm, called inverse weight selection (IWS), that preferentially selects individuals based on the cumulative presence of rare frequency haplotypes to maximize the efficiency of WGS surveys. To test the efficacy of this method, we used genotype data from 112,113 registered Holstein bulls derived from the US national dairy database. We demonstrate that IWS is at least 6.8% more efficient than previously published methods in selecting the least number of individuals required to sequence all haplotype segments ≥4% frequency in the US Holstein population. We also suggest that future surveys focus on sequencing homozygous haplotype segments as a first pass to achieve a 50% reduction in cost with an added benefit of phasing variant calls efficiently. Together, this new selection algorithm and experimental design suggestion significantly reduce the overall cost of variant discovery through WGS experiments, making surveys for causal variants influencing disease and production even more efficient. PMID:27085415

  14. Haplotype frequencies at the DRD2 locus in populations of the East European Plain

    PubMed Central

    Flegontova, Olga V; Khrunin, Andrey V; Lylova, Olga I; Tarskaia, Larisa A; Spitsyn, Victor A; Mikulich, Alexey I; Limborska, Svetlana A

    2009-01-01

    Background It was demonstrated previously that the three-locus RFLP haplotype, TaqI B-TaqI D-TaqI A (B-D-A), at the DRD2 locus constitutes a powerful genetic marker and probably reflects the most ancient dispersal of anatomically modern humans. Results We investigated TaqI B, BclI, MboI, TaqI D, and TaqI A RFLPs in 17 contemporary populations of the East European Plain and Siberia. Most of these populations belong to the Indo-European or Uralic language families. We identified three common haplotypes, which occurred in more than 90% of chromosomes investigated. The frequencies of the haplotypes differed according to linguistic and geographical affiliation. Conclusion Populations in the northwestern (Byelorussians from Mjadel'), northern (Russians from Mezen' and Oshevensk), and eastern (Russians from Puchezh) parts of the East European Plain had relatively high frequencies of haplotype B2-D2-A2, which may reflect admixture with Uralic-speaking populations that inhabited all of these regions in the Early Middle Ages. PMID:19793394

  15. Fish scales and SNP chips: SNP genotyping and allele frequency estimation in individual and pooled DNA from historical samples of Atlantic salmon (Salmo salar)

    PubMed Central

    2013-01-01

    Background DNA extracted from historical samples is an important resource for understanding genetic consequences of anthropogenic influences and long-term environmental change. However, such samples generally yield DNA of a lower amount and quality, and the extent to which DNA degradation affects SNP genotyping success and allele frequency estimation is not well understood. We conducted high density SNP genotyping and allele frequency estimation in both individual DNA samples and pooled DNA samples extracted from dried Atlantic salmon (Salmo salar) scales stored at room temperature for up to 35 years, and assessed genotyping success, repeatability and accuracy of allele frequency estimation using a high density SNP genotyping array. Results In individual DNA samples, genotyping success and repeatability was very high (> 0.973 and > 0.998, respectively) in samples stored for up to 35 years; both increased with the proportion of DNA of fragment size > 1000 bp. In pooled DNA samples, allele frequency estimation was highly repeatable (Repeatability = 0.986) and highly correlated with empirical allele frequency measures (Mean Adjusted R2 = 0.991); allele frequency could be accurately estimated in > 95% of pooled DNA samples with a reference group of at least 30 individuals. SNPs located in polyploid regions of the genome were more sensitive to DNA degradation: older samples had lower genotyping success at these loci, and a larger reference panel of individuals was required to accurately estimate allele frequencies. Conclusions SNP genotyping was highly successful in degraded DNA samples, paving the way for the use of degraded samples in SNP genotyping projects. DNA pooling provides the potential for large scale population genetic studies with fewer assays, provided enough reference individuals are also genotyped and DNA quality is properly assessed beforehand. We provide recommendations for future studies intending to conduct high-throughput SNP

  16. TERT rs2736100 A>C SNP and JAK2 46/1 haplotype significantly contribute to the occurrence of JAK2 V617F and CALR mutated myeloproliferative neoplasms - a multicentric study on 529 patients.

    PubMed

    Trifa, Adrian P; Bănescu, Claudia; Tevet, Mihaela; Bojan, Anca; Dima, Delia; Urian, Laura; Török-Vistai, Tünde; Popov, Viola M; Zdrenghea, Mihnea; Petrov, Ljubomir; Vasilache, Anca; Murat, Meilin; Georgescu, Daniela; Popescu, Mihaela; Pătrinoiu, Oana; Balea, Marius; Costache, Roxana; Coleș, Elena; Șaguna, Carmen; Berbec, Nicoleta; Vlădăreanu, Ana-Maria; Mihăilă, Romeo G; Bumbea, Horia; Cucuianu, Andrei; Popp, Radu A

    2016-07-01

    Polycythaemia vera (PV), essential thrombocythaemia (ET) and primary myelofibrosis (PMF) represent typical myeloproliferative neoplasms (MPN), usually characterized by specific somatic driver mutations (JAK2 V617F, CALR and MPL). JAK2 46/1 haplotype and telomerase reverse transcriptase gene (TERT) rs2736100 A>C single nucleotide polymorphism (SNP) could represent a large fraction of the genetic predisposition seen in MPN. The rs10974944 C>G SNP, tagging the JAK2 46/1 haplotype, and the TERT rs2736100 A>C SNP were genotyped in 529 MPN patients with known JAK2 V617F, CALR and MPL status, and 433 controls. JAK2 46/1 haplotype strongly correlated to JAK2 V617F-positive MPN and, to a lesser extent, CALR-positive MPN. The TERT rs2736100 A>C SNP strongly correlated to all MPN, regardless of the phenotype (PV, ET or PMF) and major molecular subtype (JAK2 V617F- or CALR-positive). While both variants have a significant contribution, they have nuanced consequences, with JAK2 46/1 predisposing essentially to JAK2 V617F-positive MPN, and TERT rs2736100 A>C having a more general, non-specific effect on all MPN, regardless of phenotype or major molecular subtype. PMID:27061303

  17. SNP-VISTA

    Energy Science and Technology Software Center (ESTSC)

    2005-11-07

    SNP-VISTA aids in analyses of the following types of data: A. Large-scale re-sequence data of disease-related genes for discovery of associated and/or causative alleles (GeneSNP-VISTA). B. Massive amounts of ecogenomics data for studying homologous recombination in microbial populations (EcoSNP-VISTA). The main features and capabilities of SNP-VISTA are: 1) Mapping of SNPs to gene structure; 2) classification of SNPs, based on their location in the gene, frequency of occurrence in samples and allele composition; 3) clustering,more » based on user-defined subsets of SNPs, highlighting haplotypes as well as recombinant sequences; 4) integration of protein conservation visualization; and 5) display of automatically calculated recombination points that are user-editable. The main strength of SNP-VISTA is its graphical interface and use of visual representations, which support interactive exploration and hence better understanding of large-scale SNPs data.« less

  18. New data for AG haplotype frequencies in Caucasoid populations and selective neutrality of the AG polymorphism.

    PubMed

    Sanchez-Mazas, A; Bütler-Brunner, E; Excoffier, L; Ghanem, N; Ben Salem, M; Breguet, G; Dard, P; Pellegrini, B; Tikkanen, M J; Langaney, A

    1994-02-01

    We present the results of AG antigen typings of three Caucasoid population samples: Lebanese, Tunisians, and Finns. AG haplotype frequencies estimated by maximum-likelihood methods are compared with the frequencies observed in 13 world populations previously tested for AG specificities by computing a genetic distance matrix used in a multivariate analysis. A high degree of polymorphism characterizes the three samples, with 10 haplotypes detected in the Lebanese and 11 haplotypes detected in the Tunisians and Finns; high heterozygosity levels are also present in the three populations. The genetic distance analysis shows that the three populations possess a genetic structure intermediate between those observed in sub-Saharan Africans and in Caucasoids from the Near East and India. This tight correspondence between AG differentiation and geography is confirmed by a highly significant correlation coefficient found between genetic and geographic distances computed worldwide, suggesting that an isolation by distance model of evolution applies to the AG system. The Ewens-Watterson test for selective neutrality on all world populations tested for AG specificities also supports the hypothesis that the AG system behaves like a neutral polymorphism. Overall, the AG differentiation pattern appears to be close to the patterns observed for other serological polymorphisms, such as RH, GM, and HLA, whose evolutionary mechanisms are also discussed. PMID:8157263

  19. Transcriptional defect of an inherited NKX2-5 haplotype comprising a SNP, a nonsynonymous and a synonymous mutation, associated with human congenital heart disease.

    PubMed

    Reamon-Buettner, Stella Marie; Sattlegger, Evelyn; Ciribilli, Yari; Inga, Alberto; Wessel, Armin; Borlak, Jürgen

    2013-01-01

    Germline mutations in cardiac-specific transcription factor genes have been associated with congenital heart disease (CHD) and the homeodomain transcription factor NKX2-5 is an important member of this group. Indeed, more than 40 heterozygous NKX2-5 germline mutations have been observed in individuals with CHD, and these are spread along the coding region, with many shown to impact protein function. In pursuit of understanding causes of CHD, we analyzed n = 49 cardiac biopsies from 28 patients and identified by direct sequencing two nonsynonymous NKX2-5 alterations affecting alanine 119, namely c.356C>A (p.A119E) and c.355G>T, (p.A119S), in patients with AVSD and HLHS, respectively. In functional assays, a significant reduction in transcriptional activities could be determined for the NKX2-5 variants. Importantly, in one family the mother, besides p.A119E, carried a synonymous mutant allele in the homeodomain (c.543G>A, p.Q181), and a synonymous dbSNP (c.63A>G, p.E21) in the transactivation domain of the protein, that were transmitted to the CHD daughter. The presence of these variants in-cis with the p.A119E mutation led to a further reduction in transcriptional activities. Such difference in activity may be in part related to reduced protein expression for the double variant c.356C>A and c.543G>A. We propose changes in mRNA stability and folding, due to a silent mutation and a dbSNP in the NKX2-5 coding region to contribute to the functional defect. Although the clinical significance of the NKX2-5 haplotype identified in the CHD patients remains to be ascertained, we provide evidence of an interaction of a dbSNP, with synonymous and nonsynonymous mutations to negatively impact NKX2-5 transcriptional activity. PMID:24376681

  20. Transcriptional Defect of an Inherited NKX2-5 Haplotype Comprising a SNP, a Nonsynonymous and a Synonymous Mutation, Associated with Human Congenital Heart Disease

    PubMed Central

    Reamon-Buettner, Stella Marie; Sattlegger, Evelyn; Ciribilli, Yari; Inga, Alberto; Wessel, Armin; Borlak, Jürgen

    2013-01-01

    Germline mutations in cardiac-specific transcription factor genes have been associated with congenital heart disease (CHD) and the homeodomain transcription factor NKX2-5 is an important member of this group. Indeed, more than 40 heterozygous NKX2-5 germline mutations have been observed in individuals with CHD, and these are spread along the coding region, with many shown to impact protein function. In pursuit of understanding causes of CHD, we analyzed n = 49 cardiac biopsies from 28 patients and identified by direct sequencing two nonsynonymous NKX2-5 alterations affecting alanine 119, namely c.356C>A (p.A119E) and c.355G>T, (p.A119S), in patients with AVSD and HLHS, respectively. In functional assays, a significant reduction in transcriptional activities could be determined for the NKX2-5 variants. Importantly, in one family the mother, besides p.A119E, carried a synonymous mutant allele in the homeodomain (c.543G>A, p.Q181), and a synonymous dbSNP (c.63A>G, p.E21) in the transactivation domain of the protein, that were transmitted to the CHD daughter. The presence of these variants in-cis with the p.A119E mutation led to a further reduction in transcriptional activities. Such difference in activity may be in part related to reduced protein expression for the double variant c.356C>A and c.543G>A. We propose changes in mRNA stability and folding, due to a silent mutation and a dbSNP in the NKX2-5 coding region to contribute to the functional defect. Although the clinical significance of the NKX2-5 haplotype identified in the CHD patients remains to be ascertained, we provide evidence of an interaction of a dbSNP, with synonymous and nonsynonymous mutations to negatively impact NKX2-5 transcriptional activity. PMID:24376681

  1. Integrating sequence and array data to create an improved 1000 Genomes Project haplotype reference panel.

    PubMed

    Delaneau, Olivier; Marchini, Jonathan

    2014-01-01

    A major use of the 1000 Genomes Project (1000 GP) data is genotype imputation in genome-wide association studies (GWAS). Here we develop a method to estimate haplotypes from low-coverage sequencing data that can take advantage of single-nucleotide polymorphism (SNP) microarray genotypes on the same samples. First the SNP array data are phased to build a backbone (or 'scaffold') of haplotypes across each chromosome. We then phase the sequence data 'onto' this haplotype scaffold. This approach can take advantage of relatedness between sequenced and non-sequenced samples to improve accuracy. We use this method to create a new 1000 GP haplotype reference set for use by the human genetic community. Using a set of validation genotypes at SNP and bi-allelic indels we show that these haplotypes have lower genotype discordance and improved imputation performance into downstream GWAS samples, especially at low-frequency variants. PMID:25653097

  2. Molecular analysis of human leukocyte antigen class I and class II allele frequencies and haplotype distribution in Pakistani population

    PubMed Central

    Moatter, T.; Aban, M.; Tabassum, S.; Shaikh, U.; Pervez, S.

    2010-01-01

    AIM: Distribution of HLA class I and II alleles and haplotype was studied in Pakistani population and compared with the data reported for Caucasoid, Africans, Orientals and Arab populations. MATERIALS AND METHODS: HLA class I and II polymorphisms in 1000 unrelated Pakistani individuals was studied using sequence-specific primers and polymerase chain reaction and assay. RESULTS: The most frequent class I alleles observed were A*02, B*35 and CW*07, with frequencies of 19.2, 13.7 and 20%, respectively. Fifteen distinct HLA-DRB1 alleles and eight HLA-DQB1 alleles were recognized. The most frequently observed DRB1 alleles which represented more than 60% of the subjects were DRB1 *03, *07, *11 and *15. The rare DRB1 alleles detected in this study were HLADRB1 *08 and *09, having frequencies of 0.9 and 1.7%, respectively. In addition, at DRB1-DQB1 loci there were 179 different haplotypes and 285 unique genotypes and the most common haplotype was DRB1*15-DQB1*06 which represented 17% of the total DRB1-DQB1 haplotypes. In our population, haplotype A*33-B*58-Cw*03 comprised 2.8% of the total class I haplotypes observed. This haplotype was seen only in the oriental populations and has not been reported in the African or European Caucasoid. CONCLUSION: Our study showed a close similarity of HLA class I and II alleles with that of European Caucasoid and Orientals. In Pakistani population, two rare loci and three haplotypes were identified, whereas haplotypes characteristic of Caucasians, Africans and Orientals were also found, suggesting an admixture of different races due to migration to and from this region. PMID:21206703

  3. A substantially lower frequency of uninformative matches between 23 versus 17 Y-STR haplotypes in north Western Europe.

    PubMed

    Larmuseau, Maarten H D; Vanderheyden, Nancy; Van Geystelen, Anneleen; Decorte, Ronny

    2014-07-01

    The analysis of human short tandem repeats of the Y-chromosome (Y-STRs) provides a powerful tool in forensic cases for male sex identification, male lineage identification and identification of the geographical origin of male lineages. As the commonly used 12 and 17 Y-STR multiplexes do not discriminate between some unrelated males, additional Y-STRs were implemented in the PowerPlex(®) Y23 System to supplement the existing commercial Y-STR kits. Until today, the forensic value of a (near) 23 versus 17 Y-STR haplotype match between an unknown DNA donor and a certain biological sample in a database is not yet well studied. This will be of huge interest for cases where an autosomal DNA profile yields no match to a DNA database and the database is used for familial searching (male relative(s) of the offender) or for the estimation of the geographical origin of the offender. In order to value (near) 23 Y-STR haplotype matches in a local sample from Western Europe, we selected the region of Flanders (Belgium) due to the already present knowledge on its Y-chromosomal variants. Many Y-chromosomes of this region were previously genotyped with Y-SNPs at a high resolution of the most recently updated Y-chromosomal tree and the deep-rooted genealogy of each DNA donor was already established. By comparing (near) matches of 23 versus 17 Y-STR haplotypes between patrilineal-unrelated males, a substantial lower number of uninformative (near) 23 Y-STR haplotype matches has been observed compared to 17 Y-STR haplotypes. Furthermore, the use of SNP data was informative to discriminate >60% of unrelated males with an (near) identical 17 Y-STR match while SNP data was only necessary to discriminate about 10% of unrelated males with a 23 Y-STR haplotype that differed at only two Y-STRs. This shows the higher value of the Y23 haplotype within familial DNA searching and the estimation of the geographical origin of a DNA donor. Therefore, the use of the PowerPlex(®) Y23 System instead

  4. Haplotype Association between Haptoglobin (Hp2) and Hp Promoter SNP (A-61C) May Explain Previous Controversy of Haptoglobin and Malaria Protection

    PubMed Central

    Cox, Sharon E.; Doherty, Conor; Atkinson, Sarah H.; Nweneka, Chidi V.; Fulford, Anthony J.C.; Ghattas, Hala; Rockett, Kirk A.; Kwiatkowski, Dominic P.; Prentice, Andrew M.

    2007-01-01

    Background Malaria is one of the strongest recent selective pressures on the human genome, as evidenced by the high levels of varying haemoglobinopathies in human populations–despite the increased risk of mortality in the homozygous states. Previously, functional polymorphisms of Hp, coded by the co-dominant alleles Hp1 and Hp2, have been variously associated with several infectious diseases, including malaria susceptibility. Methodology/Principal Findings Risk of a clinical malarial episode over the course of a malarial transmission season was assessed using active surveillance in a cohort of Gambian children aged 10–72 months. We report for the first time that the major haplotype for the A-61C mutant allele in the promoter of haptoglobin (Hp)–an acute phase protein that clears haemoglobin released from haemolysis of red cells–is associated with protection from malarial infection in older children, (children aged ≥36 months, >500 parasites/ul and temperature >37.5°C; OR = 0.42; [95% CI 0.24–0.73] p = 0.002) (lr test for interaction, <36 vs ≥36 months, p = 0.014). Protection was also observed using two other definitions, including temperature >37.5°C, dipstick positive, plus clinical judgement of malaria blinded to dipstick result (all ages, OR = 0.48, [95% CI 0.30–0.78] p = 0.003; ≥36 months, OR = 0.31, [95% CI 0.15–0.62] p = 0.001). A similar level of protection was observed for the known protective genetic variant, sickle cell trait (HbAS). Conclusions/Significance We propose that previous conflicting results between Hp phenotypes/genotypes and malaria susceptibility may be explained by differing prevalence of the A-61C SNP in the populations studied, which we found to be highly associated with the Hp2 allele. We report the -61C allele to be associated with decreased Hp protein levels (independent of Hp phenotype), confirming in vitro studies. Decreased Hp expression may lead to increased oxidant stress and

  5. Frequency of alleles and haplotypes of the human leukocyte antigen system in Bauru São Paulo, Brazil

    PubMed Central

    Salvadori, Luana de Cassia; Santana, Fabiana Covolo de Souza; Marcos, Elaine Valim Camarinha

    2014-01-01

    Background HLA allele identification is used in bone marrow transplant programs as HLA compatibility between the donor and recipient may prevent graft rejection. Objective This study aimed to estimate the frequency of alleles and haplotypes of the HLA system in the region of Bauru and compare these with the frequencies found in other regions of the country. Methods HLA-A*, HLA-B*, and HLA-DRB1* allele frequencies and haplotypes were analyzed in a sample of 3542 volunteer donors at the National Registry of Voluntary Bone Marrow Donors (REDOME) in Bauru. HLA low resolution typing was performed using reverse line blot with the Dynal Reli™ SSO-HLA Typing Kit and automated Dynal AutoReli™48 device (Invitrogen, USA). Results Twenty, 36, and 13 HLA-A*, HLA-B*, and HLA-DRB1* allele groups, respectively, were identified. The most common alleles for each locus were HLA-A*02, HLA-B*35, and HLA-DRB1*07. The most frequent haplotype was A*01-B*08-DRB1*03. Allele and haplotype frequencies were compared to other regions in Brazil and the similarities and differences among populations are shown. Conclusion The knowledge of the immunogenic profile of a population contributes to the comprehension of the historical and anthropological aspects of different regions. Moreover, this helps to find suitable donors quickly, thereby shortening waiting lists for transplants and thus increasing survival rates among recipients.

  6. Frequencies of two functionally significant SNPs and their haplotypes of organic anion transporting polypeptide 1B1 SLCO1B1 gene in six ethnic groups of Pakistani population

    PubMed Central

    Rajput, Tausif Ahmed; Naveed, Abdul Khaliq; Khan, Shakir; Farooqi, Zia-Ur-Rehman

    2014-01-01

    Objective(s): Organic anion transporter polypeptide 1B1 (OATP1B1) encoded by solute carrier organic transporter 1B1 (SLCO1B1) gene; a transporter involved in the uptake of drugs and endogenous compounds is present in hepatocyte sinusoidal membrane. Aim of this study was to investigate the frequencies of functionally significant SNPs (388A>G and 521T>C) and their haplotypes in 6 ethnic groups of Pakistani population through the development of rapid and efficient Tetra amplification refractory mutation system (T. ARMS) genotyping assay. Materials and Methods: Frequencies of alleles, genotype, and haplotypes of two functionally significant Single nucleotide polymorphism in 180 healthy Pakistani subjects and distributions in six ethnic groups by using a single step T. ARMS genotyping assay. Results: The allelic frequency for 388A>G SNP was 50% in total Pakistani population with Single nucleotide polymorphism distributions of 9.7%, 15.1%, 19.4%, 16.1%, 18.3%, and 21.5% in Punjabi, Sindhi, Balouchi, Pathan, Kashmiri and Hazara/Baltistan groups respectively; and for 521T>C SNP it was 23.9% in total Pakistani population with distributions of 11.1%, 8.9%, 15.6%, 11.1%, 31.1% and 22.2% in Punjabi, Sindhi, Balouchi, Pathan, Kashmiri, and Hazara/Baltistan groups. Both functionally significant SNPs occurred in four major haplotypes with a frequency of 35.5% for 388A/521T (*1A), 40.5% for 388G/521T (*1B), 14.4% for 388A/521C (*5), and 9.4% for 388G/521C (*15) with varying distributions among six ethnic groups. Conclusion: The 388A>G and 521T>C genotypes and corresponding haplotypes are present at varying frequencies in various ethnic groups of Pakistani population. Pharmacokinetic and pharmacodynamic profiling is needed to assess and characterize the effects of these haplotypes in our population. PMID:25140206

  7. Application of site and haplotype-frequency based approaches for detecting selection signatures in cattle

    PubMed Central

    2011-01-01

    Background 'Selection signatures' delimit regions of the genome that are, or have been, functionally important and have therefore been under either natural or artificial selection. In this study, two different and complementary methods--integrated Haplotype Homozygosity Score (|iHS|) and population differentiation index (FST)--were applied to identify traces of decades of intensive artificial selection for traits of economic importance in modern cattle. Results We scanned the genome of a diverse set of dairy and beef breeds from Germany, Canada and Australia genotyped with a 50 K SNP panel. Across breeds, a total of 109 extreme |iHS| values exceeded the empirical threshold level of 5% with 19, 27, 9, 10 and 17 outliers in Holstein, Brown Swiss, Australian Angus, Hereford and Simmental, respectively. Annotating the regions harboring clustered |iHS| signals revealed a panel of interesting candidate genes like SPATA17, MGAT1, PGRMC2 and ACTC1, COL23A1, MATN2, respectively, in the context of reproduction and muscle formation. In a further step, a new Bayesian FST-based approach was applied with a set of geographically separated populations including Holstein, Brown Swiss, Simmental, North American Angus and Piedmontese for detecting differentiated loci. In total, 127 regions exceeding the 2.5 per cent threshold of the empirical posterior distribution were identified as extremely differentiated. In a substantial number (56 out of 127 cases) the extreme FST values were found to be positioned in poor gene content regions which deviated significantly (p < 0.05) from the expectation assuming a random distribution. However, significant FST values were found in regions of some relevant genes such as SMCP and FGF1. Conclusions Overall, 236 regions putatively subject to recent positive selection in the cattle genome were detected. Both |iHS| and FST suggested selection in the vicinity of the Sialic acid binding Ig-like lectin 5 gene on BTA18. This region was recently reported

  8. SNP-VISTA: An interactive SNP visualization tool

    PubMed Central

    Shah, Nameeta; Teplitsky, Michael V; Minovitsky, Simon; Pennacchio, Len A; Hugenholtz, Philip; Hamann, Bernd; Dubchak, Inna L

    2005-01-01

    Background Recent advances in sequencing technologies promise to provide a better understanding of the genetics of human disease as well as the evolution of microbial populations. Single Nucleotide Polymorphisms (SNPs) are established genetic markers that aid in the identification of loci affecting quantitative traits and/or disease in a wide variety of eukaryotic species. With today's technological capabilities, it has become possible to re-sequence a large set of appropriate candidate genes in individuals with a given disease in an attempt to identify causative mutations. In addition, SNPs have been used extensively in efforts to study the evolution of microbial populations, and the recent application of random shotgun sequencing to environmental samples enables more extensive SNP analysis of co-occurring and co-evolving microbial populations. The program is available at [1]. Results We have developed and present two modifications of an interactive visualization tool, SNP-VISTA, to aid in the analyses of the following types of data: A. Large-scale re-sequence data of disease-related genes for discovery of associated and/or causative alleles (GeneSNP-VISTA). B. Massive amounts of ecogenomics data for studying homologous recombination in microbial populations (EcoSNP-VISTA). The main features and capabilities of SNP-VISTA are: 1) mapping of SNPs to gene structure; 2) classification of SNPs, based on their location in the gene, frequency of occurrence in samples and allele composition; 3) clustering, based on user-defined subsets of SNPs, highlighting haplotypes as well as recombinant sequences; 4) integration of protein evolutionary conservation visualization; and 5) display of automatically calculated recombination points that are user-editable. Conclusion The main strength of SNP-VISTA is its graphical interface and use of visual representations, which support interactive exploration and hence better understanding of large-scale SNP data by the user. PMID

  9. Probability distribution of haplotype frequencies under the two-locus Wright-Fisher model by diffusion approximation.

    PubMed

    Boitard, Simon; Loisel, Patrice

    2007-05-01

    The probability distribution of haplotype frequencies in a population, and the way it is influenced by genetical forces such as recombination, selection, random drift ...is a question of fundamental interest in population genetics. For large populations, the distribution of haplotype frequencies for two linked loci under the classical Wright-Fisher model is almost impossible to compute because of numerical reasons. However the Wright-Fisher process can in such cases be approximated by a diffusion process and the transition density can then be deduced from the Kolmogorov equations. As no exact solution has been found for these equations, we developed a numerical method based on finite differences to solve them. It applies to transient states and models including selection or mutations. We show by several tests that this method is accurate for computing the conditional joint density of haplotype frequencies given that no haplotype has been lost. We also prove that it is far less time consuming than other methods such as Monte Carlo simulations. PMID:17316725

  10. Detecting local haplotype sharing and haplotype association.

    PubMed

    Xu, Hanli; Guan, Yongtao

    2014-07-01

    A novel haplotype association method is presented, and its power is demonstrated. Relying on a statistical model for linkage disequilibrium (LD), the method first infers ancestral haplotypes and their loadings at each marker for each individual. The loadings are then used to quantify local haplotype sharing between individuals at each marker. A statistical model was developed to link the local haplotype sharing and phenotypes to test for association. We devised a novel method to fit the LD model, reducing the complexity from putatively quadratic to linear (in the number of ancestral haplotypes). Therefore, the LD model can be fitted to all study samples simultaneously, and, consequently, our method is applicable to big data sets. Compared to existing haplotype association methods, our method integrated out phase uncertainty, avoided arbitrariness in specifying haplotypes, and had the same number of tests as the single-SNP analysis. We applied our method to data from the Wellcome Trust Case Control Consortium and discovered eight novel associations between seven gene regions and five disease phenotypes. Among these, GRIK4, which encodes a protein that belongs to the glutamate-gated ionic channel family, is strongly associated with both coronary artery disease and rheumatoid arthritis. A software package implementing methods described in this article is freely available at http://www.haplotype.org. PMID:24812308

  11. HLA allele and haplotype frequencies in the Albanian population and their relationship with the other European populations.

    PubMed

    Sulcebe, G; Sanchez-Mazas, A; Tiercy, J-M; Shyti, E; Mone, I; Ylli, Z; Kardhashi, V

    2009-12-01

    Human leucocyte antigen (HLA) alleles are very interesting markers in identifying population relationships. Moreover, their frequency distribution data are important in the implementation of donor-recipient registry programs for transplantation purposes and also in determining the genetic predisposition for many diseases. For these reasons, we studied the HLA class I and II allele and haplotype frequencies in 160 healthy, unrelated Albanian individuals originating from all regions of the country. The HLA genotyping was performed through a 2-digit resolution SSOP method. The data were analysed with Arlequin and Phylip programs. No deviation was found from the Hardy-Weinberg equilibrium. A total of 17 A*, 30 B*, 12 Cw*, 13 DRB1* and 5 DQB1* alleles were identified. The six most frequent HLA-A-B-DRB1 haplotypes were A*02-B*18-DRB1*11 (5.60%), A*02-B*51-DRB1*16 (4.74%), A*01-B*08-DRB1*03 (3.48%), A*24-B*35-DRB1*11 (2.77%), A*02-B*51-DRB1*13 (2.21%), A*24-B*35-DRB1*14 (1.89%). Interestingly, 12 HLA-A-B-Cw-DRB1-DQB1 haplotypes occurred at a frequency >1%. When compared with the other populations, a close relationship was found with North Greek, Bulgarian, Macedonian, Romanian, Turkish, Cretan, Serbian, Croatian and Italian populations. A higher differentiation in allele frequency level was found with Western Europe populations. These data are the first report of HLA allele and haplotype distribution in an Albanian population inside this country. When compared with other populations, their distribution frequencies show close similarities with neighbouring populations of the entire Balkan area. PMID:19703234

  12. SNP discovery and allele frequency estimation by deep sequencing of reduced representation libraries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genome projects routinely produce draft sequences for species from diverse evolutionary clades, but generally do not create single nucleotide polymorphism (SNP) resources. We present an approach for de novo SNP discovery based on short-read sequencing of reduced representation libraries (RRL) to ge...

  13. The likelihood ratio and frequency of DQ2/DQ8 haplotypes in Iranian patients with celiac disease

    PubMed Central

    Khosravi, Asghar; Mansouri, Masoume; Rostami-Nejad, Mohammad; Shahbazkhani, Bijan; Ekhlasi, Golnaz; Kalantari, Ebrahim

    2016-01-01

    Aim: The aim of this study was to evaluate the likelihood ratio and frequency of DQ2 and DQ8 in Iranian patients with celiac disease (CD). Background: The HLA DQ2 and HLA DQ8 are the important mediators in the development of celiac disease. A few studies evaluated the frequency of HLA DQ2 and HLA DQ8 haplotypes among the Iranian population with low sample size. Patients and methods: In this cross-sectional study, to predict HLA–DQ2 and DQ8 haplotypes, 141(73 male, 78 female) confirmed CD patients compared to 151 healthy controls were enrolled into this study during 2013-2014. HLA DQ2/ DQ8 haplotypes was determined in cases and controls using PCR-SSP technique. Results: DQ2 and DQ8 were positive in 80% (n=111) and 49% (n= 69) of CD patients and 36% (n=61) and 13% (n=21) of control group respectively. Moreover, 32% (n=45) of CD patients and 5.3% (n=8) of the control group were carrier of both haplotypes. In the case group about one-third of patients (32.2%) were positive for carrying both DQ2 and DQ8 heterodimers while only 5.3% (n=8) of the control group were carrier. In addition, the positive likelihood ratio of DQ2 and DQ8 were 1.74 (CI: 1.4- 2.1), and 2.6 (CI: 1.8– 2.7), respectively. Conclusion: The result of this study showed that the frequency of DQ8 among our population is higher than those reported by European countries, but it is close to those founded in South America and Middle East. This result suggests that the higher prevalence of HLA DQ8 pattern in Iranian CD patients is similar to non-European patients. PMID:26744610

  14. μ-Calpain, calpastatin, and growth hormone receptor genetic effects on preweaning performance, carcass quality traits, and residual variance of tenderness in Angus cattle selected to increase minor haplotype and allele frequencies.

    PubMed

    Tait, R G; Shackelford, S D; Wheeler, T L; King, D A; Casas, E; Thallman, R M; Smith, T P L; Bennett, G L

    2014-02-01

    Genetic marker effects and interactions are estimated with poor precision when minor marker allele frequencies are low. An Angus population was subjected to marker assisted selection for multiple years to increase divergent haplotype and minor marker allele frequencies to 1) estimate effect size and mode of inheritance for previously reported SNP on targeted beef carcass quality traits; 2) estimate effects of previously reported SNP on nontarget performance traits; and 3) evaluate tenderness SNP specific residual variance models compared to a single residual variance model for tenderness. Divergent haplotypes within µ-calpain (CAPN1), and SNP within calpastatin (CAST) and growth hormone receptor (GHR) were successfully selected to increase their frequencies. Traits evaluated were birth BW, weaning BW, final BW, fat thickness, LM area, USDA marbling score, yield grade, slice shear force (SSF), and visible and near infrared predicted slice shear force. Both CAPN1 and CAST exhibited additive (P < 0.001) modes of inheritance for SSF and neither exhibited dominance (P ≥ 0.19). Furthermore, the interaction between CAPN1 and CAST for SSF was not significant (P = 0.55). Estimated additive effects of CAPN1 (1.049 kg) and CAST (1.257 kg) on SSF were large in this study. Animals homozygous for tender alleles at both CAPN1 and CAST would have 4.61 kg lower SSF (38.6% of the mean) than animals homozygous tough for both markers. There was also an effect of CAST on yield grade (P < 0.02). The tender CAST allele was associated with more red meat yield and less trimmable fat. There were no significant effects (P ≥ 0.23) for GHR on any of the traits evaluated in this study. Furthermore, CAST specific residual variance models were found to fit significantly better (P < 0.001) than single residual variance models for SSF, with the tougher genotypes having larger residual variance. Thus, the risk of a tough steak from the undesired CAST genotype is increased through both an

  15. HLA-A, -B, -C, -DRB1 Allele and Haplotype Frequencies Distinguish Eastern European Americans from the General European American Population

    PubMed Central

    Mack, Steven J.; Tu, Bin; Lazaro, Ana; Yang, Ruyan; Lancaster, Alex K.; Cao, Kai; Ng, Jennifer; Hurley, Carolyn Katovich

    2012-01-01

    Sequence based typing was used to identify HLA-A,B,C,DRB1 alleles from 558 consecutively recruited U.S. volunteers with Eastern European ancestry for an unrelated hematopoietic stem cell registry. Four of the 31 HLA-A alleles, 29 -C alleles, 59 -B alleles, and 42 -DRB1 alleles identified (A*0325, B*440204, Cw*0332, and *0732N) are novel. The HLA-A*02010101g allele was observed at a frequency of 0.28. Two-, three- and four-locus haplotypes were estimated using the expectation maximization algorithm. The highest-frequency extended haplotypes (A*010101g-Cw*070101g-B*0801g-DRB1*0301 and A*03010101g-Cw*0702-B*0702-DRB1*1501) were observed at frequencies of 0.04 and 0.03, respectively. Linkage disequilibrium values (D’ij) of the constituent 2-locus haplotypes were highly significant for both extended haplotypes (p-values were less than 8 × 10−10), but were consistently higher for the more frequent haplotype. Balancing selection was inferred to be acting on all four loci, with the strongest evidence of balancing selection observed for the HLA-C locus. Comparisons of the A-C-B haplotype and DRB1 frequencies in this population to those for African, European and western Asian populations revealed high degrees of identity with Czech, Polish, and Slovenian populations and significant differences from the general European American population. PMID:19000140

  16. Infection Frequency of Hepatitis C Virus and IL28B Haplotypes in Papua New Guinea, Fiji, and Kiribati

    PubMed Central

    Harrison, G. L. Abby; Pryor, Jan; Malani, Joji; Supuri, Mathias; Masta, Andrew; Teriboriki, Burentau; Toatu, Tebuka; Penny, David; Allain, Jean-Pierre; Barnes, Eleanor; Pybus, Oliver G.; Klenerman, Paul

    2013-01-01

    It has been estimated that there are more than 60 million Hepatitis C virus (HCV) carriers in the World Health Organisation's Western Pacific region (WHO-WPR), where liver cancer is among the top three causes of cancer death. WHO and the US Centres for Disease Control and Prevention report the prevalence of HCV in the South Pacific islands (countries within the WHO-WPR) to be high (5–10% and >2% respectively). However, since HCV is not tested for in many of these countries, there is sparse data available to support this assertion. We screened ∼2000 apparently healthy individuals from Papua New Guinea, Fiji and Kiribati and found a sero-prevalence of 2.0%, 0.1% and 0%, respectively. All sero-positive samples tested negative for HCV RNA. Curious as to why all the sero-positive individuals were negative for HCV-RNA, we also screened them for the HCV protective IL28B SNP markers rs12979860 and rs8099917. All antibody-positive participants bar one had HCV protective haplotypes. Our results suggest that HCV is present in these Pacific island countries, albeit at a prevalence lower than previous estimates. As none of our participants had undergone antiviral treatment, and therefore must have cleared infection naturally, we hypothesise that genotypes 1 and/or 4 are circulating in South Pacific Island people and that these peoples are genetically predisposed to be more likely to spontaneous resolve HCV infection than to become chronic carriers. PMID:23976941

  17. HLA gene and haplotype frequencies in Russians, Bashkirs and Tatars, living in the Chelyabinsk Region (Russian South Urals).

    PubMed

    Suslova, T A; Burmistrova, A L; Chernova, M S; Khromova, E B; Lupar, E I; Timofeeva, S V; Devald, I V; Vavilov, M N; Darke, C

    2012-10-01

    We have characterized the HLA-A, -B, -DRB1, -DQA1 and -DQB1 profiles of three major ethnic groups living in Chelyabinsk Region of Russian South Urals, viz., Russians (n = 207), Bashkirs (n = 146) and Tatars (n = 135). First field level typing was performed by PCR using sequence-specific primers. Estimates included carriage and gene frequencies, linkage disequilibrium and its significance and related values. Population comparisons were made between the allele family frequencies of the three populations and between these populations and 20 others using a dendrogram. Chelyabinsk Region Russians demonstrate all the features typical of a Caucasoid population, but also have some peculiarities. Together with Tatars, Russians have high frequencies of allele families and haplotypes characteristic of Finno-Ugric populations. This presupposes a Finno-Ugric impact on Russian and Tatar ethnogenesis. However, this was not apparent in Bashkirs, the first of the three populations to live in this territory, and implies admixture with populations of a Finno-Ugric origin with precursors of Russians and Tatars before they came to the South Urals. The Bashkirs appear close to Mongoloids in allele and haplotype distribution. However, Bashkirs cannot be labelled either as typical Mongoloids or as Caucasoids. Thus, Bashkirs possess some alleles and haplotypes frequent in Mongoloids, which supports the Turkic impact on Bashkir ethnogenesis, but also possess the AH 8.1 haplotype, which could evidence an ancient Caucasoid population that took part in their ethnic formation or of recent admixture with adjacent populations (Russians and Tatars). Bashkirs showed no features of populations with a substantial Finno-Ugric component, for example Chuvashes or Russian Saami. This disputes the commonly held belief of a Finno-Ugric origin for Bashkirs. Tatars appeared close to many European populations. However, they possessed some characteristics of Asiatic populations possibly reflecting a Mongoloid

  18. Haplotyping algorithms

    SciTech Connect

    Sobel, E.; Lange, K.; O`Connell, J.R.

    1996-12-31

    Haplotyping is the logical process of inferring gene flow in a pedigree based on phenotyping results at a small number of genetic loci. This paper formalizes the haplotyping problem and suggests four algorithms for haplotype reconstruction. These algorithms range from exhaustive enumeration of all haplotype vectors to combinatorial optimization by simulated annealing. Application of the algorithms to published genetic analyses shows that manual haplotyping is often erroneous. Haplotyping is employed in screening pedigrees for phenotyping errors and in positional cloning of disease genes from conserved haplotypes in population isolates. 26 refs., 6 figs., 3 tabs.

  19. An Analysis of HLA-A, -B, and -DRB1 Allele and Haplotype Frequencies of 21,918 Residents Living in Liaoning, China

    PubMed Central

    Li, Xiao-Feng; Zhang, Xu; Chen, Yang; Zhang, Kun-Lian; Liu, Xiang-Jun; Li, Jian-Ping

    2014-01-01

    HLA-A, -B and -DRB1 allele frequencies and their haplotype frequencies in 21,918 Chinese residents living in Liaoning Province, who were registered as volunteer donors of China Marrow Donor Registry, were investigated. They are composed of 93.37% Han Chinese, 5.1% Manchus, 0.57% Mongols, 0.46% Hui persons, 0.29% Koreans and 0.14% Xibe ethnic group. In total eighteen different HLA-A alleles, forty-eight different HLA-B alleles and fourteen different HLA-DRB1 alleles have been identified. Their frequencies are in agreement with the Hardy-Weinberg equilibrium. For Han Chinese in Liaoning, 1,534 different HLA-A-B-DRB1 haplotypes were identified, with a frequency of higher than 0.01%. A*30-B*13-DRB1*07, A*02-B*46-DRB1*09 and A*02-B*13-DRB1*12 are the most frequent haplotypes among Liaoning Han. While Liaoning Han, Liaoning Manchu, Liaoning Mongol, Liaoning Hui and Liaoning Korean share the northern Han characteristic haplotypes, all minority ethnic groups with the exception of Liaoning Manchu have developed their own unique HLA profiles. This dataset characterizes the HLA allele and haplotype frequencies in the Liaoning area and suggests that it is different from those in other parts of China and ethnic groups, which implicates transplant donor searching strategies and studies on population genetics. PMID:24691290

  20. A recursive method for solving haplotype frequencies with application to genetics.

    PubMed

    Ng, Michael K; Fung, Eric S; Lee, Yiu-Fai; Ching, Wai-Ki

    2006-12-01

    Multiple loci analysis has become popular with the advanced developments in biological experiments. A lot of studies have been focused on the biological and the statistical properties of such multiple loci analysis. In this paper, we study one of the important computational problems: solving the probabilities of haplotype classes from a large linear system Ax = b derived from the recombination events in multiple loci analysis. Since the size of the recombination matrix A increases exponentially with respect to the number of loci, fast solvers are required to deal with a large number of loci in the analysis. By exploiting the nice structure of the matrix A, we develop an efficient recursive algorithm for solving such structured linear systems. In particular, the complexity of the proposed algorithm for the n loci problem is of O(n2(n)) operations and the memory requirement is of O(2(n)) locations for the 2(n)-by-2(n) matrix A. Numerical examples are given to demonstrate the effectiveness of our efficient solver. Finally, we apply our proposed method to analyze the haplotype classes for a set of single nucleotides polymorphisms (SNPs) from Hapmap data. PMID:17245814

  1. Unique AGG Interruption in the CGG Repeats of the FMR1 Gene Exclusively Found in Asians Linked to a Specific SNP Haplotype

    PubMed Central

    Limprasert, Pornprot; Thanakitgosate, Janpen; Jaruthamsophon, Kanoot; Sripo, Thanya

    2016-01-01

    Fragile X syndrome (FXS) is the most common inherited intellectual disability. It is caused by the occurrence of more than 200 pure CGG repeats in the FMR1 gene. Normal individuals have 6–54 CGG repeats with two or more stabilizing AGG interruptions occurring once every 9- or 10-CGG-repeat blocks in various populations. However, the unique (CGG)6AGG pattern, designated as 6A, has been exclusively reported in Asians. To examine the genetic background of AGG interruptions in the CGG repeats of the FMR1 gene, we studied 8 SNPs near the CGG repeats in 176 unrelated Thai males with 19–56 CGG repeats. Of these 176 samples, we identified AGG interruption patterns from 95 samples using direct DNA sequencing. We found that the common CGG repeat groups (29, 30, and 36) were associated with 3 common haplotypes, GCGGATAA (Hap A), TTCATCGC (Hap C), and GCCGTTAA (Hap B), respectively. The configurations of 9A9A9, 10A9A9, and 9A9A6A9 were commonly found in chromosomes with 29, 30, and 36 CGG repeats, respectively. Almost all chromosomes with Hap B (22/23) carried at least one 6A pattern, suggesting that the 6A pattern is linked to Hap B and may have originally occurred in the ancestors of Asian populations. PMID:27042357

  2. Allele frequencies and haplotypes for 28 Y-STRs in Ovambo population.

    PubMed

    Fujihara, Junko; Yuasa, Isao; Muro, Tomonori; Iida, Reiko; Tsubota, Etsuko; Nakamura, Hiroaki; Imamura, Shinji; Yasuda, Toshihiro; Takeshita, Haruo

    2009-07-01

    Y-chromosomal 28 short tandem repeat (STR) loci were investigated in unrelated healthy individuals of the Ovambo population from Namibia (n=54). Sixteen Y-chromosome short tandem repeat (Y-STR) polymorphic loci (DYS456, DYS389I, DYS390, DYS389II, DYS458, DYS19, DYS385, DYS393, DYS391, DYS439, DYS635, DYS392, GATAH4, DYS437, DYS438, and DYS448) were analyzed using AmpFISTR Yfiler Polymerase Chain Reaction (PCR) Amplification Kit. DYS441-445 and DYS446, DYS447, DYS449, DYS450, DYS459a/b, DYS463 and DYS464a/b/c/d were investigated using a multiplex PCR system. Fifty-one haplotypes were identified in 54 Ovambos. The STR diversity values for Y-STRs loci ranged from 0.036 (DYS392) to 0.900 (DYS 385). PMID:19442559

  3. [Gene and haplotype frequencies for the loci HLA-A, B and DRB1 in 11755 north Chinese Han bone marrow registry donors].

    PubMed

    Wu, Qiang-Ju; Liu, Meng-Li; Qi, Jun; Liu, Sheng; Zhang, Yan; Wei, Xiao-Qian

    2007-04-01

    The study was aimed to investigate the human leukocyte antigen (HLA)-A, B, DRB1 alleles and haplotype frequencies and the characteristics of linkage disequilibrium in north Chinese Han bone marrow donors. HLA phenotype data of 11 755 north Chinese Han bone marrow donors were identified by PCR-SSP and PCR-SSO. HLA-A, B, DRB1 allele and haplotype frequencies were calculated by computer software named Arleguin which was based on Expectation-Maximization (EM) algorithms. The results showed that the population of 11755 unrelated-donors was tested by Hardy-Weinberg equilibrium, and 18,42 and 15 specificities of HLA alleles were identified on the HLA-A, B, DRB1 locus respectively, including HLA-A25, B42, B53, B73 and DR3 which were rarely reported in Han population. HLA-A36, A43, A80, B78, B82 and DR18 were not detected in this study. The most frequent alleles with a frequency of over 0.05 were HLA-A*02, A*11, A*24, A*33, A*30, A*01, A*03, A*13, B62, B*51, B*46, B60, B61, B*35, B*44, DRB1*15, DRB1*09, DRB1*04, DRB1*07, DRB1*12, DRB1*11, DRB1*14, DRB1*08, DRB1*13. There were a total of 2 026 kinds of HLA-A-B-DR haplotypes (with a frequency of over 10(-6)) to be obtained. The each frequency of 26 kinds of three-locus haplotypes including HLA-A30-B13-DR7, A2-B46-DR9, A33-B58-DR17 etc was higher than 0.005. A30-B13-DR7 was the most frequent haplotype in north Chinese Han population. There were a total of 538 kinds of haplotypes for HLA-A-B, 227 kinds for A-DR and 522 kinds for B-DR to be obtained, and there were 409, 195, 423 kinds of haplotypes respectively with a frequency higher than 10 - 6. There were 28 kinds of HLA-A-B haplotypes including A30-B13, A2-B46, A33-B58 etc, 26 kinds of HLA-A-DR haplotypes including A2-DR9, A2-DR15, A30-DR7 etc, and 24 kinds of HLA-B-DR haplotypes including B13-DR7, B46-DR9, B13-DR12 etc with a frequency higher than 0.01. 296 (72%) kinds of HLA-A-B, 130 (67%) kinds of A-DR and 308 (73%) kinds of B-DR haplotypes were statistical linkage

  4. Haplotyping Problem, A Clustering Approach

    SciTech Connect

    Eslahchi, Changiz; Sadeghi, Mehdi; Pezeshk, Hamid; Kargar, Mehdi; Poormohammadi, Hadi

    2007-09-06

    Construction of two haplotypes from a set of Single Nucleotide Polymorphism (SNP) fragments is called haplotype reconstruction problem. One of the most popular computational model for this problem is Minimum Error Correction (MEC). Since MEC is an NP-hard problem, here we propose a novel heuristic algorithm based on clustering analysis in data mining for haplotype reconstruction problem. Based on hamming distance and similarity between two fragments, our iterative algorithm produces two clusters of fragments; then, in each iteration, the algorithm assigns a fragment to one of the clusters. Our results suggest that the algorithm has less reconstruction error rate in comparison with other algorithms.

  5. Microarray-based estimation of SNP allele-frequency in pooled DNA using the Langmuir kinetic model

    PubMed Central

    Yin, Bin-Cheng; Li, Honghua; Ye, Bang-Ce

    2008-01-01

    Background High throughput genotyping of single nucleotide polymorphisms (SNPs) for genome-wide association requires technologies for generating millions of genotypes with relative ease but also at a reasonable cost and with high accuracy. In this work, we have developed a theoretical approach to estimate allele frequency in pooled DNA samples, based on the physical principles of DNA immobilization and hybridization on solid surface using the Langmuir kinetic model and quantitative analysis of the allelic signals. Results This method can successfully distinguish allele frequencies differing by 0.01 in the actual pool of clinical samples, and detect alleles with a frequency as low as 2%. The accuracy of measuring known allele frequencies is very high, with the strength of correlation between measured and actual frequencies having an r2 = 0.9992. These results demonstrated that this method could allow the accurate estimation of absolute allele frequencies in pooled samples of DNA in a feasible and inexpensive way. Conclusion We conclude that this novel strategy for quantitative analysis of the ratio of SNP allelic sequences in DNA pools is an inexpensive and feasible alternative for detecting polymorphic differences in candidate gene association studies and genome-wide linkage disequilibrium scans. PMID:19087310

  6. Male dominance rarely skews the frequency distribution of Y chromosome haplotypes in human populations

    PubMed Central

    Lansing, J. Stephen; Watkins, Joseph C.; Hallmark, Brian; Cox, Murray P.; Karafet, Tatiana M.; Sudoyo, Herawati; Hammer, Michael F.

    2008-01-01

    A central tenet of evolutionary social science holds that behaviors, such as those associated with social dominance, produce fitness effects that are subject to cultural selection. However, evidence for such selection is inconclusive because it is based on short-term statistical associations between behavior and fertility. Here, we show that the evolutionary effects of dominance at the population level can be detected using noncoding regions of DNA. Highly variable polymorphisms on the nonrecombining portion of the Y chromosome can be used to trace lines of descent from a common male ancestor. Thus, it is possible to test for the persistence of differential fertility among patrilines. We examine haplotype distributions defined by 12 short tandem repeats in a sample of 1269 men from 41 Indonesian communities and test for departures from neutral mutation-drift equilibrium based on the Ewens sampling formula. Our tests reject the neutral model in only 5 communities. Analysis and simulations show that we have sufficient power to detect such departures under varying demographic conditions, including founder effects, bottlenecks, and migration, and at varying levels of social dominance. We conclude that patrilines seldom are dominant for more than a few generations, and thus traits or behaviors that are strictly paternally inherited are unlikely to be under strong cultural selection. PMID:18703660

  7. Factors affecting the power of haplotype markers in association studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important, unresolved question in genome-wide association studies is whether there are predictable differences in power between single-SNP and haplotype markers. In this study, we use coalescent simulations to compare power for single-SNP and haplotype markers under a number of different models ...

  8. The association of XRCC1 haplotypes and chromosomal damage levels in peripheral blood lymphocyte among coke-oven workers

    SciTech Connect

    Shuguang Leng; Juan Cheng; Linyuan Zhang; Yong Niu; Yufei Dai; Zufei Pan; Bin Li; Fengsheng He; Yuxin Zheng

    2005-05-15

    Theoretically, a haplotype has a higher level of heterozygosity than individual single nucleotide polymorphism (SNP) and the association study based on the haplotype may have an increased power for detecting disease associations compared with SNP-based analysis. In this study, we investigated the effects of four haplotype-tagging SNPs (htSNP) and the inferred haplotype pairs of the X-ray cross-complementing group 1 (XRCC1) gene on chromosome damage detected by the cytokinesis-block micronucleus assay. The study included 141 coke-oven workers with exposure to a high level of polycyclic aromatic hydrocarbons and 66 nonexposed controls. The frequencies of total MN and MNed cells were borderline associated with the Arg{sup 194}Trp polymorphism (P = 0.053 and P = 0.050, respectively) but not associated with the Arg{sup 280}His, Arg{sup 399}Gln and Gln{sup 632}Gln polymorphisms among coke-oven workers. Five haplotypes, including CGGG, TGGG, CAGG, CGAG, and CGGA, were inferred based on the four htSNPs of XRCC1 gene. The haplotype CGGG was associated with the decreased frequencies of total MN and MNed cells, and the haplotypes TGGG and CGAG were associated with the increased frequencies of total MN and MNed cells with adjustment for covariates among coke-oven workers. This study showed that the haplotypes derived from htSNPs in the XRCC1 gene were more likely than single SNPs to correlate with the polycyclic aromatic hydrocarbon-induced chromosome damage among coke-oven workers.

  9. HLA-A, HLA-B and HLA-DRB1 allele and haplotype frequencies of 10 918 Koreans from bone marrow donor registry in Korea.

    PubMed

    Park, H; Lee, Y-J; Song, E Y; Park, M H

    2016-10-01

    The human leucocyte antigen (HLA) system is the most polymorphic genetic system in humans, and HLA matching is crucial in organ transplantation, especially in hematopoietic stem cell transplantation. We investigated HLA-A, HLA-B and HLA-DRB1 allele and haplotype frequencies at allelic level in 10 918 Koreans from bone marrow donor registry in Korea. Intermediate resolution HLA typing was performed using Luminex technology (Wakunaga, Japan), and additional allelic level typing was performed using PCR-single-strand conformation polymorphism method and/or sequence-based typing (Abbott Molecular, USA). Allele and haplotype frequencies were calculated by direct counting and maximum likelihood methods, respectively. A total of 39 HLA-A, 66 HLA-B and 47 HLA-DRB1 alleles were identified. High-frequency alleles found at a frequency of ≥5% were 6 HLA-A (A*02:01, *02:06, *11:01, *24:02, *31:01 and *33:03), 6 HLA-B (B*15:01, *35:01, *44:03, *51:01, 54:01 and *58:01) and 8 HLA-DRB1 (DRB1*01:01, *04:05, *04:06, *07:01, *08:03, *09:01, *13:02 and *15:01) alleles. At each locus, A*02, B*15 and DRB1*14 generic groups were most diverse at allelic level, consisting of 9, 12 and 11 different alleles, respectively. A total of 366, 197 and 21 different HLA-A-B-DRB1 haplotypes were estimated with frequencies of ≥0.05%, ≥0.1% and ≥0.5%, respectively. The five most common haplotypes with frequencies of ≥2.0% were A*33:03-B*44:03-DRB1*13:02 (4.97%), A*33:03-B*58:01-DRB1*13:02, A*33:03-B*44:03-DRB1*07:01, A*24:02-B*07:02-DRB1*01:01 and A*24:02-B*52:01-DRB1*15:02. Among 34 serologic HLA-A-B-DR haplotypes with frequencies of ≥0.5%, 17 haplotypes revealed allele-level diversity and majority of the allelic variation was arising from A2, A26, B61, B62, DR4 and DR14 specificities. Haplotype diversity obtained in this study is the most comprehensive data thus far reported in Koreans, and the information will be useful for unrelated stem cell transplantation as well as for disease

  10. The evolution and diversity of TNF block haplotypes in European, Asian and Australian Aboriginal populations.

    PubMed

    Valente, F P; Tan, C R T; Temple, S E; Phipps, M; Witt, C S; Kaur, G; Gut, I; McGinn, S; Allcock, R J N; Chew, C S N; Price, P

    2009-10-01

    The region spanning the tumour necrosis factor (TNF) cluster in the human major histocompatibility complex is implicated in susceptibility to immunopathological disease, but ethnic differences and linkage disequilibrium have hampered identification of critical polymorphisms. Here, we investigate Europeans, Asians (Bidayuh, Chinese, Indian, Jehai, Malay, Temuan) and Australian Aborigines to provide a framework for disease-association studies. DNA from 999 unrelated healthy donors was genotyped at 38 loci, primarily in coding and promoter regions over a 60-kb region spanning seven genes near TNF. The PHASE algorithm was used to statistically infer TNF block haplotypes and estimate their frequencies in each population. The TNF block is carried as 31 haplotypes in all populations combined, with <19 in any single population. Only six haplotypes have a unique tag single nucleotide polymorphism (SNP) valid for all populations, but seven haplotypes could be tagged with individual SNPs in selected populations. Four to eight TNF block haplotypes exist across all ethnicities, and hence must pre-date the divergence of these populations from a common ancestor >160,000 years ago. Some haplotypes are unique to isolated populations, but they do not contain unique SNP. Hence, they reflect restricted migration and/or extinction of some families rather than de novo mutation. PMID:19536152

  11. HLA-G allele and haplotype frequencies in a healthy population of Iran.

    PubMed

    Kuroshli, Zahra; Gourabi, Hamid; Bazrgar, Masoud; Sanati, Mohammad Hossein; Bahraminejad, Elmira; Anisi, Khadije

    2014-06-01

    The human leukocyte antigen (HLA)-G molecule is expressed in cytotrophoblast cells, adult thymic epithelial cells, erythroblasts, pancreatic islets and mesenchymal stem cells. Although, HLA-G expression in allotransplanted patients is correlated with a better allograft acceptance, it is associated with an advanced grade of the tumor in cancer. In addition to the role on the immune system, HLA-G is also involved in successful pregnancy through the embryo implantation, fetal survival and the initial steps of hematopoiesis and angiogenesis. The aim of this study was determination of HLA-G allele frequencies in a healthy population of Iran. In this research, we selected 100 samples from healthy Iranian individuals and henceforth, we used polymerase chain reaction (PCR) followed by sequencing technique for exon 2, 3, 4 and intron 2 of the gene for evaluating the HLA-G alleles frequencies. Investigation of intronic (intron 2) variation is the novelty of our study. The obtained results indicated thirteen alleles of HLA-G in Iranian individuals including G*01:01:01:01, G*01:06, G*01:01:01:06, G*01:01:02, G*01:01:03, G*01:01:05, G*01:01:06, G*01:01:07, G*01:01:08, G*01:03, G*01:04:01, G*01:04:03, and G*01:04:04. According to this study, the most prevalent alleles in the Iranian population were G*01:01:01:01 (52.5%), G*01:01:02 (16%) and G*01:04:03 (14.5%) and also the lowest alleles regarding the frequency were G*01:01:01:06 (0.5%) and G*01:03 (0.5%). The results of G*01:01:01:01 and G*01:04:01 frequencies showed some similarities with the polish population. Our results were similar to the north Indian population for the frequencies of G*01:06 and G*01:01:02. PMID:24659125

  12. High-Resolution Analyses of Human Leukocyte Antigens Allele and Haplotype Frequencies Based on 169,995 Volunteers from the China Bone Marrow Donor Registry Program

    PubMed Central

    Zhou, Xiao-Yang; Zhu, Fa-Ming; Li, Jian-Ping; Mao, Wei; Zhang, De-Mei; Liu, Meng-Li; Hei, Ai-Lian; Dai, Da-Peng; Jiang, Ping; Shan, Xiao-Yan; Zhang, Bo-Wei; Zhu, Chuan-Fu; Shen, Jie; Deng, Zhi-Hui; Wang, Zheng-Lei; Yu, Wei-Jian; Chen, Qiang; Qiao, Yan-Hui; Zhu, Xiang-Ming; Lv, Rong; Li, Guo-Ying; Li, Guo-Liang; Li, Heng-Cong; Zhang, Xu; Pei, Bin; Jiao, Li-Xin; Shen, Gang; Liu, Ying; Feng, Zhi-Hui; Su, Yu-Ping; Xu, Zhao-Xia; Di, Wen-Ying; Jiang, Yao-Qin; Fu, Hong-Lei; Liu, Xiang-Jun; Liu, Xiang; Zhou, Mei-Zhen; Du, Dan; Liu, Qi; Han, Ying; Zhang, Zhi-Xin; Cai, Jian-Ping

    2015-01-01

    Allogeneic hematopoietic stem cell transplantation is a widely used and effective therapy for hematopoietic malignant diseases and numerous other disorders. High-resolution human leukocyte antigen (HLA) haplotype frequency distributions not only facilitate individual donor searches but also determine the probability with which a particular patient can find HLA-matched donors in a registry. The frequencies of the HLA-A, -B, -C, -DRB1, and -DQB1 alleles and haplotypes were estimated among 169,995 Chinese volunteers using the sequencing-based typing (SBT) method. Totals of 191 HLA-A, 244 HLA-B, 146 HLA-C, 143 HLA-DRB1 and 47 HLA-DQB1 alleles were observed, which accounted for 6.98%, 7.06%, 6.46%, 9.11% and 7.91%, respectively, of the alleles in each locus in the world (IMGT 3.16 Release, Apr. 2014). Among the 100 most common haplotypes from the 169,995 individuals, nine distinct haplotypes displayed significant regionally specific distributions. Among these, three were predominant in the South China region (i.e., the 20th, 31st, and 81sthaplotypes), another three were predominant in the Southwest China region (i.e., the 68th, 79th, and 95th haplotypes), one was predominant in the South and Southwest China regions (the 18th haplotype), one was relatively common in the Northeast and North China regions (the 94th haplotype), and one was common in the Northeast, North and Northwest China (the 40th haplotype). In conclusion, this is the first to analyze high-resolution HLA diversities across the entire country of China, based on a detailed and complete data set that covered 31 provinces, autonomous regions, and municipalities. Specifically, we also evaluated the HLA matching probabilities within and between geographic regions and analyzed the regional differences in the HLA diversities in China. We believe that the data presented in this study might be useful for unrelated HLA-matched donor searches, donor registry planning, population genetic studies, and anthropogenesis

  13. Worldwide patterns of haplotype diversity at 9p21.3, a locus associated with type 2 diabetes and coronary heart disease.

    PubMed

    Silander, Kaisa; Tang, Hua; Myles, Sean; Jakkula, Eveliina; Timpson, Nicholas J; Cavalli-Sforza, Luigi; Peltonen, Leena

    2009-01-01

    A 100 kb region on 9p21.3 harbors two major disease susceptibility loci: one for type 2 diabetes (T2D) and one for coronary heart disease (CHD). The single nucleotide polymorphisms (SNPs) associated with these two diseases in Europeans reside on two adjacent haplotype blocks with independent effects on disease. To help delimit the regions that likely harbor the disease-causing variants in populations of non-European origin, we studied the haplotype diversity and allelic history of the 9p21.3 region using 938 unrelated individuals from 51 populations (Human Genome Diversity Panel). We used SNP data from Illumina's 650Y SNP arrays supplemented with five additional SNPs within the region of interest. Haplotype frequencies were analyzed with the EM algorithm implemented in PLINK. For the T2D locus, the TT risk haplotype of SNPs rs10811661 and rs10757283 was present at similar frequencies in all global populations, while a shared 6-SNP haplotype that carries the protective C allele of rs10811661 was found at a frequency of 2.9% in Africans and 41.3% in East Asians and was associated with low haplotype diversity. For the CHD locus, all populations shared a core risk haplotype spanning >17.5 kb, which shows dramatic increase in frequency between African (11.5%) and Middle Eastern (63.7%) populations. Interestingly, two SNPs (rs2891168 and rs10757278) tagging this CHD risk haplotype are most strongly associated with CHD disease status according to independent clinical fine-mapping studies. The large variation in linkage disequilibrium patterns identified between the populations demonstrates the importance of allelic background data when selecting SNPs for replication in global populations. Intriguingly, the protective allele for T2D and the risk allele for CHD show an increase in frequency in non-Africans compared to Africans, implying different population histories for these two adjacent disease loci. PMID:19463184

  14. Discovery of high frequencies of the Gly-Ile haplotype of TLR4 in Indian populations requires reformulation of the evolutionary model of its maintenance.

    PubMed

    Mukherjee, Souvik; Ganguli, Debdutta; Majumder, Partha P

    2013-10-01

    The Out-of-Africa migration of modern humans has led to the evolution of immunity genes in general, particularly those related to direct host-pathogen interactions. The Toll-like receptor 4 (TLR4) is one such cell-surface pattern recognition receptor that has been associated with susceptibility and resistance to Gram-negative infections. In this report, we have studied the genetic variation in the TLR4 gene across pre- and post-agricultural populations in India. Two non-synonymous SNPs at the loci Asp299Gly and Thr399Ile are genotyped in 266 individuals from these populations. Previous studies have shown that specific alleles at these two loci are associated with inflammatory response and also claimed the complete absence of the Gly-Ile (double-mutated) haplotype in populations from Asia and America due to some evolutionary disadvantage owing to septic shock. Contrary to such claims, our study reports for the first time, high (10%) to moderate (3-6%) frequencies of the Gly-Ile haplotype in one non-tribal and two tribal populations of India respectively. The presence of this haplotype in ancient tribal populations of India indicates the possibility of its important role in pathogen recognition or susceptibility to infections. Therefore, natural selection, not merely genetic drift, may have played an important role in shaping the frequency distribution of haplotypes at these two loci in TLR4. For a more global perspective, we have also estimated the frequency of this haplotype in all the 14 continental populations included in the 1000 Genomes Project. Our study provides direct evidence for the reformulation of existing models of evolutionary maintenance of these polymorphisms in the TLR4 gene. PMID:23892373

  15. Coding region SNP analysis to enhance dog mtDNA discrimination power in forensic casework.

    PubMed

    Verscheure, Sophie; Backeljau, Thierry; Desmyter, Stijn

    2015-01-01

    The high population frequencies of three control region haplotypes contribute to the low discrimination power of the dog mtDNA control region. It also diminishes the evidential power of a match with one of these haplotypes in forensic casework. A mitochondrial genome study of 214 Belgian dogs suggested 26 polymorphic coding region sites that successfully resolved dogs with the three most frequent control region haplotypes. In this study, three SNP assays were developed to determine the identity of the 26 informative sites. The control region of 132 newly sampled dogs was sequenced and added to the study of 214 dogs. The assays were applied to 58 dogs of the haplotypes of interest, which confirmed their suitability for enhancing dog mtDNA discrimination power. In the Belgian population study of 346 dogs, the set of 26 sites divided the dogs into 25 clusters of mtGenome sequences with substantially lower population frequency estimates than their control region sequences. In case of a match with one of the three control region haplotypes, using these three SNP assays in conjunction with control region sequencing would augment the exclusion probability of dog mtDNA analysis from 92.9% to 97.0%. PMID:25299153

  16. Inferring the Joint Demographic History of Multiple Populations from Multidimensional SNP Frequency Data

    PubMed Central

    Gutenkunst, Ryan N.; Hernandez, Ryan D.; Williamson, Scott H.; Bustamante, Carlos D.

    2009-01-01

    Demographic models built from genetic data play important roles in illuminating prehistorical events and serving as null models in genome scans for selection. We introduce an inference method based on the joint frequency spectrum of genetic variants within and between populations. For candidate models we numerically compute the expected spectrum using a diffusion approximation to the one-locus, two-allele Wright-Fisher process, involving up to three simultaneous populations. Our approach is a composite likelihood scheme, since linkage between neutral loci alters the variance but not the expectation of the frequency spectrum. We thus use bootstraps incorporating linkage to estimate uncertainties for parameters and significance values for hypothesis tests. Our method can also incorporate selection on single sites, predicting the joint distribution of selected alleles among populations experiencing a bevy of evolutionary forces, including expansions, contractions, migrations, and admixture. We model human expansion out of Africa and the settlement of the New World, using 5 Mb of noncoding DNA resequenced in 68 individuals from 4 populations (YRI, CHB, CEU, and MXL) by the Environmental Genome Project. We infer divergence between West African and Eurasian populations 140 thousand years ago (95% confidence interval: 40–270 kya). This is earlier than other genetic studies, in part because we incorporate migration. We estimate the European (CEU) and East Asian (CHB) divergence time to be 23 kya (95% c.i.: 17–43 kya), long after archeological evidence places modern humans in Europe. Finally, we estimate divergence between East Asians (CHB) and Mexican-Americans (MXL) of 22 kya (95% c.i.: 16.3–26.9 kya), and our analysis yields no evidence for subsequent migration. Furthermore, combining our demographic model with a previously estimated distribution of selective effects among newly arising amino acid mutations accurately predicts the frequency spectrum of

  17. HaplotypeCN: copy number haplotype inference with Hidden Markov Model and localized haplotype clustering.

    PubMed

    Lin, Yen-Jen; Chen, Yu-Tin; Hsu, Shu-Ni; Peng, Chien-Hua; Tang, Chuan-Yi; Yen, Tzu-Chen; Hsieh, Wen-Ping

    2014-01-01

    Copy number variation (CNV) has been reported to be associated with disease and various cancers. Hence, identifying the accurate position and the type of CNV is currently a critical issue. There are many tools targeting on detecting CNV regions, constructing haplotype phases on CNV regions, or estimating the numerical copy numbers. However, none of them can do all of the three tasks at the same time. This paper presents a method based on Hidden Markov Model to detect parent specific copy number change on both chromosomes with signals from SNP arrays. A haplotype tree is constructed with dynamic branch merging to model the transition of the copy number status of the two alleles assessed at each SNP locus. The emission models are constructed for the genotypes formed with the two haplotypes. The proposed method can provide the segmentation points of the CNV regions as well as the haplotype phasing for the allelic status on each chromosome. The estimated copy numbers are provided as fractional numbers, which can accommodate the somatic mutation in cancer specimens that usually consist of heterogeneous cell populations. The algorithm is evaluated on simulated data and the previously published regions of CNV of the 270 HapMap individuals. The results were compared with five popular methods: PennCNV, genoCN, COKGEN, QuantiSNP and cnvHap. The application on oral cancer samples demonstrates how the proposed method can facilitate clinical association studies. The proposed algorithm exhibits comparable sensitivity of the CNV regions to the best algorithm in our genome-wide study and demonstrates the highest detection rate in SNP dense regions. In addition, we provide better haplotype phasing accuracy than similar approaches. The clinical association carried out with our fractional estimate of copy numbers in the cancer samples provides better detection power than that with integer copy number states. PMID:24849202

  18. Evaluating the Feasibility of Fitting Haplotype Effects as Random: Variance Component Estimation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fitting haplotypes as random effects in association studies may prevent overestimation of haplotypic effects with low frequencies. The objective was to determine whether haplotypic variance could be accurately estimated. Using simulation, haplotypic effects were deterministically assigned to eithe...

  19. Frequency and origin of haplotypes associated with the beta-globin gene cluster in individuals with trait and sickle cell anemia in the Atlantic and Pacific coastal regions of Colombia.

