Templated sequence insertion polymorphisms in the human genome
NASA Astrophysics Data System (ADS)
Onozawa, Masahiro; Aplan, Peter
2016-11-01
Templated Sequence Insertion Polymorphism (TSIP) is a recently described form of polymorphism recognized in the human genome, in which a sequence that is templated from a distant genomic region is inserted into the genome, seemingly at random. TSIPs can be grouped into two classes based on nucleotide sequence features at the insertion junctions; Class 1 TSIPs show features of insertions that are mediated via the LINE-1 ORF2 protein, including 1) target-site duplication (TSD), 2) polyadenylation 10-30 nucleotides downstream of a “cryptic” polyadenylation signal, and 3) preference for insertion at a 5’-TTTT/A-3’ sequence. In contrast, class 2 TSIPs show features consistent with repair of a DNA double-strand break via insertion of a DNA “patch” that is derived from a distant genomic region. Survey of a large number of normal human volunteers demonstrates that most individuals have 25-30 TSIPs, and that these TSIPs track with specific geographic regions. Similar to other forms of human polymorphism, we suspect that these TSIPs may be important for the generation of human diversity and genetic diseases.
ERIC Educational Resources Information Center
Elwess, Nancy L.; Duprey, Stephen L.; Harney, Lindesay A.; Langman, Jessie E.; Marino, Tara C.; Martinez, Carolina; McKeon, Lauren L.; Moss, Chantel I. E.; Myrie, Sasha S.; Taylor, Luke Ryan
2008-01-01
"Alu"-insertion polymorphisms were used by an undergraduate Bioinformatics class to study how these insertion sites could be the basis for an investigation in human population genetics. Based on the students' investigation, both allele and genotype "Alu" frequencies were determined for African-American and Japanese populations as well as a…
Kuhn, Alexandre; Ong, Yao Min; Quake, Stephen R; Burkholder, William F
2015-07-08
Like other structural variants, transposable element insertions can be highly polymorphic across individuals. Their functional impact, however, remains poorly understood. Current genome-wide approaches for genotyping insertion-site polymorphisms based on targeted or whole-genome sequencing remain very expensive and can lack accuracy, hence new large-scale genotyping methods are needed. We describe a high-throughput method for genotyping transposable element insertions and other types of structural variants that can be assayed by breakpoint PCR. The method relies on next-generation sequencing of multiplex, site-specific PCR amplification products and read count-based genotype calls. We show that this method is flexible, efficient (it does not require rounds of optimization), cost-effective and highly accurate. This method can benefit a wide range of applications from the routine genotyping of animal and plant populations to the functional study of structural variants in humans.
Landscape of Insertion Polymorphisms in the Human Genome
Onozawa, Masahiro; Goldberg, Liat; Aplan, Peter D.
2015-01-01
Nucleotide substitutions, small (<50 bp) insertions or deletions (indels), and large (>50 bp) deletions are well-known causes of genetic variation within the human genome. We recently reported a previously unrecognized form of polymorphic insertions, termed templated sequence insertion polymorphism (TSIP), in which the inserted sequence was templated from a distant genomic region, and was inserted in the genome through reverse transcription of an RNA intermediate. TSIPs can be grouped into two classes based on nucleotide sequence features at the insertion junctions; class 1 TSIPs show target site duplication, polyadenylation, and preference for insertion at a 5′-TTTT/A-3′ sequence, suggesting a LINE-1 based insertion mechanism, whereas class 2 TSIPs show features consistent with repair of a DNA double strand break by nonhomologous end joining. To gain a more complete picture of TSIPs throughout the human population, we evaluated whole-genome sequence from 52 individuals, and identified 171 TSIPs. Most individuals had 25–30 TSIPs, and common (present in >20% of individuals) TSIPs were found in individuals throughout the world, whereas rare TSIPs tended to cluster in specific geographic regions. The number of rare TSIPs was greater than the number of common TSIPs, suggesting that TSIP generation is an ongoing process. Intriguingly, mitochondrial sequences were a frequent template for class 2 insertions, used more commonly than any nuclear chromosome. Similar to single nucleotide polymorphisms and indels, we suspect that these TSIPs may be important for the generation of human diversity and genetic diseases, and can be useful in tracking historical migration of populations. PMID:25745018
Bei, Thalia; Tilkeridis, Constantinos; Garantziotis, Stavros; Boikos, Sosipatros A.; Kazakos, Konstantinos; Simopoulos, Constantinos; Stratakis, Constantine A.
2011-01-01
OBJECTIVE We recently reported the association of the Sp1 site polymorphism of the COL1A1 gene with lumbar disk disease (LDD). In the present study we searched for a different polymorphism of the COL1A1 gene (which is usually not in linkage disequilibrium with the Sp1 site) in subjects with LDD. DESIGN Blood was collected from 24 Greek army recruits, aged 29±7.6 years, with LDD, and 66 healthy men, aged 26±4.38 years, matched for body mass index (BMI) and age, with normal BMD and with no history of trauma or fractures, who served as controls. DNA was extracted and the COL1A1 gene was sequenced. Of the control subjects, 12 were army recruits and 54 were selected from the general population. RESULTS The four base-pair insertion polymorphism in the COL1A1 gene analyzed by polymerase chain reaction amplification of DNA produces two different fragments (alleles A1 and A2): 14 patients (58.3%) were homozygous for A2A2, versus 35 controls (53%), while 3 patients (12.5%) were A1A1, and 8 of the control subjects (12%) had this genotype. There were no statistically significant differences in the presence of the two alleles of this polymorphism between patients with LDD and control subjects. CONCLUSIONS A four base-pair insertion polymorphism of the COL1A1 gene is not associated with the presence of LDD in young males, unlike the Sp1 site polymorphism of the same gene. These data reinforce the association between LDD and the functional polymorphisms of the Sp1 site by showing that other polymorphic sites of the of the COL1A1 gene in the same population of patients are not linked to the disease. PMID:18694864
USDA-ARS?s Scientific Manuscript database
The PCR-based Escherichia coli O157 (O157) strain typing system, Polymorphic Amplified Typing Sequences (PATS), targets insertions-deletions (Indels) and single nucleotide polymorphisms (SNPs) at the XbaI and AvrII(BlnI) restriction enzyme sites, respectively, besides amplifying four known virulenc...
Insertion and deletion polymorphisms of the ancient AluS family in the human genome.
Kryatova, Maria S; Steranka, Jared P; Burns, Kathleen H; Payer, Lindsay M
2017-01-01
Polymorphic Alu elements account for 17% of structural variants in the human genome. The majority of these belong to the youngest AluY subfamilies, and most structural variant discovery efforts have focused on identifying Alu polymorphisms from these currently retrotranspositionally active subfamilies. In this report we analyze polymorphisms from the evolutionarily older AluS subfamily, whose peak activity was tens of millions of years ago. We annotate the AluS polymorphisms, assess their likely mechanism of origin, and evaluate their contribution to structural variation in the human genome. Of 52 previously reported polymorphic AluS elements ascertained for this study, 48 were confirmed to belong to the AluS subfamily using high stringency subfamily classification criteria. Of these, the majority (77%, 37/48) appear to be deletion polymorphisms. Two polymorphic AluS elements (4%) have features of non-classical Alu insertions and one polymorphic AluS element (2%) likely inserted by a mechanism involving internal priming. Seven AluS polymorphisms (15%) appear to have arisen by the classical target-primed reverse transcription (TPRT) retrotransposition mechanism. These seven TPRT products are 3' intact with 3' poly-A tails, and are flanked by target site duplications; L1 ORF2p endonuclease cleavage sites were also observed, providing additional evidence that these are L1 ORF2p endonuclease-mediated TPRT insertions. Further sequence analysis showed strong conservation of both the RNA polymerase III promoter and SRP9/14 binding sites, important for mediating transcription and interaction with retrotransposition machinery, respectively. This conservation of functional features implies that some of these are fairly recent insertions since they have not diverged significantly from their respective retrotranspositionally competent source elements. Of the polymorphic AluS elements evaluated in this report, 15% (7/48) have features consistent with TPRT-mediated insertion, thus suggesting that some AluS elements have been more active recently than previously thought, or that fixation of AluS insertion alleles remains incomplete. These data expand the potential significance of polymorphic AluS elements in contributing to structural variation in the human genome. Future discovery efforts focusing on polymorphic AluS elements are likely to identify more such polymorphisms, and approaches tailored to identify deletion alleles may be warranted.
Galindo-González, Leonardo; Mhiri, Corinne; Grandbastien, Marie-Angèle; Deyholos, Michael K
2016-12-07
Initial characterization of the flax genome showed that Ty1-copia retrotransposons are abundant, with several members being recently inserted, and in close association with genes. Recent insertions indicate a potential for ongoing transpositional activity that can create genomic diversity among accessions, cultivars or varieties. The polymorphisms generated constitute a good source of molecular markers that may be associated with phenotype if the insertions alter gene activity. Flax, where accessions are bred mainly for seed nutritional properties or for fibers, constitutes a good model for studying the relationship of transpositional activity with diversification and breeding. In this study, we estimated copy number and used a type of transposon display known as Sequence-Specific Amplification Polymorphisms (SSAPs), to characterize six families of Ty1-copia elements across 14 flax accessions. Polymorphic insertion sites were sequenced to find insertions that could potentially alter gene expression, and a preliminary test was performed with selected genes bearing transposable element (TE) insertions. Quantification of six families of Ty1-copia elements indicated different abundances among TE families and between flax accessions, which suggested diverse transpositional histories. SSAPs showed a high level of polymorphism in most of the evaluated retrotransposon families, with a trend towards higher levels of polymorphism in low-copy number families. Ty1-copia insertion polymorphisms among cultivars allowed a general distinction between oil and fiber types, and between spring and winter types, demonstrating their utility in diversity studies. Characterization of polymorphic insertions revealed an overwhelming association with genes, with insertions disrupting exons, introns or within 1 kb of coding regions. A preliminary test on the potential transcriptional disruption by TEs of four selected genes evaluated in three different tissues, showed one case of significant impact of the insertion on gene expression. We demonstrated that specific Ty1-copia families have been active since breeding commenced in flax. The retrotransposon-derived polymorphism can be used to separate flax types, and the close association of many insertions with genes defines a good source of potential mutations that could be associated with phenotypic changes, resulting in diversification processes.
Li, Chun-Xiao; Jiang, Mei-Shan; Chen, Shi-Yi; Lai, Song-Jia
2008-07-01
Single nucleotide polymorphism (SNP) in exon 1 and 3 of fibroblast growth factor (FGF5) gene was studied by DNA sequencing in Yingjing angora rabbit, Tianfu black rabbit and California rabbit. A frameshift mutation (TCT insert) at base position 217 (site A) of exon 1 and a T/C missense mutation at base position 59 (site B) of exon 3 were found in Yingjing angora rabbit with a high frequency; a T/C same-sense mutation at base position 3 (site C) of exon 3 was found with similar frequency in three rabbit breeds. Least square analysis showed that different genotypes had no significant association with wool yield in site A, and had high significant association with wool yield in site B (P<0.01) and significant association with wool yield in site C (P<0.05). It was concluded from the results that FGF5 gene could be the potential major gene affecting wool yield or link with the major gene, and polymorphic loci B and C may be used as molecular markers for im-proving wool yield in angora rabbits.
Human Alu insertion polymorphisms in North African populations.
Cherni, Loth; Frigi, Sabeh; Ennafaa, Hajer; Mtiraoui, Nabil; Mahjoub, Touhami; Benammar-Elgaaied, Amel
2011-10-01
Several features make Alu insertions a powerful tool used in population genetic studies: the polymorphic nature of many Alu insertions, the stability of an Alu insertion event and, furthermore, the ancestral state of an Alu insertion is known to be the absence of the Alu element at a particular locus and the presence of an Alu insertion at the site that forward mutational change. This study analyses seven Alu insertion polymorphisms in a sample of 297 individuals from the autochthonous population of Tunisia (Thala, Smar, Zarzis, and Bou Salem) and Libya with the aim of studying their genetic structure with respect to the populations of North Africa, Western, Eastern and Central Europe. The comparative analyses carried out using the MDS and AMOVA methods reveal the existence of spatial heterogeneity, and identify four population groups. Study populations (Libya, Smar, Zarzis, and Bou Salem) are closest to North African populations whereas Thala is isolated and is closest to Western European populations. In conclusion, Results of the present study support the important role that migratory movements have played in the North African gene pool, at least since the Neolithic period.
Genetic diversity and classification of Tibetan yak populations based on the mtDNA COIII gene.
Song, Q Q; Chai, Z X; Xin, J W; Zhao, S J; Ji, Q M; Zhang, C F; Ma, Z J; Zhong, J C
2015-03-13
To determine the level of genetic diversity and phylogenetic relationships among Tibetan yak populations, the mitochondrial DNA cytochrome c oxidase subunit 3 (COIII) genes of 378 yak individuals from 16 populations were analyzed in this study. The results showed that the length of cytochrome c oxidase subunit 3 gene sequences was 781 bp, with nucleotide frequencies of 29.2, 29.4, 26.1, and 15.2% for T, C, A, and G, respectively. A total of 26 haplotypes were identified, with 69 polymorphic sites, including 11 parsimony-informative sites and 58 single-nucleotide polymorphism sites. No deletions/insertions were found in sequence comparison, indicating that nucleotide mutation types were transitions and transversions. Haplotype and nucleotide diversities were 0.562 and 0.00138, respectively, indicating a high level of genetic diversity in Tibetan yak populations. Phylogenetic relationship analysis indicated that Tibetan yak populations are divided into 2 groups.
Macé, Matthias; Crouau-Roy, Brigitte
2008-01-01
Background The early radiation of the Cetartiodactyla is complex, and unambiguous molecular characters are needed to clarify the positions of hippotamuses, camels and pigs relative to the remaining taxa (Cetacea and Ruminantia). There is also a need for informative genealogic markers for Y-chromosome population genetics as well as a sexing method applicable to all species from this group. We therefore studied the sequence variation of a partial sequence of the evolutionary conserved amelogenin gene to assess its potential use in each of these fields. Results and discussion We report a large interstitial insertion in the Y amelogenin locus in most of the Cetartiodactyla lineages (cetaceans and ruminants). This sex-linked size polymorphism is the result of a 460–465 bp inserted element in intron 4 of the amelogenin gene of Ruminants and Cetaceans. Therefore, this polymorphism can easily be used in a sexing assay for these species. When taking into account this shared character in addition to nucleotide sequence, gene genealogy follows sex-chromosome divergence in Cetartiodactyla whereas it is more congruent with zoological history when ignoring these characters. This could be related to a loss of homology between chromosomal copies given the old age of the insertion. The 1 kbp Amel-Y amplified fragment is also characterized by high nucleotide diversity (64 polymorphic sites spanning over 1 kbp in seven haplotypes) which is greater than for other Y-chromosome sequence markers studied so far but less than the mitochondrial control region. Conclusion The gender-dependent polymorphism we have identified is relevant not only for phylogenic inference within the Cetartiodactyla but also for Y-chromosome based population genetics and gender determination in cetaceans and ruminants. One single protocol can therefore be used for studies in population and evolutionary genetics, reproductive biotechnologies, and forensic science. PMID:18925953
The Geographic Distribution of Human Y Chromosome Variation
Hammer, M. F.; Spurdle, A. B.; Karafet, T.; Bonner, M. R.; Wood, E. T.; Novelletto, A.; Malaspina, P.; Mitchell, R. J.; Horai, S.; Jenkins, T.; Zegura, S. L.
1997-01-01
We examined variation on the nonrecombining portion of the human Y chromosome to investigate human evolution during the last 200,000 years. The Y-specific polymorphic sites included the Y Alu insertional polymorphism or ``YAP'' element (DYS287), the poly(A) tail associated with the YAP element, three point mutations in close association with the YAP insertion site, an A-G polymorphic transition (DYS271), and a tetranucleotide microsatellite (DYS19). Global variation at the five bi-allelic sites (DYS271, DYS287, and the three point mutations) gave rise to five ``YAP haplotypes'' in 60 populations from Africa, Europe, Asia, Australasia, and the New World (n = 1500). Combining the multi-allelic variation at the microsatellite loci (poly(A) tail and DYS19) with the YAP haplotypes resulted in a total of 27 ``combination haplotypes''. All five of the YAP haplotypes and 21 of the 27 combination haplotypes were found in African populations, which had greater haplotype diversity than did populations from other geographical locations. Only subsets of the five YAP haplotypes were found outside of Africa. Patterns of observed variation were compatible with a variety of hypotheses, including multiple human migrations and range expansions. PMID:9055088
Dall'Olio, Stefania; Scotti, Emilio; Fontanesi, Luca; Tassinari, Marco
2014-01-01
The myostatin (MSTN) gene encodes a protein known to be a negative regulator of muscle mass in mammalian species. Different polymorphisms of the horse (Equus caballus) MSTN gene have been identified, including single nucleotide polymorphisms and a short interspersed nuclear element (SINE) insertion of 227 bp within the promoter of the gene. The SINE insertion has been associated with performance traits in Thoroughbred racehorses and it was proposed as a predictor of optimum racing distance. The aims of this study were to perform in silico analysis to identify putative gains or abrogation of transcription-factor binding sites (TFBSs) generated by the SINE allele of the promoter and to analyse the frequency of the SINE insertion in horses used for racing (gallop and trot) and other purposes. The SINE insertion was genotyped in 227 horses from 10 breeds belonging to different morphological types (brachimorphic, mesomorphic, meso-dolichomorphic and dolichomorphic). The presence of the insertion was confirmed in the Quarter Horse (SINE allele frequency of 0.81) and in the Thoroughbred (0.51), whereas the SINE allele did not segregate in any of the other analysed breeds. As the SINE MSTN gene polymorphism may be population or breed specific, it is not a useful marker for association studies in all breeds.
Population and clinical genetics of human transposable elements in the (post) genomic era
Rishishwar, Lavanya; Wang, Lu; Clayton, Evan A.; Mariño-Ramírez, Leonardo; McDonald, John F.; Jordan, I. King
2017-01-01
ABSTRACT Recent technological developments—in genomics, bioinformatics and high-throughput experimental techniques—are providing opportunities to study ongoing human transposable element (TE) activity at an unprecedented level of detail. It is now possible to characterize genome-wide collections of TE insertion sites for multiple human individuals, within and between populations, and for a variety of tissue types. Comparison of TE insertion site profiles between individuals captures the germline activity of TEs and reveals insertion site variants that segregate as polymorphisms among human populations, whereas comparison among tissue types ascertains somatic TE activity that generates cellular heterogeneity. In this review, we provide an overview of these new technologies and explore their implications for population and clinical genetic studies of human TEs. We cover both recent published results on human TE insertion activity as well as the prospects for future TE studies related to human evolution and health. PMID:28228978
Schiavo, Giuseppina; Hoffmann, Orsolya Ivett; Ribani, Anisa; Utzeri, Valerio Joe; Ghionda, Marco Ciro; Bertolini, Francesca; Geraci, Claudia; Bovo, Samuele; Fontanesi, Luca
2017-10-01
Nuclear DNA sequences of mitochondrial origin (numts) are derived by insertion of mitochondrial DNA (mtDNA), into the nuclear genome. In this study, we provide, for the first time, a genome picture of numts inserted in the pig nuclear genome. The Sus scrofa reference nuclear genome (Sscrofa10.2) was aligned with circularized and consensus mtDNA sequences using LAST software. A total of 430 numt sequences that may represent 246 different numt integration events (57 numt regions determined by at least two numt sequences and 189 singletons) were identified, covering about 0.0078% of the nuclear genome. Numt integration events were correlated (0.99) to the chromosome length. The longest numt sequence (about 11 kbp) was located on SSC2. Six numts were sequenced and PCR amplified in pigs of European commercial and local pig breeds, of the Chinese Meishan breed and in European wild boars. Three of them were polymorphic for the presence or absence of the insertion. Surprisingly, the estimated age of insertion of two of the three polymorphic numts was more ancient than that of the speciation time of the Sus scrofa, supporting that these polymorphic sites were originated from interspecies admixture that contributed to shape the pig genome. © The Author 2017. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.
Wang, NaNa; Chen, KeYu; Xu, Jia; Yuan, Fang; Li, HongYu; Deng, FengMei; Zhang, LuShun
2018-01-01
Evidence from recent researchers suggested that RTN4 is a multifunctional gene, including tumor suppression, apoptosis, vascular remodeling, and inhibition of axonal regeneration. The CAA and TATC insertion/deletion polymorphisms (CAA/TATC polymorphisms) of RTN4 3″-untranslated regions (UTRs) have been linked to cervical squamous cell carcinoma (CSCC), uterine leiomyomas (UL) and non-small cell lung cancer (NSCLC). However, the association between these two polymorphisms sites with Hepatocellular Carcinoma (HCC) risk was not carry out before. A total of 284 HCC patients and 484 control subjects were recruited for this study. The RTN4 CAA/TATC insertion/deletion genotypes were determined using polymerase chain reaction (PCR) assay. The ID/DD genotypes of CAA were significantly associated with an increased risk of HCC compared with the II genotype (ID vs. II: OR = 1.50, 95% CI: 1.10-2.04; DD vs. II: OR = 2.00, 95%CI: 1.15-3.46). Meanwhile, the frequency of D allele of CAA was significantly related with an increased risk of HCC compared with the I allele (D vs. I: OR = 1.39, 95% CI: 1.12-1.73). The ID genotypes of TATC was significantly associated with an increased risk of HCC compared with the DD genotype (ID vs. DD: OR = 1.70, 95% CI: 1.23-2.33). The present study provided evidence that RTN4 CAA/TATC polymorphisms were associated with HCC development in Chinese Han population.
Assessment of Azorean ancestry by Alu insertion polymorphisms.
Branco, Claudia C; Palla, Raquel; Lino, Sílvia; Pacheco, Paula R; Cabral, Rita; De Fez, Laura; Peixoto, Bernardo R; Mota-Vieira, Luisa
2006-01-01
Knowledge of population ancestry from genetic markers is essential, for example, to understand the history of human migration and to carry out admixture and association studies. Here we assess the genome ancestry of the Azorean population through analysis of six Alu polymorphic sites (TPA-25, ACE, APO, B65, PV92, and D1) in 65 Azoreans and 30 Portuguese unrelated blood donors and compare data for the Y-chromosome and mtDNA. Allele frequencies were calculated by direct counting. Statistical analysis was performed using Arlequin 2.0. Nei's genetic distance was calculated with DISPAN software, and trees were constructed by neighbor joining (NJ) using PHYLIP 3.63. The results show that all Alu insertions were polymorphic. APO is the closest to fixation. The less frequent insertions are PV92 and D1 in the Azores and Portugal, respectively. ACE and TPA-25 show the highest values of heterozygosity in both populations. Allele frequencies are very similar to those obtained in European populations. These results are validated by the Y-chromosome and mtDNA data, where the majority of the maternal and paternal lineages are European. Overall, these data are reflected in the phylogenetic tree, in which the Azoreans and the Portuguese branch with Catalans, Andalusians, Moroccans, and Algerians. We conclude that the population of the Azores shows no significant genetic differences from that of mainland Portugal and that it is an outbred population. Moreover, the data validate the use of Alu insertion polymorphisms to assess the origin and history of human populations. Am. J. Hum. Biol. 18:223-226, 2006. (c) 2006 Wiley-Liss, Inc.
Onozawa, Masahiro; Zhang, Zhenhua; Kim, Yoo Jung; Goldberg, Liat; Varga, Tamas; Bergsagel, P Leif; Kuehl, W Michael; Aplan, Peter D
2014-05-27
We used the I-SceI endonuclease to produce DNA double-strand breaks (DSBs) and observed that a fraction of these DSBs were repaired by insertion of sequences, which we termed "templated sequence insertions" (TSIs), derived from distant regions of the genome. These TSIs were derived from genic, retrotransposon, or telomere sequences and were not deleted from the donor site in the genome, leading to the hypothesis that they were derived from reverse-transcribed RNA. Cotransfection of RNA and an I-SceI expression vector demonstrated insertion of RNA-derived sequences at the DNA-DSB site, and TSIs were suppressed by reverse-transcriptase inhibitors. Both observations support the hypothesis that TSIs were derived from RNA templates. In addition, similar insertions were detected at sites of DNA DSBs induced by transcription activator-like effector nuclease proteins. Whole-genome sequencing of myeloma cell lines revealed additional TSIs, demonstrating that repair of DNA DSBs via insertion was not restricted to experimentally produced DNA DSBs. Analysis of publicly available databases revealed that many of these TSIs are polymorphic in the human genome. Taken together, these results indicate that insertional events should be considered as alternatives to gross chromosomal rearrangements in the interpretation of whole-genome sequence data and that this mutagenic form of DNA repair may play a role in genetic disease, exon shuffling, and mammalian evolution.
Boas, Wendell Vilas; Gonçalves, Rozana Oliveira; Costa, Olívia Lúcia Nunes; Goncalves, Marilda Souza
2015-02-01
To investigate the association between polymorphisms in genes that encode enzymes involved in folate- and vitamin B12-dependent homocysteine metabolism and recurrent spontaneous abortion (RSA). We investigated the C677T and A1298C polymorphisms of the methylenetetrahydrofalate reductase gene (MTHFR), the A2756G polymorphism of the methionine synthase gene (MS) and the 844ins68 insertion of the cystathionine beta synthetase gene (CBS). The PCR technique followed by RFLP was used to assess the polymorphisms; the serum levels of homocysteine, vitamin B12 and folate were investigated by chemiluminescence. The EPI Info Software version 6.04 was used for statistical analysis. Parametric variables were compared by Student's t-test and nonparametric variables by the Wilcoxon rank sum test. The frequencies of gene polymorphisms in 89 women with a history of idiopathic recurrent miscarriage and 150 controls were 19.1 and 19.6% for the C677T, insertion, 20.8 and 26% for the A1298C insertion, 14.2 and 21.9% for the A2756G insertion, and 16.4 and 18% for the 844ins68 insertion, respectively. There were no significant differences between case and control groups in any of the gene polymorphisms investigated. However, the frequency of the 844ins68 insertion in the CBS gene was higher among women with a history of loss during the third trimester of pregnancy (p=0.003). Serum homocysteine, vitamin B12 and folate levels id not differ between the polymorphisms studied in the case and control groups. However, linear regression analysis showed a dependence of serum folate levels on the maintenance of tHcy levels. The investigated gene polymorphisms and serum homocysteine, vitamin B12 and folate levels were not associated with idiopathic recurrent miscarriage in the present study. Further investigations are needed in order to confirm the role of the CBS 844ins68 insertion in recurrent miscarriage.
Arman, Ahmet; Ozon, Alev; Isguven, Pinar S; Coker, Ajda; Peker, Ismail; Yordam, Nursen
2008-01-01
Growth hormone (GH) is involved in growth, and fat and carbohydrate metabolism. Interaction of GH with the GH receptor (GHR) is necessary for systemic and local production of insulin-like growth factor-I (IGF-I) which mediates GH actions. Mutations in the GHR cause severe postnatal growth failure; the disorder is an autosomal recessive genetic disease resulting in GH insensitivity, called Laron syndrome. It is characterized by dwarfism with elevated serum GH and low levels of IGF-I. We analyzed the GHR gene for mutations and polymorphisms in eight patients with Laron-type dwarfism from six families. We found three missense mutations (S40L, V125A, I526L), one nonsense mutation (W157X), and one splice site mutation in the extracellular domain of GHR. Furthermore, G168G and exon 3 deletion polymorphisms were detected in patients with Laron syndrome. The splice site mutation, which is a novel mutation, was located at the donor splice site of exon 2/ intron 2 within GHR. Although this mutation changed the highly conserved donor splice site consensus sequence GT to GGT by insertion of a G residue, the intron splicing between exon 2 and exon 3 was detected in the patient. These results imply that the splicing occurs arthe GT site in intron 2, leaving the extra inserted G residue at the end of exon 2, thus changing the open reading frame of GHR resulting in a premature termination codon in exon 3.
UCHIDA, Leo; HERIYANTO, Agus; THONGCHAI, Chalermchaikit; HANH, Tran Thi; HORIUCHI, Motohiro; ISHIHARA, Kanako; TAMURA, Yutaka; MURAMATSU, Yasukazu
2014-01-01
ABSTRACT There has been an accumulation of information on frequencies of insertion/deletion (indel) polymorphisms within the bovine prion protein gene (PRNP) and on the number of octapeptide repeats and single nucleotide polymorphisms (SNPs) in the coding region of bovine PRNP related to bovine spongiform encephalopathy (BSE) susceptibility. We investigated the frequencies of 23-bp indel polymorphism in the promoter region (23indel) and 12-bp indel polymorphism in intron 1 region (12indel), octapeptide repeat polymorphisms and SNPs in the bovine PRNP of cattle and water buffaloes in Vietnam, Indonesia and Thailand. The frequency of the deletion allele in the 23indel site was significantly low in cattle of Indonesia and Thailand and water buffaloes. The deletion allele frequency in the 12indel site was significantly low in all of the cattle and buffaloes categorized in each subgroup. In both indel sites, the deletion allele has been reported to be associated with susceptibility to classical BSE. In some Indonesian local cattle breeds, the frequency of the allele with 5 octapeptide repeats was significantly high despite the fact that the allele with 6 octapeptide repeats has been reported to be most frequent in many breeds of cattle. Four SNPs observed in Indonesian local cattle have not been reported for domestic cattle. This study provided information on PRNP of livestock in these Southeast Asian countries. PMID:24705506
Rajasekaran, M.; Abirami, Santhanam; Chen, Chinpan
2011-01-01
Background Arylamine N-acetyltransferase 2 (NAT2) is an important catalytic enzyme that metabolizes the carcinogenic arylamines, hydrazine drugs and chemicals. This enzyme is highly polymorphic in different human populations. Several polymorphisms of NAT2, including the single amino acid substitutions R64Q, I114T, D122N, L137F, Q145P, R197Q, and G286E, are classified as slow acetylators, whereas the wild-type NAT2 is classified as a fast acetylator. The slow acetylators are often associated with drug toxicity and efficacy as well as cancer susceptibility. The biological functions of these 7 mutations have previously been characterized, but the structural basis behind the reduced catalytic activity and reduced protein level is not clear. Methodology/Principal Findings We performed multiple molecular dynamics simulations of these mutants as well as NAT2 to investigate the structural and dynamical effects throughout the protein structure, specifically the catalytic triad, cofactor binding site, and the substrate binding pocket. None of these mutations induced unfolding; instead, their effects were confined to the inter-domain, domain 3 and 17-residue insert region, where the flexibility was significantly reduced relative to the wild-type. Structural effects of these mutations propagate through space and cause a change in catalytic triad conformation, cofactor binding site, substrate binding pocket size/shape and electrostatic potential. Conclusions/Significance Our results showed that the dynamical properties of all the mutant structures, especially in inter-domain, domain 3 and 17-residue insert region were affected in the same manner. Similarly, the electrostatic potential of all the mutants were altered and also the functionally important regions such as catalytic triad, cofactor binding site, and substrate binding pocket adopted different orientation and/or conformation relative to the wild-type that may affect the functions of the mutants. Overall, our study may provide the structural basis for reduced catalytic activity and protein level, as was experimentally observed for these polymorphisms. PMID:21980537
Khan, Imran A; Jahan, Parveen; Hasan, Qurratulain; Rao, Pragna
2014-12-01
Gestational diabetes mellitus (GDM) is defined as glucose intolerance first recognized during pregnancy. Insertion/deletion (I/D) polymorphism of a 287 bp Alu repetitive sequence in intron 16 of the angiotensin-converting enzyme (ACE) gene has been widely investigated in Asian Indian populations with different ethnic origins. The present study examined possible association between I/D polymorphism of the ACE gene and GDM in Asian Indian pregnant women. A total of 200 pregnant women (100 GDM and 100 non-GDM) were recruited in this study and I/D polymorphism of a 287 bp Alu1 element inside intron 16 of the ACE gene was examined by polymerase chain reaction (PCR)-based gel electrophoresis. The distribution of the variants like II, ID, and DD genotypes of ACE gene showed differences between normal GDM versus non-GDM subjects, and the frequency of the ID+ DD Vs II genotype was significant (p=0.0002) in the GDM group. ACE gene polymorphism was associated with GDM in Asian Indian pregnant women. © The Author(s) 2013.
Evolutionary genomics of miniature inverted-repeat transposable elements (MITEs) in Brassica.
Nouroz, Faisal; Noreen, Shumaila; Heslop-Harrison, J S
2015-12-01
Miniature inverted-repeat transposable elements (MITEs) are truncated derivatives of autonomous DNA transposons, and are dispersed abundantly in most eukaryotic genomes. We aimed to characterize various MITEs families in Brassica in terms of their presence, sequence characteristics and evolutionary activity. Dot plot analyses involving comparison of homoeologous bacterial artificial chromosome (BAC) sequences allowed identification of 15 novel families of mobile MITEs. Of which, 5 were Stowaway-like with TA Target Site Duplications (TSDs), 4 Tourist-like with TAA/TTA TSDs, 5 Mutator-like with 9-10 bp TSDs and 1 novel MITE (BoXMITE1) flanked by 3 bp TSDs. Our data suggested that there are about 30,000 MITE-related sequences in Brassica rapa and B. oleracea genomes. In situ hybridization showed one abundant family was dispersed in the A-genome, while another was located near 45S rDNA sites. PCR analysis using primers flanking sequences of MITE elements detected MITE insertion polymorphisms between and within the three Brassica (AA, BB, CC) genomes, with many insertions being specific to single genomes and others showing evidence of more recent evolutionary insertions. Our BAC sequence comparison strategy enables identification of evolutionarily active MITEs with no prior knowledge of MITE sequences. The details of MITE families reported in Brassica enable their identification, characterization and annotation. Insertion polymorphisms of MITEs and their transposition activity indicated important mechanism of genome evolution and diversification. MITE families derived from known Mariner, Harbinger and Mutator DNA transposons were discovered, as well as some novel structures. The identification of Brassica MITEs will have broad applications in Brassica genomics, breeding, hybridization and phylogeny through their use as DNA markers.
Kuhn, Alexandre; Ong, Yao Min; Cheng, Ching-Yu; Wong, Tien Yin; Quake, Stephen R; Burkholder, William F
2014-06-03
Insertions of the human-specific subfamily of LINE-1 (L1) retrotransposon are highly polymorphic across individuals and can critically influence the human transcriptome. We hypothesized that L1 insertions could represent genetic variants determining important human phenotypic traits, and performed an integrated analysis of L1 elements and single nucleotide polymorphisms (SNPs) in several human populations. We found that a large fraction of L1s were in high linkage disequilibrium with their surrounding genomic regions and that they were well tagged by SNPs. However, L1 variants were only partially captured by SNPs on standard SNP arrays, so that their potential phenotypic impact would be frequently missed by SNP array-based genome-wide association studies. We next identified potential phenotypic effects of L1s by looking for signatures of natural selection linked to L1 insertions; significant extended haplotype homozygosity was detected around several L1 insertions. This finding suggests that some of these L1 insertions may have been the target of recent positive selection.
Zhao, Huanqiang; Hu, Fupin; Jin, Shu; Xu, Xiaogang; Zou, Yuhan; Ding, Baixing; He, Chunyan; Gong, Fang; Liu, Qingzhong
2016-01-01
Panton-Valentine leukocidin (PVL, encoded by lukSF-PV genes), a bi-component and pore-forming toxin, is carried by different staphylococcal bacteriophages. The prevalence of PVL in Staphylococcus aureus has been reported around the globe. However, the data on PVL-encoding phage types, lukSF-PV gene variation and chromosomal phage insertion sites for PVL-positive S. aureus are limited, especially in China. In order to obtain a more complete understanding of the molecular epidemiology of PVL-positive S. aureus, an integrated and modified PCR-based scheme was applied to detect the PVL-encoding phage types. Phage insertion locus and the lukSF-PV variant were determined by PCR and sequencing. Meanwhile, the genetic background was characterized by staphylococcal cassette chromosome mec (SCCmec) typing, staphylococcal protein A (spa) gene polymorphisms typing, pulsed-field gel electrophoresis (PFGE) typing, accessory gene regulator (agr) locus typing and multilocus sequence typing (MLST). Seventy eight (78/1175, 6.6%) isolates possessed the lukSF-PV genes and 59.0% (46/78) of PVL-positive strains belonged to CC59 lineage. Eight known different PVL-encoding phage types were detected, and Φ7247PVL/ΦST5967PVL (n = 13) and ΦPVL (n = 12) were the most prevalent among them. While 25 (25/78, 32.1%) isolates, belonging to ST30, and ST59 clones, were unable to be typed by the modified PCR-based scheme. Single nucleotide polymorphisms (SNPs) were identified at five locations in the lukSF-PV genes, two of which were non-synonymous. Maximum-likelihood tree analysis of attachment sites sequences detected six SNP profiles for attR and eight for attL, respectively. In conclusion, the PVL-positive S. aureus mainly harbored Φ7247PVL/ΦST5967PVL and ΦPVL in the regions studied. lukSF-PV gene sequences, PVL-encoding phages, and phage insertion locus generally varied with lineages. Moreover, PVL-positive clones that have emerged worldwide likely carry distinct phages.
Mohammadi, Nabiallah; Adib, Minoo; Alsahebfosoul, Fereshteh; Kazemi, Mohammad; Etemadifar, Masoud
2016-01-15
Human Leukocyte Antigen G (HLA-G) gene polymorphism and expression rate have recently been suggested to have a potential role in susceptibility to Multiple Sclerosis (MS), a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system with unknown etiology. The aim of this study was to investigate the association of the frequency of HLA-G gene 14 bp insertion/deletion polymorphism and its plasma level with MS susceptibility. In this study, the HLA-G gene from 212 patients and 210 healthy individuals was amplified using real time PCR and screened for the 14 bp insertion/deletion polymorphism. In addition, HLA-G plasma levels of the patients were measured and compared to normal controls by ELISA method. Our results revealed that 14 bp insertion in HLA-G could result in lower plasma HLA-G level of the subjects, regardless of their health status and vice versa. Additionally, significant correlation of HLA-G genotype and its plasma level with MS susceptibility was observed. In conclusion, not only HLA-G 14 bp insertion/deletion polymorphism could be associated with expression rate of the HLA-G gene and its plasma level, but also could be considered as a risk factor for susceptibility to MS in our study population. Copyright © 2015 Elsevier B.V. All rights reserved.
Saracevic, Andrea; Simundic, Ana-Maria; Celap, Ivana; Luzanic, Valentina
2013-07-01
Rigat and colleagues were the first ones to develop a rapid PCR-based assay for identifying the angiotensin converting enzyme insertion/deletion (I/D) polymorphism. Due to a big difference between the length of the wild-type and mute alleles the PCR method is prone to mistyping because of preferential amplification of the D allele causing depicting I/D heterozygotes as D/D homozygotes. The aim of this study was to investigate whether this preferential amplification can be repressed by amplifying a longer DNA fragment in a so called Long PCR protocol. We also aimed to compare the results of genotyping using five different PCR protocols and to estimate the mistyping rate. The study included 200 samples which were genotyped using standard method used in our laboratory, a stepdown PCR, PCR protocol with the inclusion of 4 % DMSO, PCR with the use of insertion specific primers and new Long PCR method. The results of this study have shown that accurate ACE I/D polymorphism genotyping can be accomplished with the standard and the Long PCR method. Also, as of our results, accurate ACE I/D polymorphism genotyping can be accomplished regardless of the method used. Therefore, if the standard method is optimized more cautiously, accurate results can be obtained by this simple, inexpensive and rapid PCR protocol.
[Observation on gene polymorphism of Rh blood group in Chinese Han nationality].
Lan, Jiong-Cai; Wang, Cong-Rong; Wei, Ya-Ming; Zhou, Hua-You; Cao, Qiong; Zhang, Yin-Ze; Jiang, KuReXi; Wu, Da-Lin; Liu, Zhong
2003-12-01
To observe the gene polymorphism of Rh blood group in unrelated random individuals and families for Chinese Han nationality, polymerase chain reaction-sequence specific primer (PCR-SSP) was used to amplify the Rh C/E gene, RhD gene, exons, intron 2 and 10, insert and Rh Box in 160 blood samples of RhD positive unrelated individuals and 71 samples of RhD negative unrelated individuals and 7 samples of families whose probands were RhD-negative. The results showed that RhD genes of RhD-negative individuals with C antigens were polymorphism, three forms were found for D exon including intact, partial deletion and complete deletion exons. Insert fragments and Rh Box were found in most cases of families whose probands were RhD-negative and its inheritance accorded with the Mendel's Law, and it did not affect the expression of RhD gene. "Normal" RhD exon 4 amplifying product was not found in all of the samples. It was concluded that gene structure of the RhD-negative in Chinese was polymorphism, intact, partial deletion and complete deletion exons were found in the individuals with C antigen and probably existed specific D (nf) Ce haplotype. The function of insert was uncertain. The Rh gene sequences of Chinese Han nationality are different from those of Caucasian and the Rh gene library based on Han nationality should be established.
Han, Mengxue; Sun, Qibao; Zhou, Junyong; Qiu, Huarong; Guo, Jing; Lu, Lijuan; Mu, Wenlei; Sun, Jun
2017-09-01
Insertion of a solo LTR, which possesses strong bidirectional, stem-specific promoter activities, is associated with the evolution of a dwarfing apple spur mutation. Spur mutations in apple scions revolutionized global apple production. Since long terminal repeat (LTR) retrotransposons are tightly related to natural mutations, inter-retrotransposon-amplified polymorphism technique and genome walking were used to find sequences in the apple genome based on these LTRs. In 'Red Delicious' spur mutants, a novel, 2190-bp insertion was identified as a spur-specific, solo LTR (sLTR) located at the 1038th nucleotide of another sLTR, which was 1536 bp in length. This insertion-within-an-insertion was localized within a preexisting Gypsy-50 retrotransposon at position 3,762,767 on chromosome 4. The analysis of transcriptional activity of the two sLTRs (the 2190- and 1536-bp inserts) indicated that the 2190-bp sLTR is a promoter, capable of bidirectional transcription. GUS expression in the 2190-bp-sense and 2190-bp-antisense transgenic lines was prominent in stems. In contrast, no promoter activity from either the sense or the antisense strand of the 1536-bp sLTR was detected. From ~150 kb of DNA on each side of the 2190 bp, sLTR insertion site, corresponding to 300 kb of the 'Golden Delicious' genome, 23 genes were predicted. Ten genes had predicted functions that could affect shoot development. This first report, of a sLTR insertion associated with the evolution of apple spur mutation, will facilitate apple breeding, cloning of spur-related genes, and discovery of mechanisms behind dwarf habit.
2012-01-01
Background Rapeseed (Brassica napus L.) has spring and winter genotypes adapted to different growing seasons. Winter genotypes do not flower before the onset of winter, thus leading to a longer vegetative growth period that promotes the accumulation and allocation of more resources to seed production. The development of winter genotypes enabled the rapeseed to spread rapidly from southern to northern Europe and other temperate regions of the world. The molecular basis underlying the evolutionary transition from spring- to winter- type rapeseed is not known, however, and needs to be elucidated. Results We fine-mapped the spring environment specific quantitative trait locus (QTL) for flowering time, qFT10-4,in a doubled haploid (DH) mapping population of rapeseed derived from a cross between Tapidor (winter-type) and Ningyou7 (semi-winter) and delimited the qFT10-4 to an 80-kb region on chromosome A10 of B. napus. The BnFLC.A10 gene, an ortholog of FLOWERING LOCUS C (FLC) in Arabidopsis, was cloned from the QTL. We identified 12 polymorphic sites between BnFLC.A10 parental alleles of the TN-DH population in the upstream region and in intron 1. Expression of both BnFLC.A10 alleles decreased during vernalization, but decreased more slowly in the winter parent Tapidor. Haplotyping and association analysis showed that one of the polymorphic sites upstream of BnFLC.A10 is strongly associated with the vernalization requirement of rapeseed (r2 = 0.93, χ2 = 0.50). This polymorphic site is derived from a Tourist-like miniature inverted-repeat transposable element (MITE) insertion/deletion in the upstream region of BnFLC.A10. The MITE sequence was not present in the BnFLC.A10 gene in spring-type rapeseed, nor in ancestral ‘A’ genome species B. rapa genotypes. Our results suggest that the insertion may have occurred in winter rapeseed after B. napus speciation. Conclusions Our findings strongly suggest that (i) BnFLC.A10 is the gene underlying qFT10-4, the QTL for phenotypic diversity of flowering time in the TN-DH population, (ii) the allelic diversity caused by MITE insertion/deletion upstream of BnFLC.A10 is one of the major causes of differentiation of winter and spring genotypes in rapeseed and (iii) winter rapeseed has evolved from spring genotypes through selection pressure at the BnFLC.A10 locus, enabling expanded cultivation of rapeseed along the route of Brassica domestication. PMID:23241244
Hou, Jinna; Long, Yan; Raman, Harsh; Zou, Xiaoxiao; Wang, Jing; Dai, Shutao; Xiao, Qinqin; Li, Cong; Fan, Longjiang; Liu, Bin; Meng, Jinling
2012-12-15
Rapeseed (Brassica napus L.) has spring and winter genotypes adapted to different growing seasons. Winter genotypes do not flower before the onset of winter, thus leading to a longer vegetative growth period that promotes the accumulation and allocation of more resources to seed production. The development of winter genotypes enabled the rapeseed to spread rapidly from southern to northern Europe and other temperate regions of the world. The molecular basis underlying the evolutionary transition from spring- to winter- type rapeseed is not known, however, and needs to be elucidated. We fine-mapped the spring environment specific quantitative trait locus (QTL) for flowering time, qFT10-4,in a doubled haploid (DH) mapping population of rapeseed derived from a cross between Tapidor (winter-type) and Ningyou7 (semi-winter) and delimited the qFT10-4 to an 80-kb region on chromosome A10 of B. napus. The BnFLC.A10 gene, an ortholog of FLOWERING LOCUS C (FLC) in Arabidopsis, was cloned from the QTL. We identified 12 polymorphic sites between BnFLC.A10 parental alleles of the TN-DH population in the upstream region and in intron 1. Expression of both BnFLC.A10 alleles decreased during vernalization, but decreased more slowly in the winter parent Tapidor. Haplotyping and association analysis showed that one of the polymorphic sites upstream of BnFLC.A10 is strongly associated with the vernalization requirement of rapeseed (r2 = 0.93, χ2 = 0.50). This polymorphic site is derived from a Tourist-like miniature inverted-repeat transposable element (MITE) insertion/deletion in the upstream region of BnFLC.A10. The MITE sequence was not present in the BnFLC.A10 gene in spring-type rapeseed, nor in ancestral 'A' genome species B. rapa genotypes. Our results suggest that the insertion may have occurred in winter rapeseed after B. napus speciation. Our findings strongly suggest that (i) BnFLC.A10 is the gene underlying qFT10-4, the QTL for phenotypic diversity of flowering time in the TN-DH population, (ii) the allelic diversity caused by MITE insertion/deletion upstream of BnFLC.A10 is one of the major causes of differentiation of winter and spring genotypes in rapeseed and (iii) winter rapeseed has evolved from spring genotypes through selection pressure at the BnFLC.A10 locus, enabling expanded cultivation of rapeseed along the route of Brassica domestication.
Polymorphic Alu insertions among Mayan populations.
Herrera, R J; Rojas, D P; Terreros, M C
2007-01-01
The Mayan homeland within Mesoamerica spans five countries: Belize, El Salvador, Guatemala, Honduras and Mexico. There are indications that the people we call the Maya migrated from the north to the highlands of Guatemala as early as 4000 B.C. Their existence was village-based and agricultural. The culture of these Preclassic Mayans owes much to the earlier Olmec civilization, which flourished in the southern portion of North America. In this study, four different Mayan groups were examined to assess their genetic variability. Ten polymorphic Alu insertion (PAI) loci were employed to ascertain the genetic affinities among these Mayan groups. North American, African, European and Asian populations were also examined as reference populations. Our results suggest that the Mayan groups examined in this study are not genetically homogeneous.
Characterization of a highly polymorphic region 5′ to JH in the human immunoglobulin heavy chain
Silva, Alcino J.; Johnson, John P.; White, Raymond L.
1987-01-01
A cloned DNA segment 1.25 kilobases (kb) upstream from the joining segments of the human heavy chain immunoglobulin gene revealed extensive polymorphic variation at this locus, and the polymorphic pattern was stably transmitted to the next generation. Genomic restriction analysis showed that the polymorphism was caused by insertions/deletions within an MspI/BamHI fragment. Sequencing of one allele, 848 base pairs (bp) long, revealed eleven 50-base-pair tandem repeats. A second allele, 648 bp long, was cloned from a human genomic cosmid library, sequenced, and found to contain four fewer repeats than the first allele. A survey of 186 chromosomes from unrelated individuals of primarily northern European descent revealed at least six alleles. Images PMID:2884636
Peyvandi, F; Garagiola, I; Palla, R; Marziliano, N; Mannucci, P M
2005-11-01
Polymorphic variants in the gene encoding factor VII (F7) affect the plasma levels of this coagulation protein and modify the clinical phenotype of FVII deficiency in some patients. In this study we report the in vitro functional analysis of a novel polymorphic variant located in the 3' untranslated region of F7: g.11293_11294insAA. To determine whether this variant regulates FVII expression, we initially compared an expression vector containing FVII cDNA with g.11293_11294insAA with the FVII wild-type (WT) construct. The kinetics of mRNA production showed that the insertion decreases the steady-state FVII mRNA levels. To assess whether the insertion influences the phenotype of FVII-deficient patients, we evaluated its effect on the expression of FVII in a patient with severe FVII deficiency (undetectable FVII activity and antigen) carrying two additional homozygous missense variations (p.Arg277Cys and p.Arg353Gln). The two substitutions alone reduced the expression of FVII activity and antigen in vitro, but with the insertion polymorphism in our expression vector the patient's phenotype of undetectable plasma FVII was recapitulated. The insertion polymorphism in the 3' untranslated region of F7 is another modifier of FVII expression that might explain the poor genotype-phenotype correlation in some FVII-deficient patients. Copyright 2005 Wiley-Liss, Inc.
Discrimination of SHV β-Lactamase Genes by Restriction Site Insertion-PCR
Chanawong, Aroonwadee; M'Zali, Fatima Hannachi; Heritage, John; Lulitanond, Aroonlug; Hawkey, Peter Michael
2001-01-01
Restriction site insertion-PCR (RSI-PCR) is a simple, rapid technique for detection of point mutations. This technique exploits primers with one to three base mismatches near the 3′ end to modulate a restriction site. We have developed this technique to identify described mutations of the blaSHV genes for differentiation of SHV variants that cannot be distinguished easily by other techniques. To validate this method, eight standard strains were used, each producing a different SHV β-lactamase: SHV-1, SHV-2, SHV-3, SHV-4, SHV-5, SHV-6, SHV-8, and SHV-18. Mismatch primers were designed to detect mutations affecting amino acids at positions 8 (SspI), 179 (HinfI), 205 (PstI), 238 (Gly→Ala) (BsrI), and 240 (NruI) of blaSHV genes. All amplimers of the blaSHV genes used in this study yielded the predicted restriction endonuclease digestion products. In addition, this study also makes theoretical identification of blaSHV-6, blaSHV-8, and 12 novel blaSHV variants using the PCR-restriction fragment length polymorphism (RFLP) technique possible. By using a combination of PCR-RFLP and RSI-PCR techniques, up to 27 SHV variants can now be distinguished rapidly and reliably. These simple techniques are readily applied to epidemiological studies of the SHV β-lactamases and may be extended to the characterisation of other resistance determinants. PMID:11408231
Gardiner, Gillian E.; Heinemann, Christine; Bruce, Andrew W.; Beuerman, Dee; Reid, Gregor
2002-01-01
Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 are well-characterized probiotic strains with efficacy in the prevention and treatment of urogenital infections in women. The aim of the present study was to apply a molecular biology-based methodology for the detection of these strains and L. rhamnosus GG (a commercially available intestinal probiotic) in the human vagina in order to assess probiotic persistence at this site. Ten healthy women inserted vaginally a capsule containing either a combination of strains GR-1 and RC-14 or the GG strain for 3 consecutive nights. Vaginal swabs taken before and at various time points after probiotic insertion were analyzed, and the Lactobacillus flora was assessed by randomly amplified polymorphic DNA (RAPD) analysis. This method generated discrete DNA fingerprints for GR-1, RC-14, and GG and enabled successful detection of these strains in the vagina. Strain GR-1 and/or strain RC-14 was found to persist in the vaginal tract for up to 19 days after vaginal instillation, while L. rhamnosus GG was detectable for up to 5 days postadministration. In conclusion, the fates of probiotic L. rhamnosus and L. fermentum strains were successfully monitored in the human vagina by RAPD analysis. This technique provides molecular biology-based evidence that RC-14 and GR-1, strains selected as urogenital probiotics, persist in the human vagina and may be more suited to vaginal colonization than L. rhamnosus GG. This highlights the importance of proper selection of strains for urogenital probiotic applications. PMID:11777835
Polymorphic integrations of an endogenous gammaretrovirus in the mule deer genome.
Elleder, Daniel; Kim, Oekyung; Padhi, Abinash; Bankert, Jason G; Simeonov, Ivan; Schuster, Stephan C; Wittekindt, Nicola E; Motameny, Susanne; Poss, Mary
2012-03-01
Endogenous retroviruses constitute a significant genomic fraction in all mammalian species. Typically they are evolutionarily old and fixed in the host species population. Here we report on a novel endogenous gammaretrovirus (CrERVγ; for cervid endogenous gammaretrovirus) in the mule deer (Odocoileus hemionus) that is insertionally polymorphic among individuals from the same geographical location, suggesting that it has a more recent evolutionary origin. Using PCR-based methods, we identified seven CrERVγ proviruses and demonstrated that they show various levels of insertional polymorphism in mule deer individuals. One CrERVγ provirus was detected in all mule deer sampled but was absent from white-tailed deer, indicating that this virus originally integrated after the split of the two species, which occurred approximately one million years ago. There are, on average, 100 CrERVγ copies in the mule deer genome based on quantitative PCR analysis. A CrERVγ provirus was sequenced and contained intact open reading frames (ORFs) for three virus genes. Transcripts were identified covering the entire provirus. CrERVγ forms a distinct branch of the gammaretrovirus phylogeny, with the closest relatives of CrERVγ being endogenous gammaretroviruses from sheep and pig. We demonstrated that white-tailed deer (Odocoileus virginianus) and elk (Cervus canadensis) DNA contain proviruses that are closely related to mule deer CrERVγ in a conserved region of pol; more distantly related sequences can be identified in the genome of another member of the Cervidae, the muntjac (Muntiacus muntjak). The discovery of a novel transcriptionally active and insertionally polymorphic retrovirus in mammals could provide a useful model system to study the dynamic interaction between the host genome and an invading retrovirus.
Okada, Kazuma; Wada, Masato; Moriya, Shigeki; Katayose, Yuichi; Fujisawa, Hiroko; Wu, Jianzhong; Kanamori, Hiroyuki; Kurita, Kanako; Sasaki, Harumi; Fujii, Hiroshi; Terakami, Shingo; Iwanami, Hiroshi; Yamamoto, Toshiya; Abe, Kazuyuki
2016-11-01
Determining the molecular mechanism of fruit tree architecture is important for tree management and fruit production. An apple mutant 'McIntosh Wijcik', which was discovered as a bud mutation from 'McIntosh', exhibits a columnar growth phenotype that is controlled by a single dominant gene, Co. In this study, the mutation and the Co gene were analyzed. Fine mapping narrowed the Co region to a 101 kb region. Sequence analysis of the Co region and the original wild-type co region identified an insertion mutation of an 8202 bp long terminal repeat (LTR) retroposon in the Co region. Segregation analysis using a DNA marker based on the insertion polymorphism showed that the LTR retroposon was closely associated with the columnar growth phenotype. RNA-seq and RT-PCR analysis identified a promising Co candidate gene (91071-gene) within the Co region that is specifically expressed in 'McIntosh Wijcik' but not in 'McIntosh'. The 91071-gene was located approximately 16 kb downstream of the insertion mutation and is predicted to encode a 2-oxoglutarate-dependent dioxygenase involved in an unknown reaction. Overexpression of the 91071-gene in transgenic tobaccos and apples resulted in phenotypes with short internodes, like columnar apples. These data suggested that the 8202 bp retroposon insertion in 'McIntosh Wijcik' is associated with the short internodes of the columnar growth phenotype via upregulated expression of the adjacent 91071-gene. Furthermore, the DNA marker based on the insertion polymorphism could be useful for the marker-assisted selection of columnar apples.
Naturally occurring deletions of hunchback binding sites in the even-skipped stripe 3+7 enhancer.
Palsson, Arnar; Wesolowska, Natalia; Reynisdóttir, Sigrún; Ludwig, Michael Z; Kreitman, Martin
2014-01-01
Changes in regulatory DNA contribute to phenotypic differences within and between taxa. Comparative studies show that many transcription factor binding sites (TFBS) are conserved between species whereas functional studies reveal that some mutations segregating within species alter TFBS function. Consistently, in this analysis of 13 regulatory elements in Drosophila melanogaster populations, single base and insertion/deletion polymorphism are rare in characterized regulatory elements. Experimentally defined TFBS are nearly devoid of segregating mutations and, as has been shown before, are quite conserved. For instance 8 of 11 Hunchback binding sites in the stripe 3+7 enhancer of even-skipped are conserved between D. melanogaster and Drosophila virilis. Oddly, we found a 72 bp deletion that removes one of these binding sites (Hb8), segregating within D. melanogaster. Furthermore, a 45 bp deletion polymorphism in the spacer between the stripe 3+7 and stripe 2 enhancers, removes another predicted Hunchback site. These two deletions are separated by ∼250 bp, sit on distinct haplotypes, and segregate at appreciable frequency. The Hb8Δ is at 5 to 35% frequency in the new world, but also shows cosmopolitan distribution. There is depletion of sequence variation on the Hb8Δ-carrying haplotype. Quantitative genetic tests indicate that Hb8Δ affects developmental time, but not viability of offspring. The Eve expression pattern differs between inbred lines, but the stripe 3 and 7 boundaries seem unaffected by Hb8Δ. The data reveal segregating variation in regulatory elements, which may reflect evolutionary turnover of characterized TFBS due to drift or co-evolution.
Sanchez-Luque, Francisco J; Richardson, Sandra R; Faulkner, Geoffrey J
2016-01-01
Mobile genetic elements (MGEs) are of critical importance in genomics and developmental biology. Polymorphic and somatic MGE insertions have the potential to impact the phenotype of an individual, depending on their genomic locations and functional consequences. However, the identification of polymorphic and somatic insertions among the plethora of copies residing in the genome presents a formidable technical challenge. Whole genome sequencing has the potential to address this problem; however, its efficacy depends on the abundance of cells carrying the new insertion. Robust detection of somatic insertions present in only a subset of cells within a given sample can also be prohibitively expensive due to a requirement for high sequencing depth. Here, we describe retrotransposon capture sequencing (RC-seq), a sequence capture approach in which Illumina libraries are enriched for fragments containing the 5' and 3' termini of specific MGEs. RC-seq allows the detection of known polymorphic insertions present in an individual, as well as the identification of rare or private germline insertions not previously described. Furthermore, RC-seq can be used to detect and characterize somatic insertions, providing a valuable tool to elucidate the extent and characteristics of MGE activity in healthy tissues and in various disease states.
A Predictive Model of Intein Insertion Site for Use in the Engineering of Molecular Switches
Apgar, James; Ross, Mary; Zuo, Xiao; Dohle, Sarah; Sturtevant, Derek; Shen, Binzhang; de la Vega, Humberto; Lessard, Philip; Lazar, Gabor; Raab, R. Michael
2012-01-01
Inteins are intervening protein domains with self-splicing ability that can be used as molecular switches to control activity of their host protein. Successfully engineering an intein into a host protein requires identifying an insertion site that permits intein insertion and splicing while allowing for proper folding of the mature protein post-splicing. By analyzing sequence and structure based properties of native intein insertion sites we have identified four features that showed significant correlation with the location of the intein insertion sites, and therefore may be useful in predicting insertion sites in other proteins that provide native-like intein function. Three of these properties, the distance to the active site and dimer interface site, the SVM score of the splice site cassette, and the sequence conservation of the site showed statistically significant correlation and strong predictive power, with area under the curve (AUC) values of 0.79, 0.76, and 0.73 respectively, while the distance to secondary structure/loop junction showed significance but with less predictive power (AUC of 0.54). In a case study of 20 insertion sites in the XynB xylanase, two features of native insertion sites showed correlation with the splice sites and demonstrated predictive value in selecting non-native splice sites. Structural modeling of intein insertions at two sites highlighted the role that the insertion site location could play on the ability of the intein to modulate activity of the host protein. These findings can be used to enrich the selection of insertion sites capable of supporting intein splicing and hosting an intein switch. PMID:22649521
A simple repeat polymorphism in the MITF-M promoter is a key regulator of white spotting in dogs.
Baranowska Körberg, Izabella; Sundström, Elisabeth; Meadows, Jennifer R S; Rosengren Pielberg, Gerli; Gustafson, Ulla; Hedhammar, Åke; Karlsson, Elinor K; Seddon, Jennifer; Söderberg, Arne; Vilà, Carles; Zhang, Xiaolan; Åkesson, Mikael; Lindblad-Toh, Kerstin; Andersson, Göran; Andersson, Leif
2014-01-01
The white spotting locus (S) in dogs is colocalized with the MITF (microphtalmia-associated transcription factor) gene. The phenotypic effects of the four S alleles range from solid colour (S) to extreme white spotting (s(w)). We have investigated four candidate mutations associated with the s(w) allele, a SINE insertion, a SNP at a conserved site and a simple repeat polymorphism all associated with the MITF-M promoter as well as a 12 base pair deletion in exon 1B. The variants associated with white spotting at all four loci were also found among wolves and we conclude that none of these could be a sole causal mutation, at least not for extreme white spotting. We propose that the three canine white spotting alleles are not caused by three independent mutations but represent haplotype effects due to different combinations of causal polymorphisms. The simple repeat polymorphism showed extensive diversity both in dogs and wolves, and allele-sharing was common between wolves and white spotted dogs but was non-existent between solid and spotted dogs as well as between wolves and solid dogs. This finding was unexpected as Solid is assumed to be the wild-type allele. The data indicate that the simple repeat polymorphism has been a target for selection during dog domestication and breed formation. We also evaluated the significance of the three MITF-M associated polymorphisms with a Luciferase assay, and found conclusive evidence that the simple repeat polymorphism affects promoter activity. Three alleles associated with white spotting gave consistently lower promoter activity compared with the allele associated with solid colour. We propose that the simple repeat polymorphism affects cooperativity between transcription factors binding on either flanking sides of the repeat. Thus, both genetic and functional evidence show that the simple repeat polymorphism is a key regulator of white spotting in dogs.
A Simple Repeat Polymorphism in the MITF-M Promoter Is a Key Regulator of White Spotting in Dogs
Meadows, Jennifer R. S.; Rosengren Pielberg, Gerli; Gustafson, Ulla; Hedhammar, Åke; Karlsson, Elinor K.; Seddon, Jennifer; Söderberg, Arne; Vilà, Carles; Zhang, Xiaolan; Åkesson, Mikael; Lindblad-Toh, Kerstin; Andersson, Göran; Andersson, Leif
2014-01-01
The white spotting locus (S) in dogs is colocalized with the MITF (microphtalmia-associated transcription factor) gene. The phenotypic effects of the four S alleles range from solid colour (S) to extreme white spotting (sw). We have investigated four candidate mutations associated with the sw allele, a SINE insertion, a SNP at a conserved site and a simple repeat polymorphism all associated with the MITF-M promoter as well as a 12 base pair deletion in exon 1B. The variants associated with white spotting at all four loci were also found among wolves and we conclude that none of these could be a sole causal mutation, at least not for extreme white spotting. We propose that the three canine white spotting alleles are not caused by three independent mutations but represent haplotype effects due to different combinations of causal polymorphisms. The simple repeat polymorphism showed extensive diversity both in dogs and wolves, and allele-sharing was common between wolves and white spotted dogs but was non-existent between solid and spotted dogs as well as between wolves and solid dogs. This finding was unexpected as Solid is assumed to be the wild-type allele. The data indicate that the simple repeat polymorphism has been a target for selection during dog domestication and breed formation. We also evaluated the significance of the three MITF-M associated polymorphisms with a Luciferase assay, and found conclusive evidence that the simple repeat polymorphism affects promoter activity. Three alleles associated with white spotting gave consistently lower promoter activity compared with the allele associated with solid colour. We propose that the simple repeat polymorphism affects cooperativity between transcription factors binding on either flanking sides of the repeat. Thus, both genetic and functional evidence show that the simple repeat polymorphism is a key regulator of white spotting in dogs. PMID:25116146
Clark, S. H.; Hilliker, A. J.; Chovnick, A.
1988-01-01
This report presents the results of a recombination experiment designed to question the existence of special sites for the initiation or termination of a recombination heteroduplex within the region of the rosy locus. Intragenic recombination events were monitored between two physically separated rosy mutant alleles ry(301) and ry(2) utilizing DNA restriction site polymorphisms as genetic markers. Both ry(301) and ry(2) are known from previous studies to be associated with gene conversion frequencies an order of magnitude lower than single site mutations. The mutations are associated with large, well defined insertions located as internal sites within the locus in prior intragenic mapping studies. On the molecular map, they represent large insertions approximately 2.7 kb apart in the second and third exons, respectively, of the XDH coding region. The present study monitors intragenic recombination in a mutant heterozygous genotype in which DNA homology is disrupted by these large discontinuities, greater than the region of DNA homology and flanking both sides of the locus. If initiation/or termination requires separate sites at either end of the locus, then intragenic recombination within the rosy locus of the heterozygote should be eliminated. Contrary to expectation, significant recombination between these sites is seen. PMID:2834266
Kim, Junho; Maeng, Ju Heon; Lim, Jae Seok; Son, Hyeonju; Lee, Junehawk; Lee, Jeong Ho; Kim, Sangwoo
2016-10-15
Advances in sequencing technologies have remarkably lowered the detection limit of somatic variants to a low frequency. However, calling mutations at this range is still confounded by many factors including environmental contamination. Vector contamination is a continuously occurring issue and is especially problematic since vector inserts are hardly distinguishable from the sample sequences. Such inserts, which may harbor polymorphisms and engineered functional mutations, can result in calling false variants at corresponding sites. Numerous vector-screening methods have been developed, but none could handle contamination from inserts because they are focusing on vector backbone sequences alone. We developed a novel method-Vecuum-that identifies vector-originated reads and resultant false variants. Since vector inserts are generally constructed from intron-less cDNAs, Vecuum identifies vector-originated reads by inspecting the clipping patterns at exon junctions. False variant calls are further detected based on the biased distribution of mutant alleles to vector-originated reads. Tests on simulated and spike-in experimental data validated that Vecuum could detect 93% of vector contaminants and could remove up to 87% of variant-like false calls with 100% precision. Application to public sequence datasets demonstrated the utility of Vecuum in detecting false variants resulting from various types of external contamination. Java-based implementation of the method is available at http://vecuum.sourceforge.net/ CONTACT: swkim@yuhs.acSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Wiltshire, Esko J; Peña, Alexia S; MacKenzie, Karen; Bose-Sundernathan, Tulika; Gent, Roger; Couper, Jennifer J
2015-02-01
To determine the effect of polymorphisms in NOS3 and folate pathway enzymes on vascular function and folate status and endothelial response to folate in children with diabetes or obesity. A total of 244 subjects (age 13.8 ± 2.8 years, 125 males) were studied for NOS3 and/or folate pathway polymorphisms using polymerase chain reaction/restriction fragment length polymorphism, including at baseline: 139 with type 1 diabetes; 58 with obesity; and 47 controls. The effect of NOS3 genotype on endothelial response to folate (5 mg) was assessed in 85 subjects with diabetes and 28 obese subjects who received active treatment during intervention trials. Vascular function (flow-mediated dilatation [FMD] and glyceryl trinitrate-mediated dilatation), clinical, and biochemical measurements were assessed at baseline and 8 weeks in folate intervention studies. Folate pathway enzyme and NOS3 polymorphisms did not significantly affect baseline vascular function. The polymorphism in intron 4 of endothelial nitric oxide synthase altered endothelial response to folate significantly: in subjects with diabetes FMD improved by 6.4 ± 5% (insertion carriers) vs 2.3 ± 6.6% (deletion carriers), P = .01; in obese subjects FMD improved by 1.8 ± 5.4% (insertion carriers) and deteriorated by -3.2 ± 7.2% (deletion carriers), P = .05. More subjects carrying the insertion normalized FMD after folate supplementation (insertion 64% vs deletion 28%, χ(2) = 10.14, P = .001). A NOS3 polymorphism predicts endothelial response to folate in children with diabetes or obesity, with implications for vascular risk and folate intervention studies. Copyright © 2015 Elsevier Inc. All rights reserved.
Polymorphic site index curves for red fir in California and southern Oregon
K. Leroy Dolph
1991-01-01
Polymorphic site index curves were developed from stem analysis data of 194 dominant red fir trees in California and southern Oregon. Site index was based on breast-height age and total tree height, with a base age of 50 years at breast height. Site index curves for breast height ages 10 to 160 years are presented for approximate estimates of site index. For more...
[Clustered regularly interspaced short palindromic repeats (CRISPR) site in Bacillus anthracis].
Gao, Zhiqi; Wang, Dongshu; Feng, Erling; Wang, Bingxiang; Hui, Yiming; Han, Shaobo; Jiao, Lei; Liu, Xiankai; Wang, Hengliang
2014-11-04
To investigate the polymorphism of clustered regularly interspaced short palindromic repeats (CRISPR) in Bacillu santhracis and the application to molecular typing based on the polymorphism of CRISPR in B. anthracis. We downloaded the whole genome sequence of 6 B. anthracis strains and extracted the CRISPR sites. We designed the primers of CRISPR sites and amplified the CRISPR fragments in 193 B. anthracis strains by PCR and sequenced these fragments. In order to reveal the polymorphism of CRISPR in B. anthracis, wealigned all the extracted sequences and sequenced results by local blasting. At the same time, we also analyzed the CRISPR sites in B. cereus and B. thuringiensis. We did not find any polymorphism of CRISPR in B. anthracis. The molecular typing approach based on CRISPR polymorphism is not suitable for B. anthracis, but it is possible for us to distinguish B. anthracis from B. cereus and B. thuringiensis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Micklos, David A.
2006-10-30
This project achieved its goal of implementing a nationwide training program to introduce high school biology teachers to the key uses and societal implications of human DNA polymorphisms. The 2.5-day workshop introduced high school biology faculty to a laboratory-based unit on human DNA polymorphisms â which provides a uniquely personal perspective on the science and Ethical, Legal and Social Implications (ELSI) of the Human Genome Project. As proposed, 12 workshops were conducted at venues across the United States. The workshops were attended by 256 high school faculty, exceeding proposed attendance of 240 by 7%. Each workshop mixed theoretical, laboratory, andmore » computer work with practical and ethical implications. Program participants learned simplified lab techniques for amplifying three types of chromosomal polymorphisms: an Alu insertion (PV92), a VNTR (pMCT118/D1S80), and single nucleotide polymorphisms (SNPs) in the mitochondrial control region. These polymorphisms illustrate the use of DNA variations in disease diagnosis, forensic biology, and identity testing - and provide a starting point for discussing the uses and potential abuses of genetic technology. Participants also learned how to use their Alu and mitochondrial data as an entrée to human population genetics and evolution. Our work to simplify lab techniques for amplifying human DNA polymorphisms in educational settings culminated with the release in 1998 of three Advanced Technology (AT) PCR kits by Carolina Biological Supply Company, the nationâÂÂs oldest educational science supplier. The kits use a simple 30-minute method to isolate template DNA from hair sheaths or buccal cells and streamlined PCR chemistry based on Pharmacia Ready-To-Go Beads, which incorporate Taq polymerase, deoxynucleotide triphosphates, and buffer in a freeze-dried pellet. These kits have greatly simplified teacher implementation of human PCR labs, and their use is growing at a rapid pace. Sales of human polymorphism kits by Carolina Biological rose from 700 units in 1999 to 1,132 in 2000 â a 62% increase. Competing kits using the Alu system, and based substantially on our earlier work, are also marketed by Biorad and Edvotek. In parallel with the lab experiments, we developed a suite of database/statistical applications and easy-to-use interfaces that allow students to use their own DNA data to explore human population genetics and to test theories of human evolution. Database searches and statistical analyses are launched from a centralized workspace. Workshop participants were introduced to these and other resources available at the DNALC WWW site (http://vector.cshl.org/bioserver/): 1) Allele Server tests Hardy-Weinberg equilibrium and statistically compares PV92 data from world populations. 2) Sequence Server uses DNA sequence data to search Genbank using BLASTN, compare sequences using CLUSTALW, and create phylogenetic trees using PHYLIP. 3) Simulation Server uses a Monte Carlo generator to model the long-term effects of drift, selection, and population bottlenecks. By targeting motivated and innovative biology faculty, we believe that this project offered a cost-effective means to bring high school biology education up-to-the-minute with genomic biology. The workshop reached a target audience of highly professional faculty who have already implemented hands-on labs in molecular genetics and many of whom offer laboratory electives in biotechnology. Many attend professional meetings, develop curriculum, collaborate with scientists, teach faculty workshops, and manage equipment-sharing programs. These individuals are life-long learners, anxious for deeper insight and additional training to further extend their leadership. This contention was supported by data from a mail survey, conducted in February-March 2000 and 2001, of 256 faculty who participated in workshops conducted during the current term of DOE support. Seventy percent of participants responded, providing direct reports on how their teaching behavior had changed since taking the DOE workshop. About nine of ten respondents said they had provided new classroom materials and first-hand accounts of DNA typing, sequencing, or PCR. Three-fourths had introduced new units on human molecular genetics. Most strikingly, half had students use PCR to amplify their own insertion polymorphisms (PV92), and better than one-fourth amplified a VNTR polymorphism and the mitochondrial control region. One in five had mitochondrial DNA sequenced by the DNALC Sequencing Service. A majority (58%) used online materials at the DNALC WWW site, and 28% analyzed student polymorphism data with Bioservers at the DNALC site. A majority (58%) assisted other faculty with student labs on polymorphisms, reaching an additional 786 teachers.« less
Rates and patterns of great ape retrotransposition.
Hormozdiari, Fereydoun; Konkel, Miriam K; Prado-Martinez, Javier; Chiatante, Giorgia; Herraez, Irene Hernando; Walker, Jerilyn A; Nelson, Benjamin; Alkan, Can; Sudmant, Peter H; Huddleston, John; Catacchio, Claudia R; Ko, Arthur; Malig, Maika; Baker, Carl; Marques-Bonet, Tomas; Ventura, Mario; Batzer, Mark A; Eichler, Evan E
2013-08-13
We analyzed 83 fully sequenced great ape genomes for mobile element insertions, predicting a total of 49,452 fixed and polymorphic Alu and long interspersed element 1 (L1) insertions not present in the human reference assembly and assigning each retrotransposition event to a different time point during great ape evolution. We used these homoplasy-free markers to construct a mobile element insertions-based phylogeny of humans and great apes and demonstrate their differential power to discern ape subspecies and populations. Within this context, we find a good correlation between L1 diversity and single-nucleotide polymorphism heterozygosity (r(2) = 0.65) in contrast to Alu repeats, which show little correlation (r(2) = 0.07). We estimate that the "rate" of Alu retrotransposition has differed by a factor of 15-fold in these lineages. Humans, chimpanzees, and bonobos show the highest rates of Alu accumulation--the latter two since divergence 1.5 Mya. The L1 insertion rate, in contrast, has remained relatively constant, with rates differing by less than a factor of three. We conclude that Alu retrotransposition has been the most variable form of genetic variation during recent human-great ape evolution, with increases and decreases occurring over very short periods of evolutionary time.
Delprat, Alejandra; Negre, Bàrbara; Puig, Marta; Ruiz, Alfredo
2009-11-18
Transposable elements (TEs) are responsible for the generation of chromosomal inversions in several groups of organisms. However, in Drosophila and other Dipterans, where inversions are abundant both as intraspecific polymorphisms and interspecific fixed differences, the evidence for a role of TEs is scarce. Previous work revealed that the transposon Galileo was involved in the generation of two polymorphic inversions of Drosophila buzzatii. To assess the impact of TEs in Drosophila chromosomal evolution and shed light on the mechanism involved, we isolated and sequenced the two breakpoints of another widespread polymorphic inversion from D. buzzatii, 2z(3). In the non inverted chromosome, the 2z(3) distal breakpoint was located between genes CG2046 and CG10326 whereas the proximal breakpoint lies between two novel genes that we have named Dlh and Mdp. In the inverted chromosome, the analysis of the breakpoint sequences revealed relatively large insertions (2,870-bp and 4,786-bp long) including two copies of the transposon Galileo (subfamily Newton), one at each breakpoint, plus several other TEs. The two Galileo copies: (i) are inserted in opposite orientation; (ii) present exchanged target site duplications; and (iii) are both chimeric. Our observations provide the best evidence gathered so far for the role of TEs in the generation of Drosophila inversions. In addition, they show unequivocally that ectopic recombination is the causative mechanism. The fact that the three polymorphic D. buzzatii inversions investigated so far were generated by the same transposon family is remarkable and is conceivably due to Galileo's unusual structure and current (or recent) transpositional activity.
Kang, Sang Wook; Kim, Su Kang; Jung, Hee-Jae; Kim, Kwan-Il; Kim, Jinju
2016-01-01
The relationship between polymorphism of the angiotensin I converting enzyme (ACE) gene and chronic obstructive pulmonary disease (COPD) has been examined in many previous studies. However, their results were controversial. Therefore, we performed a meta-analysis to evaluate the relationship between the ACE gene and the risk of COPD. Fourteen case-control studies were included in this meta-analysis. The pooled p value, odds ratio (OR), and 95% confidence interval (95% CI) were used to investigate the strength of the association. The meta-analysis was performed using comprehensive meta-analysis software. Our meta-analysis results revealed that ACE polymorphisms were not related to the risk of COPD (p > 0.05 in each model). In further analyses based on ethnicity, we observed an association between insertion/deletion polymorphism of the ACE gene and risk of COPD in the Asian population (codominant 2, OR = 3.126, 95% CI = 1.919–5.093, p < 0.001; recessive, OR = 3.326, 95% CI = 2.190–5.050, p < 0.001) but not in the Caucasian population (p > 0.05 in each model). In conclusion, the present meta-analysis indicated that the insertion/deletion polymorphism of the ACE gene may be associated with susceptibility to COPD in the Asian population but not in the Caucasian population. However, the results of the present meta-analysis need to be confirmed in a larger sample. PMID:27830153
DOE Office of Scientific and Technical Information (OSTI.GOV)
David. A Micklos
2006-10-30
This project achieved its goal of implementing a nationwide training program to introduce high school biology teachers to the key uses and societal implications of human DNA polymorphisms. The 2.5-day workshop introduced high school biology faculty to a laboratory-based unit on human DNA polymorphisms – which provides a uniquely personal perspective on the science and Ethical, Legal and Social Implications (ELSI) of the Human Genome Project. As proposed, 12 workshops were conducted at venues across the United States. The workshops were attended by 256 high school faculty, exceeding proposed attendance of 240 by 7%. Each workshop mixed theoretical, laboratory, andmore » computer work with practical and ethical implications. Program participants learned simplified lab techniques for amplifying three types of chromosomal polymorphisms: an Alu insertion (PV92), a VNTR (pMCT118/D1S80), and single nucleotide polymorphisms (SNPs) in the mitochondrial control region. These polymorphisms illustrate the use of DNA variations in disease diagnosis, forensic biology, and identity testing - and provide a starting point for discussing the uses and potential abuses of genetic technology. Participants also learned how to use their Alu and mitochondrial data as an entrée to human population genetics and evolution. Our work to simplify lab techniques for amplifying human DNA polymorphisms in educational settings culminated with the release in 1998 of three Advanced Technology (AT) PCR kits by Carolina Biological Supply Company, the nation’s oldest educational science supplier. The kits use a simple 30-minute method to isolate template DNA from hair sheaths or buccal cells and streamlined PCR chemistry based on Pharmacia Ready-To-Go Beads, which incorporate Taq polymerase, deoxynucleotide triphosphates, and buffer in a freeze-dried pellet. These kits have greatly simplified teacher implementation of human PCR labs, and their use is growing at a rapid pace. Sales of human polymorphism kits by Carolina Biological rose from 700 units in 1999 to 1,132 in 2000 – a 62% increase. Competing kits using the Alu system, and based substantially on our earlier work, are also marketed by Biorad and Edvotek. In parallel with the lab experiments, we developed a suite of database/statistical applications and easy-to-use interfaces that allow students to use their own DNA data to explore human population genetics and to test theories of human evolution. Database searches and statistical analyses are launched from a centralized workspace. Workshop participants were introduced to these and other resources available at the DNALC WWW site (http://vector.cshl.org/bioserver/): 1) Allele Server tests Hardy-Weinberg equilibrium and statistically compares PV92 data from world populations. 2) Sequence Server uses DNA sequence data to search Genbank using BLASTN, compare sequences using CLUSTALW, and create phylogenetic trees using PHYLIP. 3) Simulation Server uses a Monte Carlo generator to model the long-term effects of drift, selection, and population bottlenecks. By targeting motivated and innovative biology faculty, we believe that this project offered a cost-effective means to bring high school biology education up-to-the-minute with genomic biology. The workshop reached a target audience of highly professional faculty who have already implemented hands-on labs in molecular genetics and many of whom offer laboratory electives in biotechnology. Many attend professional meetings, develop curriculum, collaborate with scientists, teach faculty workshops, and manage equipment-sharing programs. These individuals are life-long learners, anxious for deeper insight and additional training to further extend their leadership. This contention was supported by data from a mail survey, conducted in February-March 2000 and 2001, of 256 faculty who participated in workshops conducted during the current term of DOE support. Seventy percent of participants responded, providing direct reports on how their teaching behavior had changed since taking the DOE workshop. About nine of ten respondents said they had provided new classroom materials and first-hand accounts of DNA typing, sequencing, or PCR. Three-fourths had introduced new units on human molecular genetics. Most strikingly, half had students use PCR to amplify their own insertion polymorphisms (PV92), and better than one-fourth amplified a VNTR polymorphism and the mitochondrial control region. One in five had mitochondrial DNA sequenced by the DNALC Sequencing Service. A majority (58%) used online materials at the DNALC WWW site, and 28% analyzed student polymorphism data with Bioservers at the DNALC site. A majority (58%) assisted other faculty with student labs on polymorphisms, reaching an additional 786 teachers.« less
Molecular characterization of Fagaceae species using inter-primer binding site (iPBS) markers.
Coutinho, João Paulo; Carvalho, Ana; Martín, Antonio; Lima-Brito, José
2018-04-01
Retrotransposons (RTNs) contribute for genome evolution, influencing its size and structure. We investigated the utility of the RTN-based markers inter-primer binding site (iPBS) for the molecular characterization of 25 Fagaceae species from genera Castanea, Fagus and Quercus. The assessment of genetic diversity, relationships and structure, as well as taxonomic classification of Fagaceae based on molecular data is important for definition of conservation, forestry management strategies and discrimination among natural hybrids and their parents since natural hybridization may increase with the climate changes. Here, iPBS primers designed by other authors were tested alone and combined. Some of them were discriminative, revealed polymorphism within and among taxa allowing the production of a total of 150 iPBS markers. In addition, several monomorphic iPBS markers were also amplified in each taxon. The UPGMA dendrogram based on the pooled iPBS data revealed 27% of genetic similarity among species. The individuals were clustered per genus and most of the oaks per infrageneric group corroborating the adopted taxonomy. Globally, the iPBS markers demonstrated suitability for DNA fingerprinting, determination of phylogenies and taxonomic discrimination in Fagaceae, and could constitute a useful and alternative tool for germplasm characterization, and for definition of conservation strategies and forestry management. Moreover, these markers would be useful for fingerprinting natural hybrids that share morphological similarities with their parents. Since iPBS markers could also enable insights about RTNs evolution, an eventual correlation among iPBS polymorphism, variability of RTN insertions and/or genome size in Fagaceae is discussed.
Berthier, Y; Thierry, D; Lemattre, M; Guesdon, J L
1994-01-01
A new insertion sequence was isolated from Xanthomonas campestris pv. dieffenbachiae. Sequence analysis showed that this element is 1,158 bp long and has 15-bp inverted repeat ends containing two mismatches. Comparison of this sequence with sequences in data bases revealed significant homology with Escherichia coli IS5. IS1051, which detected multiple restriction fragment length polymorphisms, was used as a probe to characterize strains from the pathovar dieffenbachiae. Images PMID:7906933
Reference genotype and exome data from an Australian Aboriginal population for health-based research
Tang, Dave; Anderson, Denise; Francis, Richard W.; Syn, Genevieve; Jamieson, Sarra E.; Lassmann, Timo; Blackwell, Jenefer M.
2016-01-01
Genetic analyses, including genome-wide association studies and whole exome sequencing (WES), provide powerful tools for the analysis of complex and rare genetic diseases. To date there are no reference data for Aboriginal Australians to underpin the translation of health-based genomic research. Here we provide a catalogue of variants called after sequencing the exomes of 72 Aboriginal individuals to a depth of 20X coverage in ∼80% of the sequenced nucleotides. We determined 320,976 single nucleotide variants (SNVs) and 47,313 insertions/deletions using the Genome Analysis Toolkit. We had previously genotyped a subset of the Aboriginal individuals (70/72) using the Illumina Omni2.5 BeadChip platform and found ~99% concordance at overlapping sites, which suggests high quality genotyping. Finally, we compared our SNVs to six publicly available variant databases, such as dbSNP and the Exome Sequencing Project, and 70,115 of our SNVs did not overlap any of the single nucleotide polymorphic sites in all the databases. Our data set provides a useful reference point for genomic studies on Aboriginal Australians. PMID:27070114
Tang, Dave; Anderson, Denise; Francis, Richard W; Syn, Genevieve; Jamieson, Sarra E; Lassmann, Timo; Blackwell, Jenefer M
2016-04-12
Genetic analyses, including genome-wide association studies and whole exome sequencing (WES), provide powerful tools for the analysis of complex and rare genetic diseases. To date there are no reference data for Aboriginal Australians to underpin the translation of health-based genomic research. Here we provide a catalogue of variants called after sequencing the exomes of 72 Aboriginal individuals to a depth of 20X coverage in ∼80% of the sequenced nucleotides. We determined 320,976 single nucleotide variants (SNVs) and 47,313 insertions/deletions using the Genome Analysis Toolkit. We had previously genotyped a subset of the Aboriginal individuals (70/72) using the Illumina Omni2.5 BeadChip platform and found ~99% concordance at overlapping sites, which suggests high quality genotyping. Finally, we compared our SNVs to six publicly available variant databases, such as dbSNP and the Exome Sequencing Project, and 70,115 of our SNVs did not overlap any of the single nucleotide polymorphic sites in all the databases. Our data set provides a useful reference point for genomic studies on Aboriginal Australians.
Yu, Qichao; Zhang, Wei; Zhang, Xiaolong; Zeng, Yongli; Wang, Yeming; Wang, Yanhui; Xu, Liqin; Huang, Xiaoyun; Li, Nannan; Zhou, Xinlan; Lu, Jie; Guo, Xiaosen; Li, Guibo; Hou, Yong; Liu, Shiping; Li, Bo
2017-09-01
Active retrotransposons play important roles during evolution and continue to shape our genomes today, especially in genetic polymorphisms underlying a diverse set of diseases. However, studies of human retrotransposon insertion polymorphisms (RIPs) based on whole-genome deep sequencing at the population level have not been sufficiently undertaken, despite the obvious need for a thorough characterization of RIPs in the general population. Herein, we present a novel and efficient computational tool called Specific Insertions Detector (SID) for the detection of non-reference RIPs. We demonstrate that SID is suitable for high-depth whole-genome sequencing data using paired-end reads obtained from simulated and real datasets. We construct a comprehensive RIP database using a large population of 90 Han Chinese individuals with a mean ×68 depth per individual. In total, we identify 9342 recent RIPs, and 8433 of these RIPs are novel compared with dbRIP, including 5826 Alu, 2169 long interspersed nuclear element 1 (L1), 383 SVA, and 55 long terminal repeats. Among the 9342 RIPs, 4828 were located in gene regions and 5 were located in protein-coding regions. We demonstrate that RIPs can, in principle, be an informative resource to perform population evolution and phylogenetic analyses. Taking the demographic effects into account, we identify a weak negative selection on SVA and L1 but an approximately neutral selection for Alu elements based on the frequency spectrum of RIPs. SID is a powerful open-source program for the detection of non-reference RIPs. We built a non-reference RIP dataset that greatly enhanced the diversity of RIPs detected in the general population, and it should be invaluable to researchers interested in many aspects of human evolution, genetics, and disease. As a proof of concept, we demonstrate that the RIPs can be used as biomarkers in a similar way as single nucleotide polymorphisms. © The Authors 2017. Published by Oxford University Press.
Rates and patterns of great ape retrotransposition
Hormozdiari, Fereydoun; Konkel, Miriam K.; Prado-Martinez, Javier; Chiatante, Giorgia; Herraez, Irene Hernando; Walker, Jerilyn A.; Nelson, Benjamin; Alkan, Can; Sudmant, Peter H.; Huddleston, John; Catacchio, Claudia R.; Ko, Arthur; Malig, Maika; Baker, Carl; Genome Project, Great Ape; Marques-Bonet, Tomas; Ventura, Mario; Batzer, Mark A.; Eichler, Evan E.
2013-01-01
We analyzed 83 fully sequenced great ape genomes for mobile element insertions, predicting a total of 49,452 fixed and polymorphic Alu and long interspersed element 1 (L1) insertions not present in the human reference assembly and assigning each retrotransposition event to a different time point during great ape evolution. We used these homoplasy-free markers to construct a mobile element insertions-based phylogeny of humans and great apes and demonstrate their differential power to discern ape subspecies and populations. Within this context, we find a good correlation between L1 diversity and single-nucleotide polymorphism heterozygosity (r2 = 0.65) in contrast to Alu repeats, which show little correlation (r2 = 0.07). We estimate that the “rate” of Alu retrotransposition has differed by a factor of 15-fold in these lineages. Humans, chimpanzees, and bonobos show the highest rates of Alu accumulation—the latter two since divergence 1.5 Mya. The L1 insertion rate, in contrast, has remained relatively constant, with rates differing by less than a factor of three. We conclude that Alu retrotransposition has been the most variable form of genetic variation during recent human–great ape evolution, with increases and decreases occurring over very short periods of evolutionary time. PMID:23884656
Delprat, Alejandra; Ruiz, Alfredo
2009-01-01
Background Transposable elements (TEs) are responsible for the generation of chromosomal inversions in several groups of organisms. However, in Drosophila and other Dipterans, where inversions are abundant both as intraspecific polymorphisms and interspecific fixed differences, the evidence for a role of TEs is scarce. Previous work revealed that the transposon Galileo was involved in the generation of two polymorphic inversions of Drosophila buzzatii. Methodology/Principal Findings To assess the impact of TEs in Drosophila chromosomal evolution and shed light on the mechanism involved, we isolated and sequenced the two breakpoints of another widespread polymorphic inversion from D. buzzatii, 2z 3. In the non inverted chromosome, the 2z 3 distal breakpoint was located between genes CG2046 and CG10326 whereas the proximal breakpoint lies between two novel genes that we have named Dlh and Mdp. In the inverted chromosome, the analysis of the breakpoint sequences revealed relatively large insertions (2,870-bp and 4,786-bp long) including two copies of the transposon Galileo (subfamily Newton), one at each breakpoint, plus several other TEs. The two Galileo copies: (i) are inserted in opposite orientation; (ii) present exchanged target site duplications; and (iii) are both chimeric. Conclusions/Significance Our observations provide the best evidence gathered so far for the role of TEs in the generation of Drosophila inversions. In addition, they show unequivocally that ectopic recombination is the causative mechanism. The fact that the three polymorphic D. buzzatii inversions investigated so far were generated by the same transposon family is remarkable and is conceivably due to Galileo's unusual structure and current (or recent) transpositional activity. PMID:19936241
Golubenko, M V; Puzyrev, V P; Saliukov, V B; Kucher, A N; Sanchat, N O
2000-03-01
Mitochondrial DNA region V deletion-insertion polymorphism was examined in three Tuvinian populations inhabiting western, northeastern, and southeastern parts of the republic. The 9-bp deletion was characterized by nonrandom distribution across the Tuva territory: its frequency in the western population (13.37%) was statistically significantly higher than that in the northeastern (4.62%), and southeastern populations, as well as in Mongols, who are territorially and ethnically close to Tuvinians. The insertion mutation in the region V was detected with a frequency of about 3% in two out of the three populations tested.
Identification of single nucleotide polymorphism in ginger using expressed sequence tags
Chandrasekar, Arumugam; Riju, Aikkal; Sithara, Kandiyl; Anoop, Sahadevan; Eapen, Santhosh J
2009-01-01
Ginger (Zingiber officinale Rosc) (Family: Zingiberaceae) is a herbaceous perennial, the rhizomes of which are used as a spice. Ginger is a plant which is well known for its medicinal applications. Recently EST-derived SNPs are a free by-product of the currently expanding EST (Expressed Sequence Tag) databases. The development of high-throughput methods for the detection of SNPs (Single Nucleotide Polymorphism) and small indels (insertion/deletion) has led to a revolution in their use as molecular markers. Available (38139) Ginger EST sequences were mined from dbEST of NCBI. CAP3 program was used to assemble EST sequences into contigs. Candidate SNPs and Indel polymorphisms were detected using the perl script AutoSNP version 1.0 which has used 31905 ESTs for detecting SNPs and Indel sites. We found 64026 SNP sites and 7034 indel polymorphisms with frequency of 0.84 SNPs / 100 bp. Among the three tissues from which the EST libraries had been generated, Rhizomes had high frequency of 1.08 SNPs/indels per 100 bp whereas the leaves had lowest frequency of 0.63 per 100 bp and root is showing relative frequency 0.82/100bp. Transitions and transversion ratio is 0.90. In overall detected SNP, transversion is high when compare to transition. These detected SNPs can be used as markers for genetic studies. Availability The results of the present study hosted in our webserver www.spices.res.in/spicesnip PMID:20198184
Negi, Vir S; Devaraju, Panneer; Gulati, Reena
2015-09-01
SLE is a systemic autoimmune disease with high prevalence of hypertension. Around 40-75 % of SLE patients develop nephritis, a major cause of hypertension and mortality. Angiotensin-converting enzyme (ACE) maintains the blood pressure and blood volume homeostasis. An insertion/deletion (I/D) polymorphism in intron 16 of ACE gene was reported to influence the development of hypertension, nephritis, and cardiovascular diseases in different ethnic populations. Despite compelling evidence for the high prevalence of hypertension in individuals with SLE, underlying factors for its development are not well studied. With this background, we analyzed the influence of ACE insertion/deletion polymorphism on susceptibility to SLE, development of nephritis and hypertension, other clinical features and autoantibody phenotype in South Indian SLE patients. Three hundred patients with SLE and 460 age and sex similar ethnicity matched individuals were included as patients and healthy controls, respectively. The ACE gene insertion/deletion polymorphism was analyzed by PCR. Insertion (I) and deletion (D) alleles were observed to be equally distributed among patients (57 and 43 %) and controls (59 and 41 %), respectively. The mutant (D) allele did not confer significant risk for SLE (II vs. ID: p = 0.4, OR 1.15, 95 % CI 0.8-1.6; II vs. DD: p = 0.34, OR 1.22, 95 % CI 0.8-1.85). There was no association of the ACE genotype or the allele with development of lupus nephritis (II vs. ID: p = 0.19, OR 1.41, 95 % CI 0.84-2.36; II vs. DD: p = 0.41, OR 0.74, 95 % CI 0.38-1.41) or hypertension (II vs. ID: p = 0.85, OR 0.9, 95 % CI 0.43-1.8; II vs. DD: p = 0.66, OR 1.217, 95 % CI 0.5-2.8). The presence of mutant allele (D) was not found to influence any clinical features or autoantibody phenotype. The insertion/deletion polymorphism of the ACE gene is not a genetic risk factor for SLE and does not influence development of hypertension or lupus nephritis in South Indian Tamils.
Djurisic, S; Teiblum, S; Tolstrup, C K; Christiansen, O B; Hviid, T V F
2015-03-01
The HLA-G molecule is expressed on trophoblast cells at the feto-maternal interface, where it interacts with local immune cells, and upholds tolerance against the semi-allogeneic fetus. Aberrant HLA-G expression in the placenta and reduced soluble HLA-G levels are observed in pregnancy complications, partly explained by HLA-G polymorphisms which are associated with differences in the alternative splicing pattern and of the stability of HLA-G mRNA. Of special importance is a 14 bp insertion/deletion polymorphism located in the 3'-untranslated region of the HLA-G gene. In the current study, we present novel evidence for allelic imbalance of the 14 bp insertion/deletion polymorphism, using a very accurate and sensitive Digital droplet PCR technique. Allelic imbalance in heterozygous samples was observed as differential expression levels of 14 bp insertion/deletion allele-specific mRNA transcripts, which was further associated with low levels of HLA-G surface expression on primary trophoblast cells. Full gene sequencing of HLA-G allowed us to study correlations between HLA-G extended haplotypes and single-nucleotide polymorphisms and HLA-G surface expression. We found that a 1:1 expression (allelic balance) of the 14 bp insertion/deletion mRNA alleles was associated with high surface expression of HLA-G and with a specific HLA-G extended haplotype. The 14 bp del/del genotype was associated with a significantly lower abundance of the G1 mRNA isoform, and a higher abundance of the G3 mRNA isoform. Overall, the present study provides original evidence for allelic imbalance of the 14 bp insertion/deletion polymorphism, which influences HLA-G surface expression on primary trophoblast cells, considered to be important in the pathogenesis of pre-eclampsia and other pregnancy complications. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Polymorphisms in the leptin gene promoter in Brazilian beef herds.
Guimarães, R C; Azevedo, J S N; Corrêa, S C; Campelo, J E G; Barbosa, E M; Gonçalves, E C; Silva Filho, E
2016-12-02
Brazil is the world's largest producer of beef cattle; however, the quality of its herds needs to be improved. The use of molecular markers as auxiliary tools in selecting animals for reproduction with high pattern for beef production would significantly improve the quality of the final beef product in Brazil. The leptin gene has been demonstrated to be an excellent candidate gene for bovine breeding. The objective of this study was to sequence and compare the leptin gene promoter of Brazil's important cattle breeds in order to identify polymorphisms in it. Blood samples of the Nellore, Guzerat, Tabapuã, and Senepol breeds were collected for genomic DNA extraction. The genomic DNA was used as a template for polymerase chain reaction (PCR) to amplify a 1575-bp fragment, which in turn was sequenced, aligned, and compared between animals of different breeds. Twenty-three single nucleotide polymorphic sites, including transitions and transversions, were detected at positions -1457, -1452, -1446, -1397, -1392, -1361, -1238, -963,-901, -578, -516, -483, -478, -470, -432, -430, -292, -282, -272, -211, -202, -170, and -147. Additionally, two insertion sites at positions -680 and -416 and two deletion sites at positions -1255 and -1059 were detected. As the promoter region of the leptin gene has been demonstrated to vary among breeds, these variations must be tested for their use as potential molecular markers for artificial selection of animals for enhanced beef production in different systems of bovine production in Brazil.
Pang, R; Li, Y; Dong, Y; Liang, Z; Zhang, Y; Zhang, W
2014-12-01
Imidacloprid resistance in the brown planthopper, Nilaparvata lugens, is primarily the result of the over-expression of cytochrome P450 monooxygenases. Here, a field-collected strain of N. lugens was shown to be highly resistant to both imidacloprid and buprofezin. Insecticide exposure and quantitative real-time PCR revealed that its resistance was mainly associated with a cytochrome P450 gene, CYP6AY1. CYP6AY1 is known to metabolize imidacloprid but its effect on buprofezin is unclear. In the 5'-untranslated region of CYP6AY1, a novel alternative splicing was detected. After a 1990-bp promoter region was cloned, its basal luciferase activity was assessed. Furthermore, genotyping studies identified 12 variations in the promoter region that discriminated between the field-collected and control strain. Finally, survival bioassays revealed a single nucleotide polymorphism and an insertion-deletion polymorphism linked to buprofezin and imidacloprid resistance. Mutagenesis of these sites enhanced the promoter activity of CYP6AY1. These results suggest that promoter polymorphisms may affect P450-mediated multiple insecticide resistance of pests. © 2014 The Royal Entomological Society.
Li, W J; Zhang, B; Huang, G W; Kang, G P; Liang, M Z; Chen, L B
2012-12-17
We analyzed chloroplast DNA (cpDNA) polymorphism and phylogenic relationships between 6 typical indica rice, 4 japonica rice, 8 javanica rice, and 12 Asian common wild rice (Oryza rufipogon) strains collected from different latitudes in China by comparing polymorphism at 9 highly variable regions. One hundred and forty-four polymorphic bases were detected. The O. rufipogon samples had 117 polymorphic bases, showing rich genetic diversity. One hundred and thirty-one bases at 13 sites were identified with indica/japonica characteristics; they showed differences between the indica and japonica subspecies at these sites. The javanica strains and japonica shared similar bases at these 131 polymorphic sites, suggesting that javanica is closely related to japonica. On the basis of length analyses of the open reading frame (ORF)100 and (ORF)29-tRNA-Cys(GCA) (TrnC(GCA)) fragments, the O. rufipogon strains were classified into indica/japonica subgroups, which was consistent with the results of the phylogenic tree assay based on concatenated datasets. These results indicated that differences in indica and japonica also exist in the cpDNA genome of the O. rufipogon strains. However, these differences demonstrated a certain degree of primitiveness and incompleteness, as an O. rufipogon line may show different indica/ japonica attributes at different sites. Consequently, O. rufipogon cannot be simply classified into the indica/japonica types as O. sativa. Our data support the hypothesis that Asian cultivated rice, O. indica and O. japonica, separately evolved from Asian common wild rice (O. rufipogon) strains, which have different indica-japonica differentiation trends.
Tetraploid Wheat Landraces in the Mediterranean Basin: Taxonomy, Evolution and Genetic Diversity
Oliveira, Hugo R.; Campana, Michael G.; Jones, Huw; Hunt, Harriet V.; Leigh, Fiona; Redhouse, David I.; Lister, Diane L.; Jones, Martin K.
2012-01-01
The geographic distribution of genetic diversity and the population structure of tetraploid wheat landraces in the Mediterranean basin has received relatively little attention. This is complicated by the lack of consensus concerning the taxonomy of tetraploid wheats and by unresolved questions regarding the domestication and spread of naked wheats. These knowledge gaps hinder crop diversity conservation efforts and plant breeding programmes. We investigated genetic diversity and population structure in tetraploid wheats (wild emmer, emmer, rivet and durum) using nuclear and chloroplast simple sequence repeats, functional variations and insertion site-based polymorphisms. Emmer and wild emmer constitute a genetically distinct population from durum and rivet, the latter seeming to share a common gene pool. Our population structure and genetic diversity data suggest a dynamic history of introduction and extinction of genotypes in the Mediterranean fields. PMID:22615891
ReadXplorer—visualization and analysis of mapped sequences
Hilker, Rolf; Stadermann, Kai Bernd; Doppmeier, Daniel; Kalinowski, Jörn; Stoye, Jens; Straube, Jasmin; Winnebald, Jörn; Goesmann, Alexander
2014-01-01
Motivation: Fast algorithms and well-arranged visualizations are required for the comprehensive analysis of the ever-growing size of genomic and transcriptomic next-generation sequencing data. Results: ReadXplorer is a software offering straightforward visualization and extensive analysis functions for genomic and transcriptomic DNA sequences mapped on a reference. A unique specialty of ReadXplorer is the quality classification of the read mappings. It is incorporated in all analysis functions and displayed in ReadXplorer's various synchronized data viewers for (i) the reference sequence, its base coverage as (ii) normalizable plot and (iii) histogram, (iv) read alignments and (v) read pairs. ReadXplorer's analysis capability covers RNA secondary structure prediction, single nucleotide polymorphism and deletion–insertion polymorphism detection, genomic feature and general coverage analysis. Especially for RNA-Seq data, it offers differential gene expression analysis, transcription start site and operon detection as well as RPKM value and read count calculations. Furthermore, ReadXplorer can combine or superimpose coverage of different datasets. Availability and implementation: ReadXplorer is available as open-source software at http://www.readxplorer.org along with a detailed manual. Contact: rhilker@mikrobio.med.uni-giessen.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:24790157
Konkel, Miriam K; Walker, Jerilyn A; Hotard, Ashley B; Ranck, Megan C; Fontenot, Catherine C; Storer, Jessica; Stewart, Chip; Marth, Gabor T; Batzer, Mark A
2015-08-29
The goal of the 1000 Genomes Consortium is to characterize human genome structural variation (SV), including forms of copy number variations such as deletions, duplications, and insertions. Mobile element insertions, particularly Alu elements, are major contributors to genomic SV among humans. During the pilot phase of the project we experimentally validated 645 (611 intergenic and 34 exon targeted) polymorphic "young" Alu insertion events, absent from the human reference genome. Here, we report high resolution sequencing of 343 (322 unique) recent Alu insertion events, along with their respective target site duplications, precise genomic breakpoint coordinates, subfamily assignment, percent divergence, and estimated A-rich tail lengths. All the sequenced Alu loci were derived from the AluY lineage with no evidence of retrotransposition activity involving older Alu families (e.g., AluJ and AluS). AluYa5 is currently the most active Alu subfamily in the human lineage, followed by AluYb8, and many others including three newly identified subfamilies we have termed AluYb7a3, AluYb8b1, and AluYa4a1. This report provides the structural details of 322 unique Alu variants from individual human genomes collectively adding about 100 kb of genomic variation. Many Alu subfamilies are currently active in human populations, including a surprising level of AluY retrotransposition. Human Alu subfamilies exhibit continuous evolution with potential drivers sprouting new Alu lineages. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Polymorphic site index curves for white pine in the southern Appalachians
Donald E. Beck
1971-01-01
Site index curves are presented for natural stands of even-aged white pine in the southern Appalachians. The curves are based on measured height-growth trends in 42 stands. Shape of the height-growth curves was shown to change progressively with the level of site index, and these polymorphic trends are incorporated in the finished site-index curves. Comparison of the...
Köppel, Herwig; Renner, Wilfried; Gugl, Alexander; Cichocki, Lisa; Gasser, Robert; Wascher, Thomas C; Pilger, Ernst
2004-01-01
The insertion/deletion (I/D) polymorphism of the gene for angiotensin-converting-enzyme (ACE) is associated with ACE plasma levels and activity. Conflicting results have been reported about the relevance of this polymorphism for venous thrombosis. The aim of the present study was to analyze the role of this polymorphism for deep venous thrombosis. The study was designed as a case-control study, including 330 patients with documented deep venous thrombosis and 354 controls. ACE genotype was determined by size-analysis of polymerase chain reaction products. Results showed that, ACE genotype frequencies were similar between patients (II: 24.8%; ID: 43.3%; DD: 31.8%) and controls (II: 22.9%; ID: 50.6%; DD: 26.6%, P = 0.15). The adjusted odds ratio of carriers of the DD geno-type for venous thrombosis was 1.24 (95% confidence interval 0.90-1.80). The polymorphism was furthermore not associated with age at first thromboembolic event or the occurrence of pulmonary embolism. From these results, we can conclude that the ACE I/D polymorphism is not a significant risk factor for deep venous thrombosis.
ACE insertion/deletion (I/D) polymorphism and diabetic nephropathy.
Rahimi, Zohreh
2012-10-01
Angiotensin converting enzyme (ACE) gene encodes ACE, a key component of renin angiotensin system (RAS), plays an important role in blood pressure homeostasis by generating the vasoconstrictor peptide angiotensin II. Directory of Open Access Journals (DOAJ), Google Scholar, Pubmed (NLM), LISTA (EBSCO) and Web of Science have been searched. The presence of ACE insertion/deletion (I/D) polymorphism affects the plasma level of ACE. ACE DD genotype is associated with the highest systemic and renal ACE levels compared with the lowest ACE activity in carriers of II genotype. In this review focus has been performed on the study of ACE I/D polymorphism in various populations and its influence on the risk of onset and progression of diabetic nephropathy. Also, association between ACE I/D polymorphism and response to ACE inhibitor and angiotensin II receptor antagonists will be reviewed. Further, synergistic effect of this polymorphism and variants of some genes on the risk of development of diabetic nephropathy will be discussed.