    PubMed

    Fong, Cristian; Lizarralde-Iragorri, María Alejandra; Rojas-Gallardo, Diana; Barreto, Guillermo

    2013-12-01

    Sickle cell anemia is a genetic disease with high prevalence in people of African descent. There are five typical haplotypes associated with this disease and the haplotypes associated with the beta-globin gene cluster have been used to establish the origin of African-descendant people in America. In this work, we determined the frequency and the origin of haplotypes associated with hemoglobin S in a sample of individuals with sickle cell anemia (HbSS) and sickle cell hemoglobin trait (HbAS) in coastal regions of Colombia. Blood samples from 71 HbAS and 79 HbSS individuals were obtained. Haplotypes were determined based on the presence of variable restriction sites within the β-globin gene cluster. On the Pacific coast of Colombia the most frequent haplotype was Benin, while on the Atlantic coast Bantu was marginally higher than Benin. Eight atypical haplotypes were observed on both coasts, being more diverse in the Atlantic than in the Pacific region. These results suggest a differential settlement of the coasts, dependent on where slaves were brought from, either from the Gulf of Guinea or from Angola, where the haplotype distributions are similar. Atypical haplotypes probably originated from point mutations that lost or gained a restriction site and/or by recombination events. PMID:24385850

  20. SOD2 V16A SNP in the Mitochondrial Targeting Sequence is Associated with Noise Induced Hearing Loss in Chinese Workers

    PubMed Central

    Liu, Yi-Min; Li, Xu-Dong; Guo, Xiao; Liu, Bin; Lin, Ai-Hua; Ding, Yuan-Lin; Rao, Shao-Qi

    2010-01-01

    Objective: To investigate whether single nucleotide polymorphisms (SNPs) in the Mn-superoxide dismutase gene (SOD2) underlie the susceptibility to noise-induced hearing loss (NIHL). Methods: Audiometric data from 2400 Chinese Han workers who exposed to occupational noise were analyzed. DNA samples were collected from the 10% most susceptible and the 10% most resistant individuals, and five SNPs (SOD2 rs2842980, rs5746136, rs2758331, rs4880 and rs5746092) were genotyped by Taqman SNP Genotyping Kits. The SNP main effects and interactions between noise exposure and SNP were analyzed using logistic regression. Haplotypes were analyzed by using Haploview software. Results: The CT genotype of rs4880 (SOD2 V16A SNP) was associated with a higher risk of NIHL (covariates-adjusted OR, 2.18; 95% CI, 1.34–3.54, P = 0.002). Haplotype analysis revealed that the frequency of AGCCG at the five SNP loci was significantly higher in the susceptible group (P = 0.020). With AGCTG as the reference, the OR (95% CI) was 2.63 (1.14, 6.06). The rs4880 polymorphisms imposed larger effects when the carriers were exposed to higher levels of noise, indicating the interaction between SNP and noise exposure. Conclusions: Our results suggest that SOD2 V16A SNP in the mitochondrial targeting sequence is associated with noise induced hearing loss in Chinese workers, and this effect was enhanced by higher levels of noise exposure. PMID:20534900

  1. Haplotype frequencies for 17 Y-STR loci (AmpFlSTRY-filer) in a Moroccan population sample.

    PubMed

    Aboukhalid, Rachid; Bouabdellah, Mehdi; Abbassi, Meriame; Bentayebi, Kaoutar; Elmzibri, Mohammed; Squalli, Driss; Amzazi, Saaïd

    2010-04-01

    A sample of 267 unrelated Moroccan males from different ethnic groups (Arabs, Berbers and Sahrawi), was typed for 17 Y-STR loci (DYS19, DYS385, DYS389 I, DYS389 II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, Y GATA H4). Discrimination capacity (96.3%) and haplotype diversity (99.91%) were calculated. A total of 257 haplotypes were identified, of which 237 were unique and 10 were found in two individuals each. DYS385 showed the highest diversity (0.887) followed by DYS458 (0.820) as a single locus marker. PMID:20215021

  2. Concurrent Whole-Genome Haplotyping and Copy-Number Profiling of Single Cells

    PubMed Central

    Zamani Esteki, Masoud; Dimitriadou, Eftychia; Mateiu, Ligia; Melotte, Cindy; Van der Aa, Niels; Kumar, Parveen; Das, Rakhi; Theunis, Koen; Cheng, Jiqiu; Legius, Eric; Moreau, Yves; Debrock, Sophie; D’Hooghe, Thomas; Verdyck, Pieter; De Rycke, Martine; Sermon, Karen; Vermeesch, Joris R.; Voet, Thierry

    2015-01-01

    Methods for haplotyping and DNA copy-number typing of single cells are paramount for studying genomic heterogeneity and enabling genetic diagnosis. Before analyzing the DNA of a single cell by microarray or next-generation sequencing, a whole-genome amplification (WGA) process is required, but it substantially distorts the frequency and composition of the cell’s alleles. As a consequence, haplotyping methods suffer from error-prone discrete SNP genotypes (AA, AB, BB) and DNA copy-number profiling remains difficult because true DNA copy-number aberrations have to be discriminated from WGA artifacts. Here, we developed a single-cell genome analysis method that reconstructs genome-wide haplotype architectures as well as the copy-number and segregational origin of those haplotypes by employing phased parental genotypes and deciphering WGA-distorted SNP B-allele fractions via a process we coin haplarithmisis. We demonstrate that the method can be applied as a generic method for preimplantation genetic diagnosis on single cells biopsied from human embryos, enabling diagnosis of disease alleles genome wide as well as numerical and structural chromosomal anomalies. Moreover, meiotic segregation errors can be distinguished from mitotic ones. PMID:25983246

  3. SNP genotyping by heteroduplex analysis.

    PubMed

    Paniego, Norma; Fusari, Corina; Lia, Verónica; Puebla, Andrea

    2015-01-01

    Heteroduplex-based genotyping methods have proven to be technologically effective and economically efficient for low- to medium-range throughput single-nucleotide polymorphism (SNP) determination. In this chapter we describe two protocols that were successfully applied for SNP detection and haplotype analysis of candidate genes in association studies. The protocols involve (1) enzymatic mismatch cleavage with endonuclease CEL1 from celery, associated with fragment separation using capillary electrophoresis (CEL1 cleavage), and (2) differential retention of the homo/heteroduplex DNA molecules under partial denaturing conditions on ion pair reversed-phase liquid chromatography (dHPLC). Both methods are complementary since dHPLC is more versatile than CEL1 cleavage for identifying multiple SNP per target region, and the latter is easily optimized for sequences with fewer SNPs or small insertion/deletion polymorphisms. Besides, CEL1 cleavage is a powerful method to localize the position of the mutation when fragment resolution is done using capillary electrophoresis. PMID:25373754

  4. Diversity of Extended HLA-DRB1 Haplotypes in the Finnish Population

    PubMed Central

    Wennerström, Annika; Vlachopoulou, Efthymia; Lahtela, L. Elisa; Paakkanen, Riitta; Eronen, Katja T.; Seppänen, Mikko; Lokki, Marja-Liisa

    2013-01-01

    The Major Histocompatibility Complex (MHC, 6p21) codes for traditional HLA and other host response related genes. The polymorphic HLA-DRB1 gene in MHC Class II has been associated with several complex diseases. In this study we focus on MHC haplotype structures in the Finnish population. We explore the variability of extended HLA-DRB1 haplotypes in relation to the other traditional HLA genes and a selected group of MHC class III genes. A total of 150 healthy Finnish individuals were included in the study. Subjects were genotyped for HLA alleles (HLA-A, -B, -DRB1, -DQB1, and -DPB1). The polymorphism of TNF, LTA, C4, BTNL2 and HLA-DRA genes was studied with 74 SNPs (single nucleotide polymorphism). The C4A and C4B gene copy numbers and a 2-bp silencing insertion at exon 29 in C4A gene were analysed with quantitative genomic realtime-PCR. The allele frequencies for each locus were calculated and haplotypes were constructed using both the traditional HLA alleles and SNP blocks. The most frequent Finnish A∼B∼DR -haplotype, uncommon in elsewhere in Europe, was A*03∼B*35∼DRB1*01∶01. The second most common haplotype was a common European ancestral haplotype AH 8.1 (A*01∼B*08∼DRB1*03∶01). Extended haplotypes containing HLA-B, TNF block, C4 and HLA-DPB1 strongly increased the number of HLA-DRB1 haplotypes showing variability in the extended HLA-DRB1 haplotype structures. On the contrary, BTNL2 block and HLA-DQB1 were more conserved showing linkage with the HLA-DRB1 alleles. We show that the use of HLA-DRB1 haplotypes rather than single HLA-DRB1 alleles is advantageous when studying the polymorphisms and LD patters of the MHC region. For disease association studies the HLA-DRB1 haplotypes with various MHC markers allows us to cluster haplotypes with functionally important gene variants such as C4 deficiency and cytokines TNF and LTA, and provides hypotheses for further assessment. Our study corroborates the importance of studying population-specific MHC

  5. Diversity of extended HLA-DRB1 haplotypes in the Finnish population.

    PubMed

    Wennerström, Annika; Vlachopoulou, Efthymia; Lahtela, L Elisa; Paakkanen, Riitta; Eronen, Katja T; Seppänen, Mikko; Lokki, Marja-Liisa

    2013-01-01

    The Major Histocompatibility Complex (MHC, 6p21) codes for traditional HLA and other host response related genes. The polymorphic HLA-DRB1 gene in MHC Class II has been associated with several complex diseases. In this study we focus on MHC haplotype structures in the Finnish population. We explore the variability of extended HLA-DRB1 haplotypes in relation to the other traditional HLA genes and a selected group of MHC class III genes. A total of 150 healthy Finnish individuals were included in the study. Subjects were genotyped for HLA alleles (HLA-A, -B, -DRB1, -DQB1, and -DPB1). The polymorphism of TNF, LTA, C4, BTNL2 and HLA-DRA genes was studied with 74 SNPs (single nucleotide polymorphism). The C4A and C4B gene copy numbers and a 2-bp silencing insertion at exon 29 in C4A gene were analysed with quantitative genomic realtime-PCR. The allele frequencies for each locus were calculated and haplotypes were constructed using both the traditional HLA alleles and SNP blocks. The most frequent Finnish A∼B∼DR -haplotype, uncommon in elsewhere in Europe, was A*03∼B*35∼DRB1*01∶01. The second most common haplotype was a common European ancestral haplotype AH 8.1 (A*01∼B*08∼DRB1*03∶01). Extended haplotypes containing HLA-B, TNF block, C4 and HLA-DPB1 strongly increased the number of HLA-DRB1 haplotypes showing variability in the extended HLA-DRB1 haplotype structures. On the contrary, BTNL2 block and HLA-DQB1 were more conserved showing linkage with the HLA-DRB1 alleles. We show that the use of HLA-DRB1 haplotypes rather than single HLA-DRB1 alleles is advantageous when studying the polymorphisms and LD patters of the MHC region. For disease association studies the HLA-DRB1 haplotypes with various MHC markers allows us to cluster haplotypes with functionally important gene variants such as C4 deficiency and cytokines TNF and LTA, and provides hypotheses for further assessment. Our study corroborates the importance of studying population-specific MHC

  6. Haplotype frequencies of 17 Y-chromosomal short tandem repeat loci from the Cukurova region of Turkey

    PubMed Central

    Serin, Ayse; Canan, Husniye; Alper, Behnan; Sertdemir, Yasar

    2011-01-01

    Aim To investigate the distribution of 17 Y-short tandem repeat (STR) loci in the population of the Cukurova region of Turkey. Methods In the period between 2009 and 2010, we investigated the distribution of 17 Y-STRs in a sample of 249 unrelated healthy men from the Cukurova region of Turkey. Genomic DNA was extracted with InstaGene matrix and Y-STRs were determined using the AmpFISTR Yfiler PCR amplification kit. Gene and haplotype diversity values were estimated using the Arlequin software. To compare our data to other populations, population pairwise genetic distances and associated probability values were calculated using the Y Chromosome Haplotype Reference Database Web site software. Results At 17 Y-STR loci we detected 148 alleles. The lowest gene diversity in this region was 0.51 for DYS391 and the highest 0.95 for DYS385a/b. Haplotype diversity was 0.9997 ± 0.0004. We compared our data with haplotype data of other Turkish populations and no significant differences were found, except with Ankara population (Φst = 0.025, P = 0.018). Comparisons were also made with the neighboring populations using analysis of molecular variance of the Y-STR loci genetic structure and our population was nearest to Lenkoran-Azerbaijani (Φst = 0.012, P = 0.068) and Iranian Ahvaz population (Φst = 0.007, P = 0.173), followed by Greek (Φst = 0.026, P = 0.000) and Russian (Φst = 0.048, P = 0.000) population. Other countries like Portugal, Spain, Italy, Egypt, Israel (Palestinian Authority Area), and Taiwan showed a high genetic distance from our population. Conclusion Our study showed that Y-STR polymorphisms were a powerful discrimination tool for routine forensic applications and could be used in genealogical investigations. PMID:22180269

  7. Analysis of HLA class I-II haplotype frequency and segregation in a cohort of patients with advanced stage ovarian cancer.

    PubMed

    Gamzatova, Z; Villabona, L; van der Zanden, H; Haasnoot, G W; Andersson, E; Kiessling, R; Seliger, B; Kanter, L; Dalianis, T; Bergfeldt, K; Masucci, G V

    2007-09-01

    In solid tumors, human leucocyte antigen (HLA)-A2 has been suggested to be a risk factor and a negative prognostic factor. The HLA-A2 allele in Scandinavia has a high prevalence; it decreases with latitude and also with ovarian cancer mortality in Europe. Furthermore, an association of the HLA-A2 allele with severe prognosis in serous adenocarcinoma of the ovary in stages III-IV was found. Thirty-two unrelated Swedish women with relapsing or progressive ovarian cancer were analysed for the genotypes at the HLA-A, HLA-B, HLA-Cw, and HLA-DRB1 loci by the polymerase chain reaction/sequence-specific primer method. The frequencies of HLA alleles of healthy Swedish bone marrow donors provided by the coordinating centre of the Bone Marrow Donors Worldwide Registries, Leiden, the Netherlands were used as controls. When this cohort of epithelial ovarian cancer patients was compared with healthy Swedish donors, the frequency of HLA-A1 and HLA-A2 gene/phenotype appears, although not statistically significant, to be increased in patients with ovarian carcinoma, while HLA-A3 was decreased. HLA-A2 homozygotes were twofold higher in patients. The A2-B8 haplotype was significantly increased (corrected P value). A2-B5, A2-B15, A2-DRB1*03, A2-DRB1*04, A2-B15-Cw3, and A2-B8-DRB1*03 had odds ratio as well as the level of the lower confidence interval above 1 and significant P value only when considered as single, non-corrected analysis. HLA-B15 and HLA-Cw3 were only present in HLA-A2-positive patients showing that the HLA-A2-HLA-Cw3 and HLA-B15 haplotypes were segregated. In this selected cohort with advanced disease, there are indications of an unusual overrepresentation of HLA class I and II genes/haplotypes as well as segregation for the HLA-A2-HLA-Cw3 and HLA-B15 haplotypes. These findings are presented as a descriptive analysis and need further investigations on a larger series of ovarian cancer patients to establish prognostic associations. PMID:17661908

  8. µ-Calpain, calpastatin, and growth hormone receptor genetic effects on preweaning performance, carcass quality traits, and residual variance of tenderness in Angus cattle selected to increase minor haplotype ... frequencies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic marker effects and interactions are estimated with poor precision when minor marker allele frequencies are low. An Angus population was subjected to marker assisted selection for multiple years to increase divergent haplotype and minor marker allele frequencies to 1) estimate effect size an...

  9. Frequency of HLA-DRB1 and HLA-DQB1 Alleles and Haplotype Association in Syrian Population.

    PubMed

    Jazairi, Batoul; Khansaa, Issam; Ikhtiar, Adnan; Murad, Hossam

    2016-02-01

    The study of Human Leukocyte Antigen (HLA) system is very important in health and diseases. As the HLA loci are the most polymorphic in the human genome, it plays a very important role in the immune responses to self and nonself antigens. In the light of the growing importance of typing the HLA alleles in transplantation, autoimmune diseases, cancer, and many other diseases, we studied 225 unrelated healthy Syrian subjects for their HLA class II genotypes in an attempt to reveal the distribution of the HLA (DRB1-DQB1) alleles in the general Syrian population. Our results revealed that the most common alleles for the DRB1 locus were DRB1*11 (26.4%), DRB1*04 (14%), and DRB1*07 (12%). However, the most frequent alleles for the DQB1 locus were DQB1*03 (40.9%) and DQB1*05 (25.1%). The frequent of two-locus haplotypes carry the most frequent alleles at these loci. The most frequently detected class II ''haplotypes'' are DRB1*11-DQB1*03 (8.9%), DRB1*01-DQB1*05 (3.6%), and DRB1*04-DQB1*03 (2.7%). Compared with other populations, our result, deduced from the analysis of genetic distances and the construction of neighbor-joining (NJ) dendrogram, and principal component analysis (PCA) indicates that Syrians are related to Middle Eastern populations. Our data about the Syrian population will aid researchers in studying the relation of HLA class II with different diseases in a Syrian population and will add to the available international literature associated with these loci. PMID:26853713

  10. Whole-genome resequencing of two elite sires for the detection of haplotypes under selection in dairy cattle.

    PubMed

    Larkin, Denis M; Daetwyler, Hans D; Hernandez, Alvaro G; Wright, Chris L; Hetrick, Lorie A; Boucek, Lisa; Bachman, Sharon L; Band, Mark R; Akraiko, Tatsiana V; Cohen-Zinder, Miri; Thimmapuram, Jyothi; Macleod, Iona M; Harkins, Timothy T; McCague, Jennifer E; Goddard, Michael E; Hayes, Ben J; Lewin, Harris A

    2012-05-15

    Using a combination of whole-genome resequencing and high-density genotyping arrays, genome-wide haplotypes were reconstructed for two of the most important bulls in the history of the dairy cattle industry, Pawnee Farm Arlinda Chief ("Chief") and his son Walkway Chief Mark ("Mark"), each accounting for ∼7% of all current genomes. We aligned 20.5 Gbp (∼7.3× coverage) and 37.9 Gbp (∼13.5× coverage) of the Chief and Mark genomic sequences, respectively. More than 1.3 million high-quality SNPs were detected in Chief and Mark sequences. The genome-wide haplotypes inherited by Mark from Chief were reconstructed using ∼1 million informative SNPs. Comparison of a set of 15,826 SNPs that overlapped in the sequence-based and BovineSNP50 SNPs showed the accuracy of the sequence-based haplotype reconstruction to be as high as 97%. By using the BovineSNP50 genotypes, the frequencies of Chief alleles on his two haplotypes then were determined in 1,149 of his descendants, and the distribution was compared with the frequencies that would be expected assuming no selection. We identified 49 chromosomal segments in which Chief alleles showed strong evidence of selection. Candidate polymorphisms for traits that have been under selection in the dairy cattle population then were identified by referencing Chief's DNA sequence within these selected chromosome blocks. Eleven candidate genes were identified with functions related to milk-production, fertility, and disease-resistance traits. These data demonstrate that haplotype reconstruction of an ancestral proband by whole-genome resequencing in combination with high-density SNP genotyping of descendants can be used for rapid, genome-wide identification of the ancestor's alleles that have been subjected to artificial selection. PMID:22529356

  11. Whole-genome resequencing of two elite sires for the detection of haplotypes under selection in dairy cattle

    PubMed Central

    Larkin, Denis M.; Daetwyler, Hans D.; Hernandez, Alvaro G.; Wright, Chris L.; Hetrick, Lorie A.; Boucek, Lisa; Bachman, Sharon L.; Band, Mark R.; Akraiko, Tatsiana V.; Cohen-Zinder, Miri; Thimmapuram, Jyothi; Macleod, Iona M.; Harkins, Timothy T.; McCague, Jennifer E.; Goddard, Michael E.; Hayes, Ben J.; Lewin, Harris A.

    2012-01-01

    Using a combination of whole-genome resequencing and high-density genotyping arrays, genome-wide haplotypes were reconstructed for two of the most important bulls in the history of the dairy cattle industry, Pawnee Farm Arlinda Chief (“Chief”) and his son Walkway Chief Mark (“Mark”), each accounting for ∼7% of all current genomes. We aligned 20.5 Gbp (∼7.3× coverage) and 37.9 Gbp (∼13.5× coverage) of the Chief and Mark genomic sequences, respectively. More than 1.3 million high-quality SNPs were detected in Chief and Mark sequences. The genome-wide haplotypes inherited by Mark from Chief were reconstructed using ∼1 million informative SNPs. Comparison of a set of 15,826 SNPs that overlapped in the sequence-based and BovineSNP50 SNPs showed the accuracy of the sequence-based haplotype reconstruction to be as high as 97%. By using the BovineSNP50 genotypes, the frequencies of Chief alleles on his two haplotypes then were determined in 1,149 of his descendants, and the distribution was compared with the frequencies that would be expected assuming no selection. We identified 49 chromosomal segments in which Chief alleles showed strong evidence of selection. Candidate polymorphisms for traits that have been under selection in the dairy cattle population then were identified by referencing Chief’s DNA sequence within these selected chromosome blocks. Eleven candidate genes were identified with functions related to milk-production, fertility, and disease-resistance traits. These data demonstrate that haplotype reconstruction of an ancestral proband by whole-genome resequencing in combination with high-density SNP genotyping of descendants can be used for rapid, genome-wide identification of the ancestor’s alleles that have been subjected to artificial selection. PMID:22529356

  12. Association of TERC and OBFC1 Haplotypes with Mean Leukocyte Telomere Length and Risk for Coronary Heart Disease

    PubMed Central

    Maubaret, Cécilia G.; Salpea, Klelia D.; Romanoski, Casey E.; Folkersen, Lasse; Cooper, Jackie A.; Stephanou, Coralea; Wah Li, Ka; Palmen, Jutta; Hamsten, Anders; Neil, Andrew; Stephens, Jeffrey W.; Lusis, Aldons J.; Eriksson, Per; Talmud, Philippa J.; Humphries, Steve E.

    2013-01-01

    Objective To replicate the associations of leukocyte telomere length (LTL) with variants at four loci and to investigate their associations with coronary heart disease (CHD) and type II diabetes (T2D), in order to examine possible causal effects of telomere maintenance machinery on disease aetiology. Methods Four SNPs at three loci BICD1 (rs2630578 GγC), 18q12.2 (rs2162440 GγT), and OBFC1 (rs10786775 CγG, rs11591710 AγC) were genotyped in four studies comprised of 2353 subjects out of which 1148 had CHD and 566 T2D. Three SNPs (rs12696304 CγG, rs10936601G>T and rs16847897 GγC) at the TERC locus were genotyped in these four studies, in addition to an offspring study of 765 healthy students. For all samples, LTL had been measured using a real-time PCR-based method. Results Only one SNP was associated with a significant effect on LTL, with the minor allele G of OBFC1 rs10786775 SNP being associated with longer LTL (β=0.029, P=0.04). No SNPs were significantly associated with CHD or T2D. For OBFC1 the haplotype carrying both rare alleles (rs10786775G and rs11591710C, haplotype frequency 0.089) was associated with lower CHD prevalence (OR: 0.77; 95% CI: 0.61–0.97; P= 0.03). The TERC haplotype GTC (rs12696304G, rs10936601T and rs16847897C, haplotype frequency 0.210) was associated with lower risk for both CHD (OR: 0.86; 95% CI: 0.75-0.99; P=0.04) and T2D (OR: 0.74; 95% CI: 0.61–0.91; P= 0.004), with no effect on LTL. Only the last association remained after adjusting for multiple testing. Conclusion Of reported associations, only that between the OBFC1 rs10786775 SNP and LTL was confirmed, although our study has a limited power to detect modest effects. A 2-SNP OBFC1 haplotype was associated with higher risk of CHD, and a 3-SNP TERC haplotype was associated with both higher risk of CHD and T2D. Further work is required to confirm these results and explore the mechanisms of these effects. PMID:24349443

  13. TUMOR HAPLOTYPE ASSEMBLY ALGORITHMS FOR CANCER GENOMICS

    PubMed Central

    AGUIAR, DEREK; WONG, WENDY S.W.; ISTRAIL, SORIN

    2014-01-01

    The growing availability of inexpensive high-throughput sequence data is enabling researchers to sequence tumor populations within a single individual at high coverage. But, cancer genome sequence evolution and mutational phenomena like driver mutations and gene fusions are difficult to investigate without first reconstructing tumor haplotype sequences. Haplotype assembly of single individual tumor populations is an exceedingly difficult task complicated by tumor haplotype heterogeneity, tumor or normal cell sequence contamination, polyploidy, and complex patterns of variation. While computational and experimental haplotype phasing of diploid genomes has seen much progress in recent years, haplotype assembly in cancer genomes remains uncharted territory. In this work, we describe HapCompass-Tumor a computational modeling and algorithmic framework for haplotype assembly of copy number variable cancer genomes containing haplotypes at different frequencies and complex variation. We extend our polyploid haplotype assembly model and present novel algorithms for (1) complex variations, including copy number changes, as varying numbers of disjoint paths in an associated graph, (2) variable haplotype frequencies and contamination, and (3) computation of tumor haplotypes using simple cycles of the compass graph which constrain the space of haplotype assembly solutions. The model and algorithm are implemented in the software package HapCompass-Tumor which is available for download from http://www.brown.edu/Research/Istrail_Lab/. PMID:24297529

  14. HLA-A, -B, -C, -DRB1 and -DQB1 allele and haplotype frequencies in a population of 432 healthy unrelated individuals from Albania.

    PubMed

    Sulcebe, Genc; Shyti, Erkena

    2016-08-01

    This paper reports the HLA-A, -B, -C, -DRB1 and -DQB1 allele and haplotype polymorphism in a population of 432 healthy individuals from Albania. First-field HLA genotyping was performed by polymerase chain reaction sequence-specific priming and/or oligonucleotide methods. The data were analyzed statistically using gene counting and Arlequin software packages. No deviation from Hardy Weinberg Equilibrium was detected at any of the loci studied. The HLA genotypic data of the population sample reported here are available publicly in the Allele Frequencies Net Database and they can serve as a reference database for further HLA-based population genetics studies including the Albanian population. PMID:27262454

  15. HLA-A, B and DRB1 allele and haplotype frequencies in volunteer bone marrow donors from the north of Parana State

    PubMed Central

    Bardi, Marlene Silva; Jarduli, Luciana Ribeiro; Jorge, Adylson Justino; Camargo, Rossana Batista Oliveira Godoy; Carneiro, Fernando Pagotto; Gelinski, Jair Roberto; Silva, Roseclei Assunção Feliciano; Lavado, Edson Lopes

    2012-01-01

    Background Knowledge of allele and haplotype frequencies of the human leukocyte antigen (HLA) system is important in the search for unrelated bone marrow donors. The Brazilian population is very heterogeneous and the HLA system is highly informative of populations because of the high level of polymorphisms. Aim The aim of this study was to characterize the immunogenetic profile of ethnic groups (Caucasians, Afro-Brazilians and Asians) in the north of Parana State. Methods A study was carried out of 3978 voluntary bone marrow donors registered in the Brazilian National Bone Marrow Donor Registry and typed for the HLA-A, B and DRB1 (low resolution) loci. The alleles were characterized by the polymerase chain reaction sequence-specific oligonucleotides method using the LabType SSO kit (One Lambda, CA, USA). The ARLEQUIN v.3.11 computer program was used to calculate allele and haplotype frequencies Results The most common alleles found in Caucasians were HLA-A*02, 24, 01; HLA-B*35, 44, 51; DRB1*11, 13, 07; for Afro-Brazilians they were HLA-A*02, 03, 30; HLA-B*35, 15, 44; DRB1*13, 11, 03; and for Asians they were: HLA-A*24, 02, 26; HLA-B*40, 51, 52; DRB1*04, 15, 09. The most common haplotype combinations were: HLA-A*01, B*08, DRB1*03 and HLA-A*29, B*44, DRB1*07 for Caucasians; HLA-A*29, B*44, DRB1*07 and HLA-A*01, B*08 and DRB1*03 for Afro-Brazilians; and HLA-A*24, B*52, DRB1*15 and HLA-A*24, B*40 and DRB1*09 for Asians. Conclusion There is a need to target and expand bone marrow donor campaigns in the north of Parana State. The data of this study may be used as a reference by the Instituto Nacional de Cancer/Brazilian National Bone Marrow Donor Registry to evaluate the immunogenetic profile of populations in specific regions and in the selection of bone marrow donors PMID:23049380

  16. Single Nucleotide Polymorphism (SNP) in the Adiponectin Gene and Cardiovascular Disease.

    PubMed

    Chirumbolo, Salvatore

    2016-07-01

    Dear Editor, The recent article by Mohammadzadeh et al.[1] on the latest issue of this Journal showed that the T allele +276G/T SNP of ADIPOQ gene is more associated with the increasing risk of coronary artery disease (CAD) in subjects with type 2 diabetes. Adipocytes were described in myocardial tissue of CAD patients and their role recently discussed[2,3]. Susceptibility to CAD by polymorphism in the Q gene of adiponectin has been reported for 3'-UTR, which harbours some genetic loci associated with metabolic risks and atherosclerosis[4]. Actually, previous studies have shown that the haplotype SNP +276G>T was associated with a decreased risk of CAD, after adjustment for potential confounding factors, therefore some controversial opinion still exists[5]. This evidence should be associated with the role exerted by adipocytes and adiponectin in heart physiology. In particular, in hypertensive disorder complicating pregnancy (HDCP), by investigating the population frequency of alleles, genotypes, and haplotypes of two single nucleotide polymorphisms (SNPs), namely +45T>G (rs2241766) and +276G>T (rs1501299), some authors found that the SNP +276 TT genotype was significantly associated with protection against HDCP, when compared to the pooled G genotypes[6]. Moreover, the same +276G/T SNP haplotype was strongly associated with biliary atresia, an intractable neonatal inflammatory and obliterative cholangiopathy, leading to progressive fibrosis and cirrhosis[7]. CAD is closely related to adiponectin biology. The same isoforms of adiponectin seem to be not associated to CAD severity but to glucose metabolism and its impairment[8]. In the paper by Mohammadzadeh et al.[1], T allele in +276G/T SNP haplotype is highly associated with CAD in subjects with type 2 diabetes, but this linkage should be reappraised if related much more to diabetes rather than CAD. Association of T allele in the indicated SNP with CAD may be an indirect consequence of type 2 diabetes, as reported

  17. Detecting local haplotype sharing and haplotype association

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel haplotype association method is presented, and its power is demonstrated. Relying on a statistical model for linkage disequilibrium (LD), the method first infers ancestral haplotypes and their loadings at each marker for each individual. The loadings are then used to quantify local haplotype...

  18. Genome-Wide Pharmacogenomic Study on Methadone Maintenance Treatment Identifies SNP rs17180299 and Multiple Haplotypes on CYP2B6, SPON1, and GSG1L Associated with Plasma Concentrations of Methadone R- and S-enantiomers in Heroin-Dependent Patients

    PubMed Central

    Yang, Hsin-Chou; Chu, Shih-Kai; Huang, Chieh-Liang; Kuo, Hsiang-Wei; Wang, Sheng-Chang; Liu, Sheng-Wen; Ho, Ing-Kang; Liu, Yu-Li

    2016-01-01

    Methadone maintenance treatment (MMT) is commonly used for controlling opioid dependence, preventing withdrawal symptoms, and improving the quality of life of heroin-dependent patients. A steady-state plasma concentration of methadone enantiomers, a measure of methadone metabolism, is an index of treatment response and efficacy of MMT. Although the methadone metabolism pathway has been partially revealed, no genome-wide pharmacogenomic study has been performed to identify genetic determinants and characterize genetic mechanisms for the plasma concentrations of methadone R- and S-enantiomers. This study was the first genome-wide pharmacogenomic study to identify genes associated with the plasma concentrations of methadone R- and S-enantiomers and their respective metabolites in a methadone maintenance cohort. After data quality control was ensured, a dataset of 344 heroin-dependent patients in the Han Chinese population of Taiwan who underwent MMT was analyzed. Genome-wide single-locus and haplotype-based association tests were performed to analyze four quantitative traits: the plasma concentrations of methadone R- and S-enantiomers and their respective metabolites. A significant single nucleotide polymorphism (SNP), rs17180299 (raw p = 2.24 × 10−8), was identified, accounting for 9.541% of the variation in the plasma concentration of the methadone R-enantiomer. In addition, 17 haplotypes were identified on SPON1, GSG1L, and CYP450 genes associated with the plasma concentration of methadone S-enantiomer. These haplotypes accounted for approximately one-fourth of the variation of the overall S-methadone plasma concentration. The association between the S-methadone plasma concentration and CYP2B6, SPON1, and GSG1L were replicated in another independent study. A gene expression experiment revealed that CYP2B6, SPON1, and GSG1L can be activated concomitantly through a constitutive androstane receptor (CAR) activation pathway. In conclusion, this study revealed new

  19. Genome-Wide Pharmacogenomic Study on Methadone Maintenance Treatment Identifies SNP rs17180299 and Multiple Haplotypes on CYP2B6, SPON1, and GSG1L Associated with Plasma Concentrations of Methadone R- and S-enantiomers in Heroin-Dependent Patients.

    PubMed

    Yang, Hsin-Chou; Chu, Shih-Kai; Huang, Chieh-Liang; Kuo, Hsiang-Wei; Wang, Sheng-Chang; Liu, Sheng-Wen; Ho, Ing-Kang; Liu, Yu-Li

    2016-03-01

    Methadone maintenance treatment (MMT) is commonly used for controlling opioid dependence, preventing withdrawal symptoms, and improving the quality of life of heroin-dependent patients. A steady-state plasma concentration of methadone enantiomers, a measure of methadone metabolism, is an index of treatment response and efficacy of MMT. Although the methadone metabolism pathway has been partially revealed, no genome-wide pharmacogenomic study has been performed to identify genetic determinants and characterize genetic mechanisms for the plasma concentrations of methadone R- and S-enantiomers. This study was the first genome-wide pharmacogenomic study to identify genes associated with the plasma concentrations of methadone R- and S-enantiomers and their respective metabolites in a methadone maintenance cohort. After data quality control was ensured, a dataset of 344 heroin-dependent patients in the Han Chinese population of Taiwan who underwent MMT was analyzed. Genome-wide single-locus and haplotype-based association tests were performed to analyze four quantitative traits: the plasma concentrations of methadone R- and S-enantiomers and their respective metabolites. A significant single nucleotide polymorphism (SNP), rs17180299 (raw p = 2.24 × 10(-8)), was identified, accounting for 9.541% of the variation in the plasma concentration of the methadone R-enantiomer. In addition, 17 haplotypes were identified on SPON1, GSG1L, and CYP450 genes associated with the plasma concentration of methadone S-enantiomer. These haplotypes accounted for approximately one-fourth of the variation of the overall S-methadone plasma concentration. The association between the S-methadone plasma concentration and CYP2B6, SPON1, and GSG1L were replicated in another independent study. A gene expression experiment revealed that CYP2B6, SPON1, and GSG1L can be activated concomitantly through a constitutive androstane receptor (CAR) activation pathway. In conclusion, this study revealed new

  20. Increased Frequency of De Novo Copy Number Variations in Congenital Heart Disease by Integrative Analysis of SNP Array and Exome Sequence Data

    PubMed Central

    Rodriguez-Murillo, Laura; Fromer, Menachem; Mazaika, Erica; Vardarajan, Badri; Italia, Michael; Leipzig, Jeremy; DePalma, Steven R.; Golhar, Ryan; Sanders, Stephan J.; Yamrom, Boris; Ronemus, Michael; Iossifov, Ivan; Willsey, A. Jeremy; State, Matthew W.; Kaltman, Jonathan R.; White, Peter S.; Shen, Yufeng; Warburton, Dorothy; Brueckner, Martina; Seidman, Christine; Goldmuntz, Elizabeth; Gelb, Bruce D.; Lifton, Richard; Seidman, Jonathan; Hakonarson, Hakon; Chung, Wendy K.

    2014-01-01

    Rationale Congenital heart disease (CHD) is among the most common birth defects. Most cases are of unknown etiology. Objective To determine the contribution of de novo copy number variants (CNVs) in the etiology of sporadic CHD. Methods and Results We studied 538 CHD trios using genome-wide dense single nucleotide polymorphism (SNP) arrays and/or whole exome sequencing (WES). Results were experimentally validated using digital droplet PCR. We compared validated CNVs in CHD cases to CNVs in 1,301 healthy control trios. The two complementary high-resolution technologies identified 63 validated de novo CNVs in 51 CHD cases. A significant increase in CNV burden was observed when comparing CHD trios with healthy trios, using either SNP array (p=7x10−5, Odds Ratio (OR)=4.6) or WES data (p=6x10−4, OR=3.5) and remained after removing 16% of de novo CNV loci previously reported as pathogenic (p=0.02, OR=2.7). We observed recurrent de novo CNVs on 15q11.2 encompassing CYFIP1, NIPA1, and NIPA2 and single de novo CNVs encompassing DUSP1, JUN, JUP, MED15, MED9, PTPRE SREBF1, TOP2A, and ZEB2, genes that interact with established CHD proteins NKX2-5 and GATA4. Integrating de novo variants in WES and CNV data suggests that ETS1 is the pathogenic gene altered by 11q24.2-q25 deletions in Jacobsen syndrome and that CTBP2 is the pathogenic gene in 10q sub-telomeric deletions. Conclusions We demonstrate a significantly increased frequency of rare de novo CNVs in CHD patients compared with healthy controls and suggest several novel genetic loci for CHD. PMID:25205790

  1. Probabilistic Multilocus Haplotype Reconstruction in Outcrossing Tetraploids.

    PubMed

    Zheng, Chaozhi; Voorrips, Roeland E; Jansen, Johannes; Hackett, Christine A; Ho, Julie; Bink, Marco C A M

    2016-05-01

    For both plant (e.g., potato) and animal (e.g., salmon) species, unveiling the genetic architecture of complex traits is key to the genetic improvement of polyploids in agriculture. F1 progenies of a biparental cross are often used for quantitative trait loci (QTL) mapping in outcrossing polyploids, where haplotype reconstruction by identifying the parental origins of marker alleles is necessary. In this paper, we build a novel and integrated statistical framework for multilocus haplotype reconstruction in a full-sib tetraploid family from biallelic marker dosage data collected from single-nucleotide polymorphism (SNP) arrays or next-generation sequencing technology given a genetic linkage map. Compared to diploids, in tetraploids, additional complexity needs to be addressed, including double reduction and possible preferential pairing of chromosomes. We divide haplotype reconstruction into two stages: parental linkage phasing for reconstructing the most probable parental haplotypes and ancestral inference for probabilistically reconstructing the offspring haplotypes conditional on the reconstructed parental haplotypes. The simulation studies and the application to real data from potato show that the parental linkage phasing is robust to, and that the subsequent ancestral inference is accurate for, complex chromosome pairing behaviors during meiosis, various marker segregation types, erroneous genetic maps except for long-range disturbances of marker ordering, various amounts of offspring dosage errors (up to ∼20%), and various fractions of missing data in parents and offspring dosages. PMID:26920758

  2. Subtyping of phosphoglucomutase locus 1 (PGM1) polymorphism in some populations of Rwanda: description of variant phenotypes, "haplotype" frequencies, and linkage disequilibrium data.

    PubMed

    Santachiara-Benerecetti, A S; Ranzani, G N; Antonini, G; Beretta, M

    1982-03-01

    Some populations of Rwanda (South Twa Pygmies, Hutu, and Tutsi) have been analyzed by acid starch gel electrophoresis for the subtyping of PGM1 polymorphism. The new polymorphic third PGM11 allele, the PGM1(1Twa), which we recently detected in Twa Pygmies from North Rwanda, has not been found in this survey, whereas the rare PGM1(6) allele attains subpolymorphic frequencies in all groups. Comparison between the various populations of Rwanda shows that they differ significantly from each other with the exception of South Twa Pygmies and Tutsi. A relatively low frequency (9.6%) of the PGM1(2S) allele appears to be typical of North Twa Pygmies; a low frequency of PGM1(2F) (1.2%-3.6%) has been found in all these groups but not in the Hutu (6.4%); and a particularly high incidence of the PGM1(1F) allele (the highest so far reported) has been observed in the South Twa Pygmies (20%) and in the Tutsi (18%). The PGM1(1Twa) and PGM1(6) enzymes, which in acid starch gel are not distinguishable, can be clearly differentiated by isoelectric focusing. In addition, the same technique has shown that the rare PGM1(7) allele observed in one Hutu is different from that found at polymorphic frequency in the Japanese and from a rare PGM1(7) allele found in Germany. On the very likely hypothesis that the PGM1(1S), PGM1(1F), PGM1(2S), and PGM1(2F) result from variations at two different polymorphic sites, 1/2 and F/S, within the PGM1 structural gene, all the available population data have been analyzed to investigate whether preferential combinations (haplotypes) were identifiable. Whereas Caucasians show a prevalence of 2F and 1S combination with an 8.02% mean value of linkage disequilibrium expressed as % Dmax, from the very few and scattered African data, it is impossible to draw any inference at present. PMID:6462057

  3. BM-SNP: A Bayesian Model for SNP Calling Using High Throughput Sequencing Data.

    PubMed

    Xu, Yanxun; Zheng, Xiaofeng; Yuan, Yuan; Estecio, Marcos R; Issa, Jean-Pierre; Qiu, Peng; Ji, Yuan; Liang, Shoudan

    2014-01-01

    A single-nucleotide polymorphism (SNP) is a sole base change in the DNA sequence and is the most common polymorphism. Detection and annotation of SNPs are among the central topics in biomedical research as SNPs are believed to play important roles on the manifestation of phenotypic events, such as disease susceptibility. To take full advantage of the next-generation sequencing (NGS) technology, we propose a Bayesian approach, BM-SNP, to identify SNPs based on the posterior inference using NGS data. In particular, BM-SNP computes the posterior probability of nucleotide variation at each covered genomic position using the contents and frequency of the mapped short reads. The position with a high posterior probability of nucleotide variation is flagged as a potential SNP. We apply BM-SNP to two cell-line NGS data, and the results show a high ratio of overlap ( >95 percent) with the dbSNP database. Compared with MAQ, BM-SNP identifies more SNPs that are in dbSNP, with higher quality. The SNPs that are called only by BM-SNP but not in dbSNP may serve as new discoveries. The proposed BM-SNP method integrates information from multiple aspects of NGS data, and therefore achieves high detection power. BM-SNP is fast, capable of processing whole genome data at 20-fold average coverage in a short amount of time. PMID:26357041

  4. MADD-FOLH1 Polymorphisms and Their Haplotypes with Serum Lipid Levels and the Risk of Coronary Heart Disease and Ischemic Stroke in a Chinese Han Population

    PubMed Central

    Wu, Dong-Feng; Yin, Rui-Xing; Cao, Xiao-Li; Huang, Feng; Wu, Jin-Zhen; Chen, Wu-Xian

    2016-01-01

    This study aimed to detect the association of the MADD-FOLH1 single nucleotide polymorphisms (SNPs) and their haplotypes with the risk of coronary heart disease (CHD) and ischemic stroke (IS) in a Chinese Han population. Six SNPs of rs7395662, rs326214, rs326217, rs1051006, rs3736101, and rs7120118 were genotyped in 584 CHD and 555 IS patients, and 596 healthy controls. The genotypic and allelic frequencies of the rs7395662 SNP were different between controls and patients, and the genotypes of the rs7395662 SNP were associated with the risk of CHD and IS in different genetic models. Six main haplotypes among the rs1051006, rs326214, rs326217, rs3736101, and rs7120118 SNPs were detected in our study population, the haplotypes of G-G-T-G-C and G-A-T-G-T were associated with an increased risk of CHD and IS, respectively. The subjects with rs7395662GG genotype in controls had higher triglyceride (TG) and lower high-density lipoprotein cholesterol (HDL-C) levels than the subjects with AA/AG genotypes. Several SNPs interacted with alcohol consumption to influence serum TG (rs326214, rs326217, and rs7120118) and HDL-C (rs7395662) levels. The SNP of rs3736101 interacted with cigarette smoking to modify serum HDL-C levels. The SNP of rs1051006 interacted with body mass index ≥24 kg/m2 to modulate serum low-density lipoprotein cholesterol levels. The interactions of several haplotypes and alcohol consumption on the risk of CHD and IS were also observed. PMID:27070640

  5. MADD-FOLH1 Polymorphisms and Their Haplotypes with Serum Lipid Levels and the Risk of Coronary Heart Disease and Ischemic Stroke in a Chinese Han Population.

    PubMed

    Wu, Dong-Feng; Yin, Rui-Xing; Cao, Xiao-Li; Huang, Feng; Wu, Jin-Zhen; Chen, Wu-Xian

    2016-01-01

    This study aimed to detect the association of the MADD-FOLH1 single nucleotide polymorphisms (SNPs) and their haplotypes with the risk of coronary heart disease (CHD) and ischemic stroke (IS) in a Chinese Han population. Six SNPs of rs7395662, rs326214, rs326217, rs1051006, rs3736101, and rs7120118 were genotyped in 584 CHD and 555 IS patients, and 596 healthy controls. The genotypic and allelic frequencies of the rs7395662 SNP were different between controls and patients, and the genotypes of the rs7395662 SNP were associated with the risk of CHD and IS in different genetic models. Six main haplotypes among the rs1051006, rs326214, rs326217, rs3736101, and rs7120118 SNPs were detected in our study population, the haplotypes of G-G-T-G-C and G-A-T-G-T were associated with an increased risk of CHD and IS, respectively. The subjects with rs7395662GG genotype in controls had higher triglyceride (TG) and lower high-density lipoprotein cholesterol (HDL-C) levels than the subjects with AA/AG genotypes. Several SNPs interacted with alcohol consumption to influence serum TG (rs326214, rs326217, and rs7120118) and HDL-C (rs7395662) levels. The SNP of rs3736101 interacted with cigarette smoking to modify serum HDL-C levels. The SNP of rs1051006 interacted with body mass index ≥24 kg/m² to modulate serum low-density lipoprotein cholesterol levels. The interactions of several haplotypes and alcohol consumption on the risk of CHD and IS were also observed. PMID:27070640

  6. Use of Haplotypes to Estimate Mendelian Sampling Effects and Selection Limits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limits to selection and Mendelian sampling terms can be calculated using haplotypes, by summing the individual additive effects on each chromosome. Haplotypes were imputed for 43,382 single nucleotide polymorphisms (SNP) in 1,455 Brown Swiss, 40,351 Holstein, and 4,064 Jersey bulls and cows using th...

  7. Genome-wide association of familial prostate cancer cases identifies evidence for a rare segregating haplotype at 8q24.21.

    PubMed

    Teerlink, Craig C; Leongamornlert, Daniel; Dadaev, Tokhir; Thomas, Alun; Farnham, James; Stephenson, Robert A; Riska, Shaun; McDonnell, Shannon K; Schaid, Daniel J; Catalona, William J; Zheng, S Lilly; Cooney, Kathleen A; Ray, Anna M; Zuhlke, Kimberly A; Lange, Ethan M; Giles, Graham G; Southey, Melissa C; Fitzgerald, Liesel M; Rinckleb, Antje; Luedeke, Manuel; Maier, Christiane; Stanford, Janet L; Ostrander, Elaine A; Kaikkonen, Elina M; Sipeky, Csilla; Tammela, Teuvo; Schleutker, Johanna; Wiley, Kathleen E; Isaacs, Sarah D; Walsh, Patrick C; Isaacs, William B; Xu, Jianfeng; Cancel-Tassin, Geraldine; Cussenot, Olivier; Mandal, Diptasri; Laurie, Cecelia; Laurie, Cathy; Thibodeau, Stephen N; Eeles, Rosalind A; Kote-Jarai, Zsofia; Cannon-Albright, Lisa

    2016-08-01

    Previous genome-wide association studies (GWAS) of prostate cancer risk focused on cases unselected for family history and have reported over 100 significant associations. The International Consortium for Prostate Cancer Genetics (ICPCG) has now performed a GWAS of 2511 (unrelated) familial prostate cancer cases and 1382 unaffected controls from 12 member sites. All samples were genotyped on the Illumina 5M+exome single nucleotide polymorphism (SNP) platform. The GWAS identified a significant evidence for association for SNPs in six regions previously associated with prostate cancer in population-based cohorts, including 3q26.2, 6q25.3, 8q24.21, 10q11.23, 11q13.3, and 17q12. Of note, SNP rs138042437 (p = 1.7e(-8)) at 8q24.21 achieved a large estimated effect size in this cohort (odds ratio = 13.3). 116 previously sampled affected relatives of 62 risk-allele carriers from the GWAS cohort were genotyped for this SNP, identifying 78 additional affected carriers in 62 pedigrees. A test for an excess number of affected carriers among relatives exhibited strong evidence for co-segregation of the variant with disease (p = 8.5e(-11)). The majority (92 %) of risk-allele carriers at rs138042437 had a consistent estimated haplotype spanning approximately 100 kb of 8q24.21 that contained the minor alleles of three rare SNPs (dosage minor allele frequencies <1.7 %), rs183373024 (PRNCR1), previously associated SNP rs188140481, and rs138042437 (CASC19). Strong evidence for co-segregation of a SNP on the haplotype further characterizes the haplotype as a prostate cancer predisposition locus. PMID:27262462

  8. No association between polymorphisms/haplotypes of the vascular endothelial growth factor gene and preeclampsia

    PubMed Central

    2011-01-01

    Background Preeclampsia (PE) is the first worldwide cause of death in pregnant women, intra-uterine growth retardation, and fetal prematurity. Some vascular endothelial grown factor gene (VEGF) polymorphisms have been associated to PE and other pregnancy disturbances. We evaluated the associations between VEGF genotypes/haplotypes and PE in Mexican women. Methods 164 pregnant women were enrolled in a case-control study (78 cases and 86 normotensive pregnant controls). The rs699947 (-2578C/A), rs1570360 (-1154G/A), rs2010963 (+405G/C), and rs25648 (-7C/T), VEGF variants were discriminated using Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) methods or Taqman single nucleotide polymorphism (SNP) assays. Results The proportions of the minor allele for rs699947, rs1570360, rs2010963, and rs25648 VEGF SNPs were 0.33, 0.2, 0.39, and 0.17 in controls, and 0.39, 0.23, 0.41, and 0.15 in cases, respectively (P values > 0.05). The most frequent haplotypes of rs699947, rs1570360, rs2010963, and rs25648 VEGF SNPs, were C-G-C-C and C-G-G-C with frequencies of 0.39, 0.21 in cases and 0.37, 0.25 in controls, respectively (P values > 0.05) Conclusion There was no evidence of an association between VEGF alleles, genotypes, or haplotypes frequencies and PE in our study. PMID:21575227

  9. Haplotypes of the D-Amino Acid Oxidase Gene Are Significantly Associated with Schizophrenia and Its Neurocognitive Deficits

    PubMed Central

    Hwu, Hai-Gwo; Fann, Cathy Shen-Jang; Yang, Ueng-Cheng; Yang, Wei-Chih; Hsu, Pei-Chun; Chang, Chien-Ching; Wen, Chun-Chiang; Tsai-Wu, Jyy-Jih; Hwang, Tzung-Jeng; Hsieh, Ming H.; Liu, Chen-Chung; Chien, Yi-Ling; Fang, Chiu-Ping; Faraone, Stephen V.; Tsuang, Ming T.; Chen, Wei J.; Liu, Chih-Min

    2016-01-01

    D-amino acid oxidase (DAO) has been reported to be associated with schizophrenia. This study aimed to search for genetic variants associated with this gene. The genomic regions of all exons, highly conserved regions of introns, and promoters of this gene were sequenced. Potentially meaningful single-nucleotide polymorphisms (SNPs) obtained from direct sequencing were selected for genotyping in 600 controls and 912 patients with schizophrenia and in a replicated sample consisting of 388 patients with schizophrenia. Genetic associations were examined using single-locus and haplotype association analyses. In single-locus analyses, the frequency of the C allele of a novel SNP rs55944529 located at intron 8 was found to be significantly higher in the original large patient sample (p = 0.016). This allele was associated with a higher level of DAO mRNA expression in the Epstein-Barr virus-transformed lymphocytes. The haplotype distribution of a haplotype block composed of rs11114083-rs2070586-rs2070587-rs55944529 across intron 1 and intron 8 was significantly different between the patients and controls and the haplotype frequencies of AAGC were significantly higher in patients, in both the original (corrected p < 0.0001) and replicated samples (corrected p = 0.0003). The CGTC haplotype was specifically associated with the subgroup with deficits in sustained attention and executive function and the AAGC haplotype was associated with the subgroup without such deficits. The DAO gene was a susceptibility gene for schizophrenia and the genomic region between intron 1 and intron 8 may harbor functional genetic variants, which may influence the mRNA expression of DAO and neurocognitive functions in schizophrenia. PMID:26986737

  10. High Frequency of Haplotype HLA-DQ7 in Celiac Disease Patients from South Italy: Retrospective Evaluation of 5,535 Subjects at Risk of Celiac Disease

    PubMed Central

    Tinto, Nadia; Cola, Arturo; Piscopo, Chiara; Capuano, Marina; Galatola, Martina; Greco, Luigi; Sacchetti, Lucia

    2015-01-01

    Background Celiac disease (CD) has a strong genetic component mainly due to HLA DQ2/DQ8 encoding genes. However, a minority of CD patients are DQ2/DQ8-negative. To address this issue, we retrospectively characterized HLA haplotypes in 5,535 subjects at risk of CD (either relatives of CD patients or subjects with CD-like symptoms) referred to our center during a 10-year period. Methods We identified loci DQA1/DQB1/DRB1 by sequence-specific oligonucleotide-PCR and sequence-specific primer-PCR; anti-transglutaminase IgA/IgG and anti-endomysium IgA by ELISA and indirect immunofluorescence, respectively. Results We diagnosed CD in 666/5,535 individuals, 4.2% of whom were DQ2/DQ8-negative. Interestingly, DQ7 was one of the most abundant haplotypes in all CD patients and significantly more frequent in DQ2/DQ8-negative (38%) than in DQ2/DQ8-positive CD patients (24%) (p<0.05). Conclusion Our data lend support to the concept that DQ7 represents an additive or independent CD risk haplotype with respect to DQ2/DQ8 haplotypes but this finding should be verified in other large CD populations. PMID:26398634

  11. Haplotype kernel association test as a powerful method to identify chromosomal regions harboring uncommon causal variants.

    PubMed

    Lin, Wan-Yu; Yi, Nengjun; Lou, Xiang-Yang; Zhi, Degui; Zhang, Kui; Gao, Guimin; Tiwari, Hemant K; Liu, Nianjun

    2013-09-01

    For most complex diseases, the fraction of heritability that can be explained by the variants discovered from genome-wide association studies is minor. Although the so-called "rare variants" (minor allele frequency [MAF] < 1%) have attracted increasing attention, they are unlikely to account for much of the "missing heritability" because very few people may carry these rare variants. The genetic variants that are likely to fill in the "missing heritability" include uncommon causal variants (MAF < 5%), which are generally untyped in association studies using tagging single-nucleotide polymorphisms (SNPs) or commercial SNP arrays. Developing powerful statistical methods can help to identify chromosomal regions harboring uncommon causal variants, while bypassing the genome-wide or exome-wide next-generation sequencing. In this work, we propose a haplotype kernel association test (HKAT) that is equivalent to testing the variance component of random effects for distinct haplotypes. With an appropriate weighting scheme given to haplotypes, we can further enhance the ability of HKAT to detect uncommon causal variants. With scenarios simulated according to the population genetics theory, HKAT is shown to be a powerful method for detecting chromosomal regions harboring uncommon causal variants. PMID:23740760

  12. Haplotype Kernel Association Test as a Powerful Method to Identify Chromosomal Regions Harboring Uncommon Causal Variants

    PubMed Central

    Lin, Wan-Yu; Yi, Nengjun; Lou, Xiang-Yang; Zhi, Degui; Zhang, Kui; Gao, Guimin; Tiwari, Hemant K.; Liu, Nianjun

    2014-01-01

    For most complex diseases, the fraction of heritability that can be explained by the variants discovered from genome-wide association studies is minor. Although the so-called ‘rare variants’ (minor allele frequency [MAF] < 1%) have attracted increasing attention, they are unlikely to account for much of the ‘missing heritability’ because very few people may carry these rare variants. The genetic variants that are likely to fill in the ‘missing heritability’ include uncommon causal variants (MAF < 5%), which are generally untyped in association studies using tagging single-nucleotide polymorphisms (SNPs) or commercial SNP arrays. Developing powerful statistical methods can help to identify chromosomal regions harboring uncommon causal variants, while bypassing the genome-wide or exome-wide next-generation sequencing. In this work, we propose a haplotype kernel association test (HKAT) that is equivalent to testing the variance component of random effects for distinct haplotypes. With an appropriate weighting scheme given to haplotypes, we can further enhance the ability of HKAT to detect uncommon causal variants. With scenarios simulated according to the population genetics theory, HKAT is shown to be a powerful method for detecting chromosomal regions harboring uncommon causal variants. PMID:23740760

  13. SNP Haplotypes: Unveiling the Truth of Past Relationships

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the last ten years, molecular markers have been widely accepted as a breeding tool for crop improvement. Currently, microsatellite markers are being used in rice to select for several simply inherited traits like components of cooking quality and a number of major genes linked to resistance to ...

  14. The SNP Consortium website: past, present and future.

    PubMed

    Thorisson, Gudmundur A; Stein, Lincoln D

    2003-01-01

    The SNP Consortium website (http://snp.cshl.org) has undergone many changes since its initial conception three years ago. The database back end has been changed from the venerable ACeDB to the more scalable MySQL engine. Users can access the data via gene or single nucleotide polymorphism (SNP) keyword searches and browse or dump SNP data to textfiles. A graphical genome browsing interface shows SNPs mapped onto the genome assembly in the context of externally available gene predictions and other features. SNP allele frequency and genotype data are available via FTP-download and on individual SNP report web pages. SNP linkage maps are available for download and for browsing in a comparative map viewer. All software components of the data coordinating center (DCC) website (http://snp.cshl.org) are open source. PMID:12519964

  15. Mapping MHC haplotype effects in unrelated donor hematopoietic cell transplantation

    PubMed Central

    Malkki, Mari; Horowitz, Mary M.; Spellman, Stephen R.; Haagenson, Michael D.; Wang, Tao

    2013-01-01

    Life-threatening risks associated with HLA-mismatched unrelated donor hematopoietic cell transplantation limit its general application for the treatment of blood diseases. The increased risks might be explained by undetected genetic variation within the highly polymorphic major histocompatibility complex (MHC) region. We retrospectively assessed each of 1108 MHC region single nucleotide polymorphisms (SNPs) in 2628 patients and their HLA-mismatched unrelated donors to determine whether SNPs are associated with the risk of mortality, disease-free survival, transplant-related mortality, relapse, and acute and chronic graft-versus-host disease (GVHD). Multivariate analysis adjusted for HLA mismatching and nongenetic variables associated with each clinical end point. Twelve SNPs were identified as transplantation determinants. SNP-associated risks were conferred by either patient or donor SNP genotype or by patient-donor SNP mismatching. Risks after transplantation increased with increasing numbers of unfavorable SNPs. SNPs that influenced acute GVHD were independent of those that affected risk of chronic GVHD and relapse. HLA haplotypes differed with respect to haplotype content of (un)favorable SNPs. Outcome after HLA-mismatched unrelated donor transplantation is influenced by MHC region variation that is undetected with conventional HLA typing. Knowledge of the SNP content of HLA haplotypes provides a means to estimate risks prior to transplantation and to lower complications through judicious selection of donors with favorable MHC genetics. PMID:23305741

  16. Imputation of microsatellite alleles from dense SNP genotypes for parentage verification across multiple Bos taurus and Bos indicus breeds

    PubMed Central

    McClure, Matthew C.; Sonstegard, Tad S.; Wiggans, George R.; Van Eenennaam, Alison L.; Weber, Kristina L.; Penedo, Cecilia T.; Berry, Donagh P.; Flynn, John; Garcia, Jose F.; Carmo, Adriana S.; Regitano, Luciana C. A.; Albuquerque, Milla; Silva, Marcos V. G. B.; Machado, Marco A.; Coffey, Mike; Moore, Kirsty; Boscher, Marie-Yvonne; Genestout, Lucie; Mazza, Raffaele; Taylor, Jeremy F.; Schnabel, Robert D.; Simpson, Barry; Marques, Elisa; McEwan, John C.; Cromie, Andrew; Coutinho, Luiz L.; Kuehn, Larry A.; Keele, John W.; Piper, Emily K.; Cook, Jim; Williams, Robert; Van Tassell, Curtis P.

    2013-01-01

    To assist cattle producers transition from microsatellite (MS) to single nucleotide polymorphism (SNP) genotyping for parental verification we previously devised an effective and inexpensive method to impute MS alleles from SNP haplotypes. While the reported method was verified with only a limited data set (N = 479) from Brown Swiss, Guernsey, Holstein, and Jersey cattle, some of the MS-SNP haplotype associations were concordant across these phylogenetically diverse breeds. This implied that some haplotypes predate modern breed formation and remain in strong linkage disequilibrium. To expand the utility of MS allele imputation across breeds, MS and SNP data from more than 8000 animals representing 39 breeds (Bos taurus and B. indicus) were used to predict 9410 SNP haplotypes, incorporating an average of 73 SNPs per haplotype, for which alleles from 12 MS markers could be accurately be imputed. Approximately 25% of the MS-SNP haplotypes were present in multiple breeds (N = 2 to 36 breeds). These shared haplotypes allowed for MS imputation in breeds that were not represented in the reference population with only a small increase in Mendelian inheritance inconsistancies. Our reported reference haplotypes can be used for any cattle breed and the reported methods can be applied to any species to aid the transition from MS to SNP genetic markers. While ~91% of the animals with imputed alleles for 12 MS markers had ≤1 Mendelian inheritance conflicts with their parents' reported MS genotypes, this figure was 96% for our reference animals, indicating potential errors in the reported MS genotypes. The workflow we suggest autocorrects for genotyping errors and rare haplotypes, by MS genotyping animals whose imputed MS alleles fail parentage verification, and then incorporating those animals into the reference dataset. PMID:24065982

  17. Genome patterns of selection and introgression of haplotypes in natural populations of the house mouse (Mus musculus).

    PubMed

    Staubach, Fabian; Lorenc, Anna; Messer, Philipp W; Tang, Kun; Petrov, Dmitri A; Tautz, Diethard

    2012-01-01

    General parameters of selection, such as the frequency and strength of positive selection in natural populations or the role of introgression, are still insufficiently understood. The house mouse (Mus musculus) is a particularly well-suited model system to approach such questions, since it has a defined history of splits into subspecies and populations and since extensive genome information is available. We have used high-density single-nucleotide polymorphism (SNP) typing arrays to assess genomic patterns of positive selection and introgression of alleles in two natural populations of each of the subspecies M. m. domesticus and M. m. musculus. Applying different statistical procedures, we find a large number of regions subject to apparent selective sweeps, indicating frequent positive selection on rare alleles or novel mutations. Genes in the regions include well-studied imprinted loci (e.g. Plagl1/Zac1), homologues of human genes involved in adaptations (e.g. alpha-amylase genes) or in genetic diseases (e.g. Huntingtin and Parkin). Haplotype matching between the two subspecies reveals a large number of haplotypes that show patterns of introgression from specific populations of the respective other subspecies, with at least 10% of the genome being affected by partial or full introgression. Using neutral simulations for comparison, we find that the size and the fraction of introgressed haplotypes are not compatible with a pure migration or incomplete lineage sorting model. Hence, it appears that introgressed haplotypes can rise in frequency due to positive selection and thus can contribute to the adaptive genomic landscape of natural populations. Our data support the notion that natural genomes are subject to complex adaptive processes, including the introgression of haplotypes from other differentiated populations or species at a larger scale than previously assumed for animals. This implies that some of the admixture found in inbred strains of mice may also have

  18. METU-SNP: an integrated software system for SNP-complex disease association analysis.

    PubMed

    Ustünkar, Gürkan; Aydın Son, Yeşim

    2011-01-01

    Recently, there has been increasing research to discover genomic biomarkers, haplotypes, and potentially other variables that together contribute to the development of diseases. Single Nucleotide Polymorphisms (SNPs) are the most common form of genomic variations and they can represent an individual’s genetic variability in greatest detail. Genome-wide association studies (GWAS) of SNPs, high-dimensional case-control studies, are among the most promising approaches for identifying disease causing variants. METU-SNP software is a Java based integrated desktop application specifically designed for the prioritization of SNP biomarkers and the discovery of genes and pathways related to diseases via analysis of the GWAS case-control data. Outputs of METU-SNP can easily be utilized for the downstream biomarkers research to allow the prediction and the diagnosis of diseases and other personalized medical approaches. Here, we introduce and describe the system functionality and architecture of the METU-SNP. We believe that the METU-SNP will help researchers with the reliable identification of SNPs that are involved in the etiology of complex diseases, ultimately supporting the development of personalized medicine approaches and targeted drug discoveries. PMID:22156365

  19. High diversity of alpha-globin haplotypes in a Senegalese population, including many previously unreported variants.

    PubMed Central

    Martinson, J J; Excoffier, L; Swinburn, C; Boyce, A J; Harding, R M; Langaney, A; Clegg, J B

    1995-01-01

    RFLP haplotypes at the alpha-globin gene complex have been examined in 190 individuals from the Niokolo Mandenka population of Senegal: haplotypes were assigned unambiguously for 210 chromosomes. The Mandenka share with other African populations a sample size-independent haplotype diversity that is much greater than that in any non-African population: the number of haplotypes observed in the Mandenka is typically twice that seen in the non-African populations sampled to date. Of these haplotypes, 17.3% had not been observed in any previous surveys, and a further 19.1% have previously been reported only in African populations. The haplotype distribution shows clear differences between African and non-African peoples, but this is on the basis of population-specific haplotypes combined with haplotypes common to all. The relationship of the newly reported haplotypes to those previously recorded suggests that several mutation processes, particularly recombination as homologous exchange or gene conversion, have been involved in their production. A computer program based on the expectation-maximization (EM) algorithm was used to obtain maximum-likelihood estimates of haplotype frequencies for the entire data set: good concordance between the unambiguous and EM-derived sets was seen for the overall haplotype frequencies. Some of the low-frequency haplotypes reported by the estimation algorithm differ greatly, in structure, from those haplotypes known to be present in human populations, and they may not represent haplotypes actually present in the sample. PMID:7485171

  20. Differential frequency of NKG2C/KLRC2 deletion in distinct African populations and susceptibility to Trachoma: a new method for imputation of KLRC2 genotypes from SNP genotyping data.

    PubMed

    Goncalves, Adriana; Makalo, Pateh; Joof, Hassan; Burr, Sarah; Ramadhani, Athumani; Massae, Patrick; Malisa, Aiweda; Mtuy, Tara; Derrick, Tamsyn; Last, Anna R; Nabicassa, Meno; Cassama, Eunice; Houghton, Joanna; Palmer, Christine D; Pickering, Harry; Burton, Matthew J; Mabey, David C W; Bailey, Robin L; Goodier, Martin R; Holland, Martin J; Roberts, Chrissy H

    2016-08-01

    NKG2C is an activating receptor that is preferentially expressed on natural killer (NK) cells. The gene encoding NKG2C (killer cell lectin-like receptor C2, KLRC2) is present at different copy numbers in the genomes of different individuals. Deletion at the NKG2C locus was investigated in a case-control study of 1522 individuals indigenous to East- and West-Africa and the association with the ocular Chlamydia trachomatis infection and its sequelae was explored. The frequency of homozygous KLRC2 deletion was 13.7 % in Gambians and 4.7 % in Tanzanians. A significantly higher frequency of the deletion allele was found in West-Africans from the Gambia and Guinea-Bissau (36.2 % p = 2.105 × 10(-8), 26.8 % p = 0.050; respectively) in comparison to East-African Tanzanians where the frequency of the deletion is comparable to other human populations (20.9 %). We found no evidence for an association between the numbers of KLRC2 gene copies and the clinical manifestations of trachoma (follicular trachoma or conjunctival scarring). A new method for imputation of KLRC2 genotypes from single nucleotide polymorphism (SNP) data in 2621 individuals from the Gambia further confirmed these results. Our data suggest that NKG2C does not play a major role in trachomatous disease. We found that the deletion allele is present at different frequencies in different populations but the reason behind these differences is currently not understood. The new method offers the potential to use SNP arrays from genome wide association studies to study the frequency of KLRC2 deletion in other populations and its association with other diseases. PMID:27312142

  1. Haplotyping the human leukocyte antigen system from single chromosomes

    PubMed Central

    Murphy, Nicholas M.; Burton, Matthew; Powell, David R.; Rossello, Fernando J.; Cooper, Don; Chopra, Abha; Hsieh, Ming Je; Sayer, David C.; Gordon, Lavinia; Pertile, Mark D; Tait, Brian D.; Irving, Helen R.; Pouton, Colin W.

    2016-01-01

    We describe a method for determining the parental HLA haplotypes of a single individual without recourse to conventional segregation genetics. Blood samples were cultured to identify and sort chromosome 6 by bivariate flow cytometry. Single chromosome 6 amplification products were confirmed with a single nucleotide polymorphism (SNP) array and verified by deep sequencing to enable assignment of both alleles at the HLA loci, defining the two haplotypes. This study exemplifies a rapid and efficient method of haplotyping that can be applied to any chromosome pair, or indeed all chromosome pairs, using a single sorting operation. The method represents a cost-effective approach to complete phasing of SNPs, which will facilitate a deeper understanding of the links between SNPs, gene regulation and protein function. PMID:27461731

  2. Haplotyping the human leukocyte antigen system from single chromosomes.

    PubMed

    Murphy, Nicholas M; Burton, Matthew; Powell, David R; Rossello, Fernando J; Cooper, Don; Chopra, Abha; Hsieh, Ming Je; Sayer, David C; Gordon, Lavinia; Pertile, Mark D; Tait, Brian D; Irving, Helen R; Pouton, Colin W

    2016-01-01

    We describe a method for determining the parental HLA haplotypes of a single individual without recourse to conventional segregation genetics. Blood samples were cultured to identify and sort chromosome 6 by bivariate flow cytometry. Single chromosome 6 amplification products were confirmed with a single nucleotide polymorphism (SNP) array and verified by deep sequencing to enable assignment of both alleles at the HLA loci, defining the two haplotypes. This study exemplifies a rapid and efficient method of haplotyping that can be applied to any chromosome pair, or indeed all chromosome pairs, using a single sorting operation. The method represents a cost-effective approach to complete phasing of SNPs, which will facilitate a deeper understanding of the links between SNPs, gene regulation and protein function. PMID:27461731

  3. Fast Sampling-Based Whole-Genome Haplotype Block Recognition.

    PubMed

    Taliun, Daniel; Gamper, Johann; Leser, Ulf; Pattaro, Cristian

    2016-01-01

    Scaling linkage disequilibrium (LD) based haplotype block recognition to the entire human genome has always been a challenge. The best-known algorithm has quadratic runtime complexity and, even when sophisticated search space pruning is applied, still requires several days of computations. Here, we propose a novel sampling-based algorithm, called S-MIG (++), where the main idea is to estimate the area that most likely contains all haplotype blocks by sampling a very small number of SNP pairs. A subsequent refinement step computes the exact blocks by considering only the SNP pairs within the estimated area. This approach significantly reduces the number of computed LD statistics, making the recognition of haplotype blocks very fast. We theoretically and empirically prove that the area containing all haplotype blocks can be estimated with a very high degree of certainty. Through experiments on the 243,080 SNPs on chromosome 20 from the 1,000 Genomes Project, we compared our previous algorithm MIG (++) with the new S-MIG (++) and observed a runtime reduction from 2.8 weeks to 34.8 hours. In a parallelized version of the S-MIG (++) algorithm using 32 parallel processes, the runtime was further reduced to 5.1 hours. PMID:27045830

  4. Investigation of the functional role of human Interleukin-8 gene haplotypes by CRISPR/Cas9 mediated genome editing.

    PubMed

    Benakanakere, Manjunatha R; Finoti, Livia S; Tanaka, Urara; Grant, Gregory R; Scarel-Caminaga, Raquel M; Kinane, Denis F

    2016-01-01

    Interleukin-8 (IL-8) gene polymorphisms have been considered as susceptibility factors in periodontal disease. However, the functional roles of IL-8 gene haplotypes have not been investigated. Here, we demonstrate for the first time the use of the CRISPR/Cas9 system to engineer the IL-8 gene, and tested the functionality of different haplotypes. Two sgRNAs vectors targeting the IL-8 gene and the naked homologous repair DNA carrying different haplotypes were used to successfully generate HEK293T cells carrying the AT genotype at the first SNP - rs4073 (alias -251), TT genotype at the second SNP - rs2227307 (alias +396), TC or CC genotypes at the third SNP - rs2227306 (alias +781) at the IL-8 locus. When stimulated with Poly I:C, ATC/TTC haplotype, cells significantly up-regulated the IL-8 at both transcriptional and translational levels. To test whether ATC/TTC haplotype is functional, we used a trans-well assay to measure the transmigration of primary neutrophils incubated with supernatants from the Poly I:C stimulation experiment. ATC/TTC haplotype cells significantly increased transmigration of neutrophils confirming the functional role for this IL-8 haplotype. Taken together, our data provides evidence that carriage of the ATC/TTC haplotype in itself may increase the influx of neutrophils in inflammatory lesions and influence disease susceptibility. PMID:27499075

  5. Investigation of the functional role of human Interleukin-8 gene haplotypes by CRISPR/Cas9 mediated genome editing

    PubMed Central

    Benakanakere, Manjunatha R.; Finoti, Livia S.; Tanaka, Urara; Grant, Gregory R.; Scarel-Caminaga, Raquel M.; Kinane, Denis F.

    2016-01-01

    Interleukin-8 (IL-8) gene polymorphisms have been considered as susceptibility factors in periodontal disease. However, the functional roles of IL-8 gene haplotypes have not been investigated. Here, we demonstrate for the first time the use of the CRISPR/Cas9 system to engineer the IL-8 gene, and tested the functionality of different haplotypes. Two sgRNAs vectors targeting the IL-8 gene and the naked homologous repair DNA carrying different haplotypes were used to successfully generate HEK293T cells carrying the AT genotype at the first SNP - rs4073 (alias -251), TT genotype at the second SNP - rs2227307 (alias +396), TC or CC genotypes at the third SNP - rs2227306 (alias +781) at the IL-8 locus. When stimulated with Poly I:C, ATC/TTC haplotype, cells significantly up-regulated the IL-8 at both transcriptional and translational levels. To test whether ATC/TTC haplotype is functional, we used a trans-well assay to measure the transmigration of primary neutrophils incubated with supernatants from the Poly I:C stimulation experiment. ATC/TTC haplotype cells significantly increased transmigration of neutrophils confirming the functional role for this IL-8 haplotype. Taken together, our data provides evidence that carriage of the ATC/TTC haplotype in itself may increase the influx of neutrophils in inflammatory lesions and influence disease susceptibility. PMID:27499075

  6. Analysis of DNA polymorphisms in sugar beet (Beta vulgaris L.) and development of an SNP-based map of expressed genes.

    PubMed

    Schneider, Katharina; Kulosa, Dagmar; Soerensen, Thomas Rosleff; Möhring, Silke; Heine, Martin; Durstewitz, Gregor; Polley, Andreas; Weber, Eberhard; Jamsari; Lein, Jens; Hohmann, Uwe; Tahiro, Emma; Weisshaar, Bernd; Schulz, Britta; Koch, Georg; Jung, Christian; Ganal, Martin

    2007-09-01

    A panel of 13 sugar beet lines and one genotype each of the Beta vulgaris cultivars red beet and Swiss chard, and B. vulgaris ssp. maritima were used to identify polymorphisms in alignments of genomic DNA sequences derived from 315 EST- and 43 non-coding RFLP-derived loci. In sugar beet lines, loci of expressed genes showed an average SNP frequency of 1/72 bp, 1 in 58 bp in non-coding sequences, increasing to 1/47 bp upon the addition of the remaining genotypes. Within analysed DNA fragments, alleles at different SNP positions displayed linkage disequilibrium indicative of haplotype structures. On average 2.7 haplotypes were found in sugar beet lines, and haplotype conservation in expressed genes appeared to exceed 500 bp in length. Seven different genotyping techniques including SNP detection by MALDI-TOF mass spectrometry, pyrosequencing and fluorescence scanning of labelled nucleotides were employed to perform 712 segregation analyses for 538 markers in three F(2) populations. Functions were predicted for 492 mapped sequences. Genetic maps comprised 305 loci covering 599.8 cM in population K1, 241 loci distributed over 636.6 cM in population D2, and 166 loci over 507.1 cM in population K2, respectively. Based on 156 markers common to more than one population an integrated map was constructed with 524 loci covering 664.3 cM. For 377 loci the genome positions of the most similar sequences from A. thaliana were identified, but little evidence for previously presented ancestral genome structures was found. PMID:17622508

  7. Haplotype of single nucleotide polymorphisms in exon 6 of the MZF-1 gene and Alzheimer's disease.

    PubMed

    Porcellini, Elisa; Carbone, Ilaria; Martelli, Pier Luigi; Ianni, Manuela; Casadio, Rita; Pession, Annalisa; Licastro, Federico

    2013-01-01

    Our previous works showed that single nucleotide polymorphisms (SNPs) in genes with regulatory function upon inflammatory response and cholesterol metabolism were associated with Alzheimer's disease (AD) risk. The list comprises SNPs located on the promoters of alpha 1 antichymotrypsin (rs1884082), hydroxy methyl glutaryl coenzime A reductase (rs376140), tumor necrosis factor alpha (rs1800629), and interleukin 10 (rs1800869). Here we investigated the effect of these SNPs on the binding for transcription factors. We computationally detected putative binding sites for transcription factors located in the SNP regions. To this aim, the TESS program for scanning the promoter sequences against the binding-site models available at TRANSFACT and JASPAR databases was adopted. All the analyzed SNPs appeared to affect the binding of myeloid zinc finger protein 1 (MZF-1) to the promoter sequence of the above reported genes. Therefore 16 SNPs in MZF-1 gene were tested in 120 AD cases and 88 controls to asses a possible association between MZF-1 and AD. 14 SNPs showed no variability in AD and control populations, while two SNPs rs4756 and rs2228162 showed the three genotypes. Genotype distributions and allele frequencies of these two SNPs were comparable between AD and controls. On the other hand, the haplotype distribution of rs4756 and rs2228162 was different between AD and controls; being the AG haplotype associated with a decreased AD risk. In conclusion, selected SNPs in MZF-1 gene exert a minor effect on AD risk. PMID:23241556

  8. Construction of a versatile SNP array for pyramiding useful genes of rice.

    PubMed

    Kurokawa, Yusuke; Noda, Tomonori; Yamagata, Yoshiyuki; Angeles-Shim, Rosalyn; Sunohara, Hidehiko; Uehara, Kanako; Furuta, Tomoyuki; Nagai, Keisuke; Jena, Kshirod Kumar; Yasui, Hideshi; Yoshimura, Atsushi; Ashikari, Motoyuki; Doi, Kazuyuki

    2016-01-01

    DNA marker-assisted selection (MAS) has become an indispensable component of breeding. Single nucleotide polymorphisms (SNP) are the most frequent polymorphism in the rice genome. However, SNP markers are not readily employed in MAS because of limitations in genotyping platforms. Here the authors report a Golden Gate SNP array that targets specific genes controlling yield-related traits and biotic stress resistance in rice. As a first step, the SNP genotypes were surveyed in 31 parental varieties using the Affymetrix Rice 44K SNP microarray. The haplotype information for 16 target genes was then converted to the Golden Gate platform with 143-plex markers. Haplotypes for the 14 useful allele are unique and can discriminate among all other varieties. The genotyping consistency between the Affymetrix microarray and the Golden Gate array was 92.8%, and the accuracy of the Golden Gate array was confirmed in 3 F2 segregating populations. The concept of the haplotype-based selection by using the constructed SNP array was proofed. PMID:26566831

  9. Identification and genetic effect of haplotype in the bovine BMP7 gene.

    PubMed

    Huang, Yong-Zhen; Wang, Xin-Lei; He, Hua; Lan, Xian-Yong; Lei, Chu-Zhao; Zhang, Chun-Lei; Chen, Hong

    2013-12-15

    Bone morphogenetic proteins (BMPs) are peptide growth factors belonging to the transforming growth factor-beta (TGF-β) superfamily, and some members of the BMP family support white adipocyte differentiation. In this study, we focused on the BMP7 which singularly promotes the differentiation of brown preadipocytes. Haplotypes involving 5 single nucleotide polymorphism (SNP) sites in the bovine BMP7 gene were identified and their effect on body weight was analyzed. 16 haplotypes and 18 combined haplotypes were revealed and the linkage disequilibrium was assessed in the cattle population with 602 individuals representing three main cattle breeds from China. The results showed that haplotypes 3, 10 and 14 were predominant and accounted for 75.64%, 69.85%, and 83.36% in Nanyang, Qinchuan and Jiaxian cattle breeds, respectively. The statistical analyses indicated that the SNP 1, 4, and 5 are associated with the body weight, body length, and heart girth at 12 and 24 months in Nanyang cattle population (P<0.05), whereas there is no significant association between their 16 haplotypes and 18 combined haplotypes. Our results provide evidence that some SNPs and haplotypes in BMP7 are associated with growth traits, and may be utilized as a genetic marker in marker-assisted selection for beef cattle breeding programs. PMID:23500594

  10. Analysis of 22 Y chromosomal STR haplotypes and Y haplogroup distribution in Pathans of Pakistan.

    PubMed

    Lee, Eun Young; Shin, Kyoung-Jin; Rakha, Allah; Sim, Jeong Eun; Park, Myung Jin; Kim, Na Young; Yang, Woo Ick; Lee, Hwan Young

    2014-07-01

    We analyzed haplotypes for 22 Y chromosomal STRs (Y-STRs), including 17 Yfiler loci (DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DY438, DYS439, DYS448, DYS456, DYS458, DYS635 and Y-GATA-H4) and five additional STRs (DYS388, DYS446, DYS447, DYS449 and DYS464), and Y chromosomal haplogroup distribution in 270 unrelated individuals from the Pathans residing in the Federally Administered Tribal Areas and the North-West Frontier Province of Pakistan using in-house multiplex PCR systems. Each Y-STR showed diversities ranging from 0.2506 to 0.8538, and the discriminatory capacity (DC) was 73.7% with 199 observed haplotypes using 17 Yfiler loci. By the addition of 5 Y-STRs to the Yfiler system, the DC was increased to 85.2% while showing 230 observed haplotypes. Among the additional 5 Y-STRs, DYS446, DYS447 and DYS449 were major contributors to enhancing discrimination. In the analysis of molecular variance, the Pathans of this study showed significant differences from other Pathan populations as well as neighboring population sets. In Y-SNP analysis, a total of 12 Y chromosomal haplogroups were observed and the most frequent haplogroup was R1a1a with 49.3% frequency. To obtain insights on the origin of Pathans, the network analysis was performed for the haplogroups G and Q observed from the Pathans and the Jewish population groups including Ashkenazim and Sephardim, but little support for a Jewish origin could be found. In the present study, we report Y-STR population data in Pathans of Pakistan, and we emphasize the need for adding additional markers to the commonly used 17 Yfiler loci to achieve more improved discriminatory capacity in a population with low genetic diversity. PMID:24709582

  11. Application of a posteriori granddaughter and modified granddaughter designs to determine Holstein haplotype effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A posteriori and modified granddaughter designs were applied to determine haplotype effects for Holstein bulls and cows with BovineSNP50 genotypes. The a posteriori granddaughter design was applied to 52 sire families, each with >100 genotyped sons with genetic evaluations based on progeny tests. Fo...