Sistiaga-Poveda, M; Jugo, B M
2014-06-01
The oncogenic exogenous Jaagsiekte sheep retrovirus (JSRV), responsible for ovine pulmonary adenocarcinoma, has several endogenous counterparts termed enJSRVs. Although many of these elements have been inactivated over time by the accumulation of deleterious mutations or internal recombination leading to solo long terminal repeat (LTR) formation, several members of enJSRVs have been identified as nearly intact and probably represent recent integration events. To determine the level of enJSRV polymorphism in the sheep population and related species, we have undertaken a study by characterizing enJSRVs copies and independent integration sites in six domestic sheep and two wild species of the sheep lineage. enJSRVs copies were detected by amplifying the env-LTR region by PCR, and for the detection of the insertion sites, we used two approaches: (1) an in silico approach based on the recently published Sheep Reference Genome Assembly (OARv3.0) and (2) an experimental approach based on PCR suppression and inverse PCR techniques. In total, 103 enJSRV sequences were generated across 10 individuals and enJSRV integrations were found on 11 of the 28 sheep chromosomes. These findings suggest that there are still uncharacterized enJSRVs, and that some of the integration sites are variable among the different species, breeds of the same species, subspecies and geographic locations.
Detection of possible restriction sites for type II restriction enzymes in DNA sequences.
Gagniuc, P; Cimponeriu, D; Ionescu-Tîrgovişte, C; Mihai, Andrada; Stavarachi, Monica; Mihai, T; Gavrilă, L
2011-01-01
In order to make a step forward in the knowledge of the mechanism operating in complex polygenic disorders such as diabetes and obesity, this paper proposes a new algorithm (PRSD -possible restriction site detection) and its implementation in Applied Genetics software. This software can be used for in silico detection of potential (hidden) recognition sites for endonucleases and for nucleotide repeats identification. The recognition sites for endonucleases may result from hidden sequences through deletion or insertion of a specific number of nucleotides. Tests were conducted on DNA sequences downloaded from NCBI servers using specific recognition sites for common type II restriction enzymes introduced in the software database (n = 126). Each possible recognition site indicated by the PRSD algorithm implemented in Applied Genetics was checked and confirmed by NEBcutter V2.0 and Webcutter 2.0 software. In the sequence NG_008724.1 (which includes 63632 nucleotides) we found a high number of potential restriction sites for ECO R1 that may be produced by deletion (n = 43 sites) or insertion (n = 591 sites) of one nucleotide. The second module of Applied Genetics has been designed to find simple repeats sizes with a real future in understanding the role of SNPs (Single Nucleotide Polymorphisms) in the pathogenesis of the complex metabolic disorders. We have tested the presence of simple repetitive sequences in five DNA sequence. The software indicated exact position of each repeats detected in the tested sequences. Future development of Applied Genetics can provide an alternative for powerful tools used to search for restriction sites or repetitive sequences or to improve genotyping methods.
Hernández-Martínez, Miguel Ángel; Escalante, Ananías A.; Arévalo-Herrera, Myriam; Herrera, Sócrates
2011-01-01
Circumsporozoite (CS) protein is a malaria antigen involved in sporozoite invasion of hepatocytes, and thus considered to have good vaccine potential. We evaluated the polymorphism of the Plasmodium vivax CS gene in 24 parasite isolates collected from malaria-endemic areas of Colombia. We sequenced 27 alleles, most of which (25/27) corresponded to the VK247 genotype and the remainder to the VK210 type. All VK247 alleles presented a mutation (Gly → Asn) at position 28 in the N-terminal region, whereas the C-terminal presented three insertions: the ANKKAGDAG, which is common in all VK247 isolates; 12 alleles presented the insertion GAGGQAAGGNAANKKAGDAG; and 5 alleles presented the insertion GGNAGGNA. Both repeat regions were polymorphic in gene sequence and size. Sequences coding for B-, T-CD4+, and T-CD8+ cell epitopes were found to be conserved. This study confirms the high polymorphism of the repeat domain and the highly conserved nature of the flanking regions. PMID:21292878
Wang, J; Yang, S; Guo, F H; Mao, X; Zhou, H; Dong, Y Q; Wang, Z M; Luo, F
2015-11-13
The angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism has been reported to be associated with digestive system cancer; however, the results from previous studies have been conflicting. The present study aimed to investigate the association between the ACE I/D polymorphism and the risk of digestive system cancer using a meta-analysis of previously published studies. Databases were systematically searched to identify relevant studies published prior to December 2014. We estimated the pooled OR with its 95%CI to assess the association. The meta-analysis consisted of thirteen case-control studies that included 2557 patients and 4356 healthy controls. Meta-analysis results based on all the studies showed no significant association between the ACE I/D polymorphism and the risk of digestive system cancer (DD vs II: OR = 0.85, 95%CI = 0.59-1.24; DI vs II: OR = 0.94, 95%CI = 0.78-1.15; dominant model: OR = 0.96, 95%CI = 0.81- 1.15; recessive model: OR = 1.06, 95%CI = 0.76-1.48). Subgroup analyses by race and cancer type did not detect an association between the ACE I/D polymorphism and digestive system cancer risk. However, when the analyses were restricted to smaller studies (N < 500 patients), the summary OR of DI vs II was 0.80 (95%CI = 0.66-0.97). Our analyses detected a possibility of publication bias with a misestimate of the true association by smaller studies. Overall, meta-analysis results suggest the ACE I/D polymorphism might not be associated with susceptibility to digestive system cancer. Further large and well-designed studies are needed to confirm these conclusions.
A meta-analysis of eNOS and ACE gene polymorphisms and risk of pre-eclampsia in women.
Shaik, A P; Sultana, A; Bammidi, V K; Sampathirao, K; Jamil, K
2011-10-01
A meta-analyses of endothelial nitric oxide synthase (eNOS) and angiotensin-converting enzyme (ACE) gene polymorphisms in pre-eclampsia was performed. We shortlisted 33 studies (17 for ACE; 16 for eNOS gene polymorphisms), of which 29 articles (16 for ACE and 15 for eNOS) were analysed. Overall, 1,620 cases with pre-eclampsia and 2,158 controls were analysed for intron 16 insertion-deletion polymorphism in ACE gene. A total of 1,610 subjects with pre-eclampsia and 2,875 controls were analysed for the Glu298Asp in eNOS gene. Overall, the random-effects odds ratio (OR) with Glu298Asp in eNOS gene was 0.958 (95% confidence intervals, CI 0.747-1.228, p > 0.05), and for the insertion-deletion/ACE polymorphism was 0.987 (95% CI 0.698-1.395, p > 0.05). Significant heterogeneity was observed in the studies that evaluated polymorphisms in ACE (Q value = 55.6; I(2) = 73; p value = 0.000); and eNOS (Q value = 37.2; I(2) = 62.4; p value = 0.001) polymorphisms. No significant risk of pre-eclampsia was observed in both eNOS and ACE genes with these polymorphisms.
Insertional Polymorphisms of Endogenous Feline Leukemia Viruses
Roca, Alfred L.; Nash, William G.; Menninger, Joan C.; Murphy, William J.; O'Brien, Stephen J.
2005-01-01
The number, chromosomal distribution, and insertional polymorphisms of endogenous feline leukemia viruses (enFeLVs) were determined in four domestic cats (Burmese, Egyptian Mau, Persian, and nonbreed) using fluorescent in situ hybridization and radiation hybrid mapping. Twenty-nine distinct enFeLV loci were detected across 12 of the 18 autosomes. Each cat carried enFeLV at only 9 to 16 of the loci, and many loci were heterozygous for presence of the provirus. Thus, an average of 19 autosomal copies of enFeLV were present per cat diploid genome. Only five of the autosomal enFeLV sites were present in all four cats, and at only one autosomal locus, B4q15, was enFeLV present in both homologues of all four cats. A single enFeLV occurred in the X chromosome of the Burmese cat, while three to five enFeLV proviruses occurred in each Y chromosome. The X chromosome and nine autosomal enFeLV loci were telomeric, suggesting that ectopic recombination between nonhomologous subtelomeres may contribute to enFeLV distribution. Since endogenous FeLVs may affect the infectiousness or pathogenicity of exogenous FeLVs, genomic variation in enFeLVs represents a candidate for genetic influences on FeLV leukemogenesis in cats. PMID:15767400
Sakai, Hiroaki; Kanamori, Hiroyuki; Arai-Kichise, Yuko; Shibata-Hatta, Mari; Ebana, Kaworu; Oono, Youko; Kurita, Kanako; Fujisawa, Hiroko; Katagiri, Satoshi; Mukai, Yoshiyuki; Hamada, Masao; Itoh, Takeshi; Matsumoto, Takashi; Katayose, Yuichi; Wakasa, Kyo; Yano, Masahiro; Wu, Jianzhong
2014-01-01
Having a deep genetic structure evolved during its domestication and adaptation, the Asian cultivated rice (Oryza sativa) displays considerable physiological and morphological variations. Here, we describe deep whole-genome sequencing of the aus rice cultivar Kasalath by using the advanced next-generation sequencing (NGS) technologies to gain a better understanding of the sequence and structural changes among highly differentiated cultivars. The de novo assembled Kasalath sequences represented 91.1% (330.55 Mb) of the genome and contained 35 139 expressed loci annotated by RNA-Seq analysis. We detected 2 787 250 single-nucleotide polymorphisms (SNPs) and 7393 large insertion/deletion (indel) sites (>100 bp) between Kasalath and Nipponbare, and 2 216 251 SNPs and 3780 large indels between Kasalath and 93-11. Extensive comparison of the gene contents among these cultivars revealed similar rates of gene gain and loss. We detected at least 7.39 Mb of inserted sequences and 40.75 Mb of unmapped sequences in the Kasalath genome in comparison with the Nipponbare reference genome. Mapping of the publicly available NGS short reads from 50 rice accessions proved the necessity and the value of using the Kasalath whole-genome sequence as an additional reference to capture the sequence polymorphisms that cannot be discovered by using the Nipponbare sequence alone. PMID:24578372
Alu polymorphic insertions reveal genetic structure of north Indian populations.
Tripathi, Manorama; Tripathi, Piyush; Chauhan, Ugam Kumari; Herrera, Rene J; Agrawal, Suraksha
2008-10-01
The Indian subcontinent is characterized by the ancestral and cultural diversity of its people. Genetic input from several unique source populations and from the unique social architecture provided by the caste system has shaped the current genetic landscape of India. In the present study 200 individuals each from three upper-caste and four middle-caste Hindu groups and from two Muslim populations in North India were examined for 10 polymorphic Alu insertions (PAIs). The investigated PAIs exhibit high levels of polymorphism and average heterozygosity. Limited interpopulation variance and genetic flow in the present study suggest admixture. The results of this study demonstrate that, contrary to common belief, the caste system has not provided an impermeable barrier to genetic exchange among Indian groups.
Hahntow, Ines N; Mairuhu, Gideon; van Valkengoed, Irene Gm; Koopmans, Richard P; Michel, Martin C
2010-06-02
Genotype-phenotype association studies are typically based upon polymorphisms or haplotypes comprised of multiple polymorphisms within a single gene. It has been proposed that combinations of polymorphisms in distinct genes, which functionally impact the same phenotype, may have stronger phenotype associations than those within a single gene. We have tested this hypothesis using genes encoding components of the renin-angiotensin-aldosterone system and the high blood pressure phenotype. Our analysis is based on 1379 participants of the cross-sectional SUNSET study randomly selected from the population register of Amsterdam. Each subject was genotyped for the angiotensinogen M235T, the angiotensin-converting enzyme insertion/deletion and the angiotensin II type 1 receptor A1166C polymorphism. The phenotype high blood pressure was defined either as a categorical variable comparing hypertension versus normotension as in most previous studies or as a continuous variable using systolic, diastolic and mean blood pressure in a multiple regression analysis with gender, ethnicity, age, body-mass-index and antihypertensive medication as covariates. Genotype-phenotype relationships were explored for each polymorphism in isolation and for double and triple polymorphism combinations. At the single polymorphism level, only the A allele of the angiotensin II type 1 receptor was associated with a high blood pressure phenotype. Using combinations of polymorphisms of two or all three genes did not yield stronger/more consistent associations. We conclude that combinations of physiologically related polymorphisms of multiple genes, at least with regard to the renin-angiotensin-aldosterone system and the hypertensive phenotype, do not necessarily offer additional benefit in analyzing genotype/phenotype associations.
Mastan, Shaik G; Rathore, Mangal S; Bhatt, Vacha D; Chikara, J; Ghosh, A
2014-12-01
We investigated DNA methylation and polymorphism in the methylated DNA using AFLP based methylation-sensitive amplification polymorphism (MS-AFLP) markers in ecotypes of Jatropha curcas L. growing in similar and different geo-ecological conditions. Three ecotypes growing in different geo-ecological conditions with environmental heterogeneity (Group-1) and five ecotypes growing in similar environmental conditions (Group-2) were assessed. In ecotypes growing in group-1, 44.32 % DNA was methylated and of which 93.59 % DNA was polymorphic. While in group-2, 32.27 % DNA was methylated, of which 51.64 % DNA was polymorphic. In site 1 and site 2 of group-1, overall methylation was 18.94 and 22.44 % respectively with difference of 3.5 %, while overall polymorphism was 41.14 and 39.23 % with a difference of 1.91 %. In site 1 and site 2 of group-2, overall methylation was 24.68 and 24.18 % respectively with difference of 0.5 %, while overall polymorphism was 12.19 and 12.65 % with a difference of 0.46 %. The difference of methylation percentage and percentage of methylation polymorphism throughout the genome of J. curcas at site 1 and 2 of group-1 is higher than that of J. curcas at site 1 and 2 of group-2. These results correlated the physico-chemical properties of soil at these sites. The variations of physico-chemical properties of soil at Chorwadla (site 1 in group-1 and site 2 in group-2) compared to the soil at Brahmapur (site 2 in group-1) is higher than that of soil at Neswad (site 1 in group-2). The study suggests that these homologous nucleotide sequences probably play important role in ecotype adaptation to environmental heterogeneity by creating epiallelic variations hence in evolution of ecotypes/clines or forms of species showing phenotypic/genotypic differences in different geographical areas.
Ferreira, Keila Adriana Magalhães; Fajardo, Emanuella Francisco; Baptista, Rodrigo P; Macedo, Andrea Mara; Lages-Silva, Eliane; Ramírez, Luis Eduardo; Pedrosa, André Luiz
2014-06-01
Trypanosoma cruzi and Trypanosoma rangeli are kinetoplastid parasites which are able to infect humans in Central and South America. Misdiagnosis between these trypanosomes can be avoided by targeting barcoding sequences or genes of each organism. This work aims to analyze the feasibility of using species-specific markers for identification of intraspecific polymorphisms and as target for diagnostic methods by PCR. Accordingly, primers which are able to specifically detect T. cruzi or T. rangeli genomic DNA were characterized. The use of intergenic regions, generally divergent in the trypanosomatids, and the serine carboxypeptidase gene were successful. Using T. rangeli genomic sequences for the identification of group-specific polymorphisms and a polymorphic AT(n) dinucleotide repeat permitted the classification of the strains into two groups, which are entirely coincident with T. rangeli main lineages, KP1 (+) and KP1 (-), previously determined by kinetoplast DNA (kDNA) characterization. The sequences analyzed totalize 622 bp (382 bp represent a hypothetical protein sequence, and 240 bp represent an anonymous sequence), and of these, 581 (93.3%) are conserved sites and 41 bp (6.7%) are polymorphic, with 9 transitions (21.9%), 2 transversions (4.9%), and 30 (73.2%) insertion/deletion events. Taken together, the species-specific markers analyzed may be useful for the development of new strategies for the accurate diagnosis of infections. Furthermore, the identification of T. rangeli polymorphisms has a direct impact in the understanding of the population structure of this parasite.
Concealed Accessory Pathways with a Single Ventricular and Two Discrete Atrial Insertion Sites.
Kipp, Ryan T; Abu Sham'a, Raed; Hiroyuki, Ito; Han, Frederick T; Refaat, Marwan; Hsu, Jonathan C; Field, Michael E; Kopp, Douglas E; Marcus, Gregory M; Scheinman, Melvin M; Hoffmayer, Kurt S
2017-03-01
Atrioventricular reciprocating tachycardia (AVRT) utilizing a concealed accessory pathway is common. It is well appreciated that some patients may have multiple accessory pathways with separate atrial and ventricular insertion sites. We present three cases of AVRT utilizing concealed pathways with evidence that each utilizing a single ventricular insertion and two discrete atrial insertion sites. In case one, two discrete atrial insertion sites were mapped in two separate procedures, and only during the second ablation was the Kent potential identified. Ablation of the Kent potential at this site remote from the two atrial insertion sites resulted in the termination of the retrograde conduction in both pathways. Case two presented with supraventricular tachycardia (SVT) with alternating eccentric atrial activation patterns without alteration in the tachycardia cycle length. The two distinct atrial insertion sites during orthodromic AVRT and ventricular pacing were targeted and each of the two atrial insertion sites were successfully mapped and ablated. In case three, retrograde decremental conduction utilizing both atrial insertion sites was identified prior to ablation. After mapping and ablation of the first discrete atrial insertion site, tachycardia persisted utilizing the second atrial insertion site. Only after ablation of the second atrial insertion site was SVT noninducible, and VA conduction was no longer present. Concealed retrograde accessory pathways with discrete atrial insertion sites may have a common ventricular insertion site. Identification and ablation of the ventricular insertion site or the separate discrete atrial insertion sites result in successful treatment. © 2017 Wiley Periodicals, Inc.
Diversity and structure of PIF/Harbinger-like elements in the genome of Medicago truncatula
Grzebelus, Dariusz; Lasota, Slawomir; Gambin, Tomasz; Kucherov, Gregory; Gambin, Anna
2007-01-01
Background Transposable elements constitute a significant fraction of plant genomes. The PIF/Harbinger superfamily includes DNA transposons (class II elements) carrying terminal inverted repeats and producing a 3 bp target site duplication upon insertion. The presence of an ORF coding for the DDE/DDD transposase, required for transposition, is characteristic for the autonomous PIF/Harbinger-like elements. Based on the above features, PIF/Harbinger-like elements were identified in several plant genomes and divided into several evolutionary lineages. Availability of a significant portion of Medicago truncatula genomic sequence allowed for mining PIF/Harbinger-like elements, starting from a single previously described element MtMaster. Results Twenty two putative autonomous, i.e. carrying an ORF coding for TPase and complete terminal inverted repeats, and 67 non-autonomous PIF/Harbinger-like elements were found in the genome of M. truncatula. They were divided into five families, MtPH-A5, MtPH-A6, MtPH-D,MtPH-E, and MtPH-M, corresponding to three previously identified and two new lineages. The largest families, MtPH-A6 and MtPH-M were further divided into four and three subfamilies, respectively. Non-autonomous elements were usually direct deletion derivatives of the putative autonomous element, however other types of rearrangements, including inversions and nested insertions were also observed. An interesting structural characteristic – the presence of 60 bp tandem repeats – was observed in a group of elements of subfamily MtPH-A6-4. Some families could be related to miniature inverted repeat elements (MITEs). The presence of empty loci (RESites), paralogous to those flanking the identified transposable elements, both autonomous and non-autonomous, as well as the presence of transposon insertion related size polymorphisms, confirmed that some of the mined elements were capable for transposition. Conclusion The population of PIF/Harbinger-like elements in the genome of M. truncatula is diverse. A detailed intra-family comparison of the elements' structure proved that they proliferated in the genome generally following the model of abortive gap repair. However, the presence of tandem repeats facilitated more pronounced rearrangements of the element internal regions. The insertion polymorphism of the MtPH elements and related MITE families in different populations of M. truncatula, if further confirmed experimentally, could be used as a source of molecular markers complementary to other marker systems. PMID:17996080
Rogan, P K; Schneider, T D
1995-01-01
Predicting the effects of nucleotide substitutions in human splice sites has been based on analysis of consensus sequences. We used a graphic representation of sequence conservation and base frequency, the sequence logo, to demonstrate that a change in a splice acceptor of hMSH2 (a gene associated with familial nonpolyposis colon cancer) probably does not reduce splicing efficiency. This confirms a population genetic study that suggested that this substitution is a genetic polymorphism. The information theory-based sequence logo is quantitative and more sensitive than the corresponding splice acceptor consensus sequence for detection of true mutations. Information analysis may potentially be used to distinguish polymorphisms from mutations in other types of transcriptional, translational, or protein-coding motifs.
Novel Tay-Sachs disease mutations from China.
Akalin, N; Shi, H P; Vavougios, G; Hechtman, P; Lo, W; Scriver, C R; Mahuran, D; Kaplan, F
1992-01-01
We describe three HEXA mutations associated with infantile Tay-Sachs disease (TSD) in three unrelated nonconsanguineous Chinese families. Novel mutations were found in two of these families. The third is a previously reported mutation (G-->A transition at nt 1444) (Nakano et al., 1988). Direct sequencing of PCR products identified a novel insertion of an A after nt 547 in family 1. This change generates an early termination codon 6 bp downstream from the insertion site. Allele-specific oligonucleotide hybridization confirmed homozygosity in the proband. Single strand conformational polymorphism analysis and direct sequencing of amplified exon 13 revealed a T-->C transition at nt 1453 with the corresponding amino acid substitution W485R in the second family. This mutation creates an Fnu4HI restriction site. The proband is homozygous for this allele. When the site-specific mutagenized alpha cDNA carrying the T-->C transition at nt 1453 was expressed in COS 1 cells hexosaminidase S activity was not detectable above background. A G-->A transition at nt 1444 (exon 13) corresponding to the E482K substitution was found in the third family. This mutation occurs at a CpG dinucleotide. It has been reported in an Italian TSD proband and causes defective intracellular transport of the alpha-subunit from the rough endoplasmic reticulum to the Golgi apparatus.
Mobile elements reveal small population size in the ancient ancestors of Homo sapiens.
Huff, Chad D; Xing, Jinchuan; Rogers, Alan R; Witherspoon, David; Jorde, Lynn B
2010-02-02
The genealogies of different genetic loci vary in depth. The deeper the genealogy, the greater the chance that it will include a rare event, such as the insertion of a mobile element. Therefore, the genealogy of a region that contains a mobile element is on average older than that of the rest of the genome. In a simple demographic model, the expected time to most recent common ancestor (TMRCA) is doubled if a rare insertion is present. We test this expectation by examining single nucleotide polymorphisms around polymorphic Alu insertions from two completely sequenced human genomes. The estimated TMRCA for regions containing a polymorphic insertion is two times larger than the genomic average (P < <10(-30)), as predicted. Because genealogies that contain polymorphic mobile elements are old, they are shaped largely by the forces of ancient population history and are insensitive to recent demographic events, such as bottlenecks and expansions. Remarkably, the information in just two human DNA sequences provides substantial information about ancient human population size. By comparing the likelihood of various demographic models, we estimate that the effective population size of human ancestors living before 1.2 million years ago was 18,500, and we can reject all models where the ancient effective population size was larger than 26,000. This result implies an unusually small population for a species spread across the entire Old World, particularly in light of the effective population sizes of chimpanzees (21,000) and gorillas (25,000), which each inhabit only one part of a single continent.
Lithiation Thermodynamics and Kinetics of the TiO 2 (B) Nanoparticles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hua, Xiao; Liu, Zheng; Fischer, Michael G.
TiO2 (B) has attracted a lot of attention in recent years because it exhibits the largest capacity among all studied titania polymorphs with high rate performance for Li intercalation achieved when this material is nanostructured. However, due to the complex nature of its lithiation mechanism and practical challenges in probing Li local environments in nanostructured materials, a definitive understanding of the lithiation thermodynamics has yet to be established. A comprehensive mechanistic investigation of the TiO2 (B) nanoparticles is therefore presented using a combination of in situ / operando X-ray pair distribution function (PDF) and electrochemical techniques. The discharge begins withmore » surface reactions involving surface hydroxyl groups. Such reactions contribute to the capacity loss and take place in parallel with Li insertion into the near-surface region of the nanoparticles. The Li bulk insertion starts with a single-phase reaction into the A2 site, a position adjacent to the b channel. A change of the Li diffusion pathway from that along this open channel to that along the c-direction is likely to occur at the composition of Li0.25TiO2 until Li0.5TiO2 is attained, leading to a two-step A2-site incorporation with one step kinetically distinct from the other. Subsequent Li insertion involves C’ site, a position situated inside the channel, and follows a rapid two-phase reaction to form Li0.75TiO2. Due to the high diffusion barrier associated with the further lithiation, Li insertion into the A1 site, another position adjacent to the channel neighboring the A2 sites, is kinetically restricted. It can be promoted by either nanostructuring or raising the operating temperature, the latter however triggering concurrent electrolyte decomposition giving rise to additional capacity loss. This study not only provides compelling experimental evidence for the unresolved reaction thermodynamics of nanoparticulate TiO2 (B), but also serves as a strong reference for future studies of the bulk phase, and for future calculations to study the kinetic properties of TiO2 (B).« less
Dettenkofer, M; Jonas, D; Wiechmann, C; Rossner, R; Frank, U; Zentner, J; Daschner, F D
2002-10-01
We investigated the efficacy of two commercially available, alcohol-based antiseptic solutions in decontaminating the insertion site of central lines. One solution contained the bispyridine octenidine dihydrochloride. Inpatients receiving either a central venous catheter (CVC) or a peripherally inserted central catheter (PICC) were alternately assigned to different skin disinfection regimens at the insertion site: (A) 0.1% octendine dihydrochloride with 30% 1-propanol and 45% 2-propanol, (B) 74% ethanol with 10% 2-propanol. Quantitative skin cultures were obtained from the insertion site at predetermined intervals. A total of 60 patients received 12 CVCs and 47 PICCs (no significant difference with respect to gender, age and catheter type). In total, 90 cultures were assessed in each group. The median colony-forming unit (cfu) counts per 24 cm(2) (group A vs B) were 2,270 vs 2,950 before, 20 vs 40 following and 860 vs 1,210 24 h after catheter insertion, respectively. A statistically significant difference in the efficacy of skin decontamination was seen between groups in culture set (3) and in the difference between culture sets (2) and (3) (Wilcoxon rank sum test). Octenidine/propanol appears to be more effective than alcohol (ethanol/propanol) alone in reducing microflora of the skin at the PICC/CVC insertion site over a 24-h period.
Kothapalli, Kumar S. D.; Ye, , Kaixiong; Gadgil, Maithili S.; Carlson, Susan E.; O’Brien, Kimberly O.; Zhang, Ji Yao; Park, Hui Gyu; Ojukwu, Kinsley; Zou, James; Hyon, Stephanie S.; Joshi, Kalpana S.; Gu, Zhenglong; Keinan, Alon; Brenna, J.Thomas
2016-01-01
Long chain polyunsaturated fatty acids (LCPUFA) are bioactive components of membrane phospholipids and serve as substrates for signaling molecules. LCPUFA can be obtained directly from animal foods or synthesized endogenously from 18 carbon precursors via the FADS2 coded enzyme. Vegans rely almost exclusively on endogenous synthesis to generate LCPUFA and we hypothesized that an adaptive genetic polymorphism would confer advantage. The rs66698963 polymorphism, a 22-bp insertion–deletion within FADS2, is associated with basal FADS1 expression, and coordinated induction of FADS1 and FADS2 in vitro. Here, we determined rs66698963 genotype frequencies from 234 individuals of a primarily vegetarian Indian population and 311 individuals from the US. A much higher I/I genotype frequency was found in Indians (68%) than in the US (18%). Analysis using 1000 Genomes Project data confirmed our observation, revealing a global I/I genotype of 70% in South Asians, 53% in Africans, 29% in East Asians, and 17% in Europeans. Tests based on population divergence, site frequency spectrum, and long-range haplotype consistently point to positive selection encompassing rs66698963 in South Asian, African, and some East Asian populations. Basal plasma phospholipid arachidonic acid (ARA) status was 8% greater in I/I compared with D/D individuals. The biochemical pathway product–precursor difference, ARA minus linoleic acid, was 31% and 13% greater for I/I and I/D compared with D/D, respectively. This study is consistent with previous in vitro data suggesting that the insertion allele enhances n-6 LCPUFA synthesis and may confer an adaptive advantage in South Asians because of the traditional plant-based diet practice. PMID:27188529
Hong, S H; Kang, B Y; Park, W H; Kim, J Q; Lee, C C
1997-01-01
In view of the clinical importance of angiotensin-converting enzyme (ACE) as a major marker for cardiovascular diseases, we investigated insertion/deletion (I/D) polymorphism of the ACE gene in Koreans. Genotype frequencies were examined by polymerase chain reaction in 171 patients with coronary artery disease (CAD) and 120 healthy subjects. Allele frequencies of ACE polymorphism in Koreans were not significantly different between patient and control groups. In addition, association between ACE genotypes and the number of stenosed coronary arteries was not detected. ACE genotypes in the CAD group were not associated with body mass index and plasma lipid levels. Thus, our results suggest that, at least in Koreans, I/D polymorphism of the gene is unlikely to be a useful marker for CAD subjects. However, the I allele frequency of Koreans (0.58) was higher than that of Caucasian populations (0.47) but lower than that of Samoan (0.91) and Yanomami (0.85) populations. Here, we discuss the clinical and ethnic importance of ACE polymorphism.
Molecular Population Genetics of the Alcohol Dehydrogenase Gene Region of DROSOPHILA MELANOGASTER
Aquadro, Charles F.; Desse, Susan F.; Bland, Molly M.; Langley, Charles H.; Laurie-Ahlberg, Cathy C.
1986-01-01
Variation in the DNA restriction map of a 13-kb region of chromosome II including the alcohol dehydrogenase structural gene (Adh) was examined in Drosophila melanogaster from natural populations. Detailed analysis of 48 D. melanogaster lines representing four eastern United States populations revealed extensive DNA sequence variation due to base substitutions, insertions and deletions. Cloning of this region from several lines allowed characterization of length variation as due to unique sequence insertions or deletions [nine sizes; 21–200 base pairs (bp)] or transposable element insertions (several sizes, 340 bp to 10.2 kb, representing four different elements). Despite this extensive variation in sequences flanking the Adh gene, only one length polymorphism is clearly associated with altered Adh expression (a copia element approximately 250 bp 5' to the distal transcript start site). Nonetheless, the frequency spectra of transposable elements within and between Drosophila species suggests they are slightly deleterious. Strong nonrandom associations are observed among Adh region sequence variants, ADH allozyme (Fast vs. Slow), ADH enzyme activity and the chromosome inversion ln(2L) t. Phylogenetic analysis of restriction map haplotypes suggest that the major twofold component of ADH activity variation (high vs. low, typical of Fast and Slow allozymes, respectively) is due to sequence variation tightly linked to and possibly distinct from that underlying the allozyme difference. The patterns of nucleotide and haplotype variation for Fast and Slow allozyme lines are consistent with the recent increase in frequency and spread of the Fast haplotype associated with high ADH activity. These data emphasize the important role of evolutionary history and strong nonrandom associations among tightly linked sequence variation as determinants of the patterns of variation observed in natural populations. PMID:3026893
USDA-ARS?s Scientific Manuscript database
Mycoplasma bovis is an important cause of disease in cattle and bison. Because the bacterium requires specialized growth conditions many diagnostic laboratories routinely use PCR to replace or complement conventional isolation and identification methods. A frequently used target of such assays is th...
Mobile Interspersed Repeats Are Major Structural Variants in the Human Genome
Huang, Cheng Ran Lisa; Schneider, Anna M.; Lu, Yunqi; Niranjan, Tejasvi; Shen, Peilin; Robinson, Matoya A.; Steranka, Jared P.; Valle, David; Civin, Curt I.; Wang, Tao; Wheelan, Sarah J.; Ji, Hongkai; Boeke, Jef D.; Burns, Kathleen H.
2010-01-01
Summary Characterizing structural variants in the human genome is of great importance, but a genome wide analysis to detect interspersed repeats has not been done. Thus, the degree to which mobile DNAs contribute to genetic diversity, heritable disease, and oncogenesis remains speculative. We perform transposon insertion profiling by microarray (TIP-chip) to map human L1(Ta) retrotransposons (LINE-1 s) genome-wide. This identified numerous novel human L1(Ta) insertional polymorphisms with highly variant allelic frequencies. We also explored TIP-chip's usefulness to identify candidate alleles associated with different phenotypes in clinical cohorts. Our data suggest that the occurrence of new insertions is twice as high as previously estimated, and that these repeats are under-recognized as sources of human genomic and phenotypic diversity. We have just begun to probe the universe of human L1(Ta) polymorphisms, and as TIP-chip is applied to other insertions such as Alu SINEs, it will expand the catalog of genomic variants even further. PMID:20602999
Sistiaga-Poveda, M; Jugo, B M
2014-01-01
The oncogenic exogenous Jaagsiekte sheep retrovirus (JSRV), responsible for ovine pulmonary adenocarcinoma, has several endogenous counterparts termed enJSRVs. Although many of these elements have been inactivated over time by the accumulation of deleterious mutations or internal recombination leading to solo long terminal repeat (LTR) formation, several members of enJSRVs have been identified as nearly intact and probably represent recent integration events. To determine the level of enJSRV polymorphism in the sheep population and related species, we have undertaken a study by characterizing enJSRVs copies and independent integration sites in six domestic sheep and two wild species of the sheep lineage. enJSRVs copies were detected by amplifying the env-LTR region by PCR, and for the detection of the insertion sites, we used two approaches: (1) an in silico approach based on the recently published Sheep Reference Genome Assembly (OARv3.0) and (2) an experimental approach based on PCR suppression and inverse PCR techniques. In total, 103 enJSRV sequences were generated across 10 individuals and enJSRV integrations were found on 11 of the 28 sheep chromosomes. These findings suggest that there are still uncharacterized enJSRVs, and that some of the integration sites are variable among the different species, breeds of the same species, subspecies and geographic locations. PMID:24690757
Comparative analysis of myostatin gene and promoter sequences of Qinchuan and Red Angus cattle.
He, Y L; Wu, Y H; Quan, F S; Liu, Y G; Zhang, Y
2013-09-04
To better understand the function of the myostatin gene and its promoter region in bovine, we amplified and sequenced the myostatin gene and promoter from the blood of Qinchuan and Red Angus cattle by using polymerase chain reaction. The sequences of Qinchuan and Red Angus cattle were compared with those of other cattle breeds available in GenBank. Exon splice sites were confirmed by mRNA sequencing. Compared to the published sequence (GenBank accession No. AF320998), 69 single nucleotide polymorphisms (SNPs) were identified in the Qinchuan myostatin gene, only one of which was an insertion mutation in Qinchuan cattle. There was a 16-bp insertion in the first 705-bp intron in 3 Qinchuan cattle. A total of 7 SNPs were identified in exon 3, in which the mutation occurred in the third base of the codon and was synonymous. On comparing the Qinchuan myostatin gene sequence to that of Red Angus cattle, a total of 50 SNPs were identified in the first and third exons. In addition, there were 18 SNPs identified in the Qinchuan cattle promoter region compared with those of other cattle compared to the Red Angus cattle myostatin promoter region. breeds (GenBank accession No. AF348479), but only 14 SNPs when compared to the Red Angus cattle myostatin promoter region.
Matsumoto, Junya; Nagaoka, Atsuko; Kunii, Yasuto; Miura, Itaru; Hino, Mizuki; Niwa, Shin-Ichi; Nawa, Hiroyuki; Takahashi, Hitoshi; Kakita, Akiyoshi; Yabe, Hirooki
2018-06-01
The relationships between -141C insertion/deletion (Ins/Del) polymorphisms in the dopamine D2 receptor gene and the two dopamine system integrators, i.e., dopamine- and cAMP-regulated phosphoprotein of molecular weight 32 kDa (DARPP-32) and calcineurin (CaN), are still unclear. In this study, we assessed the effect of this polymorphism on DARPP-32 and CaN protein expression in the postmortem striatum of patients with schizophrenia and control individuals. The expression levels of truncated DARPP and CaN were lower in Del allele carriers. These findings provide important insights into the mechanism by which this genotype could result in a poor response to antipsychotic drugs. Copyright © 2018 Elsevier B.V. All rights reserved.
Rizvi, Saliha; Raza, Syed T.; Siddiqi, Zeba; Abbas, Shania; Mahdi, Farzana
2015-01-01
Objectives: This study aimed to examine the association of angiotensin-converting enzyme (ACE) and glutathione S-transferase (GST) gene polymorphisms with body mass index (BMI) in hypertensive North Indians. Methods: This case-control study was carried out between May 2013 and November 2014 at the Era’s Lucknow Medical College & Hospital, Lucknow, India, and included 378 subjects divided into three groups. One group constituted 253 hypertensive individuals (sustained diastolic blood pressure of >90 mmHg and systolic blood pressure of >140 mmHg) who were subcategorised according to normal (<25 kg/m2) or high (≥25 kg/m2) BMI. The third group consisted of 125 age-, gender- and ethnically-matched normotensive controls with a normal BMI. Gene polymorphisms were evaluated by polymerase chain reaction. The genotypic and allelic frequency distribution among both groups were analysed. Results: A significant difference was found between GST theta 1-null and GST mu 1-positive genotype frequencies among the hypertensive overweight/obese individuals and controls (P = 0.014 and 0.033, respectively). However, no difference was observed in the frequency of ACE polymorphisms. ACE insertion/insertion genotype (P = 0.006), insertion and deletion alleles (P = 0.007 each) and GST theta 1-null and GST theta 1-positive genotypes (P = 0.006 each) were found to differ significantly between hypertensive cases and controls, regardless of BMI. Conclusion: ACE and GST gene polymorphisms were not associated with BMI but were significantly associated with hypertension among the studied group of North Indians. PMID:26629373
The evolution of small insertions and deletions in the coding genes of Drosophila melanogaster.
Chong, Zechen; Zhai, Weiwei; Li, Chunyan; Gao, Min; Gong, Qiang; Ruan, Jue; Li, Juan; Jiang, Lan; Lv, Xuemei; Hungate, Eric; Wu, Chung-I
2013-12-01
Studies of protein evolution have focused on amino acid substitutions with much less systematic analysis on insertion and deletions (indels) in protein coding genes. We hence surveyed 7,500 genes between Drosophila melanogaster and D. simulans, using D. yakuba as an outgroup for this purpose. The evolutionary rate of coding indels is indeed low, at only 3% of that of nonsynonymous substitutions. As coding indels follow a geometric distribution in size and tend to fall in low-complexity regions of proteins, it is unclear whether selection or mutation underlies this low rate. To resolve the issue, we collected genomic sequences from an isogenic African line of D. melanogaster (ZS30) at a high coverage of 70× and analyzed indel polymorphism between ZS30 and the reference genome. In comparing polymorphism and divergence, we found that the divergence to polymorphism ratio (i.e., fixation index) for smaller indels (size ≤ 10 bp) is very similar to that for synonymous changes, suggesting that most of the within-species polymorphism and between-species divergence for indels are selectively neutral. Interestingly, deletions of larger sizes (size ≥ 11 bp and ≤ 30 bp) have a much higher fixation index than synonymous mutations and 44.4% of fixed middle-sized deletions are estimated to be adaptive. To our surprise, this pattern is not found for insertions. Protein indel evolution appear to be in a dynamic flux of neutrally driven expansion (insertions) together with adaptive-driven contraction (deletions), and these observations provide important insights for understanding the fitness of new mutations as well as the evolutionary driving forces for genomic evolution in Drosophila species.
Brunelle, Brian W; Greenlee, Justin J; Seabury, Christopher M; Brown, Charles E; Nicholson, Eric M
2008-01-01
Background Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases that affect several mammalian species. At least three factors related to the host prion protein are known to modulate susceptibility or resistance to a TSE: amino acid sequence, atypical number of octapeptide repeats, and expression level. These factors have been extensively studied in breeds of Bos taurus cattle in relation to classical bovine spongiform encephalopathy (BSE). However, little is currently known about these factors in Bos indicus purebred or B. indicus × B. taurus composite cattle. The goal of our study was to establish the frequency of markers associated with enhanced susceptibility or resistance to classical BSE in B. indicus purebred and composite cattle. Results No novel or TSE-associated PRNP-encoded amino acid polymorphisms were observed for B. indicus purebred and composite cattle, and all had the typical number of octapeptide repeats. However, differences were observed in the frequencies of the 23-bp and 12-bp insertion/deletion (indel) polymorphisms associated with two bovine PRNP transcription regulatory sites. Compared to B. taurus, B. indicus purebred and composite cattle had a significantly lower frequency of 23-bp insertion alleles and homozygous genotypes. Conversely, B. indicus purebred cattle had a significantly higher frequency of 12-bp insertion alleles and homozygous genotypes in relation to both B. taurus and composite cattle. The origin of these disparities can be attributed to a significantly different haplotype structure within each species. Conclusion The frequencies of the 23-bp and 12-bp indels were significantly different between B. indicus and B. taurus cattle. No other known or potential risk factors were detected for the B. indicus purebred and composite cattle. To date, no consensus exists regarding which bovine PRNP indel region is more influential with respect to classical BSE. Should one particular indel region and associated genotypes prove more influential with respect to the incidence of classical BSE, differences regarding overall susceptibility and resistance for B. indicus and B. taurus cattle may be elucidated. PMID:18808703
Orangutan Alu quiescence reveals possible source element: support for ancient backseat drivers
2012-01-01
Background Sequence analysis of the orangutan genome revealed that recent proliferative activity of Alu elements has been uncharacteristically quiescent in the Pongo (orangutan) lineage, compared with all previously studied primate genomes. With relatively few young polymorphic insertions, the genomic landscape of the orangutan seemed like the ideal place to search for a driver, or source element, of Alu retrotransposition. Results Here we report the identification of a nearly pristine insertion possessing all the known putative hallmarks of a retrotranspositionally competent Alu element. It is located in an intronic sequence of the DGKB gene on chromosome 7 and is highly conserved in Hominidae (the great apes), but absent from Hylobatidae (gibbon and siamang). We provide evidence for the evolution of a lineage-specific subfamily of this shared Alu insertion in orangutans and possibly the lineage leading to humans. In the orangutan genome, this insertion contains three orangutan-specific diagnostic mutations which are characteristic of the youngest polymorphic Alu subfamily, AluYe5b5_Pongo. In the Homininae lineage (human, chimpanzee and gorilla), this insertion has acquired three different mutations which are also found in a single human-specific Alu insertion. Conclusions This seemingly stealth-like amplification, ongoing at a very low rate over millions of years of evolution, suggests that this shared insertion may represent an ancient backseat driver of Alu element expansion. PMID:22541534
Orangutan Alu quiescence reveals possible source element: support for ancient backseat drivers.
Walker, Jerilyn A; Konkel, Miriam K; Ullmer, Brygg; Monceaux, Christopher P; Ryder, Oliver A; Hubley, Robert; Smit, Arian Fa; Batzer, Mark A
2012-04-30
Sequence analysis of the orangutan genome revealed that recent proliferative activity of Alu elements has been uncharacteristically quiescent in the Pongo (orangutan) lineage, compared with all previously studied primate genomes. With relatively few young polymorphic insertions, the genomic landscape of the orangutan seemed like the ideal place to search for a driver, or source element, of Alu retrotransposition. Here we report the identification of a nearly pristine insertion possessing all the known putative hallmarks of a retrotranspositionally competent Alu element. It is located in an intronic sequence of the DGKB gene on chromosome 7 and is highly conserved in Hominidae (the great apes), but absent from Hylobatidae (gibbon and siamang). We provide evidence for the evolution of a lineage-specific subfamily of this shared Alu insertion in orangutans and possibly the lineage leading to humans. In the orangutan genome, this insertion contains three orangutan-specific diagnostic mutations which are characteristic of the youngest polymorphic Alu subfamily, AluYe5b5_Pongo. In the Homininae lineage (human, chimpanzee and gorilla), this insertion has acquired three different mutations which are also found in a single human-specific Alu insertion. This seemingly stealth-like amplification, ongoing at a very low rate over millions of years of evolution, suggests that this shared insertion may represent an ancient backseat driver of Alu element expansion.
Malueka, Rusdy Ghazali; Dwianingsih, Ery Kus; Sutarni, Sri; Bawono, Rheza Gandi; Bayuangga, Halwan Fuad; Gofir, Abdul; Setyopranoto, Ismail
2017-12-29
Insertion/deletion polymorphism in ACE gene (ACE I/D) is known to be associated with the occurrence of ischaemic stroke through its effect on pathogenesis of atherosclerosis and hypertension. This study was aimed to examine the association between this polymorphism with functional outcome of ischaemic stroke. This was a cross-sectional study. The subjects were patients with ischaemic stroke in a reference hospital in Yogyakarta, Indonesia. Data on demographic characteristics, stroke risk factors, comorbidities and stroke severity were assessed on admission. The functional outcome, Barthel index (BI), was assessed when the patients were discharged from the hospital. ACE I/D genotypes of the patients were identified by polymerase chain reaction (PCR). In total, 61 patients were included. Of these, 38 patients (62.3%) had II polymorphism, 22 patients (36.1%) had ID polymorphism and 1 patient (1.6%) had DD polymorphism in the ACE gene. There were significant differences in the functional outcomes between patients without D allele (II polymorphisms) and patients with D allele (ID and DD polymorphism) (mean BI on discharge: 75 ± 23.57 and 60.65 ± 27.15, respectively; p = 0.034). Multiple linear regression model showed that the availability of D allele is an independent variable negatively associated with functional outcome as assessed by BI (β = -0.232, p = 0.024). This study showed that the D allele in ACE I/D polymorphism is associated with worse functional outcomes. This highlights the possibility of further research to improve functional outcomes of ischaemic stroke by inhibiting the ACE system.
Jakubczak, J. L.; Zenni, M. K.; Woodruff, R. C.; Eickbush, T. H.
1992-01-01
R1 and R2 are distantly related non-long terminal repeat retrotransposable elements each of which inserts into a specific site in the 28S rRNA genes of most insects. We have analyzed aspects of R1 and R2 abundance and sequence variation in 27 geographical isolates of Drosophila melanogaster. The fraction of 28S rRNA genes containing these elements varied greatly between strains, 17-67% for R1 elements and 2-28% for R2 elements. The total percentage of the rDNA repeats inserted ranged from 32 to 77%. The fraction of the rDNA repeats that contained both of these elements suggested that R1 and R2 exhibit neither an inhibition of nor preference for insertion into a 28S gene already containing the other type of element. Based on the conservation of restriction sites in the elements of all strains, and sequence analysis of individual elements from three strains, nucleotide divergence is very low for R1 and R2 elements within or between strains (<0.6%). This sequence uniformity is the expected result of the forces of concerted evolution (unequal crossovers and gene conversion) which act on the rRNA genes themselves. Evidence for the role of retrotransposition in the turnover of R1 and R2 was obtained by using naturally occurring 5' length polymorphisms of the elements as markers for independent transposition events. The pattern of these different length 5' truncations of R1 and R2 was found to be diverse and unique to most strains analyzed. Because recombination can only, with time, amplify or eliminate those length variants already present, the diversity found in each strain suggests that retrotransposition has played a critical role in maintaining these elements in the rDNA repeats of D. melanogaster. PMID:1317313
Masking as an effective quality control method for next-generation sequencing data analysis.
Yun, Sajung; Yun, Sijung
2014-12-13
Next generation sequencing produces base calls with low quality scores that can affect the accuracy of identifying simple nucleotide variation calls, including single nucleotide polymorphisms and small insertions and deletions. Here we compare the effectiveness of two data preprocessing methods, masking and trimming, and the accuracy of simple nucleotide variation calls on whole-genome sequence data from Caenorhabditis elegans. Masking substitutes low quality base calls with 'N's (undetermined bases), whereas trimming removes low quality bases that results in a shorter read lengths. We demonstrate that masking is more effective than trimming in reducing the false-positive rate in single nucleotide polymorphism (SNP) calling. However, both of the preprocessing methods did not affect the false-negative rate in SNP calling with statistical significance compared to the data analysis without preprocessing. False-positive rate and false-negative rate for small insertions and deletions did not show differences between masking and trimming. We recommend masking over trimming as a more effective preprocessing method for next generation sequencing data analysis since masking reduces the false-positive rate in SNP calling without sacrificing the false-negative rate although trimming is more commonly used currently in the field. The perl script for masking is available at http://code.google.com/p/subn/. The sequencing data used in the study were deposited in the Sequence Read Archive (SRX450968 and SRX451773).
Kakuda, Tsuneo; Shojo, Hideki; Tanaka, Mayumi; Nambiar, Phrabhakaran; Minaguchi, Kiyoshi; Umetsu, Kazuo; Adachi, Noboru
2016-01-01
Mitochondrial DNA (mtDNA) serves as a powerful tool for exploring matrilineal phylogeographic ancestry, as well as for analyzing highly degraded samples, because of its polymorphic nature and high copy numbers per cell. The recent advent of complete mitochondrial genome sequencing has led to improved techniques for phylogenetic analyses based on mtDNA, and many multiplex genotyping methods have been developed for the hierarchical analysis of phylogenetically important mutations. However, few high-resolution multiplex genotyping systems for analyzing East-Asian mtDNA can be applied to extremely degraded samples. Here, we present a multiplex system for analyzing mitochondrial single nucleotide polymorphisms (mtSNPs), which relies on a novel amplified product-length polymorphisms (APLP) method that uses inosine-flapped primers and is specifically designed for the detailed haplogrouping of extremely degraded East-Asian mtDNAs. We used fourteen 6-plex polymerase chain reactions (PCRs) and subsequent electrophoresis to examine 81 haplogroup-defining SNPs and 3 insertion/deletion sites, and we were able to securely assign the studied mtDNAs to relevant haplogroups. Our system requires only 1×10−13 g (100 fg) of crude DNA to obtain a full profile. Owing to its small amplicon size (<110 bp), this new APLP system was successfully applied to extremely degraded samples for which direct sequencing of hypervariable segments using mini-primer sets was unsuccessful, and proved to be more robust than conventional APLP analysis. Thus, our new APLP system is effective for retrieving reliable data from extremely degraded East-Asian mtDNAs. PMID:27355212
Kakuda, Tsuneo; Shojo, Hideki; Tanaka, Mayumi; Nambiar, Phrabhakaran; Minaguchi, Kiyoshi; Umetsu, Kazuo; Adachi, Noboru
2016-01-01
Mitochondrial DNA (mtDNA) serves as a powerful tool for exploring matrilineal phylogeographic ancestry, as well as for analyzing highly degraded samples, because of its polymorphic nature and high copy numbers per cell. The recent advent of complete mitochondrial genome sequencing has led to improved techniques for phylogenetic analyses based on mtDNA, and many multiplex genotyping methods have been developed for the hierarchical analysis of phylogenetically important mutations. However, few high-resolution multiplex genotyping systems for analyzing East-Asian mtDNA can be applied to extremely degraded samples. Here, we present a multiplex system for analyzing mitochondrial single nucleotide polymorphisms (mtSNPs), which relies on a novel amplified product-length polymorphisms (APLP) method that uses inosine-flapped primers and is specifically designed for the detailed haplogrouping of extremely degraded East-Asian mtDNAs. We used fourteen 6-plex polymerase chain reactions (PCRs) and subsequent electrophoresis to examine 81 haplogroup-defining SNPs and 3 insertion/deletion sites, and we were able to securely assign the studied mtDNAs to relevant haplogroups. Our system requires only 1×10-13 g (100 fg) of crude DNA to obtain a full profile. Owing to its small amplicon size (<110 bp), this new APLP system was successfully applied to extremely degraded samples for which direct sequencing of hypervariable segments using mini-primer sets was unsuccessful, and proved to be more robust than conventional APLP analysis. Thus, our new APLP system is effective for retrieving reliable data from extremely degraded East-Asian mtDNAs.
Morimoto, Tomomi; Arii, Jun; Akashi, Hiroomi; Kawaguchi, Yasushi
2009-03-01
Information on sites in HSV genomes at which foreign gene(s) can be inserted without disrupting viral genes or affecting properties of the parental virus are important for basic research on HSV and development of HSV-based vectors for human therapy. The intergenic region between HSV-1 UL3 and UL4 genes has been reported to satisfy the requirements for such an insertion site. The UL3 and UL4 genes are oriented toward the intergenic region and, therefore, insertion of a foreign gene(s) into the region between the UL3 and UL4 polyadenylation signals should not disrupt any viral genes or transcriptional units. HSV-1 and HSV-2 each have more than 10 additional regions structurally similar to the intergenic region between UL3 and UL4. In the studies reported here, it has been demonstrated that insertion of a reporter gene expression cassette into several of the HSV-1 and HSV-2 intergenic regions has no effect on viral growth in cell culture or virulence in mice, suggesting that these multiple intergenic regions may be suitable HSV sites for insertion of foreign genes.
García Guerreiro, M P; Fontdevila, A
2007-01-01
A new transposable element, Isis, is identified as a LTR retrotransposon in Drosophila buzzatii. DNA sequence analysis shows that Isis contains three long ORFs similar to gag, pol and env genes of retroviruses. The ORF1 exhibits sequence homology to matrix, capsid and nucleocapsid gag proteins and ORF2 encodes a putative protease (PR), a reverse transcriptase (RT), an Rnase H (RH) and an integrase (IN) region. The analysis of a putative env product, encoded by the env ORF3, shows a degenerated protein containing several stop codons. The molecular study of the putative proteins coded by this new element shows striking similarities to both Ulysses and Osvaldo elements, two LTR retrotransposons, present in D. virilis and D. buzzatii, respectively. Comparisons of the predicted Isis RT to several known retrotransposons show strong phylogenetic relationships to gypsy-like elements, particulary to Ulysses retrotransposon. Studies of Isis chromosomal distribution show a strong hybridization signal in centromeric and pericentromeric regions, and a scattered distribution along all chromosomal arms. The existence of insertional polymorphisms between different strains and high molecular weight bands by Southern blot suggests the existence of full-sized copies that have been active recently. The presence of euchromatic insertion sites coincident between Isis and Osvaldo could indicate preferential insertion sites of Osvaldo element into Isis sequence or vice versa. Moreover, the presence of Isis in different species of the buzzatii complex indicates the ancient origin of this element.