  12. Application of a posteriori granddaughter and modified granddaughter designs to determine Holstein haplotype effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A posteriori and modified granddaughter designs were applied to determine haplotype effects for Holstein bulls and cows with BovineSNP50 genotypes. The a posteriori granddaughter design was applied to 52 sire families, each with '100 genotyped sons with genetic evaluations based on progeny tests. Fo...

  13. Influence of MDM2 SNP309 and SNP285 status on the risk of cancer in the breast, prostate, lung and colon.

    PubMed

    Gansmo, Liv B; Knappskog, Stian; Romundstad, Pål; Hveem, Kristian; Vatten, Lars; Lønning, Per E

    2015-07-01

    MDM2 is a key regulator of the p53 tumor suppressor protein and is overexpressed in many human cancers. Two single nucleotide polymorphisms (SNPs) located in the MDM2 intronic promoter (P2) have been found to exert biological function. The G-allele of SNP309T>G; rs2279744 increases MDM2 transcription and has been linked to increased cancer risk. In contrast, the less frequent SNP285G>C; rs117039649, which is in complete linkage disequilibrium with SNP309 (generating a SNP285C/309G variant haplotype), has been related to reduced MDM2 transcription and to reduced risk of breast, endometrial and ovarian cancer. In this large population-based case-control study, we genotyped SNP309 and SNP285 in 10,830 individuals, including cases with cancer of the breast (n=1,717), colon (n=1,532), lung (n=1,331) and prostate (n=2,501), as well as 3,749 non-cancer controls. We found a slightly reduced risk for lung cancer among individuals harboring the SNP309TG/GG genotypes compared to the SNP309TT genotype (OR= 0.86; CI = 0.67-0.98), but this association was restricted to women (OR = 0.77; CI = 0.63-0.95) and was not present among men (OR = 0.91; CI = 0.77-1.08). Consistent with previous findings, we found a reduced risk for breast cancer among individuals carrying the SNP285GC/309GG genotype versus the SNP285GG/309GG genotype (OR = 0.55; CI = 0.33-0.93). In conclusion, our data support the hypothesis that the effects of both SNP285 and SNP309 status are tissue dependent. PMID:25431177

  14. SNP panels/Imputation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Participants from thirteen countries discussed services that Interbull can perform or recommendations that Interbull can make to promote harmonization and assist member countries in improving their genomic evaluations in regard to SNP panels and imputation. The panel recommended: A mechanism to shar...

  15. Validation of SNP Allele Frequencies Determined by Pooled Next-Generation Sequencing in Natural Populations of a Non-Model Plant Species

    PubMed Central

    Rellstab, Christian; Zoller, Stefan; Tedder, Andrew; Gugerli, Felix; Fischer, Martin C.

    2013-01-01

    Sequencing of pooled samples (Pool-Seq) using next-generation sequencing technologies has become increasingly popular, because it represents a rapid and cost-effective method to determine allele frequencies for single nucleotide polymorphisms (SNPs) in population pools. Validation of allele frequencies determined by Pool-Seq has been attempted using an individual genotyping approach, but these studies tend to use samples from existing model organism databases or DNA stores, and do not validate a realistic setup for sampling natural populations. Here we used pyrosequencing to validate allele frequencies determined by Pool-Seq in three natural populations of Arabidopsis halleri (Brassicaceae). The allele frequency estimates of the pooled population samples (consisting of 20 individual plant DNA samples) were determined after mapping Illumina reads to (i) the publicly available, high-quality reference genome of a closely related species (Arabidopsis thaliana) and (ii) our own de novo draft genome assembly of A. halleri. We then pyrosequenced nine selected SNPs using the same individuals from each population, resulting in a total of 540 samples. Our results show a highly significant and accurate relationship between pooled and individually determined allele frequencies, irrespective of the reference genome used. Allele frequencies differed on average by less than 4%. There was no tendency that either the Pool-Seq or the individual-based approach resulted in higher or lower estimates of allele frequencies. Moreover, the rather high coverage in the mapping to the two reference genomes, ranging from 55 to 284x, had no significant effect on the accuracy of the Pool-Seq. A resampling analysis showed that only very low coverage values (below 10-20x) would substantially reduce the precision of the method. We therefore conclude that a pooled re-sequencing approach is well suited for analyses of genetic variation in natural populations. PMID:24244686

  16. Complete MHC haplotype sequencing for common disease gene mapping.

    PubMed

    Stewart, C Andrew; Horton, Roger; Allcock, Richard J N; Ashurst, Jennifer L; Atrazhev, Alexey M; Coggill, Penny; Dunham, Ian; Forbes, Simon; Halls, Karen; Howson, Joanna M M; Humphray, Sean J; Hunt, Sarah; Mungall, Andrew J; Osoegawa, Kazutoyo; Palmer, Sophie; Roberts, Anne N; Rogers, Jane; Sims, Sarah; Wang, Yu; Wilming, Laurens G; Elliott, John F; de Jong, Pieter J; Sawcer, Stephen; Todd, John A; Trowsdale, John; Beck, Stephan

    2004-06-01

    The future systematic mapping of variants that confer susceptibility to common diseases requires the construction of a fully informative polymorphism map. Ideally, every base pair of the genome would be sequenced in many individuals. Here, we report 4.75 Mb of contiguous sequence for each of two common haplotypes of the major histocompatibility complex (MHC), to which susceptibility to >100 diseases has been mapped. The autoimmune disease-associated-haplotypes HLA-A3-B7-Cw7-DR15 and HLA-A1-B8-Cw7-DR3 were sequenced in their entirety through a bacterial artificial chromosome (BAC) cloning strategy using the consanguineous cell lines PGF and COX, respectively. The two sequences were annotated to encompass all described splice variants of expressed genes. We defined the complete variation content of the two haplotypes, revealing >18,000 variations between them. Average SNP densities ranged from less than one SNP per kilobase to >60. Acquisition of complete and accurate sequence data over polymorphic regions such as the MHC from large-insert cloned DNA provides a definitive resource for the construction of informative genetic maps, and avoids the limitation of chromosome regions that are refractory to PCR amplification. PMID:15140828

  17. HLA Type Inference via Haplotypes Identical by Descent

    NASA Astrophysics Data System (ADS)

    Setty, Manu N.; Gusev, Alexander; Pe'Er, Itsik

    The Human Leukocyte Antigen (HLA) genes play a major role in adaptive immune response and are used to differentiate self antigens from non self ones. HLA genes are hyper variable with nearly every locus harboring over a dozen alleles. This variation plays an important role in susceptibility to multiple autoimmune diseases and needs to be matched on for organ transplantation. Unfortunately, HLA typing by serological methods is time consuming and expensive compared to high throughput Single Nucleotide Polymorphism (SNP) data. We present a new computational method to infer per-locus HLA types using shared segments Identical By Descent (IBD), inferred from SNP genotype data. IBD information is modeled as graph where shared haplotypes are explored among clusters of individuals with known and unknown HLA types to identify the latter. We analyze performance of the method in a previously typed subset of the HapMap population, achieving accuracy of 96% in HLA-A, 94% in HLA-B, 95% in HLA-C, 77% in HLA-DR1, 93% in HLA-DQA1 and 90% in HLA-DQB1 genes. We compare our method to a tag SNP based approach and demonstrate higher sensitivity and specificity. Our method demonstrates the power of using shared haplotype segments for large-scale imputation at the HLA locus.

  18. Genotyping NAT2 with only two SNPs (rs1041983 and rs1801280) outperforms the tagging SNP rs1495741 and is equivalent to the conventional 7-SNP NAT2 genotype.

    PubMed

    Selinski, Silvia; Blaszkewicz, Meinolf; Lehmann, Marie-Louise; Ovsiannikov, Daniel; Moormann, Oliver; Guballa, Christoph; Kress, Alexander; Truss, Michael C; Gerullis, Holger; Otto, Thomas; Barski, Dimitri; Niegisch, Günter; Albers, Peter; Frees, Sebastian; Brenner, Walburgis; Thüroff, Joachim W; Angeli-Greaves, Miriam; Seidel, Thilo; Roth, Gerhard; Dietrich, Holger; Ebbinghaus, Rainer; Prager, Hans M; Bolt, Hermann M; Falkenstein, Michael; Zimmermann, Anna; Klein, Torsten; Reckwitz, Thomas; Roemer, Hermann C; Löhlein, Dietrich; Weistenhöfer, Wobbeke; Schöps, Wolfgang; Hassan Rizvi, Syed Adibul; Aslam, Muhammad; Bánfi, Gergely; Romics, Imre; Steffens, Michael; Ekici, Arif B; Winterpacht, Andreas; Ickstadt, Katja; Schwender, Holger; Hengstler, Jan G; Golka, Klaus

    2011-10-01

    Genotyping N-acetyltransferase 2 (NAT2) is of high relevance for individualized dosing of antituberculosis drugs and bladder cancer epidemiology. In this study we compared a recently published tagging single nucleotide polymorphism (SNP) (rs1495741) to the conventional 7-SNP genotype (G191A, C282T, T341C, C481T, G590A, A803G and G857A haplotype pairs) and systematically analysed if novel SNP combinations outperform the latter. For this purpose, we studied 3177 individuals by PCR and phenotyped 344 individuals by the caffeine test. Although the tagSNP and the 7-SNP genotype showed a high degree of correlation (R=0.933, P<0.0001) the 7-SNP genotype nevertheless outperformed the tagging SNP with respect to specificity (1.0 vs. 0.9444, P=0.0065). Considering all possible SNP combinations in a receiver operating characteristic analysis we identified a 2-SNP genotype (C282T, T341C) that outperformed the tagging SNP and was equivalent to the 7-SNP genotype. The 2-SNP genotype predicted the correct phenotype with a sensitivity of 0.8643 and a specificity of 1.0. In addition, it predicted the 7-SNP genotype with sensitivity and specificity of 0.9993 and 0.9880, respectively. The prediction of the NAT2 genotype by the 2-SNP genotype performed similar in populations of Caucasian, Venezuelan and Pakistani background. A 2-SNP genotype predicts NAT2 phenotypes with similar sensitivity and specificity as the conventional 7-SNP genotype. This procedure represents a facilitation in individualized dosing of NAT2 substrates without losing sensitivity or specificity. PMID:21750470

  19. General Framework for Meta-Analysis of Haplotype Association Tests.

    PubMed

    Wang, Shuai; Zhao, Jing Hua; An, Ping; Guo, Xiuqing; Jensen, Richard A; Marten, Jonathan; Huffman, Jennifer E; Meidtner, Karina; Boeing, Heiner; Campbell, Archie; Rice, Kenneth M; Scott, Robert A; Yao, Jie; Schulze, Matthias B; Wareham, Nicholas J; Borecki, Ingrid B; Province, Michael A; Rotter, Jerome I; Hayward, Caroline; Goodarzi, Mark O; Meigs, James B; Dupuis, Josée

    2016-04-01

    For complex traits, most associated single nucleotide variants (SNV) discovered to date have a small effect, and detection of association is only possible with large sample sizes. Because of patient confidentiality concerns, it is often not possible to pool genetic data from multiple cohorts, and meta-analysis has emerged as the method of choice to combine results from multiple studies. Many meta-analysis methods are available for single SNV analyses. As new approaches allow the capture of low frequency and rare genetic variation, it is of interest to jointly consider multiple variants to improve power. However, for the analysis of haplotypes formed by multiple SNVs, meta-analysis remains a challenge, because different haplotypes may be observed across studies. We propose a two-stage meta-analysis approach to combine haplotype analysis results. In the first stage, each cohort estimate haplotype effect sizes in a regression framework, accounting for relatedness among observations if appropriate. For the second stage, we use a multivariate generalized least square meta-analysis approach to combine haplotype effect estimates from multiple cohorts. Haplotype-specific association tests and a global test of independence between haplotypes and traits are obtained within our framework. We demonstrate through simulation studies that we control the type-I error rate, and our approach is more powerful than inverse variance weighted meta-analysis of single SNV analysis when haplotype effects are present. We replicate a published haplotype association between fasting glucose-associated locus (G6PC2) and fasting glucose in seven studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium and we provide more precise haplotype effect estimates. PMID:27027517

  20. Exhaustive Genome-Wide Search for SNP-SNP Interactions Across 10 Human Diseases.

    PubMed

    Murk, William; DeWan, Andrew T

    2016-01-01

    The identification of statistical SNP-SNP interactions may help explain the genetic etiology of many human diseases, but exhaustive genome-wide searches for these interactions have been difficult, due to a lack of power in most datasets. We aimed to use data from the Resource for Genetic Epidemiology Research on Adult Health and Aging (GERA) study to search for SNP-SNP interactions associated with 10 common diseases. FastEpistasis and BOOST were used to evaluate all pairwise interactions among approximately N = 300,000 single nucleotide polymorphisms (SNPs) with minor allele frequency (MAF) ≥ 0.15, for the dichotomous outcomes of allergic rhinitis, asthma, cardiac disease, depression, dermatophytosis, type 2 diabetes, dyslipidemia, hemorrhoids, hypertensive disease, and osteoarthritis. A total of N = 45,171 subjects were included after quality control steps were applied. These data were divided into discovery and replication subsets; the discovery subset had > 80% power, under selected models, to detect genome-wide significant interactions (P < 10(-12)). Interactions were also evaluated for enrichment in particular SNP features, including functionality, prior disease relevancy, and marginal effects. No interaction in any disease was significant in both the discovery and replication subsets. Enrichment analysis suggested that, for some outcomes, interactions involving SNPs with marginal effects were more likely to be nominally replicated, compared to interactions without marginal effects. If SNP-SNP interactions play a role in the etiology of the studied conditions, they likely have weak effect sizes, involve lower-frequency variants, and/or involve complex models of interaction that are not captured well by the methods that were utilized. PMID:27185397

  1. Exhaustive Genome-Wide Search for SNP-SNP Interactions Across 10 Human Diseases

    PubMed Central

    Murk, William; DeWan, Andrew T.

    2016-01-01

    The identification of statistical SNP-SNP interactions may help explain the genetic etiology of many human diseases, but exhaustive genome-wide searches for these interactions have been difficult, due to a lack of power in most datasets. We aimed to use data from the Resource for Genetic Epidemiology Research on Adult Health and Aging (GERA) study to search for SNP-SNP interactions associated with 10 common diseases. FastEpistasis and BOOST were used to evaluate all pairwise interactions among approximately N = 300,000 single nucleotide polymorphisms (SNPs) with minor allele frequency (MAF) ≥ 0.15, for the dichotomous outcomes of allergic rhinitis, asthma, cardiac disease, depression, dermatophytosis, type 2 diabetes, dyslipidemia, hemorrhoids, hypertensive disease, and osteoarthritis. A total of N = 45,171 subjects were included after quality control steps were applied. These data were divided into discovery and replication subsets; the discovery subset had > 80% power, under selected models, to detect genome-wide significant interactions (P < 10−12). Interactions were also evaluated for enrichment in particular SNP features, including functionality, prior disease relevancy, and marginal effects. No interaction in any disease was significant in both the discovery and replication subsets. Enrichment analysis suggested that, for some outcomes, interactions involving SNPs with marginal effects were more likely to be nominally replicated, compared to interactions without marginal effects. If SNP-SNP interactions play a role in the etiology of the studied conditions, they likely have weak effect sizes, involve lower-frequency variants, and/or involve complex models of interaction that are not captured well by the methods that were utilized. PMID:27185397

  2. MHC Class II haplotypes of Colombian Amerindian tribes

    PubMed Central

    Yunis, Juan J.; Yunis, Edmond J.; Yunis, Emilio

    2013-01-01

    We analyzed 1041 individuals belonging to 17 Amerindian tribes of Colombia, Chimila, Bari and Tunebo (Chibcha linguistic family), Embera, Waunana (Choco linguistic family), Puinave and Nukak (Maku-Puinave linguistic families), Cubeo, Guanano, Tucano, Desano and Piratapuyo (Tukano linguistic family), Guahibo and Guayabero (Guayabero Linguistic Family), Curripaco and Piapoco (Arawak linguistic family) and Yucpa (Karib linguistic family). for MHC class II haplotypes (HLA-DRB1, DQA1, DQB1). Approximately 90% of the MHC class II haplotypes found among these tribes are haplotypes frequently encountered in other Amerindian tribes. Nonetheless, striking differences were observed among Chibcha and non-Chibcha speaking tribes. The DRB1*04:04, DRB1*04:11, DRB1*09:01 carrying haplotypes were frequently found among non-Chibcha speaking tribes, while the DRB1*04:07 haplotype showed significant frequencies among Chibcha speaking tribes, and only marginal frequencies among non-Chibcha speaking tribes. Our results suggest that the differences in MHC class II haplotype frequency found among Chibcha and non-Chibcha speaking tribes could be due to genetic differentiation in Mesoamerica of the ancestral Amerindian population into Chibcha and non-Chibcha speaking populations before they entered into South America. PMID:23885196

  3. Haplotypes of angiotensinogen in essential hypertension.

    PubMed Central

    Jeunemaitre, X; Inoue, I; Williams, C; Charru, A; Tichet, J; Powers, M; Sharma, A M; Gimenez-Roqueplo, A P; Hata, A; Corvol, P; Lalouel, J M

    1997-01-01

    The M235T polymorphism of the angiotensinogen gene (AGT) has been associated with essential and pregnancy-induced hypertension. Generation of haplotypes can help to resolve whether the T235 allele itself predisposes to the development of hypertension or acts as a marker of an unknown causal molecular variant. We identified 10 diallelic polymorphisms at the AGT locus and genotyped both a series of 477 probands of hypertensive families and 364 controls, all French Caucasians, as well as a series of 92 hypertensives and 122 controls from Japan. Despite a large ethnic difference in gene frequency, a significant association of T235 with hypertension was observed both in Cancasians (.46 vs. .38, P = .004) and in Japanese (.91 vs. .76, P = .002). In both groups, the G-->A substitution located at position -6 upstream of the initial transcription site occurred at the same frequency and in complete linkage disequilibrium with the T235 allele. No other polymorphism was found to be consistently associated with hypertension. Five informative haplotypes subdividing the T235 allele were generated. Whereas two of them were associated with hypertension in Caucasians, none of these two haplotypes (H3 and H4) reached statistical significance in Japanese. The analysis of the AGT-GT repeat revealed marked linkage disequilibriums between each of the diallelic polymorphisms and some (GT)n alleles, with similar patterns in the two populations. The strong disequilibrium between M235 and (GT)16 explained the increased frequency of that particular allele in French controls compared with hypertensives (.42 vs. .36, P < .01). The haplotype combining the M235T and G-6A polymorphisms appears as the ancestral allele of the human AGT gene and as the one associated with hypertension. PMID:9199566

  4. Toward understanding MHC disease associations: partial resequencing of 46 distinct HLA haplotypes.

    PubMed

    Smith, Wade P; Vu, Quyen; Li, Shuying Sue; Hansen, John A; Zhao, Lue Ping; Geraghty, Daniel E

    2006-05-01

    We carried out a resequencing project that examined 552 kb of sequence from each of 46 individual HLA haplotypes representing a diversity of HLA allele types, generating nearly 27 Mb of fully phased genomic sequence. Haplotype blocks were defined extending from telomeric of HLA-F to centromeric of HLA-DP including in total 5186 MHC SNPs. To investigate basic questions about the evolutionary origin of common HLA haplotypes, and to obtain an estimate of rare variation in the MHC, we similarly examined two additional sets of samples. In 19 independent HLA-A1, B8, DR3 chromosomes, the most common HLA haplotype in Northern European Caucasians, variation was found at 11 SNP positions in the 3600-kb region from HLA-A to DR. Partial resequencing of 282 individuals in the gene-dense class III region identified significant variability beyond what could have been detected by linkage to common SNPs. PMID:16434165

  5. A system for exact and approximate genetic linkage analysis of SNP data in large pedigrees

    PubMed Central

    Silberstein, Mark; Weissbrod, Omer; Otten, Lars; Tzemach, Anna; Anisenia, Andrei; Shtark, Oren; Tuberg, Dvir; Galfrin, Eddie; Gannon, Irena; Shalata, Adel; Borochowitz, Zvi U.; Dechter, Rina; Thompson, Elizabeth; Geiger, Dan

    2013-01-01

    Motivation: The use of dense single nucleotide polymorphism (SNP) data in genetic linkage analysis of large pedigrees is impeded by significant technical, methodological and computational challenges. Here we describe Superlink-Online SNP, a new powerful online system that streamlines the linkage analysis of SNP data. It features a fully integrated flexible processing workflow comprising both well-known and novel data analysis tools, including SNP clustering, erroneous data filtering, exact and approximate LOD calculations and maximum-likelihood haplotyping. The system draws its power from thousands of CPUs, performing data analysis tasks orders of magnitude faster than a single computer. By providing an intuitive interface to sophisticated state-of-the-art analysis tools coupled with high computing capacity, Superlink-Online SNP helps geneticists unleash the potential of SNP data for detecting disease genes. Results: Computations performed by Superlink-Online SNP are automatically parallelized using novel paradigms, and executed on unlimited number of private or public CPUs. One novel service is large-scale approximate Markov Chain–Monte Carlo (MCMC) analysis. The accuracy of the results is reliably estimated by running the same computation on multiple CPUs and evaluating the Gelman–Rubin Score to set aside unreliable results. Another service within the workflow is a novel parallelized exact algorithm for inferring maximum-likelihood haplotyping. The reported system enables genetic analyses that were previously infeasible. We demonstrate the system capabilities through a study of a large complex pedigree affected with metabolic syndrome. Availability: Superlink-Online SNP is freely available for researchers at http://cbl-hap.cs.technion.ac.il/superlink-snp. The system source code can also be downloaded from the system website. Contact: omerw@cs.technion.ac.il Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23162081

  6. Dimensional Anxiety Mediates Linkage of GABRA2 Haplotypes With Alcoholism

    PubMed Central

    Enoch, Mary-Anne; Schwartz, Lori; Albaugh, Bernard; Virkkunen, Matti; Goldman, David

    2015-01-01

    The GABAAα2 receptor gene (GABRA2) modulates anxiety and stress response. Three recent association studies implicate GABRA2 in alcoholism, however in these papers both common, opposite-configuration haplotypes in the region distal to intron3 predict risk. We have now replicated the GABRA2 association with alcoholism in 331 Plains Indian men and women and 461 Finnish Caucasian men. Using a dimensional measure of anxiety, harm avoidance (HA), we also found that the association with alcoholism is mediated, or moderated, by anxiety. Nine SNPs were genotyped revealing two haplotype blocks. Within the previously implicated block 2 region, we identified the two common, opposite-configuration risk haplotypes, A and B. Their frequencies differed markedly in Finns and Plains Indians. In both populations, most block 2 SNPs were significantly associated with alcoholism. The associations were due to increased frequencies of both homozygotes in alcoholics, indicating the possibility of alcoholic subtypes with opposite genotypes. Congruently, there was no significant haplotype association. Using HA as an indicator variable for anxiety, we found haplotype linkage to alcoholism with high and low dimensional anxiety, and to HA itself, in both populations. High HA alcoholics had the highest frequency of the more abundant haplotype (A in Finns, B in Plains Indians); low HA alcoholics had the highest frequency of the less abundant haplotype (B in Finns, A in Plains Indians) (Finns: P α0.007, OR α2.1, Plains Indians: P α0.040, OR α1.9). Non-alcoholics had intermediate frequencies. Our results suggest that within the distal GABRA2 region is a functional locus or loci that may differ between populations but that alters risk for alcoholism via the mediating action of anxiety. PMID:16874763

  7. Dimensional anxiety mediates linkage of GABRA2 haplotypes with alcoholism.

    PubMed

    Enoch, Mary-Anne; Schwartz, Lori; Albaugh, Bernard; Virkkunen, Matti; Goldman, David

    2006-09-01

    The GABAAalpha2 receptor gene (GABRA2) modulates anxiety and stress response. Three recent association studies implicate GABRA2 in alcoholism, however in these papers both common, opposite-configuration haplotypes in the region distal to intron3 predict risk. We have now replicated the GABRA2 association with alcoholism in 331 Plains Indian men and women and 461 Finnish Caucasian men. Using a dimensional measure of anxiety, harm avoidance (HA), we also found that the association with alcoholism is mediated, or moderated, by anxiety. Nine SNPs were genotyped revealing two haplotype blocks. Within the previously implicated block 2 region, we identified the two common, opposite-configuration risk haplotypes, A and B. Their frequencies differed markedly in Finns and Plains Indians. In both populations, most block 2 SNPs were significantly associated with alcoholism. The associations were due to increased frequencies of both homozygotes in alcoholics, indicating the possibility of alcoholic subtypes with opposite genotypes. Congruently, there was no significant haplotype association. Using HA as an indicator variable for anxiety, we found haplotype linkage to alcoholism with high and low dimensional anxiety, and to HA itself, in both populations. High HA alcoholics had the highest frequency of the more abundant haplotype (A in Finns, B in Plains Indians); low HA alcoholics had the highest frequency of the less abundant haplotype (B in Finns, A in Plains Indians) (Finns: P = 0.007, OR = 2.1, Plains Indians: P = 0.040, OR = 1.9). Non-alcoholics had intermediate frequencies. Our results suggest that within the distal GABRA2 region is a functional locus or loci that may differ between populations but that alters risk for alcoholism via the mediating action of anxiety. PMID:16874763

  8. Selection of minimum subsets of single nucleotide polymorphisms to capture haplotype block diversity.

    PubMed

    Avi-Itzhak, Hadar I; Su, Xiaoping; De La Vega, Francisco M

    2003-01-01

    We present a simple numerical algorithm to select the minimal subset of SNPs required to capture the diversity of haplotype blocks or other genetic loci. This algorithm can be used to quickly select the minimum SNP subset with no loss of haplotype information. In addition, the method can be used in a more aggressive mode to further reduce the original SNP set, with minimal loss of information. We demonstrate the algorithm performance with data from over 11,000 SNPs with average spacing of 6 to 11 Kb, across all the genes of chromosomes 6, 21, and 22, genotyped on DNA samples of 45 unrelated African-Americans and 45 Caucasians from the Coriell Human Diversity Collection. With no loss of information, we reduced the number of SNPs required to capture the haplotype block diversity by 25% for the African-American and 36% for the Caucasian populations. With a maximum loss of 10% of haplotype distribution information, the SNP reduction was 38% and 49% respectively for the two populations. All computations were performed in less than 1 minute for the entire dataset used. PMID:12603050

  9. Bootstrap study of genome-enabled prediction reliabilities using haplotype blocks across Nordic Red cattle breeds.

    PubMed

    Cuyabano, B C D; Su, G; Rosa, G J M; Lund, M S; Gianola, D

    2015-10-01

    This study compared the accuracy of genome-enabled prediction models using individual single nucleotide polymorphisms (SNP) or haplotype blocks as covariates when using either a single breed or a combined population of Nordic Red cattle. The main objective was to compare predictions of breeding values of complex traits using a combined training population with haplotype blocks, with predictions using a single breed as training population and individual SNP as predictors. To compare the prediction reliabilities, bootstrap samples were taken from the test data set. With the bootstrapped samples of prediction reliabilities, we built and graphed confidence ellipses to allow comparisons. Finally, measures of statistical distances were used to calculate the gain in predictive ability. Our analyses are innovative in the context of assessment of predictive models, allowing a better understanding of prediction reliabilities and providing a statistical basis to effectively calibrate whether one prediction scenario is indeed more accurate than another. An ANOVA indicated that use of haplotype blocks produced significant gains mainly when Bayesian mixture models were used but not when Bayesian BLUP was fitted to the data. Furthermore, when haplotype blocks were used to train prediction models in a combined Nordic Red cattle population, we obtained up to a statistically significant 5.5% average gain in prediction accuracy, over predictions using individual SNP and training the model with a single breed. PMID:26233439

  10. Sequence-Level Analysis of the Major European Huntington Disease Haplotype

    PubMed Central

    Lee, Jong-Min; Kim, Kyung-Hee; Shin, Aram; Chao, Michael J.; Abu Elneel, Kawther; Gillis, Tammy; Mysore, Jayalakshmi Srinidhi; Kaye, Julia A.; Zahed, Hengameh; Kratter, Ian H.; Daub, Aaron C.; Finkbeiner, Steven; Li, Hong; Roach, Jared C.; Goodman, Nathan; Hood, Leroy; Myers, Richard H.; MacDonald, Marcy E.; Gusella, James F.

    2015-01-01

    Huntington disease (HD) reflects the dominant consequences of a CAG-repeat expansion in HTT. Analysis of common SNP-based haplotypes has revealed that most European HD subjects have distinguishable HTT haplotypes on their normal and disease chromosomes and that ∼50% of the latter share the same major HD haplotype. We reasoned that sequence-level investigation of this founder haplotype could provide significant insights into the history of HD and valuable information for gene-targeting approaches. Consequently, we performed whole-genome sequencing of HD and control subjects from four independent families in whom the major European HD haplotype segregates with the disease. Analysis of the full-sequence-based HTT haplotype indicated that these four families share a common ancestor sufficiently distant to have permitted the accumulation of family-specific variants. Confirmation of new CAG-expansion mutations on this haplotype suggests that unlike most founders of human disease, the common ancestor of HD-affected families with the major haplotype most likely did not have HD. Further, availability of the full sequence data validated the use of SNP imputation to predict the optimal variants for capturing heterozygosity in personalized allele-specific gene-silencing approaches. As few as ten SNPs are capable of revealing heterozygosity in more than 97% of European HD subjects. Extension of allele-specific silencing strategies to the few remaining homozygous individuals is likely to be achievable through additional known SNPs and discovery of private variants by complete sequencing of HTT. These data suggest that the current development of gene-based targeting for HD could be extended to personalized allele-specific approaches in essentially all HD individuals of European ancestry. PMID:26320893

  11. Sequence-Level Analysis of the Major European Huntington Disease Haplotype.

    PubMed

    Lee, Jong-Min; Kim, Kyung-Hee; Shin, Aram; Chao, Michael J; Abu Elneel, Kawther; Gillis, Tammy; Mysore, Jayalakshmi Srinidhi; Kaye, Julia A; Zahed, Hengameh; Kratter, Ian H; Daub, Aaron C; Finkbeiner, Steven; Li, Hong; Roach, Jared C; Goodman, Nathan; Hood, Leroy; Myers, Richard H; MacDonald, Marcy E; Gusella, James F

    2015-09-01

    Huntington disease (HD) reflects the dominant consequences of a CAG-repeat expansion in HTT. Analysis of common SNP-based haplotypes has revealed that most European HD subjects have distinguishable HTT haplotypes on their normal and disease chromosomes and that ∼50% of the latter share the same major HD haplotype. We reasoned that sequence-level investigation of this founder haplotype could provide significant insights into the history of HD and valuable information for gene-targeting approaches. Consequently, we performed whole-genome sequencing of HD and control subjects from four independent families in whom the major European HD haplotype segregates with the disease. Analysis of the full-sequence-based HTT haplotype indicated that these four families share a common ancestor sufficiently distant to have permitted the accumulation of family-specific variants. Confirmation of new CAG-expansion mutations on this haplotype suggests that unlike most founders of human disease, the common ancestor of HD-affected families with the major haplotype most likely did not have HD. Further, availability of the full sequence data validated the use of SNP imputation to predict the optimal variants for capturing heterozygosity in personalized allele-specific gene-silencing approaches. As few as ten SNPs are capable of revealing heterozygosity in more than 97% of European HD subjects. Extension of allele-specific silencing strategies to the few remaining homozygous individuals is likely to be achievable through additional known SNPs and discovery of private variants by complete sequencing of HTT. These data suggest that the current development of gene-based targeting for HD could be extended to personalized allele-specific approaches in essentially all HD individuals of European ancestry. PMID:26320893

  12. Compound inheritance of a low-frequency regulatory SNP and a rare null mutation in exon-junction complex subunit RBM8A causes TAR syndrome.

    PubMed

    Albers, Cornelis A; Paul, Dirk S; Schulze, Harald; Freson, Kathleen; Stephens, Jonathan C; Smethurst, Peter A; Jolley, Jennifer D; Cvejic, Ana; Kostadima, Myrto; Bertone, Paul; Breuning, Martijn H; Debili, Najet; Deloukas, Panos; Favier, Rémi; Fiedler, Janine; Hobbs, Catherine M; Huang, Ni; Hurles, Matthew E; Kiddle, Graham; Krapels, Ingrid; Nurden, Paquita; Ruivenkamp, Claudia A L; Sambrook, Jennifer G; Smith, Kenneth; Stemple, Derek L; Strauss, Gabriele; Thys, Chantal; van Geet, Chris; Newbury-Ecob, Ruth; Ouwehand, Willem H; Ghevaert, Cedric

    2012-04-01

    The exon-junction complex (EJC) performs essential RNA processing tasks. Here, we describe the first human disorder, thrombocytopenia with absent radii (TAR), caused by deficiency in one of the four EJC subunits. Compound inheritance of a rare null allele and one of two low-frequency SNPs in the regulatory regions of RBM8A, encoding the Y14 subunit of EJC, causes TAR. We found that this inheritance mechanism explained 53 of 55 cases (P < 5 × 10(-228)) of the rare congenital malformation syndrome. Of the 53 cases with this inheritance pattern, 51 carried a submicroscopic deletion of 1q21.1 that has previously been associated with TAR, and two carried a truncation or frameshift null mutation in RBM8A. We show that the two regulatory SNPs result in diminished RBM8A transcription in vitro and that Y14 expression is reduced in platelets from individuals with TAR. Our data implicate Y14 insufficiency and, presumably, an EJC defect as the cause of TAR syndrome. PMID:22366785

  13. General Framework for Meta‐Analysis of Haplotype Association Tests

    PubMed Central

    Wang, Shuai; Zhao, Jing Hua; An, Ping; Guo, Xiuqing; Jensen, Richard A.; Marten, Jonathan; Huffman, Jennifer E.; Meidtner, Karina; Boeing, Heiner; Campbell, Archie; Rice, Kenneth M.; Scott, Robert A.; Yao, Jie; Schulze, Matthias B.; Wareham, Nicholas J.; Borecki, Ingrid B.; Province, Michael A.; Rotter, Jerome I.; Hayward, Caroline; Goodarzi, Mark O.; Meigs, James B.

    2016-01-01

    ABSTRACT For complex traits, most associated single nucleotide variants (SNV) discovered to date have a small effect, and detection of association is only possible with large sample sizes. Because of patient confidentiality concerns, it is often not possible to pool genetic data from multiple cohorts, and meta‐analysis has emerged as the method of choice to combine results from multiple studies. Many meta‐analysis methods are available for single SNV analyses. As new approaches allow the capture of low frequency and rare genetic variation, it is of interest to jointly consider multiple variants to improve power. However, for the analysis of haplotypes formed by multiple SNVs, meta‐analysis remains a challenge, because different haplotypes may be observed across studies. We propose a two‐stage meta‐analysis approach to combine haplotype analysis results. In the first stage, each cohort estimate haplotype effect sizes in a regression framework, accounting for relatedness among observations if appropriate. For the second stage, we use a multivariate generalized least square meta‐analysis approach to combine haplotype effect estimates from multiple cohorts. Haplotype‐specific association tests and a global test of independence between haplotypes and traits are obtained within our framework. We demonstrate through simulation studies that we control the type‐I error rate, and our approach is more powerful than inverse variance weighted meta‐analysis of single SNV analysis when haplotype effects are present. We replicate a published haplotype association between fasting glucose‐associated locus (G6PC2) and fasting glucose in seven studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium and we provide more precise haplotype effect estimates. PMID:27027517

  14. Ethnicity-Related Polymorphisms and Haplotypes in the Human ABCB1 Gene

    PubMed Central

    Kimchi-Sarfaty, Chava; Marple, Andrew H; Shinar, Shiri; Kimchi, Avraham M.; Scavo, David; Roma, M. Isabella; Kim, In-Wha; Jones, Adam; Arora, Mili; Gribar, John; Gurwitz, David; Gottesman, Michael M

    2007-01-01

    Introduction The human multi-drug resistance gene (MDR1, ABCB1) codes for P-glycoprotein (P-gp), an important membrane-bound efflux transporter known to confer anti-cancer drug resistance as well as affect the pharmacokinetics of many drugs and xenobiotics. A number of single nucleotide polymorphisms (SNPs) have been identified throughout the ABCB1 gene which may have an effect on P-gp expression levels and function. Haplotype as well as genotype analysis of SNPs is becoming increasingly important in identifying genetic variants underlying susceptibility to human disease. Three SNPs, 1236C>T, 2677G>T, and 3435C>T have been repeatedly shown to predict changes in the function of P-gp. The frequencies with which these polymorphisms exist in a population have also been shown to be ethnically related. Methods In this study, 95 individuals representative of the entire ethnic make-up of the United States were compared to 101 individuals from an Ashkenazi Jewish population. These individuals were analyzed by genomic sequencing and PCR-RFLP to calculate their genotype frequencies. Results Twenty-five SNPs were located in the exons of the ABCB1 gene. All of the polymorphisms identified were in parts of the ABCB1 gene product predicted to be intracellular, and 16 appear to be novel as compared to those listed by NCBI. Frequencies of the 1236C>T and 2677G>T/A/C SNPs were similar for the American and Ashkenazi populations (64.2% and 60.4% respectively for 1236C>T – χ2 is 0.30 p≤1; 55.8% and 64.4% for 2677G>T/A/C χ2 is 1.49 p≤1), but were different for 3435C>T (24.2% for the American population and 69.3% for the Ashkenazi population χ2 is 39.927 p<0.001). The 1236T/2677T/3435T haplotype occurred in 23.6% (SE 0.013) of the Ashkenazi population. Conclusion The SNP at location 3435C>T plays a significant role in the ABCB1 gene. The haplotype and genotype analysis from these data may be used as a basis for studies on the relationship between ABCB1 genotypes and drug

  15. Novel Nucleotide Variations, Haplotypes Structure and Associations with Growth Related Traits of Goat AT Motif-Binding Factor (ATBF1) Gene

    PubMed Central

    Zhang, Xiaoyan; Wu, Xianfeng; Jia, Wenchao; Pan, Chuanying; Li, Xiangcheng; Lei, Chuzhao; Chen, Hong; Lan, Xianyong

    2015-01-01

    The AT motif-binding factor (ATBF1) not only interacts with protein inhibitor of activated signal transducer and activator of transcription 3 (STAT3) (PIAS3) to suppress STAT3 signaling regulating embryo early development and cell differentiation, but is required for early activation of the pituitary specific transcription factor 1 (Pit1) gene (also known as POU1F1) critically affecting mammalian growth and development. The goal of this study was to detect novel nucleotide variations and haplotypes structure of the ATBF1 gene, as well as to test their associations with growth-related traits in goats. Herein, a total of seven novel single nucleotide polymorphisms (SNPs) (SNP 1-7) within this gene were found in two well-known Chinese native goat breeds. Haplotypes structure analysis demonstrated that there were four haplotypes in Hainan black goat while seventeen haplotypes in Xinong Saanen dairy goat, and both breeds only shared one haplotype (hap1). Association testing revealed that the SNP2, SNP5, SNP6, and SNP7 loci were also found to significantly associate with growth-related traits in goats, respectively. Moreover, one diplotype in Xinong Saanen dairy goats significantly linked to growth related traits. These preliminary findings not only would extend the spectrum of genetic variations of the goat ATBF1 gene, but also would contribute to implementing marker-assisted selection in genetics and breeding in goats. PMID:26323396

  16. Haplotypes that include the integrin alpha 11 gene are associated with tick burden in cattle

    PubMed Central

    2010-01-01

    Background Infestations on cattle by the ectoparasite Boophilus (Rhipicephalus) microplus (cattle tick) impact negatively on animal production systems. Host resistance to tick infestation has a low to moderate heritability in the range 0.13 - 0.64 in Australia. Previous studies identified a QTL on bovine chromosome 10 (BTA10) linked to tick burden in cattle. Results To confirm these associations, we collected genotypes of 17 SNP from BTA10, including three obtained by sequencing part of the ITGA11 (Integrin alpha 11) gene. Initially, we genotyped 1,055 dairy cattle for the 17 SNP, and then genotyped 557 Brahman and 216 Tropical Composite beef cattle for 11 of the 17 SNP. In total, 7 of the SNP were significantly (P < 0.05) associated with tick burden tested in any of the samples. One SNP, ss161109814, was significantly (P < 0.05) associated with tick burden in both the taurine and the Brahman sample, but the favourable allele was different. Haplotypes for three and for 10 SNP were more significantly (P < 0.001) associated with tick burden than SNP analysed individually. Some of the common haplotypes with the largest sample sizes explained between 1.3% and 1.5% of the residual variance in tick burden. Conclusions These analyses confirm the location of a QTL affecting tick burden on BTA10 and position it close to the ITGA11 gene. The presence of a significant association in such widely divergent animals suggests that further SNP discovery in this region to detect causal mutations would be warranted. PMID:20565915

  17. Association of Nrf2 Polymorphism Haplotypes with Acute Lung Injury Phenotypes in Inbred Strains of Mice

    PubMed Central

    Jedlicka, Anne E.; Gladwell, Wesley; Marzec, Jacqui; McCaw, Zackary R.; Bienstock, Rachelle J.; Kleeberger, Steven R.

    2015-01-01

    Abstract Aims: Nrf2 is a master transcription factor for antioxidant response element (ARE)-mediated cytoprotective gene induction. A protective role for pulmonary Nrf2 was determined in model oxidative disorders, including hyperoxia-induced acute lung injury (ALI). To obtain additional insights into the function and genetic regulation of Nrf2, we assessed functional single nucleotide polymorphisms (SNPs) of Nrf2 in inbred mouse strains and tested whether sequence variation is associated with hyperoxia susceptibility. Results: Nrf2 SNPs were compiled from publicly available databases and by re-sequencing DNA from inbred strains. Hierarchical clustering of Nrf2 SNPs categorized the strains into three major haplotypes. Hyperoxia susceptibility was greater in haplotypes 2 and 3 strains than in haplotype 1 strains. A promoter SNP −103 T/C adding an Sp1 binding site in haplotype 2 diminished promoter activation basally and under hyperoxia. Haplotype 3 mice bearing nonsynonymous coding SNPs located in (1862 A/T, His543Gln) and adjacent to (1417 T/C, Thr395Ile) the Neh1 domain showed suppressed nuclear transactivation of pulmonary Nrf2 relative to other strains, and overexpression of haplotype 3 Nrf2 showed lower ARE responsiveness than overexpression of haplotype 1 Nrf2 in airway cells. Importantly, we found a significant correlation of Nrf2 haplotypes and hyperoxic lung injury phenotypes. Innovation and Conclusion: The results indicate significant influence of Nrf2 polymorphisms and haplotypes on gene function and hyperoxia susceptibility. Our findings further support Nrf2 as a genetic determinant in ALI pathogenesis and provide useful tools for investigators who use mouse strains classified by Nrf2 haplotypes to elucidate the role for Nrf2 in oxidative disorders. Antioxid. Redox Signal. 22, 325–338. PMID:25268541

  18. Haplotype-specific pattern of association of human major histocompatibility complex with non-Hodgkin's lymphoma outcome.

    PubMed

    Nowak, J; Kalinka-Warzocha, E; Juszczyński, P; Mika-Witkowska, R; Zajko, M; Graczyk-Pol, E; Coiffier, B; Salles, G; Warzocha, K

    2008-01-01

    In the previous studies, some human major histocompatibility complex (MHC) genes such as TNF, LTA and human leukocyte antigen (HLA)-DR2 genes and A1-B8-TNF(-308A) haplotype were implied in non-Hodgkin's lymphoma (NHL) outcome. In the current study, we have assigned most probable six-locus haplotypes determined by HLA-A, -Cw, -B and -DRB1 highly polymorphic genes and non-HLA LTA(+252) and TNF(-308) single nucleotide polymorphisms (SNPs) in 152 NHL Caucasian French patients. We have broadly mapped the MHC region by its component blocks and tagging alleles. Ten frequent (with haplotype frequency >1%) six-locus extended haplotypes (EHs) were revealed in NHL patients. The only two adjacent locus fragment of 8.1 EH associated with shortened freedom from progression (FFP) was B*08-LTA(+252G) (P= 0.0084, RR = 2.45). Interestingly, 305-kbp-long, four-locus fragment of 8.1 EH, Cw*07-B*08-LTA(+252G)-TNF(-308A) block was much strongly associated with shortened FFP (P= 0.00045, RR = 3.26). The analysis of further extended haploblocks comprising five or six loci showed weaker association with outcome measures, suggesting linkage disequilibrium to be the cause of DRB1*03 and A*01 allele associations. In contrast, all fragments of 7.1 EH influenced FFP favorably with top association of TNF(-308G) allele. In multivariate analysis, only Cw*07-B*08-LTA(+252G)-TNF(-308A) and TNF(-308G)-DRB1*01 haplotypes remained predictive for shortened FFP (P= 0.024 and 0.027, respectively) and independent of International Prognostic Index (P= 0.00044). This study reveals that the block composition of EHs may cause important functional differences for NHL outcomes. Further study will be required in NHL patients by fine mapping with dense microsatellite or SNP tags to define susceptibility genes in associating regions. PMID:17971052

  19. [Analysis of mitochondrial DNA haplotypes in yakut population].

    PubMed

    Fedorova, S A; Bermisheva, M A; Villems, R; Maksimova, N R; Khusnutdinova, E K

    2003-01-01

    To study the mitochondrial gene pool structure in Yakuts, polymorphism of mtDNA hypervariable segment I (16,024-16,390) was analyzed in 191 people sampled from the indigenous population of the Sakha Republic. In total, 67 haplotypes of 14 haplogroups were detected. Most (91.6%) haplotypes belonged to haplogroups A, B, C, D, F, G, M*, and Y, which are specific for East Eurasian ethnic groups; 8.4% haplotypes represented Caucasian haplogroups H, HV1, J, T, U, and W. A high frequency of mtDNA types belonging to Asian supercluster M was peculiar for Yakuts: mtDNA types belonging to haplogroup C, D, or G and undifferentiated mtDNA types of haplogroup M (M*) accounted for 81% of all haplotypes. The highest diversity was observed for haplogroups C and D, which comprised respectively 22 (44%) and 18 (30%) haplotypes. Yakuts showed the lowest genetic diversity (H = 0.964) among all Turkic ethnic groups. Phylogenetic analysis testified to a common genetic substrate of Yakuts, Mongols, and Central Asian (Kazakh, Kyrgyz, Uigur) populations. Yakuts proved to share 21 (55.5%) mtDNA haplogroups with the Central Asian ethnic groups and Mongols. Comparisons with modern paleo-Asian populations (Chukcha, Itelmen, Koryaks) revealed three (8.9%) haplotypes common for Yakuts and Koryaks. The results of mtDNA analysis disagree with the hypothesis of an appreciable paleo-Asian contribution to the modern Yakut gene pool. PMID:12942638

  20. Polymorphic DNA haplotypes at the LDL receptor locus.

    PubMed Central

    Leitersdorf, E; Chakravarti, A; Hobbs, H H

    1989-01-01

    Mutations in the low-density lipoprotein (LDL) receptor gene result in the autosomal dominant disorder familial hypercholesterolemia (FH). Many different LDL receptor mutations have been identified and characterized, demonstrating a high degree of allelic heterogeneity at this locus. The ability to identify mutant LDL receptor genes for prenatal diagnosis of homozygous FH or to study the role of the LDL receptor gene in polygenic hypercholesterolemia requires the use of closely linked RFLPs. In the present study we used 10 different RFLPs, including three newly described polymorphisms, to construct 123 independent haplotypes from 20 Caucasian American pedigrees. Our sample contained 31 different haplotypes varying in frequency from 0.8% to 29.3%; the five most common haplotypes account for 67.5% of the sample. The heterozygosity and PIC of each site were determined, and these values disclosed that eight of the RFLPs were substantially polymorphic. Linkage-disequilibrium analysis of the haplotype data revealed strong nonrandom associations among all 10 RFLPs, especially among those sites clustered in the 3' region of the gene. Evolutionary analysis suggests the occurrence of both mutational and recombinational events in the generation of the observed haplotypes. A strategy for haplotype analysis of the LDL receptor gene in individuals of Caucasian American descent is presented. Images Figure 2 Figure 3 PMID:2563635

  1. Evolution of haplotypes at the DRD2 locus

    SciTech Connect

    Castiglione, C.M.; Deinard, A.S.; Speed, W.C.

    1995-12-01

    We present here the first evolutionary perspective on haplotypes at DRD2, the locus for the dopamine D{sub 2} receptor. The dopamine D{sub 2} receptor plays a critical role in the functioning of many neural circuits in the human brain. If functionally relevant variation at the DRD2 locus exists, understanding the evolution of haplotypes on the basis of polymorphic sites encompassing the gene should provide a powerful framework for identifying that variation. Three DRD2 polymorphisms (TaqI {open_quotes}A{close_quotes} and {open_quotes}B{close_quotes} RFLPs and the (CA){sub n} short tandem repeat polymorphism) encompassing the coding sequences have been studied in 15 populations; these markers are polymorphic in all the populations studied, and they display strong and significant linkage disequilibria with each other. The common haplotypes for the two TaqI RFLPs are separately derived from the ancestral haplotype but predate the spread of modern humans around the world. The knowledge of how the various haplotypes have evolved, the allele frequencies of the haplotypes in human populations, and the physical relationships of the polymorphisms to each other and to the functional parts of the gene should now allow proper design and interpretation of association studies. 48 refs., 2 figs., 6 tabs.

  2. How Have Self-Incompatibility Haplotypes Diversified? Generation of New Haplotypes during the Evolution of Self-Incompatibility from Self-Compatibility.

    PubMed

    Sakai, Satoki

    2016-08-01

    I developed a gametophytic self-incompatibility (SI) model to study the conditions leading to diversification in SI haplotypes. In the model, the SI system is assumed to be incomplete, and the pollen expressing a given specificity is not fully rejected by the pistils expressing the same specificity. I also assumed that mutations can occur that enhance the rejection of pollen by pistils with the same haplotype variant and reduce rejection by pistils with other variants in the same haplotype. I found that if such mutations occur, the new haplotypes (mutant variants) can stably coexist with the ancestral haplotype in which the mutant arose. This is because pollen bearing the new haplotype is most strongly rejected by pistils bearing the same new haplotype among the pistils in the population; hence, negative frequency-dependent selection prevents their fixation. I also performed simulations and found that the nearly complete SI system evolves from completely self-compatible populations and that SI haplotypes can increase to about 40-50 within a few thousand generations. On the basis of my findings, I propose that diversification of SI haplotypes occurred during the evolution of SI from self-compatibility. PMID:27420782

  3. Y-STR haplotypes of Native American populations from the Brazilian Amazon region.

    PubMed

    Palha, Teresinha Jesus Brabo Ferreira; Rodrigues, Elzemar Martins Ribeiro; dos Santos, Sidney Emanuel Batista

    2010-10-01

    The allele and haplotype frequencies of nine Y-STRs (DYS19, DYS389 I, DYS389 II, DYS390, DYS391, DYS392, DYS393, DYS385 I/II) were determined in a sample of six native tribes from the Brazilian Amazon (Tiriyó, Awa-Guajá, Waiãpi, Urubu-Kaapor, Zoé and Parakanã). Forty-eight different haplotypes were identified, 28 of which unique. Five haplotypes are very frequent and were shared by over 10 individuals. The estimated haplotype diversity (0.9114) was very low compared to other geographic groups, including Africans, Europeans and Asians. PMID:20457062

  4. Reflections on ancestral haplotypes: medical genomics, evolution, and human individuality.

    PubMed

    Steele, Edward J

    2014-01-01

    The major histocompatibility complex (MHC), once labelled the "sphinx of immunology" by Jan Klein, provides powerful challenges to evolutionary thinking. This essay highlights the main discoveries that established the block ancestral haplotype structure of the MHC and the wider genome, focusing on the work by the Perth (Australia) group, led by Roger Dawkins, and the Boston group, led by Chester Alper and Edmond Yunis. Their achievements have been overlooked in the rush to sequence the first and subsequent drafts of the human genome. In Caucasoids, where most of the detailed work has been done, about 70% of all known allelic MHC diversity can be accounted for by 30 or so ancestral haplotypes (AHs), or conserved sequences of many mega-bases, and their recombinants. The block haplotype structure of the genome, as shown for the MHC (and other genetic regions), is a story that needs to be understood in its own right, particularly given the promotion of the "HapMap" project and single nucleotide polymorphism (SNP) linkage disequilibrium (LD) analysis, which has been wrongly touted as the only way to pinpoint those genes that are important in genetic disorders or other desired (qualitative) characteristics. PMID:25544323

  5. Intrahaplotypic Variants Differentiate Complex Linkage Disequilibrium within Human MHC Haplotypes

    PubMed Central

    Lam, Tze Hau; Tay, Matthew Zirui; Wang, Bei; Xiao, Ziwei; Ren, Ee Chee

    2015-01-01

    Distinct regions of long-range genetic fixation in the human MHC region, known as conserved extended haplotypes (CEHs), possess unique genomic characteristics and are strongly associated with numerous diseases. While CEHs appear to be homogeneous by SNP analysis, the nature of fine variations within their genomic structure is unknown. Using multiple, MHC-homozygous cell lines, we demonstrate extensive sequence conservation in two common Asian MHC haplotypes: A33-B58-DR3 and A2-B46-DR9. However, characterization of phase-resolved MHC haplotypes revealed unique intra-CEH patterns of variation and uncovered 127 single nucleotide variants (SNVs) which are missing from public databases. We further show that the strong linkage disequilibrium structure within the human MHC that typically confounds precise identification of genetic features can be resolved using intra-CEH variants, as evidenced by rs3129063 and rs448489, which affect expression of ZFP57, a gene important in methylation and epigenetic regulation. This study demonstrates an improved strategy that can be used towards genetic dissection of diseases. PMID:26593880

  6. Single nucleotide polymorphisms and haplotypes associated with feed efficiency in beef cattle

    PubMed Central

    2013-01-01

    Background General, breed- and diet-dependent associations between feed efficiency in beef cattle and single nucleotide polymorphisms (SNPs) or haplotypes were identified on a population of 1321 steers using a 50 K SNP panel. Genomic associations with traditional two-step indicators of feed efficiency – residual feed intake (RFI), residual average daily gain (RADG), and residual intake gain (RIG) – were compared to associations with two complementary one-step indicators of feed efficiency: efficiency of intake (EI) and efficiency of gain (EG). Associations uncovered in a training data set were evaluated on independent validation data set. A multi-SNP model was developed to predict feed efficiency. Functional analysis of genes harboring SNPs significantly associated with feed efficiency and network visualization aided in the interpretation of the results. Results For the five feed efficiency indicators, the numbers of general, breed-dependent, and diet-dependent associations with SNPs (P-value < 0.0001) were 31, 40, and 25, and with haplotypes were six, ten, and nine, respectively. Of these, 20 SNP and six haplotype associations overlapped between RFI and EI, and five SNP and one haplotype associations overlapped between RADG and EG. This result confirms the complementary value of the one and two-step indicators. The multi-SNP models included 89 SNPs and offered a precise prediction of the five feed efficiency indicators. The associations of 17 SNPs and 7 haplotypes with feed efficiency were confirmed on the validation data set. Nine clusters of Gene Ontology and KEGG pathway categories (mean P-value < 0.001) including, 9nucleotide binding; ion transport, phosphorous metabolic process, and the MAPK signaling pathway were overrepresented among the genes harboring the SNPs associated with feed efficiency. Conclusions The general SNP associations suggest that a single panel of genomic variants can be used regardless of breed and diet. The breed- and diet

  7. RNA-Seq identifies SNP markers for growth traits in rainbow trout.

    PubMed

    Salem, Mohamed; Vallejo, Roger L; Leeds, Timothy D; Palti, Yniv; Liu, Sixin; Sabbagh, Annas; Rexroad, Caird E; Yao, Jianbo

    2012-01-01

    Fast growth is an important and highly desired trait, which affects the profitability of food animal production, with feed costs accounting for the largest proportion of production costs. Traditional phenotype-based selection is typically used to select for growth traits; however, genetic improvement is slow over generations. Single nucleotide polymorphisms (SNPs) explain 90% of the genetic differences between individuals; therefore, they are most suitable for genetic evaluation and strategies that employ molecular genetics for selective breeding. SNPs found within or near a coding sequence are of particular interest because they are more likely to alter the biological function of a protein. We aimed to use SNPs to identify markers and genes associated with genetic variation in growth. RNA-Seq whole-transcriptome analysis of pooled cDNA samples from a population of rainbow trout selected for improved growth versus unselected genetic cohorts (10 fish from 1 full-sib family each) identified SNP markers associated with growth-rate. The allelic imbalances (the ratio between the allele frequencies of the fast growing sample and that of the slow growing sample) were considered at scores >5.0 as an amplification and <0.2 as loss of heterozygosity. A subset of SNPs (n = 54) were validated and evaluated for association with growth traits in 778 individuals of a three-generation parent/offspring panel representing 40 families. Twenty-two SNP markers and one mitochondrial haplotype were significantly associated with growth traits. Polymorphism of 48 of the markers was confirmed in other commercially important aquaculture stocks. Many markers were clustered into genes of metabolic energy production pathways and are suitable candidates for genetic selection. The study demonstrates that RNA-Seq at low sequence coverage of divergent populations is a fast and effective means of identifying SNPs, with allelic imbalances between phenotypes. This technique is suitable for marker

  8. Y-SNP L1034: limited genetic link between Mansi and Hungarian-speaking populations.

    PubMed

    Fehér, T; Németh, E; Vándor, A; Kornienko, I V; Csáji, L K; Pamjav, H

    2015-02-01

    Genetic studies noted that the Hungarian Y-chromosomal gene pool significantly differs from other Uralic-speaking populations. Hungarians show very limited or no presence of haplogroup N-Tat, which is frequent among other Uralic-speaking populations. We proposed that some genetic links need to be observed between the linguistically related Hungarian and Mansi populations.This is the first attempt to divide haplogroup N-Tat into subhaplogroups by testing new downstream SNP markers L708 and L1034. Sixty Northern Mansi samples were collected in Western Siberia and genotyped for Y-chromosomal haplotypes and haplogroups. We found 14 Mansi and 92 N-Tat samples from 7 populations. Comparative results showed that all N-Tat samples carried the N-L708 mutation. Some Hungarian, Sekler, and Uzbek samples were L1034 SNP positive, while all Mongolians, Buryats, Khanty, Finnish, and Roma samples yielded a negative result for this marker. Based on the above, L1034 marker seems to be a subgroup of N-Tat, which is typical for Mansi and Hungarian-speaking ethnic groups so far. Based on our time to most recent common ancestor data, the L1034 marker arose 2,500 years before present. The overall frequency of the L1034 is very low among the analyzed populations, thus it does not necessarily mean that proto-Hungarians and Mansi descend from common ancestors. It does provide, however, a limited genetic link supporting language contact. Both Hungarians and Mansi have much more complex genetic population history than the traditional tree-based linguistic model would suggest. PMID:25258186

  9. A High Density SNP Array for the Domestic Horse and Extant Perissodactyla: Utility for Association Mapping, Genetic Diversity, and Phylogeny Studies

    PubMed Central

    McCue, Molly E.; Bannasch, Danika L.; Petersen, Jessica L.; Gurr, Jessica; Bailey, Ernie; Binns, Matthew M.; Distl, Ottmar; Guérin, Gérard; Hasegawa, Telhisa; Hill, Emmeline W.; Leeb, Tosso; Lindgren, Gabriella; Penedo, M. Cecilia T.; Røed, Knut H.; Ryder, Oliver A.; Swinburne, June E.; Tozaki, Teruaki; Valberg, Stephanie J.; Vaudin, Mark; Lindblad-Toh, Kerstin

    2012-01-01

    An equine SNP genotyping array was developed and evaluated on a panel of samples representing 14 domestic horse breeds and 18 evolutionarily related species. More than 54,000 polymorphic SNPs provided an average inter-SNP spacing of ∼43 kb. The mean minor allele frequency across domestic horse breeds was 0.23, and the number of polymorphic SNPs within breeds ranged from 43,287 to 52,085. Genome-wide linkage disequilibrium (LD) in most breeds declined rapidly over the first 50–100 kb and reached background levels within 1–2 Mb. The extent of LD and the level of inbreeding were highest in the Thoroughbred and lowest in the Mongolian and Quarter Horse. Multidimensional scaling (MDS) analyses demonstrated the tight grouping of individuals within most breeds, close proximity of related breeds, and less tight grouping in admixed breeds. The close relationship between the Przewalski's Horse and the domestic horse was demonstrated by pair-wise genetic distance and MDS. Genotyping of other Perissodactyla (zebras, asses, tapirs, and rhinoceros) was variably successful, with call rates and the number of polymorphic loci varying across taxa. Parsimony analysis placed the modern horse as sister taxa to Equus przewalski. The utility of the SNP array in genome-wide association was confirmed by mapping the known recessive chestnut coat color locus (MC1R) and defining a conserved haplotype of ∼750 kb across all breeds. These results demonstrate the high quality of this SNP genotyping resource, its usefulness in diverse genome analyses of the horse, and potential use in related species. PMID:22253606

  10. Detection of copy number variation by SNP-allelotyping.

    PubMed

    Parker, Brett; Alexander, Ryan; Wu, Xingyao; Feely, Shawna; Shy, Michael; Schnetz-Boutaud, Nathalie; Li, Jun

    2015-03-01

    Charcot-Marie-Tooth disease type 1A (CMT1A) is caused by an abnormal copy number variation (CNV) with a trisomy of chromosome 17p12. The increase of the DNA-segment copy number is expected to alter the allele frequency of single nucleotide polymorphism (SNP) within the duplicated region. We tested whether SNP allele frequency determined by a Sequenom MassArray can be used to detect the CMT1A mutation. Our results revealed distinct patterns of SNP allele frequency distribution, which reliably differentiated CMT1A patients from controls. This finding suggests that this technique may serve as an alternative approach to identifying CNV in certain diseases, including CMT1A. PMID:24830919

  11. Genealogical analysis of cystic fibrosis families and chromosome 7q RFLP haplotypes in the Hutterite Brethren.

    PubMed Central

    Fujiwara, T M; Morgan, K; Schwartz, R H; Doherty, R A; Miller, S R; Klinger, K; Stanislovitis, P; Stuart, N; Watkins, P C

    1989-01-01

    In the 100-year period 1880-1980 the Hutterite population increased from about 442 to 23,000 individuals in North America. There are three endogamous subdivisions in this Caucasian genetic isolate. A total of 11 cystic fibrosis (CF) families from Canada and the United States were investigated, including at least two families from each of the three subdivisions, the Dariusleut, Lehrerleut, and Schmiedeleut. A study of RFLPs for the loci D7S8, D7S23, MET, and D7S18 (also called D7S16) in the region of the CF gene in 10 families shows considerable genetic variability. There were three different extended CF gene-region haplotypes on CF chromosomes (CF haplotypes), and there were 13 different extended CF gene-region haplotypes on normal chromosomes (normal haplotypes). The three CF haplotypes have different D7S23 and MET haplotypes. Parents who have the same CF haplotype are, on the average, more closely related than parents who have different haplotypes, but only within the same subdivision. A marriage node graph of 11 families illustrates the complexity of Hutterite genealogies. The frequency distribution of CF haplotypes in the Hutterite sample differs notably from those of larger agglomerates of family data from collaborative studies, with respect to D7S8, MET haplotypes, and D7S23 haplotypes. We propose that there were at least three CF carriers among the founders of the Hutterite population and that copies of a particular CF haplotype in current individuals are identical by descent. The alternative that one or more genetically distinguishable CF haplotypes resulted from recombination since the founding of the population is considered to be less likely. PMID:2563632

  12. Association Study Between SLC15A4 Polymorphisms and Haplotypes and Systemic Lupus Erythematosus in a Han Chinese Population

    PubMed Central

    Zhang, Mingwang; Chen, Fangru; Zhang, Dongmei

    2016-01-01

    Objective: The gene SLC15A4 (solute carrier family 15 [oligopeptide transporter], member 4) has been reported as contributing to the pathogenesis of systemic lupus erythematosus (SLE). We performed a case–control replication study to investigate further the association between single-nucleotide polymorphisms (SNPs) in the SLC15A4 gene and systemic SLE in a Han Chinese population. Methods: In Han Chinese SLE patients and healthy individuals (n = 355, 375, respectively), 18 SNPs in the SLC15A4 gene were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and TaqMan SNP genotyping assays. Analyses of allele frequencies and genotypes using codominant, dominant, and recessive models were conducted, as well as a linkage disequilibrium analysis. P values < 0.05 were considered significant. Results: Allele frequencies of five of the analyzed SNPs were significantly associated with SLE. Under a codominant model the genotype frequencies of rs3765108 AG and rs7308691 AT were significantly higher in the SLE group than the control group (p = 0.019, 0.049, respectively). Under a dominant model the rs1385374 (TT+CT) SNP carried a higher risk of SLE than (CC) (p = 0.042). One SLC15A4 haplotype (TA), which consists of 2 SNPs (rs959989 and rs983492), was associated with SLE (p = 0.024). Conclusion: Our study determined that five SNPs (rs959989, rs1385374, rs983492, rs12298615, and rs10847697) are associated with SLE. Thus, SLC15A4 may be important in the pathogenesis of SLE in Han Chinese patients. PMID:27362648

  13. PAX6 Haplotypes Are Associated with High Myopia in Han Chinese

    PubMed Central

    Jiang, Bo; Yap, Maurice K. H.; Leung, Kim Hung; Ng, Po Wah; Fung, Wai Yan; Lam, Wai Wa; Gu, Yang-shun; Yip, Shea Ping

    2011-01-01

    Background The paired box 6 (PAX6) gene is considered as a master gene for eye development. Linkage of myopia to the PAX6 region on chromosome 11p13 was shown in several studies, but the results for association between myopia and PAX6 were inconsistent so far. Methodology/Principal Findings We genotyped 16 single nucleotide polymorphisms (SNPs) in the PAX6 gene and its regulatory regions in an initial study for 300 high myopia cases and 300 controls (Group 1), and successfully replicated the positive results with another independent group of 299 high myopia cases and 299 controls (Group 2). Five SNPs were genotyped in the replication study. The spherical equivalent of subjects with high myopia was ≤−8.0 dioptres. The PLINK package was used for genetic data analysis. No association was found between each of the SNPs and high myopia. However, exhaustive sliding-window haplotype analysis highlighted an important role for rs12421026 because haplotypes containing this SNP were found to be associated with high myopia. The most significant results were given by the 4-SNP haplotype window consisting of rs2071754, rs3026393, rs1506 and rs12421026 (P = 3.54×10−10, 4.06×10−11 and 1.56×10−18 for Group 1, Group 2 and Combined Group, respectively) and the 3-SNP haplotype window composed of rs3026393, rs1506 and rs12421026 (P = 5.48×10−10, 7.93×10−12 and 6.28×10−23 for the three respective groups). The results remained significant after correction for multiple comparisons by permutations. The associated haplotyes found in a previous study were also successfully replicated in this study. Conclusions/Significance PAX6 haplotypes are associated with susceptibility to the development of high myopia in Chinese. The PAX6 locus plays a role in high myopia. PMID:21589860

  14. Introgression of a rare haplotype from Southeastern Africa to breed California blackeyes with larger seeds

    PubMed Central

    Lucas, Mitchell R.; Huynh, Bao-Lam; Roberts, Philip A.; Close, Timothy J.

    2015-01-01

    Seed size distinguishes most crops from their wild relatives and is an important quality trait for the grain legume cowpea. In order to breed cowpea varieties with larger seeds we introgressed a rare haplotype associated with large seeds at the Css-1 locus from an African buff seed type cultivar, IT82E-18 (18.5 g/100 seeds), into a blackeye seed type cultivar, CB27 (22 g/100 seed). Four recombinant inbred lines derived from these two parents were chosen for marker-assisted breeding based on SNP genotyping with a goal of stacking large seed haplotypes into a CB27 background. Foreground and background selection were performed during two cycles of backcrossing based on genome-wide SNP markers. The average seed size of introgression lines homozygous for haplotypes associated with large seeds was 28.7g/100 seed and 24.8 g/100 seed for cycles 1 and 2, respectively. One cycle 1 introgression line with desirable seed quality was selfed for two generations to make families with very large seeds (28–35 g/100 seeds). Field-based performance trials helped identify breeding lines that not only have large seeds but are also desirable in terms of yield, maturity, and plant architecture when compared to industry standards. A principal component analysis was used to explore the relationships between the parents relative to a core set of landraces and improved varieties based on high-density SNP data. The geographic distribution of haplotypes at the Css-1 locus suggest the haplotype associated with large seeds is unique to accessions collected from Southeastern Africa. Therefore this quantitative trait locus has a strong potential to develop larger seeded varieties for other growing regions which is demonstrated in this work using a California pedigree. PMID:25852699

  15. Gender-Dimorphic Impact of PXR Genotype and Haplotype on Hepatotoxicity During Antituberculosis Treatment

    PubMed Central

    Wang, Jann Yuan; Tsai, Ching Hui; Lee, Yungling Leo; Lee, Li Na; Hsu, Chia Lin; Chang, Hsiu Ching; Chen, Jong Ming; Hsu, Cheng An; Yu, Chong Jen; Yang, Pan Chyr

    2015-01-01

    Abstract Women have a higher risk of drug-induced hepatotoxicity during antituberculosis treatment (HATT) than men. We hypothesized that single nucleotide polymorphism (SNP) genotype and derived haplotype of pregnane X receptor (PXR) gene, which could regulate the expression of phase I enzyme cytochrome P450 (CYP) 3A4, had a sex-specific influence on the risk of HATT. Six SNPs of the PXR gene were sequenced. Genotypes and haplotypes of the PXR SNPs, and other potential risk factors for HATT were compared between pulmonary TB patients with and those without HATT. HATT was defined as an increase in serum transaminase level >3 times the upper limit of normal (ULN) with symptoms, or >5 times ULN without symptoms. We performed the study in a derivation and a validation cohort. Among the 355 patients with pulmonary TB in the derivation cohort, 70 (19.7%) developed HATT. Logistic regression analysis revealed the risk of HATT increased in female genotype AA at rs2461823 (OR: 6.87 [2.55–18.52]) and decreased in female genotype AA at rs7643645 (OR: 0.14 [0.02–1.02]) of PXR gene. Haplotype analysis showed that female h001101 (OR: 2.30 [1.22–4.32]) and female h000110 (OR: 2.25 [1.08–4.69]) haplotype were associated with increased HATT risk. The identified predictors were also significantly associated with female HATT risk among the 182 patients in the validation cohort. Two PXR SNP genotypes and 2 haplotypes influenced the risk of HATT only in females. The PXR SNP showed a sex-specific impact that contributed to an increased HATT risk in females.

  16. Kullback-Leibler divergence for detection of rare haplotype common disease association.

    PubMed

    Lin, Shili

    2015-11-01

    Rare haplotypes may tag rare causal variants of common diseases; hence, detection of such rare haplotypes may also contribute to our understanding of complex disease etiology. Because rare haplotypes frequently result from common single-nucleotide polymorphisms (SNPs), focusing on rare haplotypes is much more economical compared with using rare single-nucleotide variants (SNVs) from sequencing, as SNPs are available and 'free' from already amassed genome-wide studies. Further, associated haplotypes may shed light on the underlying disease causal mechanism, a feat unmatched by SNV-based collapsing methods. In recent years, data mining approaches have been adapted to detect rare haplotype association. However, as they rely on an assumed underlying disease model and require the specification of a null haplotype, results can be erroneous if such assumptions are violated. In this paper, we present a haplotype association method based on Kullback-Leibler divergence (hapKL) for case-control samples. The idea is to compare haplotype frequencies for the cases versus the controls by computing symmetrical divergence measures. An important property of such measures is that both the frequencies and logarithms of the frequencies contribute in parallel, thus balancing the contributions from rare and common, and accommodating both deleterious and protective, haplotypes. A simulation study under various scenarios shows that hapKL has well-controlled type I error rates and good power compared with existing data mining methods. Application of hapKL to age-related macular degeneration (AMD) shows a strong association of the complement factor H (CFH) gene with AMD, identifying several individual rare haplotypes with strong signals. PMID:25735482

  17. A common spinal muscular atrophy deletion mutation is present on a single founder haplotype in the US Hutterites

    PubMed Central

    Chong, Jessica X; Oktay, A Afşin; Dai, Zunyan; Swoboda, Kathryn J; Prior, Thomas W; Ober, Carole

    2011-01-01

    Spinal muscular atrophy (SMA) is an autosomal recessive (AR) neuromuscular disease that is one of the most common lethal genetic disorders in children, with carrier frequencies as high as ∼1 in 35 in US Whites. As part of our genetic studies in the Hutterites from South Dakota, we identified a large 22 Mb run of homozygosity, spanning the SMA locus in an affected child, of which 10 Mb was also homozygous in three affected Hutterites from Montana, supporting a single founder origin for the mutation. We developed a haplotype-based method for identifying carriers of the SMN1 deletion that leveraged existing genome-wide SNP genotype data for ∼1400 Hutterites. In combination with two direct PCR-based assays, we identified 176 carriers of the SMN1 deletion, one asymptomatic homozygous adult and three carriers of a de novo deletion. This corresponds to a carrier frequency of one in eight (12.5%) in the South Dakota Hutterites, representing the highest carrier frequency reported to date for SMA and for an AR disease in the Hutterite population. Lastly, we show that 26 SNPs can be used to predict SMA carrier status in the Hutterites, with 99.86% specificity and 99.71% sensitivity. PMID:21610747

  18. Use of haplotypes to estimate Mendelian sampling effects and selection limits.

    PubMed

    Cole, J B; VanRaden, P M

    2011-12-01

    Limits to selection and Mendelian sampling (MS) terms can be calculated using haplotypes by summing the individual additive effects on each chromosome. Haplotypes were imputed for 43 382 single-nucleotide polymorphisms (SNP) in 1455 Brown Swiss, 40 351 Holstein and 4064 Jersey bulls and cows using the Fortran program findhap.f90, which combines population and pedigree haplotyping methods. Lower and upper bounds of MS variance were calculated for daughter pregnancy rate (a measure of fertility), milk yield, lifetime net merit (a measure of profitability) and protein yield assuming either no or complete linkage among SNP on the same chromosome. Calculated selection limits were greater than the largest direct genomic values observed in all breeds studied. The best chromosomal genotypes generally consisted of two copies of the same haplotype even after adjustment for inbreeding. Selection of animals rather than chromosomes may result in slower progress, but limits may be the same because most chromosomes will become homozygous with either strategy. Selection on functions of MS could be used to change variances in later generations. PMID:22059578

  19. Croatian national reference Y-STR haplotype database.

    PubMed

    Mršić, Gordan; Gršković, Branka; Vrdoljak, Andro; Popović, Maja; Valpotić, Ivica; Anđelinović, Šimun; Stenzl, Vlastimil; Ehler, Edvard; Urban, Ludvik; Lacković, Gordana; Underhill, Peter; Primorac, Dragan

    2012-07-01

    A reference Y-chromosome short tandem repeat (STR) haplotype database is needed for Y-STR match interpretation as well as for national and regional characterization of populations. The aim of this study was to create a comprehensive Y-STR haplotype database of the Croatian contemporary population and to analyze substructure between the five Croatian regions. We carried out a statistical analysis of the data from previously performed genetic analyses collected during routine forensic work by the Forensic Science Centre "Ivan Vučetić". A total of 1,100 unrelated men from eastern, western, northern, southern and central Croatia were selected for the purpose of this study. Y-STRs were typed using the AmpFISTR Yfiler PCR amplification kit. Analysis of molecular variance calculated with the Y chromosome haplotype reference database online analysis tool included 16 population samples with 20,247 haplotypes. A total of 947 haplotypes were recorded, 848 of which were unique (89.5%). Haplotype diversity was 0.998, with the most frequent haplotype found in 9 of 1,100 men (0.82%). Locus diversity varied from 0.266 for DYS392 to 0.868 for DYS385. Discrimination capacity was 86.1%. Our results suggested high level of similarity among regional subpopulations within Croatia, except for mildly different southern Croatia. Relative resemblance was found with Bosnia and Herzegovina and Serbia. Whit Atheys' Haplogroup Predictor was used to estimate the frequencies of Y-chromosome haplogroups. I2a, R1a, E1b1b and R1b haplogroups were most frequent in all Croatian regions. These results are important in forensics and contribute to the population genetics and genetic background of the contemporary Croatian population. PMID:22391654

  20. PanSNPdb: The Pan-Asian SNP Genotyping Database

    PubMed Central

    Ngamphiw, Chumpol; Assawamakin, Anunchai; Xu, Shuhua; Shaw, Philip J.; Yang, Jin Ok; Ghang, Ho; Bhak, Jong; Liu, Edison; Tongsima, Sissades

    2011-01-01

    The HUGO Pan-Asian SNP consortium conducted the largest survey to date of human genetic diversity among Asians by sampling 1,719 unrelated individuals among 71 populations from China, India, Indonesia, Japan, Malaysia, the Philippines, Singapore, South Korea, Taiwan, and Thailand. We have constructed a database (PanSNPdb), which contains these data and various new analyses of them. PanSNPdb is a research resource in the analysis of the population structure of Asian peoples, including linkage disequilibrium patterns, haplotype distributions, and copy number variations. Furthermore, PanSNPdb provides an interactive comparison with other SNP and CNV databases, including HapMap3, JSNP, dbSNP and DGV and thus provides a comprehensive resource of human genetic diversity. The information is accessible via a widely accepted graphical interface used in many genetic variation databases. Unrestricted access to PanSNPdb and any associated files is available at: http://www4a.biotec.or.th/PASNP. PMID:21731755

  1. Haplotype analysis of the COMT-ARVCF gene region in Israeli anorexia nervosa family trios.

    PubMed

    Michaelovsky, Elena; Frisch, Amos; Leor, Shani; Stein, Daniel; Danziger, Yardena; Carel, Cynthia; Fennig, Silvana; Mimouni, Marc; Klauck, Sabine M; Benner, Axel; Poustka, Annemarie; Apter, Alan; Weizman, Abraham

    2005-11-01

    Anorexia nervosa (AN) is a severe and complex psychiatric disorder with a significant genetic contribution. Previously, we found an association between AN and the 158Val/Met polymorphism of the catechol-O-methyltransferase (COMT) gene in a family-based study of 51 Israeli AN trios. In the present study, we extended the original sample to include 85 family trios [66 AN restricting (AN-R) and 19 bingeing/purging (AN-BP) subtype] and performed a family-based transmission disequilibrium test (TDT) analysis for five SNPs in the COMT and two in the adjacent ARVCF gene. Association was found between AN-R and several SNPs in the COMT-ARVCF region including the 158Val/Met polymorphism. TDT analysis of 5-SNP haplotypes in AN-R trios revealed an overall statistically significant transmission disequilibrium (P < 0.001). Specifically, haplotype B [COMT-186C-408G-472G(158Val)-ARVCF-659C(220Pro)-524T(175Val)] was preferentially transmitted (P < 0.001) from parents of AN-R patients to their affected daughters, while haplotype A [COMT-186T-408C-472A(158Met)-ARVCF-659T(220Leu)-524C(175Ala)] was preferentially (P = 0.01) not transmitted. Haplotype B was associated with increased risk (RR 3.38; 0.95CI 1.98-6.43) while haplotype A exhibited a protective effect (RR 0.40; 0.95CI 0.21-0.70) for AN-R. Preferential transmission of the risk alleles and haplotypes from the parents was mostly contributed by the fathers. No significant transmission disequilibrium of alleles or haplotypes was found for AN-BP trios. The risk and protective haplotypes may carry molecular variations in the COMT gene or its vicinity that are relevant to the pathophysiology of restrictive anorexia nervosa in the Israeli-Jewish population. PMID:16118784

  2. Complementarity of Binding Motifs is a General Property of HLA-A and HLA-B Molecules and Does Not Seem to Effect HLA Haplotype Composition.