Powrózek, Tomasz; Kowalski, Dariusz M; Krawczyk, Paweł; Ramlau, Rodryg; Kucharczyk, Tomasz; Kalinka-Warzocha, Ewa; Knetki-Wróblewska, Magdalena; Winiarczyk, Kinga; Dyszkiewicz, Wojciech; Krzakowski, Maciej; Milanowski, Janusz
2014-11-01
The combination of pemetrexed and platinum compound represents the standard regimen for first-line chemotherapy in malignant pleural mesothelioma patients. Pemetrexed is a multitarget antifolate agent that inhibits folate-dependent enzymes (eg, thymidylate synthase [TS]) and thus synthesis of nucleotides and DNA. Expression of TS and folate availability, regulated by gene polymorphisms, have implications for effectiveness of chemotherapy and the outcome of mesothelioma patients. The aim of this retrospective multicenter study was to assess the correlation between TS, 5,10-methylenetetrahydrofolate reductase (MTHFR) and excision repair cross-complementing group 1 (ERCC1) gene polymorphisms and the efficacy of pemetrexed-based first-line chemotherapy of mesothelioma patients. Fifty-nine mesothelioma patients (31 men with a median age of 62 years) treated in first-line chemotherapy with platinum in combination with pemetrexed or pemetrexed monotherapy were enrolled. Genomic DNA was isolated from peripheral blood. Using polymerase chain reaction and high resolution melt methods, the variable number of tandem repeat, the G>C single nucleotide polymorphism (SNP) in these repeats, and 6-base pair (bp) insertion/deletion polymorphism of the TS gene, the SNP of 677C>T in MTHFR, and 19007C>T in the ERCC1 gene were analyzed and correlated with disease control rate, progression-free survival (PFS), and overall survival (OS) of mesothelioma patients. Greater risk of early disease progression (PD), and shortening of PFS and OS were associated with several clinical factors (eg, anemia for early PD and OS), weight loss (for PFS and OS), and previous surgical treatment (for early PD, PFS, and OS). Insertion of 6-bp in both alleles of the TS gene (1494del6) was the only genetic factor that increased the incidence of early progression (P = .028) and shortening of median PFS (P = .06) in patients treated with pemetrexed-based chemotherapy. In multivariate analysis, the 1494del6 in the 3' untranslated region (UTR) of the TS gene also had a predictive role for PFS (P = .0185; hazard ratio, 2.3258 for +6/+6 homozygotes) in analyzed mesothelioma patients. Most analyzed polymorphisms in TS, MTHFR, and ERCC1 genes failed to predict outcome in mesothelioma patients treated with pemetrexed-based chemotherapy. However, different variants of 1494del6 in the 3' UTR of the TS gene were associated with differences in disease control rate and PFS of our patients. Copyright © 2014 Elsevier Inc. All rights reserved.
Assessing interethnic admixture using an X-linked insertion-deletion multiplex.
Ribeiro-Rodrigues, Elzemar Martins; dos Santos, Ney Pereira Carneiro; dos Santos, Andrea Kely Campos Ribeiro; Pereira, Rui; Amorim, António; Gusmão, Leonor; Zago, Marco Antonio; dos Santos, Sidney Emanuel Batista
2009-01-01
In this study, a PCR multiplex was optimized, allowing the simultaneous analysis of 13 X-chromosome Insertion/deletion polymorphisms (INDELs). Genetic variation observed in Africans, Europeans, and Native Americans reveals high inter-population variability. The estimated proportions of X-chromosomes in an admixed population from the Brazilian Amazon region show a predominant Amerindian contribution (approximately 41%), followed by European (approximately 32%) and African (approximately 27%) contributions. The proportion of Amerindian contribution based on X-linked data is similar to the expected value based on mtDNA and Y-chromosome information. The accuracy for assessing interethnic admixture, and the high differentiation between African, European, and Native American populations, demonstrates the suitability of this INDEL set to measure ancestry proportions in three-hybrid populations, as it is the case of Latin American populations.
Guenther, Daniel; Irarrázaval, Sebastian; Nishizawa, Yuichiro; Vernacchia, Cara; Thorhauer, Eric; Musahl, Volker; Irrgang, James J; Fu, Freddie H
2017-08-01
To propose a classification system for the shape of the tibial insertion site (TIS) of the anterior cruciate ligament (ACL) and to demonstrate the intra- and inter-rater agreement of this system. Due to variation in shape and size, different surgical approaches may be feasible to improve reconstruction of the TIS. One hundred patients with a mean age of 26 ± 11 years were included. The ACL was cut arthroscopically at the base of the tibial insertion site. Arthroscopic images were taken from the lateral and medial portal. Images were de-identified and duplicated. Two blinded observers classified the tibial insertion site according to a classification system. The tibial insertion site was classified as type I (elliptical) in 51 knees (51 %), type II (triangular) in 33 knees (33 %) and type III (C-shaped) in 16 knees (16 %). There was good agreement between raters when viewing the insertion site from the lateral portal (κ = 0.65) as well as from the medial portal (κ = 0.66). Intra-rater reliability was good to excellent. Agreement in the description of the insertion site between the medial and lateral portals was good for rater 1 and good for rater 2 (κ = 0.74 and 0.77, respectively). There is variation in the shape of the ACL TIS. The classification system is a repeatable and reliable tool to summarize the shape of the TIS using three common patterns. For clinical relevance, different shapes may require different types of reconstruction to ensure proper footprint restoration. Consideration of the individual TIS shape is required to prevent iatrogenic damage of adjacent structures like the menisci. III.
Buono, R J; Ferraro, T N; O'Connor, M J; Sperling, M R; Abbey, M; Finanger, E; Lohoff, F; Mulholland, N; Berrettini, W H
2000-02-07
Genetic linkage studies in rodents and humans have identified specific chromosomal regions harboring seizure susceptibility genes. We have identified a novel polymorphism in the human alpha 2 subunit gene (ATP1A2) of the sodium potassium transporting ATPase (NaK-pump), a candidate gene for human temporal lobe epilepsy (TLE) based on its chromosomal location and function in ion homeostasis. The polymorphism consists of a four base pair insertion 12 base pairs upstream of the start of exon 2. We performed an association study between this polymorphism and TLE. Our study did not find a significant difference in the frequency of this polymorphism between TLE patients and controls, indicating that this variation is not a major susceptibility factor. However, since the number of patients studied so far is small and the functional consequence of the polymorphism is unknown, the variation may yet be found to play a minor role in increased risk for seizure susceptibility. In contrast to the findings in TLE patients and controls, we did find a significant difference in the frequency of the variation between African Americans and persons of European descent. This finding demonstrates the potential effect of population stratification on studies of this type and supports the growing use of parental and familial samples for controls in association studies. Further study of this polymorphism is warranted as it may be involved in other disease processes for which there are known ethnic-specific susceptibilities. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:79-83, 2000. Copyright 2000 Wiley-Liss, Inc.
Gaspar, Paulo; Seixas, Susana; Rocha, Jorge
2004-04-01
The genetic variation at a compound nonrecombining haplotype system, consisting of the previously reported SB19.3 Alu insertion polymorphism and a newly identified adjacent short tandem repeat (STR), was studied in population samples from Portugal and São Tomé (Gulf of Guinea, West Africa). Age estimates based on the linked microsatellite variation suggest that the Alu insertion occurred about 190,000 years ago. In accordance with the global patterns of distribution of human genetic variation, the highest haplotype diversity was found in the African sample. This excess in African diversity was due to both a substantial reduction in heterozygosity at the Alu polymorphism and a lower STR variability associated with the predominant Alu insertion allele in the Portuguese sample. The high level of interpopulation differentiation observed at the Alu locus (F(ST) = 0.43) was interpreted under alternative selective and demographic scenarios. The need for compatibility between patterns of variation at the STR and Alu loci could be used to restrict the range of selection coefficients in selection-driven genetic hitchhiking frameworks and to favor demographic scenarios dominated by larger pre-expansion African population sizes. Taken together, the data show that the SB19.3 Alu-STR system is an informative marker that can be included in more extended batteries of compound haplotypes used in human evolutionary studies.
Mesarich, Carl H.; Rees-George, Jonathan; Gardner, Paul P.; Ghomi, Fatemeh Ashari; Gerth, Monica L.; Andersen, Mark T.; Rikkerink, Erik H. A.; Fineran, Peter C.
2017-01-01
Pseudomonas syringae pv. actinidiae (Psa), the causal agent of kiwifruit canker, is one of the most devastating plant diseases of recent times. We have generated two mini-Tn5-based random insertion libraries of Psa ICMP 18884. The first, a ‘phenotype of interest’ (POI) library, consists of 10,368 independent mutants gridded into 96-well plates. By replica plating onto selective media, the POI library was successfully screened for auxotrophic and motility mutants. Lipopolysaccharide (LPS) biosynthesis mutants with ‘Fuzzy-Spreader’-like morphologies were also identified through a visual screen. The second, a ‘mutant of interest’ (MOI) library, comprises around 96,000 independent mutants, also stored in 96-well plates, with approximately 200 individuals per well. The MOI library was sequenced on the Illumina MiSeq platform using Transposon-Directed Insertion site Sequencing (TraDIS) to map insertion sites onto the Psa genome. A grid-based PCR method was developed to recover individual mutants, and using this strategy, the MOI library was successfully screened for a putative LPS mutant not identified in the visual screen. The Psa chromosome and plasmid had 24,031 and 1,236 independent insertion events respectively, giving insertion frequencies of 3.65 and 16.6 per kb respectively. These data suggest that the MOI library is near saturation, with the theoretical probability of finding an insert in any one chromosomal gene estimated to be 97.5%. However, only 47% of chromosomal genes had insertions. This surprisingly low rate cannot be solely explained by the lack of insertions in essential genes, which would be expected to be around 5%. Strikingly, many accessory genes, including most of those encoding type III effectors, lacked insertions. In contrast, 94% of genes on the Psa plasmid had insertions, including for example, the type III effector HopAU1. These results suggest that some chromosomal sites are rendered inaccessible to transposon insertion, either by DNA-binding proteins or by the architecture of the nucleoid. PMID:28249011
Indel Group in Genomes (IGG) Molecular Genetic Markers1[OPEN
Burkart-Waco, Diana; Kuppu, Sundaram; Britt, Anne; Chetelat, Roger
2016-01-01
Genetic markers are essential when developing or working with genetically variable populations. Indel Group in Genomes (IGG) markers are primer pairs that amplify single-locus sequences that differ in size for two or more alleles. They are attractive for their ease of use for rapid genotyping and their codominant nature. Here, we describe a heuristic algorithm that uses a k-mer-based approach to search two or more genome sequences to locate polymorphic regions suitable for designing candidate IGG marker primers. As input to the IGG pipeline software, the user provides genome sequences and the desired amplicon sizes and size differences. Primer sequences flanking polymorphic insertions/deletions are produced as output. IGG marker files for three sets of genomes, Solanum lycopersicum/Solanum pennellii, Arabidopsis (Arabidopsis thaliana) Columbia-0/Landsberg erecta-0 accessions, and S. lycopersicum/S. pennellii/Solanum tuberosum (three-way polymorphic) are included. PMID:27436831
Pramanik, Sreemanta; Li, Honghua
2002-01-01
Direct polymerase chain reaction (PCR) detection of insertion/deletion (indel) polymorphisms requires sample homozygosity. For the indel polymorphisms that have the deletion allele with a relatively low frequency in the autosomal regions, direct PCR detection becomes difficult or impossible. The present study is, to our knowledge, the first designed to directly detect indel polymorphisms in a human autosomal region (i.e., the immunoglobulin VH region), through use of single haploid sperm cells as subjects. Unique marker sequences (n=32), spaced at ∼5-kb intervals, were selected near the 3′ end of the VH region. A two-round multiplex PCR protocol was used to amplify these sequences from single sperm samples from nine unrelated healthy donors. The parental haplotypes of the donors were determined by examining the presence or absence of these markers. Seven clustered markers in 6 of the 18 haplotypes were missing and likely represented a 35–40-kb indel polymorphism. The genotypes of the donors, with respect to this polymorphism, perfectly matched the expectation under Hardy-Weinberg equilibrium. Three VH gene segments, of which two are functional, are affected by this polymorphism. According to these results, >10% of individuals in the human population may not have these gene segments in their genome, and ∼44% may have only one copy of these gene segments. The biological impact of this polymorphism would be very interesting to study. The approach used in the present study could be applied to understand the physical structure and diversity of all other autosomal regions. PMID:12442231
Hwang, Hanshin; Taylor, John-Stephen
2005-03-29
We have recently reported that pyrene nucleotide is preferentially inserted opposite an abasic site, the 3'-T of a thymine dimer, and most undamaged bases by yeast DNA polymerase eta (pol eta). Because pyrene is a nonpolar molecule with no H-bonding ability, the unusually high efficiencies of dPMP insertion are ascribed to its superior base stacking ability, and underscore the importance of base stacking in the selection of nucleotides by pol eta. To investigate the role of H-bonding and base pair geometry in the selection of nucleotides by pol eta, we determined the insertion efficiencies of the base-modified nucleotides 2,6-diaminopurine, 2-aminopurine, 6-chloropurine, and inosine which would make a different number of H-bonds with the template base depending on base pair geometry. Watson-Crick base pairing appears to play an important role in the selection of nucleotide analogues for insertion opposite C and T as evidenced by the decrease in the relative insertion efficiencies with a decrease in the number of Watson-Crick H-bonds and an increase in the number of donor-donor and acceptor-acceptor interactions. The selectivity of nucleotide insertion is greater opposite the 5'-T than the 3'-T of the thymine dimer, in accord with previous work suggesting that the 5'-T is held more rigidly than the 3'-T. Furthermore, insertion of A opposite both Ts of the dimer appears to be mediated by Watson-Crick base pairing and not by Hoogsteen base pairing based on the almost identical insertion efficiencies of A and 7-deaza-A, the latter of which lacks H-bonding capability at N7. The relative efficiencies for insertion of nucleotides that can form Watson-Crick base pairs parallel those for the Klenow fragment, whereas the Klenow fragment more strongly discriminates against mismatches, in accord with its greater shape selectivity. These results underscore the importance of H-bonding and Watson-Crick base pair geometry in the selection of nucleotides by both pol eta and the Klenow fragment, and the lesser role of shape selection in insertion by pol eta due to its more open and less constrained active site.
Role of ACE and PAI-1 Polymorphisms in the Development and Progression of Diabetic Retinopathy
Saleem, Saba; Azam, Aisha; Maqsood, Sundus Ijaz; Muslim, Irfan; Bashir, Shaheena; Fazal, Nosheen; Riaz, Moeen; Ali, Syeda Hafiza Benish; Niazi, Muhammad Khizar; Ishaq, Mazhar; Waheed, Nadia Khalida; Qamar, Raheel; Azam, Maleeha
2015-01-01
In the present study we determined the association of angiotensin converting enzyme (ACE) and plasminogen activator inhibitor-1 (PAI-1) gene polymorphisms with diabetic retinopathy (DR) and its sub-clinical classes in Pakistani type 2 diabetic patients. A total of 353 diabetic subjects including 160 DR and 193 diabetic non retinopathy (DNR) as well as 198 healthy controls were genotyped by allele specific polymerase chain reaction (PCR) for ACE Insertion/Deletion (ID) polymorphism, rs4646994 in intron 16 and PAI-1 4G/5G (deletion/insertion) polymorphism, rs1799768 in promoter region of the gene. To statistically assess the genotype-phenotype association, multivariate logistic regression analysis was applied to the genotype data of DR, DNR and control individuals as well as the subtypes of DR. The ACE genotype ID was found to be significantly associated with DR (p = 0.009, odds ratio (OR) 1.870 [95% confidence interval (CI) = 1.04–3.36]) and its sub-clinical class non-proliferative DR (NPDR) (p = 0.006, OR 2.250 [95% CI = 1.098–4.620]), while PAI polymorphism did not show any association with DR in the current cohort. In conclusion in Pakistani population the ACE ID polymorphism was observed to be significantly associated with DR and NPDR, but not with the severe form of the disease i.e. proliferative DR (PDR). PMID:26658948
Tan, Peng Chiong; Mackeen, Anjana; Khong, Su Yen; Omar, Siti Zawiah; Azmi, M. A. Noor
2016-01-01
A peripheral intravenous catheter is often inserted as part of care during labour. The catheter is inserted into the back of the hand or lower forearm vein in usual practice. There is no trial data to guide the care provider on which is the better insertion site in any clinical setting. 307 women admitted to the labour ward who required insertion of intravenous catheter were randomised to back of hand or lower forearm vein catheter insertion. Catheter insertion is by junior to mid-grade providers. We evaluated insertion success at the first attempt, pain during insertion and catheter replacement due to malfunction as main outcomes. After catheter removal, we recorded patient satisfaction with site, future site preference and insertion site swelling, bruising, tenderness, vein thrombosis and pain. Insertion of a catheter into back of hand vein is more likely to be successful at the first attempt. Insertion pain score, catheter replacement rate, patient satisfaction, patient fidelity to site in a future insertion and insertion site complications rate are not different between trial arms. In conclusion, both insertion sites are suitable; the back of the hand vein maybe easier to cannulate and seems to be preferred by our frontline providers. PMID:26987593
Molecular spectrum of somaclonal variation in regenerated rice revealed by whole-genome sequencing.
Miyao, Akio; Nakagome, Mariko; Ohnuma, Takako; Yamagata, Harumi; Kanamori, Hiroyuki; Katayose, Yuichi; Takahashi, Akira; Matsumoto, Takashi; Hirochika, Hirohiko
2012-01-01
Somaclonal variation is a phenomenon that results in the phenotypic variation of plants regenerated from cell culture. One of the causes of somaclonal variation in rice is the transposition of retrotransposons. However, many aspects of the mechanisms that result in somaclonal variation remain undefined. To detect genome-wide changes in regenerated rice, we analyzed the whole-genome sequences of three plants independently regenerated from cultured cells originating from a single seed stock. Many single-nucleotide polymorphisms (SNPs) and insertions and deletions (indels) were detected in the genomes of the regenerated plants. The transposition of only Tos17 among 43 transposons examined was detected in the regenerated plants. Therefore, the SNPs and indels contribute to the somaclonal variation in regenerated rice in addition to the transposition of Tos17. The observed molecular spectrum was similar to that of the spontaneous mutations in Arabidopsis thaliana. However, the base change ratio was estimated to be 1.74 × 10(-6) base substitutions per site per regeneration, which is 248-fold greater than the spontaneous mutation rate of A. thaliana.
Angiotensin-converting enzyme genetic polymorphism: its impact on cardiac remodeling
de Albuquerque, Felipe Neves; Brandão, Andréa Araujo; da Silva, Dayse Aparecida; Mourilhe-Rocha, Ricardo; Duque, Gustavo Salgado; Gondar, Alyne Freitas Pereira; Neves, Luiza Maceira de Almeida; Bittencourt, Marcelo Imbroinise; Pozzan, Roberto; de Albuquerque, Denilson Campos
2014-01-01
Background The role of angiotensin-converting enzyme genetic polymorphisms as a predictor of echocardiographic outcomes on heart failure is yet to be established. The local profile should be identified so that the impact of those genotypes on the Brazilian population could be identified. This is the first study on exclusively non-ischemic heart failure over a follow-up longer than 5 years. Objective To determine the distribution of angiotensin-converting enzyme genetic polymorphism variants and their relation with echocardiographic outcome of patients with non-ischemic heart failure. Methods Secondary analysis of the medical records of 111 patients and identification of the angiotensin-converting enzyme genetic polymorphism variants, classified as DD (Deletion/Deletion), DI (Deletion/Insertion) or II (Insertion/Insertion). Results The cohort means were as follows: follow-up, 64.9 months; age, 59.5 years; male sex, 60.4%; white skin color, 51.4%; use of beta-blockers, 98.2%; and use of angiotensin-converting-enzyme inhibitors or angiotensin receptor blocker, 89.2%. The angiotensin-converting enzyme genetic polymorphism distribution was as follows: DD, 51.4%; DI, 44.1%; and II, 4.5%. No difference regarding the clinical characteristics or treatment was observed between the groups. The final left ventricular systolic diameter was the only isolated echocardiographic variable that significantly differed between the angiotensin-converting enzyme genetic polymorphisms: 59.2 ± 1.8 for DD versus 52.3 ± 1.9 for DI versus 59.2 ± 5.2 for II (p = 0.029). Considering the evolutionary behavior, all echocardiographic variables (difference between the left ventricular ejection fraction at the last and first consultation; difference between the left ventricular systolic diameter at the last and first consultation; and difference between the left ventricular diastolic diameter at the last and first consultation) differed between the genotypes (p = 0.024; p = 0.002; and p = 0.021, respectively). Conclusion The distribution of the angiotensin-converting enzyme genetic polymorphisms differed from that of other studies with a very small number of II. The DD genotype was independently associated with worse echocardiographic outcome, while the DI genotype, with the best echocardiographic profile (increased left ventricular ejection fraction and decreased left ventricular diameters). PMID:24270863
Angiotensin-converting enzyme genetic polymorphism: its impact on cardiac remodeling.
Albuquerque, Felipe Neves de; Brandão, Andréa Araujo; Silva, Dayse Aparecida da; Mourilhe-Rocha, Ricardo; Duque, Gustavo Salgado; Gondar, Alyne Freitas Pereira; Neves, Luiza Maceira de Almeida; Bittencourt, Marcelo Imbroinise; Pozzan, Roberto; Albuquerque, Denilson Campos de
2014-01-01
The role of angiotensin-converting enzyme genetic polymorphisms as a predictor of echocardiographic outcomes on heart failure is yet to be established. The local profile should be identified so that the impact of those genotypes on the Brazilian population could be identified. This is the first study on exclusively non-ischemic heart failure over a follow-up longer than 5 years. To determine the distribution of angiotensin-converting enzyme genetic polymorphism variants and their relation with echocardiographic outcome of patients with non-ischemic heart failure. Secondary analysis of the medical records of 111 patients and identification of the angiotensin-converting enzyme genetic polymorphism variants, classified as DD (Deletion/Deletion), DI (Deletion/Insertion) or II (Insertion/Insertion). The cohort means were as follows: follow-up, 64.9 months; age, 59.5 years; male sex, 60.4%; white skin color, 51.4%; use of beta-blockers, 98.2%; and use of angiotensin-converting-enzyme inhibitors or angiotensin receptor blocker, 89.2%. The angiotensin-converting enzyme genetic polymorphism distribution was as follows: DD, 51.4%; DI, 44.1%; and II, 4.5%. No difference regarding the clinical characteristics or treatment was observed between the groups. The final left ventricular systolic diameter was the only isolated echocardiographic variable that significantly differed between the angiotensin-converting enzyme genetic polymorphisms: 59.2 ± 1.8 for DD versus 52.3 ± 1.9 for DI versus 59.2 ± 5.2 for II (p = 0.029). Considering the evolutionary behavior, all echocardiographic variables (difference between the left ventricular ejection fraction at the last and first consultation; difference between the left ventricular systolic diameter at the last and first consultation; and difference between the left ventricular diastolic diameter at the last and first consultation) differed between the genotypes (p = 0.024; p = 0.002; and p = 0.021, respectively). The distribution of the angiotensin-converting enzyme genetic polymorphisms differed from that of other studies with a very small number of II. The DD genotype was independently associated with worse echocardiographic outcome, while the DI genotype, with the best echocardiographic profile (increased left ventricular ejection fraction and decreased left ventricular diameters).
An innovative SNP genotyping method adapting to multiple platforms and throughputs.
Long, Y M; Chao, W S; Ma, G J; Xu, S S; Qi, L L
2017-03-01
An innovative genotyping method designated as semi-thermal asymmetric reverse PCR (STARP) was developed for genotyping individual SNPs with improved accuracy, flexible throughputs, low operational costs, and high platform compatibility. Multiplex chip-based technology for genome-scale genotyping of single nucleotide polymorphisms (SNPs) has made great progress in the past two decades. However, PCR-based genotyping of individual SNPs still remains problematic in accuracy, throughput, simplicity, and/or operational costs as well as the compatibility with multiple platforms. Here, we report a novel SNP genotyping method designated semi-thermal asymmetric reverse PCR (STARP). In this method, genotyping assay was performed under unique PCR conditions using two universal priming element-adjustable primers (PEA-primers) and one group of three locus-specific primers: two asymmetrically modified allele-specific primers (AMAS-primers) and their common reverse primer. The two AMAS-primers each were substituted one base in different positions at their 3' regions to significantly increase the amplification specificity of the two alleles and tailed at 5' ends to provide priming sites for PEA-primers. The two PEA-primers were developed for common use in all genotyping assays to stringently target the PCR fragments generated by the two AMAS-primers with similar PCR efficiencies and for flexible detection using either gel-free fluorescence signals or gel-based size separation. The state-of-the-art primer design and unique PCR conditions endowed STARP with all the major advantages of high accuracy, flexible throughputs, simple assay design, low operational costs, and platform compatibility. In addition to SNPs, STARP can also be employed in genotyping of indels (insertion-deletion polymorphisms). As vast variations in DNA sequences are being unearthed by many genome sequencing projects and genotyping by sequencing, STARP will have wide applications across all biological organisms in agriculture, medicine, and forensics.
McAllister, Lauren J; Bent, Stephen J; Petty, Nicola K; Skippington, Elizabeth; Beatson, Scott A; Paton, James C; Paton, Adrienne W
2016-01-04
Enterohemorrhagic Escherichia coli (EHEC) is an important cause of diarrhea and hemolytic-uremic syndrome (HUS) worldwide. Australia's worst outbreak of HUS occurred in Adelaide in 1995 and was one of the first major HUS outbreaks attributed to a non-O157 Shiga-toxigenic E. coli (STEC) strain. Molecular analyses conducted at the time suggested that the outbreak was caused by an O111:H(-) clone, with strains from later in the outbreak harboring an extra copy of the genes encoding the potent Shiga toxin 2 (Stx2). Two decades later, we have used next-generation sequencing to compare two isolates from early and late in this important outbreak. We analyzed genetic content, single-nucleotide polymorphisms (SNPs), and prophage insertion sites; for the latter, we demonstrate how paired-end sequence data can be leveraged to identify such insertion sites. The two strains are genetically identical except for six SNP differences and the presence of not one but two additional Stx2-converting prophages in the later isolate. Isolates from later in the outbreak were associated with higher levels of morbidity, suggesting that the presence of the additional Stx2-converting prophages is significant in terms of the virulence of this clone. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Khitrinskaia, I Iu; Khar'kov, V N; Voevoda, M I; Stepanova, V A
2014-01-01
We for the first time have examined the autosomal gene pool of the Siberia, Central Asian and the Far East populations (27 populations of 12 ethnic groups) using a set of polymorphic Alu insertions in the human genome. The results of the analysis testify (i) to a significant level of genetic diversity in the Northern Eurasian populations and (ii) to a considerable differentiation of gene pool in the population of this region. It has been shown that at the CD4 locus, the frequency of Alu (-) is inversely related to the Mongoloid component of the population, the lowest and highest frequencies of the Alu deletion at locus CD4 were recorded respectively in Eskimo (0.012) and Russian and Ukrainian (0.35). The analysis of gene flow proved Caucasoid populations (Russian, Tajik and Uzbek), as well as those of Turkic ethnic groups from the Southern Siberia (Altaians and Tuvinians) and Khanty and Mansy populations to be the recipients of a considerable gene flow from the outside of the concerned population system, as compared with the East Siberian and the Far East ethnic groups. The results of the correlation analysis received with use polymorphic Alu insertion testify to the greatest correlation of genetic distances with anthropological characteristics of populations.
Wendt, Frank R; Warshauer, David H; Zeng, Xiangpei; Churchill, Jennifer D; Novroski, Nicole M M; Song, Bing; King, Jonathan L; LaRue, Bobby L; Budowle, Bruce
2016-11-01
Short tandem repeat (STR) loci are the traditional markers used for kinship, missing persons, and direct comparison human identity testing. These markers hold considerable value due to their highly polymorphic nature, amplicon size, and ability to be multiplexed. However, many STRs are still too large for use in analysis of highly degraded DNA. Small bi-allelic polymorphisms, such as insertions/deletions (INDELs), may be better suited for analyzing compromised samples, and their allele size differences are amenable to analysis by capillary electrophoresis. The INDEL marker allelic states range in size from 2 to 6 base pairs, enabling small amplicon size. In addition, heterozygote balance may be increased by minimizing preferential amplification of the smaller allele, as is more common with STR markers. Multiplexing a large number of INDELs allows for generating panels with high discrimination power. The Nextera™ Rapid Capture Custom Enrichment Kit (Illumina, Inc., San Diego, CA) and massively parallel sequencing (MPS) on the Illumina MiSeq were used to sequence 68 well-characterized INDELs in four major US population groups. In addition, the STR Allele Identification Tool: Razor (STRait Razor) was used in a novel way to analyze INDEL sequences and detect adjacent single nucleotide polymorphisms (SNPs) and other polymorphisms. This application enabled the discovery of unique allelic variants, which increased the discrimination power and decreased the single-locus random match probabilities (RMPs) of 22 of these well-characterized INDELs which can be considered as microhaplotypes. These findings suggest that additional microhaplotypes containing human identification (HID) INDELs may exist elsewhere in the genome. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Le Hello, Claire; Fradin, Sabine; Morello, Rémy; Coffin, Olivier; Maïza, Dominique; Hamon, Martial
2011-04-01
Angiotensin-converting enzyme insertion/deletion (rs4340) and angiotensin II type 1 receptor A1166C (rs5186) gene polymorphisms may be involved in coronary heart disease (CHD). This study was designed to evaluate potential relationships between these polymorphisms and the risk of long-term all-cause mortality and major adverse cardiovascular events (MACE) in patients requiring revascularization for atherothrombotic disease (ATD) lesions. This prospective observational study concerned patients referred for supra-aortic vessel disease (SVD), CHD, peripheral artery occlusive disease (PAOD) or visceral artery disease (VAD). Collected data included ATD referral site, ATD symptoms, personal and familial medical histories, ATD extent, vascular risk factors, biological values, medication use and rs4340 and rs5186 polymorphisms. The primary end point was all-cause mortality. The secondary end point, MACE, included cardiovascular death, clinical ischemic event related to SVD, CHD, PAOD or VAD. The cohort comprised 956 patients of whom 872 (91.2%) were genotyped and followed for 21.1 ± 9.9 months. Patients were referred for SVD (25.9%), CHD (42.3%), PAOD (35.2%) or VAD (1.6%). All-cause mortality and MACE rates were 7.6 and 27.2%, respectively. When comparing I/D + D/D vs. I/I genotypes, rs4340 polymorphism was associated with higher all-cause mortality rates according to uni- and multivariate analyses (p=0.008 and 0.011, respectively). Other differences were not significant (rs4340 polymorphism and MACE, rs5186 polymorphism and all-cause mortality and MACE). No interaction was found between the polymorphisms. Other independent predictors of all-cause mortality included PAOD history, SVD history, body mass index <25 kg/m(2), HbA(1c) ≥6.5%, absence of dyslipidemia and no use of aspirin. rs4340 polymorphism is associated with long-term all-cause mortality in advanced ATD patients requiring revascularization, whereas rs5186 polymorphism does not. Copyright © 2011 IMSS. Published by Elsevier Inc. All rights reserved.
Jung, Yong Wook; Jeon, Young Joo; Park, Hye Mi; Lee, Bo Eun; Rah, Hyungchul; Lee, Woo Sik; Yoon, Tae Ki; Kim, Nam Keun
2013-05-01
The purpose of this study was to evaluate the relationship between angiotensin-converting enzyme (ACE; insertion/deletion), angiotensinogen (AGT M235T), and angiotensin II type 1 receptor (AT1R 1166A>C) and the prevalence of primary ovarian insufficiency (POI) in Korean women. A total of 133 women with POI and 238 controls were genotyped for polymorphic sites in each gene using polymerase chain reaction-restriction fragment length polymorphism analysis. ACE ID and ID + II variants occurred more frequently in women with POI than in controls (odds ratio [OR], 1.830; 95% CI, 1.040-3.221; P = 0.040; and OR, 1.797; 95% CI, 1.055-3.060; P = 0.031, respectively). The AT1R 1166AC genotype occurred more frequently in participants with POI than in controls (OR, 3.171; 95% CI, 1.562-6.436; P = 0.002). Comparing the combined genotype frequencies of ACE/AT1R revealed that the frequencies of ID/AA, ID/AC, and II/AC were higher in participants than in controls (OR, 1.916; 95% CI, 1.053-3.485; P = 0.043; OR, 3.544; 95% CI, 1.207-10.407; P = 0.036; and OR, 7.875; 95% CI, 2.224-27.881; P = 0.001, respectively). The TT/AC genotype for combined genotyping of AGT/AT1R was more frequently observed in the POI group than in the control group (OR, 3.472; 95% CI, 1.450-8.313; P = 0.006). In multifactor dimensionality reduction-based haplotype analysis, the I-T-C genotype of ACE/AGT/AT1R was a possible predisposing factor for POI (OR, 4.678; 95% CI, 1.721-12.717; P = 0.002). This study demonstrates that polymorphisms in the renin-angiotensin system are related to the prevalence of POI. Thus, these renin-angiotensin system genes may serve as a novel marker for predicting the development of POI.
Wang, Sihua; Ding, Mingcui; Duan, Xiaoran; Wang, Tuanwei; Feng, Xiaolei; Wang, Pengpeng; Yao, Wu; Wu, Yongjun; Yan, Zhen; Feng, Feifei; Yu, Songcheng; Wang, Wei
2017-09-01
It has been shown that the single nucleotide polymorphism (SNP) of the rs2735940 site in the human telomerase reverse transcriptase ( hTERT ) gene is associated with increased cancer risk. The traditional method to detect SNP genotypes is polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). However, there is a limitation to utilizing PCR-RFLP due to a lack of proper restriction enzyme sites at many polymorphic loci. This study used an improved PCR-RFLP method with a mismatched base for detection of the SNP rs2735940. A new restriction enzyme cutting site was created by created restriction site PCR (CRS-PCR), and in addition, the restriction enzyme Msp I for CRS-PCR was cheaper than other enzymes. We used this novel assay to determine the allele frequencies in 552 healthy Chinese Han individuals, and found the allele frequencies to be 63% for allele C and 37% for allele T In summary, the modified PCR-RFLP can be used to detect the SNP of rs2735940 with low cost and high efficiency. © 2017 by the Association of Clinical Scientists, Inc.
[Analysis of ethnogeographic groups of Kazakhs based on nuclear genome DNA polymorphism].
Salimova, A Z; Kutuev, I A; Khusainova, R I; Akhmetova, V L; Sviatova, G S; Berezina, G M; Khusnutdinova, E K
2005-07-01
Eight nuclear DNA loci, including six Alu insertions (ACE, APOA1, PV92, TPA25, Ya5NBC27, and Ya5NBC148), 32-bp deletion in the CCR5 gene, and VNTR locus at the eNOS gene, were examined in three ethnogeographic groups of Kazakhs (342 individuals). The individuals examined lived in southeastern, central, and southwestern regions of Kazakhstan, and according to their tribal attribution, belonged to the Senior, Middle, and Junior Zhuzes. The Alu insertions appeared to be polymorphic in all populations examined: the insertion frequency varied from 0.264 in the populations of the Senior and Middle Zhuzes at the Ya5NBC27 and Ya5NBC148 loci, to 0.827 in Kazakhs of the Middle Zhuz at the APOA1 locus. In Kazakh groups examined only two alleles of the eNOS VNTR locus were detected with the number of repeats constituting four (A) and five (B) copies. The highest frequency of A allele was found in Kazakhs from the Junior Zhuz (0.113), while the highest frequency of B allele was detected in population of the Senior Zhuz (0.893). The frequency of the 32-bp deletion in the chemokine receptor CCR5 gene varied from 0.027 in the Junior Zhuz to 0.045 in the Senior Zhuz. Kazakhs showed high genetic diversity (Hex = 0.376). In general, in three ethnogeographic groups of Kazakhs, the coefficient of gene differentiation (G(ST)) over eight diallelic markers of nuclear genome constituted 1.1%. The differences in the Alu insertions made the highest contribution to the among-population diversity (G(ST) = 1.2%).
The relationship between ACE polymorphism and panic disorder.
Gulec-Yılmaz, Seda; Gulec, Huseyın; Dalan, Altay Burak; Cetın, Bugra; Tımırcı-Kahraman, Ozlem; Ogut, Dıcle Bılge; Atasoy, Hande; Dırımen, Gulız Arikan; Gultekın, Guldal Inal; Isbır, Turgay
2014-01-01
The angiotensin converting enzyme (ACE) gene, which has been found to have an insertion and deletion polymorphism (I/D), is of increasing interest in etiology and treatment of various psychiatric disorders such as panic disorder. The present study aimed to investigate the relationship between ACE polymorphism and panic disorder. In this study, 43 patients diagnosed with panic disorder at the Erenköy Mental and Neurological Diseases Training and Research Hospital, Istanbul and 41 healthy controls were enrolled. The ACE gene insertion/deletion polymorphism of exon 16 was evaluated using the polymerase chain reaction method. There was a significant association between I/D genotype and panic disorder (p=0.003). However, the frequency of the I allele was found to be significantly higher in patients compared to controls (p=0.002). In addition, we recognized a significant association between I/D polymorphism and respiratory-type panic disorder in patients. Carriers of the D allele also had an increased risk of respiratory type panic disorder patients (p=0.034). Moreover, the result of Spearman correlation analysis showed an association with ACE D allele and severity of panic disorder (p<0.001). We suggest that the I/D polymorphism of the ACE gene is associated with panic disorder and particularly respiratory-type panic disorder in patients. The I/D polymorphism of the ACE gene seems to influence therapeutic outcome in patients suffering from panic disorder. Our results indicate that ACE D allele is associated with the severity of panic disorder. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
Diekmann, Kerstin; Hodkinson, Trevor R; Wolfe, Kenneth H; van den Bekerom, Rob; Dix, Philip J; Barth, Susanne
2009-06-01
Lolium perenne L. (perennial ryegrass) is globally one of the most important forage and grassland crops. We sequenced the chloroplast (cp) genome of Lolium perenne cultivar Cashel. The L. perenne cp genome is 135 282 bp with a typical quadripartite structure. It contains genes for 76 unique proteins, 30 tRNAs and four rRNAs. As in other grasses, the genes accD, ycf1 and ycf2 are absent. The genome is of average size within its subfamily Pooideae and of medium size within the Poaceae. Genome size differences are mainly due to length variations in non-coding regions. However, considerable length differences of 1-27 codons in comparison of L. perenne to other Poaceae and 1-68 codons among all Poaceae were also detected. Within the cp genome of this outcrossing cultivar, 10 insertion/deletion polymorphisms and 40 single nucleotide polymorphisms were detected. Two of the polymorphisms involve tiny inversions within hairpin structures. By comparing the genome sequence with RT-PCR products of transcripts for 33 genes, 31 mRNA editing sites were identified, five of them unique to Lolium. The cp genome sequence of L. perenne is available under Accession number AM777385 at the European Molecular Biology Laboratory, National Center for Biotechnology Information and DNA DataBank of Japan.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Patra, Amritaj; Zhang, Qianqian; Lei, Li
2015-02-09
The most prevalent lesion in DNA is an abasic site resulting from glycolytic cleavage of a base. In a number of cellular studies, abasic sites preferentially code for dATP insertion (the “A rule”). In some cases frameshifts are also common. X-ray structures with abasic sites in oligonucleotides have been reported for several microbial and human DNA polymerases (pols), e.g. Dpo4, RB69, KlenTaq, yeast pol ι, human (h) pol ι, and human pol β. We reported previously that hpol η is a major pol involved in abasic site bypass (Choi, J.-Y., Lim, S., Kim, E. J., Jo, A., and Guengerich, F.more » P. (2010 J. Mol. Biol. 404, 34–44). hpol η inserted all four dNTPs in steady-state and pre-steady-state assays, preferentially inserting A and G. In LC-MS analysis of primer-template pairs, A and G were inserted but little C or T was inserted. Frameshifts were observed when an appropriate pyrimidine was positioned 5' to the abasic site in the template. In x-ray structures of hpol η with a non-hydrolyzable analog of dATP or dGTP opposite an abasic site, H-bonding was observed between the phosphate 5' to the abasic site and water H-bonded to N1 and N6 of A and N1 and O6 of G nucleoside triphosphate analogs, offering an explanation for what appears to be a “purine rule.” A structure was also obtained for an A inserted and bonded in the primer opposite the abasic site, but it did not pair with a 5' T in the template. Finally, we conclude that hpol η, a major copying enzyme with abasic sites, follows a purine rule, which can also lead to frameshifts. The phenomenon can be explained with H-bonds.« less
Brenner, Everton A; Zein, Imad; Chen, Yongsheng; Andersen, Jeppe R; Wenzel, Gerhard; Ouzunova, Milena; Eder, Joachim; Darnhofer, Birte; Frei, Uschi; Barrière, Yves; Lübberstedt, Thomas
2010-02-12
OMT (O-methyltransferase) genes are involved in lignin biosynthesis, which relates to stover cell wall digestibility. Reduced lignin content is an important determinant of both forage quality and ethanol conversion efficiency of maize stover. Variation in genomic sequences coding for COMT, CCoAOMT1, and CCoAOMT2 was analyzed in relation to stover cell wall digestibility for a panel of 40 European forage maize inbred lines, and re-analyzed for a panel of 34 lines from a published French study. Different methodologies for association analysis were performed and compared. Across association methodologies, a total number of 25, 12, 1, 6 COMT polymorphic sites were significantly associated with DNDF, OMD, NDF, and WSC, respectively. Association analysis for CCoAOMT1 and CCoAOMT2 identified substantially fewer polymorphic sites (3 and 2, respectively) associated with the investigated traits. Our re-analysis on the 34 lines from a published French dataset identified 14 polymorphic sites significantly associated with cell wall digestibility, two of them were consistent with our study. Promising polymorphisms putatively causally associated with variability of cell wall digestibility were inferred from the total number of significantly associated SNPs/Indels. Several polymorphic sites for three O-methyltransferase loci were associated with stover cell wall digestibility. All three tested genes seem to be involved in controlling DNDF, in particular COMT. Thus, considerable variation among Bm3 wildtype alleles can be exploited for improving cell-wall digestibility. Target sites for functional markers were identified enabling development of efficient marker-based selection strategies.
2010-01-01
Background OMT (O-methyltransferase) genes are involved in lignin biosynthesis, which relates to stover cell wall digestibility. Reduced lignin content is an important determinant of both forage quality and ethanol conversion efficiency of maize stover. Results Variation in genomic sequences coding for COMT, CCoAOMT1, and CCoAOMT2 was analyzed in relation to stover cell wall digestibility for a panel of 40 European forage maize inbred lines, and re-analyzed for a panel of 34 lines from a published French study. Different methodologies for association analysis were performed and compared. Across association methodologies, a total number of 25, 12, 1, 6 COMT polymorphic sites were significantly associated with DNDF, OMD, NDF, and WSC, respectively. Association analysis for CCoAOMT1 and CCoAOMT2 identified substantially fewer polymorphic sites (3 and 2, respectively) associated with the investigated traits. Our re-analysis on the 34 lines from a published French dataset identified 14 polymorphic sites significantly associated with cell wall digestibility, two of them were consistent with our study. Promising polymorphisms putatively causally associated with variability of cell wall digestibility were inferred from the total number of significantly associated SNPs/Indels. Conclusions Several polymorphic sites for three O-methyltransferase loci were associated with stover cell wall digestibility. All three tested genes seem to be involved in controlling DNDF, in particular COMT. Thus, considerable variation among Bm3 wildtype alleles can be exploited for improving cell-wall digestibility. Target sites for functional markers were identified enabling development of efficient marker-based selection strategies. PMID:20152036
Al-Harbi, Khalid M.; Almuzaini, Ibrahim S.; Morsy, Mohamed M.; Abdelaziz, Nada A.; Al-Balawi, Alia M.; Abdallah, Atiyeh M.
2015-01-01
Objectives: To investigate the association between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and rheumatic heart disease (RHD) in Saudi patients. Methods: A case-control study was conducted in Saudi RHD patients. Genomic DNA was isolated from 99 RHD patients attending the Pediatric Cardiology Clinic at the Maternity and Children Hospital, Al-Madinah, Saudi Arabia from March 2013 to June 2014, and from 145 age- and gender-matched controls. Patient clinical records were reviewed to report major and minor modified Jones’ criteria for diagnosis. The diagnosis was confirmed by echocardiography. The ACE I/D polymorphism was identified by polymerase chain reaction. Results: A significant difference in ACE D allele carriage (DD+ID) distribution between RHD cases and controls was identified (p=0.02, odds ratio = 3.6, 95% confidence interval: 1.2-10.8). The D allele carriage was significantly associated with development of mitral valve lesions alone (p=0.03). Conclusion: The ACE I/D polymorphism is associated with an increased risk of RHD in the Saudi population. Further studies are needed to confirm our findings and to understand the molecular mechanisms underlying this association. PMID:25719581
Biasin, Mara; Sironi, Manuela; Saulle, Irma; Pontremoli, Chiara; Garziano, Micaela; Cagliani, Rachele; Trabattoni, Daria; Lo Caputo, Sergio; Vichi, Francesca; Mazzotta, Francesco; Forni, Diego; Riva, Stefania; Aguilar-Jimenez, Wbeimar; Cedeño, Samandhy; Sanchez, Jorge; Brander, Christian; Zapata, Wildeman; Rugeles, Maria Teresa; Clerici, Mario
2017-01-01
We investigated whether a 6-amino acid insertion/deletion polymorphism in the mucin domain of TIM-1 (T-cell immunoglobulin and mucin domain 1), modulates susceptibility to HIV-1 infection. The polymorphism was genotyped in three case/control cohorts of HIV-1 exposed seronegative individuals (HESN) and HIV-1 infected subjects from Italy, Peru, and Colombia; data from a Thai population were retrieved from the literature. Across all cohorts, homozygosity for the short TIM-1 allele was more common in HESNs than in HIV-1 infected subjects. A meta-analysis of the four association analyses yielded a p value of 0.005. In vitro infection assays of CD4+ T lymphocytes indicated that homozygosity for the short allele is associated with lower rate of HIV-1 replication. These results suggest that the deletion allele protects from HIV-1 infection with a recessive effect. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.
Altools: a user friendly NGS data analyser.
Camiolo, Salvatore; Sablok, Gaurav; Porceddu, Andrea
2016-02-17
Genotyping by re-sequencing has become a standard approach to estimate single nucleotide polymorphism (SNP) diversity, haplotype structure and the biodiversity and has been defined as an efficient approach to address geographical population genomics of several model species. To access core SNPs and insertion/deletion polymorphisms (indels), and to infer the phyletic patterns of speciation, most such approaches map short reads to the reference genome. Variant calling is important to establish patterns of genome-wide association studies (GWAS) for quantitative trait loci (QTLs), and to determine the population and haplotype structure based on SNPs, thus allowing content-dependent trait and evolutionary analysis. Several tools have been developed to investigate such polymorphisms as well as more complex genomic rearrangements such as copy number variations, presence/absence variations and large deletions. The programs available for this purpose have different strengths (e.g. accuracy, sensitivity and specificity) and weaknesses (e.g. low computation speed, complex installation procedure and absence of a user-friendly interface). Here we introduce Altools, a software package that is easy to install and use, which allows the precise detection of polymorphisms and structural variations. Altools uses the BWA/SAMtools/VarScan pipeline to call SNPs and indels, and the dnaCopy algorithm to achieve genome segmentation according to local coverage differences in order to identify copy number variations. It also uses insert size information from the alignment of paired-end reads and detects potential large deletions. A double mapping approach (BWA/BLASTn) identifies precise breakpoints while ensuring rapid elaboration. Finally, Altools implements several processes that yield deeper insight into the genes affected by the detected polymorphisms. Altools was used to analyse both simulated and real next-generation sequencing (NGS) data and performed satisfactorily in terms of positive predictive values, sensitivity, the identification of large deletion breakpoints and copy number detection. Altools is fast, reliable and easy to use for the mining of NGS data. The software package also attempts to link identified polymorphisms and structural variants to their biological functions thus providing more valuable information than similar tools.
Molecular evolution of bovine Toll-like receptor 2 suggests substitutions of functional relevance.
Jann, Oliver C; Werling, Dirk; Chang, Jung-Su; Haig, David; Glass, Elizabeth J
2008-10-20
There is accumulating evidence that polymorphism in Toll-like receptor (TLR) genes might be associated with disease resistance or susceptibility traits in livestock. Polymorphic sites affecting TLR function should exhibit signatures of positive selection, identified as a high ratio of non-synonymous to synonymous nucleotide substitutions (omega). Phylogeny based models of codon substitution based on estimates of omega for each amino acid position can therefore offer a valuable tool to predict sites of functional relevance. We have used this approach to identify such polymorphic sites within the bovine TLR2 genes from ten Bos indicus and Bos taurus cattle breeds. By analysing TLR2 gene phylogeny in a set of mammalian species and a subset of ruminant species we have estimated the selective pressure on individual sites and domains and identified polymorphisms at sites of putative functional importance. The omega were highest in the mammalian TLR2 domains thought to be responsible for ligand binding and lowest in regions responsible for heterodimerisation with other TLR-related molecules. Several positively-selected sites were detected in or around ligand-binding domains. However a comparison of the ruminant subset of TLR2 sequences with the whole mammalian set of sequences revealed that there has been less selective pressure among ruminants than in mammals as a whole. This suggests that there have been functional changes during ruminant evolution. Twenty newly-discovered non-synonymous polymorphic sites were identified in cattle. Three of them were localised at positions shaped by positive selection in the ruminant dataset (Leu227Phe, His305Pro, His326Gln) and in domains involved in the recognition of ligands. His326Gln is of particular interest as it consists of an exchange of differentially-charged amino acids at a position which has previously been shown to be crucial for ligand binding in human TLR2. Within bovine TLR2, polymorphisms at amino acid positions 227, 305 and 326 map to functionally important sites of TLR2 and should be considered as candidate SNPs for immune related traits in cattle. A final proof of their functional relevance requires further studies to determine their functional effect on the immune response after stimulation with relevant ligands and/or their association with immune related traits in animals.
Bahri, Raoudha; El Moncer, Wifak; Al-Batayneh, Khalid; Sadiq, May; Esteban, Esther; Moral, Pedro; Chaabani, Hassen
2012-05-01
Although much of Jordan is covered by desert, its north-western region forms part of the Fertile Crescent region that had given a rich past to Jordanians. This past, scarcely described by historians, is not yet clarified by sufficient genetic data. Thus in this paper we aim to determine the genetic differentiation of the Jordanian population and to discuss its origin. A total of 150 unrelated healthy Jordanians were investigated for ten Alu insertion polymorphisms. Genetic relationships among populations were estimated by a principal component (PC) plot based on the analyses of the R-matrix software. Statistical analysis showed that the Jordanian population is not significantly different from the United Arab Emirates population or the North Africans. This observation, well represented in PC plot, suggests a common origin of these populations belonging respectively to ancient Mesopotamia, Arabia, and North Africa. Our results are compatible with ancient peoples' movements from Arabia to ancient Mesopotamia and North Africa as proposed by historians and supported by previous genetic results. The original genetic profile of the Jordanian population, very likely Arabian Semitic, has not been subject to significant change despite the succession of several civilizations.
Multilocus patterns of polymorphism and selection across the X chromosome of Caenorhabditis remanei.
Cutter, Asher D
2008-03-01
Natural selection and neutral processes such as demography, mutation, and gene conversion all contribute to patterns of polymorphism within genomes. Identifying the relative importance of these varied components in evolution provides the principal challenge for population genetics. To address this issue in the nematode Caenorhabditis remanei, I sampled nucleotide polymorphism at 40 loci across the X chromosome. The site-frequency spectrum for these loci provides no evidence for population size change, and one locus presents a candidate for linkage to a target of balancing selection. Selection for codon usage bias leads to the non-neutrality of synonymous sites, and despite its weak magnitude of effect (N(e)s approximately 0.1), is responsible for profound patterns of diversity and divergence in the C. remanei genome. Although gene conversion is evident for many loci, biased gene conversion is not identified as a significant evolutionary process in this sample. No consistent association is observed between synonymous-site diversity and linkage-disequilibrium-based estimators of the population recombination parameter, despite theoretical predictions about background selection or widespread genetic hitchhiking, but genetic map-based estimates of recombination are needed to rigorously test for a diversity-recombination relationship. Coalescent simulations also illustrate how a spurious correlation between diversity and linkage-disequilibrium-based estimators of recombination can occur, due in part to the presence of unbiased gene conversion. These results illustrate the influence that subtle natural selection can exert on polymorphism and divergence, in the form of codon usage bias, and demonstrate the potential of C. remanei for detecting natural selection from genomic scans of polymorphism.
Wang, Pei; Lu, Yanli; Zheng, Mingmin; Rong, Tingzhao; Tang, Qilin
2011-01-01
Genetic relationship of a newly discovered teosinte from Nicaragua, Zea nicaraguensis with waterlogging tolerance, was determined based on randomly amplified polymorphic DNA (RAPD) markers and the internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA using 14 accessions from Zea species. RAPD analysis showed that a total of 5,303 fragments were produced by 136 random decamer primers, of which 84.86% bands were polymorphic. RAPD-based UPGMA analysis demonstrated that the genus Zea can be divided into section Luxuriantes including Zea diploperennis, Zea luxurians, Zea perennis and Zea nicaraguensis, and section Zea including Zea mays ssp. mexicana, Zea mays ssp. parviglumis, Zea mays ssp. huehuetenangensis and Zea mays ssp. mays. ITS sequence analysis showed the lengths of the entire ITS region of the 14 taxa in Zea varied from 597 to 605 bp. The average GC content was 67.8%. In addition to the insertion/deletions, 78 variable sites were recorded in the total ITS region with 47 in ITS1, 5 in 5.8S, and 26 in ITS2. Sequences of these taxa were analyzed with neighbor-joining (NJ) and maximum parsimony (MP) methods to construct the phylogenetic trees, selecting Tripsacum dactyloides L. as the outgroup. The phylogenetic relationships of Zea species inferred from the ITS sequences are highly concordant with the RAPD evidence that resolved two major subgenus clades. Both RAPD and ITS sequence analyses indicate that Zea nicaraguensis is more closely related to Zea luxurians than the other teosintes and cultivated maize, which should be regarded as a section Luxuriantes species. PMID:21525982
Kim, Hye Young; Eyheramonho, María Belén; Pichavant, Muriel; Gonzalez Cambaceres, Carlos; Matangkasombut, Ponpan; Cervio, Guillermo; Kuperman, Silvina; Moreiro, Rita; Konduru, Krishnamurthy; Manangeeswaran, Mohanraj; Freeman, Gordon J.; Kaplan, Gerardo G.; DeKruyff, Rosemarie H.; Umetsu, Dale T.; Rosenzweig, Sergio D.