    PubMed

    Rao, Xiangyu; De Boer, Rob J; van Baarle, Debbie; Maiers, Martin; Kesmir, Can

    2013-01-01

    Different human leukocyte antigen (HLA) haplotypes (i.e., the specific combinations of HLA-A, -B, -DR alleles inherited together from one parent) are observed in different frequencies in human populations. Some haplotypes, like HLA-A1-B8, are very frequent, reaching up to 10% in the Caucasian population, while others are very rare. Numerous studies have identified associations between HLA haplotypes and diseases, and differences in haplotype frequencies can in part be explained by these associations: the stronger the association with a severe (autoimmune) disease, the lower the expected HLA haplotype frequency. The peptide repertoires of the HLA molecules composing a haplotype can also influence the frequency of a haplotype. For example, it would seem advantageous to have HLA molecules with non-overlapping binding specificities within a haplotype, as individuals expressing such an haplotype would present a diverse set of peptides from viruses and pathogenic bacteria on the cell surface. To test this hypothesis, we collect the proteome data from a set of common viruses, and estimate the total ligand repertoire of HLA class I haplotypes (HLA-A-B) using in silico predictions. We compare the size of these repertoires to the HLA haplotype frequencies reported in the National Marrow Donor Program (NMDP). We find that in most HLA-A and HLA-B pairs have fairly distinct binding motifs, and that the observed haplotypes do not contain HLA-A and -B molecules with more distinct binding motifs than random HLA-A and HLA-B pairs. In addition, the population frequency of a haplotype is not correlated to the distinctness of its HLA-A and HLA-B peptide binding motifs. These results suggest that there is a not a strong selection pressure on the haplotype level favoring haplotypes having HLA molecules with distinct binding motifs, which would result the largest possible presented peptide repertoires in the context of infectious diseases. PMID:24294213

  3. β-globin haplotypes in normal and hemoglobinopathic individuals from Reconcavo Baiano, State of Bahia, Brazil

    PubMed Central

    2010-01-01

    Five restriction site polymorphisms in the β-globin gene cluster (HincII-5‘ ε, HindIII-G γ, HindIII-A γ, HincII- ψβ1 and HincII-3‘ ψβ1) were analyzed in three populations (n = 114) from Reconcavo Baiano, State of Bahia, Brazil. The groups included two urban populations from the towns of Cachoeira and Maragojipe and one rural Afro-descendant population, known as the “quilombo community”, from Cachoeira municipality. The number of haplotypes found in the populations ranged from 10 to 13, which indicated higher diversity than in the parental populations. The haplotypes 2 (+ - - - -), 3 (- - - - +), 4 (- + - - +) and 6 (- + + - +) on the βA chromosomes were the most common, and two haplotypes, 9 (- + + + +) and 14 (+ + - - +), were found exclusively in the Maragojipe population. The other haplotypes (1, 5, 9, 11, 12, 13, 14 and 16) had lower frequencies. Restriction site analysis and the derived haplotypes indicated homogeneity among the populations. Thirty-two individuals with hemoglobinopathies (17 sickle cell disease, 12 HbSC disease and 3 HbCC disease) were also analyzed. The haplotype frequencies of these patients differed significantly from those of the general population. In the sickle cell disease subgroup, the predominant haplotypes were BEN (Benin) and CAR (Central African Republic), with frequencies of 52.9% and 32.4%, respectively. The high frequency of the BEN haplotype agreed with the historical origin of the afro-descendant population in the state of Bahia. However, this frequency differed from that of Salvador, the state capital, where the CAR and BEN haplotypes have similar frequencies, probably as a consequence of domestic slave trade and subsequent internal migrations to other regions of Brazil. PMID:21637405

  4. A new SNP panel for evaluating genetic diversity in a composite cattle breed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A custom 60K SNP panel, extracted from Bovine HD SNP chip was used to evaluate genotypic frequency changes in Braford (BF, a composite breed) when compared to progenitor breeds: Hereford (HF), Brahman (BR), and Nelore (NE). Samples from both the U. S. and Brazil were used. The new panel differentiat...

  5. Detecting structure of haplotypes and local ancestry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We present a two-layer hidden Markov model to detect the structure of haplotypes for unrelated individuals. This allows us to model two scales of linkage disequilibrium (one within a group of haplotypes and one between groups), thereby taking advantage of rich haplotype information to infer local an...

  6. Haplotype-based approach for noninvasive prenatal diagnosis of congenital adrenal hyperplasia by maternal plasma DNA sequencing.

    PubMed

    Ma, Dingyuan; Ge, Huijuan; Li, Xuchao; Jiang, Tao; Chen, Fang; Zhang, Yanyan; Hu, Ping; Chen, Shengpei; Zhang, Jingjing; Ji, Xiuqing; Xu, Xun; Jiang, Hui; Chen, Minfeng; Wang, Wei; Xu, Zhengfeng

    2014-07-10

    Prenatal diagnosis of congenital adrenal hyperplasia (CAH) is of clinical significance because in utero treatment is available to prevent virilization of an affected female fetus. However, traditional prenatal diagnosis of CAH relies on genetic testing of fetal genomic DNA obtained using amniocentesis or chorionic villus sampling, which is associated with an increased risk of miscarriage. The aim of this study was to demonstrate the feasibility of a new haplotype-based approach for the noninvasive prenatal testing of CAH due to 21-hydroxylase deficiency. Parental haplotypes were constructed using target-region sequencing data of the parents and the proband. With the assistance of the parental haplotypes, we recovered fetal haplotypes using a hidden Markov model (HMM) through maternal plasma DNA sequencing. In the genomic region around the CYP21A2 gene, the fetus inherited the paternal haplotype '0' alleles linked to the mutant CYP21A2 gene, but the maternal haplotype '1' alleles linked to the wild-type gene. The fetus was predicted to be an unaffected carrier of CAH, which was confirmed by genetic analysis of fetal genomic DNA from amniotic fluid cells. This method was further validated by comparing the inferred SNP genotypes with the direct sequencing data of fetal genomic DNA. The result showed an accuracy of 96.41% for the inferred maternal alleles and an accuracy of 97.81% for the inferred paternal alleles. The haplotype-based approach is feasible for noninvasive prenatal testing of CAH. PMID:24768736

  7. Gene polymorphisms of novel immunotolerant molecule BTLA: distribution of alleles, genotypes and haplotypes in Polish Caucasian population.

    PubMed

    Partyka, Anna; Woszczyk, Dariusz; Strzała, Tomasz; Szczepańska, Anna; Tomkiewicz, Anna; Frydecka, Irena; Karabon, Lidia

    2015-02-01

    B and T lymphocyte attenuator (BTLA) is one of the members of immunoglobulin superfamily which, like CTLA-4 and PD-1, is involved in down regulation of immune response. Despite the important role of BTLA in maintaining immune homeostasis, relatively little studies were devoted to the relationship of polymorphisms in the gene encoding BTLA with susceptibility to autoimmune disease and cancer. Moreover, all published works were done in Asian populations. BTLA gene is located on chromosome 3 in q13.2 and consists of five exons. The aim of this study was to investigate the alleles, genotypes and haplotypes frequency of selected BTLA gene polymorphisms in Caucasian population originating from Poland. For this study, the single-nucleotide polymorphisms (SNPs) were chosen on the basis of literature data. Additionally, the tag dSNP under linkage equilibrium r (2) > 0.8 and available at the National Center for Biotechnology Information (NCBI) for Caucasian population of rare alleles at a frequency greater than 5 % have been chosen using the NCBI database. The ten BTLA SNPs investigated were: rs1844089, rs2705535, rs9288952, rs9288953, rs1982809, rs2633580, rs2705511, rs2705565, rs76844316, rs16859633. For all SNPs selected on the basis of literature data the significantly different distributions of genotypes between Asian and Caucasian populations were observed. PMID:25182981

  8. CAPN1, CAST, and DGAT1 genetic effects on preweaning performance, carcass quality traits, and residual variance of tenderness in a beef cattle population selected for haplotype and allele equalization.

    PubMed

    Tait, R G; Shackelford, S D; Wheeler, T L; King, D A; Keele, J W; Casas, E; Smith, T P L; Bennett, G L

    2014-12-01

    Genetic marker effects and type of inheritance are estimated with poor precision when minor marker allele frequencies are low. A stable composite population (MARC III) was subjected to marker-assisted selection for multiple years to equalize specific marker frequencies to 1) estimate effect size and mode of inheritance for previously reported SNP on targeted beef carcass quality traits (n=254), 2) estimate pleiotropic effects of previously reported SNP on nontarget performance traits (n=542 or 254), and 3) evaluate tenderness SNP specific residual variance for LM tenderness. Three haplotypes within μ-calpain (CAPN1), a SNP in calpastatin (CAST), and a dinucleotide substitution in diacylglycerol O-acyltransferase 1 (DGAT1) were successfully selected to equalize their frequencies. Traits evaluated were birth BW, weaning BW, yearling BW, final BW, dressing percent, HCW, fat thickness, LM area, USDA marbling score, yield grade, LM slice shear force (SSF), and visible and near-infrared (VISNIR)-predicted SSF. While the CAPN1 genotype effect on SSF was not significant (P=0.12), the direction and size of CAPN1 contrasts were consistent with previous research. Effects on SSF between divergent CAPN1 haplotypes (1.153 kg) and the additive effect of CAST (0.902 kg) were large, and animals homozygous for tender alleles at both CAPN1 and CAST would have 4.11 kg lower SSF (27.5% of the mean) than animals homozygous tough for both markers. Furthermore, the interaction between CAPN1 and CAST for SSF was not significant (P=0.40). There were significant effects for DGAT1 on adjusted fat thickness (P=0.02) and VISNIR-predicted SSF (P<0.001) with additive and dominance modes of inheritance (P<0.05) for both traits. Furthermore, CAST genotype specific residual variance models fit significantly better (P<0.001) than single residual variance models for SSF, with the tougher genotypes having progressively larger residual (and hence phenotypic) variances. Therefore, risk of a tough steak

  9. Detecting disease-predisposing variants: The haplotype method

    SciTech Connect

    Valdes, A.M.; Thomson, G.

    1997-03-01

    For many HLA-associated diseases, multiple alleles - and, in some cases, multiple loci - have been suggested as the causative agents. The haplotype method for identifying disease-predisposing amino acids in a genetic region is a stratification analysis. We show that, for each haplotype combination containing all the amino acid sites involved in the disease process, the relative frequencies of amino acid variants at sites not involved in disease but in linkage disequilibrium with the disease-predisposing sites are expected to be the same in patients and controls. The haplotype method is robust to mode of inheritance and penetrance of the disease and can be used to determine unequivocally whether all amino acid sites involved in the disease have not been identified. Using a resampling technique, we developed a statistical test that takes account of the nonindependence of the sites sampled. Further, when multiple sites in the genetic region are involved in disease, the test statistic gives a closer fit to the null expectation when some - compared with none - of the true predisposing factors are included in the haplotype analysis. Although the haplotype method cannot distinguish between very highly correlated sites in one population, ethnic comparisons may help identify the true predisposing factors. The haplotype method was applied to insulin-dependent diabetes mellitus (IDDM) HLA class II DQA1-DQB1 data from Caucasian, African, and Japanese populations. Our results indicate that the combination DQA1 No. 52 (Arg predisposing) DQB1 No. 57 (Asp protective), which has been proposed as an important IDDM agent, does not include all the predisposing elements. With rheumatoid arthritis HLA class H DRB1 data, the results were consistent with the shared-epitope hypothesis. 35 refs., 2 figs., 6 tabs.

  10. Redefinition of the human kappa opioid receptor gene (OPRK1) structure and association of haplotypes with opiate addiction.

    PubMed

    Yuferov, Vadim; Fussell, David; LaForge, K Steven; Nielsen, David A; Gordon, Derek; Ho, Ann; Leal, Suzanne M; Ott, Jurg; Kreek, Mary Jeanne

    2004-12-01

    The kappa opioid receptor (KOR) plays a role in stress responsivity, opiate withdrawal and responses to cocaine. KOR activation by its endogenous ligand dynorphin A(1-17) decreases basal and drug-induced striatal levels of dopamine. The complete structure of the human KOR gene (hOPRK1) has not been previously determined. This study: (i) characterized the genomic structure of the hOPRK1 gene; (ii) identified single nucleotide polymorphisms (SNPs) in the hOPRK1 gene; and (iii) investigated possible associations of these variants with vulnerability to develop heroin addiction. Analysis of 5'-RACE cDNA clones revealed the presence of a novel exon 1 ranging in length from 167 to 251 nucleotides in the 5' 5'-untranslated region of the hOPRK1 mRNA. We found that the hOPRK1 gene has four major exons and three introns, similar to rodent OPRK1 genes. Direct sequencing of amplified DNA containing all four exons and intron 1 of the hOPRK1 gene were evaluated for polymorphisms in 291 subjects (145 former heroin addicts and 146 controls). Twelve SNPs were identified, nine novel variants and three previously reported SNPs. Using logistic regression with opioid dependence as the dependent variable, the 36G>T SNP exhibited a point-wise significant association (P = 0.016) with disease status. The number of haplotypes seen in the three ethnic groups were nine, six and five for African-Americans, Caucasians, and Hispanics, respectively, with corresponding significance levels for differences in haplotype frequencies between cases and controls of P = 0.0742, 0.1015 and 0.0041. Combining ethnicities by Fisher's method yields an empirical significance level of P = 0.0020. PMID:15608558

  11. Haplotype studies in Wilson disease

    SciTech Connect

    Thomas, G.R.; Bull, P.C.; Roberts, E.A.; Cox, D.W.; Walshe, J.M. )

    1994-01-01

    In 51 families with Wilson disease, the authors have studied DNA haplotypes of dinucleotide repeat polymorphisms (CA repeats) in the 13q14.3 region, to examine these markers for association with the Wilson disease gene (WND). In addition to a marker (D13S133) described elsewhere, the authors have developed three new highly polymorphic markers (D13S314, D13S315, and D13S316) close to the WND locus. The authors have examined the distribution of marker alleles at the loci studied and have found that D13S314, D13S133, and D13S316 each show nonrandom distribution on chromosomes carrying the WND mutation. The authors have studied haplotypes of these three markers and have found that there are highly significant differences between WND and normal haplotypes in northern European families. These findings have important implications for mutation detection and molecular diagnosis in families with Wilson disease. 25 refs., 2 figs., 5 tabs.

  12. Clarifying haplotype ambiguity of NAT2 in multi-national cohorts.

    PubMed

    Selinski, Silvia; Blaszkewicz, Meinolf; Agundez, Jose A G; Martinez, Carmen; Garcia-Martin, Elena; Hengstler, Jan G; Golka, Klaus

    2013-01-01

    N-Acetyltransferase 2 (NAT2) is the key enzyme in aromatic amine metabolism. NAT2 genotyping requires a subsequent determination of the haplotype pairs (formerly: alleles) to derive the acetylation status. The chromosomal phase of the single nucleotide polymorphisms (SNPs) is unclear for about 2/3 of the genotypes. We investigated NAT2 genotypes of 1,234 bladder cancer cases and 2,207 controls from Germany, Hungary, Pakistan and Venezuela plus 696 further German cancer cases. We reconstructed NAT2 haplotypes using PHASE v2.1.1. We analysed if the variability of the NAT2 haplotypes affected the haplotype reconstruction. Furthermore, we compared population haplotype frequencies in three Caucasian control cohorts (German, Hungarian, Spanish), in Pakistanis and Venezuelans and the impact on bladder cancer. We conclude that a common haplotype reconstruction is feasible, enhances precision and reliability. Hungarian controls showed the largest intra-ethnic variability whereas the Pakistanis showed a haplotype distribution typical for Caucasians. The main differences could be observed for the slow haplotypes *5B, *6A and *7B. The association of slow NAT2 genotypes with bladder cancer risk was most prominent in the Venezuelan study group. PMID:23277078

  13. Plastid DNA sequencing and nuclear SNP genotyping help resolve the puzzle of central American Platanus

    PubMed Central

    De Castro, Olga; Di Maio, Antonietta; Lozada García, José Armando; Piacenti, Danilo; Vázquez-Torres, Mario; De Luca, Paolo

    2013-01-01

    Background and Aims Recent research on the history of Platanus reveals that hybridization phenomena occurred in the central American species. This study has two goals: to help resolve the evolutive puzzle of central American Platanus, and to test the potential of real-time polymerase chain reaction (PCR) for detecting ancient hybridization. Methods Sequencing of a uniparental plastid DNA marker [psbA-trnH(GUG) intergenic spacer] and qualitative and quantitative single nucleotide polymorphism (SNP) genotyping of biparental nuclear ribosomal DNA (nrDNA) markers [LEAFY intron 2 (LFY-i2) and internal transcribed spacer 2 (ITS2)] were used. Key Results Based on the SNP genotyping results, several Platanus accessions show the presence of hybridization/introgression, including some accessions of P. rzedowskii and of P. mexicana var. interior and one of P. mexicana var. mexicana from Oaxaca (= P. oaxacana). Based on haplotype analyses of the psbA-trnH spacer, five haplotypes were detected. The most common of these is present in taxa belonging to P. orientalis, P. racemosa sensu lato, some accessions of P. occidentalis sensu stricto (s.s.) from Texas, P. occidentalis var. palmeri, P. mexicana s.s. and P. rzedowskii. This is highly relevant to genetic relationships with the haplotypes present in P. occidentalis s.s. and P. mexicana var. interior. Conclusions Hybridization and introgression events between lineages ancestral to modern central and eastern North American Platanus species occurred. Plastid haplotypes and qualitative and quantitative SNP genotyping provide information critical for understanding the complex history of Mexican Platanus. Compared with the usual molecular techniques of sub-cloning, sequencing and genotyping, real-time PCR assay is a quick and sensitive technique for analysing complex evolutionary patterns. PMID:23798602

  14. Inferring Selection Intensity and Allele Age from Multilocus Haplotype Structure

    PubMed Central

    Chen, Hua; Slatkin, Montgomery

    2013-01-01

    It is a challenging task to infer selection intensity and allele age from population genetic data. Here we present a method that can efficiently estimate selection intensity and allele age from the multilocus haplotype structure in the vicinity of a segregating mutant under positive selection. We use a structured-coalescent approach to model the effect of directional selection on the gene genealogies of neutral markers linked to the selected mutant. The frequency trajectory of the selected allele follows the Wright-Fisher model. Given the position of the selected mutant, we propose a simplified multilocus haplotype model that can efficiently model the dynamics of the ancestral haplotypes under the joint influence of selection and recombination. This model approximates the ancestral genealogies of the sample, which reduces the number of states from an exponential function of the number of single-nucleotide polymorphism loci to a quadratic function. That allows parameter inference from data covering DNA regions as large as several hundred kilo-bases. Importance sampling algorithms are adopted to evaluate the probability of a sample by exploring the space of both allele frequency trajectories of the selected mutation and gene genealogies of the linked sites. We demonstrate by simulation that the method can accurately estimate selection intensity for moderate and strong positive selection. We apply the method to a data set of the G6PD gene in an African population and obtain an estimate of 0.0456 (95% confidence interval 0.0144−0.0769) for the selection intensity. The proposed method is novel in jointly modeling the multilocus haplotype pattern caused by recombination and mutation, allowing the analysis of haplotype data in recombining regions. Moreover, the method is applicable to data from populations under exponential growth and a variety of other demographic histories. PMID:23797107

  15. Practical interpretation of CYP2D6 haplotypes: Comparison and integration of automated and expert calling.

    PubMed

    Ruaño, Gualberto; Kocherla, Mohan; Graydon, James S; Holford, Theodore R; Makowski, Gregory S; Goethe, John W

    2016-05-01

    We describe a population genetic approach to compare samples interpreted with expert calling (EC) versus automated calling (AC) for CYP2D6 haplotyping. The analysis represents 4812 haplotype calls based on signal data generated by the Luminex xMap analyzers from 2406 patients referred to a high-complexity molecular diagnostics laboratory for CYP450 testing. DNA was extracted from buccal swabs. We compared the results of expert calls (EC) and automated calls (AC) with regard to haplotype number and frequency. The ratio of EC to AC was 1:3. Haplotype frequencies from EC and AC samples were convergent across haplotypes, and their distribution was not statistically different between the groups. Most duplications required EC, as only expansions with homozygous or hemizygous haplotypes could be automatedly called. High-complexity laboratories can offer equivalent interpretation to automated calling for non-expanded CYP2D6 loci, and superior interpretation for duplications. We have validated scientific expert calling specified by scoring rules as standard operating procedure integrated with an automated calling algorithm. The integration of EC with AC is a practical strategy for CYP2D6 clinical haplotyping. PMID:26908082

  16. A TNF region haplotype offers protection from typhoid fever in Vietnamese patients

    PubMed Central

    2009-01-01

    The genomic region surrounding the TNF locus on human chromosome 6 has previously been associated with typhoid fever in Vietnam. We used a haplotypic approach to understand this association further. Eighty single nucleotide polymorphisms (SNPs) spanning a 150 kb region were genotyped in 95 Vietnamese individuals (typhoid case/mother/father trios). A subset of data from 33 SNPs with a minor allele frequency of >4.3% was used to construct haplotypes. Fifteen SNPs, which tagged the 42 constructed haplotypes were selected. The haplotype tagging SNPs (T1-T15) were genotyped in 380 confirmed typhoid cases and 380 Vietnamese ethnically matched controls. Allelic frequencies of seven SNPs (T1, T2, T3, T5, T6, T7, T8) were significantly different between typhoid cases and controls. Logistic regression results support the hypothesis that there is just one signal associated with disease at this locus. Haplotype-based analysis of the tag SNPs provided positive evidence of association with typhoid (posterior probability 0.821). The analysis highlighted a low-risk cluster of haplotypes that each carry the minor allele of T1 or T7, but not both, and otherwise carry the combination of alleles *12122*1111 at T1-T11, further supporting the one associated signal hypothesis. Finally, individuals that carry the typhoid fever protective haplotype *12122*1111 also produce a relatively low TNF-α response to LPS. PMID:17503085

  17. Genotype-phenotype correlations in 5-fluorouracil metabolism: a candidate DPYD haplotype to improve toxicity prediction.

    PubMed

    Gentile, G; Botticelli, A; Lionetto, L; Mazzuca, F; Simmaco, M; Marchetti, P; Borro, M

    2016-08-01

    5-Fluorouracil is among the most widely used anticancer drug, but a fraction of treated patients develop severe toxicity, with potentially lethal injuries. The predictive power of the available pretreatment assays, used to identify patients at risk of severe toxicity, needs improvements. This study aimed to correlate a phenotypic marker of 5-fluorouracil metabolism (the individual degradation rate of 5-fluorouracil-5-FUDR) with 15 functional polymorphisms in the dihydropyrimidine dehydrogenase gene (DPYD). Single SNP (single-nucleotide polymorphism) analysis revealed that the SNPs rs1801160, rs1801265, rs2297595 and rs3918290 (splice site variant IVS14+1G>A) were significantly associated with a decreased value of 5-FUDR, and the rs3918290 causing the larger decrease. Multi-SNP analysis showed that a three-SNP haplotype (Hap7) involving rs1801160, rs1801265 and rs2297595 causes a marked decrease in 5-FUDR, comparable to that caused by the splice site variant rs3918290, which is the main pharmacogenetic marker associated with severe fluorouracil toxicity. The similar effect played by Hap7 and by the splice site variant rs3918290 upon individual 5-FUDR suggests that Hap7 could also represent a similar determinant of fluorouracil toxicity. Haplotype assessment could improve the predictive value of DPYD genetic markers aimed at the pre-emptive identification of patients at risk of severe 5-fluorouracil toxicity.The Pharmacogenomics Journal advance online publication, 28 July 2015; doi:10.1038/tpj.2015.56. PMID:26216193

  18. Ashkenazi levites' "Y modal haplotype" (LMH)-- an artificially created phenomenon?

    PubMed

    Zoossmann-Diskin, A

    2006-01-01

    The article on the Y chromosomes of Ashkenazi Levites (Behar et al., 2003. Am. J. Hum. Genet. 73, 768-779) is the fourth in a series on the Y chromosomes of the three Jewish male castes: Cohanim (priests), Levites (priests' helpers) and Israelites (lay people). It became apparent that there is a problem with omission of samples when the second article "Origins of Old Testament priests" (Thomas et al., 1998. Nature 394, 138-140) was published. In the fourth article a remarkable 55% of the Ashkenazi Levite samples from the earlier 1998 study are not included. This causes the "Levite modal haplotype" to double its frequency from 21% of the Ashkenazi Levite sample in 1998 to 42% of the Ashkenazi Levite sample in 2003. The authors offer three main explanations: (1) The studies are independent using different sample sets.(2) Typing errors and poor quality exclude samples from future studies.(3) Correction of typing errors means that some samples are classified under different haplotypes. The explanations offered to the problem of omitting samples from subsequent studies after their haplotypes or partial haplotypes are known, are not convincing. Consequently their sample sets cannot be considered random and non-biased. At the least, these laboratories have bad practices of sample handling and many typing errors, which are enough to invalidate their studies. PMID:16427053

  19. Accuracy of direct genomic values in Holstein bulls and cows using subsets of SNP markers

    PubMed Central

    2010-01-01

    Background At the current price, the use of high-density single nucleotide polymorphisms (SNP) genotyping assays in genomic selection of dairy cattle is limited to applications involving elite sires and dams. The objective of this study was to evaluate the use of low-density assays to predict direct genomic value (DGV) on five milk production traits, an overall conformation trait, a survival index, and two profit index traits (APR, ASI). Methods Dense SNP genotypes were available for 42,576 SNP for 2,114 Holstein bulls and 510 cows. A subset of 1,847 bulls born between 1955 and 2004 was used as a training set to fit models with various sets of pre-selected SNP. A group of 297 bulls born between 2001 and 2004 and all cows born between 1992 and 2004 were used to evaluate the accuracy of DGV prediction. Ridge regression (RR) and partial least squares regression (PLSR) were used to derive prediction equations and to rank SNP based on the absolute value of the regression coefficients. Four alternative strategies were applied to select subset of SNP, namely: subsets of the highest ranked SNP for each individual trait, or a single subset of evenly spaced SNP, where SNP were selected based on their rank for ASI, APR or minor allele frequency within intervals of approximately equal length. Results RR and PLSR performed very similarly to predict DGV, with PLSR performing better for low-density assays and RR for higher-density SNP sets. When using all SNP, DGV predictions for production traits, which have a higher heritability, were more accurate (0.52-0.64) than for survival (0.19-0.20), which has a low heritability. The gain in accuracy using subsets that included the highest ranked SNP for each trait was marginal (5-6%) over a common set of evenly spaced SNP when at least 3,000 SNP were used. Subsets containing 3,000 SNP provided more than 90% of the accuracy that could be achieved with a high-density assay for cows, and 80% of the high-density assay for young bulls

  20. Contrasting signals of positive selection in genes involved in human skin-color variation from tests based on SNP scans and resequencing

    PubMed Central

    2011-01-01

    Background Numerous genome-wide scans conducted by genotyping previously ascertained single-nucleotide polymorphisms (SNPs) have provided candidate signatures for positive selection in various regions of the human genome, including in genes involved in pigmentation traits. However, it is unclear how well the signatures discovered by such haplotype-based test statistics can be reproduced in tests based on full resequencing data. Four genes (oculocutaneous albinism II (OCA2), tyrosinase-related protein 1 (TYRP1), dopachrome tautomerase (DCT), and KIT ligand (KITLG)) implicated in human skin-color variation, have shown evidence for positive selection in Europeans and East Asians in previous SNP-scan data. In the current study, we resequenced 4.7 to 6.7 kb of DNA from each of these genes in Africans, Europeans, East Asians, and South Asians. Results Applying all commonly used neutrality-test statistics for allele frequency distribution to the newly generated sequence data provided conflicting results regarding evidence for positive selection. Previous haplotype-based findings could not be clearly confirmed. Although some tests were marginally significant for some populations and genes, none of them were significant after multiple-testing correction. Combined P values for each gene-population pair did not improve these results. Application of Approximate Bayesian Computation Markov chain Monte Carlo based to these sequence data using a simple forward simulator revealed broad posterior distributions of the selective parameters for all four genes, providing no support for positive selection. However, when we applied this approach to published sequence data on SLC45A2, another human pigmentation candidate gene, we could readily confirm evidence for positive selection, as previously detected with sequence-based and some haplotype-based tests. Conclusions Overall, our data indicate that even genes that are strong biological candidates for positive selection and show

  1. A 48 SNP set for grapevine cultivar identification

    PubMed Central

    2011-01-01

    Background Rapid and consistent genotyping is an important requirement for cultivar identification in many crop species. Among them grapevine cultivars have been the subject of multiple studies given the large number of synonyms and homonyms generated during many centuries of vegetative multiplication and exchange. Simple sequence repeat (SSR) markers have been preferred until now because of their high level of polymorphism, their codominant nature and their high profile repeatability. However, the rapid application of partial or complete genome sequencing approaches is identifying thousands of single nucleotide polymorphisms (SNP) that can be very useful for such purposes. Although SNP markers are bi-allelic, and therefore not as polymorphic as microsatellites, the high number of loci that can be multiplexed and the possibilities of automation as well as their highly repeatable results under any analytical procedure make them the future markers of choice for any type of genetic identification. Results We analyzed over 300 SNP in the genome of grapevine using a re-sequencing strategy in a selection of 11 genotypes. Among the identified polymorphisms, we selected 48 SNP spread across all grapevine chromosomes with allele frequencies balanced enough as to provide sufficient information content for genetic identification in grapevine allowing for good genotyping success rate. Marker stability was tested in repeated analyses of a selected group of cultivars obtained worldwide to demonstrate their usefulness in genetic identification. Conclusions We have selected a set of 48 stable SNP markers with a high discrimination power and a uniform genome distribution (2-3 markers/chromosome), which is proposed as a standard set for grapevine (Vitis vinifera L.) genotyping. Any previous problems derived from microsatellite allele confusion between labs or the need to run reference cultivars to identify allele sizes disappear using this type of marker. Furthermore, because SNP

  2. Genome-wide association studies using haplotypes and individual SNPs in Simmental cattle.

    PubMed

    Wu, Yang; Fan, Huizhong; Wang, Yanhui; Zhang, Lupei; Gao, Xue; Chen, Yan; Li, Junya; Ren, HongYan; Gao, Huijiang

    2014-01-01

    Recent advances in high-throughput genotyping technologies have provided the opportunity to map genes using associations between complex traits and markers. Genome-wide association studies (GWAS) based on either a single marker or haplotype have identified genetic variants and underlying genetic mechanisms of quantitative traits. Prompted by the achievements of studies examining economic traits in cattle and to verify the consistency of these two methods using real data, the current study was conducted to construct the haplotype structure in the bovine genome and to detect relevant genes genuinely affecting a carcass trait and a meat quality trait. Using the Illumina BovineHD BeadChip, 942 young bulls with genotyping data were introduced as a reference population to identify the genes in the beef cattle genome significantly associated with foreshank weight and triglyceride levels. In total, 92,553 haplotype blocks were detected in the genome. The regions of high linkage disequilibrium extended up to approximately 200 kb, and the size of haplotype blocks ranged from 22 bp to 199,266 bp. Additionally, the individual SNP analysis and the haplotype-based analysis detected similar regions and common SNPs for these two representative traits. A total of 12 and 7 SNPs in the bovine genome were significantly associated with foreshank weight and triglyceride levels, respectively. By comparison, 4 and 5 haplotype blocks containing the majority of significant SNPs were strongly associated with foreshank weight and triglyceride levels, respectively. In addition, 36 SNPs with high linkage disequilibrium were detected in the GNAQ gene, a potential hotspot that may play a crucial role for regulating carcass trait components. PMID:25330174

  3. Genome-Wide Association Studies Using Haplotypes and Individual SNPs in Simmental Cattle

    PubMed Central

    Wu, Yang; Fan, Huizhong; Wang, Yanhui; Zhang, Lupei; Gao, Xue; Chen, Yan; Li, Junya; Ren, HongYan; Gao, Huijiang

    2014-01-01

    Recent advances in high-throughput genotyping technologies have provided the opportunity to map genes using associations between complex traits and markers. Genome-wide association studies (GWAS) based on either a single marker or haplotype have identified genetic variants and underlying genetic mechanisms of quantitative traits. Prompted by the achievements of studies examining economic traits in cattle and to verify the consistency of these two methods using real data, the current study was conducted to construct the haplotype structure in the bovine genome and to detect relevant genes genuinely affecting a carcass trait and a meat quality trait. Using the Illumina BovineHD BeadChip, 942 young bulls with genotyping data were introduced as a reference population to identify the genes in the beef cattle genome significantly associated with foreshank weight and triglyceride levels. In total, 92,553 haplotype blocks were detected in the genome. The regions of high linkage disequilibrium extended up to approximately 200 kb, and the size of haplotype blocks ranged from 22 bp to 199,266 bp. Additionally, the individual SNP analysis and the haplotype-based analysis detected similar regions and common SNPs for these two representative traits. A total of 12 and 7 SNPs in the bovine genome were significantly associated with foreshank weight and triglyceride levels, respectively. By comparison, 4 and 5 haplotype blocks containing the majority of significant SNPs were strongly associated with foreshank weight and triglyceride levels, respectively. In addition, 36 SNPs with high linkage disequilibrium were detected in the GNAQ gene, a potential hotspot that may play a crucial role for regulating carcass trait components. PMID:25330174

  4. A Genomic Portrait of Haplotype Diversity and Signatures of Selection in Indigenous Southern African Populations

    PubMed Central

    Chimusa, Emile R.; Meintjies, Ayton; Tchanga, Milaine; Mulder, Nicola; Seoighe, Cathal; Soodyall, Himla; Ramesar, Rajkumar

    2015-01-01

    We report a study of genome-wide, dense SNP (∼900K) and copy number polymorphism data of indigenous southern Africans. We demonstrate the genetic contribution to southern and eastern African populations, which involved admixture between indigenous San, Niger-Congo-speaking and populations of Eurasian ancestry. This finding illustrates the need to account for stratification in genome-wide association studies, and that admixture mapping would likely be a successful approach in these populations. We developed a strategy to detect the signature of selection prior to and following putative admixture events. Several genomic regions show an unusual excess of Niger-Kordofanian, and unusual deficiency of both San and Eurasian ancestry, which were considered the footprints of selection after population admixture. Several SNPs with strong allele frequency differences were observed predominantly between the admixed indigenous southern African populations, and their ancestral Eurasian populations. Interestingly, many candidate genes, which were identified within the genomic regions showing signals for selection, were associated with southern African-specific high-risk, mostly communicable diseases, such as malaria, influenza, tuberculosis, and human immunodeficiency virus/AIDs. This observation suggests a potentially important role that these genes might have played in adapting to the environment. Additionally, our analyses of haplotype structure, linkage disequilibrium, recombination, copy number variation and genome-wide admixture highlight, and support the unique position of San relative to both African and non-African populations. This study contributes to a better understanding of population ancestry and selection in south-eastern African populations; and the data and results obtained will support research into the genetic contributions to infectious as well as non-communicable diseases in the region. PMID:25811879

  5. Optimal Design of Low-Density SNP Arrays for Genomic Prediction: Algorithm and Applications.

    PubMed

    Wu, Xiao-Lin; Xu, Jiaqi; Feng, Guofei; Wiggans, George R; Taylor, Jeremy F; He, Jun; Qian, Changsong; Qiu, Jiansheng; Simpson, Barry; Walker, Jeremy; Bauck, Stewart

    2016-01-01

    Low-density (LD) single nucleotide polymorphism (SNP) arrays provide a cost-effective solution for genomic prediction and selection, but algorithms and computational tools are needed for the optimal design of LD SNP chips. A multiple-objective, local optimization (MOLO) algorithm was developed for design of optimal LD SNP chips that can be imputed accurately to medium-density (MD) or high-density (HD) SNP genotypes for genomic prediction. The objective function facilitates maximization of non-gap map length and system information for the SNP chip, and the latter is computed either as locus-averaged (LASE) or haplotype-averaged Shannon entropy (HASE) and adjusted for uniformity of the SNP distribution. HASE performed better than LASE with ≤1,000 SNPs, but required considerably more computing time. Nevertheless, the differences diminished when >5,000 SNPs were selected. Optimization was accomplished conditionally on the presence of SNPs that were obligated to each chromosome. The frame location of SNPs on a chip can be either uniform (evenly spaced) or non-uniform. For the latter design, a tunable empirical Beta distribution was used to guide location distribution of frame SNPs such that both ends of each chromosome were enriched with SNPs. The SNP distribution on each chromosome was finalized through the objective function that was locally and empirically maximized. This MOLO algorithm was capable of selecting a set of approximately evenly-spaced and highly-informative SNPs, which in turn led to increased imputation accuracy compared with selection solely of evenly-spaced SNPs. Imputation accuracy increased with LD chip size, and imputation error rate was extremely low for chips with ≥3,000 SNPs. Assuming that genotyping or imputation error occurs at random, imputation error rate can be viewed as the upper limit for genomic prediction error. Our results show that about 25% of imputation error rate was propagated to genomic prediction in an Angus population. The

  6. The effect of MAPT haplotype on neocortical Lewy body pathology in Parkinson disease.

    PubMed

    Robakis, Daphne; Cortes, Etty; Clark, Lorraine N; Vonsattel, Jean Paul G; Virmani, Tuhin; Alcalay, Roy N; Crary, John F; Levy, Oren A

    2016-06-01

    The H1 haplotype of the microtubule-associated protein tau gene (MAPT) is associated with an increased risk of Parkinson disease (PD) compared with the H2 haplotype, but its effect on Lewy body (LB) formation is unclear. In this study, we compared the MAPT haplotype frequency between pathologically confirmed PD patients (n = 71) and controls (n = 52). We analyzed Braak LB stage, Braak neurofibrillary tangle (NFT) stage, and CERAD amyloid score by haplotype. We further tested the association between MAPT haplotype and semi-quantitative counts of LBs, NFTs, and neuritic plaques (NPs) in multiple neocortical regions. Consistent with previous reports, PD cases had an increased likelihood of carrying an H1/H1 genotype compared to controls (OR = 5.72, 95 % CI 1.80-18.21, p = 0.003). Braak LB, Braak NFT and CERAD scores did not differ by haplotype. However, H1/H1 carriers had higher LB counts in parietal cortex (p = 0.02) and in overall neocortical LBs (p = 0.03) compared to non-H1/H1 cases. Our analyses suggest that PD patients homozygous for the H1 haplotype have a higher burden of neocortical LB pathology. PMID:27098667

  7. Y chromosome probe p49a detects complex PvuII haplotypes and many new TaqI haplotypes in southern African populations.

    PubMed Central

    Spurdle, A; Jenkins, T

    1992-01-01

    Y-specific 49a/TaqI haplotypes were determined for 831 individuals drawn from 21 different southern African populations. A total of 31 new haplotypes were observed, some of which contained new alleles or allelic variants. Duplication, in addition to CpG mutation, is implicated in the generation of certain allelic variants. Cluster analysis of genetic distances between the populations, calculated using the 49a/TaqI haplotype frequencies, revealed a basic split between African and non-African populations. Hybrid groups cluster with the caucasoid groups, indicating that male gene flow has occurred from the latter into the former. Clustering of the negroid and Khoisan groups is not what might have been expected from the known linguistic affinities. It is suggested that the 49a/TaqI haplotype analysis of these populations is not sufficiently sensitive to distinguish between many of the populations. The Y-specific 49a/PvuII polymorphism was studied in 127 individuals from southern African populations, and 17 polymorphic fragments ranging in size from 3.6 kb to greater than 48 kb were identified. A total of 53 PvuII haplotypes were observed, corresponding to only 30 TaqI haplotypes. There appears to be poor correlation between the two polymorphisms. Images Figure 2 Figure 4 PMID:1729883

  8. Association between ABCB1 polymorphisms and haplotypes and Alzheimer's disease: a meta-analysis.

    PubMed

    Zhong, Xin; Liu, Ming-Yan; Sun, Xiao-Hong; Wei, Min-Jie

    2016-01-01

    Although several epidemiological studies have investigated the association between ATP-binding cassette subfamily B member 1 (ABCB1) gene polymorphisms and Alzheimer's disease (AD) susceptibility, controversial results exist. Here, we performed a meta-analysis to assess whether ABCB1 polymorphisms 3435C > T (rs1045642), 2677G > T/A (rs2032582), 1236C > T (rs1128503) and haplotypes were associated with AD risk. Nine independent publications were included and analyzed. Crude odds ratio (OR) and 95% confidence interval (CI) were applied to investigate the strength of the association. Sensitivity analysis was conducted to measure the robustness of our analysis. A funnel plot and trim and fill method were used to test and adjust for publication bias. The results showed a significant association between the 3435C > T single nucleotide polymorphism (SNP) and AD susceptibility (CT vs. CC: OR = 1.24, 95% CI = 1.06-1.45, P = 0.01; CT + TT vs. CC: OR = 1.21, 95% CI = 1.04-1.41, P = 0.01) in the total population, as well as in Caucasian subgroup. The 2677G > T/A SNP was related to a decreased AD risk in Caucasian subgroup (TT + TA + AA vs. GT + GA + GG: OR = 0.68, 95% CI = 0.47-0.98, P = 0.04). Moreover, the ABCB1 haplotype analysis showed that the 1236T/2677T/3435C haplotype was associated with a higher risk of AD (OR = 1.99, 95% CI = 1.24-3.18, P = 0.00). Our results suggest that the ABCB1 3435C > T SNP, the 2677G > T/A SNP and 1236T/2677T/3435C haplotype are significantly associated with AD susceptibility. PMID:27600024

  9. Association between ABCB1 polymorphisms and haplotypes and Alzheimer’s disease: a meta-analysis

    PubMed Central

    Zhong, Xin; Liu, Ming-Yan; Sun, Xiao-Hong; Wei, Min-Jie

    2016-01-01

    Although several epidemiological studies have investigated the association between ATP-binding cassette subfamily B member 1 (ABCB1) gene polymorphisms and Alzheimer’s disease (AD) susceptibility, controversial results exist. Here, we performed a meta-analysis to assess whether ABCB1 polymorphisms 3435C > T (rs1045642), 2677G > T/A (rs2032582), 1236C > T (rs1128503) and haplotypes were associated with AD risk. Nine independent publications were included and analyzed. Crude odds ratio (OR) and 95% confidence interval (CI) were applied to investigate the strength of the association. Sensitivity analysis was conducted to measure the robustness of our analysis. A funnel plot and trim and fill method were used to test and adjust for publication bias. The results showed a significant association between the 3435C > T single nucleotide polymorphism (SNP) and AD susceptibility (CT vs. CC: OR = 1.24, 95% CI = 1.06–1.45, P = 0.01; CT + TT vs. CC: OR = 1.21, 95% CI = 1.04–1.41, P = 0.01) in the total population, as well as in Caucasian subgroup. The 2677G > T/A SNP was related to a decreased AD risk in Caucasian subgroup (TT + TA + AA vs. GT + GA + GG: OR = 0.68, 95% CI = 0.47–0.98, P = 0.04). Moreover, the ABCB1 haplotype analysis showed that the 1236T/2677T/3435C haplotype was associated with a higher risk of AD (OR = 1.99, 95% CI = 1.24–3.18, P = 0.00). Our results suggest that the ABCB1 3435C > T SNP, the 2677G > T/A SNP and 1236T/2677T/3435C haplotype are significantly associated with AD susceptibility. PMID:27600024

  10. Major Soybean Maturity Gene Haplotypes Revealed by SNPViz Analysis of 72 Sequenced Soybean Genomes

    PubMed Central

    Langewisch, Tiffany; Zhang, Hongxin; Vincent, Ryan; Joshi, Trupti; Xu, Dong; Bilyeu, Kristin

    2014-01-01

    In this Genomics Era, vast amounts of next-generation sequencing data have become publicly available for multiple genomes across hundreds of species. Analyses of these large-scale datasets can become cumbersome, especially when comparing nucleotide polymorphisms across many samples within a dataset and among different datasets or organisms. To facilitate the exploration of allelic variation and diversity, we have developed and deployed an in-house computer software to categorize and visualize these haplotypes. The SNPViz software enables users to analyze region-specific haplotypes from single nucleotide polymorphism (SNP) datasets for different sequenced genomes. The examination of allelic variation and diversity of important soybean [Glycine max (L.) Merr.] flowering time and maturity genes may provide additional insight into flowering time regulation and enhance researchers' ability to target soybean breeding for particular environments. For this study, we utilized two available soybean genomic datasets for a total of 72 soybean genotypes encompassing cultivars, landraces, and the wild species Glycine soja. The major soybean maturity genes E1, E2, E3, and E4 along with the Dt1 gene for plant growth architecture were analyzed in an effort to determine the number of major haplotypes for each gene, to evaluate the consistency of the haplotypes with characterized variant alleles, and to identify evidence of artificial selection. The results indicated classification of a small number of predominant haplogroups for each gene and important insights into possible allelic diversity for each gene within the context of known causative mutations. The software has both a stand-alone and web-based version and can be used to analyze other genes, examine additional soybean datasets, and view similar genome sequence and SNP datasets from other species. PMID:24727730

  11. Computing the minimum recombinant haplotype configuration from incomplete genotype data on a pedigree by integer linear programming.

    PubMed

    Li, Jing; Jiang, Tao

    2005-01-01

    We study the problem of reconstructing haplotype configurations from genotypes on pedigree data with missing alleles under the Mendelian law of inheritance and the minimum-recombination principle, which is important for the construction of haplotype maps and genetic linkage/association analyses. Our previous results show that the problem of finding a minimum-recombinant haplotype configuration (MRHC) is in general NP-hard. This paper presents an effective integer linear programming (ILP) formulation of the MRHC problem with missing data and a branch-and-bound strategy that utilizes a partial order relationship and some other special relationships among variables to decide the branching order. Nontrivial lower and upper bounds on the optimal number of recombinants are introduced at each branching node to effectively prune the search tree. When multiple solutions exist, a best haplotype configuration is selected based on a maximum likelihood approach. The paper also shows for the first time how to incorporate marker interval distance into a rule-based haplotyping algorithm. Our results on simulated data show that the algorithm could recover haplotypes with 50 loci from a pedigree of size 29 in seconds on a Pentium IV computer. Its accuracy is more than 99.8% for data with no missing alleles and 98.3% for data with 20% missing alleles in terms of correctly recovered phase information at each marker locus. A comparison with a statistical approach SimWalk2 on simulated data shows that the ILP algorithm runs much faster than SimWalk2 and reports better or comparable haplotypes on average than the first and second runs of SimWalk2. As an application of the algorithm to real data, we present some test results on reconstructing haplotypes from a genome-scale SNP dataset consisting of 12 pedigrees that have 0.8% to 14.5% missing alleles. PMID:16108713

  12. SNP-SNP interactions in breast cancer susceptibility

    PubMed Central

    Onay, Venüs Ümmiye; Briollais, Laurent; Knight, Julia A; Shi, Ellen; Wang, Yuanyuan; Wells, Sean; Li, Hong; Rajendram, Isaac; Andrulis, Irene L; Ozcelik, Hilmi

    2006-01-01

    Background Breast cancer predisposition genes identified to date (e.g., BRCA1 and BRCA2) are responsible for less than 5% of all breast cancer cases. Many studies have shown that the cancer risks associated with individual commonly occurring single nucleotide polymorphisms (SNPs) are incremental. However, polygenic models suggest that multiple commonly occurring low to modestly penetrant SNPs of cancer related genes might have a greater effect on a disease when considered in combination. Methods In an attempt to identify the breast cancer risk conferred by SNP interactions, we have studied 19 SNPs from genes involved in major cancer related pathways. All SNPs were genotyped by TaqMan 5'nuclease assay. The association between the case-control status and each individual SNP, measured by the odds ratio and its corresponding 95% confidence interval, was estimated using unconditional logistic regression models. At the second stage, two-way interactions were investigated using multivariate logistic models. The robustness of the interactions, which were observed among SNPs with stronger functional evidence, was assessed using a bootstrap approach, and correction for multiple testing based on the false discovery rate (FDR) principle. Results None of these SNPs contributed to breast cancer risk individually. However, we have demonstrated evidence for gene-gene (SNP-SNP) interaction among these SNPs, which were associated with increased breast cancer risk. Our study suggests cross talk between the SNPs of the DNA repair and immune system (XPD-[Lys751Gln] and IL10-[G(-1082)A]), cell cycle and estrogen metabolism (CCND1-[Pro241Pro] and COMT-[Met108/158Val]), cell cycle and DNA repair (BARD1-[Pro24Ser] and XPD-[Lys751Gln]), and within carcinogen metabolism (GSTP1-[Ile105Val] and COMT-[Met108/158Val]) pathways. Conclusion The importance of these pathways and their communication in breast cancer predisposition has been emphasized previously, but their biological interactions

  13. Filling in missing genotypes using haplotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unknown genotypes can be made known (imputed) from observed genotypes at the same or nearby loci of relatives using pedigree haplotyping, or from matching allele patterns (regardless of pedigree) using population haplotyping. Fortran program findhap.f90 was designed to combine population and pedigre...

  14. Influence of promoter/enhancer region haplotypes on MGMT transcriptional regulation: a potential biomarker for human sensitivity to alkylating agents

    PubMed Central

    Abdel-Rahman, Sherif Z.

    2014-01-01

    The O 6-methylguanine-DNA methyltransferase gene (MGMT) encodes the direct reversal DNA repair protein that removes alkyl adducts from the O 6 position of guanine. Several single-nucleotide polymorphisms (SNPs) exist in the MGMT promoter/enhancer (P/E) region. However, the haplotype structure encompassing these SNPs and their functional/biological significance are currently unknown. We hypothesized that MGMT P/E haplotypes, rather than individual SNPs, alter MGMT transcription and can thus alter human sensitivity to alkylating agents. To identify the haplotype structure encompassing the MGMT P/E region SNPs, we sequenced 104 DNA samples from healthy individuals and inferred the haplotypes using the data generated. We identified eight SNPs in this region, namely T7C (rs180989103), T135G (rs1711646), G290A (rs61859810), C485A (rs1625649), C575A (rs113813075), G666A (rs34180180), C777A (rs34138162) and C1099T (rs16906252). Phylogenetics and Sequence Evolution analysis predicted 21 potential haplotypes that encompass these SNPs ranging in frequencies from 0.000048 to 0.39. Of these, 10 were identified in our study population as 20 paired haplotype combinations. To determine the functional significance of these haplotypes, luciferase reporter constructs representing these haplotypes were transfected into glioblastoma cells and their effect on MGMT promoter activity was determined. Compared with the most common (reference) haplotype 1, seven haplotypes significantly upregulated MGMT promoter activity (18–119% increase; P < 0.05), six significantly downregulated MGMT promoter activity (29–97% decrease; P < 0.05) and one haplotype had no effect. Mechanistic studies conducted support the conclusion that MGMT P/E haplotypes, rather than individual SNPs, differentially regulate MGMT transcription and could thus play a significant role in human sensitivity to environmental and therapeutic alkylating agents. PMID:24163400

  15. Interactions between SNP alleles at multiple loci contribute to skin color differences between caucasoid and mongoloid subjects.

    PubMed

    Anno, Sumiko; Abe, Takashi; Yamamoto, Takushi

    2008-01-01

    This study aimed to identify single nucleotide polymorphism (SNP) alleles at multiple loci associated with racial differences in skin color using SNP genotyping. A total of 122 Caucasians in Toledo, Ohio and 100 Mongoloids in Japan were genotyped for 20 SNPs in 7 candidate genes, encoding the Agouti signaling protein (ASIP), tyrosinase-related protein 1 (TYRP1), tyrosinase (TYR), melanocortin 1 receptor (MC1R), oculocutaneous albinism II (OCA2), microphthalmia-associated transcription factor (MITF), and myosin VA (MYO5A). Data were used to analyze associations between the 20 SNP alleles using linkage disequilibrium (LD). Combinations of SNP alleles were jointly tested under LD for associations with racial groups by performing a chi(2) test for independence. Results showed that SNP alleles at multiple loci can be considered the haplotype that contributes to significant differences between the two population groups and suggest a high probability of LD. Confirmation of these findings requires further study with other ethnic groups to analyze the associations between SNP alleles at multiple loci and skin color variation among races. PMID:18392143

  16. Application of a posteriori granddaughter and modified granddaughter designs to determine Holstein haplotype effects.

    PubMed

    Weller, J I; VanRaden, P M; Wiggans, G R

    2013-08-01

    A posteriori and modified granddaughter designs were applied to determine haplotype effects for Holstein bulls and cows with BovineSNP50 [~50,000 single nucleotide polymorphisms (SNP); Illumina Inc., San Diego, CA] genotypes. The a posteriori granddaughter design was applied to 52 sire families, each with ≥100 genotyped sons with genetic evaluations based on progeny tests. For 33 traits (milk, fat, and protein yields; fat and protein percentages; somatic cell score; productive life; daughter pregnancy rate; heifer and cow conception rates; service-sire and daughter calving ease; service-sire and daughter stillbirth; 18 conformation traits; and net merit), the analysis was applied to the autosomal segment with the SNP with the greatest effect in the genomic evaluation of each trait. All traits except 2 had a within-family haplotype effect. The same design was applied with the genetic evaluations of sons corrected for SNP effects associated with chromosomes besides the one under analysis. The number of within-family contrasts was 166 without adjustment and 211 with adjustment. Of the 52 bulls analyzed, 36 had BovineHD (high density; Illumina Inc.) genotypes that were used to test for concordance between sire quantitative trait loci and SNP genotypes; complete concordance was not obtained for any effects. Of the 31 traits with effects from the a posteriori granddaughter design, 21 were analyzed with the modified granddaughter design. Only sires with a contrast for the a posteriori granddaughter design and ≥200 granddaughters with a record usable for genetic evaluation were included. Calving traits could not be analyzed because individual cow evaluations were not computed. Eight traits had within-family haplotype effects. With respect to milk and fat yields and fat percentage, the results on Bos taurus autosome (BTA) 14 corresponded to the hypothesis that a missense mutation in the diacylglycerol O-acyltransferase 1 (DGAT1) gene is the main causative mutation

  17. SNP marker diversity in common bean (Phaseolus vulgaris L.).

    PubMed

    Cortés, Andrés J; Chavarro, Martha C; Blair, Matthew W

    2011-09-01

    Single nucleotide polymorphism (SNP) markers have become a genetic technology of choice because of their automation and high precision of allele calls. In this study, our goal was to develop 94 SNPs and test them across well-chosen common bean (Phaseolus vulgaris L.) germplasm. We validated and accessed SNP diversity at 84 gene-based and 10 non-genic loci using KASPar technology in a panel of 70 genotypes that have been used as parents of mapping populations and have been previously evaluated for SSRs. SNPs exhibited high levels of genetic diversity, an excess of middle frequency polymorphism, and a within-genepool mismatch distribution as expected for populations affected by sudden demographic expansions after domestication bottlenecks. This set of markers was useful for distinguishing Andean and Mesoamerican genotypes but less useful for distinguishing within each gene pool. In summary, slightly greater polymorphism and race structure was found within the Andean gene pool than within the Mesoamerican gene pool but polymorphism rate between genotypes was consistent with genepool and race identity. Our survey results represent a baseline for the choice of SNP markers for future applications because gene-associated SNPs could themselves be causative SNPs for traits. Finally, we discuss that the ideal genetic marker combination with which to carry out diversity, mapping and association studies in common bean should consider a mix of both SNP and SSR markers. PMID:21785951

  18. Ethnic heterogeneity of IRF6 AP-2α binding site promoter SNP association with nonsyndromic cleft lip and palate

    PubMed Central

    Blanton, Susan H.; Burt, Amber; Garcia, Elizabeth; Mulliken, John B.; Stal, Samuel; Hecht, Jacqueline T.

    2010-01-01

    Objective The goal of this study was to confirm the reported association between a noncoding SNP (rs642961) in IRF6 and nonsyndromic cleft lip and palate (NSCLP). Design, Setting and Participants Two SNPs in IRF6 (rs2235371 and rs64296) were genotyped in Hispanic and nonHispanic white multiplex (122) and simplex (308) NSCLP families. Linkage and family-based association analyses were performed on the individual SNPs as well as the 2-SNP haplotype. Results We find only modest evidence for an association with rs642961 and the 2-SNP haplotype. In contrast, we found strong evidence for association with rs2235371; this was most evident in the nonHispanic white simplex families. Conclusions While we confirm that variation in IRF6 is associated with NSCLP, our results do not support the reported association with SNP rs64296. Importantly, the association varies between ethnic groups. This finding underscores the need for evaluating additional variations in IRF6 across multiple populations to better determine its role in NSCLP. PMID:21039277

  19. Vitamin D Receptor Gene Polymorphisms and Haplotypes in Hungarian Patients with Idiopathic Inflammatory Myopathy

    PubMed Central

    Griger, Zoltán; Dankó, Katalin

    2015-01-01

    Idiopathic inflammatory myopathies are autoimmune diseases characterized by symmetrical proximal muscle weakness. Our aim was to identify a correlation between VDR polymorphisms or haplotypes and myositis. We studied VDR-BsmI, VDR-ApaI, VDR-TaqI, and VDR-FokI polymorphisms and haplotypes in 89 Hungarian poly-/dermatomyositis patients (69 females) and 93 controls (52 females). We did not obtain any significant differences for VDR-FokI, BsmI, ApaI, and TaqI genotypes and allele frequencies between patients with myositis and healthy individuals. There was no association of VDR polymorphisms with clinical manifestations and laboratory profiles in myositis patients. Men with myositis had a significantly different distribution of BB, Bb, and bb genotypes than female patients, control male individuals, and the entire control group. Distribution of TT, Tt, and tt genotypes was significantly different in males than in females in patient group. According to four-marker haplotype prevalence, frequencies of sixteen possible haplotypes showed significant differences between patient and control groups. The three most frequent haplotypes in patients were the fbAt, FBaT, and fbAT. Our findings may reveal that there is a significant association: Bb and Tt genotypes can be associated with myositis in the Hungarian population we studied. We underline the importance of our result in the estimated prevalence of four-marker haplotypes. PMID:25649962

  20. Haplotype diversity of 17 Y-chromosomal STR loci in the Bangladeshi population.

    PubMed

    Alam, Shafiul; Ali, Md Eunus; Ferdous, Ahmad; Hossain, Tania; Hasan, Md Mahamud; Akhteruzzaman, Sharif

    2010-02-01

    Haplotype and allele frequencies of 17 Y-chromosomal STR loci were determined in 216 unrelated Bangladeshi males. AmpFlSTR Y-filer PCR Amplification kit (Applied Biosystems) was used to type the following Y-STR markers: DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS438, DYS439, DYS437, DYS448, DYS458, DYS456, DYS635, and Y-GATA-H4. A total of 211 haplotypes for the 17 Y-STR markers were detected and, of these, 206 haplotypes were unique. The haplotype diversity was 0.9998, indicating a high potential for differentiating between male individuals in this population. Comparison analysis via Analysis of Molecular Variance (AMOVA) and construction of Neighbor Joining Tree revealed a close association of Bangladeshi population with Indian Gaddi and Southern Indian populations. PMID:20129457

  1. An Algorithm for Inferring Complex Haplotypes in a Region of Copy-Number Variation

    PubMed Central

    Kato, Mamoru; Nakamura, Yusuke; Tsunoda, Tatsuhiko

    2008-01-01

    Recent studies have extensively examined the large-scale genetic variants in the human genome known as copy-number variations (CNVs), and the universality of CNVs in normal individuals, along with their functional importance, has been increasingly recognized. However, the absence of a method to accurately infer alleles or haplotypes within a CNV region from high-throughput experimental data hampers the finer analyses of CNV properties and applications to disease-association studies. Here we developed an algorithm to infer complex haplotypes within a CNV region by using data obtained from high-throughput experimental platforms. We applied this algorithm to experimental data and estimated the population frequencies of haplotypes that can yield information on both sequences and numbers of DNA copies. These results suggested that the analysis of such complex haplotypes is essential for accurately detecting genetic differences within a CNV region between population groups. PMID:18639202

  2. Using Hamming Distance as Information for SNP-Sets Clustering and Testing in Disease Association Studies

    PubMed Central

    Wang, Charlotte; Kao, Wen-Hsin; Hsiao, Chuhsing Kate

    2015-01-01

    The availability of high-throughput genomic data has led to several challenges in recent genetic association studies, including the large number of genetic variants that must be considered and the computational complexity in statistical analyses. Tackling these problems with a marker-set study such as SNP-set analysis can be an efficient solution. To construct SNP-sets, we first propose a clustering algorithm, which employs Hamming distance to measure the similarity between strings of SNP genotypes and evaluates whether the given SNPs or SNP-sets should be clustered. A dendrogram can then be constructed based on such distance measure, and the number of clusters can be determined. With the resulting SNP-sets, we next develop an association test HDAT to examine susceptibility to the disease of interest. This proposed test assesses, based on Hamming distance, whether the similarity between a diseased and a normal individual differs from the similarity between two individuals of the same disease status. In our proposed methodology, only genotype information is needed. No inference of haplotypes is required, and SNPs under consideration do not need to locate in nearby regions. The proposed clustering algorithm and association test are illustrated with applications and simulation studies. As compared with other existing methods, the clustering algorithm is faster and better at identifying sets containing SNPs exerting a similar effect. In addition, the simulation studies demonstrated that the proposed test works well for SNP-sets containing a large proportion of neutral SNPs. Furthermore, employing the clustering algorithm before testing a large set of data improves the knowledge in confining the genetic regions for susceptible genetic markers. PMID:26302001

  3. Design and Characterization of a 52K SNP Chip for Goats

    PubMed Central

    Tosser-Klopp, Gwenola; Bardou, Philippe; Bouchez, Olivier; Cabau, Cédric; Crooijmans, Richard; Dong, Yang; Donnadieu-Tonon, Cécile; Eggen, André; Heuven, Henri C. M.; Jamli, Saadiah; Jiken, Abdullah Johari; Klopp, Christophe; Lawley, Cynthia T.; McEwan, John; Martin, Patrice; Moreno, Carole R.; Mulsant, Philippe; Nabihoudine, Ibouniyamine; Pailhoux, Eric; Palhière, Isabelle; Rupp, Rachel; Sarry, Julien; Sayre, Brian L.; Tircazes, Aurélie; Jun Wang; Wang, Wen; Zhang, Wenguang

    2014-01-01

    The success of Genome Wide Association Studies in the discovery of sequence variation linked to complex traits in humans has increased interest in high throughput SNP genotyping assays in livestock species. Primary goals are QTL detection and genomic selection. The purpose here was design of a 50–60,000 SNP chip for goats. The success of a moderate density SNP assay depends on reliable bioinformatic SNP detection procedures, the technological success rate of the SNP design, even spacing of SNPs on the genome and selection of Minor Allele Frequencies (MAF) suitable to use in diverse breeds. Through the federation of three SNP discovery projects consolidated as the International Goat Genome Consortium, we have identified approximately twelve million high quality SNP variants in the goat genome stored in a database together with their biological and technical characteristics. These SNPs were identified within and between six breeds (meat, milk and mixed): Alpine, Boer, Creole, Katjang, Saanen and Savanna, comprising a total of 97 animals. Whole genome and Reduced Representation Library sequences were aligned on >10 kb scaffolds of the de novo goat genome assembly. The 60,000 selected SNPs, evenly spaced on the goat genome, were submitted for oligo manufacturing (Illumina, Inc) and published in dbSNP along with flanking sequences and map position on goat assemblies (i.e. scaffolds and pseudo-chromosomes), sheep genome V2 and cattle UMD3.1 assembly. Ten breeds were then used to validate the SNP content and 52,295 loci could be successfully genotyped and used to generate a final cluster file. The combined strategy of using mainly whole genome Next Generation Sequencing and mapping on a contig genome assembly, complemented with Illumina design tools proved to be efficient in producing this GoatSNP50 chip. Advances in use of molecular markers are expected to accelerate goat genomic studies in coming years. PMID:24465974

  4. Recombination mapping using Boolean logic and high-density SNP genotyping for exome sequence filtering

    PubMed Central

    Markello, Thomas C.; Han, Ted; Carlson-Donohoe, Hannah; Ahaghotu, Chidi; Harper, Ursula; Jones, MaryPat; Chandrasekharappa, Settara; Anikster, Yair; Adams, David R.; Gahl, William A.; Boerkoel, Cornelius F.

    2012-01-01

    Whole genome sequence data for small pedigrees has been shown to provide sufficient information to resolve detailed haplotypes in small pedigrees. Using such information, recombinations can be mapped onto chromosomes, compared with the segregation of a disease of interest and used to filter genome sequence variants. We now show that relatively inexpensive SNP array data from small pedigrees can be used in a similar manner to provide a means of identifying regions of interest in exome sequencing projects. We demonstrate that in those situations where one can assume complete penetrance and parental DNA is available, SNP recombination mapping using Boolean logic identifies chromosomal regions identical to those detected by multipoint linkage using microsatellites but with much less computation. We further show that this approach is successful because the probability of a double crossover between informative SNP loci is negligible. Our observations provide a rationale for using SNP arrays and recombination mapping as a rapid and cost-effective means of incorporating chromosome segregation information into exome sequencing projects intended for disease-gene identification. PMID:22264778

  5. Development of the catfish 250K SNP array for genome-wide association studies

    PubMed Central

    2014-01-01

    Background Quantitative traits, such as disease resistance, are most often controlled by a set of genes involving a complex array of regulation. The dissection of genetic basis of quantitative traits requires large numbers of genetic markers with good genome coverage. The application of next-generation sequencing technologies has allowed discovery of over eight million SNPs in catfish, but the challenge remains as to how to efficiently and economically use such SNP resources for genetic analysis. Results In this work, we developed a catfish 250K SNP array using Affymetrix Axiom genotyping technology. The SNPs were obtained from multiple sources including gene-associated SNPs, anonymous genomic SNPs, and inter-specific SNPs. A set of 640K high-quality SNPs obtained following specific requirements of array design were submitted. A panel of 250,113 SNPs was finalized for inclusion on the array. The performance evaluated by genotyping individuals from wild populations and backcross families suggested the good utility of the catfish 250K SNP array. Conclusions This is the first high-density SNP array for catfish. The array should be a valuable resource for genome-wide association studies (GWAS), fine QTL mapping, high-density linkage map construction, haplotype analysis, and whole genome-based selection. PMID:24618043

  6. SSCP-SNP in pearl millet--a new marker system for comparative genetics.

    PubMed

    Bertin, I; Zhu, J H; Gale, M D

    2005-05-01

    A considerable array of genomic resources are in place in pearl millet, and marker-aided selection is already in use in the public breeding programme at ICRISAT. This paper describes experiments to extend these publicly available resources to a single nucleotide polymorphism (SNP)-based marker system. A new marker system, single-strand conformational polymorphism (SSCP)-SNP, was developed using annotated rice genomic sequences to initially predict the intron-exon borders in millet expressed sequence tags (ESTs) and then to design primers that would amplify across the introns. An adequate supply of millet ESTs was available for us to identify 299 homologues of single-copy rice genes in which the intron positions could be precisely predicted. PCR primers were then designed to amplify approximately 500-bp genomic fragments containing introns. Analysis of these fragments on SSCP gels revealed considerable polymorphism. A detailed DNA sequence analysis of variation at four of the SSCP-SNP loci over a panel of eight inbred genotypes showed complex patterns of variation, with about one SNP or indel (insertion-deletion) every 59 bp in the introns, but considerably fewer in the exons. About two-thirds of the variation was derived from SNPs and one-third from indels. Most haplotypes were detected by SSCP. As a marker system, SSCP-SNP has lower development costs than simple sequence repeats (SSRs), because much of the work is in silico, and similar deployment costs and through-put potential. The rates of polymorphism were lower but useable, with a mean PIC of 0.49 relative to 0.72 for SSRs in our eight inbred genotype panel screen. The major advantage of the system is in comparative applications. Syntenic information can be used to target SSCP-SNP markers to specific chromosomal regions or, conversely, SSCP-SNP markers can be used to unravel detailed syntenic relationships in specific parts of the genome. Finally, a preliminary analysis showed that the millet SSCP-SNP primers

  7. Haplotypes and mutations in Wilson disease

    SciTech Connect

    Thomas, G.R.; Roberts, E.A.; Cox, D.W.

    1995-06-01

    Wilson disease is a disorder of copper transport, resulting in neurological and hepatic damage due to copper toxicity. We have recently identified >20 mutations in the copper-transporting ATPase defective in this disease. Given the difficulties of searching for mutations in a gene spanning >80 kb of genomic DNA, haplotype data are important as a guide to mutation detection. Here we examine the haplotypes associated with specific mutations. We have extended previous studies of DNA haplotypes of dinucleotide-repeat polymorphisms (CA repeats) in the Wilson disease region to include an additional marker, in 58 families. These haplotypes, combining three markers (D13S314, D12S316, and D13S301), are usually specific for each different mutation, even though highly polymorphic CA repeat markers have been used. Haplotypes, as well as their accompanying mutations, differ between populations. In the patients whom we have studied, the haplotype data indicate that as many as 20 mutations may still be unidentified. The use of the haplotypes that we have identified provides an important guide for the identification of known mutations and can facilitate future mutation searches. 15 refs., 1 fig., 2 tabs.

  8. Characteristic beta-globin gene cluster haplotypes of Evenkis and Oroqens in north China.

    PubMed

    Shimizu, Koji; Marubayashi, Azusa; Tokimasa, Kozue; Harihara, Shinji; Omoto, Keiichi; Imanishi, Tadashi; Hao, Luping; Jin, Feng

    2004-10-01

    Haplotype frequencies of the beta-globin gene cluster were estimated for 114 Evenkis and 81 Oroqens from northeast China, and their characteristics were compared with those in Japanese, Koreans, and three Colombian Amerindian groups of South America (Wayuu, Kamsa, and Inga tribes). A major 5' subhaplotype (5' to the delta-globin gene) was + - - - - in Evenkis, whereas + - - - -, - + + - +, and - + - + + were the major subhaplotypes in Oroqens. One possible candidate for an ancestral 5' subhaplotype, - - - - -, was found in one Evenki (0.5%) and three Oroqen chromosomes (2.0%). They were observed as heterozygous forms for + ---- and -----. Major haplotypes were +-----+, + -----+-, and + - - - - + + in Evenkis, whereas they were +-----+,-++-+-+, +----+-, and -+-++-+ in Oroqens. The lowest Nei's genetic distance values of Evenkis or Oroqens based on the 5' subhaplotype frequency distributions were observed in relation to the Wayuu or Koreans, respectively, but those of Evenkis and Oroqens based on the haplotype frequency distributions were found in relation to Koreans. PMID:15757246

  9. Acute chest syndrome is associated with single nucleotide polymorphism-defined beta globin cluster haplotype in children with sickle cell anaemia.

    PubMed

    Bean, Christopher J; Boulet, Sheree L; Yang, Genyan; Payne, Amanda B; Ghaji, Nafisa; Pyle, Meredith E; Hooper, W Craig; Bhatnagar, Pallav; Keefer, Jeffrey; Barron-Casella, Emily A; Casella, James F; Debaun, Michael R

    2013-10-01

    Genetic diversity at the human β-globin locus has been implicated as a modifier of sickle cell anaemia (SCA) severity. However, haplotypes defined by restriction fragment length polymorphism sites across the β-globin locus have not been consistently associated with clinical phenotypes. To define the genetic structure at the β-globin locus more thoroughly, we performed high-density single nucleotide polymorphism (SNP) mapping in 820 children who were homozygous for the sickle cell mutation (HbSS). Genotyping results revealed very high linkage disequilibrium across a large region spanning the locus control region and the HBB (β-globin gene) cluster. We identified three predominant haplotypes accounting for 96% of the β(S) -carrying chromosomes in this population that could be distinguished using a minimal set of common SNPs. Consistent with previous studies, fetal haemoglobin level was significantly associated with β(S) -haplotypes. After controlling for covariates, an association was detected between haplotype and rate of hospitalization for acute chest syndrome (ACS) (incidence rate ratio 0·51, 95% confidence interval 0·29-0·89) but not incidence rate of vaso-occlusive pain or presence of silent cerebral infarct (SCI). Our results suggest that these SNP-defined β(S) -haplotypes may be associated with ACS, but not pain or SCI in a study population of children with SCA. PMID:23952145

  10. Haplotypes extending across ACE are associated with Alzheimer's disease.

    PubMed

    Kehoe, Patrick G; Katzov, Hagit; Feuk, Lars; Bennet, Anna M; Johansson, Boo; Wiman, Björn; de Faire, Ulf; Cairns, Nigel J; Wilcock, Gordon K; Brookes, Anthony J; Blennow, Kaj; Prince, Jonathan A

    2003-04-15

    Numerous genes have been implicated in Alzheimer's disease (AD), but, with the exception of a demonstrated association with the epsilon 4 allele of APOE, findings have not been consistently replicated across populations. One of the most widely studied is the gene for angiotensin I converting enzyme (ACE ). A meta-analysis of published data on a common Alu indel polymorphism in ACE was performed which indicated highly significant association of the insertion allele with AD (OR 1.30; 95% CI 1.19 - 1.41; P=4 x 10(-8)). To further explore the influence of ACE on AD, several single-nucleotide polymorphisms (SNPs) were genotyped in five independent populations represented by over 3100 individuals. Analyses based upon single markers and haplotypes revealed strong evidence of association in case-control models and also in a model examining the influence of variation in ACE upon cerebrospinal fluid levels of amyloid beta42 peptide (Abeta42). The most significant evidence for association with AD was found for an SNP, A-262T, located in the ACE promoter (OR 1.64; 95% CI 1.33 -1.94; P=2 x 10(-5)). Estimates of population attributable risk for the common allele of this SNP suggest that it, or an allele in tight linkage disequilibrium (LD) with it, may contribute to as much as 35% of AD in the general population. Results support a model whereby decreased ACE activity may influence AD susceptibility by a mechanism involving beta-amyloid metabolism. PMID:12668609

  11. Reliable reconstruction of HIV-1 whole genome haplotypes reveals clonal interference and genetic hitchhiking among immune escape variants

    PubMed Central

    2014-01-01

    Background Following transmission, HIV-1 evolves into a diverse population, and next generation sequencing enables us to detect variants occurring at low frequencies. Studying viral evolution at the level of whole genomes was hitherto not possible because next generation sequencing delivers relatively short reads. Results We here provide a proof of principle that whole HIV-1 genomes can be reliably reconstructed from short reads, and use this to study the selection of immune escape mutations at the level of whole genome haplotypes. Using realistically simulated HIV-1 populations, we demonstrate that reconstruction of complete genome haplotypes is feasible with high fidelity. We do not reconstruct all genetically distinct genomes, but each reconstructed haplotype represents one or more of the quasispecies in the HIV-1 population. We then reconstruct 30 whole genome haplotypes from published short sequence reads sampled longitudinally from a single HIV-1 infected patient. We confirm the reliability of the reconstruction by validating our predicted haplotype genes with single genome amplification sequences, and by comparing haplotype frequencies with observed epitope escape frequencies. Conclusions Phylogenetic analysis shows that the HIV-1 population undergoes selection driven evolution, with successive replacement of the viral population by novel dominant strains. We demonstrate that immune escape mutants evolve in a dependent manner with various mutations hitchhiking along with others. As a consequence of this clonal interference, selection coefficients have to be estimated for complete haplotypes and not for individual immune escapes. PMID:24996694

  12. Selection of Genetic Markers for Association Analyses, Using Linkage Disequilibrium and Haplotypes

    PubMed Central

    Meng, Zhaoling; Zaykin, Dmitri V.; Xu, Chun-Fang; Wagner, Michael; Ehm, Margaret G.