2011-01-01
During infection with the hepatitis A virus (HAV), most patients develop mild or asymptomatic disease. However, a small number of patients develop serious, life-threatening hepatitis. We investigated this variability in disease severity by examining 30 Argentinean patients with HAV-induced acute liver failure in a case-control, cross-sectional, observational study. We found that HAV-induced severe liver disease was associated with a 6-amino-acid insertion in TIM1/HAVCR1 (157insMTTTVP), the gene encoding the HAV receptor. This polymorphism was previously shown to be associated with protection against asthma and allergic diseases and with HIV progression. In binding assays, the TIM-1 protein containing the 157insMTTTVP insertion polymorphism bound HAV more efficiently. When expressed by human natural killer T (NKT) cells, this long form resulted in greater NKT cell cytolytic activity against HAV-infected liver cells, compared with the shorter TIM-1 protein without the polymorphism. To our knowledge, the 157insMTTTVP polymorphism in TIM1 is the first genetic susceptibility factor shown to predispose to HAV-induced acute liver failure. Furthermore, these results suggest that HAV infection has driven the natural selection of shorter forms of the TIM-1 protein, which binds HAV less efficiently, thereby protecting against severe HAV-induced disease, but which may predispose toward inflammation associated with asthma and allergy. PMID:21339644
Hook, Ch D; Samsonov, V V; Ublinskaya, A A; Kuvaeva, T M; Andreeva, E V; Gorbacheva, L Yu; Stoynova, N V
2016-11-01
Despite the abundance of genetic manipulation approaches, particularly for Escherichia coli, new techniques and increased flexibility in the application of existing techniques are required to address novel aims. The most widely used approaches for chromosome editing are based on bacteriophage site-specific and λRed/RecET-mediated homologous recombination. In the present study, these techniques were combined to develop a novel approach for in vivo cloning and targeted long-length chromosomal insertion. This approach permits direct λRed-mediated cloning of DNA fragment with lengths of 10kb or greater from the E. coli chromosome into the plasmid vector pGL2, which carries the ori of pSC101, the ϕ80-attP site of ϕ80 phage, and an excisable Cm R marker bracketed by λ-attL/attR sites. In pGL2-based recombinant plasmids, the origin of replication can be eliminated in vitro via hydrolysis by SceI endonuclease and recircularization by DNA ligase. The resulting ori-less circular recombinant DNA can be used for targeted insertion of the cloned sequence into the chromosome at a selected site via ϕ80 phage-specific integrase-mediated recombination using the Dual-In/Out approach (Minaeva et al., 2008). At the final stage of chromosomal editing, the Cm R -marker can be excised from the chromosome due to expression of the λint/xis genes. Notably, the desired fragment can be inserted as multiple copies in the chromosome by combining insertions at different sites in one strain using the P1 general transduction technique (Moore, 2011). The developed approach is useful for the construction of plasmidless, markerless recombinant strains for fundamental and industrial purposes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Esteller, M.; GarcÃa, A.; MartÃnez-Palones, J. M.; Xercavins, J.; Reventós, J.
1997-01-01
A case-control study was designed to identify associations between polymorphisms at p53, cytochrome P-450 (CYP1A1) and glutathione-S-transferases and endometrial cancer susceptibility. Among all polymorphisms analysed, an insertional variant in p53 (P53PIN3) and two polymorphisms in the 3'-end and exon 7 of CYP1A1 showed significant association with enhanced endometrial cancer risk. Images Figure 1 Figure 2 PMID:9155064
Hjelm, L N; Branstrom, A A; Warren, R L
1990-01-01
An 800-base-pair HindIII-PstI fragment that flanks a hot spot for Tn7 insertion was isolated from the chromosome of Pseudomonas aeruginosa and cloned into pUC12. The fragment was used to probe XhoI digests of genomic DNA from 18 P. aeruginosa isolates collected from sputum samples of seven cystic fibrosis patients. Only two XhoI restriction fragment length polymorphisms (RFLPs), of 3.7 and 7.7 kilobases (kb), were detected. Isolate WSU3531-1 (3.7-kb XhoI fragment) and WSU3860 (7.7-kb XhoI fragment), while isolated from the same patient, showed different RFLPs. Serial passages of isolate WSU3531-1 demonstrated that this strain was phenotypically stable. In contrast, colony and pigment variants were readily isolated at a frequency of 1% from serial passages of isolate WSU3860. When XhoI-digested genomic DNA from phenotypic variants of serially passaged WSU3860 were probed with the 800-base-pair HindIII-PstI fragment, the probe hybridized to a 10.4-kb XhoI fragment from three isolates. Restriction analysis of the genomic DNA digested with a variety of restriction enzymes showed that a 2.7-kb insertion occurred in the same region for all three isolates. There appeared to be no correlation between changes in the RFLP and changes in colony morphology. Images PMID:1977762
Domb, Katherine; Keidar, Danielle; Yaakov, Beery; Khasdan, Vadim; Kashkush, Khalil
2017-10-27
Natural populations of the tetraploid wild emmer wheat (genome AABB) were previously shown to demonstrate eco-geographically structured genetic and epigenetic diversity. Transposable elements (TEs) might make up a significant part of the genetic and epigenetic variation between individuals and populations because they comprise over 80% of the wild emmer wheat genome. In this study, we performed detailed analyses to assess the dynamics of transposable elements in 50 accessions of wild emmer wheat collected from 5 geographically isolated sites. The analyses included: the copy number variation of TEs among accessions in the five populations, population-unique insertional patterns, and the impact of population-unique/specific TE insertions on structure and expression of genes. We assessed the copy numbers of 12 TE families using real-time quantitative PCR, and found significant copy number variation (CNV) in the 50 wild emmer wheat accessions, in a population-specific manner. In some cases, the CNV difference reached up to 6-fold. However, the CNV was TE-specific, namely some TE families showed higher copy numbers in one or more populations, and other TE families showed lower copy numbers in the same population(s). Furthermore, we assessed the insertional patterns of 6 TE families using transposon display (TD), and observed significant population-specific insertional patterns. The polymorphism levels of TE-insertional patterns reached 92% among all wild emmer wheat accessions, in some cases. In addition, we observed population-specific/unique TE insertions, some of which were located within or close to protein-coding genes, creating allelic variations in a population-specific manner. We also showed that those genes are differentially expressed in wild emmer wheat. For the first time, this study shows that TEs proliferate in wild emmer wheat in a population-specific manner, creating new alleles of genes, which contribute to the divergent evolution of homeologous genes from the A and B subgenomes.
Erdemir, Aysegul; Mutlu, Ozal
2017-06-01
Lactate dehydrogenase (LDH) is an important metabolic enzyme in glycolysis and it has been considered as the main energy source in many organisms including apicomplexan parasites. Differences at the active site loop of the host and parasite LDH's makes this enzyme an attractive target for drug inhibitors. In this study, five amino acid insertions in the active site pocket of Theileria annulata LDH (TaLDH) were deleted by PCR-based site-directed mutagenesis, expression and activity analysis of mutant and wild type TaLDH enzymes were performed. Removal of the insertion at the active site loop caused production of an inactive enzyme. Furthermore, structures of wild and mutant enzymes were predicted by comparative modeling and the importance of the insertions at the active site loop were also assigned by molecular docking and dynamics simulations in order to evaluate essential role of this loop for the enzymatic activity. Pentapeptide insertion removal resulted in loss of LDH activity due to deletion of Trp96 and conformational change of Arg98 because of loop instability. Analysis of wild type and mutant enzymes with comparative molecular dynamics simulations showed that the fluctuations of the loop residues increase in mutant enzyme. Together with in silico studies, in vitro results revealed that active site loop has a vital role in the enzyme activity and our findings promise hope for the further drug design studies against theileriosis and other apicomplexan parasite diseases. Copyright © 2017 Elsevier Inc. All rights reserved.
Masud, Rizwan; Qureshi, Irfan Zia
2011-09-01
Cardiovascular disorders and coronary artery disease (CAD) are significant contributors to morbidity and mortality in heart patients. As genes of the folate/homocysteine pathway have been linked with the vascular disease, we investigated association of these gene polymorphisms with CAD/myocardial infarction (MI) using the novel approach of tetraprimer ARMS-PCR. A total of 230 participants (129 MI cases, 101 normal subjects) were recruited. We genotyped rs1801133 and rs1801131 SNPs in 5'10' methylenetetrahydrofolate reductase (MTHFR), rs1805087 SNP in 5' methyltetrahydrofolate homocysteine methyltransferase (MTR), rs662 SNP in paroxanse1 (PON1), and rs5742905 polymorphism in cystathionine beta synthase (CBS). Angiotensin converting enzyme (ACE) insertion/deletion polymorphism was detected through conventional PCR. Covariates included blood pressure, fasting blood sugar, serum cholesterol, and creatinine concentrations. Our results showed allele frequencies at rs1801133, rs1801131, rs1805087 and the ACE insertion/deletion (I/D) polymorphism varied between cases and controls. Logistic regression, after adjusting for covariates, demonstrated significant associations of rs1801133 and rs1805087 with CAD in the additive, dominant, and genotype model. In contrast, ACE I/D polymorphism was significantly related with CAD where recessive model was applied. Gene-gene interaction against the disease status revealed two polymorphism groups: rs1801133, rs662, and rs1805087; and rs1801131, rs662, and ACE I/D. Only the latter interaction maintained significance after adjusted for covariates. Our study concludes that folate pathway variants exert contributory influence on susceptibility to CAD. We further suggest that tetraprimer ARMS-PCR successfully resolves the genotypes in selected samples and might prove to be a superior technique compared to the conventional approach.
Kiss, István; Kiss, Zoltán; Kerkovits, Lóránt; Paksy, András; Ambrus, Csaba
2017-01-01
The relationship between smoking and mortality in patients on hemodialysis is controversial. Earlier studies showed that the insertion/deletion (I/D) polymorphism of the ACE gene might have an effect on mortality. The aim of this study was to test the impact of smoking on survival and whether this association was influenced by ACE gene I/D polymorphism in patients on maintenance hemodialysis. In this prospective, multicenter cohort study we analyzed 709 prevalent patients on maintenance hemodialysis. Patients were allocated into groups based on their smoking habit. Outcome data were collected during the 144-month follow-up period. Outcomes of current smokers and lifelong non-smokers were compared. In order to control for interactions between predictor variables, we also identified 160 matched pairs for further sub-analysis. The vast majority of patients (67%) were non-smokers, followed by current smokers (22.2%) and ex-smokers (9.8%). Smoking had no impact on survival in the matched pair analysis ( p = 0.99). After adjustment for ACE I/D polymorphism and other co-variates, smoking had no effect on survival. Our data suggest that smoking has no impact on survival; neither is it associated with ACE gene I/D polymorphism in hemodialysis patients.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trask, B.J.; Friedman, C.; Giorgi, D.
1994-09-01
We have discovered a large DNA segment that is polymorphically present at the ends of several human chromosomes. The segment, f7501, was originally derived form a human chromosome 19-specific cosmid library. FISH was used to determine the cosmid`s chromosomal distribution on 44 unrelated humans and several closely related primates. The human subjects represent a diversity of reproductively isolated ethnic populations. FISH analysis revealed that sequences highly homologous to the cosmid`s insert are present on both homologs at 3q, 15q,. and 19p in almost all individuals (88, 85, and 87 of 88 homologs, respectively). Other chromosomes sites were labeled much moremore » rarely in the sampled individuals. For example, 56 of the 88 analyzed chromosomes 11 were labeled (18+/+, 6-/-, and 20+/- individuals). In contrast, 2q was labeled on only 1/88 sampled chromosomes. The termini of 2q, 5q, 6p, 6q, 7p, 8p, 9p, 9q, 11p, 12q, 16p, 19q, and 20q and an interstitial site at 2q13-14 were labeled in at least one individual of the set. EcoR1-fragments derived from the cosmid showed the same hybridization pattern as the entire cosmid, indicating that at least 40 kbp is shared by these chromosome ends. Ethnic differences in the allele frequency of these polymorphic variants was observed. For example, signals were observed on 8/10 and 7/10 of the chromosomes 7p and 16q, respectively, derived form Biakan Pygmies, but these sites were infrequently labeled in non-Pygmy human populations (2/68, respectively). This region has undergone significant changes in chromosome location during human evolution. Strong signal was seen on chimpanzee and gorilla chromosome 3, which is homologous to human chromosome 4, a chromosome unlabeled in any of the humans we have analyzed.« less
Carvalho, Darlen C; Wanderley, Alayde V; Amador, Marcos A T; Fernandes, Marianne R; Cavalcante, Giovanna C; Pantoja, Karla B C C; Mello, Fernando A R; de Assumpção, Paulo P; Khayat, André S; Ribeiro-Dos-Santos, Ândrea; Santos, Sidney; Dos Santos, Ney P C
2015-08-20
Acute lymphoblastic leukemia (ALL) is a malignant tumor common in children. Studies of genetic susceptibility to cancer using biallelic insertion/deletion (INDEL) type polymorphisms associated with cancer development pathways may help to clarify etymology of ALL. In this study, we investigate the role of eight functional INDEL polymorphisms and influence of genetic ancestry to B-cell ALL susceptibility in children of Brazilian Amazon population, which has a high degree of inter-ethnic admixture. Ancestry analysis was estimated using a panel of 48 autosomal ancestry informative markers. 130 B-cell ALL patients and 125 healthy controls were included in this study. The odds ratios and 95% confidence intervals were adjusted for confounders. The results indicated an association between the investigated INDEL polymorphisms in CASP8 (rs3834129), CYP19A1 (rs11575899) e XRCC1 (rs3213239) genes in the development of B-cell ALL. The carriers of Insertion/Insertion (Ins/Ins) genotype of the polymorphism in CASP8 gene presented reduced chances of developing B-cell ALL (P=0.001; OR=0.353; 95% CI=0.192-0.651). The Deletion/Deletion (Del/Del) genotype of the polymorphism in CYP19A1 gene was associated to a lower chance of developing B-cell ALL (P=3.35×10 -6 ; OR=0.121; 95% CI=0.050-0.295), while Del/Del genotype of the polymorphism in XRCC1 gene was associated to a higher chance of developing B-cell ALL (P=2.01×10 -4 ; OR=6.559; 95% CI=2.433-17.681). We also found that Amerindian ancestry correlates with the risk of B-cell ALL. For each increase of 10% in the Amerindian ancestry results in 1.4-fold chances of developing B-cell ALL (OR=1.406; 95% IC=1.123-1.761), while each increase of 10% in the European ancestry presents a protection effect in the development of B-cell ALL (OR=0.666; 95% IC=0.536-0.827). The results suggest that genetic factors influence leukemogenesis and might be explored in the stratification of B-cell ALL risk in admixed populations. Copyright © 2015 Z. Published by Elsevier Ltd.. All rights reserved.
Genome-wide analysis of Tol2 transposon reintegration in zebrafish.
Kondrychyn, Igor; Garcia-Lecea, Marta; Emelyanov, Alexander; Parinov, Sergey; Korzh, Vladimir
2009-09-08
Tol2, a member of the hAT family of transposons, has become a useful tool for genetic manipulation of model animals, but information about its interactions with vertebrate genomes is still limited. Furthermore, published reports on Tol2 have mainly been based on random integration of the transposon system after co-injection of a plasmid DNA harboring the transposon and a transposase mRNA. It is important to understand how Tol2 would behave upon activation after integration into the genome. We performed a large-scale enhancer trap (ET) screen and generated 338 insertions of the Tol2 transposon-based ET cassette into the zebrafish genome. These insertions were generated by remobilizing the transposon from two different donor sites in two transgenic lines. We found that 39% of Tol2 insertions occurred in transcription units, mostly into introns. Analysis of the transposon target sites revealed no strict specificity at the DNA sequence level. However, Tol2 was prone to target AT-rich regions with weak palindromic consensus sequences centered at the insertion site. Our systematic analysis of sequential remobilizations of the Tol2 transposon from two independent sites within a vertebrate genome has revealed properties such as a tendency to integrate into transcription units and into AT-rich palindrome-like sequences. This information will influence the development of various applications involving DNA transposons and Tol2 in particular.
Guo, Bingfu; Guo, Yong; Hong, Huilong; Qiu, Li-Juan
2016-01-01
Molecular characterization of sequence flanking exogenous fragment insertion is essential for safety assessment and labeling of genetically modified organism (GMO). In this study, the T-DNA insertion sites and flanking sequences were identified in two newly developed transgenic glyphosate-tolerant soybeans GE-J16 and ZH10-6 based on whole genome sequencing (WGS) method. More than 22.4 Gb sequence data (∼21 × coverage) for each line was generated on Illumina HiSeq 2500 platform. The junction reads mapped to boundaries of T-DNA and flanking sequences in these two events were identified by comparing all sequencing reads with soybean reference genome and sequence of transgenic vector. The putative insertion loci and flanking sequences were further confirmed by PCR amplification, Sanger sequencing, and co-segregation analysis. All these analyses supported that exogenous T-DNA fragments were integrated in positions of Chr19: 50543767-50543792 and Chr17: 7980527-7980541 in these two transgenic lines. Identification of genomic insertion sites of G2-EPSPS and GAT transgenes will facilitate the utilization of their glyphosate-tolerant traits in soybean breeding program. These results also demonstrated that WGS was a cost-effective and rapid method for identifying sites of T-DNA insertions and flanking sequences in soybean.
Kalotra, V; Lall, M; Verma, I C; Kaur, A; Kaur, A
2018-03-01
HLA-G, a nonclassical class-Ib gene is mainly expressed on extravillous trophoblasts at the fetal-maternal interface. HLA-G molecule is considered to play an important role in maternal immune suppression during pregnancy. The 14 bp insertion/deletion polymorphism (rs66554220) in exon eight of the HLA-G gene influences HLA-G mRNA stability and isoform splicing patterns. In this study, 202 recurrent miscarriage (RM) women with two or more than two consecutive miscarriages, their 202 partners and 204 fertile control women with at least one live birth and no miscarriages were analyzed for 14 bp insertion/deletion polymorphism. Soluble HLA-G (sHLA-G) levels were also determined and compared between randomly selected 111 RM women and 111 control women using QAYEE-Bio ELISA kits. Student's t test and χ 2 test were used to depict the statistical differences. The results showed no significant differences for 14 bp allele and genotype frequencies between the study groups. However, our study showed a significant difference (P = .0107) for sHLA-G levels in RM women and control women. Furthermore, a significant difference (P = .0135) for sHLA-G levels in relation to +/-14 bp heterozygous genotype was seen between the two groups. The 14 bp allele sharing between the partners did not show any significant association with the number of miscarriages in RM couples. The association of 14 bp polymorphism and recurrent miscarriages was not significant in our study. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Griffith, A.J.; Burgess, D.L.; Kohrman, D.
1994-09-01
The Twirler mutation (Tw) causing cleft palate {plus_minus} cleft lip, vestibular defects and obesity is located within 0.5 cM of an ataxia locus (ax) on mouse chromosome 18. We identified a transgene-induced insertional mutation with vestibular and craniofacial defects that appears to be a new allele of Twirler. Mouse DNA flanking the transgene insertion site was isolated from a cosmid library. An evolutionarily conserved, zoo blot positive cosmid subclone was used to probe a human {lambda} genomic library. From the sequence of a highly homologous human {lambda} clone, we designed STS primers and screened a human P1 library. DNA frommore » two positive P1 clones was hybridized with simple sequence probes, and a (CTAT){sub 12} repeat was detected. Analysis of 62 CEPH parents with primers flanking the repeat identified six alleles containing 9 to 14 copies of the repeat, at frequencies of 0.17, 0.17, 0.17, 0.27, 0.15 and 0.07, respectively. The observed heterozygosity was 49/62 with a calculated PIC value of 0.76. This polymorphic microsatellite marker, designated Umi3, was mapped to the predicted conserved human linkage group by analysis of somatic cell hybrid panels. The anticipated short distance between Umi3 and the disease genes will facilitate detection of linkage in small families. We would like to type appropriate human pedigrees with Umi3 in order to identify patients with inherited disorders homologous to the mouse mutations Twirler and ataxia.« less
Morsy, Mohamed-Mofeed Fawaz; Abdelaziz, Nada Abdelmohsen Mohamed; Boghdady, Ahmed Mohamed; Ahmed, Hydi; Abu Elfadl, Essam Mohamed; Ismail, Mohamed Ali
2011-01-01
Angiotensin converting enzyme (ACE) gene polymorphism was previously studied in some cardiovascular diseases. There are only few studies which investigated this polymorphism in patients with rheumatic heart disease (RHD). The results of these investigations are inconsistent. Furthermore, gene polymorphism distribution is different in various ethnic populations. We conducted this study to demonstrate this gene polymorphism in Egyptian children with RHD. Leukocytes DNA was extracted from 139 patients with RHD and 79 healthy control children. After amplification by the PCR, the products were separated by electrophoresis in 6% polyacrylamide gel and visualized after ethidium bromide staining with UV light. The PCR product is a 190-bp fragment in the absence of the insertion (D allele) and a 490-bp fragment in the presence of the insertion (I allele). Gene polymorphism was as follows: DD gene when lane contains only 190-bp fragment, II gene when lane contains only 490-bp fragment and ID gene when lane contains both fragments. We found that gene polymorphism in both control and patients groups followed the following order of distribution from highest to lowest: ID, II, DD gene. The frequency in control group was 49.4, 36.7, and 13.9%, respectively. In patients groups, the gene frequency was 42.5, 30.9, and 26.6%, respectively. DD gene frequency differs significantly between the two groups. We concluded that patients with RHD have a higher ACE-DD genotype than normal control. ACE-DD genotype may be a risk factor for RHD in Egyptian children.
Angiotensin converting enzyme insertion/deletion polymorphism: association with ethnic origin.
Barley, J; Blackwood, A; Carter, N D; Crews, D E; Cruickshank, J K; Jeffery, S; Ogunlesi, A O; Sagnella, G A
1994-08-01
To determine the distribution of the insertion/deletion (I/D) polymorphism of the angiotensin converting enzyme (ACE) gene in several ethnic groups: Caucasian Europeans, Black Nigerians, Samoan Polynesians and Yanomami Indians. The ratio of the frequencies of the II, ID and DD genotypes were 1:2:1 in the Europeans, but there was a tendency towards a higher frequency of the D allele in the Nigerians. In contrast, the Samoans and the Yanomami Indians displayed a much higher frequency of the I allele than of the D allele. The relationship between ACE genotype and disease in these latter groups is still not known, but the present results clearly suggest that ethnic origin should be carefully considered in the increasing number of studies on the association between I/D ACE genotype and disease aetiology.
Marsh, Terence L.; Saxman, Paul; Cole, James; Tiedje, James
2000-01-01
Rapid analysis of microbial communities has proven to be a difficult task. This is due, in part, to both the tremendous diversity of the microbial world and the high complexity of many microbial communities. Several techniques for community analysis have emerged over the past decade, and most take advantage of the molecular phylogeny derived from 16S rRNA comparative sequence analysis. We describe a web-based research tool located at the Ribosomal Database Project web site (http://www.cme.msu.edu/RDP/html/analyses.html) that facilitates microbial community analysis using terminal restriction fragment length polymorphism of 16S ribosomal DNA. The analysis function (designated TAP T-RFLP) permits the user to perform in silico restriction digestions of the entire 16S sequence database and derive terminal restriction fragment sizes, measured in base pairs, from the 5′ terminus of the user-specified primer to the 3′ terminus of the restriction endonuclease target site. The output can be sorted and viewed either phylogenetically or by size. It is anticipated that the site will guide experimental design as well as provide insight into interpreting results of community analysis with terminal restriction fragment length polymorphisms. PMID:10919828
Thermodynamic impact of abasic sites on simulated translesion DNA synthesis.
Malina, Jaroslav; Brabec, Viktor
2014-06-16
Loss of a base in DNA and the creation of an abasic (apurinic/apyrimidinic, AP) site is a frequent lesion that may occur spontaneously, or as a consequence of the action of DNA-damaging agents. The AP lesion is mutagenic or lethal if not repaired. We report a systematic thermodynamic investigation by differential scanning calorimetry on the evolution, during primer extension, of a model AP site in chemically simulated DNA translesion synthesis. Incorporation of dAMP (deoxyadenosine monophosphate), as well as dTMP (deoxythymidine monophosphate), opposite an AP site is enthalpically unfavorable, although incorporation of dTMP is more enthalpically unfavorable than that of dAMP. This finding is in a good agreement with experimental data showing that AP sites block various DNA polymerases of eukaryotic and prokaryotic origin and that, if bypassed, dAMP is preferentially inserted, whereas insertion of dTMP is less likely. The results emphasize the importance of thermodynamic contributions to the insertion of nucleotides opposite an AP site by DNA polymerases. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Reshetnikov, Evgeny A; Akulova, Ludmila Y; Dobrodomova, Irina S; Dvornyk, Volodymyr Y; Polonikov, Alexey V; Churnosov, Mikhail I
2015-09-01
Malfunctioning of the cardiovascular system during pregnancy may be responsible for adverse effects on the 'mother-fetus' system. The cardiovascular system of a pregnant woman develops adaptation to the increased load. Angiotensin-converting enzyme (ACE) is known to play an important role in the adaptation. The present study was designed to investigate whether the insertion-deletion (I/D) polymorphism of the ACE gene is associated with the level of arterial blood pressure in women before and during pregnancy. The level of blood pressure was measured in 591 Russian women (Central Russia) before and during (37-40 weeks term) pregnancy. The women were divided into three groups which were hypertensive, hypotensive, and normotensive according to blood pressure level. Genotyping of the ACE I/D polymorphism was performed using polymerase chain reaction (PCR) and amplified fragment length polymorphism assay. Women with genotype DD showed the highest blood pressure level both during and at the end of pregnancy (p<0.05). The highest frequencies of allele D and genotype DD were found in pregnant women in the hypertensive group. The deletion variant of the ACE gene is associated with high blood pressure level at the end of pregnancy. © The Author(s) 2013.
Vukich, M; Schulman, A H; Giordani, T; Natali, L; Kalendar, R; Cavallini, A
2009-10-01
The inter-retrotransposon amplified polymorphism (IRAP) protocol was applied for the first time within the genus Helianthus to assess intraspecific variability based on retrotransposon sequences among 36 wild accessions and 26 cultivars of Helianthus annuus L., and interspecific variability among 39 species of Helianthus. Two groups of LTRs, one belonging to a Copia-like retroelement and the other to a putative retrotransposon of unknown nature (SURE) have been isolated, sequenced and primers were designed to obtain IRAP fingerprints. The number of polymorphic bands in H. annuus wild accessions is as high as in Helianthus species. If we assume that a polymorphic band can be related to a retrotransposon insertion, this result suggests that retrotransposon activity continued after Helianthus speciation. Calculation of similarity indices from binary matrices (Shannon's and Jaccard's indices) show that variability is reduced among domesticated H. annuus. On the contrary, similarity indices among Helianthus species were as large as those observed among wild H. annuus accessions, probably related to their scattered geographic distribution. Principal component analysis of IRAP fingerprints allows the distinction between perennial and annual Helianthus species especially when the SURE element is concerned.
Mateus Pereira, L H; Socorro, A; Fernandez, I; Masleh, M; Vidal, D; Bianchi, N O; Bonatto, S L; Salzano, F M; Herrera, R J
2005-09-01
This study attempts to ascertain genetic affinities between Native American and East Asian populations by analyzing four polymorphic Alu insertions (PAIs) and three L1 polymorphic loci. These two genetic systems demonstrated strong congruence when levels of diversity and genetic distances were considered. Overall, genetic relatedness within Native American groups does not correlate with geographical and linguistic structure, although strong grouping for Native Americans with East Asians was demonstrated, with clear discrimination from African and European groups. Most of the variation was assigned to differences occurring within groups, but the interpopulation variation found for South Amerindians was recognizably higher in comparison to the other sampled groups of populations. Our data suggest that bottleneck events followed by strong influence of genetic drift in the process of the peopling of the Americas may have been determinant factors in delineating the genetic background of present-day South Amerindians. Since no clear subgroups were detected within Native Americans and East Asians, there is no indication of multiple waves in the early colonization of the New World. (c) 2005 Wiley-Liss, Inc.
Codon 219 polymorphism of PRNP in healthy caucasians and Creutzfeldt-Jakob disease patients
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petraroli, R.; Pocchiari, M.
1996-04-01
A number of point and insert mutations of the PrP gene (PRNP) have been linked to familial Creutzfeldt-Jakob disease (CJD) and Gerstmann-Straussler-Scheinker disease (GSS). Moreover, the methionine/valine homozygosity at the polymorphic codon 129 of PRNP may cause a predisposition to sporadic and iatrogenic CJD or may control the age at onset of familial cases carrying either the 144-bp insertion or codon 178, codon 198, and codon 210 pathogenic mutations in PRNP. In addition, the association of methionine or valine at codon 129 and the point mutation at codon 178 on the same allele seem to play an important role inmore » determining either fatal familial insomnia or CJD. However, it is noteworthy that a relationship between codon 129 polymorphism and accelerated pathogenesis (early age at onset or shorter duration of the disease) has not been seen in familial CJD patients with codon 200 mutation or in GSS patients with codon 102 mutation, arguing that other, as yet unidentified, gene products or environmental factors, or both, may influence the clinical expression of these diseases. 17 refs.« less
Lin, Chin; Yang, Hsin-Yi; Wu, Chia-Chao; Lee, Herng-Sheng; Lin, Yuh-Feng; Lu, Kuo-Cheng; Chu, Chi-Ming; Lin, Fu-Huang; Kao, Sen-Yeong; Su, Sui-Lung
2014-01-01
Background Associations between angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphisms and chronic kidney disease (CKD) have been extensively studied, with most studies reporting that individuals with the D allele have a higher risk. Although some factors, such as ethnicity, may moderate the association between ACE I/D polymorphisms and CKD risk, gender-dependent effects on the CKD risk remain controversial. Objectives This study investigated the gender-dependent effects of ACE I/D polymorphisms on CKD risk. Data sources PubMed, the Cochrane library, and EMBASE were searched for studies published before January 2013. Study eligibility criteria, participants, and interventions Cross-sectional surveys and case–control studies analyzing ACE I/D polymorphisms and CKD were included. They were required to match the following criteria: age >18 years, absence of rare diseases, and Asian or Caucasian ethnicity. Study appraisal and synthesis methods The effect of carrying the D allele on CKD risk was assessed by meta-analysis and meta-regression using random-effects models. Results Ethnicity [odds ratio (OR): 1.24; 95% confidence interval (CI): 1.08–1.42] and hypertension (OR: 1.55; 95% CI: 1.04–2.32) had significant moderate effects on the association between ACE I/D polymorphisms and CKD risk, but they were not significant in the diabetic nephropathy subgroup. Males had higher OR for the association between ACE I/D polymorphisms and CKD risk than females in Asians but not Caucasians, regardless of adjustment for hypertension (p<0.05). In subgroup analyses, this result was significant in the nondiabetic nephropathy group. Compared with the I allele, the D allele had the highest risk (OR: 3.75; 95% CI: 1.84–7.65) for CKD in hypertensive Asian males. Conclusions and implications of key findings The ACE I/D polymorphisms may incur the highest risk for increasing CKD in hypertensive Asian males. PMID:24498151
How and how much does RAD-seq bias genetic diversity estimates?
Cariou, Marie; Duret, Laurent; Charlat, Sylvain
2016-11-08
RAD-seq is a powerful tool, increasingly used in population genomics. However, earlier studies have raised red flags regarding possible biases associated with this technique. In particular, polymorphism on restriction sites results in preferential sampling of closely related haplotypes, so that RAD data tends to underestimate genetic diversity. Here we (1) clarify the theoretical basis of this bias, highlighting the potential confounding effects of population structure and selection, (2) confront predictions to real data from in silico digestion of full genomes and (3) provide a proof of concept toward an ABC-based correction of the RAD-seq bias. Under a neutral and panmictic model, we confirm the previously established relationship between the true polymorphism and its RAD-based estimation, showing a more pronounced bias when polymorphism is high. Using more elaborate models, we show that selection, resulting in heterogeneous levels of polymorphism along the genome, exacerbates the bias and leads to a more pronounced underestimation. On the contrary, spatial genetic structure tends to reduce the bias. We confront the neutral and panmictic model to "ideal" empirical data (in silico RAD-sequencing) using full genomes from natural populations of the fruit fly Drosophila melanogaster and the fungus Shizophyllum commune, harbouring respectively moderate and high genetic diversity. In D. melanogaster, predictions fit the model, but the small difference between the true and RAD polymorphism makes this comparison insensitive to deviations from the model. In the highly polymorphic fungus, the model captures a large part of the bias but makes inaccurate predictions. Accordingly, ABC corrections based on this model improve the estimations, albeit with some imprecisions. The RAD-seq underestimation of genetic diversity associated with polymorphism in restriction sites becomes more pronounced when polymorphism is high. In practice, this means that in many systems where polymorphism does not exceed 2 %, the bias is of minor importance in the face of other sources of uncertainty, such as heterogeneous bases composition or technical artefacts. The neutral panmictic model provides a practical mean to correct the bias through ABC, albeit with some imprecisions. More elaborate ABC methods might integrate additional parameters, such as population structure and selection, but their opposite effects could hinder accurate corrections.
Novel insertion mutation of ABCB1 gene in an ivermectin-sensitive Border Collie.
Han, Jae-Ik; Son, Hyoung-Won; Park, Seung-Cheol; Na, Ki-Jeong
2010-12-01
P-glycoprotein (P-gp) is encoded by the ABCB1 gene and acts as an efflux pump for xenobiotics. In the Border Collie, a nonsense mutation caused by a 4-base pair deletion in the ABCB1 gene is associated with a premature stop to P-gp synthesis. In this study, we examined the full-length coding sequence of the ABCB1 gene in an ivermectin-sensitive Border Collie that lacked the aforementioned deletion mutation. The sequence was compared to the corresponding sequences of a wild-type Beagle and seven ivermectin-tolerant family members of the Border Collie. When compared to the wild-type Beagle sequence, that of the ivermectin-sensitive Border Collie was found to have one insertion mutation and eight single nucleotide polymorphisms (SNPs) in the coding sequence of the ABCB1 gene. While the eight SNPs were also found in the family members' sequences, the insertion mutation was found only in the ivermectin-sensitive dog. These results suggest the possibility that the SNPs are species-specific features of the ABCB1 gene in Border Collies, and that the insertion mutation may be related to ivermectin intolerance.
Novel insertion mutation of ABCB1 gene in an ivermectin-sensitive Border Collie
Han, Jae-Ik; Son, Hyoung-Won; Park, Seung-Cheol
2010-01-01
P-glycoprotein (P-gp) is encoded by the ABCB1 gene and acts as an efflux pump for xenobiotics. In the Border Collie, a nonsense mutation caused by a 4-base pair deletion in the ABCB1 gene is associated with a premature stop to P-gp synthesis. In this study, we examined the full-length coding sequence of the ABCB1 gene in an ivermectin-sensitive Border Collie that lacked the aforementioned deletion mutation. The sequence was compared to the corresponding sequences of a wild-type Beagle and seven ivermectin-tolerant family members of the Border Collie. When compared to the wild-type Beagle sequence, that of the ivermectin-sensitive Border Collie was found to have one insertion mutation and eight single nucleotide polymorphisms (SNPs) in the coding sequence of the ABCB1 gene. While the eight SNPs were also found in the family members' sequences, the insertion mutation was found only in the ivermectin-sensitive dog. These results suggest the possibility that the SNPs are species-specific features of the ABCB1 gene in Border Collies, and that the insertion mutation may be related to ivermectin intolerance. PMID:21113104
Gehlot, Praveen; Singh, S K; Pathak, Rakesh
2012-09-01
Taxonomy of the fungus Pestalotiopsis based on morphological characters has been equivocal. Molecular characterization often Pestalotiopsis species was done based on nuclear ribosomal DNA internal transcribed spacer (ITS) amplifications. Results of the analyses showed that species of genus Pestalotiopsis are monophyletic. We report ITS length variations, single nucleotide polymorphisms (SNPs) and insertions/ deletions (INDELS) among ten species of Pestalotiopsis that did not cause any phylogenetic error at either genus or species designation levels. New gene sequences have been assigned (Gen Accession numbers from HM 190146 to HM 190155) by the National Centre for Biotechnology Information, USA.
2010-01-01
High-throughput genotype data can be used to identify genes important for local adaptation in wild populations, phenotypes in lab stocks, or disease-related traits in human medicine. Here we advance microarray-based genotyping for population genomics with Restriction Site Tiling Analysis. The approach simultaneously discovers polymorphisms and provides quantitative genotype data at 10,000s of loci. It is highly accurate and free from ascertainment bias. We apply the approach to uncover genomic differentiation in the purple sea urchin. PMID:20403197
Complex structure of knob DNA on maize chromosome 9. Retrotransposon invasion into heterochromatin.
Ananiev, E V; Phillips, R L; Rines, H W
1998-01-01
The recovery of maize (Zea mays L.) chromosome addition lines of oat (Avena sativa L.) from oat x maize crosses enables us to analyze the structure and composition of specific regions, such as knobs, of individual maize chromosomes. A DNA hybridization blot panel of eight individual maize chromosome addition lines revealed that 180-bp repeats found in knobs are present in each of these maize chromosomes, but the copy number varies from approximately 100 to 25, 000. Cosmid clones with knob DNA segments were isolated from a genomic library of an oat-maize chromosome 9 addition line with the help of the 180-bp knob-associated repeated DNA sequence used as a probe. Cloned knob DNA segments revealed a complex organization in which blocks of tandemly arranged 180-bp repeating units are interrupted by insertions of other repeated DNA sequences, mostly represented by individual full size copies of retrotransposable elements. There is an obvious preference for the integration of retrotransposable elements into certain sites (hot spots) of the 180-bp repeat. Sequence microheterogeneity including point mutations and duplications was found in copies of 180-bp repeats. The 180-bp repeats within an array all had the same polarity. Restriction maps constructed for 23 cloned knob DNA fragments revealed the positions of polymorphic sites and sites of integration of insertion elements. Discovery of the interspersion of retrotransposable elements among blocks of tandem repeats in maize and some other organisms suggests that this pattern may be basic to heterochromatin organization for eukaryotes. PMID:9691055
Kampf, Günter; Reise, Gesche; James, Claudia; Gittelbauer, Kirsten; Gosch, Jutta; Alpers, Birgit
2013-01-01
Peripheral venous catheters are frequently used in hospitalized patients but increase the risk of nosocomial bloodstream infection. Evidence-based guidelines describe specific steps that are known to reduce infection risk. However, the degree of guideline implementation in clinical practice is not known. The aim of this study was to determine the use of specific steps for insertion of peripheral venous catheters in clinical practice and to implement a multimodal intervention aimed at improving both compliance and the optimum order of the steps. The study was conducted at University Hospital Hamburg. An optimum procedure for inserting a peripheral venous catheter was defined based on three evidence-based guidelines (WHO, CDC, RKI) including five steps with 1A or 1B level of evidence: hand disinfection before patient contact, skin antisepsis of the puncture site, no palpation of treated puncture site, hand disinfection before aseptic procedure, and sterile dressing on the puncture site. A research nurse observed and recorded procedures for peripheral venous catheter insertion for healthcare workers in four different departments (endoscopy, central emergency admissions, pediatrics, and dermatology). A multimodal intervention with 5 elements was established (teaching session, dummy training, e-learning tool, tablet and poster, and direct feedback), followed by a second observation period. During the last observation week, participants evaluated the intervention. In the control period, 207 insertions were observed, and 202 in the intervention period. Compliance improved significantly for four of five steps (e.g., from 11.6% to 57.9% for hand disinfection before patient contact; p<0.001, chi-square test). Compliance with skin antisepsis of the puncture site was high before and after intervention (99.5% before and 99.0% after). Performance of specific steps in the correct order also improved (e.g., from 7.7% to 68.6% when three of five steps were done; p<0.001). The intervention was described as helpful by 46.8% of the participants, as neutral by 46.8%, and as disruptive by 6.4%. A multimodal strategy to improve both compliance with safety steps for peripheral venous catheter insertion and performance of an optimum procedure was effective and was regarded helpful by healthcare workers.
Pedra, Joao H F; Brandt, Amanda; Li, Hong-Mei; Westerman, Rick; Romero-Severson, Jeanne; Pollack, Richard J; Murdock, Larry L; Pittendrigh, Barry R
2003-11-01
Genomics information relating to human body lice is surprisingly scarce, and this has constrained studies of their physiology, immunology and vector biology. To identify novel body louse genes, we used engorged adult lice to generate a cDNA library. Initially, 1152 clones were screened for inserts, edited for removal of vector sequences and base pairs of poor quality, and viewed for splicing variations, gene families and polymorphism. Computational methods identified 506 inferred open reading frames including the first predicted louse defensin. The inferred defensin aligns well with other insect defensins and has highly conserved cysteine residues, as are known for other defensin sequences. Two cysteine and five serine proteinases were categorized according to their inferred catalytic sites. We also discovered seven putative ubiquitin-pathway genes and four iron metabolizing deduced enzymes. Finally, glutathione-S-transferases and cytochrome P450 genes were among the detoxification enzymes found. Results from this first systematic effort to discover human body louse genes should promote further studies in Phthiraptera and lice.
Phase stabilisation of hexagonal barium titanate doped with transition metals: A computational study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dawson, J.A., E-mail: mtp09jd@sheffield.ac.uk; Freeman, C.L.; Harding, J.H.
Interatomic potentials recently developed for the modelling of BaTiO{sub 3} have been used to explore the stabilisation of the hexagonal polymorph of BaTiO{sub 3} by doping with transition metals (namely Mn, Co, Fe and Ni) at the Ti-site. Classical simulations have been completed on both the cubic and hexagonal polymorphs to investigate the energetic consequences of transition metal doping on each polymorph. Ti-site charge compensation mechanisms have been used for the multi-valent transition metal ions and cluster binding energies have been considered. Simulations show a significant energetic gain when doping occurs at Ti sites in the face sharing dimers (Ti{submore » 2} sites) of the hexagonal polymorph compared with the doping of the cubic polymorph. This energetic difference between the two polymorphs is true for all transition metals tested and all charge states and in the case of tri- and tetra-valent dopants negative solution energies are found for the hexagonal polymorph suggesting actual polymorph stabilisation occurs with the incorporation of these ions as observed experimentally. Oxidation during incorporation of Ni{sup 2+} and Fe{sup 3+} ions has also been considered. - Graphical abstract: The representation of the strongest binding energy clusters for tri-valent dopants—(a) Ti{sub 2}/O{sub 1} cluster and (b) Ti{sub 2}/O{sub 2} cluster. Highlights: ► Classical simulations show a significant energetic gain when doping occurs at Ti sites in the face sharing dimers (Ti2 sites) of the hexagonal polymorph compared with the doping of the cubic polymorph. ► This energetic difference between the two polymorphs is true for all transition metals tested and all charge states. ► In the case of tri- and tetra- valent dopants negative solution energies are found for the hexagonal polymorph suggesting actual polymorph stabilisation occurs with the incorporation of these ions.« less
USDA-ARS?s Scientific Manuscript database
Until now, functional analyses of soybean genes have been very arduous because of the lack of a rapid transformation procedure. Recently identified the active endogenous type II transposable element, Tgm9, excises from insertion sites and restores wild-type phenotypes. Thus, this element provides a ...
Rosse, Izinara da Cruz; Steinberg, Raphael da Silva; Coimbra, Roney Santos; Peixoto, Maria Gabriela Campolina Diniz; Verneque, Rui Silva; Machado, Marco Antonio; Fonseca, Cleusa Graça; Carvalho, Maria Raquel Santos
2014-07-01
Diacylglycerol-O-acyltransferase (DGAT1) gene encodes the rate-limiting enzyme of triglyceride synthesis. A polymorphism in this gene, DGAT1 K232A, has been associated with milk production and composition in taurine breeds. However, this polymorphism is not a good tool for ascertaining the effects of this QTL in Bos indicus (Zebu), since the frequency of the DGAT1 232A allele is too low in these breeds. We sequenced the 3'-untranslated region of DGAT1 gene in a sample of bulls of the breeds Guzerá (Bos indicus) and Holstein (Bos taurus) and, using in silico analysis, we searched for genetic variation, evolutionary conservation, regulatory elements, and possible substitution effects. Six single nucleotide (SNPs) and one insertion-deletion (INDEL) polymorphisms were found in the Guzerá bulls. Additionally, we developed a preliminary association study, using this INDEL polymorphism as a genetic marker. A significant association was detected (P ≤ 0.05) between the INDEL (DGAT1 3'UTR INDEL) and the breeding values (BV) for protein, fat, and milk yields over a 305-day lactation period. The DGAT1 3' UTR INDEL genotype I/I (I, for insertion) was associated with lower BVs (-38.77 kg for milk, -1.86 kg for fat, and -1.48 kg for protein yields), when compared to the genotype I/D (D, for deletion). I/D genotype was lower D/D genotype (-34.98 kg milk, -1.73 kg fat, and -1.09 kg protein yields). This study reports the first polymorphism of DGAT1 3'UTR in the Guzerá breed, as well as its association with BV for milk protein, fat, and milk yields.
Jiang, Shuang; Zong, Yu; Yue, Xiaoyan; Postman, Joseph; Teng, Yuanwen; Cai, Danying
2015-02-01
Interspecific hybridization has been considered the major mode of evolution in Pyrus (pear), and thus, the genetic relationships within this genus have not been well documented. Retrotransposons are ubiquitous components of plant genomes and 42.4 % of the pear genome was reported to be long terminal repeat (LTR) retrotransposons, implying that retrotransposons might be significant in the evolution of Pyrus. In this study, 1,836 putative full-length LTR retrotransposons were isolated and 196 retrotransposon-based insertion polymorphism (RBIP) primers were developed, of which 24 pairs to the Ppcr1 subfamily of copia retrotransposons were used to analyze genetic diversity among 110 Pyrus accessions from Eurasia. Our results showed that Ppcr1 replicated many times in the development of cultivated Asian pears. The genetic structure analysis and the unweighted pair group method with arithmetic mean (UPGMA) dendrogram indicated that all accessions could be divided into Oriental and Occidental groups. In Oriental pears, wild pea pears clustered separately into independent groups in accordance with their morphological classifications. Cultivars of P. ussuriensis Maxim, P. pyrifolia Nakai, and P. pyrifolia Chinese white pear were mingled together, which inferred that hybridization events occurred during the development of the cultivated Asian pears. In Occidental pears, two clades were obtained in the UPGMA dendrogram in accordance with their geographical distribution; one contained the European species and the other included species from North Africa and West Asia. New findings in this study will be important to further understand the phylogeny of Pyrus and origins of cultivated pears.
Effects of the adenovirus 2 late promoter on simian virus 40 transcription and replication.
Grass, D S; Manley, J L
1986-01-01
A 100-base-pair fragment of adenovirus 2 (Ad2) DNA encompassing the major late transcriptional promoter was inserted into the simian virus 40 (SV40) late promoter region at SV40 nucleotide 294 to study the effects of a strong TATA box-containing promoter on SV40 late transcription. pSVAdE contains the insert in an orientation such that it would promote transcription towards the origin and early region of SV40, while the insert is in the opposite orientation in pSVAdL. Nuclease S1 analysis with 5'-end-labeled probes showed that in cells transfected with pSVAdE, the late mRNA initiation sites are essentially the same as in wild type, demonstrating that an insert of 100 base pairs can have no effect on utilization of the SV40 late start sites. In pSVAdL-transfected cells, however, the major late viral initiation site is now in the insert at +1 with respect to the Ad2 major late cap site. However, all of the SV40 initiation sites are still utilized and with the same efficiency relative to each other as in wild type. Thus, it appears that the Ad2 late promoter and the SV40 late promoter can function independently on the same DNA molecule, even when one promoter is embedded within the other. By using cytosine arabinoside to block DNA replication and thereby inhibit the onset of late expression, it has been shown that both the Ad2 late promoter and the SV40 late promoter have similar requirement for DNA replication in this context. In addition, pSVAdL showed dramatically diminished virus viability and VPI expression compared with both wildtype and pSVAdE. Possible explanations for this unexpected finding are discussed. Images PMID:3001338
Serotonin transporter gene polymorphisms and hyperserotonemia in autistic disorder.
Betancur, C; Corbex, M; Spielewoy, C; Philippe, A; Laplanche, J L; Launay, J M; Gillberg, C; Mouren-Siméoni, M C; Hamon, M; Giros, B; Nosten-Bertrand, M; Leboyer, M
2002-01-01
Previous studies have provided conflicting evidence regarding the association of the serotonin transporter (5-HTT) gene with autism. Two polymorphisms have been identified in the human 5-HTT gene, a VNTR in intron 2 and a functional deletion/insertion in the promoter region (5-HTTLPR) with short and long variants. Positive associations of the 5-HTTLPR polymorphism with autism have been reported by two family-based studies, but one found preferential transmission of the short allele and the other of the long allele. Two subsequent studies failed to find evidence of transmission disequilibrium at the 5-HTTLPR locus. These conflicting results could be due to heterogeneity of clinical samples with regard to serotonin (5-HT) blood levels, which have been found to be elevated in some autistic subjects. Thus, we examined the association of the 5-HTTLPR and VNTR polymorphisms of the 5-HTT gene with autism, and we investigated the relationship between 5-HTT variants and whole-blood 5-HT. The transmission/disequilibrium test (TDT) revealed no linkage disequilibrium at either loci in a sample of 96 families comprising 43 trios and 53 sib pairs. Furthermore, no significant relationship between 5-HT blood levels and 5-HTT gene polymorphisms was found. Our results suggest that the 5-HTT gene is unlikely to play a major role as a susceptibility factor in autism.
Serotonin transporter gene polymorphisms and hyperserotonemia in autistic disorder
Betancur, Catalina; Corbex, Marylis; Spielewoy, Cécile; Philippe, Anne; Laplanche, Jean-Louis; Launay, Jean-Marie; Gillberg, Christopher; Mouren-Simeoni, Marie-Christine; Hamon, Michel; Giros, Bruno; Nosten-Bertrand, Marika; Leboyer, Marion
2002-01-01
Previous studies have provided conflicting evidence regarding the association of the serotonin transporter (5-HTT) gene with autism. Two polymorphisms have been identified in the human 5-HTT gene, a VNTR in intron 21 and a functional deletion/insertion in the promoter region (5-HTTLPR) with short and long variants.2 Positive associations of the 5-HTTLPR polymorphism with autism have been reported by two family-based studies, but one found preferential transmission of the short allele3 and the other of the long allele.4 Two subsequent studies failed to find evidence of transmission disequilibrium at the 5-HTTLPR locus.5,6 These conflicting results could be due to heterogeneity of clinical samples with regard to serotonin (5-HT) blood levels, which have been found to be elevated in some autistic subjects.7–9 Thus, we examined the association of the 5-HTTLPR and VNTR polymorphisms of the 5-HTT gene with autism, and we investigated the relationship between 5-HTT variants and whole-blood 5-HT. The transmission/disequilibrium test (TDT) revealed no linkage disequilibrium at either loci in a sample of 96 families comprising 43 trios and 53 sib pairs. Furthermore, no significant relationship between 5-HT blood levels and 5-HTT gene polymorphisms was found. Our results suggest that the 5-HTT gene is unlikely to play a major role as a susceptibility factor in autism. PMID:11803447
Wang, Yuying; Peng, Wen; Zhang, Xiaoxue; Qiao, Huibo; Wang, Li; Xu, Zhigang; Wu, Chenguang
2016-07-01
To investigate the associations between the insertion/deletion (I/D) polymorphisms in the angiotensin converting enzyme (ACE) gene and susceptibility to diabetic kidney disease (DKD); and the efficacy of valsartan in reducing the urine protein in Type 2 diabetes mellitus (T2DM) patients. We enrolled 128 T2DM patients in this study, including 54 cases with DKD (DKD+) and 74 controls (DKD-). The ACE polymorphism was assayed by polymerase chain reaction (PCR), and the genotype distribution and allele frequency were analyzed. The DKD+ group was subdivided into the DD, ID and II subgroups, based on their genotypes. In addition, patients with DKD received valsartan treatment for 12 weeks. We determined changes in the urinary albumin to creatinine ratio (ACR) and serum creatinine (SCr). The frequencies of the genotypes DD and ID were higher in the DKD+ than in the DKD- group. The frequency of allele D was higher, and of allele I was lower, in the DKD+ than in DKD- group (p < 0.05). Following valsartan treatment, albuminuria was significantly decreased in subgroups DD and ID (p < 0.05). In T2DM patients, the ACE I/D polymorphism was associated with onset of DKD. Furthermore, the ACE I/D polymorphism influenced the renoprotective response to valsartan: Patients with the DD genotype benefitted the most from this treatment. © The Author(s) 2016.
Choi, Jung Ju; Kim, Ji Young; Lee, Dongchul; Chang, Young Jin; Cho, Noo Ree; Kwak, Hyun Jeong
2016-03-22
The pharmacokinetics and pharmacodynamics of an anesthetic drug may be influenced by gender. The purpose of this study was to compare effect-site half maximal effective concentrations (EC50) of propofol in male and female patients during i-gel insertion with dexmedetomidine 0.5 μg/kg without muscle relaxants. Forty patients, aged 20-46 years of ASA physical status I or II, were allocated to one of two groups by gender (20 patients per group). After the infusion of dexmedetomidine 0.5 μg/kg over 2 min, anesthesia was induced with a pre-determined effect-site concentration of propofol by target controlled infusion. Effect-site EC50 values of propofol for successful i-gel insertion were determined using the modified Dixon's up-and-down method. Mean effect-site EC50 ± SD of propofol for successful i-gel insertion was significantly higher for men than women (5.46 ± 0.26 μg/ml vs. 3.82 ± 0.34 μg/ml, p < 0.01). The EC50 of propofol in men was approximately 40% higher than in women. Using isotonic regression with a bootstrapping approach, the estimated EC50 (95% confidence interval) of propofol was also higher in men [5.32 (4.45-6.20) μg/ml vs. 3.75 (3.05-4.43) μg/ml]. The estimated EC95 (95% confidence interval) of propofol in men and women were 5.93 (4.72-6.88) μg/ml and 4.52 (3.02-5.70) μg/ml, respectively. During i-gel insertion with dexmedetomidine 0.5 μg/kg without muscle relaxant, male patients had higher effect-site EC50 for propofol using Schnider's model. Based on the results of this study, patient gender should be considered when determining the optimal dose of propofol during supraglottic airway insertion. ClinicalTrials.gov identifier: NCT02268656. Registered August 26, 2014.
Infraspecific DNA methylation polymorphism in cotton (Gossypium hirsutum L.).
Keyte, Anna L; Percifield, Ryan; Liu, Bao; Wendel, Jonathan F
2006-01-01
Cytosine methylation is important in the epigenetic regulation of gene expression and development in plants and has been implicated in silencing duplicate genes after polyploid formation in several plant groups. Relatively little information exists, however, on levels and patterns of methylation polymorphism (MP) at homologous loci within species. Here we explored the levels and patterns of methylation-polymorphism diversity at CCGG sites within allotetraploid cotton, Gossypium hirsutum, using a methylation-sensitive amplified fragment length polymorphism screen and a selected set of 20 G. hirsutum accessions for which we have information on genetic polymorphism levels and relationships. Methylation and MP exist at high levels within G. hirsutum: of 150 HpaII/MspI sites surveyed, 48 were methylated at the inner cytosine (32%) and 32 of these were polymorphic (67%). Both these values are higher than comparable measures of genetic diversity using restriction fragment length polymorphisms. The high percentage of methylation-polymorphic sites and potential relationship to gene expression underscore the potential significance of MP within and among populations. We speculate that biased correlation of methylation-polymorphic sites and genes in cotton may be a consequence of polyploidy and the attendant doubling of all genes.
Polymorphism at codon 36 of the p53 gene.
Felix, C A; Brown, D L; Mitsudomi, T; Ikagaki, N; Wong, A; Wasserman, R; Womer, R B; Biegel, J A
1994-01-01
A polymorphism at codon 36 in exon 4 of the p53 gene was identified by single strand conformation polymorphism (SSCP) analysis and direct sequencing of genomic DNA PCR products. The polymorphic allele, present in the heterozygous state in genomic DNAs of four of 100 individuals (4%), changes the codon 36 CCG to CCA, eliminates a FinI restriction site and creates a BccI site. Including this polymorphism there are four known polymorphisms in the p53 coding sequence.
Comparison of Insertional RNA Editing in Myxomycetes
Chen, Cai; Frankhouser, David; Bundschuh, Ralf
2012-01-01
RNA editing describes the process in which individual or short stretches of nucleotides in a messenger or structural RNA are inserted, deleted, or substituted. A high level of RNA editing has been observed in the mitochondrial genome of Physarum polycephalum. The most frequent editing type in Physarum is the insertion of individual Cs. RNA editing is extremely accurate in Physarum; however, little is known about its mechanism. Here, we demonstrate how analyzing two organisms from the Myxomycetes, namely Physarum polycephalum and Didymium iridis, allows us to test hypotheses about the editing mechanism that can not be tested from a single organism alone. First, we show that using the recently determined full transcriptome information of Physarum dramatically improves the accuracy of computational editing site prediction in Didymium. We use this approach to predict genes in the mitochondrial genome of Didymium and identify six new edited genes as well as one new gene that appears unedited. Next we investigate sequence conservation in the vicinity of editing sites between the two organisms in order to identify sites that harbor the information for the location of editing sites based on increased conservation. Our results imply that the information contained within only nine or ten nucleotides on either side of the editing site (a distance previously suggested through experiments) is not enough to locate the editing sites. Finally, we show that the codon position bias in C insertional RNA editing of these two organisms is correlated with the selection pressure on the respective genes thereby directly testing an evolutionary theory on the origin of this codon bias. Beyond revealing interesting properties of insertional RNA editing in Myxomycetes, our work suggests possible approaches to be used when finding sequence motifs for any biological process fails. PMID:22383871
HIV genetic information and clonal growth
Based on an analysis of blood cells from five HIV-infected individuals, NCI researchers have identified more than 2,400 HIV DNA insertion sites. Analysis of these sites showed that there is extensive clonal expansion (growth) of HIV infected cells.
A Novel Locomotion-based Validation Assay for Candidate Drugs Using Drosophila DYT1 Disease Model
2014-06-01
rescue the locomotion defects of Drosophila larvae caused by the expression of human torsinAΔE. These results demonstrated that human torsinA can... Drosophila dtorsin∆D transgenic lines dtorsin∆E and dtorsin∆D cDNA constructs were made from the wild type dtorsin cDNA using QuikChange II XL Site...After confirming mutated sequences , the insert was again cut out with EcoRI and NotI and inserted between EcoRI and NotI sites of pUAST [2] to produce
Hamada, Taku; Kotani, Kazuhiko; Nagai, Narumi; Tsuzaki, Kokoro; Sano, Yoshiko; Matsuoka, Yukiyo; Fujibayashi, Mami; Kiyohara, Natsuki; Tanaka, Seitaro; Yoshimura, Makiko; Egawa, Kahori; Kitagawa, Yoshinori; Kiso, Yoshinobu; Moritani, Toshio; Sakane, Naoki
2011-01-01
Genetic polymorphisms of the renin-angiotensin system have been implicated in cardiovascular and metabolic diseases. The purpose of this study was to investigate whether the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene and 3123C/A polymorphism of the angiotensin II type 2 receptor (AT(2)R) gene affect blood pressure and other obesity-related metabolic changes in response to low-energy diets using meal replacement shakes for weight loss. Clinical, metabolic, and biochemical profiles were measured before and after a 2-mo intervention in 32 obese women (age 49.9 ± 8.4 [SD] y; BMI 28.4 ± 3.3 kg/m²) restricted to 1200 kcal/d (5021 kJ/d). The polymorphisms were determined with an intercalater-mediated FRET probe assay system. Although weight loss and nutrient intake levels did not differ among the genotypes, the reduction in body fat after weight loss was significantly less in the ACE deletion/deletion (D/D) genotype than insertion/insertion (I/I) plus I/D genotype (-2.25 ± 1.40% versus -0.80 ± 1.57%, P < 0.05). The AT₂R A/A group had significantly less improved levels of systolic blood pressure (-7.23 ± 8.50 versus 2.50 ± 12.6 mmHg, P < 0.05), low-density lipoprotein-cholesterol (-0.36 ± 0.29 versus -0.09 ± 0.25 mmol/L, P < 0.05), carbohydrate (-54.4 ± 27.2 versus -31.8 ± 16.3 mg/min, P < 0.05) and fat oxidation (8.31 ± 11.86 versus 0.05 ± 9.99 mg/min, P < 0.05) than the C/C plus C/A genotypes. The present findings suggest that the homozygous form of the ACE gene may hinder the improvement of body fat and that the homozygous form of the AT₂R gene may make improving systolic blood pressure and some obesity-related metabolic parameters through a dietary intervention difficult among obese women. Copyright © 2011 Elsevier Inc. All rights reserved.
Whole genome re-sequencing of date palms yields insights into diversification of a fruit tree crop.
Hazzouri, Khaled M; Flowers, Jonathan M; Visser, Hendrik J; Khierallah, Hussam S M; Rosas, Ulises; Pham, Gina M; Meyer, Rachel S; Johansen, Caryn K; Fresquez, Zoë A; Masmoudi, Khaled; Haider, Nadia; El Kadri, Nabila; Idaghdour, Youssef; Malek, Joel A; Thirkhill, Deborah; Markhand, Ghulam S; Krueger, Robert R; Zaid, Abdelouahhab; Purugganan, Michael D
2015-11-09
Date palms (Phoenix dactylifera) are the most significant perennial crop in arid regions of the Middle East and North Africa. Here, we present a comprehensive catalogue of approximately seven million single nucleotide polymorphisms in date palms based on whole genome re-sequencing of a collection of 62 cultivars. Population structure analysis indicates a major genetic divide between North Africa and the Middle East/South Asian date palms, with evidence of admixture in cultivars from Egypt and Sudan. Genome-wide scans for selection suggest at least 56 genomic regions associated with selective sweeps that may underlie geographic adaptation. We report candidate mutations for trait variation, including nonsense polymorphisms and presence/absence variation in gene content in pathways for key agronomic traits. We also identify a copia-like retrotransposon insertion polymorphism in the R2R3 myb-like orthologue of the oil palm virescens gene associated with fruit colour variation. This analysis documents patterns of post-domestication diversification and provides a genomic resource for this economically important perennial tree crop.
Whole genome re-sequencing of date palms yields insights into diversification of a fruit tree crop
Hazzouri, Khaled M.; Flowers, Jonathan M.; Visser, Hendrik J.; Khierallah, Hussam S. M.; Rosas, Ulises; Pham, Gina M.; Meyer, Rachel S.; Johansen, Caryn K.; Fresquez, Zoë A.; Masmoudi, Khaled; Haider, Nadia; El Kadri, Nabila; Idaghdour, Youssef; Malek, Joel A.; Thirkhill, Deborah; Markhand, Ghulam S.; Krueger, Robert R.; Zaid, Abdelouahhab; Purugganan, Michael D.
2015-01-01
Date palms (Phoenix dactylifera) are the most significant perennial crop in arid regions of the Middle East and North Africa. Here, we present a comprehensive catalogue of approximately seven million single nucleotide polymorphisms in date palms based on whole genome re-sequencing of a collection of 62 cultivars. Population structure analysis indicates a major genetic divide between North Africa and the Middle East/South Asian date palms, with evidence of admixture in cultivars from Egypt and Sudan. Genome-wide scans for selection suggest at least 56 genomic regions associated with selective sweeps that may underlie geographic adaptation. We report candidate mutations for trait variation, including nonsense polymorphisms and presence/absence variation in gene content in pathways for key agronomic traits. We also identify a copia-like retrotransposon insertion polymorphism in the R2R3 myb-like orthologue of the oil palm virescens gene associated with fruit colour variation. This analysis documents patterns of post-domestication diversification and provides a genomic resource for this economically important perennial tree crop. PMID:26549859
A universal method for automated gene mapping
Zipperlen, Peder; Nairz, Knud; Rimann, Ivo; Basler, Konrad; Hafen, Ernst; Hengartner, Michael; Hajnal, Alex
2005-01-01
Small insertions or deletions (InDels) constitute a ubiquituous class of sequence polymorphisms found in eukaryotic genomes. Here, we present an automated high-throughput genotyping method that relies on the detection of fragment-length polymorphisms (FLPs) caused by InDels. The protocol utilizes standard sequencers and genotyping software. We have established genome-wide FLP maps for both Caenorhabditis elegans and Drosophila melanogaster that facilitate genetic mapping with a minimum of manual input and at comparatively low cost. PMID:15693948
Hubácek, J A; Pistulková, H; Skodová, Z; Lánská, V; Poledne, R
2004-01-01
High plasma lipids are one of the risk factor of atherosclerosis. Both environmental (diet, physic activity) and genetic factors have been implicated in the development of hyperlipidaemia. Apolipoprotein (apo) CI plays an important role in plasma cholesterol and triglycerides transport by VLDL particles. The aim of the study was to establish the role of the insertion/deletion polymorphism in apoCI gene in the determination of plasma lipids in children. Using PCR and restriction analysis (HpaI) we have measured I/D polymorphism in APOCI gene in two groups of children selected from opposite ends of the cholesterol distribution curve of 2000 children. Eighty-two children in high-(HCG) and eighty-six children in low-(LCG) cholesterolemic groups participated on the study. No significant difference was found in the frequencies of the APOCI genotypes or alleles between HCG vs. LCG. Association between LDL cholesterol and genotypes within the LCG was found--the D/D homozygotes have higher lipid level compared to the others (p < 0.05). In LCG opposite, but insignificant (p = 0.09) trend was observed. The widespread I/D polymorphism in the gene for APOCI determines the plasma lipid levels in childhood and it could become another important genetic marker that plays a role in the genetic determination of cholesterolemia.
Jalil, Jorge E; Córdova, Samuel; Ocaranza, Marí a; Schumacher, Erwin; Braun, Sandra; Chamorro, Gastón; Fardella, Carlos; Lavandero, Sergio
2002-08-01
The insertion/deletion ACE polymorphism (ACE I/D) regulates different levels of circulating and tissue ACE activities, which may induce diverse adrenergic responses to physiological stimuli. The aim of this study was to evaluate the influence of the ACE I/D polymorphism on the adrenergic response to isotonic exercise in middle-aged hypertensive patients. Submaximal exercise (on a treadmill, using the Naughton protocol at 75% of maximal heart rate) was performed in 34 patients homozygous for the ACE I/D polymorphism (ACE II and ACE DD) with untreated essential hypertension (II = 19, DD = 15). Plasma venous adrenaline and noradrenaline were measured at rest and at submaximal exercise. Plasma ACE activity was significantly higher in the hypertensive patients carrying the ACE DD genotype compared with the ACE II group. Left atrium size, as well as LV dimensions, mass, and function, were similar in both groups. Total exercise time, baseline and 75% maximal heart rate (MHR) and blood pressure were similar in both groups. Baseline plasma adrenaline and noradrenaline levels were similar in both groups and increased significantly (p<0.05) by ca. 300% at submaximal exercise without differences between groups. The presence of the D allele on the ACE gene in middle-aged hypertensive patients determines higher circulating ACE activity but not increased sympathetic activity in response to submaximal exercise.
Gene and enhancer trap tagging of vascular-expressed genes in poplar trees
Andrew Groover; Joseph R. Fontana; Gayle Dupper; Caiping Ma; Robert Martienssen; Steven Strauss; Richard Meilan
2004-01-01
We report a gene discovery system for poplar trees based on gene and enhancer traps. Gene and enhancer trap vectors carrying the β-glucuronidase (GUS) reporter gene were inserted into the poplar genome via Agrobacterium tumefaciens transformation, where they reveal the expression pattern of genes at or near the insertion sites. Because GUS...
Laukkanen, Jari A; Mäkikallio, Timo H; Kauhanen, Jussi; Kurl, Sudhir
2009-10-01
Adrenoceptors mediate contraction of vascular smooth muscle and induce coronary vasoconstriction in humans. A deletion variant of the human alpha(2B)-adrenoreseptor of glutamic acid residues has been associated with impaired receptor desensitization. This receptor variant could, therefore, be involved in cardiovascular diseases associated with enhanced vasoconstriction. Our aim was to study whether an insertion/deletion (I/D) polymorphism in the alpha(2B)-adrenoceptor gene is associated with the risk for sudden cardiac death. This was a prospective population-based study investigating risk factors for cardiovascular diseases in middle-aged men from 42 to 60 years from eastern Finland. The study is based on 1,606 men with complete data on DNA observed for an average time of 17 years. In this study population, 338 men (21%) had the D/D genotype, 467 (29%) had the I/I genotype, and 801 (50%) had a heterozygous genotype. There were 76 sudden cardiac deaths during follow-up (0.81 deaths/1,000 persons per year). In a Cox model adjusting for other coronary risk factors (age, systolic blood pressure, smoking, diabetes, serum low-density lipoprotein and high-density lipoprotein cholesterol, body mass index, and exercise-induced myocardial ischemia), men with the D/D or I/D genotype had 1.97 times (95% CI 1.08-3.59, P = .026) higher risk to experience sudden cardiac death (20 events for D/D genotype, 13 events for I/I genotype, and 43 events for I/D genotype) compared with men carrying the I/I genotype. In addition, the alpha(2B)-adrenoceptor D/D genotype was associated with the risk of coronary heart disease death and acute coronary events, after adjusting for risk factors. The genetic polymorphism of the alpha(2B)-adrenoreceptor is genetic risk predictor for sudden cardiac death.
Genetic Architectures of Quantitative Variation in RNA Editing Pathways
Gu, Tongjun; Gatti, Daniel M.; Srivastava, Anuj; Snyder, Elizabeth M.; Raghupathy, Narayanan; Simecek, Petr; Svenson, Karen L.; Dotu, Ivan; Chuang, Jeffrey H.; Keller, Mark P.; Attie, Alan D.; Braun, Robert E.; Churchill, Gary A.
2016-01-01
RNA editing refers to post-transcriptional processes that alter the base sequence of RNA. Recently, hundreds of new RNA editing targets have been reported. However, the mechanisms that determine the specificity and degree of editing are not well understood. We examined quantitative variation of site-specific editing in a genetically diverse multiparent population, Diversity Outbred mice, and mapped polymorphic loci that alter editing ratios globally for C-to-U editing and at specific sites for A-to-I editing. An allelic series in the C-to-U editing enzyme Apobec1 influences the editing efficiency of Apob and 58 additional C-to-U editing targets. We identified 49 A-to-I editing sites with polymorphisms in the edited transcript that alter editing efficiency. In contrast to the shared genetic control of C-to-U editing, most of the variable A-to-I editing sites were determined by local nucleotide polymorphisms in proximity to the editing site in the RNA secondary structure. Our results indicate that RNA editing is a quantitative trait subject to genetic variation and that evolutionary constraints have given rise to distinct genetic architectures in the two canonical types of RNA editing. PMID:26614740
Polymorphisms in the phosducin (PDC) gene on chromosome 1q25-32
DOE Office of Scientific and Technical Information (OSTI.GOV)
Humphries, P.; Mansergh, F.C.; Farrar, G.J.
1994-09-01
Phosducin (33 kDa protein or MEKA) is a principal water-soluble phosphoprotein in the rod and cone photoreceptor cells and pinealocytes. This protein modulates the phototransduction cascade by binding to the beta and gamma subunit complexes of transducin. The PDC gene has been mapped to 1q25-32, the region of linkage of two hereditary retinal degenerative disorders; autosomal dominant juvenile-onset open-angle glaucoma and one form of autosomal recessive RP. Using previously published sequence data, PCR primers were designed to amplify the coding and 5{prime} flanking regions of the PDC gene. Direct sequencing revealed three polymorphisms in the 5{prime} flanking region, two ofmore » which were in regions highly homologous between humans and mice. Analysis of the polymorphisms was then extended to larger population samples using SSCPE and denaturing gel analysis. The first polymorphism PDC1 resulted from an insertion of a G residue at position -653/4. Allele frequencies were determined to be 0.51 (insG) and 0.49 (normal) giving a PIC value of 0.50. A deletion of a T residue at position -488 was the basis of the PDC2 polymorphism with allele frequencies of 0.88 (normal) and 0.12 (delT) and a PIC value of 0.21. Interestingly, the allele with an inserted G residue in PDC1 always segregrated with the deleted T allele in PDC2. The third polymorphism PDC3 was caused by a T or G residue at position -1083. Allele frequencies of 0.26 (G residue) and 0.74 (T residue) were determined from an analysis of 80 individuals with an overall PIC value of 0.39. The identification of these three polymorphisms in the PDC gene will be useful for future genetic linkage studies of chromosome 1q in inherited retinopathies.« less
Validation of the high-throughput marker technology DArT using the model plant Arabidopsis thaliana.
Wittenberg, Alexander H J; van der Lee, Theo; Cayla, Cyril; Kilian, Andrzej; Visser, Richard G F; Schouten, Henk J
2005-08-01
Diversity Arrays Technology (DArT) is a microarray-based DNA marker technique for genome-wide discovery and genotyping of genetic variation. DArT allows simultaneous scoring of hundreds of restriction site based polymorphisms between genotypes and does not require DNA sequence information or site-specific oligonucleotides. This paper demonstrates the potential of DArT for genetic mapping by validating the quality and molecular basis of the markers, using the model plant Arabidopsis thaliana. Restriction fragments from a genomic representation of the ecotype Landsberg erecta (Ler) were amplified by PCR, individualized by cloning and spotted onto glass slides. The arrays were then hybridized with labeled genomic representations of the ecotypes Columbia (Col) and Ler and of individuals from an F(2) population obtained from a Col x Ler cross. The scoring of markers with specialized software was highly reproducible and 107 markers could unambiguously be ordered on a genetic linkage map. The marker order on the genetic linkage map coincided with the order on the DNA sequence map. Sequencing of the Ler markers and alignment with the available Col genome sequence confirmed that the polymorphism in DArT markers is largely a result of restriction site polymorphisms.
indCAPS: A tool for designing screening primers for CRISPR/Cas9 mutagenesis events.
Hodgens, Charles; Nimchuk, Zachary L; Kieber, Joseph J
2017-01-01
Genetic manipulation of organisms using CRISPR/Cas9 technology generally produces small insertions/deletions (indels) that can be difficult to detect. Here, we describe a technique to easily and rapidly identify such indels. Sequence-identified mutations that alter a restriction enzyme recognition site can be readily distinguished from wild-type alleles using a cleaved amplified polymorphic sequence (CAPS) technique. If a restriction site is created or altered by the mutation such that only one allele contains the restriction site, a polymerase chain reaction (PCR) followed by a restriction digest can be used to distinguish the two alleles. However, in the case of most CRISPR-induced alleles, no such restriction sites are present in the target sequences. In this case, a derived CAPS (dCAPS) approach can be used in which mismatches are purposefully introduced in the oligonucleotide primers to create a restriction site in one, but not both, of the amplified templates. Web-based tools exist to aid dCAPS primer design, but when supplied sequences that include indels, the current tools often fail to suggest appropriate primers. Here, we report the development of a Python-based, species-agnostic web tool, called indCAPS, suitable for the design of PCR primers used in dCAPS assays that is compatible with indels. This tool should have wide utility for screening editing events following CRISPR/Cas9 mutagenesis as well as for identifying specific editing events in a pool of CRISPR-mediated mutagenesis events. This tool was field-tested in a CRISPR mutagenesis experiment targeting a cytokinin receptor (AHK3) in Arabidopsis thaliana. The tool suggested primers that successfully distinguished between wild-type and edited alleles of a target locus and facilitated the isolation of two novel ahk3 null alleles. Users can access indCAPS and design PCR primers to employ dCAPS to identify CRISPR/Cas9 alleles at http://indcaps.kieber.cloudapps.unc.edu/.
2009-01-01
Background Expressed sequence tags (ESTs) are an important source of gene-based markers such as those based on insertion-deletions (Indels) or single-nucleotide polymorphisms (SNPs). Several gel based methods have been reported for the detection of sequence variants, however they have not been widely exploited in common bean, an important legume crop of the developing world. The objectives of this project were to develop and map EST based markers using analysis of single strand conformation polymorphisms (SSCPs), to create a transcript map for common bean and to compare synteny of the common bean map with sequenced chromosomes of other legumes. Results A set of 418 EST based amplicons were evaluated for parental polymorphisms using the SSCP technique and 26% of these presented a clear conformational or size polymorphism between Andean and Mesoamerican genotypes. The amplicon based markers were then used for genetic mapping with segregation analysis performed in the DOR364 × G19833 recombinant inbred line (RIL) population. A total of 118 new marker loci were placed into an integrated molecular map for common bean consisting of 288 markers. Of these, 218 were used for synteny analysis and 186 presented homology with segments of the soybean genome with an e-value lower than 7 × 10-12. The synteny analysis with soybean showed a mosaic pattern of syntenic blocks with most segments of any one common bean linkage group associated with two soybean chromosomes. The analysis with Medicago truncatula and Lotus japonicus presented fewer syntenic regions consistent with the more distant phylogenetic relationship between the galegoid and phaseoloid legumes. Conclusion The SSCP technique is a useful and inexpensive alternative to other SNP or Indel detection techniques for saturating the common bean genetic map with functional markers that may be useful in marker assisted selection. In addition, the genetic markers based on ESTs allowed the construction of a transcript map and given their high conservation between species allowed synteny comparisons to be made to sequenced genomes. This synteny analysis may support positional cloning of target genes in common bean through the use of genomic information from these other legumes. PMID:20030833
Area of the tibial insertion site of the anterior cruciate ligament as a predictor for graft size.
Guenther, Daniel; Irarrázaval, Sebastian; Albers, Marcio; Vernacchia, Cara; Irrgang, James J; Musahl, Volker; Fu, Freddie H
2017-05-01
To determine the distribution of different sizes of the area of the tibial insertion site among the population and to evaluate whether preoperative MRI measurements correlate with intraoperative findings to enable preoperative planning of the required graft size to cover the tibial insertion site sufficiently. The hypothesis was that the area of the tibial insertion site varies among individuals and that there is good agreement between MRI and intraoperative measurements. Intraoperative measurements of the tibial insertion site were taken on 117 patients. Three measurements were taken in each plane building a grid to cover the tibial insertion site as closely as possible. The mean of the three measurements in each plane was used for determination of the area. Two orthopaedic surgeons, who were blinded to the intraoperative measurements, took magnetic resonance imaging (MRI) measurements of the area of the tibial insertion site at two different time points. The intraoperative measured mean area was 123.8 ± 21.5 mm 2 . The mean area was 132.8 ± 15.7 mm 2 (rater 1) and 136.7 ± 15.4 mm 2 (rater 2) when determined using MRI. The size of the area was approximately normally distributed. Inter-rater (0.89; 95 % CI 0.84, 0.92; p < 0.001) and intrarater reliability (rater 1: 0.97; 95 % CI 0.95, 0.98; p < 0.001; rater 2: 0.95; 95 % CI 0.92, 0.96; p < 0.001) demonstrated excellent test-retest reliability. There was good agreement between MRI and intraoperative measurement of tibial insertion site area (ICCs rater 1: 0.80; 95 % CI 0.71, 0.87; p < 0.001; rater 2: 0.87; 95 % CI 0.81, 0.91; p < 0.001). The tibial insertion site varies in size and shape. Preoperative determination of the area using MRI is repeatable and enables planning of graft choice and size to optimally cover the tibial insertion site. III.
Fu, Wen; Zhuo, Zhen-Jian; Chen, Yung-Chang; Zhu, Jinhong; Zhao, Zhang; Jia, Wei; Hu, Jin-Hua; Fu, Kai; Zhu, Shi-Bo; He, Jing; Liu, Guo-Chang
2017-02-07
Nuclear factor-kappa B1 (NF-κB1) is a pleiotropic transcription factor and key contributor to tumorigenesis in many types of cancer. Numerous studies have addressed the association of a functional insertion (I)/deletion (D) polymorphism (-94ins/delATTG, rs28362491) in the promoter region of NFKB1 gene with the risk of various types of cancer; however, their conclusions have been inconsistent. We therefore conducted a meta-analysis to reevaluate this association. PubMed, EMBASE, China National Knowledge infrastructure (CNKI), and WANFANG databases were searched through July 2016 to retrieve relevant studies. After careful assessment, 50 case-control studies, comprising 18,299 cases and 23,484 controls were selected. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were used to determine the strength of the association. The NFKB1 -94ins/delATTG polymorphism was associated with a decreased risk of overall cancer in the homozygote model (DD vs. II): OR = 0.75, 95% CI = 0.64-0.87); heterozygote model (ID vs. II): OR = 0.91, 95% CI = 0.83-0.99; recessive model (DD vs. ID/II): OR = 0.81, 95% CI = 0.71-0.91; dominant model (ID/DD vs. II): OR = 0.86, 95% CI = 0.78-0.95; and allele contrast model (D vs. I): OR = 0.88, 95% CI = 0.81-0.95). Subgroup and stratified analyses revealed decreased risks for lung cancer, nasopharyngeal carcinoma, prostate cancer, ovarian cancer, and oral squamous cell carcinoma, and this association held true also for Asians (especially Chinese subjects) in hospital-based studies, and in studies with quality scores less than nine. Well-designed, large-scale case-control studies are needed to confirm these results.
Maca-Meyer, N; Villar, J; Pérez-Méndez, L; Cabrera de León, A; Flores, C
2004-11-01
Classical, mitochondrial DNA (mtDNA) and Y chromosome markers have been used to examine the genetic admixture in present day inhabitants of the Canary Islands. In this study, we report the analysis of ten autosomal Alu insertion polymorphisms in 364 samples from the seven main islands of the Archipelago, and their comparison to continental samples. The detection of population-specific alleles from the Iberian Peninsula and Northwest Africa, as well as their affinities on the basis of genetic distances and principal component analysis, support a clear link between these populations. Coincident with previous results, the Canarian gene pool can be distinguished as being halfway between those of its putative parents, although with a major Iberian contribution (62-78%). Both the substantial Northwest African contribution (23-38%), and the minor sub-Saharan African input (3%), suggest that the genetic legacy from the aborigines and slaves still persists in the Canary Islanders.
Ferreira Palha, Teresinha de Jesus Brabo; Ribeiro Rodrigues, Elzemar Martins; Cavalcante, Giovanna Chaves; Marrero, Andrea; de Souza, Ilíada Rainha; Seki Uehara, Clineu Julien; Silveira da Motta, Carlos Henrique Ares; Koshikene, Daniela; da Silva, Dayse Aparecida; de Carvalho, Elizeu Fagundes; Chemale, Gustavo; Freitas, Jorge M; Alexandre, Lídia; Paranaiba, Renato T F; Soler, Mirella Perruccio; Santos, Sidney
2015-11-01
The aim of this study was to estimate the diversity of 30 insertion/deletion (INDEL) markers (Investigator(®) DIPplex kit) in a sample of 519 individuals from six Brazilian states and to evaluate their applicability in forensic genetics. All INDEL markers were found to be highly polymorphic in the Brazilian population and were in Hardy-Weinberg equilibrium. To determine their forensic suitability in the Brazilian population, the markers were evaluated for discrimination power, match probability and exclusion power. The combined discrimination power (CDP), combined match power (CMP) and combined power of exclusion (CPE) were higher than 0.999999, 3.4 × 10(-13) and 0.9973, respectively. Further comparison of 29 worldwide populations revealed significant genetic differences between continental populations and a closer relationship between the Brazilian and European populations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Prevention of Device-Related Healthcare-Associated Infections
Septimus, Edward J.; Moody, Julia
2016-01-01
Healthcare-associated infections (HAIs) are a leading cause of morbidity and mortality in hospitalized patients. Up to 15% of patients develop an infection while hospitalized in the United States, which accounts for approximately 1.7 million HAIs, 99,000 deaths annually and over 10 billion dollars in costs per year. A significant percentage of HAIs are preventable using evidenced-based strategies. In terms of device-related HAIs it is estimated that 65-70% of catheter-line associated bloodstream infections (CLABSIs) and catheter-associated urinary tract infections (CAUTIs) are preventable. To prevent CLABSIs a bundle which includes hand hygiene prior to insertion and catheter manipulation, use of chlorhexidene alcohol for site preparation and maintenance, use of maximum barrier for catheter insertion, site selection, removing nonessential lines, disinfect catheter hubs before assessing line, and dressing changes are essential elements of basic practices. To prevent CAUTIs a bundle that includes hand hygiene for insertion and catheter or bag manipulation, inserting catheters for appropriate indications, insert using aseptic technique, remove catheters when no longer needed, maintain a close system keeping bag and tubing below the bladder are the key components of basic practices. PMID:26918162
Space environment induced mutations prefer to occur at polymorphic sites of rice genomes
NASA Astrophysics Data System (ADS)
Li, Y.; Liu, M.; Cheng, Z.; Sun, Y.
To explore the genomic characteristics of rice mutants induced by space environment, space-induced mutants 971-5, 972-4, and R955, which acquired new traits after space flight such as increased yield, reduced resistance to rice blast, and semi-dwarfism compared with their on-ground controls, 971ck, 972ck, and Bing95-503, respectively, together with other 8 japonica and 3 indica rice varieties, 17 in total, were analyzed by amplified fragment length polymorphism (AFLP) method. We chose 16 AFLP primer-pairs which generated a total of 1251 sites, of which 745 (59.6%) were polymorphic over all the genotypes. With the 16 pairs of primer combinations, 54 space-induced mutation sites were observed in 971-5, 86 in 972-4, and 5 in R955 compared to their controls, and the mutation rates were 4.3%, 6.9% and 0.4%, respectively. Interestingly, 75.9%, 84.9% and 100% of the mutation sites identified in 971-5, 972-4, and R955 occurred in polymorphic sites. This result suggests that the space environment preferentially induced mutations at polymorphic sites in rice genomes and might share a common mechanism with other types of mutagens. It also implies that polymorphic sites in genomes are potential "hotspots" for mutations induced by the space environment.
White Pine Site Index for the Southern Forest Survey
Bernard R. Parresol; John S. Vissage
1998-01-01
Second-growth white pine age-height data a A base-ageinvariant polymorphic site index equation was used to model the white pine (Pinus strobus L.) site-quality data provided by Frothingham (1914). These data are the accepted standard used by the Southern Forest Inventory and Analysis unit of the U.S. Department of Agriculture, Forest Service. An all...
Recurrent selection on the Winters sex-ratio genes in Drosophila simulans.
Kingan, Sarah B; Garrigan, Daniel; Hartl, Daniel L
2010-01-01
Selfish genes, such as meiotic drive elements, propagate themselves through a population without increasing the fitness of host organisms. X-linked (or Y-linked) meiotic drive elements reduce the transmission of the Y (X) chromosome and skew progeny and population sex ratios, leading to intense conflict among genomic compartments. Drosophila simulans is unusual in having a least three distinct systems of X chromosome meiotic drive. Here, we characterize naturally occurring genetic variation at the Winters sex-ratio driver (Distorter on the X or Dox), its progenitor gene (Mother of Dox or MDox), and its suppressor gene (Not Much Yang or Nmy), which have been previously mapped and characterized. We survey three North American populations as well as 13 globally distributed strains and present molecular polymorphism data at the three loci. We find that all three genes show signatures of selection in North America, judging from levels of polymorphism and skews in the site-frequency spectrum. These signatures likely result from the biased transmission of the driver and selection on the suppressor for the maintenance of equal sex ratios. Coalescent modeling indicates that the timing of selection is more recent than the age of the alleles, suggesting that the driver and suppressor are coevolving under an evolutionary "arms race." None of the Winters sex-ratio genes are fixed in D. simulans, and at all loci we find ancestral alleles, which lack the gene insertions and exhibit high levels of nucleotide polymorphism compared to the derived alleles. In addition, we find several "null" alleles that have mutations on the derived Dox background, which result in loss of drive function. We discuss the possible causes of the maintenance of presence-absence polymorphism in the Winters sex-ratio genes.
Gene-Based Single Nucleotide Polymorphism Markers for Genetic and Association Mapping in Common Bean
2012-01-01
Background In common bean, expressed sequence tags (ESTs) are an underestimated source of gene-based markers such as insertion-deletions (Indels) or single-nucleotide polymorphisms (SNPs). However, due to the nature of these conserved sequences, detection of markers is difficult and portrays low levels of polymorphism. Therefore, development of intron-spanning EST-SNP markers can be a valuable resource for genetic experiments such as genetic mapping and association studies. Results In this study, a total of 313 new gene-based markers were developed at target genes. Intronic variation was deeply explored in order to capture more polymorphism. Introns were putatively identified after comparing the common bean ESTs with the soybean genome, and the primers were designed over intron-flanking regions. The intronic regions were evaluated for parental polymorphisms using the single strand conformational polymorphism (SSCP) technique and Sequenom MassARRAY system. A total of 53 new marker loci were placed on an integrated molecular map in the DOR364 × G19833 recombinant inbred line (RIL) population. The new linkage map was used to build a consensus map, merging the linkage maps of the BAT93 × JALO EEP558 and DOR364 × BAT477 populations. A total of 1,060 markers were mapped, with a total map length of 2,041 cM across 11 linkage groups. As a second application of the generated resource, a diversity panel with 93 genotypes was evaluated with 173 SNP markers using the MassARRAY-platform and KASPar technology. These results were coupled with previous SSR evaluations and drought tolerance assays carried out on the same individuals. This agglomerative dataset was examined, in order to discover marker-trait associations, using general linear model (GLM) and mixed linear model (MLM). Some significant associations with yield components were identified, and were consistent with previous findings. Conclusions In short, this study illustrates the power of intron-based markers for linkage and association mapping in common bean. The utility of these markers is discussed in relation with the usefulness of microsatellites, the molecular markers by excellence in this crop. PMID:22734675
Prokofieva, Margarita; Karadima, Georgia; Koukia, Evmorfia; Michou, Vassiliki; Kyprianidou, Chrysoula; Papageorgiou, Chrysovalantis V; Alexiadis, Evangelos; Constantoulakis, Pantelis; Dikeos, Dimitris
2017-10-01
The aim of this study is to investigate whether a 44-base-pair insertion/deletion polymorphism in the upstream regulatory region of the serotonin transporter gene (5-HTTLPR) is associated with the nursing diagnoses and the achievement of the desired nursing outcomes in inpatients with major depression. Thirty five patients were evaluated. The nursing diagnoses of risk for suicide and imbalanced nutrition are reported less often in homozygotes of the high-expressing gene (L A ). Carriers of the low-expressing genes (L G or S) have a worse response to interventions which aim to increase low self-esteem, indicating that they may need more intensive care in order to achieve the desired outcome. Genetics in psychiatric nursing could help refine personalized care, however further studies with large sample sizes and multiple gene evaluations are needed.
Makris, T K; Stavroulakis, G A; Dafni, U G; Gialeraki, A E; Krespi, P G; Hatzizacharias, A N; Tsoukala, C G; Vythoulkas, J S; Kyriakidis, M K
2000-11-01
Angiotensin-converting enzyme (ACE) gene polymorphism has been associated with an increased incidence of myocardial infarction. Recent studies have investigated a potential influence of ACE gene polymorphism on fibrinolysis or endothelial function. It has been previously established that essential hypertension is accompanied by endothelial dysfunction and fibrinolytic balance disorders. The aim of our study was to study the relation between ACE gene polymorphism and fibrinolytic/hemostatic factors as well as endothelial cell damage markers in patients with hypertension. The following parameters were evaluated in 104 patients with previously untreated hypertension: plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) antigen, fibrinogen, D-dimer, and von Willebrand factor (vWF). The genotype of the ACE gene was also determined (by the polymerase chain reaction method), and patients were characterized according to the observed alleles as deletion/deletion (DD), insertion/insertion (II), or insertion/deletion (ID). Those with DD genotype (n = 42) had significantly higher plasma levels of PAI-1 antigen (P =. 012), tPA antigen (P =.0001), fibrinogen (P =.0002), D-dimer (P =. 0001) and vWF (P =.0004) compared with ID (n = 30) or II (n = 32) genotypes. The ACE gene genotypes appeared to be significant predictors for plasma PAI-1 antigen, tPA antigen, fibrinogen, D -dimer, and vWF even after adjustment for age, sex, body mass index, triglyceride and cholesterol levels, and blood pressure. Our findings suggest that the ACE/DD genotype is associated with hemostasis balance disturbances reflecting hypercoagulability and endothelial damage in patients with untreated hypertension.
Rivera-Torres, Natalia; Banas, Kelly; Bialk, Pawel; Bloh, Kevin M; Kmiec, Eric B
2017-01-01
CRISPR/Cas9 and single-stranded DNA oligonucleotides (ssODNs) have been used to direct the repair of a single base mutation in human genes. Here, we examine a method designed to increase the precision of RNA guided genome editing in human cells by utilizing a CRISPR/Cas9 ribonucleoprotein (RNP) complex to initiate DNA cleavage. The RNP is assembled in vitro and induces a double stranded break at a specific site surrounding the mutant base designated for correction by the ssODN. We use an integrated mutant eGFP gene, bearing a single base change rendering the expressed protein nonfunctional, as a single copy target in HCT 116 cells. We observe significant gene correction activity of the mutant base, promoted by the RNP and single-stranded DNA oligonucleotide with validation through genotypic and phenotypic readout. We demonstrate that all individual components must be present to obtain successful gene editing. Importantly, we examine the genotype of individually sorted corrected and uncorrected clonally expanded cell populations for the mutagenic footprint left by the action of these gene editing tools. While the DNA sequence of the corrected population is exact with no adjacent sequence modification, the uncorrected population exhibits heterogeneous mutagenicity with a wide variety of deletions and insertions surrounding the target site. We designate this type of DNA aberration as on-site mutagenicity. Analyses of two clonal populations bearing specific DNA insertions surrounding the target site, indicate that point mutation repair has occurred at the level of the gene. The phenotype, however, is not rescued because a section of the single-stranded oligonucleotide has been inserted altering the reading frame and generating truncated proteins. These data illustrate the importance of analysing mutagenicity in uncorrected cells. Our results also form the basis of a simple model for point mutation repair directed by a short single-stranded DNA oligonucleotides and CRISPR/Cas9 ribonucleoprotein complex.
Rivera-Torres, Natalia; Bialk, Pawel; Bloh, Kevin M.; Kmiec, Eric B.
2017-01-01
CRISPR/Cas9 and single-stranded DNA oligonucleotides (ssODNs) have been used to direct the repair of a single base mutation in human genes. Here, we examine a method designed to increase the precision of RNA guided genome editing in human cells by utilizing a CRISPR/Cas9 ribonucleoprotein (RNP) complex to initiate DNA cleavage. The RNP is assembled in vitro and induces a double stranded break at a specific site surrounding the mutant base designated for correction by the ssODN. We use an integrated mutant eGFP gene, bearing a single base change rendering the expressed protein nonfunctional, as a single copy target in HCT 116 cells. We observe significant gene correction activity of the mutant base, promoted by the RNP and single-stranded DNA oligonucleotide with validation through genotypic and phenotypic readout. We demonstrate that all individual components must be present to obtain successful gene editing. Importantly, we examine the genotype of individually sorted corrected and uncorrected clonally expanded cell populations for the mutagenic footprint left by the action of these gene editing tools. While the DNA sequence of the corrected population is exact with no adjacent sequence modification, the uncorrected population exhibits heterogeneous mutagenicity with a wide variety of deletions and insertions surrounding the target site. We designate this type of DNA aberration as on-site mutagenicity. Analyses of two clonal populations bearing specific DNA insertions surrounding the target site, indicate that point mutation repair has occurred at the level of the gene. The phenotype, however, is not rescued because a section of the single-stranded oligonucleotide has been inserted altering the reading frame and generating truncated proteins. These data illustrate the importance of analysing mutagenicity in uncorrected cells. Our results also form the basis of a simple model for point mutation repair directed by a short single-stranded DNA oligonucleotides and CRISPR/Cas9 ribonucleoprotein complex. PMID:28052104
2012-01-01
Introduction Catheter-related bloodstream infections (CRBSIs) associated with short-term central venous catheters (CVCs) in intensive care unit (ICU) patients are a major clinical problem. Bacterial colonization of the skin at the CVC insertion site is an important etiologic factor for CRBSI. The aim of this study was to assess the efficacy of medical-grade honey in reducing bacterial skin colonization at insertion sites. Methods A prospective, single-center, open-label randomized controlled trial was performed at the ICU of a university hospital in The Netherlands to assess the efficacy of medical-grade honey to reduce skin colonization of insertion sites. Medical-grade honey was applied in addition to standard CVC-site dressing and disinfection with 0.5% chlorhexidine in 70% alcohol. Skin colonization was assessed on a daily basis before CVC-site disinfection. The primary end point was colonization of insertion sites with >100 colony-forming units at the last sampling before removal of the CVC or transfer of the patient from the ICU. Secondary end points were quantitative levels of colonization of the insertion sites and colonization of insertion sites stratified for CVC location. Results Colonization of insertion sites was not affected by the use of medical-grade honey, as 44 (34%) of 129 and 36 (34%) of 106 patients in the honey and standard care groups, respectively, had a positive skin culture (P = 0.98). Median levels of skin colonization at the last sampling were 1 (0 to 2.84) and 1 (0 to 2.70) log colony-forming units (CFUs)/swab for the honey and control groups, respectively (P = 0.94). Gender, days of CVC placement, CVC location, and CVC type were predictive for a positive skin culture. Correction for these variables did not change the effect of honey on skin-culture positivity. Conclusions Medical-grade honey does not affect colonization of the skin at CVC insertion sites in ICU patients when applied in addition to standard disinfection with 0.5% chlorhexidine in 70% alcohol. Trial registration Netherlands Trial Registry, NTR1652. PMID:23111148
Kwakman, Paulus H; Müller, Marcella C; Binnekade, Jan M; van den Akker, Johannes P; de Borgie, Corianne A; Schultz, Marcus J; Zaat, Sebastian A
2012-10-30
Catheter-related bloodstream infections (CRBSIs) associated with short-term central venous catheters (CVCs) in intensive care unit (ICU) patients are a major clinical problem. Bacterial colonization of the skin at the CVC insertion site is an important etiologic factor for CRBSI. The aim of this study was to assess the efficacy of medical-grade honey in reducing bacterial skin colonization at insertion sites. A prospective, single-center, open-label randomized controlled trial was performed at the ICU of a university hospital in The Netherlands to assess the efficacy of medical-grade honey to reduce skin colonization of insertion sites. Medical-grade honey was applied in addition to standard CVC-site dressing and disinfection with 0.5% chlorhexidine in 70% alcohol. Skin colonization was assessed on a daily basis before CVC-site disinfection. The primary end point was colonization of insertion sites with >100 colony-forming units at the last sampling before removal of the CVC or transfer of the patient from the ICU. Secondary end points were quantitative levels of colonization of the insertion sites and colonization of insertion sites stratified for CVC location. Colonization of insertion sites was not affected by the use of medical-grade honey, as 44 (34%) of 129 and 36 (34%) of 106 patients in the honey and standard care groups, respectively, had a positive skin culture (P = 0.98). Median levels of skin colonization at the last sampling were 1 (0 to 2.84) and 1 (0 to 2.70) log colony-forming units (CFUs)/swab for the honey and control groups, respectively (P = 0.94). Gender, days of CVC placement, CVC location, and CVC type were predictive for a positive skin culture. Correction for these variables did not change the effect of honey on skin-culture positivity. Medical-grade honey does not affect colonization of the skin at CVC insertion sites in ICU patients when applied in addition to standard disinfection with 0.5% chlorhexidine in 70% alcohol. Netherlands Trial Registry, NTR1652.
Zhao, Jie-hong; Zhang, Ji-shun; Wang, Yi; Wang, Ren-gang; Wu, Chun; Fan, Long-jiang; Ren, Xue-liang
2011-11-01
DNA methylation plays an important role in the epigenetic regulation of gene expression during plant growth, development, and polyploidization. However, there is still no distinct evidence in tobacco regarding the distribution of the methylation pattern and whether it contributes to qualitative characteristics. We studied the levels and patterns of methylation polymorphism at CCGG sites in 48 accessions of allotetraploid flue-cured tobacco, Nicotiana tabacum, using a methylation-sensitive amplified polymorphism (MSAP) technique. The results showed that methylation existed at a high level among tobacco accessions, among which 49.3% sites were methylated and 69.9% allelic sites were polymorphic. A cluster analysis revealed distinct patterns of geography-specific groups. In addition, three polymorphic sites significantly related to tobacco mosaic virus (TMV) resistance were explored. This suggests that tobacco breeders should pay more attention to epigenetic traits.
Dubiley, Svetlana; Kirillov, Eugene; Ignatova, Anna; Stepanshina, Valentina; Shemyakin, Igor
2007-01-01
We analyzed IS6110-associated polymorphisms in the phospholipase C genes of 107 isolates of Mycobacterium tuberculosis selected to be representative of isolates circulating in central Russia. We found that the majority of Latin American-Mediterranean family strains contained an insertion in a unique position in the plcA gene, suggesting a common ancestor. This insertion can serve as a specific genetic marker for this group, which we designate the LAM-RUS family. PMID:17942651
Dettenkofer, M; Wilson, C; Gratwohl, A; Schmoor, C; Bertz, H; Frei, R; Heim, D; Luft, D; Schulz, S; Widmer, A F
2010-06-01
To compare the efficacy of two commercially available, alcohol-based antiseptic solutions for preparation and care of central venous catheter (CVC) insertion sites, with and without octenidine dihydrochloride, a double-blind, randomized, controlled trial was undertaken in the haematology units and in one surgical unit of two university hospitals. Adult patients with a non-tunnelled CVC were randomly assigned to two different skin disinfection regimens at the insertion site: 0.1% octenidine with 30% 1-propanol and 45% 2-propanol, and as control 74% ethanol with 10% 2-propanol. Endpoints were (i) skin colonization at the insertion site; (ii) positive culture from the catheter tip (> or = 15 CFU); and (iii) occurrence of CVC-associated bloodstream infection (defined according to criteria set by the CDC). Four hundred patients with inserted CVC were enrolled from May 2002 through April 2005. Both groups were similar in respect of patient characteristics and co-morbidities. Skin colonization at the CVC insertion site during the first 10 days was significantly reduced by octenidine treatment (relative difference octenidine vs. control: 0.21; 95%CI: 0.11-0.39, p <0.0001). Positive culture of the catheter tip was significantly less frequent in the octenidine group (7.9%) than in the control group (17.8%): OR = 0.39 (95%CI: 0.20-0.80, p 0.009). Patients treated with octenidine had a non-significant reduction in catheter-associated bloodstream infections (4.1% vs. 8.3%; OR = 0.44; 95%CI: 0.18-1.08, p 0.081). Side effects were similar in both groups. This randomized controlled trial supports the results of two observational studies demonstrating octenidine in alcoholic solution to be a better option than alcohol alone for the prevention of CVC-associated infections.
Boakes, E.; Kearns, A. M.; Ganner, M.; Perry, C.; Hill, R. L.; Ellington, M. J.
2011-01-01
Genetically diverse community-associated methicillin resistant Staphylococcus aureus (CA-MRSA) can harbor a bacteriophage encoding Panton-Valentine leukocidin (PVL) lysogenized into its chromosome (prophage). Six PVL phages (ΦPVL, Φ108PVL, ΦSLT, ΦSa2MW, ΦSa2USA, and ΦSa2958) are known, and single-nucleotide polymorphisms (SNPs) in the PVL genes have been reported. We sought to determine the distribution of lysogenized PVL phages among MRSA strains with PVL (PVL-MRSA strains), the PVL gene sequences, and the chromosomal phage insertion sites in 114 isolates comprising nine clones of PVL-MRSA that were selected for maximal underlying genetic diversity. The six PVL phages were identified by PCR; ΦSa2USA was present in the highest number of different lineages (multilocus sequence type clonal complex 1 [CC1], CC5, CC8, and sequence type 93 [ST93]) (n = 37 isolates). Analysis of 92 isolates confirmed that PVL phages inserted into the same chromosomal insertion locus in CC22, -30, and -80 but in a different locus in isolates of CC1, -5, -8, -59, and -88 and ST93 (and CC22 in two isolates). Within the two different loci, specific attachment motifs were found in all cases, although some limited inter- and intralineage sequence variation occurred. Overall, lineage-specific relationships between the PVL phage, the genes that encode the toxin, and the position at which the phage inserts into the host chromosome were identified. These analyses provide important insights into the microepidemiology of PVL-MRSA, will prove a valuable adjunct in outbreak investigation, and may help predict the emergence of new strains. PMID:21106787
Kampf, Günter; Reise, Gesche; James, Claudia; Gittelbauer, Kirsten; Gosch, Jutta; Alpers, Birgit
2013-01-01
Background: Peripheral venous catheters are frequently used in hospitalized patients but increase the risk of nosocomial bloodstream infection. Evidence-based guidelines describe specific steps that are known to reduce infection risk. However, the degree of guideline implementation in clinical practice is not known. The aim of this study was to determine the use of specific steps for insertion of peripheral venous catheters in clinical practice and to implement a multimodal intervention aimed at improving both compliance and the optimum order of the steps. Methods: The study was conducted at University Hospital Hamburg. An optimum procedure for inserting a peripheral venous catheter was defined based on three evidence-based guidelines (WHO, CDC, RKI) including five steps with 1A or 1B level of evidence: hand disinfection before patient contact, skin antisepsis of the puncture site, no palpation of treated puncture site, hand disinfection before aseptic procedure, and sterile dressing on the puncture site. A research nurse observed and recorded procedures for peripheral venous catheter insertion for healthcare workers in four different departments (endoscopy, central emergency admissions, pediatrics, and dermatology). A multimodal intervention with 5 elements was established (teaching session, dummy training, e-learning tool, tablet and poster, and direct feedback), followed by a second observation period. During the last observation week, participants evaluated the intervention. Results: In the control period, 207 insertions were observed, and 202 in the intervention period. Compliance improved significantly for four of five steps (e.g., from 11.6% to 57.9% for hand disinfection before patient contact; p<0.001, chi-square test). Compliance with skin antisepsis of the puncture site was high before and after intervention (99.5% before and 99.0% after). Performance of specific steps in the correct order also improved (e.g., from 7.7% to 68.6% when three of five steps were done; p<0.001). The intervention was described as helpful by 46.8% of the participants, as neutral by 46.8%, and as disruptive by 6.4%. Conclusions: A multimodal strategy to improve both compliance with safety steps for peripheral venous catheter insertion and performance of an optimum procedure was effective and was regarded helpful by healthcare workers. PMID:24327944
In and out of the rRNA genes: characterization of Pokey elements in the sequenced Daphnia genome
2013-01-01
Background Only a few transposable elements are known to exhibit site-specific insertion patterns, including the well-studied R-element retrotransposons that insert into specific sites within the multigene rDNA. The only known rDNA-specific DNA transposon, Pokey (superfamily: piggyBac) is found in the freshwater microcrustacean, Daphnia pulex. Here, we present a genome-wide analysis of Pokey based on the recently completed whole genome sequencing project for D. pulex. Results Phylogenetic analysis of Pokey elements recovered from the genome sequence revealed the presence of four lineages corresponding to two divergent autonomous families and two related lineages of non-autonomous miniature inverted repeat transposable elements (MITEs). The MITEs are also found at the same 28S rRNA gene insertion site as the Pokey elements, and appear to have arisen as deletion derivatives of autonomous elements. Several copies of the full-length Pokey elements may be capable of producing an active transposase. Surprisingly, both families of Pokey possess a series of 200 bp repeats upstream of the transposase that is derived from the rDNA intergenic spacer (IGS). The IGS sequences within the Pokey elements appear to be evolving in concert with the rDNA units. Finally, analysis of the insertion sites of Pokey elements outside of rDNA showed a target preference for sites similar to the specific sequence that is targeted within rDNA. Conclusions Based on the target site preference of Pokey elements and the concerted evolution of a segment of the element with the rDNA unit, we propose an evolutionary path by which the ancestors of Pokey elements have invaded the rDNA niche. We discuss how specificity for the rDNA unit may have evolved and how this specificity has played a role in the long-term survival of these elements in the subgenus Daphnia. PMID:24059783
QuickMap: a public tool for large-scale gene therapy vector insertion site mapping and analysis.