    2003-01-01

    The genotyping of closely spaced single-nucleotide polymorphism (SNP) markers frequently yields highly correlated data, owing to extensive linkage disequilibrium (LD) between markers. The extent of LD varies widely across the genome and drives the number of frequent haplotypes observed in small regions. Several studies have illustrated the possibility that LD or haplotype data could be used to select a subset of SNPs that optimize the information retained in a genomic region while reducing the genotyping effort and simplifying the analysis. We propose a method based on the spectral decomposition of the matrices of pairwise LD between markers, and we select markers on the basis of their contributions to the total genetic variation. We also modify Clayton’s “haplotype tagging SNP” selection method, which utilizes haplotype information. For both methods, we propose sliding window–based algorithms that allow the methods to be applied to large chromosomal regions. Our procedures require genotype information about a small number of individuals for an initial set of SNPs and selection of an optimum subset of SNPs that could be efficiently genotyped on larger numbers of samples while retaining most of the genetic variation in samples. We identify suitable parameter combinations for the procedures, and we show that a sample size of 50–100 individuals achieves consistent results in studies of simulated data sets in linkage equilibrium and LD. When applied to experimental data sets, both procedures were similarly effective at reducing the genotyping requirement while maintaining the genetic information content throughout the regions. We also show that haplotype-association results that Hosking et al. obtained near CYP2D6 were almost identical before and after marker selection. PMID:12796855

  13. Linkage and haplotype analysis for chemokine receptors clustered on chromosome 3p21.3 and transmitted in family pedigrees with asthma and atopy

    PubMed Central

    Al-Abdulhadi, Saleh A.; Al-Rabia, Mohammed W. O.

    2010-01-01

    BACKGROUND AND OBJECTIVES: Genomic scan analyses have suggested that the chemokine receptor cluster (CCR2, CCR3, CCR5 <300 kb span) on the short arm of chromosome 3 may contribute to susceptibility to HIV-1 infection and to the expression of a number of inflammatory diseases. Two single nucleotide polymorphisms (SNP) and a deletion in these chemokine receptors have also been found in case-control studies to be associated with susceptibility for asthma and related phenotypes. We extended these case-control studies by establishing whether these polymorphisms were in linkage and linkage disequilibrium with asthma and related phenotypes using linkage and haplotype analyses. METHODS: We genotyped 154 nuclear families identified through two child probands with physician-diagnosed asthma (453 unrelated individuals) including 303 unrelated parents and 150 unrelated children. Atopy was defined as a positive skin prick test (SPT 3 mm) to a panel of common inhaled allergens. RESULTS: From a panel of ten known SNPs, only three polymorphisms: –G190A in CCR2, –T51C in CCR3, and a 32 bp deletion in CCR5 were found to occur at clinically relevant frequencies. All 154 families were used for haplotype analysis but only 12 nuclear families were eligible for linkage analysis. Both analyses confirmed that the mutations were in linkage with asthma, but not with atopy. CONCLUSION: The chemokine receptor genes on 3p21.3 are significantly plausible candidate genes that can influence the expression of asthma. The previous association of the CCR5Δ32 deletion with protection from childhood asthma appears to be explained by linkage disequilibrium with the –G190A mutation in the CCR2 receptor gene. PMID:20220260

  14. Endothelial Nitric Oxide Synthase Haplotypes Are Associated with Preeclampsia in Maya Mestizo Women

    PubMed Central

    Díaz-Olguín, Lizbeth; Coral-Vázquez, Ramón Mauricio; Canto-Cetina, Thelma; Canizales-Quinteros, Samuel; Ramírez Regalado, Belem; Fernández, Genny; Canto, Patricia

    2011-01-01

    Preeclampsia is a specific disease of pregnancy and believed to have a genetic component. The aim of this study was to investigate if three polymorphisms in eNOS or their haplotypes are associated with preeclampsia in Maya mestizo women. A case-control study was performed where 127 preeclamptic patients and 263 controls were included. Genotyped and haplotypes for the -768T→C, intron 4 variants, Glu298Asp of eNOS were determined by PCR and real-time PCR allelic discrimination. Logistic regression analysis with adjustment for age and body mass index (BMI) was used to test for associations between genotype and preeclampsia under recessive, codominant and dominant models. Pairwise linkage disequilibrium between single nucleotide polymorphisms was calculated by direct correlation r2, and haplotype analysis was conducted. Women homozygous for the Asp298 allele showed an association of preeclampsia. In addition, analysis of the haplotype frequencies revealed that the -786C-4b-Asp298 haplotype was significantly more frequent in preeclamptic patients than in controls (0.143 vs. 0.041, respectively; OR = 3.01; 95% CI = 1.74–5.23; P = 2.9 × 10−4). Despite the Asp298 genotype in a recessive model associated with the presence of preeclampsia in Maya mestizo women, we believe that in this population the -786C-4b-Asp298 haplotype is a better genetic marker. PMID:21897002

  15. Nonrandom Wolbachia Infection Status of Drosophila melanogaster Strains with Different mtDNA Haplotypes

    PubMed Central

    Nunes, Maria D. S.; Nolte, Viola

    2008-01-01

    Wolbachia are maternally inherited bacteria, which typically spread in the host population by inducing cytoplasmic incompatibility (CI). In Drosophila melanogaster, Wolbachia is quite common but CI is variable, with most of the studies reporting low levels of CI. Surveying mitochondrial DNA (mtDNA) variation and infection status in a worldwide D. melanogaster collection, we found that the Wolbachia infection was not randomly distributed among flies with different mtDNA haplotypes. This preferential infection of some mtDNA haplotypes could be caused by a recent spread of mtDNA haplotypes associated with the infection. The comparison of contemporary D. melanogaster samples with lines collected more than 50 years ago shows that indeed one haplotype with a high incidence of Wolbachia infection has increased in frequency. Consistent with this observation, we found that the acquisition of a Wolbachia infection in a population from Crete was accompanied with an almost complete mtDNA replacement, with the Wolbachia-associated haplotype becoming abundant. Although it is difficult to identify the evolutionary forces causing the global increase of wMel, the parallel sweep of Wolbachia and an mtDNA haplotype suggests a fitness advantage of the Wolbachia infection. PMID:18780877

  16. Y chromosome haplotype analysis in Portuguese cattle breeds using SNPs and STRs.

    PubMed

    Ginja, Catarina; Telo da Gama, Luís; Penedo, Maria Cecilia T

    2009-01-01

    DNA samples from 307 males of 13 Portuguese native cattle breeds, 57 males of the 3 major exotic breeds in Portugal (Charolais, Friesian, and Limousin), and 5 Brahman (Bos indicus) were tested for 5 single nucleotide polymorphisms, 1 "indel," and 7 microsatellites specific to the Y chromosome. The 13 Y-haplotypes defined included 3 previously described patrilines (Y1, Y2, and Y3) and 10 new haplotypes within Bos taurus. Native cattle contained most of the diversity with 7 haplotypes (H2Y1, H3Y1, H5Y1, H7Y2, H8Y2, H10Y2, and H12Y2) found only in these breeds. H6Y2 and H11Y2 occurred in high frequency across breeds including the exotics. Introgression of Friesian cattle into Ramo Grande was inferred through their sharing of haplotype H4Y1. Among the native breeds, Mertolenga had the highest haplotype diversity (0.68 +/- 0.07), Brava de Lide was the least differentiated. The analyses of molecular variance showed significant (P < 0.0001) differences between breeds with more than 64% of the total genetic variation found among breeds within groups and 33-35% within breeds. The detection of INRA189-104 allele in 8 native breeds suggested influence of African cattle in breeds of the Iberian Peninsula. The presence in Portuguese breeds of Y1 patrilines, also found in aurochs, could represent more ancient local haplotypes. PMID:18832111

  17. Unique haplotypes of cacao trees as revealed by trnH-psbA chloroplast DNA

    PubMed Central

    Gutiérrez-López, Nidia; Ovando-Medina, Isidro; Salvador-Figueroa, Miguel; Molina-Freaner, Francisco; Avendaño-Arrazate, Carlos H.

    2016-01-01

    Cacao trees have been cultivated in Mesoamerica for at least 4,000 years. In this study, we analyzed sequence variation in the chloroplast DNA trnH-psbA intergenic spacer from 28 cacao trees from different farms in the Soconusco region in southern Mexico. Genetic relationships were established by two analysis approaches based on geographic origin (five populations) and genetic origin (based on a previous study). We identified six polymorphic sites, including five insertion/deletion (indels) types and one transversion. The overall nucleotide diversity was low for both approaches (geographic = 0.0032 and genetic = 0.0038). Conversely, we obtained moderate to high haplotype diversity (0.66 and 0.80) with 10 and 12 haplotypes, respectively. The common haplotype (H1) for both networks included cacao trees from all geographic locations (geographic approach) and four genetic groups (genetic approach). This common haplotype (ancient) derived a set of intermediate haplotypes and singletons interconnected by one or two mutational steps, which suggested directional selection and event purification from the expansion of narrow populations. Cacao trees from Soconusco region were grouped into one cluster without any evidence of subclustering based on AMOVA (FST = 0) and SAMOVA (FST = 0.04393) results. One population (Mazatán) showed a high haplotype frequency; thus, this population could be considered an important reservoir of genetic material. The indels located in the trnH-psbA intergenic spacer of cacao trees could be useful as markers for the development of DNA barcoding. PMID:27076998

  18. Haplotype-Based Study of the Association of Alcohol Metabolizing Genes with Alcohol Dependence in Four Independent Populations

    PubMed Central

    Liu, Jixia; Zhou, Zhifeng; Hodgkinson, Colin A.; Yuan, Qiaoping; Shen, Pei-Hong; Mulligan, Connie J.; Wang, Alex; Gray, Rebecca R.; Roy, Alec; Virkkunen, Matti; Goldman, David; Enoch, Mary-Anne

    2010-01-01

    Background Ethanol is metabolized by two rate limiting reactions: alcohol dehydrogenases (ADH) convert ethanol to acetaldehyde, subsequently metabolized to acetate by aldehyde dehydrogenases (ALDH). Approximately 50% of East Asians have genetic variants that significantly impair this pathway and influence alcohol dependence (AD) vulnerability. We investigated whether variation in alcohol metabolism genes might alter the AD risk in four non-East Asian populations by performing systematic haplotype association analyses in order to maximize the chances of capturing functional variation. Methods Haplotype-tagging SNPs were genotyped using the Illumina GoldenGate platform. Genotypes were available for 40 SNPs across the ADH genes cluster and 24 SNPs across the two ALDH genes in four diverse samples that included cases (lifetime AD) and controls (no Axis 1 disorders). The case, control sample sizes were: Finnish Caucasians: 232, 194; African Americans: 267, 422; Plains American Indians: 226, 110; Southwestern American (SW) Indians: 317, 72. Results In all four populations, as well as HapMap populations, five haplotype blocks were identified across the ADH gene cluster: (1) ADH5-ADH4; (2) ADH6-ADH1A-ADH1B; (3) ADH1C; (4) intergenic; (5) ADH7. The ALDH1A1 gene was defined by four blocks and ALDH2 by one block. No haplotype or SNP association results were significant after correction for multiple comparisons; however several results, particularly for ALDH1A1 and ADH4, replicated earlier findings. There was an ALDH1A1 block 1 and 2 (extending from intron 5 to the 3′ UTR) yin yang haplotype (haplotypes that have opposite allelic configuration) association with AD in the Finns driven by SNPs rs3764435 and rs2303317 respectively, and an ALDH1A1 block 3 (including the promoter region) yin yang haplotype association in SW Indians driven by 5 SNPs, all in allelic identity. The ADH4 SNP rs3762894 was associated with AD in Plains Indians. Conclusions The systematic evaluation of

  19. Combination Testing Using a Single MSH5 Variant alongside HLA Haplotypes Improves the Sensitivity of Predicting Coeliac Disease Risk in the Polish Population

    PubMed Central

    Dabrowska, Michalina; Goryca, Krzysztof; Piatkowska, Magdalena; Kluska, Anna; Mikula, Michal; Karczmarski, Jakub; Oralewska, Beata; Rybak, Anna; Socha, Jerzy; Balabas, Aneta; Zeber-Lubecka, Natalia; Ambrozkiewicz, Filip; Konopka, Ewa; Trojanowska, Ilona; Zagroba, Malgorzata; Szperl, Malgorzata; Ostrowski, Jerzy

    2015-01-01

    Assessment of non-HLA variants alongside standard HLA testing was previously shown to improve the identification of potential coeliac disease (CD) patients. We intended to identify new genetic variants associated with CD in the Polish population that would improve CD risk prediction when used alongside HLA haplotype analysis. DNA samples of 336 CD and 264 unrelated healthy controls were used to create DNA pools for a genome wide association study (GWAS). GWAS findings were validated with individual HLA tag single nucleotide polymorphism (SNP) typing of 473 patients and 714 healthy controls. Association analysis using four HLA-tagging SNPs showed that, as was found in other populations, positive predicting genotypes (HLA-DQ2.5/DQ2.5, HLA-DQ2.5/DQ2.2, and HLA-DQ2.5/DQ8) were found at higher frequencies in CD patients than in healthy control individuals in the Polish population. Both CD-associated SNPs discovered by GWAS were found in the CD susceptibility region, confirming the previously-determined association of the major histocompatibility (MHC) region with CD pathogenesis. The two most significant SNPs from the GWAS were rs9272346 (HLA-dependent; localized within 1 Kb of DQA1) and rs3130484 (HLA-independent; mapped to MSH5). Specificity of CD prediction using the four HLA-tagging SNPs achieved 92.9%, but sensitivity was only 45.5%. However, when a testing combination of the HLA-tagging SNPs and the MSH5 SNP was used, specificity decreased to 80%, and sensitivity increased to 74%. This study confirmed that improvement of CD risk prediction sensitivity could be achieved by including non-HLA SNPs alongside HLA SNPs in genetic testing. PMID:26406233

  20. Y-chromosomal STR haplotypes in Central Thai population.

    PubMed

    Siriboonpiputtana, T; Jomsawat, U; Rinthachai, T; Thanakitgosate, J; Shotivaranon, J; Limsuwanachot, N; Polyorat, P; Rerkamnuaychoke, B

    2010-04-01

    12 Y-STR loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS438, DYS439 and DYS437) were typed with PowerPlex Y System (Promega, USA) in a total sample of 501 unrelated males from the central part of Thailand. Allele frequencies and gene diversity for each Y-STR locus were determined. Haplotype diversity from the combined 12 Y-STR loci was 0.9996. The present results can be used as Thai ethnic genetic information resources in routine forensic analysis. PMID:20215020

  1. Association of MAPT haplotypes with Alzheimer’s disease risk and MAPT brain gene expression levels

    PubMed Central

    2014-01-01

    Introduction MAPT encodes for tau, the predominant component of neurofibrillary tangles that are neuropathological hallmarks of Alzheimer’s disease (AD). Genetic association of MAPT variants with late-onset AD (LOAD) risk has been inconsistent, although insufficient power and incomplete assessment of MAPT haplotypes may account for this. Methods We examined the association of MAPT haplotypes with LOAD risk in more than 20,000 subjects (n-cases = 9,814, n-controls = 11,550) from Mayo Clinic (n-cases = 2,052, n-controls = 3,406) and the Alzheimer’s Disease Genetics Consortium (ADGC, n-cases = 7,762, n-controls = 8,144). We also assessed associations with brain MAPT gene expression levels measured in the cerebellum (n = 197) and temporal cortex (n = 202) of LOAD subjects. Six single nucleotide polymorphisms (SNPs) which tag MAPT haplotypes with frequencies greater than 1% were evaluated. Results H2-haplotype tagging rs8070723-G allele associated with reduced risk of LOAD (odds ratio, OR = 0.90, 95% confidence interval, CI = 0.85-0.95, p = 5.2E-05) with consistent results in the Mayo (OR = 0.81, p = 7.0E-04) and ADGC (OR = 0.89, p = 1.26E-04) cohorts. rs3785883-A allele was also nominally significantly associated with LOAD risk (OR = 1.06, 95% CI = 1.01-1.13, p = 0.034). Haplotype analysis revealed significant global association with LOAD risk in the combined cohort (p = 0.033), with significant association of the H2 haplotype with reduced risk of LOAD as expected (p = 1.53E-04) and suggestive association with additional haplotypes. MAPT SNPs and haplotypes also associated with brain MAPT levels in the cerebellum and temporal cortex of AD subjects with the strongest associations observed for the H2 haplotype and reduced brain MAPT levels (β = -0.16 to -0.20, p = 1.0E-03 to 3.0E-03). Conclusions These results confirm the previously reported MAPT H2 associations with LOAD risk in two large series, that this haplotype has the strongest

  2. Ribosomal DNA haplotype distribution of Bursaphelenchus xylophilus in Kyushu and Okinawa islands, Japan.

    PubMed

    Nose, Mine; Shiraishi, Susumu; Miyahara, Fumihiko; Ohira, Mineko; Matsunaga, Koji; Tobase, Masashi; Koyama, Takao; Yoshimoto, Kikuo

    2009-09-01

    Ribosomal DNA region sequences (partial 18S, 28S and complete ITS1, 5.8S, and ITS2) of the pinewood nematode (Bursaphelenchus xylophilus) were obtained from DNA extracted directly from wood pieces collected from wilted pine trees throughout the Kyushu and Okinawa islands, Japan. Either a 2569bp or 2573bp sequence was obtained from 88 of 143 samples. Together with the 45 rDNA sequences of pinewood nematode isolates previously reported, there were eight single nucleotide polymorphisms and two indels of two bases. Based on these mutations, nine haplotypes were estimated. The haplotype frequencies differed among regions in Kyushu island (northwest, northeast and center, southeast, and southwest), and the distribution was consistent with the invasion and spreading routes of the pinewood nematode previously estimated from past records of pine wilt and wood importation. There was no significant difference in haplotype frequencies among the collection sites on Okinawa island. PMID:22736814

  3. A haplotype framework for cystic fibrosis mutations in Iran.

    PubMed

    Elahi, Elahe; Khodadad, Ahmad; Kupershmidt, Ilya; Ghasemi, Fereshteh; Alinasab, Babak; Naghizadeh, Ramin; Eason, Robert G; Amini, Mahshid; Esmaili, Mehran; Esmaeili Dooki, Mohammad R; Sanati, Mohammad H; Davis, Ronald W; Ronaghi, Mostafa; Thorstenson, Yvonne R

    2006-02-01

    This is the first comprehensive profile of cystic fibrosis transmembrane conductance regulator (CFTR) mutations and their corresponding haplotypes in the Iranian population. All of the 27 CFTR exons of 60 unrelated Iranian CF patients were sequenced to identify disease-causing mutations. Eleven core haplotypes of CFTR were identified by genotyping six high-frequency simple nucleotide polymorphisms. The carrier frequency of 2.5 in 100 (1 in 40) was estimated from the frequency of heterozygous patients and suggests that contrary to popular belief, cystic fibrosis may be a common, under-diagnosed disease in Iran. A heterogeneous mutation spectrum was observed at the CFTR locus in 60 cystic fibrosis (CF) patients from Iran. Twenty putative disease-causing mutations were identified on 64 (53%) of the 120 chromosomes. The five most common Iranian mutations together represented 37% of the expected mutated alleles. The most frequent mutation, DeltaF508 (p.F508del), represented only 16% of the expected mutated alleles. The next most frequent mutations were c.1677del2 (p.515fs) at 7.5%, c.4041C>G (p.N1303K) at 5.6%, c.2183AA>G (p.684fs) at 5%, and c.3661A>T (p.K1177X) at 2.5%. Three of the five most frequent Iranian mutations are not included in a commonly used panel of CF mutations, underscoring the importance of identifying geographic-specific mutations in this population. PMID:16436643

  4. A Haplotype Framework for Cystic Fibrosis Mutations in Iran

    PubMed Central

    Elahi, Elahe; Khodadad, Ahmad; Kupershmidt, Ilya; Ghasemi, Fereshteh; Alinasab, Babak; Naghizadeh, Ramin; Eason, Robert G.; Amini, Mahshid; Esmaili, Mehran; Esmaeili Dooki, Mohammad R.; Sanati, Mohammad H.; Davis, Ronald W.; Ronaghi, Mostafa; Thorstenson, Yvonne R.

    2006-01-01

    This is the first comprehensive profile of cystic fibrosis transmembrane conductance regulator (CFTR) mutations and their corresponding haplotypes in the Iranian population. All of the 27 CFTR exons of 60 unrelated Iranian CF patients were sequenced to identify disease-causing mutations. Eleven core haplotypes of CFTR were identified by genotyping six high-frequency simple nucleotide polymorphisms. The carrier frequency of 2.5 in 100 (1 in 40) was estimated from the frequency of heterozygous patients and suggests that contrary to popular belief, cystic fibrosis may be a common, under-diagnosed disease in Iran. A heterogeneous mutation spectrum was observed at the CFTR locus in 60 cystic fibrosis (CF) patients from Iran. Twenty putative disease-causing mutations were identified on 64 (53%) of the 120 chromosomes. The five most common Iranian mutations together represented 37% of the expected mutated alleles. The most frequent mutation, ΔF508 (p.F508del), represented only 16% of the expected mutated alleles. The next most frequent mutations were c.1677del2 (p.515fs) at 7.5%, c.4041C>G (p.N1303K) at 5.6%, c.2183AA>G (p.684fs) at 5%, and c.3661A>T (p.K1177X) at 2.5%. Three of the five most frequent Iranian mutations are not included in a commonly used panel of CF mutations, underscoring the importance of identifying geographic-specific mutations in this population. PMID:16436643

  5. Wide distribution and altitude correlation of an archaic high-altitude-adaptive EPAS1 haplotype in the Himalayas.

    PubMed

    Hackinger, Sophie; Kraaijenbrink, Thirsa; Xue, Yali; Mezzavilla, Massimo; Asan; van Driem, George; Jobling, Mark A; de Knijff, Peter; Tyler-Smith, Chris; Ayub, Qasim

    2016-04-01

    High-altitude adaptation in Tibetans is influenced by introgression of a 32.7-kb haplotype from the Denisovans, an extinct branch of archaic humans, lying within the endothelial PAS domain protein 1 (EPAS1), and has also been reported in Sherpa. We genotyped 19 variants in this genomic region in 1507 Eurasian individuals, including 1188 from Bhutan and Nepal residing at altitudes between 86 and 4550 m above sea level. Derived alleles for five SNPs characterizing the core Denisovan haplotype (AGGAA) were present at high frequency not only in Tibetans and Sherpa, but also among many populations from the Himalayas, showing a significant correlation with altitude (Spearman's correlation coefficient = 0.75, p value 3.9 × 10(-11)). Seven East- and South-Asian 1000 Genomes Project individuals shared the Denisovan haplotype extending beyond the 32-kb region, enabling us to refine the haplotype structure and identify a candidate regulatory variant (rs370299814) that might be interacting in an additive manner with the derived G allele of rs150877473, the variant previously associated with high-altitude adaptation in Tibetans. Denisovan-derived alleles were also observed at frequencies of 3-14% in the 1000 Genomes Project African samples. The closest African haplotype is, however, separated from the Asian high-altitude haplotype by 22 mutations whereas only three mutations, including rs150877473, separate the Asians from the Denisovan, consistent with distant shared ancestry for African and Asian haplotypes and Denisovan adaptive introgression. PMID:26883865

  6. Whole-Genome Analysis of Diversity and SNP-Major Gene Association in Peach Germplasm

    PubMed Central

    Micheletti, Diego; Dettori, Maria Teresa; Micali, Sabrina; Aramini, Valeria; Pacheco, Igor; Da Silva Linge, Cassia; Foschi, Stefano; Banchi, Elisa; Barreneche, Teresa; Quilot-Turion, Bénédicte; Lambert, Patrick; Pascal, Thierry; Iglesias, Ignasi; Carbó, Joaquim; Wang, Li-rong; Ma, Rui-juan; Li, Xiong-wei; Gao, Zhong-shan; Nazzicari, Nelson; Troggio, Michela; Bassi, Daniele; Rossini, Laura; Verde, Ignazio; Laurens, François; Arús, Pere; Aranzana, Maria José

    2015-01-01

    Peach was domesticated in China more than four millennia ago and from there it spread world-wide. Since the middle of the last century, peach breeding programs have been very dynamic generating hundreds of new commercial varieties, however, in most cases such varieties derive from a limited collection of parental lines (founders). This is one reason for the observed low levels of variability of the commercial gene pool, implying that knowledge of the extent and distribution of genetic variability in peach is critical to allow the choice of adequate parents to confer enhanced productivity, adaptation and quality to improved varieties. With this aim we genotyped 1,580 peach accessions (including a few closely related Prunus species) maintained and phenotyped in five germplasm collections (four European and one Chinese) with the International Peach SNP Consortium 9K SNP peach array. The study of population structure revealed the subdivision of the panel in three main populations, one mainly made up of Occidental varieties from breeding programs (POP1OCB), one of Occidental landraces (POP2OCT) and the third of Oriental accessions (POP3OR). Analysis of linkage disequilibrium (LD) identified differential patterns of genome-wide LD blocks in each of the populations. Phenotypic data for seven monogenic traits were integrated in a genome-wide association study (GWAS). The significantly associated SNPs were always in the regions predicted by linkage analysis, forming haplotypes of markers. These diagnostic haplotypes could be used for marker-assisted selection (MAS) in modern breeding programs. PMID:26352671

  7. DASH: a method for identical-by-descent haplotype mapping uncovers association with recent variation.

    PubMed

    Gusev, Alexander; Kenny, Eimear E; Lowe, Jennifer K; Salit, Jaqueline; Saxena, Richa; Kathiresan, Sekar; Altshuler, David M; Friedman, Jeffrey M; Breslow, Jan L; Pe'er, Itsik

    2011-06-10

    Rare variants affecting phenotype pose a unique challenge for human genetics. Although genome-wide association studies have successfully detected many common causal variants, they are underpowered in identifying disease variants that are too rare or population-specific to be imputed from a general reference panel and thus are poorly represented on commercial SNP arrays. We set out to overcome these challenges and detect association between disease and rare alleles using SNP arrays by relying on long stretches of genomic sharing that are identical by descent. We have developed an algorithm, DASH, which builds upon pairwise identical-by-descent shared segments to infer clusters of individuals likely to be sharing a single haplotype. DASH constructs a graph with nodes representing individuals and links on the basis of such segments spanning a locus and uses an iterative minimum cut algorithm to identify densely connected components. We have applied DASH to simulated data and diverse GWAS data sets by constructing haplotype clusters and testing them for association. In simulations we show this approach to be significantly more powerful than single-marker testing in an isolated population that is from Kosrae, Federated States of Micronesia and has abundant IBD, and we provide orthogonal information for rare, recent variants in the outbred Wellcome Trust Case-Control Consortium (WTCCC) data. In both cohorts, we identified a number of haplotype associations, five such loci in the WTCCC data and ten in the isolated, that were conditionally significant beyond any individual nearby markers. We have replicated one of these loci in an independent European cohort and identified putative structural changes in low-pass whole-genome sequence of the cluster carriers. PMID:21620352

  8. Haplotypes of RHO polymorphisms and susceptibility to age-related macular degeneration

    PubMed Central

    Tang, Kun; Wang, Wei; Wang, Qun; Wang, Liqiang; Bai, Hua; Jiang, Yanming; Huang, Yifei

    2015-01-01

    Objective: To investigate whether haplotypes of rhodopsin (RHO) polymorphisms including rs7984, rs2855552, rs2855557 and rs2410 were associated with age-related macular degeneration (AMD) risk in Chinese Han population. Methods: Genotypes of rs7984, rs2855552, rs2855557 and rs2410 were detected with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 186 cases and 196 healthy controls. Then, the haplotypes were established with Haploview 4.2 software. And the effects of clinical charactersitics on the frequency of GTTG haplotype were also analyzed. Odds ratios (ORs) with 95% confidence interval (95% CI) were utilized to assess the relationship of haplotypes and genotypes of RHO polymorphisms with susceptibility to AMD. Results: Genotype distribution of all polymorphisms in control group were all in agreement with Hardy-Weinberg equilibrium (HWE) (P>0.05). In the analysis, we found that mutant alleles of rs7984 and rs2855557 were both associated with increased risk of AMD. For genotype analysis, rs7984 AA and rs2855557AA, rs2410GG genotypes all could increase the risk for AMD (OR=1.905, 95% CI=1.143-3.174; OR=2.226, 95% CI=1.261-3.932; OR=2.073, 95% CI=1.105-3.888). However, rs2855552 showed no effects on the onset of AMD. Compared with GTTA, the haplotypes of GGTG, ATAA and GTTG were all related with AMD susceptibility. Further analysis suggested that age, hypertension and hyperlipidemia history play important roles in the frequency alteration of GTTG haplotype. Conclusion: RHO polymorphisms (rs7984, rs2855557 and rs2410) and haplotypes may confer remarkable susceptibility to AMD. Further investigation showed that gene and environmental factors may work together in the pathogenesis of AMD. PMID:26045836

  9. WinHAP2: an extremely fast haplotype phasing program for long genotype sequences

    PubMed Central

    2014-01-01

    Background The haplotype phasing problem tries to screen for phenotype associated genomic variations from millions of candidate data. Most of the current computer programs handle this problem with high requirements of computing power and memory. By replacing the computation-intensive step of constructing the maximum spanning tree with a heuristics of estimated initial haplotype, we released the WinHAP algorithm version 1.0, which outperforms the other algorithms in terms of both running speed and overall accuracy. Results This work further speeds up the WinHAP algorithm to version 2.0 (WinHAP2) by utilizing the divide-and-conquer strategy and the OpenMP parallel computing mode. WinHAP2 can phase 500 genotypes with 1,000,000 SNPs using just 12.8 MB in memory and 2.5 hours on a personal computer, whereas the other programs require unacceptable memory or running times. The parallel running mode further improves WinHAP2's running speed with several orders of magnitudes, compared with the other programs, including Beagle, SHAPEIT2 and 2SNP. Conclusions WinHAP2 is an extremely fast haplotype phasing program which can handle a large-scale genotyping study with any number of SNPs in the current literature and at least in the near future. PMID:24884701

  10. CXCR1 and CXCR2 haplotypes synergistically modulate cystic fibrosis lung disease.

    PubMed

    Kormann, Michael S D; Hector, Andreas; Marcos, Veronica; Mays, Lauren E; Kappler, Matthias; Illig, Thomas; Klopp, Norman; Zeilinger, Sonja; Carevic, Melanie; Rieber, Nikolaus; Eickmeier, Olaf; Zielen, Stefan; Gaggar, Amit; Moepps, Barbara; Griese, Matthias; Hartl, Dominik

    2012-06-01

    Cystic fibrosis (CF) lung disease severity is largely independent on the CF transmembrane conductance regulator (CFTR) genotype, indicating the contribution of genetic modifiers. The chemokine receptors CXCR1 and CXCR2 have been found to play essential roles in the pathogenesis of CF lung disease. Here, we determine whether genetic variation of CXCR1 and CXCR2 influences CF lung disease severity. Genomic DNA of CF patients in Germany (n = 442) was analysed for common variations in CXCR1 and CXCR2 using a single-nucleotide polymorphism (SNP) tagging approach. Associations of CXCR1 and CXCR2 SNPs and haplotypes with CF lung disease severity, CXCR1 and CXCR2 expression, and neutrophil effector functions were assessed. Four SNPs in CXCR1 and three in CXCR2 strongly correlated with age-adjusted lung function in CF patients. SNPs comprising haplotypes CXCR1_Ha and CXCR2_Ha were in high linkage disequilibrium and patients heterozygous for the CXCR1-2 haplotype cluster (CXCR1-2_Ha) had lower lung function compared with patients with homozygous wild-type alleles (forced expiratory volume in 1 s ≤ 70% predicted, OR 7.24; p = 2.30 × 10(-5)). CF patients carrying CXCR1-2_Ha showed decreased CXCR1 combined with increased CXCR2 mRNA and protein expression, and displayed disturbed antibacterial effector functions. CXCR1 and CXCR2 genotypes modulate lung function and antibacterial host defence in CF lung disease. PMID:22088968

  11. Cannabis receptor haplotype associated with fewer cannabis dependence symptoms in adolescents.

    PubMed

    Hopfer, Christian J; Young, Susan E; Purcell, Shaun; Crowley, Thomas J; Stallings, Michael C; Corley, Robin P; Rhee, Soo Hyun; Smolen, Andrew; Krauter, Ken; Hewitt, John K; Ehringer, Marissa A

    2006-12-01

    Cannabis is a major substance of abuse, and the gene encoding for the central cannabinoid receptor (CNR1) is a logical candidate gene for vulnerability toward developing symptoms of cannabis dependence. We studied four single-nucleotide polymorphisms (SNPs) in the CNR1 gene for association with having one or more symptoms of cannabis dependence in 541 adolescent subjects who had all tried cannabis five or more times. Cases (327) were defined as those who had tried marijuana and developed one or more symptoms, and controls (214) as those who had tried marijuana but developed no dependence symptoms. Cannabis dependence symptoms were assessed in these youth when they were 17 or older with the Composite International Diagnostic Interview--Substance Abuse Module. Univariate (single-marker) association tests demonstrated that SNP rs806380, located in intron 2 of the CNR1 gene, was significantly associated with developing one or more cannabis dependence symptoms, with the G allele having a protective effect (P < 0.02). This was consistent with the results of the global haplotype test (P < 0.01). One of the common haplotypes examined (present in 21% of the subjects) was significantly associated with a lower rate of having one or more cannabis dependence symptoms. Our findings provide evidence suggesting that a common CNR1 haplotype is associated with developing fewer cannabis dependence symptoms among adolescents who have experimented with cannabis. PMID:16917946

  12. Evidence for a SULT4A1 haplotype correlating with baseline psychopathology and atypical antipsychotic response

    PubMed Central

    Ramsey, Timothy L; Meltzer, Herbert Y; Brock, Guy N; Mehrotra, Bharat; Jayathilake, Karu; Bobo, William V; Brennan, Mark D

    2011-01-01

    Aim This study evaluated the impact of SULT4A1 gene variation on psychopathology and antipsychotic drug response in Caucasian subjects from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) study and a replication sample. Patients & methods SULT4A1 haplotypes were determined using SNP data. The relationship to baseline psychopathology was evaluated using linear regression of Positive and Negative Syndrome Scale (PANSS) total score. Drug response was evaluated using Mixed Model Repeat Measures (MMRM) for change in PANSS. Results For the CATIE sample, patients carrying a haplotype designated SULT4A1-1(+) displayed higher baseline PANSS (p = 0.03) and, when treated with olanzapine, demonstrated a significant interaction with time (p = 0.009) in the MMRM. SULT4A1-1(+) patients treated with olanzapine displayed improved response compared with SULT4A1-1(−) patients treated with olanzapine (p = 0.008) or to SULT4A1-1(+) patients treated with risperidone (p = 0.006). In the replication sample, SULT4A1-1(+) patients treated with olanzapine demonstrated greater improvement than SULT4A1-1(−) patients treated with olanzapine (p = 0.05) or than SULT4A1-1(+) patients treated with risperidone (p = 0.05). Conclusion If validated, determination of SULT4A1-1 haplotype status might be useful for identifying patients who show an enhanced response to long-term olanzapine treatment. PMID:21521020

  13. Sickle cell disease in a Brazilian population from Sao Paulo: a study of the beta s haplotypes.

    PubMed

    Goncalves, M S; Nechtman, J F; Figueiredo, M S; Kerbauy, J; Arruda, V R; Sonati, M F; Saad, S O; Costa, F F; Stoming, T A

    1994-01-01

    In this study we have determined the frequency of beta S haplotypes in a Brazilian sickle cell disease population from Sao Paulo, Brazil, by analyzing sequence variations in the immediate 5' flanking and second intervening sequence (IVSII) regions of the gamma globin genes. This association between sequence differences and beta s haplotype backgrounds was determined by screening genomic DNA samples using dot blot analysis of polymerase chain reaction products. We studied 148 beta s chromosomes, and found that haplotype 20 (CAR or Bantu) significantly predominated in this population. This is in agreement with the findings of the historical Portuguese Atlantic slave trade from Africa to South America. PMID:7860085

  14. Estimation of Pairwise Identity by Descent From Dense Genetic Marker Data in a Population Sample of Haplotypes

    PubMed Central

    Browning, Sharon R.

    2008-01-01

    I present a new approach for calculating probabilities of identity by descent for pairs of haplotypes. The approach is based on a joint hidden Markov model for haplotype frequencies and identity by descent (IBD). This model allows for linkage disequilibrium, and the method can be applied to very dense marker data. The method has high power for detecting IBD tracts of genetic length of 1 cM, with the use of sufficiently dense markers. This enables detection of pairwise IBD between haplotypes from individuals whose most recent common ancestor lived up to 50 generations ago. PMID:18430938

  15. Detecting Susceptibility to Breast Cancer with SNP-SNP Interaction Using BPSOHS and Emotional Neural Networks.

    PubMed

    Wang, Xiao; Peng, Qinke; Fan, Yue

    2016-01-01

    Studies for the association between diseases and informative single nucleotide polymorphisms (SNPs) have received great attention. However, most of them just use the whole set of useful SNPs and fail to consider the SNP-SNP interactions, while these interactions have already been proven in biology experiments. In this paper, we use a binary particle swarm optimization with hierarchical structure (BPSOHS) algorithm to improve the effective of PSO for the identification of the SNP-SNP interactions. Furthermore, in order to use these SNP interactions in the susceptibility analysis, we propose an emotional neural network (ENN) to treat SNP interactions as emotional tendency. Different from the normal architecture, just as the emotional brain, this architecture provides a specific path to treat the emotional value, by which the SNP interactions can be considered more quickly and directly. The ENN helps us use the prior knowledge about the SNP interactions and other influence factors together. Finally, the experimental results prove that the proposed BPSOHS_ENN algorithm can detect the informative SNP-SNP interaction and predict the breast cancer risk with a much higher accuracy than existing methods. PMID:27294121

  16. Detecting Susceptibility to Breast Cancer with SNP-SNP Interaction Using BPSOHS and Emotional Neural Networks

    PubMed Central

    Wang, Xiao; Fan, Yue

    2016-01-01

    Studies for the association between diseases and informative single nucleotide polymorphisms (SNPs) have received great attention. However, most of them just use the whole set of useful SNPs and fail to consider the SNP-SNP interactions, while these interactions have already been proven in biology experiments. In this paper, we use a binary particle swarm optimization with hierarchical structure (BPSOHS) algorithm to improve the effective of PSO for the identification of the SNP-SNP interactions. Furthermore, in order to use these SNP interactions in the susceptibility analysis, we propose an emotional neural network (ENN) to treat SNP interactions as emotional tendency. Different from the normal architecture, just as the emotional brain, this architecture provides a specific path to treat the emotional value, by which the SNP interactions can be considered more quickly and directly. The ENN helps us use the prior knowledge about the SNP interactions and other influence factors together. Finally, the experimental results prove that the proposed BPSOHS_ENN algorithm can detect the informative SNP-SNP interaction and predict the breast cancer risk with a much higher accuracy than existing methods. PMID:27294121

  17. Sporadic inclusion body myositis in Japanese is associated with the MHC ancestral haplotype 52.1.

    PubMed

    Scott, Adrian Phillip; Allcock, Richard James Nigel; Mastaglia, Frank; Nishino, Ichizo; Nonaka, Ikuya; Laing, Nigel

    2006-05-01

    In Caucasians, sporadic inclusion body myositis has been associated with the MHC ancestral haplotypes; HLA-A1, B8, DR3 (8.1AH) and HLA-B35, DR1 (35.2AH). It is not known whether these haplotypes carry susceptibility for the disease in other ethnic groups. We report here the results of HLA-B and -DRB1 typing using a high-resolution sequence-based technique in a cohort of 31 Japanese patients with definite sIBM. Patient allele frequencies were 40.3% for HLA-B*5201 (10.7% in controls: p<0.001) and 37.1% for HLA-DRB1*1502 (10% in controls: p<0.001). Both alleles were found together as part of a conserved haplotype (52.1AH) at a frequency of 37.1% in patients (8.4% in controls: p<0.001). This is the first description of a haplotypic MHC association with sporadic inclusion body myositis in Japanese patients. These findings indicate that different MHC ancestral haplotypes are associated with sIBM in different ethnic groups and further emphasize the importance of genetic factors in this condition. PMID:16564169

  18. A GWAS SNP for Schizophrenia Is Linked to the Internal MIR137 Promoter and Supports Differential Allele-Specific Expression

    PubMed Central

    Warburton, Alix; Breen, Gerome; Bubb, Vivien J.; Quinn, John P.

    2016-01-01

    Single nucleotide polymorphisms (SNPs) within the MIR137 gene locus have been shown to confer risk for schizophrenia through genome-wide association studies (GWAS). The expression levels of microRNA-137 (miR-137) and its validated gene targets have also been shown to be disrupted in several neuropsychiatric conditions, including schizophrenia. Regulation of miR-137 expression is thus imperative for normal neuronal functioning. We previously characterized an internal promoter domain within the MIR137 gene that contained a variable number tandem repeat (VNTR) polymorphism and could alter the in vitro levels of miR-137 in a stimulus-induced and allele-specific manner. We now demonstrate that haplotype tagging-SNP analysis linked the rs1625579 GWAS SNP for schizophrenia to this internal MIR137 promoter through a proxy SNP rs2660304 located at this domain. We postulated that the rs2660304 promoter SNP may act as predisposing factor for schizophrenia through altering the levels of miR-137 expression in a genotype-dependent manner. Reporter gene analysis of the internal MIR137 promoter containing the common VNTR variant demonstrated genotype-dependent differences in promoter activity with respect to rs2660304. In line with previous reports, the major allele of the rs2660304 proxy SNP, which has previously been linked with schizophrenia risk through genetic association, resulted in downregulation of reporter gene expression in a tissue culture model. The genetic influence of the rs2660304 proxy SNP on the transcriptional activity of the internal MIR137 promoter, and thus the levels of miR-137 expression, therefore offers a distinct regulatory mechanism to explain the functional significance of the rs1625579 GWAS SNP for schizophrenia risk. PMID:26429811

  19. A GWAS SNP for Schizophrenia Is Linked to the Internal MIR137 Promoter and Supports Differential Allele-Specific Expression.

    PubMed

    Warburton, Alix; Breen, Gerome; Bubb, Vivien J; Quinn, John P

    2016-07-01

    Single nucleotide polymorphisms (SNPs) within the MIR137 gene locus have been shown to confer risk for schizophrenia through genome-wide association studies (GWAS). The expression levels of microRNA-137 (miR-137) and its validated gene targets have also been shown to be disrupted in several neuropsychiatric conditions, including schizophrenia. Regulation of miR-137 expression is thus imperative for normal neuronal functioning. We previously characterized an internal promoter domain within the MIR137 gene that contained a variable number tandem repeat (VNTR) polymorphism and could alter the in vitro levels of miR-137 in a stimulus-induced and allele-specific manner. We now demonstrate that haplotype tagging-SNP analysis linked the rs1625579 GWAS SNP for schizophrenia to this internal MIR137 promoter through a proxy SNP rs2660304 located at this domain. We postulated that the rs2660304 promoter SNP may act as predisposing factor for schizophrenia through altering the levels of miR-137 expression in a genotype-dependent manner. Reporter gene analysis of the internal MIR137 promoter containing the common VNTR variant demonstrated genotype-dependent differences in promoter activity with respect to rs2660304. In line with previous reports, the major allele of the rs2660304 proxy SNP, which has previously been linked with schizophrenia risk through genetic association, resulted in downregulation of reporter gene expression in a tissue culture model. The genetic influence of the rs2660304 proxy SNP on the transcriptional activity of the internal MIR137 promoter, and thus the levels of miR-137 expression, therefore offers a distinct regulatory mechanism to explain the functional significance of the rs1625579 GWAS SNP for schizophrenia risk. PMID:26429811

  20. Recovery of Native Genetic Background in Admixed Populations Using Haplotypes, Phenotypes, and Pedigree Information – Using Cika Cattle as a Case Breed

    PubMed Central

    Simčič, Mojca; Smetko, Anamarija; Sölkner, Johann; Seichter, Doris; Gorjanc, Gregor; Kompan, Dragomir; Medugorac, Ivica

    2015-01-01

    The aim of this study was to obtain unbiased estimates of the diversity parameters, the population history, and the degree of admixture in Cika cattle which represents the local admixed breeds at risk of extinction undergoing challenging conservation programs. Genetic analyses were performed on the genome-wide Single Nucleotide Polymorphism (SNP) Illumina Bovine SNP50 array data of 76 Cika animals and 531 animals from 14 reference populations. To obtain unbiased estimates we used short haplotypes spanning four markers instead of single SNPs to avoid an ascertainment bias of the BovineSNP50 array. Genome-wide haplotypes combined with partial pedigree and type trait classification show the potential to improve identification of purebred animals with a low degree of admixture. Phylogenetic analyses demonstrated unique genetic identity of Cika animals. Genetic distance matrix presented by rooted Neighbour-Net suggested long and broad phylogenetic connection between Cika and Pinzgauer. Unsupervised clustering performed by the admixture analysis and two-dimensional presentation of the genetic distances between individuals also suggest Cika is a distinct breed despite being similar in appearance to Pinzgauer. Animals identified as the most purebred could be used as a nucleus for a recovery of the native genetic background in the current admixed population. The results show that local well-adapted strains, which have never been intensively managed and differentiated into specific breeds, exhibit large haplotype diversity. They suggest a conservation and recovery approach that does not rely exclusively on the search for the original native genetic background but rather on the identification and removal of common introgressed haplotypes would be more powerful. Successful implementation of such an approach should be based on combining phenotype, pedigree, and genome-wide haplotype data of the breed of interest and a spectrum of reference breeds which potentially have had

  1. Recovery of native genetic background in admixed populations using haplotypes, phenotypes, and pedigree information--using Cika cattle as a case breed.

    PubMed

    Simčič, Mojca; Smetko, Anamarija; Sölkner, Johann; Seichter, Doris; Gorjanc, Gregor; Kompan, Dragomir; Medugorac, Ivica

    2015-01-01

    The aim of this study was to obtain unbiased estimates of the diversity parameters, the population history, and the degree of admixture in Cika cattle which represents the local admixed breeds at risk of extinction undergoing challenging conservation programs. Genetic analyses were performed on the genome-wide Single Nucleotide Polymorphism (SNP) Illumina Bovine SNP50 array data of 76 Cika animals and 531 animals from 14 reference populations. To obtain unbiased estimates we used short haplotypes spanning four markers instead of single SNPs to avoid an ascertainment bias of the BovineSNP50 array. Genome-wide haplotypes combined with partial pedigree and type trait classification show the potential to improve identification of purebred animals with a low degree of admixture. Phylogenetic analyses demonstrated unique genetic identity of Cika animals. Genetic distance matrix presented by rooted Neighbour-Net suggested long and broad phylogenetic connection between Cika and Pinzgauer. Unsupervised clustering performed by the admixture analysis and two-dimensional presentation of the genetic distances between individuals also suggest Cika is a distinct breed despite being similar in appearance to Pinzgauer. Animals identified as the most purebred could be used as a nucleus for a recovery of the native genetic background in the current admixed population. The results show that local well-adapted strains, which have never been intensively managed and differentiated into specific breeds, exhibit large haplotype diversity. They suggest a conservation and recovery approach that does not rely exclusively on the search for the original native genetic background but rather on the identification and removal of common introgressed haplotypes would be more powerful. Successful implementation of such an approach should be based on combining phenotype, pedigree, and genome-wide haplotype data of the breed of interest and a spectrum of reference breeds which potentially have had

  2. Development of a forensic identity SNP panel for Indonesia.

    PubMed

    Augustinus, Daniel; Gahan, Michelle E; McNevin, Dennis

    2015-07-01

    Genetic markers included in forensic identity panels must exhibit Hardy-Weinberg and linkage equilibrium (HWE and LE). "Universal" panels designed for global use can fail these tests in regional jurisdictions exhibiting high levels of genetic differentiation such as the Indonesian archipelago. This is especially the case where a single DNA database is required for allele frequency estimates to calculate random match probabilities (RMPs) and associated likelihood ratios (LRs). A panel of 65 single nucleotide polymorphisms (SNPs) and a reduced set of 52 SNPs have been selected from 15 Indonesian subpopulations in the HUGO Pan Asian SNP database using a SNP selection strategy that could be applied to any panel of forensic identity markers. The strategy consists of four screening steps: (1) application of a G test for HWE; (2) ranking for high heterozygosity; (3) selection for LE; and (4) selection for low inbreeding depression. SNPs in our Indonesian panel perform well in comparison to some other universal SNP and short tandem repeat (STR) panels as measured by Fisher's exact test for HWE and LE and Wright's F statistics. PMID:25104323

  3. Robust Demographic Inference from Genomic and SNP Data

    PubMed Central

    Excoffier, Laurent; Dupanloup, Isabelle; Huerta-Sánchez, Emilia; Sousa, Vitor C.; Foll, Matthieu

    2013-01-01

    We introduce a flexible and robust simulation-based framework to infer demographic parameters from the site frequency spectrum (SFS) computed on large genomic datasets. We show that our composite-likelihood approach allows one to study evolutionary models of arbitrary complexity, which cannot be tackled by other current likelihood-based methods. For simple scenarios, our approach compares favorably in terms of accuracy and speed with , the current reference in the field, while showing better convergence properties for complex models. We first apply our methodology to non-coding genomic SNP data from four human populations. To infer their demographic history, we compare neutral evolutionary models of increasing complexity, including unsampled populations. We further show the versatility of our framework by extending it to the inference of demographic parameters from SNP chips with known ascertainment, such as that recently released by Affymetrix to study human origins. Whereas previous ways of handling ascertained SNPs were either restricted to a single population or only allowed the inference of divergence time between a pair of populations, our framework can correctly infer parameters of more complex models including the divergence of several populations, bottlenecks and migration. We apply this approach to the reconstruction of African demography using two distinct ascertained human SNP panels studied under two evolutionary models. The two SNP panels lead to globally very similar estimates and confidence intervals, and suggest an ancient divergence (>110 Ky) between Yoruba and San populations. Our methodology appears well suited to the study of complex scenarios from large genomic data sets. PMID:24204310

  4. Family-Based Multi-SNP X Chromosome Analysis Using Parent Information.

    PubMed

    Wise, Alison S; Shi, Min; Weinberg, Clarice R

    2016-01-01

    We propose a method for association analysis of haplotypes on the X chromosome that offers both improved power and robustness to population stratification in studies of affected offspring and their parents if all three have been genotyped. The method makes use of assumed parental haplotype exchangeability (PHE), a weaker assumption than Hardy-Weinberg equilibrium (HWE). PHE requires that in the source population, of the three X chromosome haplotypes carried by the two parents, each is equally likely to be carried by the father. We propose a pseudo-sibling approach that exploits that exchangeability assumption. Our method extends the single-SNP PIX-LRT method to multiple SNPs in a high linkage block. We describe methods for testing the PHE assumption and also for determining how apparent violations can be distinguished from true fetal effects or maternally-mediated effects. We show results of simulations that demonstrate nominal type I error rate and good power. The methods are then applied to dbGaP data on the birth defect oral cleft, using both Asian and Caucasian families with cleft. PMID:26941777

  5. Family-Based Multi-SNP X Chromosome Analysis Using Parent Information

    PubMed Central

    Wise, Alison S.; Shi, Min; Weinberg, Clarice R.

    2016-01-01

    We propose a method for association analysis of haplotypes on the X chromosome that offers both improved power and robustness to population stratification in studies of affected offspring and their parents if all three have been genotyped. The method makes use of assumed parental haplotype exchangeability (PHE), a weaker assumption than Hardy-Weinberg equilibrium (HWE). PHE requires that in the source population, of the three X chromosome haplotypes carried by the two parents, each is equally likely to be carried by the father. We propose a pseudo-sibling approach that exploits that exchangeability assumption. Our method extends the single-SNP PIX-LRT method to multiple SNPs in a high linkage block. We describe methods for testing the PHE assumption and also for determining how apparent violations can be distinguished from true fetal effects or maternally-mediated effects. We show results of simulations that demonstrate nominal type I error rate and good power. The methods are then applied to dbGaP data on the birth defect oral cleft, using both Asian and Caucasian families with cleft. PMID:26941777

  6. Harmful recessive effects on fertility detected by absence of homozygous haplotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Five new lethal recessive defects were discovered in Holsteins, Jerseys, and Brown Swiss by examining haplotypes that had high population frequency but were never homozygous. The method required genotypes only from apparently normal individuals and not from affected embryos. Genotypes from the Bovin...

  7. Effects of Vitamin A and D Receptor Gene Polymorphisms/Haplotypes on Immune Responses to Measles Vaccine

    PubMed Central

    Ovsyannikova, Inna G.; Haralambieva, Iana H.; Vierkant, Robert A.; O’Byrne, Megan M.; Jacobson, Robert M.; Poland, Gregory A.

    2011-01-01

    OBJECTIVE Vitamin A and D, and their receptors, are important regulators of the immune system, including vaccine immune response. We assessed the association between polymorphisms in the vitamin A (RARA, RARB and RARG) and vitamin D receptor (VDR)/RXRA genes and inter-individual variations in immune responses after two doses of measles vaccine in 745 subjects. METHODS Using a tagSNP approach, we genotyped 745 healthy children for the 391 polymorphisms in vitamin A and D receptor genes. RESULTS The RARB haplotype (rs6800566/rs6550976/rs9834818) was significantly associated with variations in both measles antibody (global p=0.013) and cytokine secretion levels, such as IL-10 (global p=0.006), IFN-α (global p=0.008), and TNF-α (global p=0.039) in the Caucasian subgroup. Specifically, the RARB haplotype AAC was associated with higher (t-statistic 3.27, p=0.001) measles antibody levels. At the other end of the spectrum, haplotype GG for rs6550978/rs6777544 was associated with lower antibody levels (t-statistic −2.32, p=0.020) in the Caucasian subgroup. In a sensitivity analysis, the RARB haplotype CTGGGCAA remained marginally significant (p<0.02) when the single SNP rs12630816 was included in the model for IL-10 secretion levels. A significant association was found between lower measles-specific IFN-γ Elispot responses and haplotypes rs11102986/rs11103473/rs11103482/rs10776909/rs12004589/rs35780541/rs2266677/rs875444 (global p=0.004) and rs6537944/rs3118571 (global p<0.001) in the RXRA gene for Caucasians. We also found associations between multiple RARB, VDR and RXRA SNPs/haplotypes and measles-specific IL-2, IL-6, IL-10, IFN-α, IFN-γ, IFNλ-1, and TNF-α cytokine secretion. CONCLUSION Our results suggest that specific allelic variations and haplotypes in the vitamin A and D receptor genes may influence adaptive immune responses to measles vaccine. PMID:22082653

  8. SNP genotyping by DNA photoligation: application to SNP detection of genes from food crops

    NASA Astrophysics Data System (ADS)

    Yoshimura, Yoshinaga; Ohtake, Tomoko; Okada, Hajime; Ami, Takehiro; Tsukaguchi, Tadashi; Fujimoto, Kenzo

    2009-06-01

    We describe a simple and inexpensive single-nucleotide polymorphism (SNP) typing method, using DNA photoligation with 5-carboxyvinyl-2'-deoxyuridine and two fluorophores. This SNP-typing method facilitates qualitative determination of genes from indica and japonica rice, and showed a high degree of single nucleotide specificity up to 10 000. This method can be used in the SNP typing of actual genomic DNA samples from food crops.

  9. The associations of HLA-A, -B, DRB1 alleles and haplotypes in Turkish lymphoma patients.

    PubMed

    Uçar, Fahri; Sönmez, Mehmet; Ermantaş, Nilay; Özbaş, Hasan Mücahit; Cansız, Abide; Balcı, Mustafa; Yılmazz, Mustafa

    2016-07-25

    A significant association between lymphomas and HLA alleles has been shown in previous studies. However, the frequency of HLA alleles and haplotypes has not been studied in Turkish lymphoma patients. We studied HLA-A, -B, -DRB1 alleles and haplotypes in 80 adult lymphomas and 360 unrelated normal subjects by PCR-SSOP method using Luminex technology. The allele frequencies of HLA-A*29, B*07, and DRB1*11 were higher in patients with Hodgkin's lymphoma (HL) compared with the controls [OR; 5.65 (95%CI; 2.16-14.81), P=0.001], [OR; 3.00 (95%CI; 1.50-5.99), P=0.003)], and [OR; 1.80 (95%CI; 1.08-3.01), P=0.002); respectively]. In patients with non-Hodgkin's lymphoma (NHL) HLA-B*51 and DRB1*04 allele frequencies were higher than controls [OR; 2.25 (95%CI; 1.27-4.00), P=0.007] and [OR; 2.14 (95%CI; 1.20-3.78), P=0.01]. The most frequently observed haplotypes were A*02 B*35 DRB1*11 (7.50% vs. 1.89%) in HL patients, A*02 B*51 DRB1*11 (5.00% vs. 1.96%) in NHL patients, and A*02 B*35 DRB1*13 (2.19%) in the controls. We detected four haplotypes specific to NHL, five haplotypes to HL patients. Seven haplotypes were unique to controls. Our findings suggest that in HL patients, HLA-A*29, B*07, and DRB1*11 alleles, and in NHL patients, HLA-B*51 and DRB1*04 alleles might be presumptive predisposing factors. PMID:27063556

  10. Selection at Work in Self-Incompatible Arabidopsis lyrata. II. Spatial Distribution of S Haplotypes in Iceland

    PubMed Central

    Schierup, Mikkel H.; Bechsgaard, Jesper S.; Christiansen, Freddy B.

    2008-01-01

    We survey the distribution of haplotypes at the self-incompatibility (SI) locus of Arabidopsis lyrata (Brassicaceae) at 12 locations spread over the species' natural distribution in Iceland. Previous investigations of the system have identified 34 functionally different S haplotypes maintained by frequency-dependent selection and arranged them into four classes of dominance in their phenotypic expression. On the basis of this model of dominance and the island model of population subdivision, we compare the distribution of S haplotypes with that expected from population genetic theory. We observe 18 different S haplotypes, recessive haplotypes being more common than dominant ones, and dominant ones being shared by fewer populations. As expected, differentiation, although significant, is very low at the S locus even over distances of up to 300 km. The frequency of the most recessive haplotype is slightly larger than expected for a panmictic population, but consistent with a subdivided population with the observed differentiation. Frequencies in nature reflect effects of segregation distortion previously observed in controlled crosses. The dynamics of the S-locus variation are, however, well represented by a 12-island model and our simplified model of dominance interactions. PMID:18780752

  11. SNP Arrays for Species Identification in Salmonids.

    PubMed

    Wenne, Roman; Drywa, Agata; Kent, Matthew; Sundsaasen, Kristil Kindem; Lien, Sigbjørn

    2016-01-01

    The use of SNP genotyping microarrays, developed in one species to analyze a closely related species for which genomic sequence information is scarce, enables the rapid development of a genomic resource (SNP information) without the need to develop new species-specific markers. Using large numbers of microarray SNPs offers the best chance to detect informative markers in nontarget species, markers that can very often be assayed using a lower throughput platform as is described in this paper. PMID:27460372

  12. Genetic variation in the progesterone receptor gene and risk of endometrial cancer: a haplotype-based approach

    PubMed Central

    Lee, Eunjung; Hsu, Chris; Haiman, Christopher A.; Razavi, Pedram; Horn-Ross, Pamela L.; Van Den Berg, David; Bernstein, Leslie; Le Marchand, Loic; Henderson, Brian E.; Setiawan, V. Wendy; Ursin, Giske

    2010-01-01

    Background: It is well established that estrogen increases endometrial cancer risk, whereas progesterone opposes the estrogen effects. The PROGINS allele of the progesterone receptor (PGR) gene reduces the function of PGR and has been associated with increased risk of the endometrioid type ovarian cancer. We investigated whether genetic variation in PGR is also associated with endometrial cancer risk using a haplotype-based approach. Methods: We pooled data from two endometrial cancer case–control studies that were nested within two prospective cohorts, the Multiethnic Cohort Study and the California Teachers Study. Seventeen haplotype-tagging single nucleotide polymorphisms (SNPs) across four linkage disequilibrium (LD) blocks spanning the PGR locus were genotyped in 583 incident cases and 1936 control women. Odds ratios (ORs) and 95% confidence intervals (CIs) associated with each haplotype were estimated using conditional logistic regression, stratified by age and ethnicity. Results: Genetic variation in LD block 3 of the PGR locus was associated with endometrial cancer risk (Pglobal test = 0.002), with haplotypes 3C, 3D and 3F associated with 31–34% increased risk. Among whites (383 cases/840 controls), genetic variation in all four blocks was associated with increased endometrial cancer risk (Pglobal test = 0.010, 0.013, 0.005 and 0.020). Haplotypes containing the PROGINS allele and several haplotypes in blocks 1, 3 and 4 were associated with 34–77% increased risk among whites. SNP analyses for whites suggested that rs608995, partially linked to the PROGINS allele (r2 = 0.6), was associated with increased risk (OR = 1.30, 95% CI = 1.06–1.59). Conclusions: Our results suggest that genetic variation in the PGR region is associated with endometrial cancer risk. PMID:20547493

  13. Phospholipase C epsilon 1 (PLCE1) Haplotypes are Associated with Increased Risk of Gastric Cancer in Kashmir Valley

    PubMed Central

    Malik, Manzoor A.; Srivastava, Priya; Zargar, Showkat A.; Mittal, Balraj

    2014-01-01

    Background/Aim: Phospholipase C epsilon 1 (PLCE1) plays a crucial role in carcinogenesis and progression of several types of cancers. A single nucleotide polymorphism (SNP, rs2274223) in PLCE1 has been identified as a novel susceptibility locus. The aim of the present study was to investigate the role of three potentially functional SNPs (rs2274223A > G, rs3765524C > T, and rs7922612C > T) of PLCE1 in gastric cancer patients from Kashmir Valley. Patients and Methods: The study was conducted in 108 GC cases and 195 healthy controls from Kashmir Valley. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism method. Data were statistically analyzed using χ2 test and logistic regression models. A P value of less than 0.05 was regarded as statistically significant. Results: The frequency of PLCE1 A2274223C3765524T7922612, G2274223C3765524T7922612, and G2274223T3765524C7922612 haplotypes were higher in patients compared with controls, conferred high risk for GC [odds ratio (OR) =6.29; P = 0.001; Pcorr = 0.003], (OR = 3.23; P = 0.011; Pcorr = 0.033), and (OR = 5.14; P = 0.011; Pcorr = 0.033), respectively. Smoking and salted tea are independent risk factors for GC, but we did not find any significant modulation of cancer risk by PLCE1 variants with smoking or excessive consumption of salted tea. Conclusion: These results suggest that variation in PLCE1 may be associated with GC risk in Kashmir Valley. PMID:25434319

  14. PEAS V1.0: a package for elementary analysis of SNP data.

    PubMed

    Xu, Shuhua; Gupta, Sanchit; Jin, Li

    2010-11-01

    We have developed a software package named PEAS to facilitate analyses of large data sets of single nucleotide polymorphisms (SNPs) for population genetics and molecular phylogenetics studies. PEAS reads SNP data in various formats as input and is versatile in data formatting; using PEAS, it is easy to create input files for many popular packages, such as STRUCTURE, frappe, Arlequin, Haploview, LDhat, PLINK, EIGENSOFT, PHASE, fastPHASE, MEGA and PHYLIP. In addition, PEAS fills up several analysis gaps in currently available computer programs in population genetics and molecular phylogenetics. Notably, (i) It calculates genetic distance matrices with bootstrapping for both individuals and populations from genome-wide high-density SNP data, and the output can be streamlined to MEGA and PHYLIP programs for further processing; (ii) It calculates genetic distances from STRUCTURE output and generates MEGA file to reconstruct component trees; (iii) It provides tools to conduct haplotype sharing analysis for phylogenetic studies based on high-density SNP data. To our knowledge, these analyses are not available in any other computer program. PEAS for Windows is freely available for academic users from http://www.picb.ac.cn/~xushua/index.files/Download_PEAS.htm. PMID:21565121

  15. Leukotriene A4 Hydrolase Haplotype, Diet and Atherosclerosis: A Twin Study

    PubMed Central

    Zhao, Jinying; Goldberg, Jack; Vaccarino, Viola

    2012-01-01

    Objective Atherosclerosis is an inflammatory process resulting from the interaction between genetic and environmental factors. Leukotrienes are inflammatory mediators generated from arachidonic acid, and genetic polymorphisms involved in leukotriene metabolism are implicated in atherosclerosis. The objectives of this study are to examine whether genetic variants in key leukotriene enzymes are associated with atherosclerosis, and whether dietary intake of competing leukotriene substrates modifies the effect of leukotriene variants on atherosclerosis. Methods Atherosclerosis was assessed by common carotid intima-media thickness (IMT) using ultrasound. Sequence variants within arachidonate 5-lipoxygenase activating protein (ALOX5AP) and leukotriene A4 hydrolase (LTA4H) genes were analyzed with 32 single nucleotide polymorphisms (SNPs) in 169 Caucasian twin pairs from the Vietnam Era Twin Registry. The associations between genetic polymorphisms and carotid atherosclerosis, and gene × diet interactions were examined by generalized estimating equation controlling for potential confounders. Results A six-SNP haplotype in LTA4H, designated HapE, was significantly associated with carotid IMT after adjusting for known coronary risk factors. Twins carrying HapE had a much lower IMT compared to twins not carrying (695 μm vs. 750 μm, p=0.0007). Moreover, dietary intake of polyunsaturated fatty acids strongly augmented the cardioprotective effect of HapE among those with this haplotype but not those without, suggesting a haplotype × diet interaction (Interaction PHapE × n-3 = 0.03, PHapE × n-6 = 0.015). Conclusion We identified a novel leukotriene haplotype that appears to be protective towards subclinical atherosclerosis. This association is modified by dietary intake of polyunsaturated fatty acids. PMID:23153620

  16. Evaluation of approaches for identifying population informative markers from high density SNP Chips

    PubMed Central

    2011-01-01

    Background Genetic markers can be used to identify and verify the origin of individuals. Motivation for the inference of ancestry ranges from conservation genetics to forensic analysis. High density assays featuring Single Nucleotide Polymorphism (SNP) markers can be exploited to create a reduced panel containing the most informative markers for these purposes. The objectives of this study were to evaluate methods of marker selection and determine the minimum number of markers from the BovineSNP50 BeadChip required to verify the origin of individuals in European cattle breeds. Delta, Wright's FST, Weir & Cockerham's FST and PCA methods for population differentiation were compared. The level of informativeness of each SNP was estimated from the breed specific allele frequencies. Individual assignment analysis was performed using the ranked informative markers. Stringency levels were applied by log-likelihood ratio to assess the confidence of the assignment test. Results A 95% assignment success rate for the 384 individually genotyped animals was achieved with < 80, < 100, < 140 and < 200 SNP markers (with increasing stringency threshold levels) across all the examined methods for marker selection. No further gain in power of assignment was achieved by sampling in excess of 200 SNP markers. The marker selection method that required the lowest number of SNP markers to verify the animal's breed origin was Wright's FST (60 to 140 SNPs depending on the chosen degree of confidence). Certain breeds required fewer markers (< 100) to achieve 100% assignment success. In contrast, closely related breeds require more markers (~200) to achieve > 95% assignment success. The power of assignment success, and therefore the number of SNP markers required, is dependent on the levels of genetic heterogeneity and pool of samples considered. Conclusions While all SNP selection methods produced marker panels capable of breed identification, the power of assignment varied markedly among

  17. Spatial and temporal distribution of the neutral polymorphisms in the last ZFX intron: analysis of the haplotype structure and genealogy.

    PubMed Central

    Jaruzelska, J; Zietkiewicz, E; Batzer, M; Cole, D E; Moisan, J P; Scozzari, R; Tavaré, S; Labuda, D

    1999-01-01

    With 10 segregating sites (simple nucleotide polymorphisms) in the last intron (1089 bp) of the ZFX gene we have observed 11 haplotypes in 336 chromosomes representing a worldwide array of 15 human populations. Two haplotypes representing 77% of all chromosomes were distributed almost evenly among four continents. Five of the remaining haplotypes were detected in Africa and 4 others were restricted to Eurasia and the Americas. Using the information about the ancestral state of the segregating positions (inferred from human-great ape comparisons), we applied coalescent analysis to estimate the age of the polymorphisms and the resulting haplotypes. The oldest haplotype, with the ancestral alleles at all the sites, was observed at low frequency only in two groups of African origin. Its estimated age of 740 to 1100 kyr corresponded to the time to the most recent common ancestor. The two most frequent worldwide distributed haplotypes were estimated at 550 to 840 and 260 to 400 kyr, respectively, while the age of the continentally restricted polymorphisms was 120 to 180 kyr and smaller. Comparison of spatial and temporal distribution of the ZFX haplotypes suggests that modern humans diverged from the common ancestral stock in the Middle Paleolithic era. Subsequent range expansion prevented substantial gene flow among continents, separating African groups from populations that colonized Eurasia and the New World. PMID:10388827

  18. Spatial and temporal distribution of the neutral polymorphisms in the last ZFX intron: analysis of the haplotype structure and genealogy.

    PubMed

    Jaruzelska, J; Zietkiewicz, E; Batzer, M; Cole, D E; Moisan, J P; Scozzari, R; Tavaré, S; Labuda, D

    1999-07-01

    With 10 segregating sites (simple nucleotide polymorphisms) in the last intron (1089 bp) of the ZFX gene we have observed 11 haplotypes in 336 chromosomes representing a worldwide array of 15 human populations. Two haplotypes representing 77% of all chromosomes were distributed almost evenly among four continents. Five of the remaining haplotypes were detected in Africa and 4 others were restricted to Eurasia and the Americas. Using the information about the ancestral state of the segregating positions (inferred from human-great ape comparisons), we applied coalescent analysis to estimate the age of the polymorphisms and the resulting haplotypes. The oldest haplotype, with the ancestral alleles at all the sites, was observed at low frequency only in two groups of African origin. Its estimated age of 740 to 1100 kyr corresponded to the time to the most recent common ancestor. The two most frequent worldwide distributed haplotypes were estimated at 550 to 840 and 260 to 400 kyr, respectively, while the age of the continentally restricted polymorphisms was 120 to 180 kyr and smaller. Comparison of spatial and temporal distribution of the ZFX haplotypes suggests that modern humans diverged from the common ancestral stock in the Middle Paleolithic era. Subsequent range expansion prevented substantial gene flow among continents, separating African groups from populations that colonized Eurasia and the New World. PMID:10388827

  19. Genetic stock structure of walleye pollock (Theragra chalcogramma) inferred by PCR-RFLP analysis of the mitochondrial DNA and SNP analysis of nuclear DNA.

    PubMed

    Yanagimoto, Takashi; Kitamura, Toru; Kobayashi, Takanori

    2012-09-01

    Walleye pollock, Theragra chalocogramma, is one of the most important species in the North Pacific and Bering Sea ecosystems. However genetic population structuring of walleye pollock is uncertain. In the present study, genetic variation of walleye pollock collected in several spawning areas ranging from the Japan Sea to the Gulf of Alaska was investigated by DNA analysis. Three regions of the spacer control region, the ND5 and ND6 region (ND complex), and the ND1 and 16S rRNA region (rDNA complex) were amplified using the polymerase chain reaction (PCR). Restriction fragment length polymorphism (RFLP) was conducted on these PCR products and composite haplotypes were calculated. Furthermore, several nuclear DNA regions (actin, Calmodulin, S7 ribosomal protein, creatin kinase, and SypI gene) were investigated to study the stock structure of walleye pollock. It was considered that Calmodulin gene was one of good genetic marker, therefore we conducted SNP analysis for Calmodulin gene by SnaPshot kits. In RFLP analyses, there were no area-specific fragment patterns in the three regions, control region, ND complex and rDNA complex of mtDNA. However compositions of the fragment patterns for the three digested sets, control region/HinfI, rDNA complex/MspI and ND complex/MspI indicated that there are significant differences between around the Japan (Sado-Funka Bay-Wakkanai-Rausu) and the Bering Sea (Western Bering Sea-Nabarin-Atka I.-Bogoslof I). Furthermore, in the case of haplotype frequency, composition showed also significant genetic difference between two areas. Moreover, in Calmodulin analyses, haplotype compositions were changing from western area to eastern area gradually and the results of AMOVA analysis showed that there are interesting differences between western Pacific, western Bering Sea, and eastern Bering Sea. Judging from these results, it was considered that there are three populations of walleye pollock in the Northern Ocean. However, area

  20. Mother-child HLA compatibility ratios in children of Amerinidian parents who share common haplotypes.

    PubMed Central

    Black, F L

    1985-01-01

    Among 166 children whose parents share the HLA-A, -B, and -C antigens of at least one haplotype, there is a superficial concordance between observed and expected proportions of children whose mothers would recognize no foreign antigen in them. However, this balance is composed of fewer (64%) homozygous offspring than expected and more (147%) than the expected number of genotypes identical to the mother's. A homozygous child would be expected to recognize his or her mother as foreign, unless the mother was also homozygous, but an HLA-identical child would not. Thus, the number of children who might be immunologically tolerant of their mothers was greater than expected. No one of the three loci included in designating haplotypes was individually responsible for the divergences in haplotype frequency. PMID:3976655

  1. Genetic polymorphisms for 17 Y-chromosomal STR haplotypes in Jammu and Kashmir Saraswat Brahmin population.

    PubMed

    Yadav, Bhuvnesh; Raina, Anupuma; Dogra, Tirath Das

    2010-09-01

    In this study 17 Y-chromosomal STRs (including DYS19, DYS389I, DS389II, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and Y GATA H4) were analysed using blood samples of 122 unrelated male individuals belonging to Saraswat Brahmin community from Jammu (ID YP000599) and Kashmir (ID YP000600) region of J&K state of India. The allelic frequency distribution and haplotype diversity of 17 Y-chromosomal STR for both the populations were calculated. In the Kashmiri Saraswat group, a total of 109 haplotypes were identified in 122 individuals, of these haplotypes, 101 were found only once. The gene diversity values of STR loci ranged from 0.4813 (DYS391) to 0.8645 (DYS385a/b) for Jammu & Kashmiri Saraswat Brahmins. PMID:20621539

  2. Haplotype diversity of 17 Y-chromosomal STRs in Saraswat Brahmin Community of North India.

    PubMed

    Yadav, Bhuvnesh; Raina, Anupuma; Dogra, Tirath Das

    2011-06-01

    In this study, 17 Y-specific STR loci (DYS19, DYS389I, DS389II, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and Y_GATA_H4) were analyzed in 181 unrelated male individuals from three North Indian states. A total of 157 different 17-loci haplotypes were identified, 145 of which were unique. The most frequent haplotype was detected in nine instances, occurring with a frequency of 4.97%. These results, including the haplotype data at 17 Y-STR loci in the present study, provide useful information for forensic practice in the Saraswat Brahmin population in North India. PMID:20971692

  3. 17 Y-STR haplotype data for a population sample of Residents in the Basque Country.