Appelt, J-U; Giordano, F A; Ecker, M; Roeder, I; Grund, N; Hotz-Wagenblatt, A; Opelz, G; Zeller, W J; Allgayer, H; Fruehauf, S; Laufs, S
2009-07-01
Several events of insertional mutagenesis in pre-clinical and clinical gene therapy studies have created intense interest in assessing the genomic insertion profiles of gene therapy vectors. For the construction of such profiles, vector-flanking sequences detected by inverse PCR, linear amplification-mediated-PCR or ligation-mediated-PCR need to be mapped to the host cell's genome and compared to a reference set. Although remarkable progress has been achieved in mapping gene therapy vector insertion sites, public reference sets are lacking, as are the possibilities to quickly detect non-random patterns in experimental data. We developed a tool termed QuickMap, which uniformly maps and analyzes human and murine vector-flanking sequences within seconds (available at www.gtsg.org). Besides information about hits in chromosomes and fragile sites, QuickMap automatically determines insertion frequencies in +/- 250 kb adjacency to genes, cancer genes, pseudogenes, transcription factor and (post-transcriptional) miRNA binding sites, CpG islands and repetitive elements (short interspersed nuclear elements (SINE), long interspersed nuclear elements (LINE), Type II elements and LTR elements). Additionally, all experimental frequencies are compared with the data obtained from a reference set, containing 1 000 000 random integrations ('random set'). Thus, for the first time a tool allowing high-throughput profiling of gene therapy vector insertion sites is available. It provides a basis for large-scale insertion site analyses, which is now urgently needed to discover novel gene therapy vectors with 'safe' insertion profiles.
Shukla, Sanjay K; Kislow, Jennifer; Briska, Adam; Henkhaus, John; Dykes, Colin
2009-09-01
Staphylococcus aureus is a highly versatile and evolving bacterium of great clinical importance. S. aureus can evolve by acquiring single nucleotide polymorphisms and mobile genetic elements and by recombination events. Identification and location of novel genomic elements in a bacterial genome are not straightforward, unless the whole genome is sequenced. Optical mapping is a new tool that creates a high-resolution, in situ ordered restriction map of a bacterial genome. These maps can be used to determine genomic organization and perform comparative genomics to identify genomic rearrangements, such as insertions, deletions, duplications, and inversions, compared to an in silico (virtual) restriction map of a known genome sequence. Using this technology, we report here the identification, approximate location, and characterization of a genetic inversion of approximately 500 kb of a DNA element between the NRS387 (USA800) and FPR3757 (USA300) strains. The presence of the inversion and location of its junction sites were confirmed by site-specific PCR and sequencing. At both the left and right junction sites in NRS387, an IS1181 element and a 73-bp sequence were identified as inverted repeats, which could explain the possible mechanism of the inversion event.
Wang, Qingguo; Jia, Peilin; Zhao, Zhongming
2015-01-01
Fueled by widespread applications of high-throughput next generation sequencing (NGS) technologies and urgent need to counter threats of pathogenic viruses, large-scale studies were conducted recently to investigate virus integration in host genomes (for example, human tumor genomes) that may cause carcinogenesis or other diseases. A limiting factor in these studies, however, is rapid virus evolution and resulting polymorphisms, which prevent reads from aligning readily to commonly used virus reference genomes, and, accordingly, make virus integration sites difficult to detect. Another confounding factor is host genomic instability as a result of virus insertions. To tackle these challenges and improve our capability to identify cryptic virus-host fusions, we present a new approach that detects Virus intEgration sites through iterative Reference SEquence customization (VERSE). To the best of our knowledge, VERSE is the first approach to improve detection through customizing reference genomes. Using 19 human tumors and cancer cell lines as test data, we demonstrated that VERSE substantially enhanced the sensitivity of virus integration site detection. VERSE is implemented in the open source package VirusFinder 2 that is available at http://bioinfo.mc.vanderbilt.edu/VirusFinder/.
Zhao, Jie-hong; Zhang, Ji-shun; Wang, Yi; Wang, Ren-gang; Wu, Chun; Fan, Long-jiang; Ren, Xue-liang
2011-01-01
DNA methylation plays an important role in the epigenetic regulation of gene expression during plant growth, development, and polyploidization. However, there is still no distinct evidence in tobacco regarding the distribution of the methylation pattern and whether it contributes to qualitative characteristics. We studied the levels and patterns of methylation polymorphism at CCGG sites in 48 accessions of allotetraploid flue-cured tobacco, Nicotiana tabacum, using a methylation-sensitive amplified polymorphism (MSAP) technique. The results showed that methylation existed at a high level among tobacco accessions, among which 49.3% sites were methylated and 69.9% allelic sites were polymorphic. A cluster analysis revealed distinct patterns of geography-specific groups. In addition, three polymorphic sites significantly related to tobacco mosaic virus (TMV) resistance were explored. This suggests that tobacco breeders should pay more attention to epigenetic traits. PMID:22042659
Kristjansdottir, G; Sandling, J K; Bonetti, A; Roos, I M; Milani, L; Wang, C; Gustafsdottir, S M; Sigurdsson, S; Lundmark, A; Tienari, P J; Koivisto, K; Elovaara, I; Pirttilä, T; Reunanen, M; Peltonen, L; Saarela, J; Hillert, J; Olsson, T; Landegren, U; Alcina, A; Fernández, O; Leyva, L; Guerrero, M; Lucas, M; Izquierdo, G; Matesanz, F; Syvänen, A-C
2008-01-01
Background: IRF5 is a transcription factor involved both in the type I interferon and the toll-like receptor signalling pathways. Previously, IRF5 has been found to be associated with systemic lupus erythematosus, rheumatoid arthritis and inflammatory bowel diseases. Here we investigated whether polymorphisms in the IRF5 gene would be associated with yet another disease with features of autoimmunity, multiple sclerosis (MS). Methods: We genotyped nine single nucleotide polymorphisms and one insertion-deletion polymorphism in the IRF5 gene in a collection of 2337 patients with MS and 2813 controls from three populations: two case–control cohorts from Spain and Sweden, and a set of MS trio families from Finland. Results: Two single nucleotide polymorphism (SNPs) (rs4728142, rs3807306), and a 5 bp insertion-deletion polymorphism located in the promoter and first intron of the IRF5 gene, showed association signals with values of p<0.001 when the data from all cohorts were combined. The predisposing alleles were present on the same common haplotype in all populations. Using electrophoretic mobility shift assays we observed allele specific differences in protein binding for the SNP rs4728142 and the 5 bp indel, and by a proximity ligation assay we demonstrated increased binding of the transcription factor SP1 to the risk allele of the 5 bp indel. Conclusion: These findings add IRF5 to the short list of genes shown to be associated with MS in more than one population. Our study adds to the evidence that there might be genes or pathways that are common in multiple autoimmune diseases, and that the type I interferon system is likely to be involved in the development of these diseases. PMID:18285424
Turhan, N K; Ilikhan, S Uygun; Hamamcioglu, A C; Ustundag, Y; Dursun, A; Kokturk, F
2015-12-16
Chronic viral hepatitis B, chronic viral hepatitis C, non-alcoholic steatohepatitis, alcoholic liver disease, autoimmune hepatitis, primary biliary cirrhosis, and secondary biliary cirrhosis are important health issues worldwide. While an association between angiotensin-converting enzyme gene insertion/deletion (ACE gene I/D) polymorphism and liver fibrosis has been demonstrated in rat studies, the results of clinical studies area have been contradictory. The aim of this study was to assess the possible association between ACE gene I/D polymorphism and liver fibrosis in a large group of Turkish patients from the western Black Sea region. In 418 patients with different etiologies, ACE gene I/D polymorphism and serum ACE levels were investigated. The distribution of the "DD", "ID", "II" genotypes of the ACE gene were 32.5, 48.8, and 18.7% in the mild to moderate fibrosis group (N = 246, F:1-3 according to Ishak's score) and 39.0, 44.2, and 16.9% in the advanced fibrosis group (N = 172, F:4-6 according to Ishak's score). A significant correlation between serum ACE levels and ACE gene alleles was identified (P < 0.001): serum ACE levels of patients with D alleles were higher than those of patients with I alleles [44 (min 7-max 101) versus 29 (min 7-max 96)]. Patients with advanced fibrosis were also found to be older than those with mild to moderate fibrosis (P < 0.001). No significant association was noted between the patient gender and fibrosis severity. We conclude that ACE I/D polymorphism is not associated with the degree of liver fibrosis.
Functional impact of the human mobilome.
Babatz, Timothy D; Burns, Kathleen H
2013-06-01
The human genome is replete with interspersed repetitive sequences derived from the propagation of mobile DNA elements. Three families of human retrotransposons remain active today: LINE1, Alu, and SVA elements. Since 1988, de novo insertions at previously recognized disease loci have been shown to generate highly penetrant alleles in Mendelian disorders. Only recently has the extent of germline-transmitted retrotransposon insertion polymorphism (RIP) in human populations been fully realized. Also exciting are recent studies of somatic retrotransposition in human tissues and reports of tumor-specific insertions, suggesting roles in tissue heterogeneity and tumorigenesis. Here we discuss mobile elements in human disease with an emphasis on exciting developments from the last several years. Copyright © 2013 Elsevier Ltd. All rights reserved.
Microscopic origin of entropy-driven polymorphism in hybrid organic-inorganic perovskite materials
NASA Astrophysics Data System (ADS)
Butler, Keith T.; Svane, Katrine; Kieslich, Gregor; Cheetham, Anthony K.; Walsh, Aron
2016-11-01
Entropy is a critical, but often overlooked, factor in determining the relative stabilities of crystal phases. The importance of entropy is most pronounced in softer materials, where small changes in free energy can drive phase transitions, which has recently been demonstrated in the case of organic-inorganic hybrid-formate perovskites. In this Rapid Communication we demonstrate the interplay between composition and crystal structure that is responsible for the particularly pronounced role of entropy in determining polymorphism in hybrid organic-inorganic materials. Using ab initio based lattice dynamics, we probe the origins and effects of vibrational entropy of four archetype perovskite (A B X3 ) structures. We consider an inorganic material (SrTiO3), an A -site hybrid-halide material (CH3NH3) PbI3 , a X -site hybrid material KSr (BH4)3 , and a mixed A - and X -site hybrid-formate material (N2H5) Zn (HCO2)3 , comparing the differences in entropy between two common polymorphs. The results demonstrate the importance of low-frequency intermolecular modes in determining the phase stability in these materials. The understanding gained allows us to propose a general principle for the relative stability of different polymorphs of hybrid materials as temperature is increased.
Prospects and limitations for p-type doping in boron nitride polymorphs
NASA Astrophysics Data System (ADS)
Weston, Leigh; van de Walle, Chris G.
Using first-principles calculations, we examine the potential for p-type doping of BN polymorphs via substitutional impurities. Based on density functional theory with a hybrid functional, our calculations reveal that group-IV elements (C, Si) substituting at the N site result in acceptor levels that are more than 1 eV above the valence-band maximum in all of the BN polymorphs, and hence far too deep to allow for p-type doping. On the other hand, group-II elements (Be, Mg) substituting at the B site lead to shallower acceptor levels. However, for the ground-state hexagonal phase (h-BN), we show that p-type doping at the B site is inhibited by the formation of hole polarons. Our calculations reveal that hole localization is intrinsic to sp2 bonded h-BN, and this places fundamental limits on hole conduction in this material. In contrast, the sp3 bonded wurtzite (w-BN) and cubic (c-BN) polymorphs are capable of forming shallow acceptor levels. For Be dopants, the acceptor ionization energies are 0.31 eV and 0.24 eV for w-BN and c-BN, respectively; these values are only slightly larger than the ionization energy of the Mg acceptor in GaN. This work was supported by NSF.
Rueda, P; Hurtado, A; del Barrio, M; Martínez-Torrecuadrada, J L; Kamstrup, S; Leclerc, C; Casal, J I
1999-10-10
An antigen-delivery system based on hybrid virus-like particles (VLPs) formed by the self-assembly of the capsid VP2 protein of canine parvovirus (CPV) and expressing foreign peptides was investigated. In this report, we have studied the effects of inserting the poliovirus C3:B epitope in the four loops and the C terminus of the CPV VP2 on the particle structure and immunogenicity. Epitope insertions in the four loops allowed the recovery of capsids in all of the mutants. However, only insertions of the C3:B epitope in VP2 residue 225 of the loop 2 were able to elicit a significant anti-peptide antibody response, but not poliovirus-neutralizing antibodies, probably because residue 225 is located in an small depression of the surface. To fine modulate the insertion site in loop 2, a cassette-mutagenesis was carried out to insert the epitope in adjacent positions 226, 227, and 228. The epitope C3:B inserted into these positions was well recognized by the specific monoclonal antibody C3 by immunoelectron microscopy. BALB/c mice immunized with these chimeric C3:B CPV:VLPs were able to elicit an strong neutralizing antibody response (>3 log(10) units) against poliovirus type 1 (Mahoney strain). Therefore, minor displacements in the insertion place cause dramatic changes in the accessibility of the epitope and the induction of antibody responses. Copyright 1999 Academic Press.
Hsing, Michael; Cherkasov, Artem
2008-06-25
Insertions and deletions (indels) represent a common type of sequence variations, which are less studied and pose many important biological questions. Recent research has shown that the presence of sizable indels in protein sequences may be indicative of protein essentiality and their role in protein interaction networks. Examples of utilization of indels for structure-based drug design have also been recently demonstrated. Nonetheless many structural and functional characteristics of indels remain less researched or unknown. We have created a web-based resource, Indel PDB, representing a structural database of insertions/deletions identified from the sequence alignments of highly similar proteins found in the Protein Data Bank (PDB). Indel PDB utilized large amounts of available structural information to characterize 1-, 2- and 3-dimensional features of indel sites. Indel PDB contains 117,266 non-redundant indel sites extracted from 11,294 indel-containing proteins. Unlike loop databases, Indel PDB features more indel sequences with secondary structures including alpha-helices and beta-sheets in addition to loops. The insertion fragments have been characterized by their sequences, lengths, locations, secondary structure composition, solvent accessibility, protein domain association and three dimensional structures. By utilizing the data available in Indel PDB, we have studied and presented here several sequence and structural features of indels. We anticipate that Indel PDB will not only enable future functional studies of indels, but will also assist protein modeling efforts and identification of indel-directed drug binding sites.
Yabuuchi, Naoaki; Komaba, Shinichi
2014-01-01
Large-scale high-energy batteries with electrode materials made from the Earth-abundant elements are needed to achieve sustainable energy development. On the basis of material abundance, rechargeable sodium batteries with iron- and manganese-based positive electrode materials are the ideal candidates for large-scale batteries. In this review, iron- and manganese-based electrode materials, oxides, phosphates, fluorides, etc, as positive electrodes for rechargeable sodium batteries are reviewed. Iron and manganese compounds with sodium ions provide high structural flexibility. Two layered polymorphs, O3- and P2-type layered structures, show different electrode performance in Na cells related to the different phase transition and sodium migration processes on sodium extraction/insertion. Similar to layered oxides, iron/manganese phosphates and pyrophosphates also provide the different framework structures, which are used as sodium insertion host materials. Electrode performance and reaction mechanisms of the iron- and manganese-based electrode materials in Na cells are described and the similarities and differences with lithium counterparts are also discussed. Together with these results, the possibility of the high-energy battery system with electrode materials made from only Earth-abundant elements is reviewed. PMID:27877694
Yabuuchi, Naoaki; Komaba, Shinichi
2014-08-01
Large-scale high-energy batteries with electrode materials made from the Earth-abundant elements are needed to achieve sustainable energy development. On the basis of material abundance, rechargeable sodium batteries with iron- and manganese-based positive electrode materials are the ideal candidates for large-scale batteries. In this review, iron- and manganese-based electrode materials, oxides, phosphates, fluorides, etc, as positive electrodes for rechargeable sodium batteries are reviewed. Iron and manganese compounds with sodium ions provide high structural flexibility. Two layered polymorphs, O3- and P2-type layered structures, show different electrode performance in Na cells related to the different phase transition and sodium migration processes on sodium extraction/insertion. Similar to layered oxides, iron/manganese phosphates and pyrophosphates also provide the different framework structures, which are used as sodium insertion host materials. Electrode performance and reaction mechanisms of the iron- and manganese-based electrode materials in Na cells are described and the similarities and differences with lithium counterparts are also discussed. Together with these results, the possibility of the high-energy battery system with electrode materials made from only Earth-abundant elements is reviewed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campeau, E.; Leon-Del-Rio, A.; Gravel, R.A.
Propionic acidemia is a rare autosomal recessive disorder characterized by a deficiency of the mitochondrial biotin-dependent enzyme, propionyl-CoA carboxylase (PCC). PCC has the structure {alpha}{sub 4}{beta}{sub 4}, with the {alpha} subunit containing the biotin prosthetic group. This study is concerned with defining the spectrum of mutations occurring in the PCCA gene encoding the {alpha} subunit. Mutations were initially assigned to this gene through complementation experiments done after somatic fusion of patient fibroblasts. The analyses were performed on PCR-amplified reverse transcripts of fibroblast RNA. The mutations were identified by single strand conformational polymorphism analysis and direct sequencing of PCR products. Threemore » candidate disease-causing mutations and one DNA polymorphism were identified in the {alpha} subunit sequence in different patients: (1) a 3 bp deletion {triangle}CTG{sub 2058-2060}, which eliminates Cys687 near the biotin binding site (Lys669); (2) T{sub 611}{r_arrow}A which converts Met204 to Lys in a highly conserved region matching that of an ATP binding site; (3) An {approximately}50 bp deletion near the 3{prime} end of the cDNA which likely corresponds to the loss of an exon due to a splicing defect; and (4) a 3 bp insertion, +CAG{sub 2203}, located downstream of the stop codon, which is likely a DNA polymorphism. In order to determine the effect of the Cys687 deletion on the biotinylation of PCC, we expressed the mutation in a 67 amino acid C-terminal fragment of the PCC {alpha} subunit in E. coli in which biotinylation is directed by the bacterial biotin ligase. While the mutant peptide was expressed at about half-normal levels, the biotinylation of the peptide that was present was reduced to only {approximately}20% normal. We suggest, therefore, that the absence of PCC activity due to {triangle}Cys687 results at least in part from defective biotinylation of an unstable protein.« less
Williamson, Scott; Fledel-Alon, Adi; Bustamante, Carlos D
2004-09-01
We develop a Poisson random-field model of polymorphism and divergence that allows arbitrary dominance relations in a diploid context. This model provides a maximum-likelihood framework for estimating both selection and dominance parameters of new mutations using information on the frequency spectrum of sequence polymorphisms. This is the first DNA sequence-based estimator of the dominance parameter. Our model also leads to a likelihood-ratio test for distinguishing nongenic from genic selection; simulations indicate that this test is quite powerful when a large number of segregating sites are available. We also use simulations to explore the bias in selection parameter estimates caused by unacknowledged dominance relations. When inference is based on the frequency spectrum of polymorphisms, genic selection estimates of the selection parameter can be very strongly biased even for minor deviations from the genic selection model. Surprisingly, however, when inference is based on polymorphism and divergence (McDonald-Kreitman) data, genic selection estimates of the selection parameter are nearly unbiased, even for completely dominant or recessive mutations. Further, we find that weak overdominant selection can increase, rather than decrease, the substitution rate relative to levels of polymorphism. This nonintuitive result has major implications for the interpretation of several popular tests of neutrality.
[Analysis of Alu-insertion polymorphism in three subethnic groups of Kalmyks].
Khusainova, R I; Balinova, N V; Kutuev, I A; Spitsina, N Kh; Akhmetova, V L; Valiev, R R; Spitsyn, V A; Khusnutdinova, E K
2009-03-01
Eight Alu insertions at the NBC27, TPA25, NBC148, NBC123, ACE, APOA1, NBC51, and PV92 locus were examined in three subethnic groups of Kalmyks (Torgouds, Derbets, and Buzava). In general, the pattern of allele frequencies in Kalmyks was consistent with that in Asian populations of the world, and was similar to the Alu insertion frequencies pattern in Turkic populations of the Volga--Ural region and Central Asia. Pairwise comparisons of three subpopulations of Kalmyks with respect to the frequency distributions of eight Alu insertions revealed the differences between the groups examined. The coefficient of gene differentiation, F(st), constituted 1.37%, pointing to the common origin of the groups of interest, as well as to the uniformity of the gene pools of subethnic groups of Kalmyks examined.
Jóźków, Paweł; Słowińska-Lisowska, Małgorzata; Łaczmański, Łukasz; Mędraś, Marek
2013-01-01
Human behavior is influenced by a number of brain neurotransmitters. Central dopamine, serotonin and melanocortin systems have special importance for male sexual function. We searched for associations between male aging symptoms and polymorphic sites of serotonin (5-HTR1B), melanocortin (MC4R) and dopamine (DRD2, DRD4) receptors. In a population-based sample, genotyping of 5-HTR1B (polymorphism: G861C), MC4R (polymorphisms: C-2745T, Val103Ile), DRD2 (polymorphism: C313T) and DRD4 (polymorphism: 48-bp VNTR) was performed in 387 healthy men. The Aging Males' Symptoms (AMS) scale was used to evaluate specific ailments of aging men. We analyzed answers to questions from the AMS scale. Five points of the questionnaire addressed sexual symptoms of the aging male: feeling of passing one's peak, decrease in beard growth, decrease in ability/frequency to perform sexually, decrease in the number of morning erections, and decrease in sexual desire/libido (lacking pleasure in sex, lacking desire for sexual intercourse). Relations between reported symptoms and variants of the polymorphic sites of the studied genes were assessed. After adjusting for confounding factors (education, arterial hypertension, physical activity, weight, waist circumference) an association between the sexual dimension of AMS and genetic variants of 5-HTR1B G861C (p = 0.04) was observed. Variability of neurotransmitter receptor genes may be associated with sexual symptoms of aging in men. Copyright © 2013 S. Karger AG, Basel.
Structural organization and mutational analysis of the human uncoupling protein-2 (hUCP2) gene.
Tu, N; Chen, H; Winnikes, U; Reinert, I; Marmann, G; Pirke, K M; Lentes, K U
1999-01-01
Uncoupling proteins (UCPs) are mitochondrial membrane transporters which are involved in dissipating the proton electrochemical gradient thereby releasing stored energy as heat. This implies a major role of UCPs in energy metabolism and thermogenesis which when deregulated are key risk factors for the development of obesity and other eating disorders. From the three different human UCPs identified so far by gene cloning both UCP2 and UCP3 were mapped in close proximity (75-150 kb) to regions of human chromosome 11 (11q13) that have been linked to obesity and hyperinsulinaemia. At the amino acid level hUCP2 has about 55% identity to hUCP1 while hUCP3 is 71% identical to hUCP2. In this study we have deduced the genomic structure of the human UCP2 gene by PCR and direct sequence analysis. The hUCP2 gene spans over 8.7 kb distributed on 8 exons. The localization of the exon/intron boundaries within the coding region matches precisely that of the hUCP1 gene and is almost conserved in the recently discovered hUCP3 gene as well. The high degree of homology at the nucleotide level and the conservation of the exon /intron boundaries among the three UCP genes suggests that they may have evolved from a common ancestor or are the result from gene duplication events. Mutational analysis of the hUCP2 gene in a cohort of 172 children (aged 7 - 13) of Caucasian origin revealed a polymorphism in exon 4 (C to T transition at position 164 of the cDNA resulting in the substitution of an alanine by a valine at codon 55) and an insertion polymorphism in exon 8. The insertion polymorphism consists of a 45 bp repeat located 150 bp downstream of the stop codon in the 3'-UTR. The allele frequencies were 0.63 and 0.37 for the alanine and valine encoded alleles, respectively, and 0.71 versus 0.29 for the insertion polymorphism. The allele frequencies of both polymorphisms were not significantly elevated in a subgroup of 25 children characterized by low Resting Metabolic Rates (RMR). So far a direct correlation of the observed genotype with (RMR) and Body Mass Index (BMI) was not evident. Expression studies of the wild type and mutant forms of UCP2 should clarify the functional consequences these polymorphisms may have on energy metabolism and body weight regulation.
Işleten, Banu; Durmaz, Burak; Durmaz, Berrin; Onay, Hüseyin; Ozkınay, Ferda; Durmaz, Asude; Turan, Volkan; Oztekin, Kemal
2013-10-01
To investigate the association between C421T polymorphism within exon 4, C575T polymorphism within exon 6 of the RANK gene and bone mineral density (BMD) variations in postmenopausal Turkish women. One hundred seventy-eight postmenopausal women (patients = 100 and controls = 78) who applied to Ege University Faculty of Medicine, Department of Physical Medicine and Rehabilitation, for osteoporosis examination were analyzed. BMDs of the lumbar spine and femoral sites were measured. Patient and control groups were established based on their T-score values being above and/or below -1. After venous blood sampling, C421T and C575T polymorphisms of the RANK gene were assessed through PCR process following DNA extraction. Genotype frequencies for the C421T and C575T polymorphisms were compared between the control group and the patient group. No significant difference was detected between the two groups for both polymorphisms. There was also no significant difference between the control and patient groups in terms of the combined genotype (p = 0.752) and the combined haplotype analysis of the C421T and C575T polymorphisms (p = 0.723). In the control and patient groups separately, no significant differences in BMD values either at the femoral sites or at the lumbar spine were detected between the combined genotypes of the two polymorphisms. The genotypes, combined genotypes and allele frequencies of C421T and C575T polymorphisms of the RANK gene have not been found to be associated with BMD in Turkish women. Further studies including both sexes and more cases are required.
Analysis of DNA methylation in Arabidopsis thaliana based on methylation-sensitive AFLP markers.
Cervera, M T; Ruiz-García, L; Martínez-Zapater, J M
2002-12-01
AFLP analysis using restriction enzyme isoschizomers that differ in their sensitivity to methylation of their recognition sites has been used to analyse the methylation state of anonymous CCGG sequences in Arabidopsis thaliana. The technique was modified to improve the quality of fingerprints and to visualise larger numbers of scorable fragments. Sequencing of amplified fragments indicated that detection was generally associated with non-methylation of the cytosine to which the isoschizomer is sensitive. Comparison of EcoRI/ HpaII and EcoRI/ MspI patterns in different ecotypes revealed that 35-43% of CCGG sites were differentially digested by the isoschizomers. Interestingly, the pattern of digestion among different plants belonging to the same ecotype is highly conserved, with the rate of intra-ecotype methylation-sensitive polymorphisms being less than 1%. However, pairwise comparisons of methylation patterns between samples belonging to different ecotypes revealed differences in up to 34% of the methylation-sensitive polymorphisms. The lack of correlation between inter-ecotype similarity matrices based on methylation-insensitive or methylation-sensitive polymorphisms suggests that whatever the mechanisms regulating methylation may be, they are not related to nucleotide sequence variation.
Turner, Peter C; Yomano, Lorraine P; Jarboe, Laura R; York, Sean W; Baggett, Christy L; Moritz, Brélan E; Zentz, Emily B; Shanmugam, K T; Ingram, Lonnie O
2012-04-01
Escherichia coli KO11 (ATCC 55124) was engineered in 1990 to produce ethanol by chromosomal insertion of the Zymomonas mobilis pdc and adhB genes into E. coli W (ATCC 9637). KO11FL, our current laboratory version of KO11, and its parent E. coli W were sequenced, and contigs assembled into genomic sequences using optical NcoI restriction maps as templates. E. coli W contained plasmids pRK1 (102.5 kb) and pRK2 (5.4 kb), but KO11FL only contained pRK2. KO11FL optical maps made with AflII and with BamHI showed a tandem repeat region, consisting of at least 20 copies of a 10-kb unit. The repeat region was located at the insertion site for the pdc, adhB, and chloramphenicol-resistance genes. Sequence coverage of these genes was about 25-fold higher than average, consistent with amplification of the foreign genes that were inserted as circularized DNA. Selection for higher levels of chloramphenicol resistance originally produced strains with higher pdc and adhB expression, and hence improved fermentation performance, by increasing the gene copy number. Sequence data for an earlier version of KO11, ATCC 55124, indicated that multiple copies of pdc adhB were present. Comparison of the W and KO11FL genomes showed large inversions and deletions in KO11FL, mostly enabled by IS10, which is absent from W but present at 30 sites in KO11FL. The early KO11 strain ATCC 55124 had no rearrangements, contained only one IS10, and lacked most accumulated single nucleotide polymorphisms (SNPs) present in KO11FL. Despite rearrangements and SNPs in KO11FL, fermentation performance was equal to that of ATCC 55124.
Hunt, Patrick; Rehm, Oliver; Weiler, Andreas
2006-12-01
Using soft tissue grafts for anterior cruciate ligament (ACL) reconstruction, insertion site healing plays a crucial role in the long-term fate of the graft. It has been shown in an experimental animal study that using a soft tissue graft and anatomic graft fixation, a direct ligamentous insertion alike the native ACL developed 24 weeks postoperatively. Yet there are no reports on the long-term insertion site healing of anatomically fixed soft tissue grafts. The objective of this study was to evaluate graft insertion site healing, the intra-tunnel fate of the graft and its osseous replacement 2 years after ACL reconstruction in sheep. The left ACLs of six sheep were replaced by an autologous flexor tendon split graft and anatomically fixed with biodegradable poly-(D, L-lactide) interference screws. Animals received polychromic sequential labeling at different points in time to determine bone apposition per period. For evaluation of the insertion site healing and intra-tunnel changes, MRI scans were taken in vivo. Following sacrifice, radiographic imaging, conventional histology and fluorescence microscopy was undertaken. Most of the specimens showed a wide direct ligamentous insertion. It showed patterns alike the direct ligament insertion seen in intact ACLs. The intra-tunnel part of the graft had completely lost its tendon-like structure and in two cases, it was separated from the graft insertion by a thick bony layer. The biodegradable interference screw was fully degraded in all specimens. Ossification of the former drill tunnels was intense, showing only partial-length tunnel remnants in one femoral and three tibial specimens. As the graft heals to the joint surface and the aperture site is closed with soft tissue, mechanical stress of the intra-tunnel part of the graft is eliminated and the bone tunnel is protected from synovial fluid, resulting in osseous bridging of the tunnel aperture site, accelerated intra-tunnel graft resorption and its osseous replacement.
Sanseverino, Walter; Hénaff, Elizabeth; Vives, Cristina; Pinosio, Sara; Burgos-Paz, William; Morgante, Michele; Ramos-Onsins, Sebastián E; Garcia-Mas, Jordi; Casacuberta, Josep Maria
2015-10-01
The availability of extensive databases of crop genome sequences should allow analysis of crop variability at an unprecedented scale, which should have an important impact in plant breeding. However, up to now the analysis of genetic variability at the whole-genome scale has been mainly restricted to single nucleotide polymorphisms (SNPs). This is a strong limitation as structural variation (SV) and transposon insertion polymorphisms are frequent in plant species and have had an important mutational role in crop domestication and breeding. Here, we present the first comprehensive analysis of melon genetic diversity, which includes a detailed analysis of SNPs, SV, and transposon insertion polymorphisms. The variability found among seven melon varieties representing the species diversity and including wild accessions and highly breed lines, is relatively high due in part to the marked divergence of some lineages. The diversity is distributed nonuniformly across the genome, being lower at the extremes of the chromosomes and higher in the pericentromeric regions, which is compatible with the effect of purifying selection and recombination forces over functional regions. Additionally, this variability is greatly reduced among elite varieties, probably due to selection during breeding. We have found some chromosomal regions showing a high differentiation of the elite varieties versus the rest, which could be considered as strongly selected candidate regions. Our data also suggest that transposons and SV may be at the origin of an important fraction of the variability in melon, which highlights the importance of analyzing all types of genetic variability to understand crop genome evolution. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Hammad, A; Yahia, S; Laimon, W; Hamed, S M; Shouma, A; Shalaby, N M; Abdel-Hady, D; Ghanem, R; El-Farahaty, R M; El-Bassiony, S R; Hammad, E M
2017-06-01
Introduction Angiotensin-converting enzyme (ACE) is crucial in the pathogenesis of systemic lupus erythematosus through angiotensin II which regulates vascular tone and endothelial functions. Objectives To study the frequency of ACE insertion/deletion (I/D) gene polymorphism in Egyptian children with systemic lupus erythematosus and its possible relation to the renal pathology in cases with lupus nephritis. Subjects and methods The frequency of ACE gene insertion/deletion polymorphism genotypes was determined in 78 Egyptian children with systemic lupus erythematosus and compared to a matched group of 140 healthy controls using polymerase chain reaction. Results The DD genotype of the ACE gene was higher in systemic lupus erythematosus patients when compared to controls ( P<0.0001; odds ratio (OR) 2.4; 95% confidence interval (CI) 1.7-3.3) and the D allele was more frequent than the I allele in systemic lupus erythematosus patients in comparison to controls ( P < 0.0001; OR = 2.2; 95% CI = (1.6-3.1). In the lupus nephritis group, the DD genotype was significantly higher in those with proliferative lupus nephritis when compared to those with non-proliferative lupus nephritis ( P = 0.02; OR = 1.45; 95% CI = 1.4-1.6). Also, patients with proliferative lupus nephritis showed a higher frequency of the D allele ( P < 0.001; OR = 1.98; 95% CI = 1.3-2.9). Conclusion The D allele and DD genotype of the ACE gene appear to be a risk factor for the susceptibility of systemic lupus erythematosus and occurrence of proliferative nephritis in Egyptian children.
Yadav, Suresh Kumar; Singh, Sudhir; Gupta, Shalini; Brahma Bhatt, Madan Lal; Mishra, Durga P; Roy, D; Sanyal, Somali
2018-01-01
Genetic variations in nucleotide excision repair genes can alter the risk of squamous cell carcinoma of head and neck (SCCHN). The present study has genotyped 334 subjects from North Indian population for xeroderma pigmentosum complementation Group C (XPC) rs2228001A>C, XPC rs77907221 polyadenylate (PAT) deletion/insertion (D/I), xeroderma pigmentosum complementation Group D - rs13181A>C, and xeroderma pigmentosum complementation Type G rs17655 G>C polymorphisms with polymerase chain reaction (PCR)-restriction-fragment length polymorphism or allele-specific PCR methods. Compared to D allele, I allele for XPC PAT D/I polymorphism was associated with significantly decreased the risk of SCCHN (odds ratios = 0.67, 95% confidence interval [CI] =0.48-0.94, P = 0.03). Haplotype CI constituted from XPC polymorphisms was also associated with decreased risk of SCCHN (P = 0.004). In contrast, haplotype Crohn's disease significantly increased the risk for SCCHN (P < 0.00). A significant early onset of SCCHN was observed in individuals with CC genotype for XPC A>C polymorphism (P = 0.004). Our results suggest a possible risk modulation for SCCHN with XPC polymorphisms in North Indian population.
Detecting a hierarchical genetic population structure via Multi-InDel markers on the X chromosome
Fan, Guang Yao; Ye, Yi; Hou, Yi Ping
2016-01-01
Detecting population structure and estimating individual biogeographical ancestry are very important in population genetics studies, biomedical research and forensics. Single-nucleotide polymorphism (SNP) has long been considered to be a primary ancestry-informative marker (AIM), but it is constrained by complex and time-consuming genotyping protocols. Following up on our previous study, we propose that a multi-insertion-deletion polymorphism (Multi-InDel) with multiple haplotypes can be useful in ancestry inference and hierarchical genetic population structures. A validation study for the X chromosome Multi-InDel marker (X-Multi-InDel) as a novel AIM was conducted. Genetic polymorphisms and genetic distances among three Chinese populations and 14 worldwide populations obtained from the 1000 Genomes database were analyzed. A Bayesian clustering method (STRUCTURE) was used to discern the continental origins of Europe, East Asia, and Africa. A minimal panel of ten X-Multi-InDels was verified to be sufficient to distinguish human ancestries from three major continental regions with nearly the same efficiency of the earlier panel with 21 insertion-deletion AIMs. Along with the development of more X-Multi-InDels, an approach using this novel marker has the potential for broad applicability as a cost-effective tool toward more accurate determinations of individual biogeographical ancestry and population stratification. PMID:27535707
Sima, Xiutian; Xu, Jianguo; Li, Jin; You, Chao
2013-08-01
Growing evidence indicates that vascular inflammation is a common phenomenon in the pathogenesis of intracranial aneurysms (IAs). Nuclear factor kappa B is a key molecule that is involved in the vascular inflammation of IA. We hypothesized that an insertion/deletion (ins/del) ATTG polymorphism located between two putative key promoter regulatory elements in the NFKB1 gene may be related to the risk of IA. We performed a case-control study, including 164 patients with IA and 525 healthy controls in a Chinese population using a polymerase chain reaction-polyacrylamide gel electrophoresis assay. A significantly decreased risk of IA was observed in the ATTG1/ATTG2 and ATTG2/ATTG2 genotypes compared with the ATTG1/ATTG1 genotype (ATTG1/ATTG2 vs. ATTG1/ATTG1: odds ratio [OR]=0.58, 95% confidence interval [95% CI]=0.39-0.87, p=0.007; ATTG2/ATTG2 vs. ATTG1/ATTG1: OR=0.12, 95% CI=0.06-0.23, p<0.001), and also the ATTG2 allele (ATTG2 vs. ATTG1: OR=0.41, 95% CI=0.32-0.54, p<0.001). These findings suggest that the NFKB1 -94ins/del ATTG polymorphism may contribute to the risk of IA.
Large exon size does not limit splicing in vivo.
Chen, I T; Chasin, L A
1994-03-01
Exon sizes in vertebrate genes are, with a few exceptions, limited to less than 300 bases. It has been proposed that this limitation may derive from the exon definition model of splice site recognition. In this model, a downstream donor site enhances splicing at the upstream acceptor site of the same exon. This enhancement may require contact between factors bound to each end of the exon; an exon size limitation would promote such contact. To test the idea that proximity was required for exon definition, we inserted random DNA fragments from Escherichia coli into a central exon in a three-exon dihydrofolate reductase minigene and tested whether the expanded exons were efficiently spliced. DNA from a plasmid library of expanded minigenes was used to transfect a CHO cell deletion mutant lacking the dhfr locus. PCR analysis of DNA isolated from the pooled stable cotransfectant populations displayed a range of DNA insert sizes from 50 to 1,500 nucleotides. A parallel analysis of the RNA from this population by reverse transcription followed by PCR showed a similar size distribution. Central exons as large as 1,400 bases could be spliced into mRNA. We also tested individual plasmid clones containing exon inserts of defined sizes. The largest exon included in mRNA was 1,200 bases in length, well above the 300-base limit implied by the survey of naturally occurring exons. We conclude that a limitation in exon size is not part of the exon definition mechanism.
Characterization of a new high copy Stowaway family MITE, BRAMI-1 in Brassica genome
2013-01-01
Background Miniature inverted-repeat transposable elements (MITEs) are expected to play important roles in evolution of genes and genome in plants, especially in the highly duplicated plant genomes. Various MITE families and their roles in plants have been characterized. However, there have been fewer studies of MITE families and their potential roles in evolution of the recently triplicated Brassica genome. Results We identified a new MITE family, BRAMI-1, belonging to the Stowaway super-family in the Brassica genome. In silico mapping revealed that 697 members are dispersed throughout the euchromatic regions of the B. rapa pseudo-chromosomes. Among them, 548 members (78.6%) are located in gene-rich regions, less than 3 kb from genes. In addition, we identified 516 and 15 members in the 470 Mb and 15 Mb genomic shotgun sequences currently available for B. oleracea and B. napus, respectively. The resulting estimated copy numbers for the entire genomes were 1440, 1464 and 2490 in B. rapa, B. oleracea and B. napus, respectively. Concurrently, only 70 members of the related Arabidopsis ATTIRTA-1 MITE family were identified in the Arabidopsis genome. Phylogenetic analysis revealed that BRAMI-1 elements proliferated in the Brassica genus after divergence from the Arabidopsis lineage. MITE insertion polymorphism (MIP) was inspected for 50 BRAMI-1 members, revealing high levels of insertion polymorphism between and within species of Brassica that clarify BRAMI-1 activation periods up to the present. Comparative analysis of the 71 genes harbouring the BRAMI-1 elements with their non-insertion paralogs (NIPs) showed that the BRAMI-1 insertions mainly reside in non-coding sequences and that the expression levels of genes with the elements differ from those of their NIPs. Conclusion A Stowaway family MITE, named as BRAMI-1, was gradually amplified and remained present in over than 1400 copies in each of three Brassica species. Overall, 78% of the members were identified in gene-rich regions, and it is assumed that they may contribute to the evolution of duplicated genes in the highly duplicated Brassica genome. The resulting MIPs can serve as a good source of DNA markers for Brassica crops because the insertions are highly dispersed in the gene-rich euchromatin region and are polymorphic between or within species. PMID:23547712
Trujillano, D; Ramos, M D; González, J; Tornador, C; Sotillo, F; Escaramis, G; Ossowski, S; Armengol, L; Casals, T; Estivill, X
2013-07-01
Here we have developed a novel and much more efficient strategy for the complete molecular characterisation of the cystic fibrosis (CF) transmembrane regulator (CFTR) gene, based on multiplexed targeted resequencing. We have tested this approach in a cohort of 92 samples with previously characterised CFTR mutations and polymorphisms. After enrichment of the pooled barcoded DNA libraries with a custom NimbleGen SeqCap EZ Choice array (Roche) and sequencing with a HiSeq2000 (Illumina) sequencer, we applied several bioinformatics tools to call mutations and polymorphisms in CFTR. The combination of several bioinformatics tools allowed us to detect all known pathogenic variants (point mutations, short insertions/deletions, and large genomic rearrangements) and polymorphisms (including the poly-T and poly-thymidine-guanine polymorphic tracts) in the 92 samples. In addition, we report the precise characterisation of the breakpoints of seven genomic rearrangements in CFTR, including those of a novel deletion of exon 22 and a complex 85 kb inversion which includes two large deletions affecting exons 4-8 and 12-21, respectively. This work is a proof-of-principle that targeted resequencing is an accurate and cost-effective approach for the genetic testing of CF and CFTR-related disorders (ie, male infertility) amenable to the routine clinical practice, and ready to substitute classical molecular methods in medical genetics.
Howard, Timothy D.; Giles, Wayne H.; Xu, Jianfeng; Wozniak, Marcella A.; Malarcher, Ann M.; Lange, Leslie A.; Macko, Richard F.; Basehore, Monica J.; Meyers, Deborah A.; Cole, John W.; Kittner, Steven J.
2006-01-01
Background and Purpose Endothelial nitric oxide exerts a variety of protective effects on endothelial cells and blood vessels, and therefore the nitric oxide synthase 3 gene (NOS3) is a logical candidate gene for stroke susceptibility. Methods We used the population-based Stroke Prevention in Young Women case-control study to assess the association of five NOS3 polymorphisms in 110 cases (46% black) with ischemic stroke and 206 controls (38% black), 15 to 44 years of age. Polymorphisms included 3 single nucleotide polymorphisms (SNPs) in the promoter region (−1468 T>A, −922 G>A, −786 T>C), 1 SNP in exon 7 (G894T), and 1 insertion/deletion polymorphism within intron 4. Results Significant associations with both the −922 G>A and −786 T>C SNPs with ischemic stroke were observed in the black, but not the white, population. This association was attributable to an increased prevalence of the −922 A allele (OR=3.0, 95% CI=1.3 to 6.8; P=0.005) and the −786 T allele (OR=2.9, 95% CI=1.3 to 6.4; P=0.005) in cases versus controls. These 2 SNPs were in strong linkage disequilibrium (D′=1.0), making it impossible to determine, within the confines of this genetic study, whether 1 or both of these polymorphisms are functionally related to NOS3 expression. Two sets of haplotypes were also identified, 1 of which may confer an increased susceptibility to stroke in blacks, whereas the other appears to be protective. Conclusion Promoter variants in NOS3 may be associated with ischemic stroke susceptibility among young black women. PMID:16100023
Howard, Timothy D; Giles, Wayne H; Xu, Jianfeng; Wozniak, Marcella A; Malarcher, Ann M; Lange, Leslie A; Macko, Richard F; Basehore, Monica J; Meyers, Deborah A; Cole, John W; Kittner, Steven J
2005-09-01
Endothelial nitric oxide exerts a variety of protective effects on endothelial cells and blood vessels, and therefore the nitric oxide synthase 3 gene (NOS3) is a logical candidate gene for stroke susceptibility. We used the population-based Stroke Prevention in Young Women case-control study to assess the association of five NOS3 polymorphisms in 110 cases (46% black) with ischemic stroke and 206 controls (38% black), 15 to 44 years of age. Polymorphisms included 3 single nucleotide polymorphisms (SNPs) in the promoter region (-1468 T>A, -922 G>A, -786 T>C), 1 SNP in exon 7 (G894T), and 1 insertion/deletion polymorphism within intron 4. Significant associations with both the -922 G>A and -786 T>C SNPs with ischemic stroke were observed in the black, but not the white, population. This association was attributable to an increased prevalence of the -922 A allele (OR=3.0, 95% CI=1.3 to 6.8; P=0.005) and the -786 T allele (OR=2.9, 95% CI=1.3 to 6.4; P=0.005) in cases versus controls. These 2 SNPs were in strong linkage disequilibrium (D'=1.0), making it impossible to determine, within the confines of this genetic study, whether 1 or both of these polymorphisms are functionally related to NOS3 expression. Two sets of haplotypes were also identified, 1 of which may confer an increased susceptibility to stroke in blacks, whereas the other appears to be protective. Promoter variants in NOS3 may be associated with ischemic stroke susceptibility among young black women.
Role of selected polymorphisms in determining muscle fiber composition in Japanese men and women.
Kumagai, Hiroshi; Tobina, Takuro; Ichinoseki-Sekine, Noriko; Kakigi, Ryo; Tsuzuki, Takamasa; Zempo, Hirofumi; Shiose, Keisuke; Yoshimura, Eiichi; Kumahara, Hideaki; Ayabe, Makoto; Higaki, Yasuki; Yamada, Ryo; Kobayashi, Hiroyuki; Kiyonaga, Akira; Naito, Hisashi; Tanaka, Hiroaki; Fuku, Noriyuki
2018-05-01
Genetic polymorphisms and sex differences are suggested to affect muscle fiber composition; however, no study has investigated the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences. Therefore, the present study examined the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences in the Japanese population. The present study included 211 healthy Japanese individuals (102 men and 109 women). Muscle biopsies were obtained from the vastus lateralis to determine the proportion of myosin heavy chain (MHC) isoforms (MHC-I, MHC-IIa, and MHC-IIx). Moreover, we analyzed polymorphisms in α-actinin-3 gene ( ACTN3; rs1815739 ), angiotensin-converting enzyme gene ( ACE; rs4341 ), hypoxia-inducible factor 1 α gene ( rs11549465 ), vascular endothelial growth factor receptor 2 gene ( rs1870377 ), and angiotensin II receptor, type 2 gene ( rs11091046 ), by TaqMan single-nucleotide polymorphism genotyping assays. The proportion of MHC-I was 9.8% lower in men than in women, whereas the proportion of MHC-IIa and MHC-IIx was higher in men than in women (5.0 and 4.6%, respectively). Men with the ACTN3 RR + RX genotype had a 4.8% higher proportion of MHC-IIx than those with the ACTN3 XX genotype. Moreover, men with the ACE ID + DD genotype had a 4.7% higher proportion of MHC-I than those with the ACE II genotype. Furthermore, a combined genotype of ACTN3 R577X and ACE insertion/deletion (I/D) was significantly correlated with the proportion of MHC-I ( r = -0.23) and MHC-IIx ( r = 0.27) in men. In contrast, no significant correlation was observed between the examined polymorphisms and muscle fiber composition in women. These results suggest that the ACTN3 R577X and ACE I/D polymorphisms independently affect the proportion of human skeletal muscle fibers MHC-I and MHC-IIx in men but not in women. NEW & NOTEWORTHY In men, the RR + RX genotype of the α-actinin-3 gene ( ACTN3) R577X polymorphism was associated with a higher proportion of myosin heavy chain (MHC)-IIx. The ID + DD genotype of the angiotensin-converting enzyme gene ( ACE) insertion/deletion (I/D) polymorphism, in contrast to a previous finding, was associated with a higher proportion of MHC-I in men. In addition, the combined genotype of these polymorphisms was correlated with the proportion of MHC-I and MHC-IIx in men. Thus ACTN3 R577X and ACE I/D polymorphisms influence the muscle fiber composition in Japanese men.
Distefano, Gaetano; Caruso, Marco; La Malfa, Stefano; Gentile, Alessandra; Wu, Shu-Biao
2012-01-01
High resolution melting curve analysis (HRM) has been used as an efficient, accurate and cost-effective tool to detect single nucleotide polymorphisms (SNPs) or insertions or deletions (INDELs). However, its efficiency, accuracy and applicability to discriminate microsatellite polymorphism have not been extensively assessed. The traditional protocols used for SSR genotyping include PCR amplification of the DNA fragment and the separation of the fragments on electrophoresis-based platform. However, post-PCR handling processes are laborious and costly. Furthermore, SNPs present in the sequences flanking repeat motif cannot be detected by polyacrylamide-gel-electrophoresis based methods. In the present study, we compared the discriminating power of HRM with the traditional electrophoresis-based methods and provided a panel of primers for HRM genotyping in Citrus. The results showed that sixteen SSR markers produced distinct polymorphic melting curves among the Citrus spp investigated through HRM analysis. Among those, 10 showed more genotypes by HRM analysis than capillary electrophoresis owing to the presence of SNPs in the amplicons. For the SSR markers without SNPs present in the flanking region, HRM also gave distinct melting curves which detected same genotypes as were shown in capillary electrophoresis (CE) analysis. Moreover, HRM analysis allowed the discrimination of most of the 15 citrus genotypes and the resulting genetic distance analysis clustered them into three main branches. In conclusion, it has been approved that HRM is not only an efficient and cost-effective alternative of electrophoresis-based method for SSR markers, but also a method to uncover more polymorphisms contributed by SNPs present in SSRs. It was therefore suggested that the panel of SSR markers could be used in a variety of applications in the citrus biodiversity and breeding programs using HRM analysis. Furthermore, we speculate that the HRM analysis can be employed to analyse SSR markers in a wide range of applications in all other species.
Shao, Wei; Shan, Jigui; Kearney, Mary F; Wu, Xiaolin; Maldarelli, Frank; Mellors, John W; Luke, Brian; Coffin, John M; Hughes, Stephen H
2016-07-04
The NCI Retrovirus Integration Database is a MySql-based relational database created for storing and retrieving comprehensive information about retroviral integration sites, primarily, but not exclusively, HIV-1. The database is accessible to the public for submission or extraction of data originating from experiments aimed at collecting information related to retroviral integration sites including: the site of integration into the host genome, the virus family and subtype, the origin of the sample, gene exons/introns associated with integration, and proviral orientation. Information about the references from which the data were collected is also stored in the database. Tools are built into the website that can be used to map the integration sites to UCSC genome browser, to plot the integration site patterns on a chromosome, and to display provirus LTRs in their inserted genome sequence. The website is robust, user friendly, and allows users to query the database and analyze the data dynamically. https://rid.ncifcrf.gov ; or http://home.ncifcrf.gov/hivdrp/resources.htm .
Genetic and DNA sequence analysis of the kanamycin resistance transposon Tn903.
Grindley, N D; Joyce, C M
1980-01-01
The kanamycin resistance transposon Tn903 consists of a unique region of about 1000 base pairs bounded by a pair of 1050-base-pair inverted repeat sequences. Each repeat contains two Pvu II endonuclease cleavage sites separated by 520 base pairs. We have constructed derivatives of Tn903 in which this 520-base-pair fragment is deleted from one or both repeats. Those derivatives that lack both 520-base-pair fragments cannot transpose, whereas those that lack just one remain transposition proficient. One such transposable derivative, Tn903 delta I, has been selected for further study. We have determined the sequence of the intact inverted repeat. The 18 base pairs at each end are identical and inverted relative to one another, a structure characteristic of insertion sequences. Additional experiments indicate that a single inverted repeat from Tn903 can, in fact, transpose; we propose that this element be called IS903. To correlate the DNA sequence with genetic activities, we have created mutations by inserting a 10-base-pair DNA fragment at several sites within the intact repeat of Tn903 delta 1, and we have examined the effect of such insertions on transposability. The results suggest that IS903 encodes a 307-amino-acid polypeptide (a "transposase") that is absolutely required for transposition of IS903 or Tn903. Images PMID:6261245
Pelet, T; Curran, J; Kolakofsky, D
1991-01-01
The P gene of bovine parainfluenza virus 3 (bPIV3) contains two downstream overlapping ORFs, called V and D. By comparison with the mRNA editing sites of other paramyxoviruses, two editing sites were predicted for bPIV3; site a to express the D protein, and site b to express the V protein. Examination of the bPIV3 mRNAs, however, indicates that site b is non-functional whereas site a operates frequently. Insertions at site a give rise to both V and D protein mRNAs, because a very broad distribution of Gs is added when insertions occur. This broad distribution is very different from the editing sites of Sendai virus or SV5, where predominantly one form of edited mRNA containing either a one or two G insertion respectively is created, to access the single overlapping ORF of these viruses. A model is proposed to explain how paramyxoviruses control the range of G insertions on that fraction of the mRNAs where insertions occur. The bPIV3 P gene is unique as far as we know, in that a sizeable portion of the gene expresses all 3 reading frames as protein. bPIV3 apparently does this from a single editing site by removing the constraints which control the number of slippage rounds which take place. Images PMID:1846805
Effective screen of CRISPR/Cas9-induced mutants in rice by single-strand conformation polymorphism.
Zheng, Xuelian; Yang, Shixin; Zhang, Dengwei; Zhong, Zhaohui; Tang, Xu; Deng, Kejun; Zhou, Jianping; Qi, Yiping; Zhang, Yong
2016-07-01
A method based on DNA single-strand conformation polymorphism is demonstrated for effective genotyping of CRISPR/Cas9-induced mutants in rice. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) has been widely adopted for genome editing in many organisms. A large proportion of mutations generated by CRISPR/Cas9 are very small insertions and deletions (indels), presumably because Cas9 generates blunt-ended double-strand breaks which are subsequently repaired without extensive end-processing. CRISPR/Cas9 is highly effective for targeted mutagenesis in the important crop, rice. For example, homozygous mutant seedlings are commonly recovered from CRISPR/Cas9-treated calli. However, many current mutation detection methods are not very suitable for screening homozygous mutants that typically carry small indels. In this study, we tested a mutation detection method based on single-strand conformational polymorphism (SSCP). We found it can effectively detect small indels in pilot experiments. By applying the SSCP method for CRISRP-Cas9-mediated targeted mutagenesis in rice, we successfully identified multiple mutants of OsROC5 and OsDEP1. In conclusion, the SSCP analysis will be a useful genotyping method for rapid identification of CRISPR/Cas9-induced mutants, including the most desirable homozygous mutants. The method also has high potential for similar applications in other plant species.