    PubMed

    Valverde, Laura; Köhnemann, Stephan; Rosique, Melania; Cardoso, Sergio; Zarrabeitia, Maite; Pfeiffer, Heidi; de Pancorbo, Marian M

    2012-07-01

    Non autochthonous population is the most numerous group in the Basque Country. This group is named "Residents" to distinguish them from the "Autochthonous Basque" population. In this work, the 17 Y-STR loci distribution of Resident population was studied in a sample of 197 individuals, who were concretely genotyped for DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS439, DYS438, DYS437, DYS448, DYS456, DYS458, DYS635 and Y GATA H4. Resident population showed a high haplotype diversity and discrimination capacity. The distribution of Y-STRs haplotypes of the Resident population was statistically significant different to the one of the Autochthonous Basque population. The genetic substructure found between Resident and Autochthonous Basque 17 Y-STR haplotype distributions advises for the use of two different databases in the Basque Country, to ensure the most trustworthy frequency estimate in casework. PMID:22342392

  4. Haplotype diversity of 17 Y-str loci in an admixed population from the Brazilian Amazon

    PubMed Central

    Francez, Pablo Abdon da Costa; Ramos, Luiz Patrick Vidal; de Jesus Brabo Ferreira Palha, Teresinha; dos Santos, Sidney Emanuel Batista

    2012-01-01

    The allelic and haplotype frequencies of 17 Y-STR loci most commonly used in forensic testing were estimated in a sample of 138 unrelated healthy males from Macapá, in the northern Amazon region of Brazil. The average gene diversity was 0.6554 ± 0.3315. 134 haplotypes of the 17 loci were observed, 130 of them unique and four present in two individuals each. The haplotype diversity index was 0.9996 + 0.0009, with the most frequent haplogroups being R1b (52.2%), E1b1b (11.6%), J2 (10.1%) and Q (7.2%). Most haplogroups of this population belonged to European male lineages (89.2%), followed by Amerindian (7.2%) and African (3.6%) lineages. PMID:22481873

  5. Evolution of the mouse t haplotype: recent and worldwide introgression to Mus musculus.

    PubMed Central

    Morita, T; Kubota, H; Murata, K; Nozaki, M; Delarbre, C; Willison, K; Satta, Y; Sakaizumi, M; Takahata, N; Gachelin, G

    1992-01-01

    Mouse t haplotypes are variants of chromosome 17, consisting of four inversions. Despite the homozygous lethality and pleiotropic effect on embryonic development, sperm production, and recombination, they have widely spread in natural populations of the house mouse (10-40% in frequency) because of the meiotic drive advantage. We sequenced 14 Tcp-1 (t-complex polypeptide 1) genes from four t haplotypes, nine wild mice, and a rat as a reference. From a comparison of intron sequences of 610 base pairs, we dated the origin of t haplotypes to 2.9 +/- 0.7 million years ago, which predates the splitting of Mus musculus subspecies (approximately 1 million years ago). However, the Tcp-1 intron sequences of t haplotypes from different M. musculus subspecies from various parts of the world show no divergence, indicating the recent introgression (no earlier than 0.8 million years ago) of a single ancestral type. Nucleotide changes in coding regions are also consistent with this conclusion. Hence, polymorphisms among t haplotypes including lethality factors have accumulated during this short time period independently in each M. musculus subspecies. PMID:1495973

  6. PADI4 Haplotypes in Association with RA Mexican Patients, a New Prospect for Antigen Modulation

    PubMed Central

    Gonzalez-Montoya, Norma Guadalupe; Gamez-Nava, Jorge I.; Moran-Moguel, Maria Cristina; Rosales-Gomez, Roberto Carlos; Gutierrez-Rubio, Susan Andrea; Sanchez-Corona, Jose; Davalos-Rodriguez, Ingrid Patricia; Salazar-Paramo, Mario

    2013-01-01

    Peptidyl arginine deiminase IV (PAD 4) is the responsible enzyme for a posttranslational modification called citrullination, originating the antigenic determinant recognized by anti-cyclic citrullinated peptide antibodies (ACPA). Four SNPs (single nucleotide polymorphisms) have been described in PADI4 gene to form a susceptibility haplotype for rheumatoid arthritis (RA); nevertheless, results in association studies appear contradictory in different populations. The aim of the study was to analyze if the presence of three SNPs in PADI4 gene susceptibility haplotype (GTG) is associated with ACPA positivity in patients with RA. This was a cross-sectional study that included 86 RA patients and 98 healthy controls. Polymorphisms PADI4_89, PADI4_90, and PADI4_92 in the PADI4 gene were genotyped. The susceptibility haplotype (GTG) was more frequent in RA patients; interestingly, we found a new haplotype associated with RA with a higher frequency (GTC). There were no associations between polymorphisms and high scores in Spanish HAQ-DI and DAS-28, but we did find an association between RARBIS index and PADI4_89, PADI4_90 polymorphisms. We could not confirm an association between susceptibility haplotype presence and ACPA positivity. Further evidence about proteomic expression of this gene will determine its participation in antigenic generation and autoimmunity. PMID:24454473

  7. PADI4 haplotypes in association with RA Mexican patients, a new prospect for antigen modulation.

    PubMed

    Zavala-Cerna, Maria Guadalupe; Gonzalez-Montoya, Norma Guadalupe; Nava, Arnulfo; Gamez-Nava, Jorge I; Moran-Moguel, Maria Cristina; Rosales-Gomez, Roberto Carlos; Gutierrez-Rubio, Susan Andrea; Sanchez-Corona, Jose; Gonzalez-Lopez, Laura; Davalos-Rodriguez, Ingrid Patricia; Salazar-Paramo, Mario

    2013-01-01

    Peptidyl arginine deiminase IV (PAD 4) is the responsible enzyme for a posttranslational modification called citrullination, originating the antigenic determinant recognized by anti-cyclic citrullinated peptide antibodies (ACPA). Four SNPs (single nucleotide polymorphisms) have been described in PADI4 gene to form a susceptibility haplotype for rheumatoid arthritis (RA); nevertheless, results in association studies appear contradictory in different populations. The aim of the study was to analyze if the presence of three SNPs in PADI4 gene susceptibility haplotype (GTG) is associated with ACPA positivity in patients with RA. This was a cross-sectional study that included 86 RA patients and 98 healthy controls. Polymorphisms PADI4_89, PADI4_90, and PADI4_92 in the PADI4 gene were genotyped. The susceptibility haplotype (GTG) was more frequent in RA patients; interestingly, we found a new haplotype associated with RA with a higher frequency (GTC). There were no associations between polymorphisms and high scores in Spanish HAQ-DI and DAS-28, but we did find an association between RARBIS index and PADI4_89, PADI4_90 polymorphisms. We could not confirm an association between susceptibility haplotype presence and ACPA positivity. Further evidence about proteomic expression of this gene will determine its participation in antigenic generation and autoimmunity. PMID:24454473

  8. Haplotypes in the Dystrophin DNA Segment Point to a Mosaic Origin of Modern Human Diversity

    PubMed Central

    Ziętkiewicz, Ewa; Yotova, Vania; Gehl, Dominik; Wambach, Tina; Arrieta, Isabel; Batzer, Mark; Cole, David E. C.; Hechtman, Peter; Kaplan, Feige; Modiano, David; Moisan, Jean-Paul; Michalski, Roman; Labuda, Damian

    2003-01-01

    Although Africa has played a central role in human evolutionary history, certain studies have suggested that not all contemporary human genetic diversity is of recent African origin. We investigated 35 simple polymorphic sites and one Tn microsatellite in an 8-kb segment of the dystrophin gene. We found 86 haplotypes in 1,343 chromosomes from around the world. Although a classical out-of-Africa topology was observed in trees based on the variant frequencies, the tree of haplotype sequences reveals three lineages accounting for present-day diversity. The proportion of new recombinants and the diversity of the Tn microsatellite were used to estimate the age of haplotype lineages and the time of colonization events. The lineage that underwent the great expansion originated in Africa prior to the Upper Paleolithic (27,000–56,000 years ago). A second group, of structurally distinct haplotypes that occupy a central position on the tree, has never left Africa. The third lineage is represented by the haplotype that lies closest to the root, is virtually absent in Africa, and appears older than the recent out-of-Africa expansion. We propose that this lineage could have left Africa before the expansion (as early as 160,000 years ago) and admixed, outside of Africa, with the expanding lineage. Contemporary human diversity, although dominated by the recently expanded African lineage, thus represents a mosaic of different contributions. PMID:14513410

  9. Haplotype and diplotype analyses of variation in ERCC5 transcription cis-regulation in normal bronchial epithelial cells.

    PubMed

    Zhang, Xiaolu; Crawford, Erin L; Blomquist, Thomas M; Khuder, Sadik A; Yeo, Jiyoun; Levin, Albert M; Willey, James C

    2016-07-01

    Excision repair cross-complementation group 5 (ERCC5) gene plays an important role in nucleotide excision repair, and dysregulation of ERCC5 is associated with increased lung cancer risk. Haplotype and diplotype analyses were conducted in normal bronchial epithelial cells (NBEC) to better understand mechanisms responsible for interindividual variation in transcript abundance regulation of ERCC5 We determined genotypes at putative ERCC5 cis-regulatory SNPs (cis-rSNP) rs751402 and rs2296147, and marker SNPs rs1047768 and rs17655. ERCC5 allele-specific transcript abundance was assessed by a recently developed targeted sequencing method. Syntenic relationships among alleles at rs751402, rs2296147, and rs1047768 were assessed by allele-specific PCR followed by Sanger sequencing. We then assessed association of ERCC5 allele-specific expression at rs1047768 with haplotype and diplotype structure at cis-rSNPs rs751402 and rs2296147. Genotype analysis revealed significantly (P < 0.005) higher interindividual variation in allelic ratios in cDNA samples relative to matched gDNA samples at both rs1047768 and rs17655. By diplotype analysis, mean expression was higher at the rs1047768 alleles syntenic with rs2296147 T allele compared with rs2296147 C allele. Furthermore, mean expression was lower at rs17655 C allele, which is syntenic with G allele at a linked SNP rs873601 (D' = 0.95). These data support the conclusions that in NBEC, T allele at SNP rs2296147 upregulates ERCC5, variation at rs751402 does not alter ERCC5 regulation, and that C allele at SNP rs17655 downregulates ERCC5 Variation in ERCC5 transcript abundance associated with allelic variation at these SNPs could result in variation in NER function in NBEC and lung cancer risk. PMID:27235448

  10. Development of SNP markers for genes of the phenylpropanoid pathway and their association to kernel and malting traits in barley

    PubMed Central

    2013-01-01

    Background Flavonoids are an important class of secondary compounds in angiosperms. Next to certain biological functions in plants, they play a role in the brewing process and have an effect on taste, color and aroma of beer. The aim of this study was to reveal the haplotype diversity of candidate genes involved in the phenylpropanoid biosynthesis pathway in cultivated barley varieties (Hordeum vulgare L.) and to determine associations to kernel and malting quality parameters. Results Five genes encoding phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), chalcone synthase (CHS), flavanone 3-hydroxylase (F3H) and dihydroflavonol reductase (DFR) of the phenylpropanoid biosynthesis pathway were partially resequenced in 16 diverse barley reference genotypes. Their localization in the barley genome, their genetic structure, and their genetic variation e.g. single nucleotide polymorphism (SNP) and Insertion/Deletion (InDel) patterns were revealed. In total, 130 SNPs and seven InDels were detected. Of these, 21 polymorphisms were converted into high-throughput pyrosequencing markers. The resulting SNP and haplotype patterns were used to calculate associations with kernel and malting quality parameters. Conclusions SNP patterns were found to be highly variable for the investigated genes. The developed high-throughput markers are applicable for assessing the genetic variability and for the determination of haplotype patterns in a set of barley accessions. The candidate genes PAL, C4H and F3H were shown to be associated to several malting properties like glassiness (PAL), viscosity (C4H) or to final attenuation (F3H). PMID:24088365

  11. Genome-wide SNP detection, validation, and development of an 8K SNP array for apple

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As high-throughput genetic marker screening systems are essential for a range of genetics studies and plant breeding applications, the International RosBREED SNP Consortium (IRSC) has utilized the Illumina Infinium® II system to develop a medium- to high-throughput SNP screening tool for genome-wide...

  12. SNPMeta: SNP annotation and SNP metadata collection without a reference genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The increase in availability of resequencing data is greatly accelerating SNP discovery and has facilitated the development of SNP genotyping assays. This, in turn, is increasing interest in annotation of individual SNPs. Currently, these data are only available through curation, or comparison to a ...

  13. A SNP discovery method to assess variant allele probability from next-generation resequencing data

    PubMed Central

    Shen, Yufeng; Wan, Zhengzheng; Coarfa, Cristian; Drabek, Rafal; Chen, Lei; Ostrowski, Elizabeth A.; Liu, Yue; Weinstock, George M.; Wheeler, David A.; Gibbs, Richard A.; Yu, Fuli

    2010-01-01

    Accurate identification of genetic variants from next-generation sequencing (NGS) data is essential for immediate large-scale genomic endeavors such as the 1000 Genomes Project, and is crucial for further genetic analysis based on the discoveries. The key challenge in single nucleotide polymorphism (SNP) discovery is to distinguish true individual variants (occurring at a low frequency) from sequencing errors (often occurring at frequencies orders of magnitude higher). Therefore, knowledge of the error probabilities of base calls is essential. We have developed Atlas-SNP2, a computational tool that detects and accounts for systematic sequencing errors caused by context-related variables in a logistic regression model learned from training data sets. Subsequently, it estimates the posterior error probability for each substitution through a Bayesian formula that integrates prior knowledge of the overall sequencing error probability and the estimated SNP rate with the results from the logistic regression model for the given substitutions. The estimated posterior SNP probability can be used to distinguish true SNPs from sequencing errors. Validation results show that Atlas-SNP2 achieves a false-positive rate of lower than 10%, with an ∼5% or lower false-negative rate. PMID:20019143

  14. An Arabidopsis haplotype map takes root

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laying the foundation for an A. thaliana haplotype map, Clark et al.1 conducted a thorough array resequencing of 20 diverse A. thaliana genomes at single-base resolution. This provided a powerful catalog of genetic diversity, with more than 1 million SNPs and hypervariable regions (50-bp to >10-kb d...

  15. Applications of haplotypes in dairy farm management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Haplotypes from genomic tests are now available for almost 100,000 dairy cows and heifers in the U.S.. Genomic EBV values are accelerating the rate of genetic improvement in dairy cattle, but genomic information also is useful for making improved decisions on the farm. Mate selection strategies have...

  16. Dissecting risk haplotypes in sporadic Alzheimer's disease.

    PubMed

    Soldner, Frank; Jaenisch, Rudolf

    2015-04-01

    Understanding how genetic risk variants contribute to complex diseases is crucial for predicting disease susceptibility and developing patient-tailored therapies. In this issue of Cell Stem Cell, Young et al. (2015) dissect the function of common non-coding risk haplotypes in the SORL1 locus in the pathogenesis of sporadic Alzheimer's disease using patient-derived induced pluripotent stem cells. PMID:25842969

  17. Association of hypothyroid disease in Doberman Pinscher dogs with a rare major histocompatibility complex DLA class II haplotype.

    PubMed

    Kennedy, L J; Huson, H J; Leonard, J; Angles, J M; Fox, L E; Wojciechowski, J W; Yuncker, C; Happ, G M

    2006-01-01

    Canine hypothyroid disease is similar to Hashimoto's disease in humans, which has been shown to be associated with human major histocompatibility complex (MHC) genes. We have collected 27 Doberman Pinschers affected with primary hypothyroid disease and compared their MHC class II haplotypes with 129 unaffected Doberman Pinschers. Three dog-leucocyte antigen (DLA) genes, DLA-DRB1, DQA1 and DQB1, were characterized by sequence-based typing and assigned to haplotypes for each dog. One rare haplotype was found at an increased frequency in the affected dogs compared to the unaffected dogs (Odds ratio = 2.43, P < 0.02). This haplotype has only been found in Doberman Pinschers and Labradors to date. PMID:16451201

  18. Addiction Genetics and Pleiotropic Effects of Common Haplotypes that Make Polygenic Contributions to Vulnerability to Substance Dependence

    PubMed Central

    Uhl, George R.; Drgon, Tomas; Johnson, Catherine; Liu, Qing-Rong

    2016-01-01

    Abundant evidence from family, adoption, and twin studies point to large genetic contributions to individual differences in vulnerability to develop dependence on one or more addictive substances. Twin data suggest that most of this genetic vulnerability is shared by individuals who are dependent on a variety of addictive substances. Molecular genetic studies, especially genomewide and candidate gene association studies, have elucidated common haplotypes in dozens of genes that appear to make polygenic contributions to vulnerability to developing dependence. Most genes that harbor currently identified addiction-associated haplotypes are expressed in the brain. Haplotypes in many of the same genes are identified in genomewide association studies that compare allele frequencies in substance dependent vs. control individuals from European, African, and Asian racial/ethnic backgrounds. Many of these addiction-associated haplotypes display pleiotropic influences on a variety of related brain-based phenotypes that display 1) substantial heritability and 2) clinical cooccurence with substance dependence. PMID:19152208

  19. SNP Discovery Using Next Generation Transcriptomic Sequencing.

    PubMed

    De Wit, Pierre

    2016-01-01

    In this chapter, I will guide the user through methods to find new SNP markers from expressed sequence (RNA-Seq) data, focusing on the sample preparation and also on the bioinformatic analyses needed to sort through the immense flood of data from high-throughput sequencing machines. The general steps included are as follows: sample preparation, sequencing, quality control of data, assembly, mapping, SNP discovery, filtering, validation. The first few steps are traditional laboratory protocols, whereas steps following the sequencing are of bioinformatic nature. The bioinformatics described herein are by no means exhaustive, rather they serve as one example of a simple way of analyzing high-throughput sequence data to find SNP markers. Ideally, one would like to run through this protocol several times with a new dataset, while varying software parameters slightly, in order to determine the robustness of the results. The final validation step, although not described in much detail here, is also quite critical as that will be the final test of the accuracy of the assumptions made in silico.There is a plethora of downstream applications of a SNP dataset, not covered in this chapter. For an example of a more thorough protocol also including differential gene expression and functional enrichment analyses, BLAST annotation and downstream applications of SNP markers, a good starting point could be the "Simple Fool's Guide to population genomics via RNA-Seq," which is available at http://sfg.stanford.edu . PMID:27460371

  20. Haplotypes and Sequence Variation in the Ovine Adiponectin Gene (ADIPOQ)

    PubMed Central

    An, Qing-Ming; Zhou, Hui-Tong; Hu, Jiang; Luo, Yu-Zhu; Hickford, Jon G. H.

    2015-01-01

    The adiponectin gene (ADIPOQ) plays an important role in energy homeostasis. In this study five separate regions (regions 1 to 5) of ovine ADIPOQ were analysed using PCR-SSCP. Four different PCR-SSCP patterns (A1-D1, A2-D2) were detected in region-1 and region-2, respectively, with seven and six SNPs being revealed. In region-3, three different patterns (A3-C3) and three SNPs were observed. Two patterns (A4-B4, A5-B5) and two and one SNPs were observed in region-4 and region-5, respectively. In total, nineteen SNPs were detected, with five of them in the coding region and two (c.46T/C and c.515G/A) putatively resulting in amino acid changes (p.Tyr16His and p.Lys172Arg). In region-1, -2 and -3 of 316 sheep from eight New Zealand breeds, variants A1, A2 and A3 were the most common, although variant frequencies differed in the eight breeds. Across region-1 and region-3, nine haplotypes were identified and haplotypes A1-A3, A1-C3, B1-A3 and B1-C3 were most common. These results indicate that the ADIPOQ gene is polymorphic and suggest that further analysis is required to see if the variation in the gene is associated with animal production traits. PMID:26610572

  1. selectSNP – An R package for selecting SNPs optimal for genetic evaluation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There has been a huge increase in the number of SNPs in the public repositories. This has made it a challenge to design low and medium density SNP panels, which requires careful selection of available SNPs considering many criteria, such as map position, allelic frequency, possible biological functi...

  2. Geostatistical inference of main Y-STR-haplotype groups in Europe.

    PubMed

    Diaz-Lacava, Amalia; Walier, Maja; Willuweit, Sascha; Wienker, Thomas F; Fimmers, Rolf; Baur, Max P; Roewer, Lutz

    2011-03-01

    We examined the multifarious genetic heterogeneity of Europe and neighboring regions from a geographical perspective. We created composite maps outlining the estimated geographical distribution of major groups of genetically similar individuals on the basis of forensic Y-chromosomal markers. We analyzed Y-chromosomal haplotypes composed of 7 highly polymorphic STR loci, genotyped for 33,010 samples, collected at 249 sites in Europe, Western Asia and North Africa, deposited in the YHRD database (www.yhrd.org). The data set comprised 4176 different haplotypes, which we grouped into 20 clusters. For each cluster, the frequency per site was calculated. All geostatistical analysis was performed with the geographic information system GRASS-GIS. We interpolated frequency values across the study area separately for each cluster. Juxtaposing all 20 interpolated surfaces, we point-wisely screened for the highest cluster frequencies and stored it in parallel with the respective cluster label. We combined these two types of data in a composite map. We repeated this procedure for the second highest frequencies in Europe. Major groups were assigned to Northern, Western and Eastern Europe. North Africa built a separate region, Southeastern Europe, Turkey and Near East were divided into several regions. The spatial distribution of the groups accounting for the second highest frequencies in Europe overlapped with the territories of the largest countries. The genetic structure presented in the composite maps fits major historical geopolitical regions and is in agreement with previous studies of genetic frequencies, validating our approach. Our genetic geostatistical approach provides, on the basis of two composite maps, detailed evidence of the geographical distribution and relative frequencies of the most predominant groups of the extant male European population, examined on the basis of forensic Y-STR haplotypes. The existence of considerable genetic differences among geographic

  3. Genome sequence, comparative analysis and haplotype structure of the domestic dog.

    PubMed

    Lindblad-Toh, Kerstin; Wade, Claire M; Mikkelsen, Tarjei S; Karlsson, Elinor K; Jaffe, David B; Kamal, Michael; Clamp, Michele; Chang, Jean L; Kulbokas, Edward J; Zody, Michael C; Mauceli, Evan; Xie, Xiaohui; Breen, Matthew; Wayne, Robert K; Ostrander, Elaine A; Ponting, Chris P; Galibert, Francis; Smith, Douglas R; DeJong, Pieter J; Kirkness, Ewen; Alvarez, Pablo; Biagi, Tara; Brockman, William; Butler, Jonathan; Chin, Chee-Wye; Cook, April; Cuff, James; Daly, Mark J; DeCaprio, David; Gnerre, Sante; Grabherr, Manfred; Kellis, Manolis; Kleber, Michael; Bardeleben, Carolyne; Goodstadt, Leo; Heger, Andreas; Hitte, Christophe; Kim, Lisa; Koepfli, Klaus-Peter; Parker, Heidi G; Pollinger, John P; Searle, Stephen M J; Sutter, Nathan B; Thomas, Rachael; Webber, Caleb; Baldwin, Jennifer; Abebe, Adal; Abouelleil, Amr; Aftuck, Lynne; Ait-Zahra, Mostafa; Aldredge, Tyler; Allen, Nicole; An, Peter; Anderson, Scott; Antoine, Claudel; Arachchi, Harindra; Aslam, Ali; Ayotte, Laura; Bachantsang, Pasang; Barry, Andrew; Bayul, Tashi; Benamara, Mostafa; Berlin, Aaron; Bessette, Daniel; Blitshteyn, Berta; Bloom, Toby; Blye, Jason; Boguslavskiy, Leonid; Bonnet, Claude; Boukhgalter, Boris; Brown, Adam; Cahill, Patrick; Calixte, Nadia; Camarata, Jody; Cheshatsang, Yama; Chu, Jeffrey; Citroen, Mieke; Collymore, Alville; Cooke, Patrick; Dawoe, Tenzin; Daza, Riza; Decktor, Karin; DeGray, Stuart; Dhargay, Norbu; Dooley, Kimberly; Dooley, Kathleen; Dorje, Passang; Dorjee, Kunsang; Dorris, Lester; Duffey, Noah; Dupes, Alan; Egbiremolen, Osebhajajeme; Elong, Richard; Falk, Jill; Farina, Abderrahim; Faro, Susan; Ferguson, Diallo; Ferreira, Patricia; Fisher, Sheila; FitzGerald, Mike; Foley, Karen; Foley, Chelsea; Franke, Alicia; Friedrich, Dennis; Gage, Diane; Garber, Manuel; Gearin, Gary; Giannoukos, Georgia; Goode, Tina; Goyette, Audra; Graham, Joseph; Grandbois, Edward; Gyaltsen, Kunsang; Hafez, Nabil; Hagopian, Daniel; Hagos, Birhane; Hall, Jennifer; Healy, Claire; Hegarty, Ryan; Honan, Tracey; Horn, Andrea; Houde, Nathan; Hughes, Leanne; Hunnicutt, Leigh; Husby, M; Jester, Benjamin; Jones, Charlien; Kamat, Asha; Kanga, Ben; Kells, Cristyn; Khazanovich, Dmitry; Kieu, Alix Chinh; Kisner, Peter; Kumar, Mayank; Lance, Krista; Landers, Thomas; Lara, Marcia; Lee, William; Leger, Jean-Pierre; Lennon, Niall; Leuper, Lisa; LeVine, Sarah; Liu, Jinlei; Liu, Xiaohong; Lokyitsang, Yeshi; Lokyitsang, Tashi; Lui, Annie; Macdonald, Jan; Major, John; Marabella, Richard; Maru, Kebede; Matthews, Charles; McDonough, Susan; Mehta, Teena; Meldrim, James; Melnikov, Alexandre; Meneus, Louis; Mihalev, Atanas; Mihova, Tanya; Miller, Karen; Mittelman, Rachel; Mlenga, Valentine; Mulrain, Leonidas; Munson, Glen; Navidi, Adam; Naylor, Jerome; Nguyen, Tuyen; Nguyen, Nga; Nguyen, Cindy; Nguyen, Thu; Nicol, Robert; Norbu, Nyima; Norbu, Choe; Novod, Nathaniel; Nyima, Tenchoe; Olandt, Peter; O'Neill, Barry; O'Neill, Keith; Osman, Sahal; Oyono, Lucien; Patti, Christopher; Perrin, Danielle; Phunkhang, Pema; Pierre, Fritz; Priest, Margaret; Rachupka, Anthony; Raghuraman, Sujaa; Rameau, Rayale; Ray, Verneda; Raymond, Christina; Rege, Filip; Rise, Cecil; Rogers, Julie; Rogov, Peter; Sahalie, Julie; Settipalli, Sampath; Sharpe, Theodore; Shea, Terrance; Sheehan, Mechele; Sherpa, Ngawang; Shi, Jianying; Shih, Diana; Sloan, Jessie; Smith, Cherylyn; Sparrow, Todd; Stalker, John; Stange-Thomann, Nicole; Stavropoulos, Sharon; Stone, Catherine; Stone, Sabrina; Sykes, Sean; Tchuinga, Pierre; Tenzing, Pema; Tesfaye, Senait; Thoulutsang, Dawa; Thoulutsang, Yama; Topham, Kerri; Topping, Ira; Tsamla, Tsamla; Vassiliev, Helen; Venkataraman, Vijay; Vo, Andy; Wangchuk, Tsering; Wangdi, Tsering; Weiand, Michael; Wilkinson, Jane; Wilson, Adam; Yadav, Shailendra; Yang, Shuli; Yang, Xiaoping; Young, Geneva; Yu, Qing; Zainoun, Joanne; Zembek, Lisa; Zimmer, Andrew; Lander, Eric S

    2005-12-01

    Here we report a high-quality draft genome sequence of the domestic dog (Canis familiaris), together with a dense map of single nucleotide polymorphisms (SNPs) across breeds. The dog is of particular interest because it provides important evolutionary information and because existing breeds show great phenotypic diversity for morphological, physiological and behavioural traits. We use sequence comparison with the primate and rodent lineages to shed light on the structure and evolution of genomes and genes. Notably, the majority of the most highly conserved non-coding sequences in mammalian genomes are clustered near a small subset of genes with important roles in development. Analysis of SNPs reveals long-range haplotypes across the entire dog genome, and defines the nature of genetic diversity within and across breeds. The current SNP map now makes it possible for genome-wide association studies to identify genes responsible for diseases and traits, with important consequences for human and companion animal health. PMID:16341006

  4. On the relationship between an Asian haplotype on chromosome 6 that reduces androstenone levels in boars and the differential expression of SULT2A1 in the testis

    PubMed Central

    2014-01-01

    variation within SULT2A1, showing that the difference in androstenone levels between the haplotypes is not caused by the SNP in exon 2. PMID:24405739

  5. Identification of Laying-Related SNP Markers in Geese Using RAD Sequencing

    PubMed Central

    Yu, ShiGang; Chu, WeiWei; Zhang, LiFan; Han, HouMing; Zhao, RongXue; Wu, Wei; Zhu, JiangNing; Dodson, Michael V.; Wei, Wei; Liu, HongLin; Chen, Jie

    2015-01-01

    Laying performance is an important economical trait of goose production. As laying performance is of low heritability, it is of significance to develop a marker-assisted selection (MAS) strategy for this trait. Definition of sequence variation related to the target trait is a prerequisite of quantitating MAS, but little is presently known about the goose genome, which greatly hinders the identification of genetic markers for the laying traits of geese. Recently developed restriction site-associated DNA (RAD) sequencing is a possible approach for discerning large-scale single nucleotide polymorphism (SNP) and reducing the complexity of a genome without having reference genomic information available. In the present study, we developed a pooled RAD sequencing strategy for detecting geese laying-related SNP. Two DNA pools were constructed, each consisting of equal amounts of genomic DNA from 10 individuals with either high estimated breeding value (HEBV) or low estimated breeding value (LEBV). A total of 139,013 SNP were obtained from 42,291,356 sequences, of which 18,771,943 were for LEBV and 23,519,413 were for HEBV cohorts. Fifty-five SNP which had different allelic frequencies in the two DNA pools were further validated by individual-based AS-PCR genotyping in the LEBV and HEBV cohorts. Ten out of 55 SNP exhibited distinct allele distributions in these two cohorts. These 10 SNP were further genotyped in a goose population of 492 geese to verify the association with egg numbers. The result showed that 8 of 10 SNP were associated with egg numbers. Additionally, liner regression analysis revealed that SNP Record-111407, 106975 and 112359 were involved in a multiplegene network affecting laying performance. We used IPCR to extend the unknown regions flanking the candidate RAD tags. The obtained sequences were subjected to BLAST to retrieve the orthologous genes in either ducks or chickens. Five novel genes were cloned for geese which harbored the candidate laying

  6. Identification of Laying-Related SNP Markers in Geese Using RAD Sequencing.

    PubMed

    Yu, ShiGang; Chu, WeiWei; Zhang, LiFan; Han, HouMing; Zhao, RongXue; Wu, Wei; Zhu, JiangNing; Dodson, Michael V; Wei, Wei; Liu, HongLin; Chen, Jie

    2015-01-01

    Laying performance is an important economical trait of goose production. As laying performance is of low heritability, it is of significance to develop a marker-assisted selection (MAS) strategy for this trait. Definition of sequence variation related to the target trait is a prerequisite of quantitating MAS, but little is presently known about the goose genome, which greatly hinders the identification of genetic markers for the laying traits of geese. Recently developed restriction site-associated DNA (RAD) sequencing is a possible approach for discerning large-scale single nucleotide polymorphism (SNP) and reducing the complexity of a genome without having reference genomic information available. In the present study, we developed a pooled RAD sequencing strategy for detecting geese laying-related SNP. Two DNA pools were constructed, each consisting of equal amounts of genomic DNA from 10 individuals with either high estimated breeding value (HEBV) or low estimated breeding value (LEBV). A total of 139,013 SNP were obtained from 42,291,356 sequences, of which 18,771,943 were for LEBV and 23,519,413 were for HEBV cohorts. Fifty-five SNP which had different allelic frequencies in the two DNA pools were further validated by individual-based AS-PCR genotyping in the LEBV and HEBV cohorts. Ten out of 55 SNP exhibited distinct allele distributions in these two cohorts. These 10 SNP were further genotyped in a goose population of 492 geese to verify the association with egg numbers. The result showed that 8 of 10 SNP were associated with egg numbers. Additionally, liner regression analysis revealed that SNP Record-111407, 106975 and 112359 were involved in a multiplegene network affecting laying performance. We used IPCR to extend the unknown regions flanking the candidate RAD tags. The obtained sequences were subjected to BLAST to retrieve the orthologous genes in either ducks or chickens. Five novel genes were cloned for geese which harbored the candidate laying

  7. New DNA polymorphisms define ethnically distinct haplotypes in the human transferrin receptor gene.

    PubMed

    Van Landeghem, G F; Beckman, L E; Sikström, C; Saha, N; Kucinskas, V; Beckman, L

    1998-01-01

    In a study of transferrin receptor (TFR) polymorphism in different ethnic groups using PCR and restriction cleavage we found a new Hin6I polymorphism in intron 7 and confirmed a tentative BanI polymorphism in exon 4 reported by Evans and Kemp [Gene 1997;199:123-131]. In all ethnic groups there was a complete and highly significant (p < 10(-10)) linkage disequilibrium where all BanI 1 alleles were linked to Hin6I 1 alleles. Furthermore in the European populations, but not in the Chinese, there was a close correlation between the three BanI-Hin6I haplotypes and the alleles of a previously described three-allelic RsaI polymorphism in the TFR gene studied by Southern blotting. There were distinct ethnic differences in TFR allele and haplotype frequencies. Thus the Saamis were significantly different from the other European ethnic groups, and the Lithuanians had a significantly increased frequency of the BanI 2-Hin6I 1 haplotype, suggesting that this marker may be informative in tracing prehistoric migrations and admixture by Baltic peoples. The new TFR polymorphisms and haplotypes may also be useful markers in studies of interactions with the transferrin and hemochromatosis genes, the genetic influence on body iron stores and disease associations. PMID:9748693

  8. A hidden Markov model for investigating recent positive selection through haplotype structure.

    PubMed

    Chen, Hua; Hey, Jody; Slatkin, Montgomery

    2015-02-01

    Recent positive selection can increase the frequency of an advantageous mutant rapidly enough that a relatively long ancestral haplotype will be remained intact around it. We present a hidden Markov model (HMM) to identify such haplotype structures. With HMM identified haplotype structures, a population genetic model for the extent of ancestral haplotypes is then adopted for parameter inference of the selection intensity and the allele age. Simulations show that this method can detect selection under a wide range of conditions and has higher power than the existing frequency spectrum-based method. In addition, it provides good estimate of the selection coefficients and allele ages for strong selection. The method analyzes large data sets in a reasonable amount of running time. This method is applied to HapMap III data for a genome scan, and identifies a list of candidate regions putatively under recent positive selection. It is also applied to several genes known to be under recent positive selection, including the LCT, KITLG and TYRP1 genes in Northern Europeans, and OCA2 in East Asians, to estimate their allele ages and selection coefficients. PMID:25446961

  9. A Hidden Markov Model for Investigating Recent Positive Selection through Haplotype Structure

    PubMed Central

    Hey, Jody; Slatkin, Montgomery

    2014-01-01

    Recent positive selection can increase the frequency of an advantageous mutant rapidly enough that a relatively long ancestral haplotype will be remained intact around it. We present a hidden Markov model (HMM) to identify such haplotype structures. With HMM identified haplotype structures, a population genetic model for the extent of ancestral haplotypes is then adopted for parameter inference of the selection intensity and the allele age. Simulations show that this method can detect selection under a wide range of conditions and has higher power than the existing frequency spectrum-based method. In addition, it provides good estimate of the selection coefficients and allele ages for strong selection. The method analyzes large data sets in a reasonable amount of running time. This method is applied to HapMap III data for a genome scan, and identifies a list of candidate regions putatively under recent positive selection. It is also applied to several genes known to be under recent positive selection, including the LCT, KITLG and TYRP1 genes in Northern Europeans, and OCA2 in East Asians, to estimate their allele ages and selection coefficients. PMID:25446961

  10. Haplotype structure in Ashkenazi Jewish BRCA1 and BRCA2 mutation carriers.

    PubMed

    Im, Kate M; Kirchhoff, Tomas; Wang, Xianshu; Green, Todd; Chow, Clement Y; Vijai, Joseph; Korn, Joshua; Gaudet, Mia M; Fredericksen, Zachary; Shane Pankratz, V; Guiducci, Candace; Crenshaw, Andrew; McGuffog, Lesley; Kartsonaki, Christiana; Morrison, Jonathan; Healey, Sue; Sinilnikova, Olga M; Mai, Phuong L; Greene, Mark H; Piedmonte, Marion; Rubinstein, Wendy S; Hogervorst, Frans B; Rookus, Matti A; Collée, J Margriet; Hoogerbrugge, Nicoline; van Asperen, Christi J; Meijers-Heijboer, Hanne E J; Van Roozendaal, Cees E; Caldes, Trinidad; Perez-Segura, Pedro; Jakubowska, Anna; Lubinski, Jan; Huzarski, Tomasz; Blecharz, Paweł; Nevanlinna, Heli; Aittomäki, Kristiina; Lazaro, Conxi; Blanco, Ignacio; Barkardottir, Rosa B; Montagna, Marco; D'Andrea, Emma; Devilee, Peter; Olopade, Olufunmilayo I; Neuhausen, Susan L; Peissel, Bernard; Bonanni, Bernardo; Peterlongo, Paolo; Singer, Christian F; Rennert, Gad; Lejbkowicz, Flavio; Andrulis, Irene L; Glendon, Gord; Ozcelik, Hilmi; Toland, Amanda Ewart; Caligo, Maria Adelaide; Beattie, Mary S; Chan, Salina; Domchek, Susan M; Nathanson, Katherine L; Rebbeck, Timothy R; Phelan, Catherine; Narod, Steven; John, Esther M; Hopper, John L; Buys, Saundra S; Daly, Mary B; Southey, Melissa C; Terry, Mary-Beth; Tung, Nadine; Hansen, Thomas V O; Osorio, Ana; Benitez, Javier; Durán, Mercedes; Weitzel, Jeffrey N; Garber, Judy; Hamann, Ute; Peock, Susan; Cook, Margaret; Oliver, Clare T; Frost, Debra; Platte, Radka; Evans, D Gareth; Eeles, Ros; Izatt, Louise; Paterson, Joan; Brewer, Carole; Hodgson, Shirley; Morrison, Patrick J; Porteous, Mary; Walker, Lisa; Rogers, Mark T; Side, Lucy E; Godwin, Andrew K; Schmutzler, Rita K; Wappenschmidt, Barbara; Laitman, Yael; Meindl, Alfons; Deissler, Helmut; Varon-Mateeva, Raymonda; Preisler-Adams, Sabine; Kast, Karin; Venat-Bouvet, Laurence; Stoppa-Lyonnet, Dominique; Chenevix-Trench, Georgia; Easton, Douglas F; Klein, Robert J; Daly, Mark J; Friedman, Eitan; Dean, Michael; Clark, Andrew G; Altshuler, David M; Antoniou, Antonis C; Couch, Fergus J; Offit, Kenneth; Gold, Bert

    2011-11-01

    Three founder mutations in BRCA1 and BRCA2 contribute to the risk of hereditary breast and ovarian cancer in Ashkenazi Jews (AJ). They are observed at increased frequency in the AJ compared to other BRCA mutations in Caucasian non-Jews (CNJ). Several authors have proposed that elevated allele frequencies in the surrounding genomic regions reflect adaptive or balancing selection. Such proposals predict long-range linkage disequilibrium (LD) resulting from a selective sweep, although genetic drift in a founder population may also act to create long-distance LD. To date, few studies have used the tools of statistical genomics to examine the likelihood of long-range LD at a deleterious locus in a population that faced a genetic bottleneck. We studied the genotypes of hundreds of women from a large international consortium of BRCA1 and BRCA2 mutation carriers and found that AJ women exhibited long-range haplotypes compared to CNJ women. More than 50% of the AJ chromosomes with the BRCA1 185delAG mutation share an identical 2.1 Mb haplotype and nearly 16% of AJ chromosomes carrying the BRCA2 6174delT mutation share a 1.4 Mb haplotype. Simulations based on the best inference of Ashkenazi population demography indicate that long-range haplotypes are expected in the context of a genome-wide survey. Our results are consistent with the hypothesis that a local bottleneck effect from population size constriction events could by chance have resulted in the large haplotype blocks observed at high frequency in the BRCA1 and BRCA2 regions of Ashkenazi Jews. PMID:21597964

  11. Haplotype structure in Ashkenazi Jewish BRCA1 and BRCA2 mutation carriers

    PubMed Central

    Im, Kate M.; Kirchhoff, Tomas; Wang, Xianshu; Green, Todd; Chow, Clement Y.; Vijai, Joseph; Korn, Joshua; Gaudet, Mia M.; Fredericksen, Zachary; Pankratz, V. Shane; Guiducci, Candace; Crenshaw, Andrew; McGuffog, Lesley; Kartsonaki, Christiana; Morrison, Jonathan; Healey, Sue; Sinilnikova, Olga M.; Mai, Phuong L.; Greene, Mark H.; Piedmonte, Marion; Rubinstein, Wendy S.; Hogervorst, Frans B.; Rookus, Matti A.; Collée, J. Margriet; Hoogerbrugge, Nicoline; van Asperen, Christi J.; Meijers-Heijboer, Hanne E. J.; Van Roozendaal, Cees E.; Caldes, Trinidad; Perez-Segura, Pedro; Jakubowska, Anna; Lubinski, Jan; Huzarski, Tomasz; Blecharz, Paweł; Nevanlinna, Heli; Aittomäki, Kristiina; Lazaro, Conxi; Blanco, Ignacio; Barkardottir, Rosa B.; Montagna, Marco; D'Andrea, Emma; Devilee, Peter; Olopade, Olufunmilayo I.; Neuhausen, Susan L.; Peissel, Bernard; Bonanni, Bernardo; Peterlongo, Paolo; Singer, Christian F.; Rennert, Gad; Lejbkowicz, Flavio; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Toland, Amanda Ewart; Caligo, Maria Adelaide; Beattie, Mary S.; Chan, Salina; Domchek, Susan M.; Nathanson, Katherine L.; Rebbeck, Timothy R.; Phelan, Catherine; Narod, Steven; John, Esther M.; Hopper, John L.; Buys, Saundra S.; Daly, Mary B.; Southey, Melissa C.; Terry, Mary-Beth; Tung, Nadine; Hansen, Thomas v. O.; Osorio, Ana; Benitez, Javier; Durán, Mercedes; Weitzel, Jeffrey N.; Garber, Judy; Hamann, Ute; Peock, Susan; Cook, Margaret; Oliver, Clare T.; Frost, Debra; Platte, Radka; Evans, D. Gareth; Eeles, Ros; Izatt, Louise; Paterson, Joan; Brewer, Carole; Hodgson, Shirley; Morrison, Patrick J.; Porteous, Mary; Walker, Lisa; Rogers, Mark T.; Side, Lucy E.; Godwin, Andrew K.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Laitman, Yael; Meindl, Alfons; Deissler, Helmut; Varon-Mateeva, Raymonda; Preisler-Adams, Sabine; Kast, Karin; Venat-Bouvet, Laurence; Stoppa-Lyonnet, Dominique; Chenevix-Trench, Georgia; Easton, Douglas F.; Klein, Robert J.; Daly, Mark J.; Friedman, Eitan; Dean, Michael; Clark, Andrew G.; Altshuler, David M.; Antoniou, Antonis C.; Couch, Fergus J.; Offit, Kenneth; Gold, Bert

    2011-01-01

    Abstract Three founder mutations in BRCA1 and BRCA2 contribute to the risk of hereditary breast and ovarian cancer in Ashkenazi Jews (AJ). They are observed at increased frequency in the AJ compared to other BRCA mutations in Caucasian non-Jews (CNJ). Several authors have proposed that elevated allele frequencies in the surrounding genomic regions reflect adaptive or balancing selection. Such proposals predict long-range linkage dis-equilibrium (LD) resulting from a selective sweep, although genetic drift in a founder population may also act to create long-distance LD. To date, few studies have used the tools of statistical genomics to examine the likelihood of long-range LD at a deleterious locus in a population that faced a genetic bottleneck. We studied the genotypes of hundreds of women from a large international consortium of BRCA1 and BRCA2 mutation carriers and found that AJ women exhibited long-range haplotypes compared to CNJ women. More than 50% of the AJ chromosomes with the BRCA1 185delAG mutation share an identical 2.1 Mb haplotype and nearly 16% of AJ chromosomes carrying the BRCA2 6174delT mutation share a 1.4 Mb haplotype. Simulations based on the best inference of Ashkenazi population demography indicate that long-range haplotypes are expected in the context of a genome-wide survey. Our results are consistent with the hypothesis that a local bottleneck effect from population size constriction events could by chance have resulted in the large haplotype blocks observed at high frequency in the BRCA1 and BRCA2 regions of Ashkenazi Jews. PMID:21597964

  12. MHC class II alleles and haplotypes in patients with pemphigus vulgaris from India.

    PubMed

    Delgado, J C; Yunis, D E; Bozón, M V; Salazar, M; Deulofeut, R; Turbay, D; Mehra, N K; Pasricha, J S; Raval, R S; Patel, H; Shah, B K; Bhol, K; Alper, C A; Ahmed, A R; Yunis, E J

    1996-12-01

    Pemphigus vulgaris (PV) is a blistering disease of the skin and mucous membranes characterized by an autoantibody response against a keratinocyte adhesion molecule, desmoglein 3, causing acantholysis and blister formation. We compared high resolution MHC class II alleles and haplotype frequencies (HLA-DRB, DQA1 and DQB1) in 37 patients with PV to 89 haplotypes of normal relatives from New Delhi and Ahmedabad. We found that PV patients had significantly increased frequencies of DRB1*1404 (P < 0.0001), DQA1*0101 (P = 0.001), and DQB1*0503 (P < 0.0001). These associations were due to the increased frequencies of the haplotype HLA-DRB1*1404, DRB3*0202, DQA1*0101, DQB1*0503 in patients compared to control haplotypes (p < 0.0001). Also, patients from Ahmedabad had a significant increase in HLA-DQB1*0302 (p = 0.03). An identical amino acid sequence (Leu-Leu-Glu-Arg-Arg-Arg-Ala-Glu), in positions 67-74 of the beta domain of DRB alleles is restricted to some DR14 alleles. Therefore, there are three possible explanations for class II allele involvement in autoantibody in PV patients with class II haplotypes marked by HLA-DR14. First, the class II alleles could be markers for an unidentified susceptibility gene in linkage disequilibrium with them. Second, the primary association could be with DQB1*0503 and the association with HLA-DR14 alleles would be the result of linkage disequilibrium. Third, the HLA-DRB1 locus susceptibility could involve a specific amino acid sequence in the third hypervariable region shared by several HLA-DR14 alleles. PMID:9008309

  13. Genome-wide haplotype association study identifies the FRMD4A gene as a risk locus for Alzheimer's disease

    PubMed Central

    Lambert, J-C; Grenier-Boley, B; Harold, D; Zelenika, D; Chouraki, V; Kamatani, Y; Sleegers, K; Ikram, M A; Hiltunen, M; Reitz, C; Mateo, I; Feulner, T; Bullido, M; Galimberti, D; Concari, L; Alvarez, V; Sims, R; Gerrish, A; Chapman, J; Deniz-Naranjo, C; Solfrizzi, V; Sorbi, S; Arosio, B; Spalletta, G; Siciliano, G; Epelbaum, J; Hannequin, D; Dartigues, J-F; Tzourio, C; Berr, C; Schrijvers, E M C; Rogers, R; Tosto, G; Pasquier, F; Bettens, K; Van Cauwenberghe, C; Fratiglioni, L; Graff, C; Delepine, M; Ferri, R; Reynolds, C A; Lannfelt, L; Ingelsson, M; Prince, J A; Chillotti, C; Pilotto, A; Seripa, D; Boland, A; Mancuso, M; Bossù, P; Annoni, G; Nacmias, B; Bosco, P; Panza, F; Sanchez-Garcia, F; Del Zompo, M; Coto, E; Owen, M; O'Donovan, M; Valdivieso, F; Caffara, P; Scarpini, E; Combarros, O; Buée, L; Campion, D; Soininen, H; Breteler, M; Riemenschneider, M; Van Broeckhoven, C; Alpérovitch, A; Lathrop, M; Trégouët, D-A; Williams, J; Amouyel, P

    2013-01-01

    Recently, several genome-wide association studies (GWASs) have led to the discovery of nine new loci of genetic susceptibility in Alzheimer's disease (AD). However, the landscape of the AD genetic susceptibility is far away to be complete and in addition to single-SNP (single-nucleotide polymorphism) analyses as performed in conventional GWAS, complementary strategies need to be applied to overcome limitations inherent to this type of approaches. We performed a genome-wide haplotype association (GWHA) study in the EADI1 study (n=2025 AD cases and 5328 controls) by applying a sliding-windows approach. After exclusion of loci already known to be involved in AD (APOE, BIN1 and CR1), 91 regions with suggestive haplotype effects were identified. In a second step, we attempted to replicate the best suggestive haplotype associations in the GERAD1 consortium (2820 AD cases and 6356 controls) and observed that 9 of them showed nominal association. In a third step, we tested relevant haplotype associations in a combined analysis of five additional case–control studies (5093 AD cases and 4061 controls). We consistently replicated the association of a haplotype within FRMD4A on Chr.10p13 in all the data set analyzed (OR: 1.68; 95% CI: (1.43–1.96); P=1.1 × 10−10). We finally searched for association between SNPs within the FRMD4A locus and Aβ plasma concentrations in three independent non-demented populations (n=2579). We reported that polymorphisms were associated with plasma Aβ42/Aβ40 ratio (best signal, P=5.4 × 10−7). In conclusion, combining both GWHA study and a conservative three-stage replication approach, we characterised FRMD4A as a new genetic risk factor of AD. PMID:22430674

  14. A functional haplotype implicated in vulnerability to develop cocaine dependence is associated with reduced PDYN expression in human brain.

    PubMed

    Yuferov, Vadim; Ji, Fei; Nielsen, David A; Levran, Orna; Ho, Ann; Morgello, Susan; Shi, Ruijin; Ott, Jurg; Kreek, Mary Jeanne

    2009-04-01

    Dynorphin peptides and the kappa-opioid receptor are important in the rewarding properties of cocaine, heroin, and alcohol. We tested polymorphisms of the prodynorphin gene (PDYN) for association with cocaine dependence and cocaine/alcohol codependence. We genotyped six single nucleotide polymorphisms (SNPs), located in the promoter region, exon 4 coding, and 3' untranslated region, in 106 Caucasians and 204 African Americans who were cocaine dependent, cocaine/alcohol codependent, or controls. In Caucasians, we found point-wise significant associations of 3'UTR SNPs (rs910080, rs910079, and rs2235749) with cocaine dependence and cocaine/alcohol codependence. These SNPs are in high linkage disequilibrium, comprising a haplotype block. The haplotype CCT was significantly experiment-wise associated with cocaine dependence and with combined cocaine dependence and cocaine/alcohol codependence (false discovery rate, q=0.04 and 0.03, respectively). We investigated allele-specific gene expression of PDYN, using SNP rs910079 as a reporter, in postmortem human brains from eight heterozygous subjects, using SNaPshot assay. There was significantly lower expression for C allele (rs910079), with ratios ranging from 0.48 to 0.78, indicating lower expression of the CCT haplotype of PDYN in both the caudate and nucleus accumbens. Analysis of total PDYN expression in 43 postmortem brains also showed significantly lower levels of preprodynorphin mRNA in subjects having the risk CCT haplotype. This study provides evidence that a 3'UTR PDYN haplotype, implicated in vulnerability to develop cocaine addiction and/or cocaine/alcohol codependence, is related to lower mRNA expression of the PDYN gene in human dorsal and ventral striatum. PMID:18923396

  15. Unique haplotypes of cacao trees as revealed by trnH-psbA chloroplast DNA.

    PubMed

    Gutiérrez-López, Nidia; Ovando-Medina, Isidro; Salvador-Figueroa, Miguel; Molina-Freaner, Francisco; Avendaño-Arrazate, Carlos H; Vázquez-Ovando, Alfredo

    2016-01-01

    Cacao trees have been cultivated in Mesoamerica for at least 4,000 years. In this study, we analyzed sequence variation in the chloroplast DNA trnH-psbA intergenic spacer from 28 cacao trees from different farms in the Soconusco region in southern Mexico. Genetic relationships were established by two analysis approaches based on geographic origin (five populations) and genetic origin (based on a previous study). We identified six polymorphic sites, including five insertion/deletion (indels) types and one transversion. The overall nucleotide diversity was low for both approaches (geographic = 0.0032 and genetic = 0.0038). Conversely, we obtained moderate to high haplotype diversity (0.66 and 0.80) with 10 and 12 haplotypes, respectively. The common haplotype (H1) for both networks included cacao trees from all geographic locations (geographic approach) and four genetic groups (genetic approach). This common haplotype (ancient) derived a set of intermediate haplotypes and singletons interconnected by one or two mutational steps, which suggested directional selection and event purification from the expansion of narrow populations. Cacao trees from Soconusco region were grouped into one cluster without any evidence of subclustering based on AMOVA (F ST = 0) and SAMOVA (F ST = 0.04393) results. One population (Mazatán) showed a high haplotype frequency; thus, this population could be considered an important reservoir of genetic material. The indels located in the trnH-psbA intergenic spacer of cacao trees could be useful as markers for the development of DNA barcoding. PMID:27076998

  16. Haplotype diversity generated by ancient recombination-like events in the MHC of Indian rhesus macaques.

    PubMed

    Doxiadis, Gaby G M; de Groot, Nanine; Otting, Nel; de Vos-Rouweler, Annemiek J M; Bolijn, Maria J; Heijmans, Corrine M C; de Groot, Natasja G; van der Wiel, Marit K H; Remarque, Edmond J; Vangenot, Christelle; Nunes, José M; Sanchez-Mazas, Alicia; Bontrop, Ronald E

    2013-08-01

    The Mamu-A, Mamu-B, and Mamu-DRB genes of the rhesus macaque show several levels of complexity such as allelic heterogeneity (polymorphism), copy number variation, differential segregation of genes/alleles present on a haplotype (diversity) and transcription level differences. A combination of techniques was implemented to screen a large panel of pedigreed Indian rhesus macaques (1,384 individuals representing the offspring of 137 founding animals) for haplotype diversity in an efficient and inexpensive manner. This approach allowed the definition of 140 haplotypes that display a relatively low degree of region variation as reflected by the presence of only 17 A, 18 B and 22 DRB types, respectively, exhibiting a global linkage disequilibrium comparable to that in humans. This finding contrasts with the situation observed in rhesus macaques from other geographic origins and in cynomolgus monkeys from Indonesia. In these latter populations, nearly every haplotype appears to be characterised by a unique A, B and DRB region. In the Indian population, however, a reshuffling of existing segments generated "new" haplotypes. Since the recombination frequency within the core MHC of the Indian rhesus macaques is relatively low, the various haplotypes were most probably produced by recombination events that accumulated over a long evolutionary time span. This idea is in accord with the notion that Indian rhesus macaques experienced a severe reduction in population during the Pleistocene due to a bottleneck caused by geographic changes. Thus, recombination-like processes appear to be a way to expand a diminished genetic repertoire in an isolated and relatively small founder population. PMID:23715823

  17. Global selection on sucrose synthase haplotypes during a century of wheat breeding.

    PubMed

    Hou, Jian; Jiang, Qiyan; Hao, Chenyang; Wang, Yuquan; Zhang, Hongna; Zhang, Xueyong

    2014-04-01

    Spike number per unit area, number of grains per spike, and thousand kernel weight (TKW) are important yield components. In China, increases in wheat (Triticum aestivum) yields are mainly due to increases in grain number per spike and TKW. TKW mainly depends on starch content, as starch accounts for about 70% of the grain endosperm. Sucrose synthase catalysis is the first step in the conversion of sucrose to starch, that is, the conversion of sucrose to fructose and UDP-glucose by the wheat sucrose synthase genes (TaSus1 and TaSus2) that are located on chromosomes 7A/7B/7D and 2A/2B/2D, respectively. A total of 1,520 wheat accessions were genotyped at the six loci. Two, two, five, and two haplotypes were identified at the TaSus2-2A, TaSus2-2B, TaSus1-7A, and TaSus1-7B loci, respectively. Their main variations were detected within the introns. Significant differences between the haplotypes correlated with TKW differences among 348 modern Chinese cultivars from the core collection. Frequency changes for favored haplotypes showed gradual increases in cultivars released since beginning of the last century in China, Europe, and North America. Geographic distributions and time changes of favored haplotypes were characterized in six major wheat production regions worldwide. Strong selection bottlenecks to haplotype variations occurred at polyploidization and domestication and during breeding of wheat. Genetic-effect differences between haplotypes at the same locus influence the selection time and intensity. This work shows that the endosperm starch synthesis pathway is a major target of indirect selection in global wheat breeding for higher yield. PMID:24402050

  18. Beta-Globin Gene Haplotypes Among Cameroonians and Review of the Global Distribution: Is There a Case for a Single Sickle Mutation Origin in Africa?

    PubMed Central

    Bitoungui, Valentina J. Ngo; Pule, Gift D.; Hanchard, Neil; Ngogang, Jeanne

    2015-01-01

    Abstract Studies of hemoglobin S haplotypes in African subpopulations have potential implications for patient care and our understanding of genetic factors that have shaped the prevalence of sickle cell disease (SCD). We evaluated HBB gene cluster haplotypes in SCD patients from Cameroon, and reviewed the literature for a global distribution. We reviewed medical records to obtain pertinent socio-demographic and clinical features for 610 Cameroonian SCD patients, including hemoglobin electrophoresis and full blood counts. RFLP-PCR was used to determine the HBB gene haplotype on 1082 chromosomes. A systematic review of the current literature was undertaken to catalogue HBB haplotype frequencies in SCD populations around the world. Benin (74%; n=799) and Cameroon (19%; n=207) were the most prevalent haplotypes observed among Cameroonian patients. There was no significant association between HBB haplotypes and clinical life events, anthropometric measures, hematological parameters, or fetal hemoglobin (HbF) levels. The literature review of the global haplotype distributions was consistent with known historical migrations of the people of Africa. Previously reported data from Sudan showed a distinctly unusual pattern; all four classical haplotypes were reported, with an exceptionally high proportion of the Senegal, Cameroon, and atypical haplotypes. We did not observe any significant associations between HBB haplotype and SCD disease course in this cohort. Taken together, the data from Cameroon and from the wider literature suggest that a careful reassessment of African HBB haplotypes may shed further light on the evolutionary dynamics of the sickle allele, which could suggest a single origin of the sickle mutation. PMID:25748438

  19. Beta-globin gene haplotypes among cameroonians and review of the global distribution: is there a case for a single sickle mutation origin in Africa?

    PubMed

    Bitoungui, Valentina J Ngo; Pule, Gift D; Hanchard, Neil; Ngogang, Jeanne; Wonkam, Ambroise

    2015-03-01

    Studies of hemoglobin S haplotypes in African subpopulations have potential implications for patient care and our understanding of genetic factors that have shaped the prevalence of sickle cell disease (SCD). We evaluated HBB gene cluster haplotypes in SCD patients from Cameroon, and reviewed the literature for a global distribution. We reviewed medical records to obtain pertinent socio-demographic and clinical features for 610 Cameroonian SCD patients, including hemoglobin electrophoresis and full blood counts. RFLP-PCR was used to determine the HBB gene haplotype on 1082 chromosomes. A systematic review of the current literature was undertaken to catalogue HBB haplotype frequencies in SCD populations around the world. Benin (74%; n = 799) and Cameroon (19%; n = 207) were the most prevalent haplotypes observed among Cameroonian patients. There was no significant association between HBB haplotypes and clinical life events, anthropometric measures, hematological parameters, or fetal hemoglobin (HbF) levels. The literature review of the global haplotype distributions was consistent with known historical migrations of the people of Africa. Previously reported data from Sudan showed a distinctly unusual pattern; all four classical haplotypes were reported, with an exceptionally high proportion of the Senegal, Cameroon, and atypical haplotypes. We did not observe any significant associations between HBB haplotype and SCD disease course in this cohort. Taken together, the data from Cameroon and from the wider literature suggest that a careful reassessment of African HBB haplotypes may shed further light on the evolutionary dynamics of the sickle allele, which could suggest a single origin of the sickle mutation. PMID:25748438

  20. A SNP-Based Molecular Barcode for Characterization of Common Wheat

    PubMed Central

    Gao, LiFeng; Jia, JiZeng; Kong, XiuYing

    2016-01-01

    Wheat is grown as a staple crop worldwide. It is important to develop an effective genotyping tool for this cereal grain both to identify germplasm diversity and to protect the rights of breeders. Single-nucleotide polymorphism (SNP) genotyping provides a means for developing a practical, rapid, inexpensive and high-throughput assay. Here, we investigated SNPs as robust markers of genetic variation for typing wheat cultivars. We identified SNPs from an array of 9000 across a collection of 429 well-known wheat cultivars grown in China, of which 43 SNP markers with high minor allele frequency and variations discriminated the selected wheat varieties and their wild ancestors. This SNP-based barcode will allow for the rapid and precise identification of wheat germplasm resources and newly released varieties and will further assist in the wheat breeding program. PMID:26985664

  1. A SNP-Based Molecular Barcode for Characterization of Common Wheat.

    PubMed

    Gao, LiFeng; Jia, JiZeng; Kong, XiuYing

    2016-01-01

    Wheat is grown as a staple crop worldwide. It is important to develop an effective genotyping tool for this cereal grain both to identify germplasm diversity and to protect the rights of breeders. Single-nucleotide polymorphism (SNP) genotyping provides a means for developing a practical, rapid, inexpensive and high-throughput assay. Here, we investigated SNPs as robust markers of genetic variation for typing wheat cultivars. We identified SNPs from an array of 9000 across a collection of 429 well-known wheat cultivars grown in China, of which 43 SNP markers with high minor allele frequency and variations discriminated the selected wheat varieties and their wild ancestors. This SNP-based barcode will allow for the rapid and precise identification of wheat germplasm resources and newly released varieties and will further assist in the wheat breeding program. PMID:26985664

  2. Sickle cell disorder, beta-globin gene cluster haplotypes and alpha-thalassemia in neonates and adults from Guadeloupe.

    PubMed

    Kéclard, L; Romana, M; Lavocat, E; Saint-Martin, C; Berchel, C; Mérault, G

    1997-05-01

    We have studied haplotype of beta(S) chromosome and alpha-globin gene status in 534 patients (255 adults and 279 children of whom 159 neonates) from Guadeloupe with various sickle cell-related conditions, namely SS (n = 298), SC (n = 170), S-beta-thal (n = 56), and other rare forms (n = 10). Haplotype data on beta(S) chromosomes confirm our previous observation that Benin type is the most prevalent (75%) beta(S) chromosome in Guadeloupe, in disagreement with the historical records. Comparison of the frequency of distribution of various beta(S) haplotypes between neonates and adults on the one hand and between SS and SC cases on the other shows that the current beta(S) haplotype distribution in this island is not distorted by haplotype-related differential survival. We also show that the frequency of alpha-thalassemia (-3.7 kb) in Guadeloupe is one of the highest recorded in this region involved in Atlantic slave trade and also failed to reveal any age-dependent increase in frequency. We conclude that the African component of Guadeloupe is distinct from that of Brazil and Cuba but is close to that of Jamaica. PMID:9136913

  3. The Wilson disease gene: Haplotypes and mutations

    SciTech Connect

    Thomas, G.R.; Roberts, E.A.; Cox, D.W.; Walshe, J.M.

    1994-09-01

    Wilson disease (WND) is an autosomal recessive defect of copper transport. The gene involved in WND, located on chromosome 13, has recently been shown to be a putative copper transporting P-type ATPase, designated ATP7B. The gene is highly similar to ATP7A, located on the X chromosome, which is defective in Menkes disease, another disorder of copper transport. We have available for study WND families from Canada (34 families), the United Kingdom (32 families), Japan (4 families), Iceland (3 families) and Hong Kong (2 families). We have utilized four highly polymorphic CA repeat markers (D13S296, D13S301, D13S314 and D13S316) surrounding the ATP7B locus to construct haplotypes in these families. Analysis indicates that there are many unique WND haplotypes not present on normal chromosomes and that there may be a large number of different WND mutations. We have screened the WND patients for mutations in the ATP7B gene. Fifty six patients, representing all of the identified haplotypes, have been screened using single strand conformational polymorphism (SSCP), followed by selective sequencing. To date, 19 mutations and 12 polymorphisms have been identified. All of the changes are nucleotide substitutions or small insertions/deletions and there is no evidence for larger deletions as seen in the similar gene on the X chromosome, ATP7A. Haplotypes of close markers and the ability to detect some of the mutations present in the gene allow for more reliable molecular diagnosis of presymptomatic sibs of WND patients. A reassessment of individuals previously diagnosed in the presymptomatic phase is now required, as we have have identified some heterozygotes who are biochemically indistinguishable from affected homozygotes. The identification of specific mutations will soon allow direct diagnosis of WND patients with a high level of certainty.

  4. Haplotypes of the WNK1 gene associate with blood pressure variation in a severely hypertensive population from the British Genetics of Hypertension study.

    PubMed

    Newhouse, Stephen J; Wallace, Chris; Dobson, Richard; Mein, Charles; Pembroke, Janine; Farrall, Martin; Clayton, David; Brown, Morris; Samani, Nilesh; Dominiczak, Anna; Connell, John M; Webster, John; Lathrop, G Mark; Caulfield, Mark; Munroe, Patricia B

    2005-07-01

    Mutations in the WNK1 gene cause Gordon's syndrome, a rare Mendelian form of hypertension. We assessed whether common WNK1 variants might also contribute to essential hypertension (EH), a multifactorial disorder affecting > 25% of the adult population worldwide. A panel of 19 single nucleotide polymorphisms (SNPs) spanning the gene was selected from public databases and was genotyped in 100 white European families to determine the pattern of linkage disequilibrium, haplotype structure and tagging SNPs for the WNK1 locus. Eight tagging SNPs were identified with 90% power to predict common WNK1 haplotypes and SNPs. Family-based association tests were used to test for association with EH and severity of hypertension in 712 severely hypertensive families from the MRC British Genetics of Hypertension study resource. No association was found between WNK1 polymorphisms or haplotypes with hypertension; however, one SNP rs1468326, located 3 kb from the WNK1 promoter, was found to be nominally associated with severity of hypertension, with both systolic blood pressure (BP) (Z = +2.24, P = 0.025) and diastolic BP (Z = +1.99, P = 0.046). We also found nominal support for association of one common WNK1 haplotype with increased systolic BP (Z = +1.91, P = 0.053). This is the first study to perform haplotype association analysis of the WNK1 gene with EH. This finding of association between a SNP near the promoter region and the severity of hypertension suggests that increased expression of WNK1 might contribute to BP variability and susceptibility to EH similar to the mechanism of hypertension observed in Gordon's syndrome. PMID:15888480

  5. Evidence that the ancestral haplotype in Australian hemochromatosis patients may be associated with a common mutation in the gene

    SciTech Connect

    Crawford, D.H.G.; Powell, L.W.; Leggett, B.A.

    1995-08-01

    Hemochromatosis (HC) is a common inherited disorder of iron metabolism for which neither the gene nor biochemical defect have yet been identified. The aim of this study was to look for clinical evidence that the predominant ancestral haplotype in Australian patients is associated with a common mutation in the gene. We compared indices of iron metabolism and storage in three groups of HC patients categorized according to the presence of the ancestral haplotype (i.e., patients with two copies, one copy, and no copies of the ancestral haplotype). We also examined iron indices in two groups of HC heterozygotes (those with the ancestral haplotype and those without) and in age-matched controls. These analyses indicate that (i) HC patients with two copies of the ancestral haplotype show significantly more severe expression of the disorder than those with one copy or those without, (ii) HC heterozygotes have partial clinical expression, which may be influenced by the presence of the ancestral haplotype in females but not in males, and (iii) the high population frequency of the HC gene may be the result of the selective advantage conferred by protecting heterozygotes against iron deficiency. 18 refs., 3 tabs.

  6. Evidence that the ancestral haplotype in Australian hemochromatosis patients may be associated with a common mutation in the gene.

    PubMed Central

    Crawford, D H; Powell, L W; Leggett, B A; Francis, J S; Fletcher, L M; Webb, S I; Halliday, J W; Jazwinska, E C

    1995-01-01

    Hemochromatosis (HC) is a common inherited disorder of iron metabolism for which neither the gene nor biochemical defect have yet been identified. The aim of this study was to look for clinical evidence that the predominant ancestral haplotype in Australian patients is associated with a common mutation in the gene. We compared indices of iron metabolism and storage in three groups of HC patients categorized according to the presence of the ancestral haplotype (i.e., patients with two copies, one copy, and no copies of the ancestral haplotype). We also examined iron indices in two groups of HC heterozygotes (those with the ancestral haplotype and those without) and in age-matched controls. These analyses indicate that (i) HC patients with two copies of the ancestral haplotype show significantly more severe expression of the disorder than those with one copy or those without, (ii) HC heterozygotes have partial clinical expression, which may be influenced by the presence of the ancestral haplotype in females but not in males, and (iii) the high population frequency of the HC gene may be the result of the selective advantage conferred by protecting heterozygotes against iron deficiency. PMID:7668262

  7. SNP Array in Hematopoietic Neoplasms: A Review

    PubMed Central

    Song, Jinming; Shao, Haipeng

    2015-01-01

    Cytogenetic analysis is essential for the diagnosis and prognosis of hematopoietic neoplasms in current clinical practice. Many hematopoietic malignancies are characterized by structural chromosomal abnormalities such as specific translocations, inversions, deletions and/or numerical abnormalities that can be identified by karyotype analysis or fluorescence in situ hybridization (FISH) studies. Single nucleotide polymorphism (SNP) arrays offer high-resolution identification of copy number variants (CNVs) and acquired copy-neutral loss of heterozygosity (LOH)/uniparental disomy (UPD) that are usually not identifiable by conventional cytogenetic analysis and FISH studies. As a result, SNP arrays have been increasingly applied to hematopoietic neoplasms to search for clinically-significant genetic abnormalities. A large numbers of CNVs and UPDs have been identified in a variety of hematopoietic neoplasms. CNVs detected by SNP array in some hematopoietic neoplasms are of prognostic significance. A few specific genes in the affected regions have been implicated in the pathogenesis and may be the targets for specific therapeutic agents in the future. In this review, we summarize the current findings of application of SNP arrays in a variety of hematopoietic malignancies with an emphasis on the clinically significant genetic variants. PMID:27600067

  8. An integrative variant analysis pipeline for accurate genotype/haplotype inference in population NGS data.

    PubMed

    Wang, Yi; Lu, James; Yu, Jin; Gibbs, Richard A; Yu, Fuli

    2013-05-01

    Next-generation sequencing is a powerful approach for discovering genetic variation. Sensitive variant calling and haplotype inference from population sequencing data remain challenging. We describe methods for high-quality discovery, genotyping, and phasing of SNPs for low-coverage (approximately 5×) sequencing of populations, implemented in a pipeline called SNPTools. Our pipeline contains several innovations that specifically address challenges caused by low-coverage population sequencing: (1) effective base depth (EBD), a nonparametric statistic that enables more accurate statistical modeling of sequencing data; (2) variance ratio scoring, a variance-based statistic that discovers polymorphic loci with high sensitivity and specificity; and (3) BAM-specific binomial mixture modeling (BBMM), a clustering algorithm that generates robust genotype likelihoods from heterogeneous sequencing data. Last, we develop an imputation engine that refines raw genotype likelihoods to produce high-quality phased genotypes/haplotypes. Designed for large population studies, SNPTools' input/output (I/O) and storage aware design leads to improved computing performance on large sequencing data sets. We apply SNPTools to the International 1000 Genomes Project (1000G) Phase 1 low-coverage data set and obtain genotyping accuracy comparable to that of SNP microarray. PMID:23296920

  9. An Improved Opposition-Based Learning Particle Swarm Optimization for the Detection of SNP-SNP Interactions

    PubMed Central

    Shang, Junliang; Sun, Yan; Li, Shengjun; Liu, Jin-Xing; Zheng, Chun-Hou; Zhang, Junying

    2015-01-01

    SNP-SNP interactions have been receiving increasing attention in understanding the mechanism underlying susceptibility to complex diseases. Though many works have been done for the detection of SNP-SNP interactions, the algorithmic development is still ongoing. In this study, an improved opposition-based learning particle swarm optimization (IOBLPSO) is proposed for the detection of SNP-SNP interactions. Highlights of IOBLPSO are the introduction of three strategies, namely, opposition-based learning, dynamic inertia weight, and a postprocedure. Opposition-based learning not only enhances the global explorative ability, but also avoids premature convergence. Dynamic inertia weight allows particles to cover a wider search space when the considered SNP is likely to be a random one and converges on promising regions of the search space while capturing a highly suspected SNP. The postprocedure is used to carry out a deep search in highly suspected SNP sets. Experiments of IOBLPSO are performed on both simulation data sets and a real data set of age-related macular degeneration, results of which demonstrate that IOBLPSO is promising in detecting SNP-SNP interactions. IOBLPSO might be an alternative to existing methods for detecting SNP-SNP interactions. PMID:26236727

  10. Strong association between microsatellites and an HLA-B, DR haplotype (B18-DR3): Implication for microsatellite evolution

    SciTech Connect

    Crouau-Roy, B.; Bouzekri, N.; Clayton, J.

    1996-09-01

    The HLA haplotype B18-DR3 has a widespread geographical distribution, but has its greatest frequencies in Southern Europe, probably vestigial of the earliest populations of this region, particularly in the Pays Basque and Sardinia. This haplotype is of medical significance, being that most implicated as a factor of risk in insulin-dependent diabetes mellitus. In this study, the closely linked microsatellite markers (TNFa,b,c) in the region of the tumor necrosis factor (TNF) genes have been used in an attempt to subtype this haplotype in the two populations and/or in healthy and diabetic populations. A total of 79 HLA-B18-DR3 haplotypes were analyzed: 54 in Basques (12 from healthy individuals and 42 from diabetics or their first-degree relatives) and 25 in Sardinians (13 from healthy and 13 from diabetic individuals). The TNF haplotype a1-b5-c2 is completely associated with B18-DR3 in both populations. The homogeneity of the B18-DR3 haplotype in two ethnically pure populations implies stability in evolution, which suggest that the mutation rate of these microsatellite markers must be less than is usually assumed (i.e., {approximately} 5x10{sup {minus}6} per site per generation). Such markers should be powerful tools for studying genetic drift and admixture of populations, but it remains to be established whether this stability is a rule for all microsatellites in HLA haplotypes or whether or whether it is restricted to some microsatellites and/or some HLA haplotypes. The population genetics of those microsatellites associated with HLA B18-DR3 was also studied in a random sample of the Basque population. 44 refs., 3 tabs.

  11. Exploring causality via identification of SNPs or haplotypes responsible for a linkage signal

    PubMed Central

    Biernacka, Joanna M; Cordell, Heather J

    2007-01-01

    In a small chromosomal region, a number of polymorphisms may be both linked to and associated with a disease. Distinguishing the potential causal sites from those indirectly associated due to linkage disequilibrium (LD) with a causal site is an important problem. This problem may be approached by determining which of the associations can explain the observed linkage signal. Recently, several methods have been proposed to aid in the identification of disease associated polymorphisms that may explain an observed linkage signal, using genotype data from affected sib pairs (ASPs) [Li et al. [2005] Am. J. Hum. Genet. 76:934–949; Sun et al. [2002] Am. J. Hum. Genet. 70:399–411]. These methods can be used to test the null hypothesis that a candidate single nucleotide polymorphism (SNP) is the sole causal variant in the region, or is in complete LD with the sole causal variant in the region. We extend variations of these methods to test for complete LD between a disease locus and haplotypes composed of two or more tightly linked candidate SNPs. We study properties of the proposed methods by simulation and apply them to type 1 diabetes data for ASPs and their parents at candidate SNP and microsatellite marker loci in the Insulin (INS) gene region. Genet. Epidemiol. 31:2727–740, 2007. © 2007 Wiley-Liss, Inc. PMID:17508343

  12. Association of VIPR-1 gene polymorphisms and haplotypes with egg production in laying quails*

    PubMed Central

    Pu, Yue-jin; Wu, Yan; Xu, Xiao-juan; Du, Jin-ping; Gong, Yan-zhang

    2016-01-01

    The laying quail is a worldwide breed which exhibits high economic value. In our current study, the vasoactive intestinal peptide receptor-1 (VIPR-1) was selected as the candidate gene for identifying traits of egg production. A single nucleotide polymorphism (SNP) detection was performed in 443 individual quails, including 196 quails from the H line, 202 quails from the L line, and 45 wild quails. The SNPs were genotyped using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Two mutations (G373T, A313G) were detected in all the tested quail populations. The associated analysis showed that the SNP genotypes of the VIPR-1 gene were significantly linked with the egg weight of G373T and A313G in 398 quails. The quails with the genotype GG always exhibited the largest egg weight for the two mutations in the H and L lines. Linkage disequilibrium (LD) analysis indicated that G373T and A313G loci showed the weakest LD. Seven main diplotypes from the four main reconstructed haplotypes were observed, indicating a significant association of diplotypes with egg weight. Quails with the h1h2 (GGGT) diplotype always exhibited the smallest egg weight and largest egg number at 20 weeks of age. The overall results suggest that the alterations in quails may be linked with potential major loci or genes affecting reproductive traits. PMID:27487804

  13. Single nucleotide polymorphism and haplotype effects associated with somatic cell score in German Holstein cattle

    PubMed Central

    2014-01-01

    Background To better understand the genetic determination of udder health, we performed a genome-wide association study (GWAS) on a population of 2354 German Holstein bulls for which daughter yield deviations (DYD) for somatic cell score (SCS) were available. For this study, we used genetic information of 44 576 informative single nucleotide polymorphisms (SNPs) and 11 725 inferred haplotype blocks. Results When accounting for the sub-structure of the analyzed population, 16 SNPs and 10 haplotypes in six genomic regions were significant at the Bonferroni threshold of P ≤ 1.14 × 10-6. The size of the identified regions ranged from 0.05 to 5.62 Mb. Genomic regions on chromosomes 5, 6, 18 and 19 coincided with known QTL affecting SCS, while additional genomic regions were found on chromosomes 13 and X. Of particular interest is the region on chromosome 6 between 85 and 88 Mb, where QTL for mastitis traits and significant SNPs for SCS in different Holstein populations coincide with our results. In all identified regions, except for the region on chromosome X, significant SNPs were present in significant haplotypes. The minor alleles of identified SNPs on chromosomes 18 and 19, and the major alleles of SNPs on chromosomes 6 and X were favorable for a lower SCS. Differences in somatic cell count (SCC) between alternative SNP alleles reached 14 000 cells/mL. Conclusions The results support the polygenic nature of the genetic determination of SCS, confirm the importance of previously reported QTL, and provide evidence for the segregation of additional QTL for SCS in Holstein cattle. The small size of the regions identified here will facilitate the search for causal genetic variations that affect gene functions. PMID:24898131

  14. Forensic Spanish allele and haplotype database for a 17 X-STR panel.

    PubMed

    Prieto-Fernández, Endika; Núñez, Carolina; Baeta, Miriam; Jiménez-Moreno, Susana; Martínez-Jarreta, Begoña; de Pancorbo, Marian M

    2016-09-01

    The currently developed 17 X-STR panel (DXS8378, DXS9898, DXS7133, GATA31E08, GATA172D05, DXS6801, DXS7423, DXS6809, DXS6799, DXS7132, DXS9902, DXS6800, DXS6789, DXS10075, DXS10079, DXS6807, and DXS6803) offers a highly discriminative tool for forensic identification and kinship testing. With the aim of providing a global Spanish population X-STR database, we present haplotype and allele frequencies and parameters of forensic interest for the 17 X-STR panel obtained from 593 unrelated individuals from Alicante, Aragon, the Basque Country, Andalusia, Galicia, Madrid, and Barcelona that represent the most populated regions of the Spanish Peninsular territory. The seven populations were compared to test possible population genetic substructures. The lack of significant differences among the studied Spanish populations supports the use of the allele and haplotype frequency database presented herein as a global Spanish population sample useful for statistical evaluation in forensic casework. After conducting the LD plots derived from HapMap and pairwise linkage disequilibrium tests, DXS7132, DXS10075, and DXS10079 markers were included in a cluster and haplotype frequencies were calculated. The improvement in the forensic parameters for the Spanish population using 17 X-STRs in comparison to the previous 10 X-STR allele frequencies database is also shown. PMID:27388427

  15. Disclosing the Genetic Structure of Brazil through Analysis of Male Lineages with Highly Discriminating Haplotypes

    PubMed Central

    Palha, Teresinha; Gusmão, Leonor; Ribeiro-Rodrigues, Elzemar; Guerreiro, João Farias; Ribeiro-dos-Santos, Ândrea; Santos, Sidney

    2012-01-01

    In a large variety of genetic studies, probabilistic inferences are made based on information available in population databases. The accuracy of the estimates based on population samples are highly dependent on the number of chromosomes being analyzed as well as the correct representation of the reference population. For frequency calculations the size of a database is especially critical for haploid markers, and for countries with complex admixture histories it is important to assess possible substructure effects that can influence the coverage of the database. Aiming to establish a representative Brazilian population database for haplotypes based on 23 Y chromosome STRs, more than 2,500 Y chromosomes belonging to Brazilian, European and African populations were analyzed. No matter the differences in the colonization history of the five geopolitical regions that currently exist in Brazil, for the Y chromosome haplotypes of the 23 studied Y-STRs, a lack of genetic heterogeneity was found, together with a predominance of European male lineages in all regions of the country. Therefore, if we do not consider the diverse Native American or Afro-descendent isolates, which are spread through the country, a single Y chromosome haplotype frequency database will adequately represent the urban populations in Brazil. In comparison to the most commonly studied group of 17 Y-STRs, the 23 markers included in this work allowed a high discrimination capacity between haplotypes from non-related individuals within a population and also increased the capacity to discriminate between paternal relatives. Nevertheless, the expected haplotype mutation rate is still not enough to distinguish the Y chromosome profiles of paternally related individuals. Indeed, even for rapidly mutating Y-STRs, a very large number of markers will be necessary to differentiate male lineages from paternal relatives. PMID:22808085

  16. Enhancing the mathematical properties of new haplotype homozygosity statistics for the detection of selective sweeps.

    PubMed

    Garud, Nandita R; Rosenberg, Noah A

    2015-06-01

    Soft selective sweeps represent an important form of adaptation in which multiple haplotypes bearing adaptive alleles rise to high frequency. Most statistical methods for detecting selective sweeps from genetic polymorphism data, however, have focused on identifying hard selective sweeps in which a favored allele appears on a single haplotypic background; these methods might be underpowered to detect soft sweeps. Among exceptions is the set of haplotype homozygosity statistics introduced for the detection of soft sweeps by Garud et al. (2015). These statistics, examining frequencies of multiple haplotypes in relation to each other, include H12, a statistic designed to identify both hard and soft selective sweeps, and H2/H1, a statistic that conditional on high H12 values seeks to distinguish between hard and soft sweeps. A challenge in the use of H2/H1 is that its range depends on the associated value of H12, so that equal H2/H1 values might provide different levels of support for a soft sweep model at different values of H12. Here, we enhance the H12 and H2/H1 haplotype homozygosity statistics for selective sweep detection by deriving the upper bound on H2/H1 as a function of H12, thereby generating a statistic that normalizes H2/H1 to lie between 0 and 1. Through a reanalysis of resequencing data from inbred lines of Drosophila, we show that the enhanced statistic both strengthens interpretations obtained with the unnormalized statistic and leads to empirical insights that are less readily apparent without the normalization. PMID:25891325

  17. Assigning linkage haplotypes from parent and progeny genotypes

    SciTech Connect

    Nejati-Javaremi, A.; Smith, C.

    1996-04-01

    Given the genotypes of parents and progeny, their haplotypes over several or many linked loci can be easily assigned by listing the allele type at each locus along the haplotype known to be from each parent. Only a small number (5-10) of progeny per family is usually needed to assign the parental and progeny haplotypes. Any gaps left in the haplotypes may be filled in from the assigned haplotypes of relatives. The process is facilitated by having multiple alleles at the loci and by using more linked loci in the haplotype and with more progeny from the mating. Crossover haplotypes in the progeny can be identified by their being unique or uncommon, and the crossover point can often be detected if the locus linkage map order is known. The haplotyping method applies to outbreeding populations in plants, animals, and man, as well as to traditional experimental crosses of inbred lines. The method also applies to half-sib families, whether the genotype of the mates are known or unknown. The haplotyping procedure is already used in linkage analysis but does not seem to have been published. It should be useful in teaching and in genetic applications of haplotypes. 15 refs., 5 tabs.

  18. An improved preprocessing algorithm for haplotype inference by pure parsimony.

    PubMed

    Choi, Mun-Ho; Kang, Seung-Ho; Lim, Hyeong-Seok

    2014-08-01

    The identification of haplotypes, which encode SNPs in a single chromosome, makes it possible to perform a haplotype-based association test with disease. Given a set of genotypes from a population, the process of recovering the haplotypes, which explain the genotypes, is called haplotype inference (HI). We propose an improved preprocessing method for solving the haplotype inference by pure parsimony (HIPP), which excludes a large amount of redundant haplotypes by detecting some groups of haplotypes that are dispensable for optimal solutions. The method uses only inclusion relations between groups of haplotypes but dramatically reduces the number of candidate haplotypes; therefore, it causes the computational time and memory reduction of real HIPP solvers. The proposed method can be easily coupled with a wide range of optimization methods which consider a set of candidate haplotypes explicitly. For the simulated and well-known benchmark datasets, the experimental results show that our method coupled with a classical exact HIPP solver run much faster than the state-of-the-art solver and can solve a large number of instances that were so far unaffordable in a reasonable time. PMID:25152045

  19. Genotypes and haplotypes of the methyl-CpG-binding domain 2 modify breast cancer risk dependent upon menopausal status

    PubMed Central

    Zhu, Yong; Brown, Heather N; Zhang, Yawei; Holford, Theodore R; Zheng, Tongzhang

    2005-01-01

    Introduction MBD2, the gene encoding methyl-CpG-binding domain (MBD)2, is a major methylation related gene and functions as a transcriptional repressor that can specifically bind to the methylated regions of other genes. MBD2 may also mediate gene activation because of its potential DNA demethylase activity. The present case-control study investigated associations between two single nucleotide polymorphisms (SNPs) in the MBD2 gene and breast cancer risk. Methods DNA samples from 393 Caucasian patients with breast cancer (cases) and 436 matched control individuals, collected in a recently completed breast cancer case–control study conducted in Connecticut, were included in the study. Because no coding SNPs were found in the MBD2 gene, one SNP in the noncoding exon (rs1259938) and another in the intron 3 (rs609791) were genotyped. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate cancer risk associated with the variant genotypes and the reconstructed haplotypes. Results The variant genotypes at both SNP loci were significantly associated with reduced risk among premenopausal women (OR = 0.41 for rs1259938; OR = 0.54 for rs609791). Further haplotype analyses showed that the two rare haplotypes (A-C and A-G) were significantly associated with reduced breast cancer risk (OR = 0.40, 95% CI = 0.20–0.83 for A-C; OR = 0.47, 95% CI = 0.26–0.84 for A-G) in premenopausal women. No significant associations were detected in the postmenopausal women and the whole population. Conclusion Our results demonstrate a role for the MBD2 gene in breast carcinogenesis in premenopausal women. These findings suggest that genetic variations in methylation related genes may potentially serve as a biomarker in risk estimates for breast cancer. PMID:16168120

  20. Analysis of DNA haplotypes suggests a genetic predisposition to trisomy 21 associated with DNA sequences on chromosome 21.

    PubMed Central

    Antonarakis, S E; Kittur, S D; Metaxotou, C; Watkins, P C; Patel, A S

    1985-01-01

    To test the hypothesis that there is a genetic predisposition to nondisjunction and trisomy 21 associated with DNA sequences on chromosome 21, we used DNA polymorphism haplotypes for chromosomes 21 to examine the distribution of different chromosomes 21 in Down syndrome and control families from the same ethnic group. The chromosomes 21 from 20 Greek families with a Down syndrome child and 27 control Greek families have been examined for DNA polymorphism haplotypes by using four common polymorphic sites adjacent to two closely linked single-copy DNA sequences (namely pW228C and pW236B), which map somewhere near the proximal long arm of chromosome 21. Three haplotypes, +, +---, and - with respective frequencies of 43/108, 24/108, and 23/108, account for the majority of chromosomes 21 in the control families. However, haplotype - was found to be much more commonly associated with chromosomes 21 that underwent nondisjunction in the Down syndrome families (frequency of 21/50; X2 for the two distributions is 9.550; P = 0.023; degrees of freedom, 3). The two populations (control and trisomic families) did not differ in the distribution of haplotypes for two DNA polymorphisms on chromosome 17. The data from this initial study suggest that the chromosome 21, which is marked in Greeks with haplotype - for the four above described polymorphic sites, is found more commonly in chromosomes that participate in nondisjunction than in controls. We propose an increased tendency for nondisjunction due to DNA sequences associated with a subset of chromosomes 21 bearing this haplotype. Images PMID:2987923

  1. HLA class II linkage disequilibrium and haplotype evolution in the Cayapa Indians of Ecuador

    SciTech Connect

    Trachtenberg, E.A.; Erlich, H.A.; Klitz, W.

    1995-08-01

    DNA-based typing of the HLA class II loci in a sample of the Cayapa Indians of Ecuador reveals several lines of evidence that selection has operated to maintain and to diversify the existing level of polymorphism in the class II region. As has been noticed for other Native American groups, the overall level of polymorphism at the DRB1, DQA1, DQB1, and DPB1 loci is reduced relative to that found in other human populations. Nonetheless, the relative eveness in the distribution of allele frequencies at each of the four loci points to the role of balancing selection in the maintenance of the polymorphism. The DQA1 and DQB1 loci, in particular, have near-maximum departures from the neutrality model, which suggests that balancing selection has been especially strong in these cases. Several novel DQA1-DQB1 haplotypes and the discovery of a new DRB1 allele demonstrate an evolutionary tendency favoring the diversification of class II alleles and haplotypes. The recombination interval between the centromeric DPB1 locus and the other class II loci will, in the absence of other forces such as selection, reduce disequilibrium across this region. However, nearly all common alleles were found to be part of DR-DP haplotypes in strong disequilibrium, consistent with the recent action of selection acting on these haplotypes in the Cayapa. 50 refs., 3 figs., 3 tabs.

  2. Haplotype data for 23 Y-chromosome markers in a reference sample from Bosnia and Herzegovina

    PubMed Central

    Kovačević, Lejla; Fatur-Cerić, Vera; Hadžić, Negra; Čakar, Jasmina; Primorac, Dragan; Marjanović, Damir

    2013-01-01

    Aim To detect polymorphisms of 23 Y-chromosomal short tandem repeat (STR) loci, including 6 new loci, in a reference database of male population of Bosnia and Herzegovina, as well as to assess the importance of increasing the number of Y-STR loci utilized in forensic DNA analysis. Methods The reference sample consisted of 100 healthy, unrelated men originating from Bosnia and Herzegovina. Sample collection using buccal swabs was performed in all geographical regions of Bosnia and Herzegovina in the period from 2010 to 2011. DNA samples were typed for 23 Y STR loci, including 6 new loci: DYS576, DYS481, DYS549, DYS533, DYS570, and DYS643, which are included in the new PowerPlex® Y 23 amplification kit. Results The absolute frequency of generated haplotypes was calculated and results showed that 98 samples had unique Y 23 haplotypes, and that only two samples shared the same haplotype. The most polymorphic locus was DYS418, with 14 detected alleles and the least polymorphic loci were DYS389I, DYS391, DYS437, and DYS393. Conclusion This study showed that by increasing the number of highly polymorphic Y STR markers, to include those tested in our analysis, leads to a reduction of repeating haplotypes, which is very important in the application of forensic DNA analysis. PMID:23771760

  3. Association between vitamin D receptor polymorphisms and haplotypes with pulmonary tuberculosis

    PubMed Central

    SALIMI, SAEEDEH; FARAJIAN-MASHHADI, FARZANEH; ALAVI-NAINI, ROYA; TALEBIAN, GOLBARG; NAROOIE-NEJAD, MEHRNAZ

    2015-01-01

    The vitamin D receptor (VDR) is an important factor in activating immune response in different infectious diseases. The aim of the present study was to investigate the association between the VDR gene polymorphisms and pulmonary tuberculosis (PTB). The case control study was performed on 120 PTB patients and 131 healthy controls. Genetic analysis was performed by polymerase chain reaction and the restriction fragment length polymorphism method. The VDR Fok1 Ff genotype was associated with TB and the risk of PTB was two times higher in individuals with the Ff genotype. A higher frequency of f allele was observed in PTB patients and therefore, the f allele may be a risk factor for PTB susceptibility. There were no associations between the Taq1 and Bsm1 polymorphisms and PTB. In addition, haplotype analysis showed that the f-T-B and f-t-b haplotypes (Fok1, Taq1 and Bsm1) may have the potential to increase PTB susceptibility. In conclusion, the Ff genotype and f allele of the VDR Fok1 polymorphism were associated with PTB susceptibility. In addition, the f-T-B and f-t-b haplotypes may be the susceptible haplotypes for PTB. PMID:26075071

  4. Phylogenetic nomenclature and evolution of mannose-binding lectin (MBL2) haplotypes

    PubMed Central

    2010-01-01

    Background Polymorphisms of the mannose-binding lectin gene (MBL2) affect the concentration and functional efficiency of the protein. We recently used haplotype-specific sequencing to identify 23 MBL2 haplotypes, associated with enhanced susceptibility to several diseases. Results In this work, we applied the same method in 288 and 470 chromosomes from Gabonese and European adults, respectively, and found three new haplotypes in the last group. We propose a phylogenetic nomenclature to standardize MBL2 studies and found two major phylogenetic branches due to six strongly linked polymorphisms associated with high MBL production. They presented high Fst values and were imbedded in regions with high nucleotide diversity and significant Tajima's D values. Compared to others using small sample sizes and unphased genotypic data, we found differences in haplotyping, frequency estimation, Fu and Li's D* and Fst results. Conclusion Using extensive testing for selective neutrality, we confirmed that stochastic evolutionary factors have had a major role in shaping this polymorphic gene worldwide. PMID:20465856

  5. Dispersion of human Y chromosome haplotypes based on five microsatellites in global populations.

    PubMed

    Deka, R; Jin, L; Shriver, M D; Yu, L M; Saha, N; Barrantes, R; Chakraborty, R; Ferrell, R E

    1996-12-01

    We have analyzed five microsatellite loci from the nonrecombining portion of the human Y chromosome in 15 diverse human populations to evaluate their usefulness in the reconstruction of human evolution and early male migrations. The results show that, in general, most populations have the same set of the most frequent alleles at these loci. Hypothetical ancestral haplotypes, reconstructed on the basis of these alleles and their close derivatives, are shared by multiple populations across racial and geographical boundaries. A network of the observed haplotypes is characterized by a lack of clustering of geographically proximal populations. In spite of this, few distinct clusters of closely related populations emerged in the network, which are associated with population-specific alleles. A tree based on allele frequencies also shows similar results. Lack of haplotypic structure associated with the presumed ancestral haplotypes consisting of individuals from almost all populations indicate a recent common ancestry and/or extensive male migration during human evolutionary history. The convergent nature of microsatellite mutation confounds population relationships. Optimum resolution of Y chromosome evolution will require the use of additional microsatellite loci and diallelic genetic markers with lower mutation rates. PMID:8973912

  6. Haplotype test reveals departure from neutrality in a segment of the white gene of Drosophila melanogaster

    SciTech Connect

    Kirby, D.A.; Stephan, W.

    1995-12-01

    Restriction map studies previously revealed extensive linkage disequilibria in the transcriptional unit of the white locus in natural Drosophila melanogaster populations. To understand the causes of these disequilibria, we sequenced a 4722-bp region of the white gene from 15 lines of D. melanogaster and 1 line of Drosophila simulans. Statistical tests applied to the entire 4722-bp region do not reject neutrality. In contrast, a test for high-frequency haplotypes ({open_quotes}Haplotype test{close_quotes}) revealed an 834-bp segment, encompassing the 3{prime} end of intron 1 to the 3{prime} end of intron 2, in which the structure of variation deviates significantly from the predictions of a neutral equilibrium model. The variants in this 834-bp segment segregate as single haplotype blocks. We propose that these unusually large haplotype blocks are due to positive selection on polymorphisms within the white gene, including a replacement polymorphism, Arg{yields}Leu, within this segment. 45 refs., 4 figs., 1 tab.

  7. Patterns of haplotypes for 92 cystic fibrosis mutations: Variability, association and recurrence

    SciTech Connect

    Morral, N.; Llevadot, R.; Estivill, X.

    1994-09-01

    Most CFTR mutations are very uncommon among the cystic fibrosis population, with frequencies of less than 1%, and many are found only in specific areas. We have analyzed 92 CF mutations for several markers (4 microsatellites and 3 other polymorphisms) scattered in the CFTR gene. Haplotypes associated with these mutations can be used as a framework in the screening of chromosomes carrying unknown mutations. The association between mutation and haplotype reduces the number of mutations it is necessary to search for to a maximum of 16 for the same haplotype. Only mutations {triangle}F508, G542X and N1303K are associated with more than one haplotype as a result of slippage at more than one microsatellite loci, suggesting that these three are the most ancient CF mutations. Recurrence has been found for at least 7 mutations: H199Y, R347P, L558S, R553X, 2184insA, 3272-26A{r_arrow}G, 3849+10kbC{r_arrow}T and R1162X. Also microsatellite analysis of chromosomes of several ethnic origins (Czech, Italian, Russian, Slovac and Spanish) suggested that possibility of three or more independent origins for mutations R334W, R347P, R1162X, and 3849+10kbC{r_arrow}T, which was confirmed by analysis of markers flanking these mutations.

  8. Identification of the ancestral haplotype for apolipoprotein B suggests an African origin of Homo sapiens sapiens and traces their subsequent migration to Europe and the Pacific

    SciTech Connect

    Rapacz, J.; Hasler-Rapacz, J.O. ); Chen, L.; Wu, Mingjiuan; Schumaker, V.N. ); Butler-Brunner, E.; Butler, R. )

    1991-02-15

    The probable ancestral haplotype for human apolipoprotein B (apoB) has been identified through immunological analysis of chimpanzee and gorilla serum and sequence analysis of their DNA. Moreover, the frequency of this ancestral apoB haplotype among different human populations provides strong support for the African origin of Homo sapiens sapiens and their subsequent migration from Africa to Europe and to the Pacific. The approach used here for the identification of the ancestral human apoB haplotype is likely to be applicable to many other genes.

  9. Identification of the ancestral haplotype for apolipoprotein B suggests an African origin of Homo sapiens sapiens and traces their subsequent migration to Europe and the Pacific.

    PubMed Central

    Rapacz, J; Chen, L; Butler-Brunner, E; Wu, M J; Hasler-Rapacz, J O; Butler, R; Schumaker, V N

    1991-01-01

    The probable ancestral haplotype for human apolipoprotein B (apoB) has been identified through immunological analysis of chimpanzee and gorilla serum and sequence analysis of their DNA. Moreover, the frequency of this ancestral apoB haplotype among different human populations provides strong support for the African origin of Homo sapiens sapiens and their subsequent migration from Africa to Europe and to the Pacific. The approach used here for the identification of the ancestral human apoB haplotype is likely to be applicable to many other genes. PMID:1996341

  10. Identification of the ancestral haplotype for apolipoprotein B suggests an African origin of Homo sapiens sapiens and traces their subsequent migration to Europe and the Pacific.

    PubMed

    Rapacz, J; Chen, L; Butler-Brunner, E; Wu, M J; Hasler-Rapacz, J O; Butler, R; Schumaker, V N

    1991-02-15

    The probable ancestral haplotype for human apolipoprotein B (apoB) has been identified through immunological analysis of chimpanzee and gorilla serum and sequence analysis of their DNA. Moreover, the frequency of this ancestral apoB haplotype among different human populations provides strong support for the African origin of Homo sapiens sapiens and their subsequent migration from Africa to Europe and to the Pacific. The approach used here for the identification of the ancestral human apoB haplotype is likely to be applicable to many other genes. PMID:1996341

  11. Possible Positive Selection for an Arsenic-Protective Haplotype in Humans

    PubMed Central

    Schlebusch, Carina M.; Lewis, Cecil M.; Vahter, Marie; Engström, Karin; Tito, Raúl Y.; Obregón-Tito, Alexandra J.; Huerta, Doris; Polo, Susan I.; Medina, Ángel C.; Brutsaert, Tom D.; Concha, Gabriela; Jakobsson, Mattias

    2012-01-01

    Background: Arsenic in drinking water causes severe health effects. Indigenous people in the South American Andes have likely lived with arsenic-contaminated drinking water for thousands of years. Inhabitants of San Antonio de los Cobres (SAC) in the Argentinean highlands generally carry an AS3MT (the major arsenic-metabolizing gene) haplotype associated with reduced health risks due to rapid arsenic excretion and lower urinary fraction of the monomethylated metabolite. Objectives: We hypothesized an adaptation to high-arsenic living conditions via a possible positive selection for protective AS3MT variants and compared AS3MT haplotype frequencies among different indigenous groups. Methods: Indigenous groups we evaluated were a) inhabitants of SAC and villages near Salta in northern Argentina (n = 346), b) three Native American populations from the Human Genome Diversity Project (HGDP; n = 25), and c) five Peruvian populations (n = 97). The last two groups have presumably lower historical exposure to arsenic. Results: We found a significantly higher frequency of the protective AS3MT haplotype in the SAC population (68.7%) compared with the HGDP (14.3%, p < 0.001, Fisher exact test) and Peruvian (50.5%, p < 0.001) populations. Genome-wide microsatellite (n = 671) analysis showed no detectable level of population structure between SAC and Peruvian populations (measure of population differentiation FST = 0.006) and low levels of structure between SAC and HGDP populations (FST < 0.055 for all pairs of populations compared). Conclusions: Because population stratification seems unlikely to explain the differences in AS3MT haplotype frequencies, our data raise the possibility that, during a few thousand years, natural selection for tolerance to the environmental stressor arsenic may have increased the frequency of protective variants of AS3MT. Further studies are needed to investigate this hypothesis. PMID:23070617

  12. Distribution of HLA haplotypes across Japanese Archipelago: similarity, difference and admixture.

    PubMed

    Nakaoka, Hirofumi; Inoue, Ituro

    2015-11-01

    The human leukocyte antigen (HLA) region is the most polymorphic region in the human genome. The polymorphic nature of the HLA region is thought to have been shaped from balancing selection. The complex migration events during the Out-of-Africa expansion have influenced geographic patterns of HLA allele frequencies and diversities across present-day human populations. Differences in the HLA allele frequency may contribute geographic differences in the susceptibility to many diseases, such as infectious, autoimmune and metabolic diseases. Here we briefly reviewed characteristics of frequency distribution of HLA alleles and haplotypes in Japanese population. A large part of HLA alleles and haplotypes that are common in Japanese are shared with neighboring Asian populations. The differentiations in HLA alleles and haplotypes across Japanese regional populations may provide clues to model for peopling of Japanese Archipelago and for design of genetic association studies. Finally, we introduce recent topics that new HLA alleles derived from ancient admixtures with Neanderthals and Denisovans are thought to have played an important role in the adaptation of modern humans to local pathogens during Out-of-Africa expansion. PMID:26202576

  13. Vitis Phylogenomics: Hybridization Intensities from a SNP Array Outperform Genotype Calls

    PubMed Central

    Miller, Allison J.; Matasci, Naim; Schwaninger, Heidi; Aradhya, Mallikarjuna K.; Prins, Bernard; Zhong, Gan-Yuan; Simon, Charles; Buckler, Edward S.; Myles, Sean

    2013-01-01

    Understanding relationships among species is a fundamental goal of evolutionary biology. Single nucleotide polymorphisms (SNPs) identified through next generation sequencing and related technologies enable phylogeny reconstruction by providing unprecedented numbers of characters for analysis. One approach to SNP-based phylogeny reconstruction is to identify SNPs in a subset of individuals, and then to compile SNPs on an array that can be used to genotype additional samples at hundreds or thousands of sites simultaneously. Although powerful and efficient, this method is subject to ascertainment bias because applying variation discovered in a representative subset to a larger sample favors identification of SNPs with high minor allele frequencies and introduces bias against rare alleles. Here, we demonstrate that the use of hybridization intensity data, rather than genotype calls, reduces the effects of ascertainment bias. Whereas traditional SNP calls assess known variants based on diversity housed in the discovery panel, hybridization intensity data survey variation in the broader sample pool, regardless of whether those variants are present in the initial SNP discovery process. We apply SNP genotype and hybridization intensity data derived from the Vitis9kSNP array developed for grape to show the effects of ascertainment bias and to reconstruct evolutionary relationships among Vitis species. We demonstrate that phylogenies constructed using hybridization intensities suffer less from the distorting effects of ascertainment bias, and are thus more accurate than phylogenies based on genotype calls. Moreover, we reconstruct the phylogeny of the genus Vitis using hybridization data, show that North American subgenus Vitis species are monophyletic, and resolve several previously poorly known relationships among North American species. This study builds on earlier work that applied the Vitis9kSNP array to evolutionary questions within Vitis vinifera and has general

  14. Allele-Specific Amplification in Cancer Revealed by SNP Array Analysis

    PubMed Central

    2005-01-01

    Amplification, deletion, and loss of heterozygosity of genomic DNA are hallmarks of cancer. In recent years a variety of studies have emerged measuring total chromosomal copy number at increasingly high resolution. Similarly, loss-of-heterozygosity events have been finely mapped using high-throughput genotyping technologies. We have developed a probe-level allele-specific quantitation procedure that extracts both copy number and allelotype information from single nucleotide polymorphism (SNP) array data to arrive at allele-specific copy number across the genome. Our approach applies an expectation-maximization algorithm to a model derived from a novel classification of SNP array probes. This method is the first to our knowledge that is able to (a) determine the generalized genotype of aberrant samples at each SNP site (e.g., CCCCT at an amplified site), and (b) infer the copy number of each parental chromosome across the genome. With this method, we are able to determine not just where amplifications and deletions occur, but also the haplotype of the region being amplified or deleted. The merit of our model and general approach is demonstrated by very precise genotyping of normal samples, and our allele-specific copy number inferences are validated using PCR experiments. Applying our method to a collection of lung cancer samples, we are able to conclude that amplification is essentially monoallelic, as would be expected under the mechanisms currently believed responsible for gene amplification. This suggests that a specific parental chromosome may be targeted for amplification, whether because of germ line or somatic variation. An R software package containing the methods described in this paper is freely available at http://genome.dfci.harvard.edu/~tlaframb/PLASQ. PMID:16322765

  15. A Bayesian Framework for SNP Identification

    SciTech Connect

    Webb-Robertson, Bobbie-Jo M.; Havre, Susan L.; Payne, Deborah A.

    2005-07-01

    Current proteomics techniques, such as mass spectrometry, focus on protein identification, usually ignoring most types of modifications beyond post-translational modifications, with the assumption that only a small number of peptides have to be matched to a protein for a positive identification. However, not all proteins are being identified with current techniques and improved methods to locate points of mutation are becoming a necessity. In the case when single-nucleotide polymorphisms (SNPs) are observed, brute force is the most common method to locate them, quickly becoming computationally unattractive as the size of the database associated with the model organism grows. We have developed a Bayesian model for SNPs, BSNP, incorporating evolutionary information at both the nucleotide and amino acid levels. Formulating SNPs as a Bayesian inference problem allows probabilities of interest to be easily obtained, for example the probability of a specific SNP or specific type of mutation over a gene or entire genome. Three SNP databases were observed in the evaluation of the BSNP model; the first SNP database is a disease specific gene in human, hemoglobin, the second is also a disease specific gene in human, p53, and the third is a more general SNP database for multiple genes in mouse. We validate that the BSNP model assigns higher posterior probabilities to the SNPs defined in all three separate databases than can be attributed to chance under specific evolutionary information, for example the amino acid model described by Majewski and Ott in conjunction with either the four-parameter nucleotide model by Bulmer or seven-parameter nucleotide model by Majewski and Ott.

  16. Haplotype kinship for three populations of the Goettingen minipig

    PubMed Central

    Flury, Christine; Weigend, Steffen; Ding, Xiangdong; Täubert, Helge; Simianer, Henner

    2007-01-01

    To overcome limitations of diversity measures applied to livestock breeds marker based estimations of kinship within and between populations were proposed. This concept was extended from the single locus consideration to chromosomal segments of a given length in Morgan. Algorithms for the derivation of haplotype kinship were suggested and the behaviour of marker based haplotype kinship was investigated theoretically. In the present study the results of the first practical application of this concept are presented. Full sib pairs of three sub-populations of the Goettingen minipig were genotyped for six chromosome segments. After haplotype reconstruction the haplotypes were compared and mean haplotype kinships were estimated within and between populations. Based on haplotype kinships a distance measure is proposed which is approximatively linear with the number of generations since fission. The haplotype kinship distances, the respective standard errors and the pedigree-based expected values are presented and are shown to reflect the true population history better than distances based on single-locus kinships. However the marker estimated haplotype kinship reveals variable among segments. This leads to high standard errors of the respective distances. Possible reasons for this phenomenon are discussed and a pedigree-based approach to correct for identical haplotypes which are not identical by descent is proposed. PMID:17306199

  17. Genomic evolution in domestic cattle: ancestral haplotypes and healthy beef.

    PubMed

    Williamson, Joseph F; Steele, Edward J; Lester, Susan; Kalai, Oscar; Millman, John A; Wolrige, Lindsay; Bayard, Dominic; McLure, Craig; Dawkins, Roger L

    2011-05-01

    We have identified numerous Ancestral Haplotypes encoding a 14-Mb region of Bota C19. Three are frequent in Simmental, Angus and Wagyu and have been conserved since common progenitor populations. Others are more relevant to the differences between these 3 breeds including fat content and distribution in muscle. SREBF1 and Growth Hormone, which have been implicated in the production of healthy beef, are included within these haplotypes. However, we conclude that alleles at these 2 loci are less important than other sequences within the haplotypes. Identification of breeds and hybrids is improved by using haplotypes rather than individual alleles. PMID:21338665

  18. Bayesian Modeling of Haplotype Effects in Multiparent Populations

    PubMed Central

    Zhang, Zhaojun; Wang, Wei; Valdar, William

    2014-01-01

    A general Bayesian model, Diploffect, is described for estimating the effects of founder haplotypes at quantitative trait loci (QTL) detected in multiparental genetic populations; such populations include the Collaborative Cross (CC), Heterogeneous Socks (HS), and many others for which local genetic variation is well described by an underlying, usually probabilistically inferred, haplotype mosaic. Our aim is to provide a framework for coherent estimation of haplotype and diplotype (haplotype pair) effects that takes into account the following: uncertainty in haplotype composition for each individual; uncertainty arising from small sample sizes and infrequently observed haplotype combinations; possible effects of dominance (for noninbred subjects); genetic background; and that provides a means to incorporate data that may be incomplete or has a hierarchical structure. Using the results of a probabilistic haplotype reconstruction as prior information, we obtain posterior distributions at the QTL for both haplotype effects and haplotype composition. Two alternative computational approaches are supplied: a Markov chain Monte Carlo sampler and a procedure based on importance sampling of integrated nested Laplace approximations. Using simulations of QTL in the incipient CC (pre-CC) and Northport HS populations, we compare the accuracy of Diploffect, approximations to it, and more commonly used approaches based on Haley–Knott regression, describing trade-offs between these methods. We also estimate effects for three QTL previously identified in those populations, obtaining posterior intervals that describe how the phenotype might be affected by diplotype substitutions at the modeled locus. PMID:25236455

  19. Allele diversity for abiotic stress responsive candidate genes in chickpea reference set using gene based SNP markers

    PubMed Central

    Roorkiwal, Manish; Nayak, Spurthi N.; Thudi, Mahendar; Upadhyaya, Hari D.; Brunel, Dominique; Mournet, Pierre; This, Dominique; Sharma, Prakash C.; Varshney, Rajeev K.

    2014-01-01

    Chickpea is an important food legume crop for the semi-arid regions, however, its productivity is adversely affected by various biotic and abiotic stresses. Identification of candidate genes associated with abiotic stress response will help breeding efforts aiming to enhance its productivity. With this objective, 10 abiotic stress responsive candidate genes were selected on the basis of prior knowledge of this complex trait. These 10 genes were subjected to allele specific sequencing across a chickpea reference set comprising 300 genotypes including 211 genotypes of chickpea mini core collection. A total of 1.3 Mbp sequence data were generated. Multiple sequence alignment (MSA) revealed 79 SNPs and 41 indels in nine genes while the CAP2 gene was found to be conserved across all the genotypes. Among 10 candidate genes, the maximum number of SNPs (34) was observed in abscisic acid stress and ripening (ASR) gene including 22 transitions, 11 transversions and one tri-allelic SNP. Nucleotide diversity varied from 0.0004 to 0.0029 while polymorphism information content (PIC) values ranged from 0.01 (AKIN gene) to 0.43 (CAP2 promoter). Haplotype analysis revealed that alleles were represented by more than two haplotype blocks, except alleles of the CAP2 and sucrose synthase (SuSy) gene, where only one haplotype was identified. These genes can be used for association analysis and if validated, may be useful for enhancing abiotic stress, including drought tolerance, through molecular breeding. PMID:24926299

  20. Generation of SNP datasets for orangutan population genomics using improved reduced-representation sequencing and direct comparisons of SNP calling algorithms

    PubMed Central

    2014-01-01

    Our enhanced iRRL approach greatly facilitates genotyping-by-sequencing and thus direct estimates of allele frequencies. Our direct comparison of three commonly used SNP callers emphasizes the need to question the accuracy of SNP and genotype calling, as we obtained considerably different SNP datasets depending on caller algorithms, sequencing depths and filtering criteria. These differences affected scans for signatures of natural selection, but will also exert undue influences on demographic inferences. This study presents the first effort to generate a population genomic dataset for wild-born orangutans with known population provenance. PMID:24405840

  1. Hereditary tyrosinemia type 1: Strong association with haplotype 6 in French Canadians permits simple carrier detection and prenatal diagnosis

    SciTech Connect

    Demers, S.I.; Phaneuf, D.; Tanguay, R.M. )

    1994-08-01

    Hereditary tyrosinemia type 1 (HT1), a severe inborn error of tyrosine catabolism, is caused by deficiency of the terminal enzyme, fumarylacetoacetate hydrolase (FAH). The highest reported frequency of HT1 is in the French Canadian population, especially in the Saguenay-Lac-St-Jean region. Using human FAH cDNA probes, the authors have identified 10 haplotypes with TaqI, KpnI, RsaI, BglII, and MspI RFLPs in 118 normal chromosomes from the French Canadian population. Interestingly, in 29 HT1 children, a prevalent haplotype, haplotype 6, was found to be strongly associated with the disease, at a frequency of 90% of alleles, as compared with [approximately] 18% in 35 control individuals. This increased to 96% in the 24 patients originating from Saguenay-Lac-St-Jean. These results suggest that one or only a few prevailing mutations are responsible for most of the HT1 cases in Saguenay-Lac-St-Jean. Since most patients were found to be homozygous for a specific haplotype in this population, FAH RFLPs have permitted simple carrier detection in nine different informative HT1 families, with a confidence level of 99.9%. Heterozygosity rate values obtained from 52 carriers indicated that [approximately] 88% of families at risk from Saguenay-Lac-St-Jean are fully or partially informative. Prenatal diagnosis was also achieved in an American family. Analysis of 24 HT1 patients from nine countries gave a frequency of [approximately] 52% for haplotype 6, suggesting a relatively high association, worldwide, of HT1 with this haplotype. 31 refs., 1 fig., 3 tabs.

  2. Hungarian population data for 11 Y-STR and 49 Y-SNP markers.

    PubMed

    Völgyi, Antónia; Zalán, Andrea; Szvetnik, Eniko; Pamjav, Horolma

    2009-03-01

    49 Y-chromosomal single nucleotide polymorphisms (SNPs) with TaqMan assay and 11 Y-chromosomal STR loci were tested in 215 independent Hungarian male samples. Genetic distances to 23 other populations were calculated based on haplogroup frequencies with AMOVA implemented in Arlequin2.0. Based on distances phylogenetic tree was constructed with Neighbor-joining method using Phylip 3.66. Haplotype and haplogroup diversity values were calculated. PMID:19215861

  3. Development of an Italian RM Y-STR haplotype database: Results of the 2013 GEFI collaborative exercise.

    PubMed

    Robino, C; Ralf, A; Pasino, S; De Marchi, M R; Ballantyne, K N; Barbaro, A; Bini, C; Carnevali, E; Casarino, L; Di Gaetano, C; Fabbri, M; Ferri, G; Giardina, E; Gonzalez, A; Matullo, G; Nutini, A L; Onofri, V; Piccinini, A; Piglionica, M; Ponzano, E; Previderè, C; Resta, N; Scarnicci, F; Seidita, G; Sorçaburu-Cigliero, S; Turrina, S; Verzeletti, A; Kayser, M

    2015-03-01

    Recently introduced rapidly mutating Y-chromosomal short tandem repeat (RM Y-STR) loci, displaying a multiple-fold higher mutation rate relative to any other Y-STRs, including those conventionally used in forensic casework, have been demonstrated to improve the resolution of male lineage differentiation and to allow male relative separation usually impossible with standard Y-STRs. However, large and geographically-detailed frequency haplotype databases are required to estimate the statistical weight of RM Y-STR haplotype matches if observed in forensic casework. With this in mind, the Italian Working Group (GEFI) of the International Society for Forensic Genetics launched a collaborative exercise aimed at generating an Italian quality controlled forensic RM Y-STR haplotype database. Overall 1509 male individuals from 13 regional populations covering northern, central and southern areas of the Italian peninsula plus Sicily were collected, including both "rural" and "urban" samples classified according to population density in the sampling area. A subset of individuals was additionally genotyped for Y-STR loci included in the Yfiler and PowerPlex Y23 (PPY23) systems (75% and 62%, respectively), allowing the comparison of RM and conventional Y-STRs. Considering the whole set of 13 RM Y-STRs, 1501 unique haplotypes were observed among the 1509 sampled Italian men with a haplotype diversity of 0.999996, largely superior to Yfiler and PPY23 with 0.999914 and 0.999950, respectively. AMOVA indicated that 99.996% of the haplotype variation was within populations, confirming that genetic-geographic structure is almost undetected by RM Y-STRs. Haplotype sharing among regional Italian populations was not observed at all with the complete set of 13 RM Y-STRs. Haplotype sharing within Italian populations was very rare (0.27% non-unique haplotypes), and lower in urban (0.22%) than rural (0.29%) areas. Additionally, 422 father-son pairs were investigated, and 20.1% of them could

  4. Susceptible and protective associations of HLA DRB1*/DQB1* alleles and haplotypes with ischaemic stroke.

    PubMed

    Murali, V; Rathika, C; Ramgopal, S; Padma Malini, R; Arun Kumar, M J; Neethi Arasu, V; Jeyaram Illiayaraja, K; Balakrishnan, K

    2016-06-01

    Stroke has emerged as the second commonest cause of mortality worldwide and is a major public health problem. For the first time, we present here the association of human leucocyte antigen (HLA)-DRB1*/DQB1* alleles and haplotypes with ischaemic stroke in South Indian patients. Ischaemic stroke (IS) cases and controls were genotyped for HLA-DRB1*/DQB1* alleles by polymerase chain reaction sequence-specific primers (PCR-SSP) method. The frequencies of HLA class II alleles such as DRB1*04, DRB1*07, DRB1*11, DRB1*12, DRB1*13, DQB1*02 and DQB1*07 were high in IS patients than in the age- and gender-matched controls, suggesting that the individuals with these alleles are susceptible to ischaemic stroke in South India. The frequencies of alleles such as DRB1*03, DRB1*10, DRB1*14, DQB1*04 and DQB1*05 were less in IS cases than in the controls, suggesting a protective association. Haplotypes DRB1*04-DQB1*0301, DRB1*07-DQB1*02, DRB1*07-DQB1*0301, DRB1*11-DQB1*0301 and DRB1*13-DQB1*06 were found to be high in IS patients conferring susceptibility. The frequency of haplotype DRB1*10-DQB1*05 was high in controls conferring protection. IS-LVD and gender-stratified analysis too confirmed these susceptible and protective associations. Thus, HLA-DRB1*/DQB1* alleles and haplotypes strongly predispose South Indian population to ischaemic stroke. Further studies in different populations with large sample size or the meta-analysis are needed to explain the exact mechanism of associations of HLA gene(s) with IS. PMID:27105925

  5. A SNP Haplotype Associated with a gene resistant to Xanthomonas axonopodis pv. malvacearum in Upland Cotton (Gossyium hirsutum L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An F5 population of 285 families with each tracing back to a different F2 plant , derived from a cotton bacterial blight resistant line ‘DeltaOpal’ and a susceptible line ‘DP388’, was artificially inoculated with bacterial blight race 18 (Xanthomonas campestris pv. Malvacearum) to assay their resist...

  6. Functional promoter haplotypes of interleukin-18 condition susceptibility to severe malarial anemia and childhood mortality.

    PubMed

    Anyona, Samuel B; Kempaiah, Prakasha; Raballah, Evans; Ouma, Collins; Were, Tom; Davenport, Gregory C; Konah, Stephen N; Vulule, John M; Hittner, James B; Gichuki, Charity W; Ong'echa, John M; Perkins, Douglas J

    2011-12-01

    Severe malarial anemia (SMA) is a leading cause of morbidity and mortality in children residing in regions where Plasmodium falciparum transmission is holoendemic. Although largely unexplored in children with SMA, interleukin-18 (IL-18) is important for regulating innate and acquired immunity in inflammatory and infectious diseases. As such, we selected two functional single-nucleotide polymorphisms (SNPs) in the IL-18 promoter (-137G→C [rs187238] and -607C→A [rs1946518]) whose haplotypes encompass significant genetic variation due to the presence of strong linkage disequilibrium among these variants. The relationship between the genotypes/haplotypes, SMA (hemoglobin [Hb], <5.0 g/dl], and longitudinal clinical outcomes were then investigated in Kenyan children (n = 719). Multivariate logistic regression analyses controlling for age, gender, sickle cell trait, glucose-6-phosphate dehydrogenase (G6PD) deficiency, HIV-1, and bacteremia revealed that carriage of the -607AA genotype was associated with protection against SMA (odds ratio [OR] = 0.440 [95% confidence interval {CI} = 0.21 to 0.90], P = 0.031) in children with acute infection. In contrast, carriers of the -137G/-607C (GC) haplotype had increased susceptibility to SMA (OR = 2.050 [95% CI = 1.04 to 4.05], P = 0.039). Measurement of IL-18 gene expression in peripheral blood leukocytes demonstrated that elevated IL-18 transcripts were associated with reduced hemoglobin concentrations (ρ = -0.293, P = 0.010) and that carriers of the "susceptible" GC haplotype had elevated IL-18 transcripts (P = 0.026). Longitudinal investigation of clinical outcomes over a 3-year follow-up period revealed that carriers of the rare CC haplotype (∼1% frequency) had 5.76 times higher mortality than noncarriers (P = 0.001). Results presented here demonstrate that IL-18 promoter haplotypes that condition elevated IL-18 gene products during acute infection are associated with increased risk of SMA. Furthermore, carriage of the

  7. Integrated Genetic and Epigenetic Analysis Identifies Haplotype-Specific Methylation in the FTO Type 2 Diabetes and Obesity Susceptibility Locus

    PubMed Central

    Wilson, Gareth A.; Rakyan, Vardhman K.; Teschendorff, Andrew E.; Akan, Pelin; Stupka, Elia; Down, Thomas A.; Prokopenko, Inga; Morison, Ian M.; Mill, Jonathan; Pidsley, Ruth; Deloukas, Panos; Frayling, Timothy M.; Hattersley, Andrew T.; McCarthy, Mark I.; Beck, Stephan; Hitman, Graham A.

    2010-01-01

    Recent multi-dimensional approaches to the study of complex disease have revealed powerful insights into how genetic and epigenetic factors may underlie their aetiopathogenesis. We examined genotype-epigenotype interactions in the context of Type 2 Diabetes (T2D), focussing on known regions of genomic susceptibility. We assayed DNA methylation in 60 females, stratified according to disease susceptibility haplotype using previously identified association loci. CpG methylation was assessed using methylated DNA immunoprecipitation on a targeted array (MeDIP-chip) and absolute methylation values were estimated using a Bayesian algorithm (BATMAN). Absolute methylation levels were quantified across LD blocks, and we identified increased DNA methylation on the FTO obesity susceptibility haplotype, tagged by the rs8050136 risk allele A (p = 9.40×10−4, permutation p = 1.0×10−3). Further analysis across the 46 kb LD block using sliding windows localised the most significant difference to be within a 7.7 kb region (p = 1.13×10−7). Sequence level analysis, followed by pyrosequencing validation, revealed that the methylation difference was driven by the co-ordinated phase of CpG-creating SNPs across the risk haplotype. This 7.7 kb region of haplotype-specific methylation (HSM), encapsulates a Highly Conserved Non-Coding Element (HCNE) that has previously been validated as a long-range enhancer, supported by the histone H3K4me1 enhancer signature. This study demonstrates that integration of Genome-Wide Association (GWA) SNP and epigenomic DNA methylation data can identify potential novel genotype-epigenotype interactions within disease-associated loci, thus providing a novel route to aid unravelling common complex diseases. PMID:21124985

  8. Apolipoprotein E Variation at the Sequence Haplotype Level: Implications for the Origin and Maintenance of a Major Human Polymorphism

    PubMed Central

    Fullerton, Stephanie M.; Clark, Andrew G.; Weiss, Kenneth M.; Nickerson, Deborah A.; Taylor, Scott L.; Stengård, Jari H.; Salomaa, Veikko; Vartiainen, Erkki; Perola, Markus; Boerwinkle, Eric; Sing, Charles F.

    2000-01-01

    Three common protein isoforms of apolipoprotein E (apoE), encoded by the ε2, ε3, and ε4 alleles of the APOE gene, differ in their association with cardiovascular and Alzheimer's disease risk. To gain a better understanding of the genetic variation underlying this important polymorphism, we identified sequence haplotype variation in 5.5 kb of genomic DNA encompassing the whole of the APOE locus and adjoining flanking regions in 96 individuals from four populations: blacks from Jackson, MS (n=48 chromosomes), Mayans from Campeche, Mexico (n=48), Finns from North Karelia, Finland (n=48), and non-Hispanic whites from Rochester, MN (n=48). In the region sequenced, 23 sites varied (21 single nucleotide polymorphisms, or SNPs, 1 diallelic indel, and 1 multiallelic indel). The 22 diallelic sites defined 31 distinct haplotypes in the sample. The estimate of nucleotide diversity (site-specific heterozygosity) for the locus was 0.0005±0.0003. Sequence analysis of the chimpanzee APOE gene showed that it was most closely related to human ε4-type haplotypes, differing from the human consensus sequence at 67 synonymous (54 substitutions and 13 indels) and 9 nonsynonymous fixed positions. The evolutionary history of allelic divergence within humans was inferred from the pattern of haplotype relationships. This analysis suggests that haplotypes defining the ε3 and ε2 alleles are derived from the ancestral ε4s and that the ε3 group of haplotypes have increased in frequency, relative to ε4s, in the past 200,000 years. Substantial heterogeneity exists within all three classes of sequence haplotypes, and there are important interpopulation differences in the sequence variation underlying the protein isoforms that may be relevant to interpreting conflicting reports of phenotypic associations with variation in the common protein isoforms. PMID:10986041

  9. Annexin A5 Promoter Haplotype M2 Is Not a Risk Factor for Recurrent Pregnancy Loss in Northern Europe

    PubMed Central

    Rull, Kristiina; Christiansen, Ole B.; Nielsen, Henriette S.; Laan, Maris

    2015-01-01

    Introduction Annexin A5 is an essential component of placental integrity that may potentially mediate susceptibility to phenotypes of compromised pregnancy. A promoter haplotype termed M2 of the coding gene ANXA5 has been implicated in various pregnancy complications such as preeclampsia and recurrent pregnancy loss (RPL), however with inconclusive results. Study subjects and methods A retrospective case-control study combining resequencing and restriction fragment length polymorphism (RFLP) analysis was undertaken in 313 women with unexplained RPL and 214 fertile women from Estonia and Denmark to estimate the RPL disease risk of the M2 haplotype in Northern Europe. Comparative prevalence of the studied ANXA5 genetic variants in human populations was estimated based on the 1000 Genomes Project (n = 675, whole-genome sequencing data) and the KORA S3 500K dataset of South German samples (n = 1644, genome-wide genotyping data). Results Minor allele frequency of common polymorphisms in ANXA5 promoter was up to two-fold lower among Estonian RPL subjects than fertile controls. The M2 haplotype was not associated with RPL and a trend for decreased prevalence was observed among RPL patients compared to controls both in Estonia (8.1% vs 15.2%, respectively) and Denmark (9.7% vs 12.6%). The high M2 prevalence in fertile controls was consistent with estimations for European and East Asian populations (9.6%-16.0%). Conclusions This study cautions to consider the M2 haplotype as a deterministic factor in early pregnancy success because: i) no RPL disease risk was associated with the haplotype in two clinically well-characterized RPL case-control study samples, ii) high prevalence of the haplotype among fertile controls and world-wide populations is inconsistent with the previously proposed severe impact on early pregnancy success, iii) weak impact of M2 haplotype on the production of ANXA5 protein has been established by others. PMID:26135579

  10. eSNPO: An eQTL-based SNP Ontology and SNP functional enrichment analysis platform

    PubMed Central

    Li, Jin; Wang, Limei; Jiang, Tao; Wang, Jizhe; Li, Xue; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Lv, Hongchao; Guo, Maozu

    2016-01-01

    Genome-wide association studies (GWASs) have mined many common genetic variants associated with human complex traits like diseases. After that, the functional annotation and enrichment analysis of significant SNPs are important tasks. Classic methods are always based on physical positions of SNPs and genes. Expression quantitative trait loci (eQTLs) are genomic loci that contribute to variation in gene expression levels and have been proven efficient to connect SNPs and genes. In this work, we integrated the eQTL data and Gene Ontology (GO), constructed associations between SNPs and GO terms, then performed functional enrichment analysis. Finally, we constructed an eQTL-based SNP Ontology and SNP functional enrichment analysis platform. Taking Parkinson Disease (PD) as an example, the proposed platform and method are efficient. We believe eSNPO will be a useful resource for SNP functional annotation and enrichment analysis after we have got significant disease related SNPs. PMID:27470167

  11. eSNPO: An eQTL-based SNP Ontology and SNP functional enrichment analysis platform.

    PubMed

    Li, Jin; Wang, Limei; Jiang, Tao; Wang, Jizhe; Li, Xue; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Lv, Hongchao; Guo, Maozu

    2016-01-01

    Genome-wide association studies (GWASs) have mined many common genetic variants associated with human complex traits like diseases. After that, the functional annotation and enrichment analysis of significant SNPs are important tasks. Classic methods are always based on physical positions of SNPs and genes. Expression quantitative trait loci (eQTLs) are genomic loci that contribute to variation in gene expression levels and have been proven efficient to connect SNPs and genes. In this work, we integrated the eQTL data and Gene Ontology (GO), constructed associations between SNPs and GO terms, then performed functional enrichment analysis. Finally, we constructed an eQTL-based SNP Ontology and SNP functional enrichment analysis platform. Taking Parkinson Disease (PD) as an example, the proposed platform and method are efficient. We believe eSNPO will be a useful resource for SNP functional annotation and enrichment analysis after we have got significant disease related SNPs. PMID:27470167

  12. SNP sets and reading ability: testing confirmation of a 10-SNP set in a population sample.

    PubMed

    Luciano, Michelle; Montgomery, Grant W; Martin, Nicholas G; Wright, Margaret J; Bates, Timothy C

    2011-06-01

    A set of 10 SNPs associated with reading ability in 7-year-olds was reported based on initial pooled analyses of 100K SNP chip data, with follow-up testing stages using pooling and individual testing. Here we examine this association in an adolescent population sample of Australian twins and siblings (N = 1177) aged 12 to 25 years. One (rs1842129) of the 10 SNPs approached significance (P = .05) but no support was found for the remaining 9 SNPs or the SNP set itself. Results indicate that these SNPs are not associated with reading ability in an Australian population. The results are interpreted as supporting use of much larger SNP sets in common disorders where effects are small. PMID:21623652

  13. Bayesian quantitative trait locus mapping using inferred haplotypes.

    PubMed

    Durrant, Caroline; Mott, Richard

    2010-03-01

    We describe a fast hierarchical Bayesian method for mapping quantitative trait loci by haplotype-based association, applicable when haplotypes are not observed directly but are inferred from multiple marker genotypes. The method avoids the use of a Monte Carlo Markov chain by employing priors for which the likelihood factorizes completely. It is parameterized by a single hyperparameter, the fraction of variance explained by the quantitative trait locus, compared to the frequentist fixed-effects model, which requires a parameter for the phenotypic effect of each combination of haplotypes; nevertheless it still provides estimates of haplotype effects. We use simulation to show that the method matches the power of the frequentist regression model and, when the haplotypes are inferred, exceeds it for small QTL effect sizes. The Bayesian estimates of the haplotype effects are more accurate than the frequentist estimates, for both known and inferred haplotypes, which indicates that this advantage is independent of the effect of uncertainty in haplotype inference and will hold in comparison with frequentist methods in general. We apply the method to data from a panel of recombinant inbred lines of Arabidopsis thaliana, descended from 19 inbred founders. PMID:20048050

  14. Use of haplotypes to predict selection limits and Mendelian sampling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limits to selection and Mendelian sampling terms can be calculated using haplotypes, which are sums of individual additive effects on a chromosome. Haplotypes were imputed for 43,385 actual markers of 3,765 Jerseys using the Fortran program findhap.f90, which combines population and pedigree haploty...

  15. iXora1: exact haplotype inferencing and trait association

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: We address the task of extracting accurate haplotypes from genotype data of individuals of large F1 populations for mapping studies. While methods for inferring parental haplotype assignments on large F1 populations exist in theory, these approaches do not work in practice at high levels...

  16. Reconstruction of N-acetyltransferase 2 haplotypes using PHASE.

    PubMed

    Golka, Klaus; Blaszkewicz, Meinolf; Samimi, Mirabutaleb; Bolt, Hermann M; Selinski, Silvia

    2008-04-01

    The genotyping of N-acetyltransferase 2 (NAT2) by PCR/RFLP methods yields in a considerable percentage ambiguous results. To resolve this methodical problem a statistical approach was applied. PHASE v2.1.1, a statistical program for haplotype reconstruction was used to estimate haplotype pairs from NAT2 genotyping data, obtained by the analysis of seven single nucleotide polymorphisms relevant for Caucasians. In 1,011 out of 2,921 (35%) subjects the haplotype pairs were clearcut by the PCR/RFLP data only. For the majority of the data the applied method resulted in a multiplicity (2-4) of possible haplotype pairs. Haplotype reconstruction using PHASE v2.1.1 cleared this ambiguity in all cases but one, where an alternative haplotype pair was considered with a probability of 0.029. The estimation of the NAT2 haplotype is important because the assignment of the NAT2 alleles *12A, *12B, *12C or *13 to the rapid or slow NAT2 genotype has been discussed controversially. A clear assignment is indispensable in surveys of human bladder cancer caused by aromatic amine exposures. In conclusion, PHASE v2.1.1 software allowed an unambiguous haplotype reconstruction in 2,920 of 2,921 cases (>99.9%). PMID:17879084

  17. Restriction digestion method for haplotyping the potato psyllid, Bactericera cockerelli

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A restriction digestion method has been developed for haplotyping the potato psyllid, Bactericera cockerelli Sulc., an economically important pest of solanaceous crops. This method differentiates the four known potato psyllid haplotypes by utilizing restriction enzyme digestion of a portion of the ...

  18. Review: can diet influence the selective advantage of mitochondrial DNA haplotypes?

    PubMed

    Ballard, J William O; Youngson, Neil A

    2015-01-01

    This review explores the potential for changes in dietary macronutrients to differentially influence mitochondrial bioenergetics and thereby the frequency of mtDNA haplotypes in natural populations. Such dietary modification may be seasonal or result from biogeographic or demographic shifts. Mechanistically, mtDNA haplotypes may influence the activity of the electron transport system (ETS), retrograde signalling to the nuclear genome and affect epigenetic modifications. Thus, differential provisioning by macronutrients may lead to selection through changes in the levels of ATP production, modulation of metabolites (including AMP, reactive oxygen species (ROS) and the NAD(+)/NADH ratio) and potentially complex epigenetic effects. The exquisite complexity of dietary influence on haplotype frequency is further illustrated by the fact that macronutrients may differentially influence the selective advantage of specific mutations in different life-history stages. In Drosophila, complex I mutations may affect larval growth because dietary nutrients are fed through this complex in immaturity. In contrast, the majority of electrons are provided to complex III in adult flies. We conclude the review with a case study that considers specific interactions between diet and complex I of the ETS. Complex I is the first enzyme of the mitochondrial ETS and co-ordinates in the oxidation of NADH and transfer of electrons to ubiquinone. Although the supposition that mtDNA variants may be selected upon by dietary macronutrients could be intuitively consistent to some and counter intuitive to others, it must face a multitude of scientific hurdles before it can be recognized. PMID:26543031

  19. Review: can diet influence the selective advantage of mitochondrial DNA haplotypes?

    PubMed Central

    Ballard, J. William O.; Youngson, Neil A.

    2015-01-01

    This review explores the potential for changes in dietary macronutrients to differentially influence mitochondrial bioenergetics and thereby the frequency of mtDNA haplotypes in natural populations. Such dietary modification may be seasonal or result from biogeographic or demographic shifts. Mechanistically, mtDNA haplotypes may influence the activity of the electron transport system (ETS), retrograde signalling to the nuclear genome and affect epigenetic modifications. Thus, differential provisioning by macronutrients may lead to selection through changes in the levels of ATP production, modulation of metabolites (including AMP, reactive oxygen species (ROS) and the NAD+/NADH ratio) and potentially complex epigenetic effects. The exquisite complexity of dietary influence on haplotype frequency is further illustrated by the fact that macronutrients may differentially influence the selective advantage of specific mutations in different life-history stages. In Drosophila, complex I mutations may affect larval growth because dietary nutrients are fed through this complex in immaturity. In contrast, the majority of electrons are provided to complex III in adult flies. We conclude the review with a case study that considers specific interactions between diet and complex I of the ETS. Complex I is the first enzyme of the mitochondrial ETS and co-ordinates in the oxidation of NADH and transfer of electrons to ubiquinone. Although the supposition that mtDNA variants may be selected upon by dietary macronutrients could be intuitively consistent to some and counter intuitive to others, it must face a multitude of scientific hurdles before it can be recognized. PMID:26543031

  20. Distribution of HLA and haplotypes of Colombian and Jamaican black populations.

    PubMed

    Blank, M; Blank, A; King, S; Yashiki, S; Kuwayama, M; Fujiyama, C; Gongora, D; Zaninovic, V; Cranston, B; Hanchard, B

    1995-02-01

    To investigate the genetic background of the black populations of Colombia and Jamaica, we determined HLA types of 78 Colombian and 98 Jamaican blacks from 2 different socioeconomic groups (Jamaican #1 and Jamaican #2) and estimated the frequencies of HLA genes and haplotypes. A phylogenetic tree based on the HLA gene frequencies revealed that Jamaican #1 and Jamaican #2 were distinct from each other, Jamaican #1 being closely related to the Colombian blacks and the Jamaican #2 being closely related to Senegalese and Zairean populations. Three-locus HLA haplotypes of Colombian and Jamaican #1 blacks were an admixture between Africans and Caucasians or South American Indians, while Jamaican #2 blacks were relatively homogeneous and appeared to conserve African lineages. The major five-locus HLA haplotypes were not shared among Colombian, Jamaican #1 and Jamaican #2 blacks. These results indicated that the black populations of Colombia and Jamaican were originated from African blacks and admixed variably with Caucasians and South American Indians to make genetic subpopulations in Colombia and Jamaica. PMID:7792756

  1. An integrative segmentation method for detecting germline copy number variations in SNP arrays.

    PubMed

    Shi, Jianxin; Li, Peng

    2012-05-01

    Germline copy number variations (CNVs) are a major source of genetic variation in humans. In large-scale studies of complex diseases, CNVs are usually detected from data generated by single nucleotide polymorphism (SNP) genotyping arrays. In this paper, we develop an integrative segmentation method, SegCNV, for detecting CNVs integrating both log R ratio (LRR) and B allele frequency (BAF). Based on simulation studies, SegCNV had modestly better power to detect deletions and substantially better power to detect duplications compared with circular binary segmentation (CBS) that relies purely on LRRs; and it had better power to detect deletions and a comparable performance to detect duplications compared with PennCNV and QuantiSNP. In two Hapmap subjects with deep sequence data available as a gold standard, SegCNV detected more true short deletions than PennCNV and QuantiSNP. For 21 short duplications validated experimentally in the AGRE dataset, SegCNV, QuantiSNP, and PennCNV detected all of them while CBS detected only three. SegCNV is much faster than the HMM-based (where HMM is hidden Markov model) methods, taking only several seconds to analyze genome-wide data for one subject. PMID:22539397

  2. Y-chromosome polymorphisms and ethnic group – a combined STR and SNP approach in a population sample from northern Italy

    PubMed Central

    Cortellini, Venusia; Verzeletti, Andrea; Cerri, Nicoletta; Marino, Alberto; De Ferrari, Francesco

    2013-01-01

    Aim To find an association between Y chromosome polymorphisms and some ethnic groups. Methods Short tandem repeats (STR) and single-nucleotide polymorphisms (SNP) on the Y chromosome were typed in 311 unrelated men from four different ethnic groups – Italians from northern Italy, Albanians, Africans from the Maghreb region, and Indo-Pakistanis, using the AmpFlSTR® Yfiler PCR Amplification Kit and the SNaPshot Multiplex Kit. Results STRs analysis found 299 different haplotypes and SNPs analysis 11 different haplogroups. Haplotypes and haplogroups were analyzed and compared between different ethnic groups. Significant differences were found among all the population groups, except between Italians and Indo-Pakistanis and between Albanians and Indo-Pakistanis. Conclusions Typing both STRs and SNPs on the Y chromosome could become useful in determining ethnic origin of a potential suspect. PMID:23771759

  3. HLA haplotypes and TNF polymorphism do not associate with longevity in the Irish.

    PubMed

    Ross, Owen A; Curran, Martin D; Rea, I Maeve; Hyland, Paul; Duggan, Orla; Barnett, Christopher R; Annett, Kathryn; Patterson, Chris; Barnett, Yvonne A; Middleton, Derek

    2003-04-01

    Polymorphism of the human leukocyte antigen has been implicated in a number of autoimmune disorders including ageing. In the course of the present study, no association of the human leukocyte antigen (HLA)-A1, B8, DR3 haplotype with a male Irish aged population, as previously reported, was observed. Two polymorphic nucleotides in the TNF cluster (G-308A TNF-alpha and G+252A TNF-beta), associated with increased TNF-alpha production, were shown to be in tight linkage disequilibrium with the class I and II HLA loci, generating HLA haplotypes with extended linkage disequilibrium. However, no age-related allele or genotype frequencies were observed for either polymorphic nucleotide. PMID:12714268

  4. Predominance of B haplotype associated KIR genes in Tamil Speaking Dravidians.

    PubMed

    Maruthamuthu, Stalinraja; Mariakuttikan, Jayalakshmi

    2015-05-01

    Killer cell immunoglobulin like receptors (KIRs) are a group of activating (aKIRs) and inhibitory receptors (iKIRs) expressed on subsets of lymphoid cells. Their interaction with HLA class I molecules modulate the innate and adaptive immune response against infections and malignancies. KIR haplotypes varies in gene content and also at allelic level, thereby, distinguishing individuals and populations. Hence, the present study is aimed to determine the KIR gene diversity in Piramalai Kallar (PK) population of South India. The PK population shows diverged KIR gene frequencies and novel haplotypes than other South Indian populations. 52 different KIR gene profiles were identified and 18 of them were new in this population. In phylogenetic analysis the study population is positioned between African and Iranian population in the clade, which supports the South African ancestry of Indian population. PMID:25842054

  5. Mathematical properties and bounds on haplotyping populations by pure parsimony.

    PubMed

    Wang, I-Lin; Chang, Chia-Yuan

    2011-06-01

    Although the haplotype data can be used to analyze the function of DNA, due to the significant efforts required in collecting the haplotype data, usually the genotype data is collected and then the population haplotype inference (PHI) problem is solved to infer haplotype data from genotype data for a population. This paper investigates the PHI problem based on the pure parsimony criterion (HIPP), which seeks the minimum number of distinct haplotypes to infer a given genotype data. We analyze the mathematical structure and properties for the HIPP problem, propose techniques to reduce the given genotype data into an equivalent one of much smaller size, and analyze the relations of genotype data using a compatible graph. Based on the mathematical properties in the compatible graph, we propose a maximal clique heuristic to obtain an upper bound, and a new polynomial-sized integer linear programming formulation to obtain a lower bound for the HIPP problem. PMID:21354185

  6. Haplotype map of sickle cell anemia in Tunisia.

    PubMed

    Moumni, Imen; Ben Mustapha, Maha; Sassi, Sarra; Zorai, Amine; Ben Mansour, Ikbel; Douzi, Kais; Chouachi, Dorra; Mellouli, Fethi; Bejaoui, Mohamed; Abbes, Salem

    2014-01-01

    β-Globin haplotypes are important to establish the ethnic origin and predict the clinical development of sickle cell disease patients (SCD). To determine the chromosomal background of β (S) Tunisian sickle cell patients, in this first study in Tunisia, we have explored four polymorphic regions of β-globin cluster on chromosome 11. It is the 5' region of β-LCR-HS2 site, the intervening sequence II (IVSII) region of two fetal ((G)γ and (A)γ) genes and the 5' region of β-globin gene. The results reveal a high molecular diversity of a microsatellite configuration describing the sequences haplotypes. The linkage disequilibrium analysis showed various haplotype combinations giving 22 "extended haplotypes". These results confirm the utility of the β-globin haplotypes for population studies and contribute to knowledge of the Tunisian gene pool, as well as establishing the role of genetic markers in physiopathology of SCD. PMID:25197158

  7. Chromosomal Haplotypes by Genetic Phasing of Human Families

    PubMed Central

    Roach, Jared C.; Glusman, Gustavo; Hubley, Robert; Montsaroff, Stephen Z.; Holloway, Alisha K.; Mauldin, Denise E.; Srivastava, Deepak; Garg, Vidu; Pollard, Katherine S.; Galas, David J.; Hood, Leroy; Smit, Arian F.A.

    2011-01-01

    Assignment of alleles to haplotypes for nearly all the variants on all chromosomes can be performed by genetic analysis of a nuclear family with three or more children. Whole-genome sequence data enable deterministic phasing of nearly all sequenced alleles by permitting assignment of recombinations to precise chromosomal positions and specific meioses. We demonstrate this process of genetic phasing on two families each with four children. We generate haplotypes for all of the children and their parents; these haplotypes span all genotyped positions, including rare variants. Misassignments of phase between variants (switch errors) are nearly absent. Our algorithm can also produce multimegabase haplotypes for nuclear families with just two children and can handle families with missing individuals. We implement our algorithm in a suite of software scripts (Haploscribe). Haplotypes and family genome sequences will become increasingly important for personalized medicine and for fundamental biology. PMID:21855840

  8. Smarter clustering methods for SNP genotype calling

    PubMed Central

    Lin, Yan; Tseng, George C.; Cheong, Soo Yeon; Bean, Lora J. H.; Sherman, Stephanie L.; Feingold, Eleanor

    2008-01-01

    Motivation: Most genotyping technologies for single nucleotide polymorphism (SNP) markers use standard clustering methods to ‘call’ the SNP genotypes. These methods are not always optimal in distinguishing the genotype clusters of a SNP because they do not take advantage of specific features of the genotype calling problem. In particular, when family data are available, pedigree information is ignored. Furthermore, prior information about the distribution of the measurements for each cluster can be used to choose an appropriate model-based clustering method and can significantly improve the genotype calls. One special genotyping problem that has never been discussed in the literature is that of genotyping of trisomic individuals, such as individuals with Down syndrome. Calling trisomic genotypes is a more complicated problem, and the addition of external information becomes very important. Results: In this article, we discuss the impact of incorporating external information into clustering algorithms to call the genotypes for both disomic and trisomic data. We also propose two new methods to call genotypes using family data. One is a modification of the K-means method and uses the pedigree information by updating all members of a family together. The other is a likelihood-based method that combines the Gaussian or beta-mixture model with pedigree information. We compare the performance of these two methods and some other existing methods using simulation studies. We also compare the performance of these methods on a real dataset generated by the Illumina platform (www.illumina.com). Availability: The R code for the family-based genotype calling methods (SNPCaller) is available to be downloaded from the following website: http://watson.hgen.pitt.edu/register. Contact: liny@upmc.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:18826959

  9. A haplotype map of the human genome

    PubMed Central

    2007-01-01

    Inherited genetic variation has a critical but as yet largely uncharacterized role in human disease. Here we report a public database of common variation in the human genome: more than one million single nucleotide polymorphisms (SNPs) for which accurate and complete genotypes have been obtained in 269 DNA samples from four populations, including ten 500-kilobase regions in which essentially all information about common DNA variation has been extracted. These data document the generality of recombination hotspots, a block-like structure of linkage disequilibrium and low haplotype diversity, leading to substantial correlations of SNPs with many of their neighbours. We show how the HapMap resource can guide the design and analysis of genetic association studies, shed light on structural variation and recombination, and identify loci that may have been subject to natural selection during human evolution. PMID:16255080

  10. The Holstein Friesian Lethal Haplotype 5 (HH5) Results from a Complete Deletion of TBF1M and Cholesterol Deficiency (CDH) from an ERV-(LTR) Insertion into the Coding Region of APOB

    PubMed Central

    Schütz, Ekkehard; Wehrhahn, Christin; Wanjek, Marius; Bortfeld, Ralf; Wemheuer, Wilhelm E.; Beck, Julia; Brenig, Bertram

    2016-01-01

    Background With the availability of massive SNP data for several economically important cattle breeds, haplotype tests have been performed to identify unknown recessive disorders. A number of so-called lethal haplotypes, have been uncovered in Holstein Friesian cattle and, for at least seven of these, the causative mutations have been identified in candidate genes. However, several lethal haplotypes still remain elusive. Here we report the molecular genetic causes of lethal haplotype 5 (HH5) and cholesterol deficiency (CDH). A targeted enrichment for the known genomic regions, followed by massive parallel sequencing was used to interrogate for causative mutations in a case/control approach. Methods Targeted enrichment for the known genomic regions, followed by massive parallel sequencing was used in a case/control approach. PCRs for the causing mutations were developed and compared to routine imputing in 2,100 (HH5) and 3,100 (CDH) cattle. Results HH5 is caused by a deletion of 138kbp, spanning position 93,233kb to 93,371kb on chromosome 9 (BTA9), harboring only dimethyl-adenosine transferase 1 (TFB1M). The deletion breakpoints are flanked by bovine long interspersed nuclear elements Bov-B (upstream) and L1ME3 (downstream), suggesting a homologous recombination/deletion event. TFB1M di-methylates adenine residues in the hairpin loop at the 3’-end of mitochondrial 12S rRNA, being essential for synthesis and function of the small ribosomal subunit of mitochondria. Homozygous TFB1M-/- mice reportedly exhibit embryonal lethality with developmental defects. A 2.8% allelic frequency was determined for the German HF population. CDH results from a 1.3kbp insertion of an endogenous retrovirus (ERV2-1-LTR_BT) into exon 5 of the APOB gene at BTA11:77,959kb. The insertion is flanked by 6bp target site duplications as described for insertions mediated by retroviral integrases. A premature stop codon in the open reading frame of APOB is generated, resulting in a truncation of

  11. Linkage mapping bovine EST-based SNP

    PubMed Central

    Snelling, Warren M; Casas, Eduardo; Stone, Roger T; Keele, John W; Harhay, Gregory P; Bennett, Gary L; Smith, Timothy PL

    2005-01-01

    Background Existing linkage maps of the bovine genome primarily contain anonymous microsatellite markers. These maps have proved valuable for mapping quantitative trait loci (QTL) to broad regions of the genome, but more closely spaced markers are needed to fine-map QTL, and markers associated with genes and annotated sequence are needed to identify genes and sequence variation that may explain QTL. Results Bovine expressed sequence tag (EST) and bacterial artificial chromosome (BAC)sequence data were used to develop 918 single nucleotide polymorphism (SNP) markers to map genes on the bovine linkage map. DNA of sires from the MARC reference population was used to detect SNPs, and progeny and mates of heterozygous sires were genotyped. Chromosome assignments for 861 SNPs were determined by twopoint analysis, and positions for 735 SNPs were established by multipoint analyses. Linkage maps of bovine autosomes with these SNPs represent 4585 markers in 2475 positions spanning 3058 cM . Markers include 3612 microsatellites, 913 SNPs and 60 other markers. Mean separation between marker positions is 1.2 cM. New SNP markers appear in 511 positions, with mean separation of 4.7 cM. Multi-allelic markers, mostly microsatellites, had a mean (maximum) of 216 (366) informative meioses, and a mean 3-lod confidence interval of 3.6 cM Bi-allelic markers, including SNP and other marker types, had a mean (maximum) of 55 (191) informative meioses, and were placed within a mean 8.5 cM 3-lod confidence interval. Homologous human sequences were identified for 1159 markers, including 582 newly developed and mapped SNP. Conclusion Addition of these EST- and BAC-based SNPs to the bovine linkage map not only increases marker density, but provides connections to gene-rich physical maps, including annotated human sequence. The map provides a resource for fine-mapping quantitative trait loci and identification of positional candidate genes, and can be integrated with other data to guide and

  12. Y chromosome haplotype diversity of domestic sheep (Ovis aries) in northern Eurasia.

    PubMed

    Zhang, Min; Peng, Wei-Feng; Yang, Guang-Li; Lv, Feng-Hua; Liu, Ming-Jun; Li, Wen-Rong; Liu, Yong-Gang; Li, Jin-Quan; Wang, Feng; Shen, Zhi-Qiang; Zhao, Sheng-Guo; Hehua, Eer; Marzanov, Nurbiy; Murawski, Maziek; Kantanen, Juha; Li, Meng-Hua

    2014-12-01

    Variation in two SNPs and one microsatellite on the Y chromosome was analyzed in a total of 663 rams representing 59 breeds from a large geographic range in northern Eurasia. SNPA-oY1 showed the highest allele frequency (91.55%) across the breeds, whereas SNPG-oY1 was present in only 56 samples. Combined genotypes established seven haplotypes (H4, H5, H6, H7, H8, H12 and H19). H6 dominated in northern Eurasia, and H8 showed the second-highest frequency. H4, which had been earlier reported to be absent in European breeds, was detected in one European breed (Swiniarka), whereas H7, which had been previously identified to be unique to European breeds, was present in two Chinese breeds (Ninglang Black and Large-tailed Han), one Buryatian (Transbaikal Finewool) and two Russian breeds (North Caucasus Mutton-Wool and Kuibyshev). H12, which had been detected only in Turkish breeds, was also found in Chinese breeds in this work. An overall low level of haplotype diversity (median h = 0.1288) was observed across the breeds with relatively higher median values in breeds from the regions neighboring the Near Eastern domestication center of sheep. H6 is the dominant haplotype in northwestern and eastern China, in which the haplotype distribution could be explained by the historical translocations of the H4 and H8 Y chromosomes to China via the Mongol invasions followed by expansions to northwestern and eastern China. Our findings extend previous results of sheep Y chromosomal genetic variability and indicate probably recent paternal gene flows between sheep breeds from distinct major geographic regions. PMID:25204383

  13. Identity of the mtDNA haplotype(s) of Phytophthora infestans in historical specimens from the Irish potato famine.

    PubMed

    May, Kimberley Jane; Ristaino, Jean Beagle

    2004-05-01

    The mtDNA haplotypes of the plant pathogen Phytophthora infestans present in dried potato and tomato leaves from herbarium specimens collected during the Irish potato famine and later in the 19th and early 20th century were identified. A 100 bp fragment of ribosomal DNA (rDNA) specific for P. infestans was amplified from 90% of the specimens (n = 186), confirming infection by P. infestans. Primers were designed that distinguish the extant mtDNA haplotypes. 86% percent of the herbarium specimens from historic epidemics were infected with the Ia mtDNA haplotype. Two mid-20th century potato leaves from Ecuador (1967) and Bolivia (1944) were infected with the Ib mtDNA haplotype of the pathogen. Both the Ia and IIb haplotypes were found in specimens collected in Nicaragua in the 1950s. The data suggest that the Ia haplotype of P. infestans was responsible for the historic epidemics during the 19th century in the UK, Europe, and the USA. The Ib mtDNA haplotype of the pathogen was dispersed later in the early 20th century from Bolivia and Ecuador. Multiple haplotypes were present outside Mexico in the 1940s-60s, indicating that pathogen diversity was greater than previously believed. PMID:15229999

  14. pfSNP: An integrated potentially functional SNP resource that facilitates hypotheses generation through knowledge syntheses.

    PubMed

    Wang, Jingbo; Ronaghi, Mostafa; Chong, Samuel S; Lee, Caroline G L

    2011-01-01

    Currently, >14,000,000 single nucleotide polymorphisms (SNPs) are reported. Identifying phenotype-affecting SNPs among these many SNPs pose significant challenges. Although several Web resources are available that can inform about the functionality of SNPs, these resources are mainly annotation databases and are not very comprehensive. In this article, we present a comprehensive, well-annotated, integrated pfSNP (potentially functional SNPs) Web resource (http://pfs.nus.edu.sg/), which is aimed to facilitate better hypothesis generation through knowledge syntheses mediated by better data integration and a user-friendly Web interface. pfSNP integrates >40 different algorithms/resources to interrogate >14,000,000 SNPs from the dbSNP database for SNPs of potential functional significance based on previous published reports, inferred potential functionality from genetic approaches as well as predicted potential functionality from sequence motifs. Its query interface has the user-friendly "auto-complete, prompt-as-you-type" feature and is highly customizable, facilitating different combination of queries using Boolean-logic. Additionally, to facilitate better understanding of the results and aid in hypotheses generation, gene/pathway-level information with text clouds highlighting enriched tissues/pathways as well as detailed-related information are also provided on the results page. Hence, the pfSNP resource will be of great interest to scientists focusing on association studies as well as those interested to experimentally address the functionality of SNPs. PMID:20672376

  15. KinSNP software for homozygosity mapping of disease genes using SNP microarrays.

    PubMed

    Amir, El-Ad David; Bartal, Ofer; Morad, Efrat; Nagar, Tal; Sheynin, Jony; Parvari, Ruti; Chalifa-Caspi, Vered

    2010-08-01

    Consanguineous families affected with a recessive genetic disease caused by homozygotisation of a mutation offer a unique advantage for positional cloning of rare diseases. Homozygosity mapping of patient genotypes is a powerful technique for the identification of the genomic locus harbouring the causing mutation. This strategy relies on the observation that in these patients a large region spanning the disease locus is also homozygous with high probability. The high marker density in single nucleotide polymorphism (SNP) arrays is extremely advantageous for homozygosity mapping. We present KinSNP, a user-friendly software tool for homozygosity mapping using SNP arrays. The software searches for stretches of SNPs which are homozygous to the same allele in all ascertained sick individuals. User-specified parameters control the number of allowed genotyping 'errors' within homozygous blocks. Candidate disease regions are then reported in a detailed, coloured Excel file, along with genotypes of family members and healthy controls. An interactive genome browser has been included which shows homozygous blocks, individual genotypes, genes and further annotations along the chromosomes, with zooming and scrolling capabilities. The software has been used to identify the location of a mutated gene causing insensitivity to pain in a large Bedouin family. KinSNP is freely available from. PMID:20846928

  16. Genetic Characterization and Linkage Disequilibrium Estimation of a Global Maize Collection Using SNP Markers

    PubMed Central

    Yan, Jianbing; Shah, Trushar; Warburton, Marilyn L.; Buckler, Edward S.; McMullen, Michael D.; Crouch, Jonathan

    2009-01-01

    A newly developed maize Illumina GoldenGate Assay with 1536 SNPs from 582 loci was used to genotype a highly diverse global maize collection of 632 inbred lines from temperate, tropical, and subtropical public breeding programs. A total of 1229 informative SNPs and 1749 haplotypes within 327 loci was used to estimate the genetic diversity, population structure, and familial relatedness. Population structure identified tropical and temperate subgroups, and complex familial relationships were identified within the global collection. Linkage disequilibrium (LD) was measured overall and within chromosomes, allelic frequency groups, subgroups related by geographic origin, and subgroups of different sample sizes. The LD decay distance differed among chromosomes and ranged between 1 to 10 kb. The LD distance increased with the increase of minor allelic frequency (MAF), and with smaller sample sizes, encouraging caution when using too few lines in a study. The LD decay distance was much higher in temperate than in tropical and subtropical lines, because tropical and subtropical lines are more diverse and contain more rare alleles than temperate lines. A core set of inbreds was defined based on haplotypes, and 60 lines capture 90% of the haplotype diversity of the entire panel. The defined core sets and the entire collection can be used widely for different research targets. PMID:20041112

  17. SNP marker detection and genotyping in tilapia.

    PubMed

    Van Bers, N E M; Crooijmans, R P M A; Groenen, M A M; Dibbits, B W; Komen, J

    2012-09-01

    We have generated a unique resource consisting of nearly 175 000 short contig sequences and 3569 SNP markers from the widely cultured GIFT (Genetically Improved Farmed Tilapia) strain of Nile tilapia (Oreochromis niloticus). In total, 384 SNPs were selected to monitor the wider applicability of the SNPs by genotyping tilapia individuals from different strains and different geographical locations. In all strains and species tested (O. niloticus, O. aureus and O. mossambicus), the genotyping assay was working for a similar number of SNPs (288-305 SNPs). The actual number of polymorphic SNPs was, as expected, highest for individuals from the GIFT population (255 SNPs). In the individuals from an Egyptian strain and in individuals caught in the wild in the basin of the river Volta, 197 and 163 SNPs were polymorphic, respectively. A pairwise calculation of Nei's genetic distance allowed the discrimination of the individual strains and species based on the genotypes determined with the SNP set. We expect that this set will be widely applicable for use in tilapia aquaculture, e.g. for pedigree reconstruction. In addition, this set is currently used for assaying the genetic diversity of native Nile tilapia in areas where tilapia is, or will be, introduced in aquaculture projects. This allows the tracing of escapees from aquaculture and the monitoring of effects of introgression and hybridization. PMID:22524158

  18. SNP Discovery in the Transcriptome of White Pacific Shrimp Litopenaeus vannamei by Next Generation Sequencing

    PubMed Central

    Yu, Yang; Wei, Jiankai; Zhang, Xiaojun; Liu, Jingwen; Liu, Chengzhang; Li, Fuhua; Xiang, Jianhai

    2014-01-01

    The application of next generation sequencing technology has greatly facilitated high throughput single nucleotide polymorphism (SNP) discovery and genotyping in genetic research. In the present study, SNPs were discovered based on two transcriptomes of Litopenaeus vannamei (L. vannamei) generated from Illumina sequencing platform HiSeq 2000. One transcriptome of L. vannamei was obtained through sequencing on the RNA from larvae at mysis stage and its reference sequence was de novo assembled. The data from another transcriptome were downloaded from NCBI and the reads of the two transcriptomes were mapped separately to the assembled reference by BWA. SNP calling was performed using SAMtools. A total of 58,717 and 36,277 SNPs with high quality were predicted from the two transcriptomes, respectively. SNP calling was also performed using the reads of two transcriptomes together, and a total of 96,040 SNPs with high quality were predicted. Among these 96,040 SNPs, 5,242 and 29,129 were predicted as non-synonymous and synonymous SNPs respectively. Characterization analysis of the predicted SNPs in L. vannamei showed that the estimated SNP frequency was 0.21% (one SNP per 476 bp) and the estimated ratio for transition to transversion was 2.0. Fifty SNPs were randomly selected for validation by Sanger sequencing after PCR amplification and 76% of SNPs were confirmed, which indicated that the SNPs predicted in this study were reliable. These SNPs will be very useful for genetic study in L. vannamei, especially for the high density linkage map construction and genome-wide association studies. PMID:24498047

  19. Development and Characterization of a High Density SNP Genotyping Assay for Cattle

    PubMed Central

    Matukumalli, Lakshmi K.; Lawley, Cynthia T.; Schnabel, Robert D.; Taylor, Jeremy F.; Allan, Mark F.; Heaton, Michael P.; O'Connell, Jeff; Moore, Stephen S.; Smith, Timothy P. L.; Sonstegard, Tad S.; Van Tassell, Curtis P.

    2009-01-01

    The success of genome-wide association (GWA) studies for the detection of sequence variation affecting complex traits in human has spurred interest in the use of large-scale high-density single nucleotide polymorphism (SNP) genotyping for the identification of quantitative trait loci (QTL) and for marker-assisted selection in model and agricultural species. A cost-effective and efficient approach for the development of a custom genotyping assay interrogating 54,001 SNP loci to support GWA applications in cattle is described. A novel algorithm for achieving a compressed inter-marker interval distribution proved remarkably successful, with median interval of 37 kb and maximum predicted gap of <350 kb. The assay was tested on a panel of 576 animals from 21 cattle breeds and six outgroup species and revealed that from 39,765 to 46,492 SNP are polymorphic within individual breeds (average minor allele frequency (MAF) ranging from 0.24 to 0.27). The assay also identified 79 putative copy number variants in cattle. Utility for GWA was demonstrated by localizing known variation for coat color and the presence/absence of horns to their correct genomic locations. The combination of SNP selection and the novel spacing algorithm allows an efficient approach for the development of high-density genotyping platforms in species having full or even moderate quality draft sequence. Aspects of the approach can be exploited in species which lack an available genome sequence. The BovineSNP50 assay described here is commercially available from Illumina and provides a robust platform for mapping disease genes and QTL in cattle. PMID:19390634

  20. Human dopamine transporter gene: differential regulation of 18-kb haplotypes

    PubMed Central

    Zhao, Ying; Xiong, Nian; Liu, Yang; Zhou, Yanhong; Li, Nuomin; Qing, Hong; Lin, Zhicheng

    2013-01-01

    Aim Since previous functional studies of short haplotypes and polymorphic sites of SLC6A3 have shown variant-dependent and drug-sensitive promoter activity, this study aimed to understand whether a large SLC6A3 regulatory region, containing these small haplotypes and polymorphic sites, can display haplotype-dependent promoter activity in a drug-sensitive and pathway-related manner. Materials & methods By creating and using a single copy number luciferase-reporter vector, we examined regulation of two different SLC6A3 haplotypes (A and B) of the 5′ 18-kb promoter and two known downstream regulatory variable number tandem repeats by 17 drugs in four different cellular models. Results The two regulatory haplotypes displayed up to 3.2-fold difference in promoter activity. The regulations were drug selective (37.5% of the drugs showed effects), and both haplotype and cell type dependent. Pathway analysis revealed at least 13 main signaling hubs targeting SLC6A3, including histone deacetylation, AKT, PKC and CK2 α-chains. Conclusion SLC6A3 may be regulated via either its promoter or the variable number tandem repeats independently by specific signaling pathways and in a haplotype-dependent manner. Furthermore, we have developed the first pathway map for SLC6A3 regulation. These findings provide a framework for understanding complex and variant-dependent regulations of SLC6A3. PMID:24024899

  1. A spatial haplotype copying model with applications to genotype imputation.

    PubMed

    Yang, Wen-Yun; Hormozdiari, Farhad; Eskin, Eleazar; Pasaniuc, Bogdan

    2015-05-01

    Ever since its introduction, the haplotype copy model has proven to be one of the most successful approaches for modeling genetic variation in human populations, with applications ranging from ancestry inference to genotype phasing and imputation. Motivated by coalescent theory, this approach assumes that any chromosome (haplotype) can be modeled as a mosaic of segments copied from a set of chromosomes sampled from the same population. At the core of the model is the assumption that any chromosome from the sample is equally likely to contribute a priori to the copying process. Motivated by recent works that model genetic variation in a geographic continuum, we propose a new spatial-aware haplotype copy model that jointly models geography and the haplotype copying process. We extend hidden Markov models of haplotype diversity such that at any given location, haplotypes that are closest in the genetic-geographic continuum map are a priori more likely to contribute to the copying process than distant ones. Through simulations starting from the 1000 Genomes data, we show that our model achieves superior accuracy in genotype imputation over the standard spatial-unaware haplotype copy model. In addition, we show the utility of our model in selecting a small personalized reference panel for imputation that leads to both improved accuracy as well as to a lower computational runtime than the standard approach. Finally, we show our proposed model can be used to localize individuals on the genetic-geographical map on the basis of their genotype data. PMID:25526526

  2. A Potential Relationship among Beta-Defensins Haplotype, SOX7 Duplication and Cardiac Defects

    PubMed Central

    Fang, Shaohai; Xu, Yuejuan; Sun, Kun; Chen, Sun; Xu, Rang

    2013-01-01

    Objective To determine the pathogenesis of a patient born with congenital heart defects, who had appeared normal in prenatal screening. Methods In routine prenatal screening, G-banding was performed to analyse the karyotypes of the family and fluorescence in situ hybridization was used to investigate the 22q11.2 deletion in the fetus. After birth, the child was found to be suffering from heart defects by transthoracic echocardiography. In the following study, sequencing was used to search for potential mutations in pivotal genes. SNP-array was employed for fine mapping of the aberrant region and quantitative real-time PCR was used to confirm the results. Furthermore, other patients with a similar phenotype were screened for the same genetic variations. To compare with a control, these variations were also assessed in the general population. Results The child and his mother each had a region that was deleted in the beta-defensin repeats, which are usually duplicated in the general population. Besides, the child carried a SOX7-gene duplication. While this duplication was not detected in his mother, it was found in two other patients with cardiac defects who also had the similar deletion in the beta-defensin repeats. Conclusion The congenital heart defects of the child were probably caused by a SOX7-gene duplication, which may be a consequence of the partial haplotype of beta-defensin regions at 8p23.1. To our knowledge, this is the first congenital heart defect case found to have the haplotype of beta-defensin and the duplication of SOX7. PMID:24009689

  3. Identification of rheumatoid arthritis biomarkers based on single nucleotide polymorphisms and haplotype blocks: A systematic review and meta-analysis

    PubMed Central

    Saad, Mohamed N.; Mabrouk, Mai S.; Eldeib, Ayman M.; Shaker, Olfat G.

    2015-01-01

    Genetics of autoimmune diseases represent a growing domain with surpassing biomarker results with rapid progress. The exact cause of Rheumatoid Arthritis (RA) is unknown, but it is thought to have both a genetic and an environmental bases. Genetic biomarkers are capable of changing the supervision of RA by allowing not only the detection of susceptible individuals, but also early diagnosis, evaluation of disease severity, selection of therapy, and monitoring of response to therapy. This review is concerned with not only the genetic biomarkers of RA but also the methods of identifying them. Many of the identified genetic biomarkers of RA were identified in populations of European and Asian ancestries. The study of additional human populations may yield novel results. Most of the researchers in the field of identifying RA biomarkers use single nucleotide polymorphism (SNP) approaches to express the significance of their results. Although, haplotype block methods are expected to play a complementary role in the future of that field. PMID:26843965

  4. HLA-G UTR haplotype conservation in the Malian population: association with soluble HLA-G.

    PubMed

    Carlini, Federico; Traore, Karim; Cherouat, Nissem; Roubertoux, Pierre; Buhler, Stéphane; Cortey, Martì; Simon, Sophie; Doumbo, Ogobara; Chiaroni, Jacques; Picard, Christophe; Di Cristofaro, Julie

    2013-01-01

    The HLA-G molecule plays an important role in immunomodulation. In a previous study carried out on a southern French population our team showed that HLA-G haplotypes, defined by SNPs in the coding region and specific SNPs located in 5'URR and 3'UTR regulatory regions, are associated with differential soluble HLA-G expression (sHLA-G). Furthermore, the structure of these HLA-G haplotypes appears to be conserved in geographically distant populations. The aim of our study is to confirm these expectations in a sub-Saharan African population and to explore additional factors, such as HLA-A alleles, that might influence sHLA-G expression. DNA and plasma samples were collected from 229 Malians; HLA-G and HLA-A genotyping were respectively performed by the Snap Shot® method and by Luminex™ technology. sHLA-G dosage was performed using an ELISA kit. HLA-G and HLA-A allelic and haplotypic frequencies were estimated using an EM algorithm from the Gene[Rate] program. Associations between genetic and non genetic parameters with sHLA-G were performed using a non-parametric test with GRAPH PAD Prism 5. Our results reveal a good conservation of the HLA-G UTR haplotype structure in populations with different origins and demographic histories. These UTR haplotypes appear to be involved in different sHLA-G expression patterns. Specifically, the UTR-2 haplotype was associated with low sHLA-G levels, displaying a dominant negative effect. Furthermore, an allelic effect of both HLA-G and HLA-A, as well as non genetic parameters, such as age and gender possibly linked to osteogenesis and sexual hormones, also seem to be involved in the modulation of sHLA-G. These data suggest that further investigation in larger cohorts and in populations from various ethnical backgrounds is necessary not only to detect new functional polymorphism in HLA-G regulatory regions, but also to reveal the extent of biological phenomena that influence sHLA-G secretion and this might therefore have an impact

  5. "Extended" A1, B8, DR3 haplotype shows remarkable linkage disequilibrium but is similar to nonextended haplotypes in terms of diabetes risk.

    PubMed

    Ide, Akane; Babu, Sunanda R; Robles, David T; Wang, Tianbao; Erlich, Henry A; Bugawan, Teodorica L; Rewers, Marian; Fain, Pamela R; Eisenbarth, George S

    2005-06-01

    To evaluate potential differential diabetes risk of DR3 haplotypes we have evaluated class I alleles as well as two microsatellites previously associated with differential risk associated with DR3 haplotypes. We found that over one-third of patient DR3 chromosomes consisted of an extended DR3 haplotype, from DQ2 to D6S2223 (DQ2, DR3, D6S273-143, MIC-A5.1, HLA-B8, HLA-Cw7, HLA-A1, and D6S2223-177) with an identical extended haplotype in controls. The extended haplotype was present more frequently (35.1% of autoimmune-associated DR3 haplotypes, 39.4% of control DR3 haplotypes) than other haplotypes (no other haplotype >5% of DR3 haplotypes) and remarkably conserved, but it was not transmitted from parents to affected children more frequently than nonconserved DR3-bearing haplotypes. This suggests that if all alleles are truly identical for the major A1, B8, DR3 haplotype (between A1 and DR3), with different alleles on nonconserved haplotypes without differential diabetes risk, then in this region of the genome DR3-DQ2 may be the primary polymorphisms of common haplotypes contributing to diabetes risk. PMID:15919812

  6. Mitochondrial genome haplotype hypervariation within the isopod parasitic nematode Thaumamermis cosgrovei.

    PubMed

    Tang, Sha; Hyman, Bradley C

    2007-06-01

    Characterization of mitochondrial genomes from individual Thaumamermis cosgrovei nematodes, obligate parasites of the isopod Armadillidium vulgare, revealed that numerous mtDNA haplotypes, ranging in size from 19 to 34 kb, are maintained in several spatially separated isopod populations. The magnitude and frequency of conspecific mtDNA size variation is unprecedented among all studied size-polymorphic metazoan mitochondrial genomes. To understand the molecular basis of this hypervariation, complete nucleotide sequences of two T. cosgrovei mtDNA haplotypes were determined. A hypervariable segment, residing between the atp6 and rrnL genes, contributes exclusively to T. cosgrovei mtDNA size variation. Within this region, mtDNA coding genes and putative nonfunctional sequences have accumulated substitutions and are duplicated and rearranged to varying extents. Hypervariation at this level has enabled a first insight into the life history of T. cosgrovei. In five A. vulgare hosts infected with multiple nematodes, four carried nematodes with identical mtDNA haplotypes, suggesting that hosts may become infected by ingesting a recently hatched egg clutch or become parasitized by individuals from the same brood prior to dispersal of siblings within the soil. PMID:17435228

  7. A synonymous polymorphism in a common MDR1 (ABCB1) haplotype shapes protein function

    PubMed Central

    Fung, King Leung; Gottesman, Michael M.

    2009-01-01

    The MDR1 (ABCB1) gene encodes a membrane-bound transporter that actively effluxes a wide range of compounds from cells. The overexpression of MDR1 by multidrug-resistant cancer cells is a serious impediment to chemotherapy. MDR1 is expressed in various tissues to protect them from the adverse effect of toxins. The pharmacokinetics of drugs that are also MDR1 substrates also influence disease outcome and treatment efficacy. Although MDR1 is a well conserved gene, there is increasing evidence that its polymorphisms affect substrate specificity. Three single nucleotide polymorphisms (SNPs) occur frequently and have strong linkage, creating a common haplotype at positions 1236C>T (G412G), 2677G>T (A893S) and 3435C>T (I1145I). The frequency of the synonymous 3435C>T polymorphism has been shown to vary significantly according to ethnicity. Existing literature suggests that the haplotype plays a role in response to drugs and disease susceptibility. This review summarizes recent findings on the 3435C>T polymorphism of MDR1 and the haplotype to which it belongs. A possible molecular mechanism of action by ribosome stalling that can change protein structure and function by altering protein folding is discussed. PMID:19285158

  8. Large-Scale SNP Marker Development and Genotyping in Oat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, our goals are to develop genome-wide SNP markers using next generation sequencing technologies and to apply a highly parallel SNP genotyping system developed by Illumina for genetics and breeding applications in oat. The large amount of DNA sequence sources generated from cDNAs and Di...

  9. SNPConvert: SNP Array Standardization and Integration in Livestock Species

    PubMed Central

    Nicolazzi, Ezequiel Luis; Marras, Gabriele; Stella, Alessandra

    2016-01-01

    One of the main advantages of single nucleotide polymorphism (SNP) array technology is providing genotype calls for a specific number of SNP markers at a relatively low cost. Since its first application in animal genetics, the number of available SNP arrays for each species has been constantly increasing. However, conversely to that observed in whole genome sequence data analysis, SNP array data does not have a common set of file formats or coding conventions for allele calling. Therefore, the standardization and integration of SNP array data from multiple sources have become an obstacle, especially for users with basic or no programming skills. Here, we describe the difficulties related to handling SNP array data, focusing on file formats, SNP allele coding, and mapping. We also present SNPConvert suite, a multi-platform, open-source, and user-friendly set of tools to overcome these issues. This tool, which can be integrated with open-source and open-access tools already available, is a first step towards an integrated system to standardize and integrate any type of raw SNP array data. The tool is available at: https://github. com/nicolazzie/SNPConvert.git. PMID:27600083

  10. SNPConvert: SNP Array Standardization and Integration in Livestock Species.

    PubMed

    Nicolazzi, Ezequiel Luis; Marras, Gabriele; Stella, Alessandra

    2016-01-01

    One of the main advantages of single nucleotide polymorphism (SNP) array technology is providing genotype calls for a specific number of SNP markers at a relatively low cost. Since its first application in animal genetics, the number of available SNP arrays for each species has been constantly increasing. However, conversely to that observed in whole genome sequence data analysis, SNP array data does not have a common set of file formats or coding conventions for allele calling. Therefore, the standardization and integration of SNP array data from multiple sources have become an obstacle, especially for users with basic or no programming skills. Here, we describe the difficulties related to handling SNP array data, focusing on file formats, SNP allele coding, and mapping. We also present SNPConvert suite, a multi-platform, open-source, and user-friendly set of tools to overcome these issues. This tool, which can be integrated with open-source and open-access tools already available, is a first step towards an integrated system to standardize and integrate any type of raw SNP array data. The tool is available at: https://github. com/nicolazzie/SNPConvert.git. PMID:27600083

  11. Accelerating genetic improvement with SNP chips and DNA sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of high-density single nucleotide polymorphism (SNP) assays is expected to have a profound impact on genetic progress in the U.S. dairy industry. In the 16 months since its initial availability, the Illumina BovineSNP50 BeadChip has been used to genotype nearly 20,000 Holsteins. Thes...

  12. Association of interleukin-1 gene cluster polymorphisms and haplotypes with multiple sclerosis in an Iranian population.

    PubMed

    Khosravi, Ayyoob; Javan, Bita; Tabatabaiefar, Mohammad Amin; Ebadi, Hamid; Fathi, Davood; Shahbazi, Majid

    2015-11-15

    Multiple sclerosis (MS) is a multi-factorial autoimmune disease of the central nervous system. The exact etiology of MS is still unknown. Due to the important roles that cytokines play as mediators in immune and inflammatory responses, we have evaluated the association of IL-1 gene cluster polymorphisms and haplotypes with MS susceptibility in 306 unrelated MS patients and 312 healthy matched controls. A significant association was found for the IL-1β +3953 T allele [OR=1.43, 95% CI (1.14-1.79), P value=0.002, Pc=0.01] and for IL-1β +3953 T/T genotype and MS risk [OR=1.92, 95% CI (1.25-2.96), P value=0.005, Pc=0.01]. Interestingly, the genotypes of the polymorphisms remained significant under recessive, co-recessive and dominant models. However, no significant differences were found between MS patients and controls in the genotype and allele frequencies of the IL-1β -511, -31 and IL-1Ra polymorphisms. Haplotype analysis for IL-1β -31 and IL-1β -511, with moderate linkage disequilibrium (LD), using the EM algorithm revealed a significant global association of haplotype differences between the two groups. Lower presence of two haplotypes (H3: C-T and H4: T-C) was observed in the MS patients than healthy controls. However, after applying Bonferroni's correction the differences were not significant. To our knowledge, this is the first study reporting the association of the IL-1β +3953 gene polymorphism and MS susceptibility. PMID:26531703

  13. Characterization of ancestral and derived Y-chromosome haplotypes of New World native populations.

    PubMed Central

    Bianchi, N O; Catanesi, C I; Bailliet, G; Martinez-Marignac, V L; Bravi, C M; Vidal-Rioja, L B; Herrera, R J; López-Camelo, J S

    1998-01-01

    We analyze the allelic polymorphisms in seven Y-specific microsatellite loci and a Y-specific alphoid system with 27 variants (alphah I-XXVII), in a total of 89 Y chromosomes carrying the DYS199T allele and belonging to populations representing Amerindian and Na-Dene linguistic groups. Since there are no indications of recurrence for the DYS199C-->T transition, it is assumed that all DYS199T haplotypes derive from a single individual in whom the C-->T mutation occurred for the first time. We identified both the ancestral founder haplotype, 0A, of the DYS199T lineage and seven derived haplogroups diverging from the ancestral one by one to seven mutational steps. The 0A haplotype (5.7% of Native American chromosomes) had the following constitution: DYS199T, alphah II, DYS19/13, DYS389a/10, DYS389b/27, DYS390/24, DYS391/10, DYS392/14, and DYS393/13 (microsatellite alleles are indicated as number of repeats). We analyzed the Y-specific microsatellite mutation rate in 1,743 father-son transmissions, and we pooled our data with data in the literature, to obtain an average mutation rate of.0012. We estimated that the 0A haplotype has an average age of 22,770 years (minimum 13,500 years, maximum 58,700 years). Since the DYS199T allele is found with high frequency in Native American chromosomes, we propose that 0A is one of the most prevalent founder paternal lineages of New World aborigines. PMID:9837838

  14. Insights into HLA-G Genetics Provided by Worldwide Haplotype Diversity

    PubMed Central

    Castelli, Erick C.; Ramalho, Jaqueline; Porto, Iane O. P.; Lima, Thálitta H. A.; Felício, Leandro P.; Sabbagh, Audrey; Donadi, Eduardo A.; Mendes-Junior, Celso T.

    2014-01-01

    Human leukocyte antigen G (HLA-G) belongs to the family of non-classical HLA class I genes, located within the major histocompatibility complex (MHC). HLA-G has been the target of most recent research regarding the function of class I non-classical genes. The main features that distinguish HLA-G from classical class I genes are (a) limited protein variability, (b) alternative splicing generating several membrane bound and soluble isoforms, (c) short cytoplasmic tail, (d) modulation of immune response (immune tolerance), and (e) restricted expression to certain tissues. In the present work, we describe the HLA-G gene structure and address the HLA-G variability and haplotype diversity among several populations around the world, considering each of its major segments [promoter, coding, and 3′ untranslated region (UTR)]. For this purpose, we developed a pipeline to reevaluate the 1000Genomes data and recover miscalled or missing genotypes and haplotypes. It became clear that the overall structure of the HLA-G molecule has been maintained during the evolutionary process and that most of the variation sites found in the HLA-G coding region are either coding synonymous or intronic mutations. In addition, only a few frequent and divergent extended haplotypes are found when the promoter, coding, and 3′UTRs are evaluated together. The divergence is particularly evident for the regulatory regions. The population comparisons confirmed that most of the HLA-G variability has originated before human dispersion from Africa and that the allele and haplotype frequencies have probably been shaped by strong selective pressures. PMID:25339953

  15. Haplotype association analysis of genes within the WNT signalling pathways in diabetic nephropathy

    PubMed Central

    2013-01-01

    Background Renal interstitial fibrosis and glomerular sclerosis are hallmarks of diabetic nephropathy (DN) and several studies have implicated members of the WNT pathways in these pathological processes. This study comprehensively examined common genetic variation within the WNT pathway for association with DN. Methods Genes within the WNT pathways were selected on the basis of nominal significance and consistent direction of effect in the GENIE meta-analysis dataset. Common SNPs and common haplotypes were examined within the selected WNT pathway genes in a white population with type 1 diabetes, discordant for DN (cases: n = 718; controls: n = 749). SNPs were genotyped using Sequenom or Taqman assays. Association analyses were performed using PLINK, to compare allele and haplotype frequencies in cases and controls. Correction for multiple testing was performed by either permutation testing or using false discovery rate. Results A logistic regression model including collection centre, duration of diabetes, and average HbA1c as covariates highlighted three SNPs in GSK3B (rs17810235, rs17471, rs334543), two in DAAM1 (rs1253192, rs1252906) and one in NFAT5 (rs17297207) as being significantly (P < 0.05) associated with DN, however these SNPs did not remain significant after correction for multiple testing. Logistic regression of haplotypes, with ESRD as the outcome, and pairwise interaction analyses did not yield any significant results after correction for multiple testing. Conclusions These results indicate that both common SNPs and common haplotypes of WNT pathway genes are not strongly associated with DN. However, this does not completely exclude these or the WNT pathways from association with DN, as unidentified rare genetic or copy number variants could still contribute towards the genetic architecture of DN. PMID:23777469

  16. A haplotype method detects diverse scenarios of local adaptation from genomic sequence variation.

    PubMed

    Lange, Jeremy D; Pool, John E

    2016-07-01

    Identifying genomic targets of population-specific positive selection is a major goal in several areas of basic and applied biology. However, it is unclear how often such selection should act on new mutations versus standing genetic variation or recurrent mutation, and furthermore, favoured alleles may either become fixed or remain variable in the population. Very few population genetic statistics are sensitive to all of these modes of selection. Here, we introduce and evaluate the Comparative Haplotype Identity statistic (χMD ), which assesses whether pairwise haplotype sharing at a locus in one population is unusually large compared with another population, relative to genomewide trends. Using simulations that emulate human and Drosophila genetic variation, we find that χMD is sensitive to a wide range of selection scenarios, and for some very challenging cases (e.g. partial soft sweeps), it outperforms other two-population statistics. We also find that, as with FST , our haplotype approach has the ability to detect surprisingly ancient selective sweeps. Particularly for the scenarios resembling human variation, we find that χMD outperforms other frequency- and haplotype-based statistics for soft and/or partial selective sweeps. Applying χMD and other between-population statistics to published population genomic data from D. melanogaster, we find both shared and unique genes and functional categories identified by each statistic. The broad utility and computational simplicity of χMD will make it an especially valuable tool in the search for genes targeted by local adaptation. PMID:27135633

  17. Atomic Force Microscopy for DNA SNP Identification

    NASA Astrophysics Data System (ADS)

    Valbusa, Ugo; Ierardi, Vincenzo

    The knowledge of the effects of single-nucleotide polymorphisms (SNPs) in the human genome greatly contributes to better comprehension of the relation between genetic factors and diseases. Sequence analysis of genomic DNA in different individuals reveals positions where variations that involve individual base substitutions can occur. Single-nucleotide polymorphisms are highly abundant and can have different consequences at phenotypic level. Several attempts were made to apply atomic force microscopy (AFM) to detect and map SNP sites in DNA strands. The most promising approach is the study of DNA mutations producing heteroduplex DNA strands and identifying the mismatches by means of a protein that labels the mismatches. MutS is a protein that is part of a well-known complex of mismatch repair, which initiates the process of repairing when the MutS binds to the mismatched DNA filament. The position of MutS on the DNA filament can be easily recorded by means of AFM imaging.

  18. Mitochondrial haplotype analysis for differentiation of isolates of Phytophthora cinnamomi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While Phytophthora cinnamomi is heterothallic, there are few instances of successful crossing in laboratory experiments and analysis of field populations indicates a clonally reproducing population. In the absence of sexual recombination the ability to monitor mitochondrial haplotypes may provide a...

  19. Y-chromosome STR haplotypes in males from Greenland.

    PubMed

    Hallenberg, Charlotte; Tomas, Carmen; Simonsen, Bo; Morling, Niels

    2009-09-01

    A total of 272 males from Greenland were typed for 11 Y-chromosome STRs DYS19, DYS385a/b, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439 with the PowerPlex Y System (Promega). A total of 146 different haplotypes were observed and the haplotype diversity was 0.9887. The number of haplotypes seen once was 108 and the most common haplotype was observed in 12 males. A significant F(ST) value was observed (F(ST)=0.012, P<0.00001) when comparing the population of 15 locations in Greenland assigned to 7 groups. The significance could mainly be attributed to the subpopulation of males from Tasiilaq (East of Greenland). The R(ST) value was not statistically significant (R(ST)=0.016, P=0.15). PMID:19647703

  20. Association of a bovine prion gene haplotype with atypical BSE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Atypical bovine spongiform encephalopathies (BSEs) are recently recognized prion diseases of cattle. Atypical BSEs are rare; approximately 30 cases have been identified worldwide. We tested prion gene (PRNP) haplotypes for an association with atypical BSE. Methodology/Principal Findin...

  1. De novo assembly of a haplotype-resolved human genome.

    PubMed

    Cao, Hongzhi; Wu, Honglong; Luo, Ruibang; Huang, Shujia; Sun, Yuhui; Tong, Xin; Xie, Yinlong; Liu, Binghang; Yang, Hailong; Zheng, Hancheng; Li, Jian; Li, Bo; Wang, Yu; Yang, Fang; Sun, Peng; Liu, Siyang; Gao, Peng; Huang, Haodong; Sun, Jing; Chen, Dan; He, Guangzhu; Huang, Weihua; Huang, Zheng; Li, Yue; Tellier, Laurent C A M; Liu, Xiao; Feng, Qiang; Xu, Xun; Zhang, Xiuqing; Bolund, Lars; Krogh, Anders; Kristiansen, Karsten; Drmanac, Radoje; Drmanac, Snezana; Nielsen, Rasmus; Li, Songgang; Wang, Jian; Yang, Huanming; Li, Yingrui; Wong, Gane Ka-Shu; Wang, Jun

    2015-06-01

    The human genome is diploid, and knowledge of the variants on each chromosome is important for the interpretation of genomic information. Here we report the assembly of a haplotype-resolved diploid genome without using a reference genome. Our pipeline relies on fosmid pooling together with whole-genome shotgun strategies, based solely on next-generation sequencing and hierarchical assembly methods. We applied our sequencing method to the genome of an Asian individual and generated a 5.15-Gb assembled genome with a haplotype N50 of 484 kb. Our analysis identified previously undetected indels and 7.49 Mb of novel coding sequences that could not be aligned to the human reference genome, which include at least six predicted genes. This haplotype-resolved genome represents the most complete de novo human genome assembly to date. Application of our approach to identify individual haplotype differences should aid in translating genotypes to phenotypes for the development of personalized medicine. PMID:26006006

  2. Associations of Haplotypes Upstream of IRS1 with Insulin Resistance, Type 2 Diabetes, Dyslipidemia, Preclinical Atherosclerosis, and Skeletal Muscle LOC646736 mRNA Levels

    PubMed Central

    Soyal, Selma M.; Felder, Thomas; Auer, Simon; Oberkofler, Hannes; Iglseder, Bernhard; Paulweber, Bernhard; Dossena, Silvia; Nofziger, Charity; Paulmichl, Markus; Esterbauer, Harald; Krempler, Franz; Patsch, Wolfgang

    2015-01-01

    The genomic region ~500 kb upstream of IRS1 has been implicated in insulin resistance, type 2 diabetes, adverse lipid profile, and cardiovascular risk. To gain further insight into this chromosomal region, we typed four SNPs in a cross-sectional cohort and subjects with type 2 diabetes recruited from the same geographic region. From 16 possible haplotypes, 6 haplotypes with frequencies >0.01 were observed. We identified one haplotype that was protective against insulin resistance (determined by HOMA-IR and fasting plasma insulin levels), type 2 diabetes, an adverse lipid profile, increased C-reactive protein, and asymptomatic atherosclerotic disease (assessed by intima media thickness of the common carotid arteries). BMI and total adipose tissue mass as well as visceral and subcutaneous adipose tissue mass did not differ between the reference and protective haplotypes. In 92 subjects, we observed an association of the protective haplotype with higher skeletal muscle mRNA levels of LOC646736, which is located in the same haplotype block as the informative SNPs and is mainly expressed in skeletal muscle, but only at very low levels in liver or adipose tissues. These data suggest a role for LOC646736 in human insulin resistance and warrant further studies on the functional effects of this locus. PMID:26090471

  3. A common haplotype of carnitine palmitoyltransferase 1b is associated with the metabolic syndrome.

    PubMed

    Auinger, A; Rubin, D; Sabandal, M; Helwig, U; Rüther, A; Schreiber, S; Foelsch, U R; Döring, F; Schrezenmeir, J

    2013-03-14

    The carnitine palmitoyltransferase (CPT) enzyme system facilitates the transport of long-chain fatty acids into mitochondria to provide substrates for β-oxidation. We performed an analysis including three coding SNP in the muscle isoform of the CPT1b gene (rs3213445, rs2269383 and rs470117) and one coding SNP in the CPT2 gene (rs1799821) to find associations with traits of the metabolic syndrome (MetS). Male participants (n 755) from the Metabolic Intervention Cohort Kiel were genotyped and phenotyped for features of the MetS. Participants underwent a glucose tolerance test and a postprandial assessment of metabolic variables after a standardised mixed meal. Carriers of the rare CPT1b 66V (rs3213445) allele had significantly higher γ-glutamyl transpeptidase (GGT), glutamic oxaloacetic transaminase (GOT) and glutamic pyruvate transaminase (GPT) activities (P< 0·0001, P= 0·03 and P= 0·048, respectively) and a higher fatty liver index (FLI, P= 0·026). Fasting and postprandial TAG (P= 0·007 and P= 0·009, respectively) and fasting glucose (P= 0·012) were significantly higher in 66V-allele carriers. The insulin sensitivity index determined after a glucose load was lower in those subjects (P= 0·005). Total cholesterol (P= 0·051) and LDL-cholesterol (P= 0·062) tended to be higher in 66V-allele carriers when compared with I66I homozygotes. Homozygosity of the rare K531E allele presented with lower GGT and GOT activities (P= 0·011 and P= 0·027, respectively). E531E homozygotes tended to have lower GPT and FLI (P= 0·078 and P= 0·052, respectively). CPT2 V368I (rs1799821) genotypic groups did not differ in the investigated anthropometric and metabolic parameters. The present results confirm the association of CPT1b coding polymorphisms with the MetS, with a deleterious effect of the CPT1b I66V and a protective impact of the CPT1b K531E SNP, whereas haplotype analysis indicates a relevance of the E531K polymorphism only. PMID:22809552

  4. Haplotype hitchhiking promotes trait coselection in Brassica napus.

    PubMed

    Qian, Lunwen; Qian, Wei; Snowdon, Rod J

    2016-07-01

    Local haplotype patterns surrounding densely spaced DNA markers with significant trait associations can reveal information on selective sweeps and genome diversity associated with important crop traits. Relationships between haplotype and phenotype diversity, coupled with analysis of gene content in conserved haplotype blocks, can provide insight into coselection for nonrelated traits. We performed genome-wide analysis of haplotypes associated with the important physiological and agronomic traits leaf chlorophyll and seed glucosinolate content, respectively, in the major oilseed crop species Brassica napus. A locus on chromosome A01 showed opposite effects on leaf chlorophyll content and seed glucosinolate content, attributed to strong linkage disequilibrium (LD) between orthologues of the chlorophyll biosynthesis genes EARLY LIGHT-INDUCED PROTEIN and CHLOROPHYLL SYNTHASE, and the glucosinolate synthesis gene ATP SULFURYLASE 1. Another conserved haplotype block, on chromosome A02, contained a number of chlorophyll-related genes in LD with orthologues of the key glucosinolate biosynthesis genes METHYLTHIOALKYMALATE SYNTHASE-LIKE 1 and 3. Multigene haplogroups were found to have a significantly greater contribution to variation for chlorophyll content than haplotypes for any single gene, suggesting positive effects of additive locus accumulation. Detailed reanalysis of population substructure revealed a clade of ten related accessions exhibiting high leaf chlorophyll and low seed glucosinolate content. These accessions each carried one of the above-mentioned haplotypes from A01 or A02, generally in combination with further chlorophyll-associated haplotypes from chromosomes A05 and/or C05. The phenotypic rather than pleiotropic correlations between leaf chlorophyll content index and seed GSL suggest that LD may have led to inadvertent coselection for these two traits. PMID:26800855

  5. Twelve short tandem repeat loci Y chromosome haplotypes: genetic analysis on populations residing in North America.

    PubMed

    Budowle, Bruce; Adamowicz, Mike; Aranda, Xavier G; Barna, Charles; Chakraborty, Ranajit; Cheswick, Dan; Dafoe, Bradley; Eisenberg, Arthur; Frappier, Roger; Gross, Ann Marie; Ladd, Carll; Lee, Hee-Suk; Milne, Scott C; Meyers, Carole; Prinz, Mechthild; Richard, Melanie L; Saldanha, Gabriela; Tierney, Amy A; Viculis, Lori; Krenke, Benjamin E

    2005-05-28

    an estimate of the rarity of the Y-haplotype. Because the Y-STR loci are not all in disequilibrium to the same extent, the counting method is a very conservative approach. The data also support that autosomal STR frequencies can be multiplied by the upper bound frequency estimate of a Y-haplotype in the individual population group or those pooled into major population groups (i.e., Caucasian, African American, Hispanic, and Asian). These analyses support use of the haplotype population data for estimating Y-STR profile frequencies for populations residing in North America. PMID:15837004

  6. Single nucleotide polymorphism (SNP) variation of wolves (Canis lupus) in Southeast Alaska and comparison with wolves, dogs, and coyotes in North America.

    PubMed

    Cronin, Matthew A; Cánovas, Angela; Bannasch, Danika L; Oberbauer, Anita M; Medrano, Juan F

    2015-01-01

    There is considerable interest in the genetics of wolves (Canis lupus) because of their close relationship to domestic dogs (C. familiaris) and the need for informed conservation and management. This includes wolf populations in Southeast Alaska for which we determined genotypes of 305 wolves at 173662 single nucleotide polymorphism (SNP) loci. After removal of invariant and linked SNP, 123801 SNP were used to quantify genetic differentiation of wolves in Southeast Alaska and wolves, coyotes (C. latrans), and dogs from other areas in North America. There is differentiation of SNP allele frequencies between the species (wolves, coyotes, and dogs), although differentiation is relatively low between some wolf and coyote populations. There are varying levels of differentiation among populations of wolves, including low differentiation of wolves in interior Alaska, British Columbia, and the northern US Rocky Mountains. There is considerable differentiation of SNP allele frequencies of wolves in Southeast Alaska from wolves in other areas. However, wolves in Southeast Alaska are not a genetically homogeneous group and there are comparable levels of genetic differentiation among areas within Southeast Alaska and between Southeast Alaska and other geographic areas. SNP variation and other genetic data are discussed regarding taxonomy and management. PMID:25429025

  7. Haplotype Reconstruction in Large Pedigrees with Many Untyped Individuals

    NASA Astrophysics Data System (ADS)

    Li, Xin; Li, Jing

    Haplotypes, as they specify the linkage patterns between dispersed genetic variations, provide important information for understanding the genetics of human traits. However haplotypes are not directly available from current genotyping platforms, and hence there are extensive investigations of computational methods to recover such information. Two major computational challenges arising in current family-based disease studies are large family sizes and many ungenotyped family members. Traditional haplotyping methods can neither handle large families nor families with missing members. In this paper, we propose a method which addresses these issues by integrating multiple novel techniques. The method consists of three major components: pairwise identical-bydescent (IBD) inference, global IBD reconstruction and haplotype restoring. By reconstructing the global IBD of a family from pairwise IBD and then restoring the haplotypes based on the inferred IBD, this method can scale to large pedigrees, and more importantly it can handle families with missing members. Compared with existing methods, this method demonstrates much higher power to recover haplotype information, especially in families with many untyped individuals.

  8. iXora: exact haplotype inferencing and trait association

    PubMed Central

    2013-01-01

    Background We address the task of extracting accurate haplotypes from genotype data of individuals of large F1 populations for mapping studies. While methods for inferring parental haplotype assignments on large F1 populations exist in theory, these approaches do not work in practice at high levels of accuracy. Results We have designed iXora (Identifying crossovers and recombining alleles), a robust method for extracting reliable haplotypes of a mapping population, as well as parental haplotypes, that runs in linear time. Each allele in the progeny is assigned not just to a parent, but more precisely to a haplotype inherited from the parent. iXora shows an improvement of at least 15% in accuracy over similar systems in literature. Furthermore, iXora provides an easy-to-use, comprehensive environment for association studies and hypothesis checking in populations of related individuals. Conclusions iXora provides detailed resolution in parental inheritance, along with the capability of handling very large populations, which allows for accurate haplotype extraction and trait association. iXora is available for non-commercial use from http://researcher.ibm.com/project/3430. PMID:23742238

  9. Association of a Bovine Prion Gene Haplotype with Atypical BSE

    PubMed Central

    Clawson, Michael L.; Richt, Juergen A.; Baron, Thierry; Biacabe, Anne-Gaëlle; Czub, Stefanie; Heaton, Michael P.; Smith, Timothy P. L.; Laegreid, William W.

    2008-01-01

    Background Atypical bovine spongiform encephalopathies (BSEs) are recently recognized prion diseases of cattle. Atypical BSEs are rare; approximately 30 cases have been identified worldwide. We tested prion gene (PRNP) haplotypes for an association with atypical BSE. Methodology/Principle Findings Haplotype tagging polymorphisms that characterize PRNP haplotypes from the promoter region through the three prime untranslated region of exon 3 (25.2 kb) were used to determine PRNP haplotypes of six available atypical BSE cases from Canada, France and the United States. One or two copies of a distinct PRNP haplotype were identified in five of the six cases (p = 1.3×10−4, two-tailed Fisher's exact test; CI95% 0.263–0.901, difference between proportions). The haplotype spans a portion of PRNP that includes part of intron 2, the entire coding region of exon 3 and part of the three prime untranslated region of exon 3 (13 kb). Conclusions/Significance This result suggests that a genetic determinant in or near PRNP may influence susceptibility of cattle to atypical BSE. PMID:18350166

  10. Molecular characterization of a long range haplotype affecting protein yield and mastitis susceptibility in Norwegian Red cattle

    PubMed Central

    2011-01-01

    Background Previous fine mapping studies in Norwegian Red cattle (NRC) in the region 86-90.4 Mb on Bos taurus chromosome 6 (BTA6) has revealed a quantitative trait locus (QTL) for protein yield (PY) around 88 Mb and a QTL for clinical mastitis (CM) around 90 Mb. The close proximity of these QTLs may partly explain the unfavorable genetic correlation between these two traits in NRC. A long range haplotype covering this region was introduced into the NRC population through the importation of a Holstein-Friesian bull (1606 Frasse) from Sweden in the 1970s. It has been suggested that this haplotype has a favorable effect on milk protein content but an unfavorable effect on mastitis susceptibility. Selective breeding for milk production traits is likely to have increased the frequency of this haplotype in the NRC population. Results Association mapping for PY and CM in NRC was performed using genotypes from 556 SNPs throughout the region 86-97 Mb on BTA6 and daughter-yield-deviations (DYDs) from 2601 bulls made available from the Norwegian dairy herd recording system. Highest test scores for PY were found for single-nucleotide polymorphisms (SNPs) within and surrounding the genes CSN2 and CSN1S2, coding for the β-casein and αS2-casein proteins. High coverage re-sequencing by high throughput sequencing technology enabled molecular characterization of a long range haplotype from 1606 Frasse encompassing these two genes. Haplotype analysis of a large number of descendants from this bull indicated that the haplotype was not markedly disrupted by recombination in this region. The haplotype was associated with both increased milk protein content and increased susceptibility to mastitis, which might explain parts of the observed genetic correlation between PY and CM in NRC. Plausible causal polymorphisms affecting PY were detected in the promoter region and in the 5'-flanking UTR of CSN1S2. These polymorphisms could affect transcription or translation of CSN1S2 and thereby

  11. Population data for Y-chromosome haplotypes defined by 17 STRs in South-East Romania.

    PubMed

    Stanciu, Florin; Cuţăr, Veronica; Pîrlea, Sorina; Stoian, Veronica; Stoian, Ionel Marius; Sevastre, Olivia; Popescu, Oana Raluca

    2010-09-01

    Haplotypes and allele frequencies for 17 STR loci included in AmpFlSTR YFiler kit (DYS456, DYS389I, DYS390, DYS389II, DYS458, DYS19, DYS385a/b, DYS393, DYS391, DYS439, DYS635, DYS392, Y GATAH4, DYS437, DYS438 and DYS448) were determined in a sample of 122 unrelated males living in the South-East Romania. Genetic distances had been calculated and dendrograms had been generated for South-East Romanian population and other eighteen surrounding populations. PMID:20621540

  12. HLA alleles and haplotypes among the Lakota Sioux: report of the ASHI minority workshops, part III.

    PubMed

    Leffell, Mary S; Fallin, M Daniele; Hildebrand, William H; Cavett, Joshua W; Iglehart, Brian A; Zachary, Andrea A

    2004-01-01

    Human leukocyte antigen (HLA) class I and II alleles were defined for 302 Lakota Sioux American Indians as part of the American Society for Histocompatibility and Immunogenetics coordinated studies on minority populations. The study group was comprised of adult volunteers from the Cheyenne River and Ogala Sioux tribes residing, respectively, on the Cheyenne River and Pine Ridge Reservations in South Dakota. Of the participants, 263 (87%) claimed full American Indian ancestry through both maternal and paternal grandparents. The study group included 25 nuclear families that were informative for genotyping. HLA phenotypes from 202 adults with no other known first-degree relative included in the study were used for calculation of allele and haplotype frequencies by maximum likelihood estimation. HLA-A, -B, and -Cw alleles were found to be in Hardy Weinberg equilibrium. Deviation from equilibrium was observed for DRB1 alleles (p=0.01), but could be attributed to the sample size and the occurrence of some genotypes with low expected frequencies. Polymorphism among the Sioux was limited with four to seven alleles comprising >80% of those observed at each locus. Several alleles were found at high frequency (0.05-0.30) among the Sioux that are also prevalent in other Native Americans and Alaska Natives, including: A*2402, *3101, and *0206; B*3501,*3901, *5101, and *2705; Cw*0702, *0404, and *03041; DRB1*0407, *0404, *1402, and *16021; and DQB1*0301, *0302, and *0402. DRB1*0811, which has been only previously described in Navajo and Tlingit Indians, was found to occur at a frequency of 0.119 among the Sioux. Two new alleles were defined among the Sioux: Cw*0204 and DRB1*040703, which were found in two and four individuals, respectively. In the haplotype analyses, significant linkage disequilibrium (p<0.00001) was seen in all pairwise comparisons of loci and numerous two and three locus haplotypes were found to have strong, positive linkage disequilibrium values. The two most

  13. Identifying four Trypanosoma cruzi I isolate haplotypes from different geographic regions in Colombia.

    PubMed

    Herrera, Claudia; Bargues, M Dolores; Fajardo, Anabella; Montilla, Marleny; Triana, Omar; Vallejo, Gustavo Adolfo; Guhl, Felipe

    2007-07-01

    Trypanosoma cruzi has been classified into the groups T. cruzi I and T. cruzi II. The latter is subdivided into five smaller lineages based on multilocus enzyme electrophoresis and random amplified polymorphic DNA, designated as IIa-IIe, which shows correspondence with rRNA/mini-exon lineages. Twelve previously characterised T. cruzi isolates from different hosts, including humans, Didelphis marsupialis, and triatomines were analysed to establish genetic variability in T. cruzi group T. cruzi I isolates from different geographical regions of Colombia. DNA samples were sequenced based on the mini-exon gene intergenic region. Sequences were analysed using Clustal W, Staden 1.5 and MEGA3 software, and using reported sequences from the GenBank as reference. The genetic distances were analysed using Kimura's two-parameter model. The isolates' joint alignment was of 350bp, and the calculated nucleotide divergence was of 17.5%. The differences consisted of 23 transitions (7.2%), 14 transversions (4.4%) and 19 insertion-deletions (5.9%). The Colombian T cruzi I isolates revealed sufficient genetic variability for us to propose the existence of four haplotypes identified through single nucleotide polymorphism (SNP) and insertion/deletion found in the mini-exon gene's non-transcribed spacer intergenic region. PMID:17287152

  14. HLA-A-B-C-DRB1-DQB1 phased haplotypes in 124 Nigerian families indicate extreme HLA diversity and low linkage disequilibrium in Central-West Africa.

    PubMed

    Testi, M; Battarra, M; Lucarelli, G; Isgro, A; Morrone, A; Akinyanju, O; Wakama, T; Nunes, J M; Andreani, M; Sanchez-Mazas, A

    2015-10-01

    The simultaneous typing of five-HLA loci at high resolution and the availability of pedigree data allowed us to characterize extended five-locus phased haplotypes in 124 Nigerian families and to compare the observed frequencies with those expected by an expectation-maximization algorithm for unphased data. Despite the occurrence of some frequent alleles at each locus (e.g. B*53:01, which is assumed to protect against Plasmodium falciparum), as many as 82% of the sampled individuals carry two unique five-locus haplotypes and only three extended haplotypes with frequency above 1% exhibit significant linkage disequilibrium. Although preliminary, these results reveal an extreme level of HLA diversity in the Nigerian population, which reflects both its multi-ethnic composition and the very ancient demographic history of African populations. PMID:26300115

  15. Genetic association analysis of 300 genes identifies a risk haplotype in SLC18A2 for post-traumatic stress disorder in two independent samples.

    PubMed

    Solovieff, Nadia; Roberts, Andrea L; Ratanatharathorn, Andrew; Haloosim, Michelle; De Vivo, Immaculata; King, Anthony P; Liberzon, Israel; Aiello, Allison; Uddin, Monica; Wildman, Derek E; Galea, Sandro; Smoller, Jordan W; Purcell, Shaun M; Koenen, Karestan C

    2014-07-01

    The genetic architecture of post-traumatic stress disorder (PTSD) remains poorly understood with the vast majority of genetic association studies reporting on single candidate genes. We conducted a large genetic study in trauma-exposed European-American women (N=2538; 845 PTSD cases, 1693 controls) by testing 3742 SNPs across more than 300 genes and conducting polygenic analyses using results from the Psychiatric Genome-Wide Association Studies Consortium (PGC). We tested the association between each SNP and two measures of PTSD, a severity score and diagnosis. We found a significant association between PTSD (diagnosis) and SNPs (top SNP: rs363276, odds ratio (OR)=1.4, p=2.1E-05) in SLC18A2 (vesicular monoamine transporter 2). A haplotype analysis of 9 SNPs in SLC18A2, including rs363276, identified a risk haplotype (CGGCGGAAG, p=0.0046), and the same risk haplotype was associated with PTSD in an independent cohort of trauma-exposed African-Americans (p=0.049; N=748, men and women). SLC18A2 is involved in transporting monoamines to synaptic vesicles and has been implicated in a number of neuropsychiatric disorders including major depression. Eight genes previously associated with PTSD had SNPs with nominally significant associations (p<0.05). The polygenic analyses suggested that there are SNPs in common between PTSD severity and bipolar disorder. Our data are consistent with a genetic architecture for PTSD that is highly polygenic, influenced by numerous SNPs with weak effects, and may overlap with mood disorders. Genome-wide studies with very large samples sizes are needed to detect these types of effects. PMID:24525708

  16. Genetic Association Analysis of 300 Genes Identifies a Risk Haplotype in SLC18A2 for Post-traumatic Stress Disorder in Two Independent Samples

    PubMed Central

    Solovieff, Nadia; Roberts, Andrea L; Ratanatharathorn, Andrew; Haloosim, Michelle; De Vivo, Immaculata; King, Anthony P; Liberzon, Israel; Aiello, Allison; Uddin, Monica; Wildman, Derek E; Galea, Sandro; Smoller, Jordan W; Purcell, Shaun M; Koenen, Karestan C

    2014-01-01

    The genetic architecture of post-traumatic stress disorder (PTSD) remains poorly understood with the vast majority of genetic association studies reporting on single candidate genes. We conducted a large genetic study in trauma-exposed European-American women (N=2538; 845 PTSD cases, 1693 controls) by testing 3742 SNPs across more than 300 genes and conducting polygenic analyses using results from the Psychiatric Genome-Wide Association Studies Consortium (PGC). We tested the association between each SNP and two measures of PTSD, a severity score and diagnosis. We found a significant association between PTSD (diagnosis) and SNPs (top SNP: rs363276, odds ratio (OR)=1.4, p=2.1E-05) in SLC18A2 (vesicular monoamine transporter 2). A haplotype analysis of 9 SNPs in SLC18A2, including rs363276, identified a risk haplotype (CGGCGGAAG, p=0.0046), and the same risk haplotype was associated with PTSD in an independent cohort of trauma-exposed African-Americans (p=0.049; N=748, men and women). SLC18A2 is involved in transporting monoamines to synaptic vesicles and has been implicated in a number of neuropsychiatric disorders including major depression. Eight genes previously associated with PTSD had SNPs with nominally significant associations (p<0.05). The polygenic analyses suggested that there are SNPs in common between PTSD severity and bipolar disorder. Our data are consistent with a genetic architecture for PTSD that is highly polygenic, influenced by numerous SNPs with weak effects, and may overlap with mood disorders. Genome-wide studies with very large samples sizes are needed to detect these types of effects. PMID:24525708

  17. Association and CpG SNP analysis of HTR4 polymorphisms with suicidal behavior in subjects with schizophrenia.

    PubMed

    Polsinelli, Gina; Zai, Clement C; Strauss, John; Kennedy, James L; De Luca, Vincenzo

    2013-02-01

    Suicide is a major contributor to the morbidity and mortality rates in schizophrenia. Genetic and epigenetic factors have been reported to modulate the risk for suicide although the precise mechanism and magnitude of these contributions is unknown. Previous research indicates that suicide attempters present abnormalities in the serotonergic system. The present study aimed to identify genetic and epigenetic risk variants of the serotonin 5-HT₄ receptor gene (HTR4) for suicidal behavior. We included 234 subjects diagnosed with schizophrenia. For this purpose, we analyzed 11 markers across HTR4 and performed genotype, haplotype and potential methylation analyses, correcting for clinical covariates and ethnic stratification. Three blocks were revealed from the LD analysis. Haplotypes in Block 3 were significantly associated with suicide attempt. The potential methylation analysis was not significant. Our results suggest that HTR4 polymorphisms may not play a major role in the susceptibility for suicidal behavior in subjects with schizophrenia. Moreover, although not significant, the CpG SNP potential methylation analysis would be informative for future methylation analysis on this gene. PMID:22842674

  18. The west side story: MEFV haplotype in Spanish FMF patients and controls, and evidence of high LD and a recombination "hot-spot" at the MEFV locus.

    PubMed

    Aldea, Anna; Calafell, Francesc; Aróstegui, Juan I; Lao, Oscar; Rius, Josefa; Plaza, Susana; Masó, Montserrat; Vives, Jordi; Buades, Joan; Yagüe, Jordi

    2004-04-01

    Mutations at the MEFV gene cause, with various degrees of penetrance, familial Mediterranean fever (FMF). This disease is more prevalent in the Middle East than elsewhere, and most studies have focused on those populations. However, FMF occurs also in the Western Mediterranean and these populations should be taken into account for a complete view of FMF. We have analyzed intragenic MEFV SNPs in Spanish and Chueta (descendants of converted Jews) FMF patients and controls, and this constitutes the first systematic survey of normal MEFV SNP haplotype structure and variability. Our findings have allowed us to systematize the nomenclature of MEFV haplotypes and show that there is strong linkage disequilibrium (LD) at the MEFV locus and an intragenic recombination hot spot. The high local LD, regardless the recombination hot spot, is responsible for the limited diversity of the MEFV control haplotypes found in the Spanish population and it suggests that it may be a common feature to all Mediterranean populations. The MEFV mutation spectrum in Spain is quite diverse, and similar to those of France and Italy. On the contrary, the Chueta spectrum was poorer and closer to that of North African Jews, suggesting a direct connection with the Jewish diaspora. PMID:15024744

  19. Complement factor H gene (CFH) polymorphisms C-257T, G257A and haplotypes are associated with protection against severe dengue phenotype, possible related with high CFH expression.

    PubMed

    Pastor, André F; Rodrigues Moura, Laís; Neto, José W D; Nascimento, Eduardo J M; Calzavara-Silva, Carlos E; Gomes, Ana Lisa V; Silva, Ana Maria da; Cordeiro, Marli T; Braga-Neto, Ulisses; Crovella, Sergio; Gil, Laura H V G; Marques, Ernesto T A; Acioli-Santos, Bartolomeu

    2013-09-01

    Four genetic polymorphisms located at the promoter (C-257T) and coding regions of CFH gene (exon 2 G257A, exon 14 A2089G and exon 19 G2881T) were investigated in 121 dengue patients (DENV-3) in order to assess the relationship between allele/haplotypes variants and clinical outcomes. A statistical value was found between the CFH-257T allele (TT/TC genotypes) and reduced susceptibility to severe dengue (SD). Statistical associations indicate that individuals bearing a T allele presented significantly higher protein levels in plasma. The -257T variant is located within a NF-κB binding site, suggesting that this variant might have effect on the ability of the CFH gene to respond to signals via the NF-κB pathway. The G257A allelic variant showed significant protection against severe dengue. When CFH haplotypes effect was considered, the ancestral CG/CG promoter-exon 2 SNP genotype showed significant risk to SD either in a general comparison (ancestral × all variant genotypes), as well as in individual genotypes comparison (ancestral × each variant genotype), where the most prevalent effect was observed in the CG/CG × CA/TG comparison. These findings support the involvement of -257T, 257A allele variants and haplotypes on severe dengue phenotype protection, related with high basal CFH expression. PMID:23747994

  20. Selection in the Making: A Worldwide Survey of Haplotypic Diversity Around a Causative Mutation in Porcine IGF2

    PubMed Central

    Ojeda, A.; Huang, L.-S.; Ren, J.; Angiolillo, A.; Cho, I.-C.; Soto, H.; Lemús-Flores, C.; Makuza, S. M.; Folch, J. M.; Pérez-Enciso, M.

    2008-01-01

    Domestic species allow us to study dramatic evolutionary changes at an accelerated rate due to the effectiveness of modern breeding techniques and the availability of breeds that have undergone distinct selection pressures. We present a worldwide survey of haplotype variability around a known causative mutation in porcine gene IGF2, which increases lean content. We genotyped 34 SNPs spanning 27 kb in 237 domestic pigs and 162 wild boars. Although the selective process had wiped out variability for at least 27 kb in the haplotypes carrying the mutation, there was no indication of an overall reduction in genetic variability of international vs. European local breeds; there was also no evidence of a reduction in variability caused by domestication. The haplotype structure and a plot of Tajima's D against the frequency of the causative mutation across breeds suggested a temporal pattern, where each breed corresponded to a different selective stage. This was observed comparing the haplotype neighbor-joining (NJ) trees of breeds that have undergone increasing selection pressures for leanness, e.g., European local breeds vs. Pietrain. These results anticipate that comparing current domestic breeds will decisively help to recover the genetic history of domestication and contemporary selective processes. PMID:18245828

  1. HapMap tag-SNP analysis confirms a role for COMT in schizophrenia risk and reveals a novel association.

    PubMed

    Voisey, J; Swagell, C D; Hughes, I P; Lawford, B R; Young, R M; Morris, C P

    2012-07-01

    Catechol-O-methyl transferase (COMT) encodes an enzyme involved in the metabolism of dopamine and maps to a commonly deleted region that increases schizophrenia risk. A non-synonymous polymorphism (rs4680) in COMT has been previously found to be associated with schizophrenia and results in altered activity levels of COMT. Using a haplotype block-based gene-tagging approach we conducted an association study of seven COMT single nucleotide polymorphisms (SNPs) in 160 patients with a DSM-IV diagnosis of schizophrenia and 250 controls in an Australian population. Two polymorphisms including rs4680 and rs165774 were found to be significantly associated with schizophrenia. The rs4680 results in a Val/Met substitution but the strongest association was shown by the novel SNP, rs165774, which may still be functional even though it is located in intron five. Individuals with schizophrenia were more than twice as likely to carry the GG genotype compared to the AA genotype for both the rs165774 and rs4680 SNPs. This association was slightly improved when males were analysed separately possibly indicating a degree of sexual dimorphism. Our results confirm that COMT is a good candidate for schizophrenia risk, by replicating the association with rs4680 and identifying a novel SNP association. PMID:20934310

  2. High-throughput bacterial SNP typing identifies distinct clusters of Salmonella Typhi causing typhoid in Nepalese children

    PubMed Central

    2010-01-01

    Background Salmonella Typhi (S. Typhi) causes typhoid fever, which remains an important public health issue in many developing countries. Kathmandu, the capital of Nepal, is an area of high incidence and the pediatric population appears to be at high risk of exposure and infection. Methods We recently defined the population structure of S. Typhi, using new sequencing technologies to identify nearly 2,000 single nucleotide polymorphisms (SNPs) that can be used as unequivocal phylogenetic markers. Here we have used the GoldenGate (Illumina) platform to simultaneously type 1,500 of these SNPs in 62 S. Typhi isolates causing severe typhoid in children admitted to Patan Hospital in Kathmandu. Results Eight distinct S. Typhi haplotypes were identified during the 20-month study period, with 68% of isolates belonging to a subclone of the previously defined H58 S. Typhi. This subclone was closely associated with resistance to nalidixic acid, with all isolates from this group demonstrating a resistant phenotype and harbouring the same resistance-associated SNP in GyrA (Phe83). A secondary clone, comprising 19% of isolates, was observed only during the second half of the study. Conclusions Our data demonstrate the utility of SNP typing for monitoring bacterial populations over a defined period in a single endemic setting. We provide evidence for genotype introduction and define a nalidixic acid resistant subclone of S. Typhi, which appears to be the dominant cause of severe pediatric typhoid in Kathmandu during the study period. PMID:20509974

  3. Whole-genome haplotyping by dilution, amplification, and sequencing

    PubMed Central

    Kaper, Fiona; Swamy, Sajani; Klotzle, Brandy; Munchel, Sarah; Cottrell, Joseph; Bibikova, Marina; Chuang, Han-Yu; Kruglyak, Semyon; Ronaghi, Mostafa; Eberle, Michael A.; Fan, Jian-Bing

    2013-01-01

    Standard whole-genome genotyping technologies are unable to determine haplotypes. Here we describe a method for rapid and cost-effective long-range haplotyping. Genomic DNA is diluted and distributed into multiple aliquots such that each aliquot receives a fraction of a haploid copy. The DNA template in each aliquot is amplified by multiple displacement amplification, converted into barcoded sequencing libraries using Nextera technology, and sequenced in multiplexed pools. To assess the performance of our method, we combined two male genomic DNA samples at equal ratios, resulting in a sample with diploid X chromosomes with known haplotypes. Pools of the multiplexed sequencing libraries were subjected to targeted pull-down of a 1-Mb contiguous region of the X-chromosome Duchenne muscular dystrophy gene. We were able to phase the Duchenne muscular dystrophy region into two contiguous haplotype blocks with a mean length of 494 kb. The haplotypes showed 99% agreement with the consensus base calls made by sequencing the individual DNAs. We subsequently used the strategy to haplotype two human genomes. Standard genomic sequencing to identify all heterozygous SNPs in the sample was combined with dilution-amplification–based sequencing data to resolve the phase of identified heterozygous SNPs. Using this procedure, we were able to phase >95% of the heterozygous SNPs from the diploid sequence data. The N50 for a Yoruba male DNA was 702 kb whereas the N50 for a European female DNA was 358 kb. Therefore, the strategy described here is suitable for haplotyping of a set of targeted regions as well as of the entire genome. PMID:23509297

  4. Whole-genome haplotyping by dilution, amplification, and sequencing.

    PubMed

    Kaper, Fiona; Swamy, Sajani; Klotzle, Brandy; Munchel, Sarah; Cottrell, Joseph; Bibikova, Marina; Chuang, Han-Yu; Kruglyak, Semyon; Ronaghi, Mostafa; Eberle, Michael A; Fan, Jian-Bing

    2013-04-01

    Standard whole-genome genotyping technologies are unable to determine haplotypes. Here we describe a method for rapid and cost-effective long-range haplotyping. Genomic DNA is diluted and distributed into multiple aliquots such that each aliquot receives a fraction of a haploid copy. The DNA template in each aliquot is amplified by multiple displacement amplification, converted into barcoded sequencing libraries using Nextera technology, and sequenced in multiplexed pools. To assess the performance of our method, we combined two male genomic DNA samples at equal ratios, resulting in a sample with diploid X chromosomes with known haplotypes. Pools of the multiplexed sequencing libraries were subjected to targeted pull-down of a 1-Mb contiguous region of the X-chromosome Duchenne muscular dystrophy gene. We were able to phase the Duchenne muscular dystrophy region into two contiguous haplotype blocks with a mean length of 494 kb. The haplotypes showed 99% agreement with the consensus base calls made by sequencing the individual DNAs. We subsequently used the strategy to haplotype two human genomes. Standard genomic sequencing to identify all heterozygous SNPs in the sample was combined with dilution-amplification-based sequencing data to resolve the phase of identified heterozygous SNPs. Using this procedure, we were able to phase >95% of the heterozygous SNPs from the diploid sequence data. The N50 for a Yoruba male DNA was 702 kb whereas the N50 for a European female DNA was 358 kb. Therefore, the strategy described here is suitable for haplotyping of a set of targeted regions as well as of the entire genome. PMID:23509297

  5. Effects of PON Polymorphisms and Haplotypes on Molecular Phenotype in Mexican-American Mothers and Children

    PubMed Central

    Huen, Karen; Barcellos, Lisa; Beckman, Kenneth; Rose, Sherri; Eskenazi, Brenda; Holland, Nina

    2010-01-01

    Paraoxonase 1 (PON1) prevents oxidation of low density lipoproteins and inactivates toxic oxon derivatives of organophosphate pesticides (OPs). Over 250 SNPs have been previously identified in the PON1 gene, yet studies of PON1 genetic variation focus primarily on a few promoter SNPs (-108,-162) and coding SNPs (192, 55). We sequenced the PON1 gene in 30 subjects from a Mexican-American birth cohort and identified 94 polymorphisms with minor allele frequencies > 5%, including several novel variants (6 SNPs, 1 insertion, 2 deletions). Variants of the PON1 gene and 3 SNPs from PON2 and PON3 were genotyped in 700 children and mothers from the same cohort. PON1 phenotype was established using two substrate-specific assays: arylesterase (AREase) and paraoxonase (POase). Twelve PON1 and two PON2 polymorphisms were significantly associated with AREase activity, and 37 polymorphisms with POase activity, however only nine were not in strong linkage disequilibrium (LD) with either PON1-108 or PON1192 (r2>0.20), SNPs with known effects on PON1 quantity and substrate-specific activity. Single tagSNPs PON155 and PON1192 accounted for similar ranges of AREase variation compared to haplotypes comprised of multiple SNPs within their haplotype blocks. However, PON155 explained 11-16% of POase activity, while six SNPs in the same haplotype block explained 3-fold more variance (36-56%). Although LD structure in the PON cluster seems similar between Mexicans and Caucasians, allele frequencies for many polymorphisms differed strikingly. Functional effects of PON genetic variation related to susceptibility to OPs and oxidative stress also differed by age, and should be considered in protecting vulnerable subpopulations. PMID:20839225

  6. A HapMap leads to a Capsicum annuum SNP infinium array: a new tool for pepper breeding

    PubMed Central

    Hulse-Kemp, Amanda M; Ashrafi, Hamid; Plieske, Joerg; Lemm, Jana; Stoffel, Kevin; Hill, Theresa; Luerssen, Hartmut; Pethiyagoda, Charit L; Lawley, Cindy T; Ganal, Martin W; Van Deynze, Allen

    2016-01-01

    The Capsicum genus (Pepper) is a part of the Solanacae family. It has been important in many cultures worldwide for its key nutritional components and uses as spices, medicines, ornamentals and vegetables. Worldwide population growth is associated with demand for more nutritionally valuable vegetables while contending with decreasing resources and available land. These conditions require increased efficiency in pepper breeding to deal with these imminent challenges. Through resequencing of inbred lines we have completed a valuable haplotype map (HapMap) for the pepper genome based on single-nucleotide polymorphisms (SNP). The identified SNPs were annotated and classified based on their gene annotation in the pepper draft genome sequence and phenotype of the sequenced inbred lines. A selection of one marker per gene model was utilized to create the PepperSNP16K array, which simultaneously genotyped 16 405 SNPs, of which 90.7% were found to be informative. A set of 84 inbred and hybrid lines and a mapping population of 90 interspecific F2 individuals were utilized to validate the array. Diversity analysis of the inbred lines shows a distinct separation of bell versus chile/hot pepper types and separates them into five distinct germplasm groups. The interspecific population created between Tabasco (C. frutescens chile type) and P4 (C. annuum blocky type) produced a linkage map with 5546 markers separated into 1361 bins on twelve 12 linkage groups representing 1392.3 cM. This publically available genotyping platform can be used to rapidly assess a large number of markers in a reproducible high-throughput manner for pepper. As a standardized tool for genetic analyses, the PepperSNP16K can be used worldwide to share findings and analyze QTLs for important traits leading to continued improvement of pepper for consumers. Data and information on the array are available through the Solanaceae Genomics Network. PMID:27602231

  7. A HapMap leads to a Capsicum annuum SNP infinium array: a new tool for pepper breeding.

    PubMed

    Hulse-Kemp, Amanda M; Ashrafi, Hamid; Plieske, Joerg; Lemm, Jana; Stoffel, Kevin; Hill, Theresa; Luerssen, Hartmut; Pethiyagoda, Charit L; Lawley, Cindy T; Ganal, Martin W; Van Deynze, Allen

    2016-01-01

    The Capsicum genus (Pepper) is a part of the Solanacae family. It has been important in many cultures worldwide for its key nutritional components and uses as spices, medicines, ornamentals and vegetables. Worldwide population growth is associated with demand for more nutritionally valuable vegetables while contending with decreasing resources and available land. These conditions require increased efficiency in pepper breeding to deal with these imminent challenges. Through resequencing of inbred lines we have completed a valuable haplotype map (HapMap) for the pepper genome based on single-nucleotide polymorphisms (SNP). The identified SNPs were annotated and classified based on their gene annotation in the pepper draft genome sequence and phenotype of the sequenced inbred lines. A selection of one marker per gene model was utilized to create the PepperSNP16K array, which simultaneously genotyped 16 405 SNPs, of which 90.7% were found to be informative. A set of 84 inbred and hybrid lines and a mapping population of 90 interspecific F2 individuals were utilized to validate the array. Diversity analysis of the inbred lines shows a distinct separation of bell versus chile/hot pepper types and separates them into five distinct germplasm groups. The interspecific population created between Tabasco (C. frutescens chile type) and P4 (C. annuum blocky type) produced a linkage map with 5546 markers separated into 1361 bins on twelve 12 linkage groups representing 1392.3 cM. This publically available genotyping platform can be used to rapid