Chmait, Ramen H; Chon, Andrew H; Korst, Lisa M; Llanes, Arlyn; Kontopoulos, Eftichia V; Quintero, Ruben A
2018-07-01
The objective of this study was to assess whether the location of the trocar insertion site for laser treatment of twin-twin transfusion syndrome was associated with preterm-premature rupture of membranes (PPROM) and preterm birth (PTB). In this study trocar location was documented in the operating room. Lower uterine segment (LUS) location was defined as any insertion <10 cm vertically from the pubic symphysis. Lateral location was defined as ≥5 cm horizontally from the midline. Patient characteristics were tested against three outcomes: PPROM ≤ 21 days postoperative, PTB < 28 weeks, and PTB < 32 weeks. For each outcome, multiple logistic models were fitted to examine the effect of trocar location, controlling for potential risk factors. A total of 743 patients were studied. Patients with LUS location were twice as likely as those with a more superior location to have PPROM ≤ 21 days (OR = 2.33, 1.12-4.83, p = 0.0236). Patients with both a LUS and Lateral location were over six times more likely to have PPROM ≤ 21 days (OR = 6.66, 2.36-18.78, p = 0.0003). Trocar insertion site was not associated with PTB. We found that trocar insertion in the LUS, particularly the lateral LUS, was associated with an increased risk of PPROM. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Zeron-Medina, Jorge; Wang, Xuting; Repapi, Emmanouela; Campbell, Michelle R.; Su, Dan; Castro-Giner, Francesc; Davies, Benjamin; Peterse, Elisabeth F.P.; Sacilotto, Natalia; Walker, Graeme J.; Terzian, Tamara; Tomlinson, Ian P.; Box, Neil F.; Meinshausen, Nicolai; De Val, Sarah; Bell, Douglas A.; Bond, Gareth L.
2014-01-01
SUMMARY The ability of p53 to regulate transcription is crucial for tumor suppression and implies that inherited polymorphisms in functional p53-binding sites could influence cancer. Here, we identify a polymorphic p53 responsive element and demonstrate its influence on cancer risk using genome-wide data sets of cancer susceptibility loci, genetic variation, p53 occupancy, and p53-binding sites. We uncover a single-nucleotide polymorphism (SNP) in a functional p53-binding site and establish its influence on the ability of p53 to bind to and regulate transcription of the KITLG gene. The SNP resides in KITLG and associates with one of the largest risks identified among cancer genome-wide association studies. We establish that the SNP has undergone positive selection throughout evolution, signifying a selective benefit, but go on to show that similar SNPs are rare in the genome due to negative selection, indicating that polymorphisms in p53-binding sites are primarily detrimental to humans. PMID:24120139
Madampage, Claudia Avis; Rawlyk, Neil; Crockford, Gordon; Van Donkersgoed, Joyce; Dorin, Craig; Potter, Andrew
2015-07-01
Histophilus somni, a causative agent of the bovine respiratory disease complex, can also cause a variety of systemic disorders, including bronchopneumonia, myocarditis, pericarditis, arthritis, pleuritis, and infectious thrombotic meningoencephalitis. The purpose of this study was to determine if currently circulating strains differ from those of the 1980s by identifying genomic changes. Single nucleotide polymorphisms (SNPs) and insertion and deletion (INDEL) sites were examined by whole-genome sequencing in 12 samples, 6 old and 6 new. The 31 028 SNP/INDELs recorded were compared against the reference genome sequence of the pathogenic H. somni strain 2336. The distribution of about 75% of these SNPs within a specified gene differed between old and new isolates and did not follow any particular pattern. The other 25% clustered into 2 groups containing the same SNPs in various genes: group I included 5 old isolates and 1 new isolate; group II included 5 new isolates and 1 old isolate. For putative virulence genes there were more SNPs in group I compared with strain 2336, itself an older isolate, than in group II. Although only 25% of all the SNPs formed 2 clusters, the results suggest some genetic difference in various genes between old and new strains.
Madampage, Claudia Avis; Rawlyk, Neil; Crockford, Gordon; Van Donkersgoed, Joyce; Dorin, Craig; Potter, Andrew
2015-01-01
Histophilus somni, a causative agent of the bovine respiratory disease complex, can also cause a variety of systemic disorders, including bronchopneumonia, myocarditis, pericarditis, arthritis, pleuritis, and infectious thrombotic meningoencephalitis. The purpose of this study was to determine if currently circulating strains differ from those of the 1980s by identifying genomic changes. Single nucleotide polymorphisms (SNPs) and insertion and deletion (INDEL) sites were examined by whole-genome sequencing in 12 samples, 6 old and 6 new. The 31 028 SNP/INDELs recorded were compared against the reference genome sequence of the pathogenic H. somni strain 2336. The distribution of about 75% of these SNPs within a specified gene differed between old and new isolates and did not follow any particular pattern. The other 25% clustered into 2 groups containing the same SNPs in various genes: group I included 5 old isolates and 1 new isolate; group II included 5 new isolates and 1 old isolate. For putative virulence genes there were more SNPs in group I compared with strain 2336, itself an older isolate, than in group II. Although only 25% of all the SNPs formed 2 clusters, the results suggest some genetic difference in various genes between old and new strains. PMID:26130851
Single tube genotyping of sickle cell anaemia using PCR-based SNP analysis.
Waterfall, C M; Cobb, B D
2001-12-01
Allele-specific amplification (ASA) is a generally applicable technique for the detection of known single nucleotide polymorphisms (SNPs), deletions, insertions and other sequence variations. Conventionally, two reactions are required to determine the zygosity of DNA in a two-allele system, along with significant upstream optimisation to define the specific test conditions. Here, we combine single tube bi-directional ASA with a 'matrix-based' optimisation strategy, speeding up the whole process in a reduced reaction set. We use sickle cell anaemia as our model SNP system, a genetic disease that is currently screened using ASA methods. Discriminatory conditions were rapidly optimised enabling the unambiguous identification of DNA from homozygous sickle cell patients (HbS/S), heterozygous carriers (HbA/S) or normal DNA in a single tube. Simple downstream mathematical analyses based on product yield across the optimisation set allow an insight into the important aspects of priming competition and component interactions in this competitive PCR. This strategy can be applied to any polymorphism, defining specific conditions using a multifactorial approach. The inherent simplicity and low cost of this PCR-based method validates bi-directional ASA as an effective tool in future clinical screening and pharmacogenomic research where more expensive fluorescence-based approaches may not be desirable.
Heidari, Farzad; Vasudevan, Ramachandran; Mohd Ali, Siti Zubaidah; Ismail, Patimah; Etemad, Ali; Pishva, Seyyed Reza; Othman, Fauziah; Abu Bakar, Suhaili
2015-12-01
Several studies show that the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene has been associated with hypertension in various populations. The present study sought to determine the association of the I/D gene polymorphism among Malay male essential hypertensive subjects in response to ACE inhibitors (enalapril and lisinopril). A total of 72 patients with newly diagnosed hypertension and 72 healthy subjects were recruited in this study. Blood pressure was recorded from 0 to 24 weeks of treatment with enalapril or lisinopril. Genotyping of the I/D polymorphism was carried out using a standard PCR method. Statistically significant association of the D allele of the ACE gene was observed between the case and control subjects (p < 0.01). There was a decrease in blood pressure in the patients carrying the DD genotype (SBP=18.5±8.1 mmHg, DBP=15.29±7.1 mmHg) rather than the ID (SBP=4.1±3.3 mmHg, DBP=9.1±3.5 mmHg) and II genotypes (SBP= 3.0±0.2 mmHg, DBP 0.11±6.1 mmHg) of the ACE gene. Patients carrying the DD genotype had higher blood pressure-lowering response when treated with ACE inhibitors enalapril or lisinopril than those carrying ID and II genotypes, suggesting that the D allele may be a possible genetic marker for essential hypertension among Malay male subjects. © The Author(s) 2014.
Xu, Jing-Yuan; Zhu, Yan; Yi, Ze; Wu, Gang; Xie, Guo-Yong; Qin, Min-Jian
2018-01-01
"Wu zhu yu", which is obtained from the dried unripe fruits of Tetradium ruticarpum (A. Jussieu) T. G. Hartley, has been used as a traditional Chinese medicine for treatment of headaches, abdominal colic, and hypertension for thousands of years. The present study was designed to assess the molecular genetic diversity among 25 collected accessions of T. ruticarpum (Wu zhu yu in Chinese) from different areas of China, based on inter-primer binding site (iPBS) markers and inter-simple sequence repeat (ISSR) markers. Thirteen ISSR primers generated 151 amplification bands, of which 130 were polymorphic. Out of 165 bands that were amplified using 10 iPBS primers, 152 were polymorphic. The iPBS markers displayed a higher proportion of polymorphic loci (PPL = 92.5%) than the ISSR markers (PPL = 84.9%). The results showed that T. ruticarpum possessed high loci polymorphism and genetic differentiation occurred in this plant. The combined data of iPBS and ISSR markers scored on 25 accessions produced five clusters that approximately matched the geographic distribution of the species. The results indicated that both iPBS and ISSR markers were reliable and effective tools for analyzing the genetic diversity in T. ruticarpum. Copyright © 2018 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.
Sharma, Vishakha; Nandineni, Madhusudan R
2014-04-01
Potato (Solanum tuberosum) is an important non-cereal crop throughout the world and is highly recommended for ensuring global food security. Owing to the complexities in genetics and inheritance pattern of potato, the conventional method of cross breeding for developing improved varieties has been difficult. Identification and tagging of desirable traits with informative molecular markers would aid in the development of improved varieties. Insertional polymorphism of copia-like and gypsy-like long terminal repeat retrotransposons (RTN) were investigated among 47 potato varieties from India using Inter-Retrotransposon Amplified Polymorphism (IRAP) and Retrotransposon Microsatellite Amplified Polymorphism (REMAP) marker techniques and were compared with the DNA profiles obtained with simple sequence repeats (SSRs). The genetic polymorphism, efficiency of polymorphism and effectiveness of marker systems were evaluated to assess the extent of genetic diversity among Indian potato varieties. A total of 139 polymorphic SSR alleles, 270 IRAP and 98 REMAP polymorphic bands, showing polymorphism of 100%, 87.9% and 68.5%, respectively, were used for detailed characterization of the genetic relationships among potato varieties by using cluster analysis and principal coordinate analysis (PCoA). IRAP analysis resulted in the highest number of polymorphic bands with an average of 15 polymorphic bands per assay unit when compared to the other two marker systems. Based on pair-wise comparison, the genetic similarity was calculated using Dice similarity coefficient. The SSRs showed a wide range in genetic similarity values (0.485-0.971) as compared to IRAP (0.69-0.911) and REMAP (0.713-0.947). A Mantel's matrix correspondence test showed a high positive correlation (r=0.6) between IRAP and REMAP, an intermediate value (r=0.58) for IRAP and SSR and the lowest value (r=0.17) for SSR and REMAP. Statistically significant cophenetic correlation coefficient values, of 0.961, 0.941 and 0.905 were observed for REMAP, IRAP and SSR, respectively. The widespread presence and distinct DNA profiles for copia-like and gypsy-like RTNs in the examined genotypes indicate that these elements are active in the genome and may have even contributed to the potato genome organization. Although the three marker systems were capable of distinguishing all the 47 varieties; high reproducibility, low cost and ease of DNA profiling data collection make IRAP and REMAP markers highly efficient whole-genome scanning molecular probes for population genetic studies. Information obtained from the present study regarding the genetic association and distinctiveness provides an useful guide for selection of germplasm for plant breeding and conservation efforts. Copyright © 2014. Published by Elsevier Inc.
Identifying transposon insertions and their effects from RNA-sequencing data.
de Ruiter, Julian R; Kas, Sjors M; Schut, Eva; Adams, David J; Koudijs, Marco J; Wessels, Lodewyk F A; Jonkers, Jos
2017-07-07
Insertional mutagenesis using engineered transposons is a potent forward genetic screening technique used to identify cancer genes in mouse model systems. In the analysis of these screens, transposon insertion sites are typically identified by targeted DNA-sequencing and subsequently assigned to predicted target genes using heuristics. As such, these approaches provide no direct evidence that insertions actually affect their predicted targets or how transcripts of these genes are affected. To address this, we developed IM-Fusion, an approach that identifies insertion sites from gene-transposon fusions in standard single- and paired-end RNA-sequencing data. We demonstrate IM-Fusion on two separate transposon screens of 123 mammary tumors and 20 B-cell acute lymphoblastic leukemias, respectively. We show that IM-Fusion accurately identifies transposon insertions and their true target genes. Furthermore, by combining the identified insertion sites with expression quantification, we show that we can determine the effect of a transposon insertion on its target gene(s) and prioritize insertions that have a significant effect on expression. We expect that IM-Fusion will significantly enhance the accuracy of cancer gene discovery in forward genetic screens and provide initial insight into the biological effects of insertions on candidate cancer genes. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.
Mutation testing in Treacher Collins Syndrome.
Ellis, P E; Dawson, M; Dixon, M J
2002-12-01
To report on a study where 97 subjects were screened for mutations in the Treacher Collins syndrome (TCS) gene TCOF1. Ninety-seven subjects with a clinical diagnosis of TCS were screened for potential mutations in TCOF1, by means of single strand conformation polymorphism (SSCP) analysis. In those subjects where potential mutations were detected, sequence analysis was performed to determine the site and type of mutation present. Thirty-six TCS-specific mutations are reported including 27 deletions, six point mutations, two splice junction mutations, and one insertion/deletion. This brings the total number of mutations reported to date to 105. The importance of detection of these mutations is mainly in postnatal diagnosis and genetic counselling. Knowledge of the family specific mutation may also be used in prenatal diagnosis to confirm whether the foetus is affected or not, and give the parents the choice of whether to continue with the pregnancy.
Yoshihara, A; Tobina, T; Yamaga, T; Ayabe, M; Yoshitake, Y; Kimura, Y; Shimada, M; Nishimuta, M; Nakagawa, N; Ohashi, M; Hanada, N; Tanaka, H; Kiyonaga, A; Miyazaki, H
2009-01-01
The turning point in the deterioration of physical function seems to occur between the ages of 70 and 80 years. In particular, muscle strength may decline even more in subjects older than 75. A recent study found that the angiotensin-converting enzyme (ACE) genotype also affects physiological left ventricular hypertrophy. A very limited number of papers have examined genetic differences in resistance and endurance forms of a single sporting discipline. The purpose of this study was to evaluate the relationship between ACE genotype and physical function by controlling the known confounding factors including dental status. We selected 431 subjects who were aged 76 years and did not require special care for their daily activities. We conducted a medical examination, followed by 5 physical function tests, as follows: (1) maximum hand grip strength, (2) maximal isometric knee extensor strength, (3) maximal stepping rate for 10 s, (4) one-leg standing time with eyes open and (5) 10-meter maximum walking speed. Subjects were genotyped for the ACE intron 16 Alu insertion. In addition, serum concentrations of total cholesterol, total protein, IgA and IgG were measured at a commercial laboratory. The Eichner index was used as an indicator of occlusal condition. Multiple linear regression analysis was performed to evaluate the relationship between the ACE gene insertion/deletion (I/D) polymorphism and physical function considering confounding factors. The ACE gene I/D polymorphism was positively associated with hand grip strength and 10-meter maximum walking speed. Betas of hand grip strength were 0.09 for I/D (p = 0.022) and 0.12 for insertion/insertion (I/I; p = 0.004). Betas of 10-meter walking speed were -0.11 for I/D (p = 0.093) and -0.14 for I/I (p = 0.039). Dental status such as Eichner index class C was significantly associated with one-leg standing time with eyes open (beta -0.11; p = 0.028). This study suggests that there is a significant relationship between ACE genotype and physical function. In particular, subjects with the ACE deletion/deletion genotype were associated with upper extremities. Copyright 2009 S. Karger AG, Basel.
Defects in ion-implanted hcp-titanium: A first-principles study of electronic structures
NASA Astrophysics Data System (ADS)
Raji, Abdulrafiu T.; Mazzarello, Riccardo; Scandolo, Sandro; Nsengiyumva, Schadrack; Härting, Margit; Britton, David T.
2011-12-01
The electronic structures of hexagonal closed-packed (h.c.p) titanium containing a vacancy and krypton impurity atoms at various insertion sites are calculated by first-principles methods in the framework of the density-functional theory (DFT). The density of states (DOS) for titanium containing a vacancy defect shows resonance-like features. Also, the bulk electron density decreases from ˜0.15/Å 3 to ˜0.05/Å 3 at the vacancy centre. Electronic structure calculations have been performed to investigate what underlies the krypton site preference in titanium. The DOS of the nearest-neighbour (NN) titanium atoms to the octahedral krypton appears to be less distorted (relative to pure titanium) when compared to the NN titanium atoms to the tetrahedral krypton. The electronic density deformation maps show that polarization of the titanium atoms is stronger when the krypton atom is located at the tetrahedral site. Since krypton is a closed-shell atom, thus precluding any bonding with the titanium atoms, we may conclude that the polarization of the electrons in the vicinity of the inserted krypton atoms and the distortion of the DOS of the NN titanium atoms to the krypton serve to indicate which defect site is preferred when a krypton atom is inserted into titanium. Based on these considerations, we conclude that the substitutional site is the most favourable one, and the octahedral is the preferred interstitial site, in agreement with recent DFT calculations of the energetics of krypton impurity sites.
SINEs, evolution and genome structure in the opossum.
Gu, Wanjun; Ray, David A; Walker, Jerilyn A; Barnes, Erin W; Gentles, Andrew J; Samollow, Paul B; Jurka, Jerzy; Batzer, Mark A; Pollock, David D
2007-07-01
Short INterspersed Elements (SINEs) are non-autonomous retrotransposons, usually between 100 and 500 base pairs (bp) in length, which are ubiquitous components of eukaryotic genomes. Their activity, distribution, and evolution can be highly informative on genomic structure and evolutionary processes. To determine recent activity, we amplified more than one hundred SINE1 loci in a panel of 43 M. domestica individuals derived from five diverse geographic locations. The SINE1 family has expanded recently enough that many loci were polymorphic, and the SINE1 insertion-based genetic distances among populations reflected geographic distance. Genome-wide comparisons of SINE1 densities and GC content revealed that high SINE1 density is associated with high GC content in a few long and many short spans. Young SINE1s, whether fixed or polymorphic, showed an unbiased GC content preference for insertion, indicating that the GC preference accumulates over long time periods, possibly in periodic bursts. SINE1 evolution is thus broadly similar to human Alu evolution, although it has an independent origin. High GC content adjacent to SINE1s is strongly correlated with bias towards higher AT to GC substitutions and lower GC to AT substitutions. This is consistent with biased gene conversion, and also indicates that like chickens, but unlike eutherian mammals, GC content heterogeneity (isochore structure) is reinforced by substitution processes in the M. domestica genome. Nevertheless, both high and low GC content regions are apparently headed towards lower GC content equilibria, possibly due to a relative shift to lower recombination rates in the recent Monodelphis ancestral lineage. Like eutherians, metatherian (marsupial) mammals have evolved high CpG substitution rates, but this is apparently a convergence in process rather than a shared ancestral state.
Murukarthick, Jayakodi; Sampath, Perumal; Lee, Sang Choon; Choi, Beom-Soon; Senthil, Natesan; Liu, Shengyi; Yang, Tae-Jin
2014-06-20
MITE, TRIM and SINEs are miniature form transposable elements (mTEs) that are ubiquitous and dispersed throughout entire plant genomes. Tens of thousands of members cause insertion polymorphism at both the inter- and intra- species level. Therefore, mTEs are valuable targets and resources for development of markers that can be utilized for breeding, genetic diversity and genome evolution studies. Taking advantage of the completely sequenced genomes of Brassica rapa and B. oleracea, characterization of mTEs and building a curated database are prerequisite to extending their utilization for genomics and applied fields in Brassica crops. We have developed BrassicaTED as a unique web portal containing detailed characterization information for mTEs of Brassica species. At present, BrassicaTED has datasets for 41 mTE families, including 5894 and 6026 members from 20 MITE families, 1393 and 1639 members from 5 TRIM families, 1270 and 2364 members from 16 SINE families in B. rapa and B. oleracea, respectively. BrassicaTED offers different sections to browse structural and positional characteristics for every mTE family. In addition, we have added data on 289 MITE insertion polymorphisms from a survey of seven Brassica relatives. Genes with internal mTE insertions are shown with detailed gene annotation and microarray-based comparative gene expression data in comparison with their paralogs in the triplicated B. rapa genome. This database also includes a novel tool, K BLAST (Karyotype BLAST), for clear visualization of the locations for each member in the B. rapa and B. oleracea pseudo-genome sequences. BrassicaTED is a newly developed database of information regarding the characteristics and potential utility of mTEs including MITE, TRIM and SINEs in B. rapa and B. oleracea. The database will promote the development of desirable mTE-based markers, which can be utilized for genomics and breeding in Brassica species. BrassicaTED will be a valuable repository for scientists and breeders, promoting efficient research on Brassica species. BrassicaTED can be accessed at http://im-crop.snu.ac.kr/BrassicaTED/index.php.
Genetic and epigenetic variation in Spartina alterniflora following the Deepwater Horizon oil spill.
Robertson, Marta; Schrey, Aaron; Shayter, Ashley; Moss, Christina J; Richards, Christina
2017-09-01
Catastrophic events offer unique opportunities to study rapid population response to stress in natural settings. In concert with genetic variation, epigenetic mechanisms may allow populations to persist through severe environmental challenges. In 2010, the Deepwater Horizon oil spill devastated large portions of the coastline along the Gulf of Mexico. However, the foundational salt marsh grass, Spartina alterniflora , showed high resilience to this strong environmental disturbance. Following the spill, we simultaneously examined the genetic and epigenetic structure of recovering populations of S. alterniflora to oil exposure. We quantified genetic and DNA methylation variation using amplified fragment length polymorphism and methylation sensitive fragment length polymorphism (MS-AFLP) to test the hypothesis that response to oil exposure in S. alterniflora resulted in genetically and epigenetically based population differentiation. We found high genetic and epigenetic variation within and among sites and found significant genetic differentiation between contaminated and uncontaminated sites, which may reflect nonrandom mortality in response to oil exposure. Additionally, despite a lack of genomewide patterns in DNA methylation between contaminated and uncontaminated sites, we found five MS-AFLP loci (12% of polymorphic MS-AFLP loci) that were correlated with oil exposure. Overall, our findings support genetically based differentiation correlated with exposure to the oil spill in this system, but also suggest a potential role for epigenetic mechanisms in population differentiation.
NASA Astrophysics Data System (ADS)
Legrain, Fleur; Manzhos, Sergei
2017-01-01
Thermodynamics and kinetics of Li, Na, and Mg storage in Ge are studied ab initio. The most stable configurations can consist of tetrahedral, substitutional, or a combination of the two types of sites. In the dilute limit, Li and Na prefer interstitial, while Mg prefers substitutional sites. At higher concentrations of Li, Na, and Mg, there is a combination of interstitial and substitutional sites. This is an important finding, as most previous ab initio studies of alloying type electrode materials ignored substitutional sites. Insertion energies computed at dilute concentration (x = 1/64) show that Na and Mg insertion are not thermodynamically favored in Ge vs. the formation of bulk Na and Mg, as opposed to Li insertion which is favored. We investigate the effect of p-doping of Ge (with Ga) on the thermodynamics and find that it considerably lowers the defect formation energies associated with the insertion of Li/Na/Mg at tetrahedral sites. On the other hand, the energetics associated with Li/Na/Mg insertion at substitutional sites are not significantly affected. In addition, we compute the migration energy barriers for Li/Na/Mg diffusion between two tetrahedral sites (0.38/0.79/0.66 eV), between two substitutional sites (0.77/0.93/1.83 eV), and between two sites of different types (2.15/1.75/0.85 eV).
Legrain, Fleur; Manzhos, Sergei
2017-01-21
Thermodynamics and kinetics of Li, Na, and Mg storage in Ge are studied ab initio. The most stable configurations can consist of tetrahedral, substitutional, or a combination of the two types of sites. In the dilute limit, Li and Na prefer interstitial, while Mg prefers substitutional sites. At higher concentrations of Li, Na, and Mg, there is a combination of interstitial and substitutional sites. This is an important finding, as most previous ab initio studies of alloying type electrode materials ignored substitutional sites. Insertion energies computed at dilute concentration (x = 1/64) show that Na and Mg insertion are not thermodynamically favored in Ge vs. the formation of bulk Na and Mg, as opposed to Li insertion which is favored. We investigate the effect of p-doping of Ge (with Ga) on the thermodynamics and find that it considerably lowers the defect formation energies associated with the insertion of Li/Na/Mg at tetrahedral sites. On the other hand, the energetics associated with Li/Na/Mg insertion at substitutional sites are not significantly affected. In addition, we compute the migration energy barriers for Li/Na/Mg diffusion between two tetrahedral sites (0.38/0.79/0.66 eV), between two substitutional sites (0.77/0.93/1.83 eV), and between two sites of different types (2.15/1.75/0.85 eV).
Typing and comparative genome analysis of Brucella melitensis isolated from Lebanon.
Abou Zaki, Natalia; Salloum, Tamara; Osman, Marwan; Rafei, Rayane; Hamze, Monzer; Tokajian, Sima
2017-10-16
Brucella melitensis is the main causative agent of the zoonotic disease brucellosis. This study aimed at typing and characterizing genetic variation in 33 Brucella isolates recovered from patients in Lebanon. Bruce-ladder multiplex PCR and PCR-RFLP of omp31, omp2a and omp2b were performed. Sixteen representative isolates were chosen for draft-genome sequencing and analyzed to determine variations in virulence, resistance, genomic islands, prophages and insertion sequences. Comparative whole-genome single nucleotide polymorphism analysis was also performed. The isolates were confirmed to be B. melitensis. Genome analysis revealed multiple virulence determinants and efflux pumps. Genome comparisons and single nucleotide polymorphisms divided the isolates based on geographical distribution but revealed high levels of similarity between the strains. Sequence divergence in B. melitensis was mainly due to lateral gene transfer of mobile elements. This is the first report of an in-depth genomic characterization of B. melitensis in Lebanon. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Gene replacements and insertions in rice by intron targeting using CRISPR-Cas9.
Li, Jun; Meng, Xiangbing; Zong, Yuan; Chen, Kunling; Zhang, Huawei; Liu, Jinxing; Li, Jiayang; Gao, Caixia
2016-09-12
Sequence-specific nucleases have been exploited to create targeted gene knockouts in various plants(1), but replacing a fragment and even obtaining gene insertions at specific loci in plant genomes remain a serious challenge. Here, we report efficient intron-mediated site-specific gene replacement and insertion approaches that generate mutations using the non-homologous end joining (NHEJ) pathway using the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) system. Using a pair of single guide RNAs (sgRNAs) targeting adjacent introns and a donor DNA template including the same pair of sgRNA sites, we achieved gene replacements in the rice endogenous gene 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) at a frequency of 2.0%. We also obtained targeted gene insertions at a frequency of 2.2% using a sgRNA targeting one intron and a donor DNA template including the same sgRNA site. Rice plants harbouring the OsEPSPS gene with the intended substitutions were glyphosate-resistant. Furthermore, the site-specific gene replacements and insertions were faithfully transmitted to the next generation. These newly developed approaches can be generally used to replace targeted gene fragments and to insert exogenous DNA sequences into specific genomic sites in rice and other plants.
USDA-ARS?s Scientific Manuscript database
Newcastle disease virus (NDV) has been developed as a vector for vaccine and gene therapy purposes. However, the optimal insertion site for foreign gene expression remained to be determined. In the present study, we inserted the green fluorescence protein (GFP) gene into five different intergenic ...
SNPServer: a real-time SNP discovery tool.
Savage, David; Batley, Jacqueline; Erwin, Tim; Logan, Erica; Love, Christopher G; Lim, Geraldine A C; Mongin, Emmanuel; Barker, Gary; Spangenberg, German C; Edwards, David
2005-07-01
SNPServer is a real-time flexible tool for the discovery of SNPs (single nucleotide polymorphisms) within DNA sequence data. The program uses BLAST, to identify related sequences, and CAP3, to cluster and align these sequences. The alignments are parsed to the SNP discovery software autoSNP, a program that detects SNPs and insertion/deletion polymorphisms (indels). Alternatively, lists of related sequences or pre-assembled sequences may be entered for SNP discovery. SNPServer and autoSNP use redundancy to differentiate between candidate SNPs and sequence errors. For each candidate SNP, two measures of confidence are calculated, the redundancy of the polymorphism at a SNP locus and the co-segregation of the candidate SNP with other SNPs in the alignment. SNPServer is available at http://hornbill.cspp.latrobe.edu.au/snpdiscovery.html.
Single tube genotyping of sickle cell anaemia using PCR-based SNP analysis
Waterfall, Christy M.; Cobb, Benjamin D.
2001-01-01
Allele-specific amplification (ASA) is a generally applicable technique for the detection of known single nucleotide polymorphisms (SNPs), deletions, insertions and other sequence variations. Conventionally, two reactions are required to determine the zygosity of DNA in a two-allele system, along with significant upstream optimisation to define the specific test conditions. Here, we combine single tube bi-directional ASA with a ‘matrix-based’ optimisation strategy, speeding up the whole process in a reduced reaction set. We use sickle cell anaemia as our model SNP system, a genetic disease that is currently screened using ASA methods. Discriminatory conditions were rapidly optimised enabling the unambiguous identification of DNA from homozygous sickle cell patients (HbS/S), heterozygous carriers (HbA/S) or normal DNA in a single tube. Simple downstream mathematical analyses based on product yield across the optimisation set allow an insight into the important aspects of priming competition and component interactions in this competitive PCR. This strategy can be applied to any polymorphism, defining specific conditions using a multifactorial approach. The inherent simplicity and low cost of this PCR-based method validates bi-directional ASA as an effective tool in future clinical screening and pharmacogenomic research where more expensive fluorescence-based approaches may not be desirable. PMID:11726702
Neill, Nicholas J; Ballif, Blake C; Lamb, Allen N; Parikh, Sumit; Ravnan, J Britt; Schultz, Roger A; Torchia, Beth S; Rosenfeld, Jill A; Shaffer, Lisa G
2011-04-01
Insertions occur when a segment of one chromosome is translocated and inserted into a new region of the same chromosome or a non-homologous chromosome. We report 71 cases with unbalanced insertions identified using array CGH and FISH in 4909 cases referred to our laboratory for array CGH and found to have copy-number abnormalities. Although the majority of insertions were non-recurrent, several recurrent unbalanced insertions were detected, including three der(Y)ins(Y;18)(q?11.2;p11.32p11.32)pat inherited from parents carrying an unbalanced insertion. The clinical significance of these recurrent rearrangements is unclear, although the small size, limited gene content, and inheritance pattern of each suggests that the phenotypic consequences may be benign. Cryptic, submicroscopic duplications were observed at or near the insertion sites in two patients, further confounding the clinical interpretation of these insertions. Using FISH, linear amplification, and array CGH, we identified a 126-kb duplicated region from 19p13.3 inserted into MECP2 at Xq28 in a patient with symptoms of Rett syndrome. Our results demonstrate that although the interpretation of most non-recurrent insertions is unclear without high-resolution insertion site characterization, the potential for an otherwise benign duplication to result in a clinically relevant outcome through the disruption of a gene necessitates the use of FISH to determine whether copy-number gains detected by array CGH represent tandem duplications or unbalanced insertions. Further follow-up testing using techniques such as linear amplification or sequencing should be used to determine gene involvement at the insertion site after FISH has identified the presence of an insertion.
When the Human Immunodeficiency Virus (HIV) infects a cell, the virus inserts a copy of its genetic material into the host cell’s DNA. The inserted genetic material, which is also called a provirus, is used to produce new viruses. Because the viral DNA can be inserted at many sites in the host cell DNA, the site of integration marks each infected cell. Patients infected with
Mitochondrial DNA polymorphism in a maternal lineage of Holstein cows.
Hauswirth, W W; Laipis, P J
1982-01-01
Two mitochondrial genotypes are shown to exist within one Holstein cow maternal lineage. They were detected by the appearance of an extra Hae III recognition site in one genotype. The nucleotide sequence of this region has been determined and the genotypes are distinguished by an adenine/guanine base transition which creates the new Hae III site. This point mutation occurs within an open reading frame at the third position of a glycine codon and therefore does not alter the amino acid sequence. The present pattern of genotypes within the lineage demands that multiple shifts between genotypes must have occurred within the past 20 years with the most rapid shift taking place in no more than 4 years and indicates that mitochondrial DNA polymorphism can occur between maternally related mammals. The process that gave rise to different genotypes in one lineage is clearly of fundamental importance in understanding intraspecific mitochondrial polymorphism and evolution in mammals. Several potential mechanisms for rapid mitochondrial DNA variation are discussed in light of these results. Images PMID:6289312
Aberle, K S; Hamann, H; Drögemüller, C; Distl, O
2007-04-01
We analysed a 610-bp mitochondrial (mt)DNA D-loop fragment in a sample of German draught horse breeds and compared the polymorphic sites with sequences from Arabian, Hanoverian, Exmoor, Icelandic, Sorraia and Przewalski's Horses as well as with Suffolk, Shire and Belgian horses. In a total of 65 horses, 70 polymorphic sites representing 47 haplotypes were observed. The average percentage of polymorphic sites was 11.5% for the mtDNA fragment analysed. In the nine different draught horse breeds including South German, Mecklenburg, Saxon Thuringa coldblood, Rhenisch German, Schleswig Draught Horse, Black Forest Horse, Shire, Suffolk and Belgian, 61 polymorphic sites and 24 haplotypes were found. The phylogenetic analysis failed to show monophyletic groups for the draught horses. The analysis indicated that the draught horse populations investigated consist of diverse genetic groups with respect to their maternal lineage.
Liu, Jin-Fei; Xie, Hao-Jun; Cheng, Tian-Ming
2013-01-01
To investigate the association between the gene polymorphisms of angiotensin-converting enzyme (ACE) and digestive system cancer risk. A search was performed in Pubmed, Medline, ISI Web of Science and Chinese Biomedical (CBM) databases, covering all studies until Sep 1st, 2013. Statistical analysis was performed by using Revman5.2 and STATA 12.0. A total of 15 case-control studies comprising 2,390 digestive system cancer patients and 9,706 controls were identified. No significant association was found between the I/D polymorphism and digestive cancer risk (OR =0.93, 95%CI = (0.75, 1.16), P =0.53 for DD+DI vs. II). In the subgroup analysis by ethnicity and cancer type, no significant associations were found for the comparison of DD+DI vs. II. Results from other comparative genetic models also indicated a lack of associations between this polymorphism and digestive system cancer risks. This meta-analysis suggested that the ACE D/I polymorphism might not contribute to the risk of digestive system cancer.
Plasminogen activator inhibitor I 4G/5G polymorphism in neonatal respiratory distress syndrome.
Armangil, Didem; Yurdakök, Murat; Okur, Hamza; Gürgey, Aytemiz
2011-08-01
Fibrin monomers inhibit surfactant function. 4G/5G insertion/deletion polymorphism plays an important role in the regulation of plasminogen activator inhibitor 1 (PAI-1) gene expression. To examine the genotype distribution of PAI-1 polymorphism in 60 infants with respiratory distress syndrome (RDS) and 53 controls, an allele-specific polymerase chain reaction (PCR) was used. The proportion of 4G/4G, 4G/5G, and 5G/5G genotypes did not differ statistically between the RDS and control groups (P > .05). Having PAI-1 4G/4G genotype polymorphism appears to increase the risk of RDS (odds ratio [OR] =1.5; 95% confidence interval [CI], 0.5-4.3), although it was not statistically significant. No relation was found between the PAI-1 4G/5G polymorphisms and RDS, but there was an increased risk associated with the 4G variant of the PAI-1 gene. We believe that our findings of increased 4G allele of the PAI-1 gene in infants with RDS would also help to clarify the pathogenesis of RDS.
Dehghani, Hossein; Ghobakhloo, Sepideh; Neishabury, Maryam
2016-08-01
In our previous studies on the Iranian β-thalassemia (β-thal) patients, we identified an association between the severity of the β-thal phenotype and the polymorphic palindromic site at the 5' hypersensitive site 4-locus control region (5'HS4-LCR) of the β-globin gene cluster. Furthermore, a linkage disequilibrium was observed between this region and XmnI-HBG2 in the patient population. Based on this data, it was suggested that the well-recognized phenotype-ameliorating role assigned to positive XmnI could be associated with its linked elements in the LCR. To investigate the functional significance of polymorphisms at the 5'HS4-LCR, we studied its influence on binding of transcription factors. Web-based predictions of transcription factor binding revealed a binding site for runt-related transcription factor 1 (RUNX1), when the allele at the center of the palindrome (TGGGG(A/G)CCCCA) was A but not when it was G. Furthermore, electromobility shift assay (EMSA) presented evidence in support of allele-specific binding of RUNX1 to 5'HS4. Considering that RUNX1 is a well-known regulator of hematopoiesis, these preliminary data suggest the importance of further studies to confirm this interaction and consequently investigate its functional and phenotypical relevance. These studies could help us to understand the molecular mechanism behind the phenotype modifying role of the 5'HS4-LCR polymorphic palindromic region (rs16912979), which has been observed in previous studies.
The PROGINS polymorphism of the human progesterone receptor diminishes the response to progesterone.
Romano, Andrea; Delvoux, Bert; Fischer, Dagmar-Christiane; Groothuis, Patrick
2007-02-01
The human progesterone receptor (PR) is a ligand-dependent transcription factor and two isoforms, (PRA and PRB), can be distinguished. PROGINS, a PR polymorphic variant, affects PRA and PRB and acts as a risk-modulating factor in several gynaecological disorders. Little is known about the functional consequences of this variant. Here, we characterise the properties of PROGINS with respect to transcription, mRNA maturation, protein activity and proliferation. PROGINS is characterised by a 320 bp PV/HS-1 Alu insertion in intron G and two point mutations, V660L in exon 4 and H770H (silent substitution) in exon 5. The Alu element contains a half oestrogen-response element/Sp1-binding site (Alu-ERE/Sp1), which acts as an in-cis intronic enhancer leading to increased transcription of the PROGINS allele in response to 17beta-oestradiol. Moreover, Alu insertions in the human genome are frequently methylated. Our data indicate that the PROGINS-Alu does not affect gene transcription due to DNA methylation. However, the Alu element reduced the stability of the PROGINS transcript compared with the CP allele and does not generate splice variants. The amino acid substitution (V600L) in exon 4 leads to differences in PR phosphorylation and degradation in the two PR variants upon ligand binding, most likely as a result of differences in the three-dimensional structures of the two PR variants. As a consequence, the PR-L660 (PROGINS) variant (1) displays decreased transactivation activity in a luciferase reporter system and (2) is less efficient in opposing cell proliferation in hamster ovarian cells expressing human PRA, when compared with the PR-V660 (most common variant). Taken together, our results indicate that the PROGINS variant of PR is less responsive to progestin compared with the most common PR because of (i) reduced amounts of gene transcript and (ii) decreased protein activity.
Genome skimming identifies polymorphism in tern populations and species
2012-01-01
Background Terns (Charadriiformes: Sterninae) are a lineage of cosmopolitan shorebirds with a disputed evolutionary history that comprises several species of conservation concern. As a non-model system in genetics, previous study has left most of the nuclear genome unexplored, and population-level studies are limited to only 15% of the world's species of terns and noddies. Screening of polymorphic nuclear sequence markers is needed to enhance genetic resolution because of supposed low mitochondrial mutation rate, documentation of nuclear insertion of hypervariable mitochondrial regions, and limited success of microsatellite enrichment in terns. Here, we investigated the phylogenetic and population genetic utility for terns and relatives of a variety of nuclear markers previously developed for other birds and spanning the nuclear genome. Markers displaying a variety of mutation rates from both the nuclear and mitochondrial genome were tested and prioritized according to optimal cross-species amplification and extent of genetic polymorphism between (1) the main tern clades and (2) individual Royal Terns (Thalasseus maxima) breeding on the US East Coast. Results Results from this genome skimming effort yielded four new nuclear sequence-based markers for tern phylogenetics and 11 intra-specific polymorphic markers. Further, comparison between the two genomes indicated a phylogenetic conflict at the base of terns, involving the inclusion (mitochondrial) or exclusion (nuclear) of the Angel Tern (Gygis alba). Although limited mitochondrial variation was confirmed, both nuclear markers and a short tandem repeat in the mitochondrial control region indicated the presence of considerable genetic variation in Royal Terns at a regional scale. Conclusions These data document the value of intronic markers to the study of terns and allies. We expect that these and additional markers attained through next-generation sequencing methods will accurately map the genetic origin and species history of this group of birds. PMID:22333071
Burns, Kathleen H.; Boeke, Jef D.
2012-01-01
Mobile DNAs have had a central role in shaping our genome. More than half of our DNA is comprised of interspersed repeats resulting from replicative copy and paste events of retrotransposons. Although most are fixed, incapable of templating new copies, there are important exceptions to retrotransposon quiescence. De novo insertions cause genetic diseases and cancers, though reliably detecting these occurrences has been difficult. New technologies aimed at uncovering polymorphic insertions reveal that mobile DNAs provide a substantial and dynamic source of structural variation. Key questions going forward include the how and how much new transposition events affect human health and disease. PMID:22579280
[Reducing the Incidence of Phlebitis Related to Intravenous Injection in Pediatric Patients].
Cho, Yen-Hua; Yen, Li-Ling; Yu, Kai-Ling; Chang, Chun-Chu; Chen, Hsuen-Ling
2015-06-01
Peripheral venous catheter (PVC) is commonly used to provide nutrition and medicine to pediatric inpatients. Phlebitis is a common side effect of PVC insertion. Over 90% of pediatric patients in the paedi-atric medical ward at the Chang Gung Memorial Hospital (CGMH) receive PVC insertion, with an incident rate of phlebitis of 5.07%. Common cause factors of phlebitis are: insufficient sterilization time, inappropriate methods used to fix the PVC, the use of fixtures that loosen easily, high re-fix rates, and inadequate wound care after catheter removal. The purpose of this project was to reduce the incidence rate of PVC-insertion-related phlebitis in children from 5.07% to 2.5%. A one-week clinical observation identified the re-inserting / re-fixing of existing PVCs as the principal cause of phlebitis in the CGMH paediatric ward. Therefore, the researchers modified the catheter care bundle based on a review of the literature and the suggestions of clinical pediatric experts. Modifications included applying 2% chlorhexidine to sterilize the insertion site; using a new, non-woven fabric splint to fix the PVC site; providing cartoon-themed waterproof dressings for the first bath after the removal of the PVC; and setting standard operating procedures (SOPs) for PVC insertion and catheter removal. After applying these modifications, the incident rate of phlebitis in children with PVC insertions decreased from 5.07% to 2.08%. The application of 2% chlorhexidine reduces the waiting time for sterilization; the purpose-designed splint strengthens the fixation of the PVC; and the development of the SOPs for PVC insertion and post-removal catheter care reduces the risk of phlebitis. The combination of these strategies effectively reduces the incidence of phlebitis and improves the nursing care quality.
Hashemi, Mohammad; Danesh, Hiva; Bizhani, Fatemeh; Mokhtari, Mojgan; Bahari, Gholamreza; Tabasi, Farhad; Taheri, Mohsen
2018-03-01
Recurrent spontaneous abortion (RSA) is a common health problem affecting women of reproductive age. Altered expression of vascular endothelial growth factor ( VEGF ) has been associated with spontaneous abortion. The present case-control study aimed to evaluate the impact of the 18-bp insertion/deletion (ins/del) polymorphism (rs35569394) in the promoter region of the VEGF gene on idiopathic RSA. Genomic DNA from 93 patients with RSA and 93 healthy fertile women of southeastern Iran was isolated using the salting-out method. Genotyping of the rs35569394 variant was performed by a polymerase chain reaction (PCR) method. The findings indicated that the VEGF 18-bp ins/del variant significantly increased the risk of RSA under codominant (ins/ins vs. del/del; OR=2.85, 95% CI=1.31-6.22, P=0.019), dominant (del/ins+ins/ins vs. del/del; OR=2.19, 95% CI=1.20-4.01, P=0.015) and allelic (ins vs. del; OR=1.90, 95% CI=1.25-2.88, P=0.003) inheritance models. In summary, the findings propose a significant association between the VEGF 18-bp ins/del polymorphism and risk of RSA in a sample of the southeast Iranian population. Further studies on larger sample sizes and different ethnicities are required to validate the present findings.
Wang, Lu; Mariño-Ramírez, Leonardo
2017-01-01
Abstract Transposable element (TE) derived sequences are known to contribute to the regulation of the human genome. The majority of known TE-derived regulatory sequences correspond to relatively ancient insertions, which are fixed across human populations. The extent to which human genetic variation caused by recent TE activity leads to regulatory polymorphisms among populations has yet to be thoroughly explored. In this study, we searched for associations between polymorphic TE (polyTE) loci and human gene expression levels using an expression quantitative trait loci (eQTL) approach. We compared locus-specific polyTE insertion genotypes to B cell gene expression levels among 445 individuals from 5 human populations. Numerous human polyTE loci correspond to both cis and trans eQTL, and their regulatory effects are directly related to cell type-specific function in the immune system. PolyTE loci are associated with differences in expression between European and African population groups, and a single polyTE loci is indirectly associated with the expression of numerous genes via the regulation of the B cell-specific transcription factor PAX5. The polyTE-gene expression associations we found indicate that human TE genetic variation can have important phenotypic consequences. Our results reveal that TE-eQTL are involved in population-specific gene regulation as well as transcriptional network modification. PMID:27998931
Naudts, Kris H; Azevedo, Ruben T; David, Anthony S; van Heeringen, Kees; Gibbs, Ayana A
2012-09-01
Individual differences in emotional processing are likely to contribute to vulnerability and resilience to emotional disorders such as depression and anxiety. Genetic variation is known to contribute to these differences but they remain incompletely understood. The serotonin transporter (5-HTTLPR) and α2B-adrenergic autoreceptor (ADRA2B) insertion/deletion polymorphisms impact on two separate but interacting monaminergic signalling mechanisms that have been implicated in both emotional processing and emotional disorders. Recent studies suggest that the 5-HTTLPR s allele is associated with a negative attentional bias and an increased risk of emotional disorders. However, such complex behavioural traits are likely to exhibit polygenicity, including epistasis. This study examined the contribution of the 5-HTTLPR and ADRA2B insertion/deletion polymorphisms to attentional biases for aversive information in 94 healthy male volunteers and found evidence of a significant epistatic effect (p<0.001). Specifically, in the presence of the 5-HTTLPR s allele, the attentional bias for aversive information was attenuated by possession of the ADRA2B deletion variant whereas in the absence of the s allele, the bias was enhanced. These data identify a cognitive mechanism linking genotype-dependent serotonergic and noradrenergic signalling that is likely to have implications for the development of cognitive markers for depression/anxiety as well as therapeutic drug effects and personalized approaches to treatment.
Essa, Enas S; El Wahsh, Rabab A
2016-12-01
Molecular pathology of chronic obstructive pulmonary disease (COPD) is still being investigated to discover relationships with disease pathogenesis. Evidence of plasminogen activator inhibitor-1 (PAI-1) overexpression in the sputum and the blood of COPD patients is growing. We aimed to investigate the potential relation between PAI-1 promoter 4G/5G insertion/deletion polymorphism and COPD development. In a case-control study, we genotyped 117 COPD patients and 160 control subjects for PAI-1 promoter 4G/5G polymorphism by an allele-specific polymerase chain reaction analysis. All subjects were male smokers. In the co-dominant model, there was a significant difference in the distribution of 5G/5G, 4G/5G and 4G/4G genotypes between COPD patients and controls (p = 0.002). In the recessive model, carriers of 4G/4G genotype were significantly higher in COPD patients than controls (p = 0.01). Carriers of 4G/4G genotype were at higher risk to develop COPD than those carrying 5G/5G or 4G/5G genotypes (crude odds ratio (OR) = 2.10, 95% confidence interval (CI) = 1.19-3.73, adjusted OR = 2.5, 95% CI = 1.22-3.99). In conclusion, PAI-1 4G/5G genetic variations are associated with COPD development in males.
Marcon, Helena Sanches; Domingues, Douglas Silva; Silva, Juliana Costa; Borges, Rafael Junqueira; Matioli, Fábio Filippi; Fontes, Marcos Roberto de Mattos; Marino, Celso Luis
2015-08-14
In Eucalyptus genus, studies on genome composition and transposable elements (TEs) are particularly scarce. Nearly half of the recently released Eucalyptus grandis genome is composed by retrotransposons and this data provides an important opportunity to understand TE dynamics in Eucalyptus genome and transcriptome. We characterized nine families of transcriptionally active LTR retrotransposons from Copia and Gypsy superfamilies in Eucalyptus grandis genome and we depicted genomic distribution and copy number in two Eucalyptus species. We also evaluated genomic polymorphism and transcriptional profile in three organs of five Eucalyptus species. We observed contrasting genomic and transcriptional behavior in the same family among different species. RLC_egMax_1 was the most prevalent family and RLC_egAngela_1 was the family with the lowest copy number. Most families of both superfamilies have their insertions occurring <3 million years, except one Copia family, RLC_egBianca_1. Protein theoretical models suggest different properties between Copia and Gypsy domains. IRAP and REMAP markers suggested genomic polymorphisms among Eucalyptus species. Using EST analysis and qRT-PCRs, we observed transcriptional activity in several tissues and in all evaluated species. In some families, osmotic stress increases transcript values. Our strategy was successful in isolating transcriptionally active retrotransposons in Eucalyptus, and each family has a particular genomic and transcriptional pattern. Overall, our results show that retrotransposon activity have differentially affected genome and transcriptome among Eucalyptus species.
Peraza-Echeverria, S; Herrera-Valencia, V A.; Kay, A -J.
2001-07-01
The extent of DNA methylation polymorphisms was evaluated in micropropagated banana (Musa AAA cv. 'Grand Naine') derived from either the vegetative apex of the sucker or the floral apex of the male inflorescence using the methylation-sensitive amplification polymorphism (MSAP) technique. In all, 465 fragments, each representing a recognition site cleaved by either or both of the isoschizomers were amplified using eight combinations of primers. A total of 107 sites (23%) were found to be methylated at cytosine in the genome of micropropagated banana plants. In plants micropropagated from the male inflorescence explant 14 (3%) DNA methylation events were polymorphic, while plants micropropagated from the sucker explant produced 8 (1.7%) polymorphisms. No DNA methylation polymorphisms were detected in conventionally propagated banana plants. These results demonstrated the usefulness of MSAP to detect DNA methylation events in micropropagated banana plants and indicate that DNA methylation polymorphisms are associated with micropropagation.
Restriction fragment length polymorphism of the human c-fms gene.
Xu, D Q; Guilhot, S; Galibert, F
1985-01-01
By using blot hybridization with a v-fms probe, a polymorphism for EcoRI, HindIII, and BamHI restriction endonuclease sites associated with the human c-fms locus was observed in a random adult population. This restriction fragment length polymorphism can be explained on the basis of the existence of two alleles, a and b, and is due to a short (congruent to 500 base pairs) deletion characteristic of allele a. The distribution in the analyzed population (48 unrelated individuals) is 23% heterozygotes ab, 75% homozygotes bb, and 2% homozygotes aa. Though the inheritance of this polymorphism follows a Mendelian pattern, the children from couples ab X bb are of the following genotype: 74% ab and 26% bb. These deviations from the expected frequencies of 50% suggest a selective pressure in favor of heterozygotes. Images PMID:2986142
Intravenous insertion site protection: moisture accumulation in intravenous site protectors.
Lee, W E; Vallino, L M
1996-01-01
Stabilizing the intravenous catheter after insertion is a significant part of intravenous therapy. Dislodgments of the cannula from its optimal position in the vein can lead to complications such as phlebitis, thrombophlebitis, infiltration, and infection. Intravenous site protector shields are designed to protect the catheter from impact and tissue trauma at the insertion site. Nurses have requested ventilation in these shields to avoid moisture build up that may increase the risk of infections. To address this issue, experimental laboratory testing was performed to determine if moisture accumulation as evidenced by increased weight of the shield and visible evidence of condensation occurred. No moisture condensation problems with the ventilated intravenous site protectors were found.
Motawi, Tarek K; Shaker, Olfat G; Shahin, Nancy N; Ahmed, Nancy M
2016-01-01
According to the WHO report in 2015, obesity is the fifth leading cause of death worldwide, and the prevalence of Egyptian female obesity is 37.5 %. Since obesity is highly influenced by genetics, and adipose tissue renin-angiotensin system is over-activated in obesity, the effect of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism on obesity and related disorders was studied in several populations, because of its effect on ACE activity. Our objective was to study the association of ACE I/D polymorphism with obesity and certain related disorders, namely hypertension, insulin resistance and metabolic syndrome, in Egyptian females. Eighty female volunteers were recruited, blood pressure and body measurements were recorded and a fasting blood sample was obtained for the quantitation of glucose, lipid profile, insulin, leptin and identification of ACE I/D polymorphs. Subjects were grouped based on hypertension and obesity states. Comparisons of continuous parameters were made with independent sample t -test between two groups. The frequencies of ACE genotypes and alleles, and the association between gene polymorphism and metabolic parameters were assessed using chi-square or Fisher's exact test. Genotype frequencies were in Hardy-Weinberg equilibrium for all groups. Genotype distribution did not differ significantly between controls and cases of all the studied disorders. Although DD carriers had apparently higher parameters of blood pressure, lipid profile and insulin resistance, only diastolic blood pressure was almost significant ( p = 0.057). I-carriers were significantly less susceptible to hypertension than DD carriers having normal waist/hip ratio ( p = 0.007, OR = 17.29, CI = 1.81-164.96) and normal conicity index ( p = 0.024, OR = 7.00, CI = 1.36-35.93). In DD genotype carriers, a significant association was found between insulin resistance and high body mass index ( p = 0.004, OR = 8.89, CI = 1.94-40.71), waist circumference ( p = 0.003, OR = 9.63, CI = 2.14-43.36) and waist/height ratio ( p = 0.034, OR = 6.86, CI = 1.25-37.61), although the variations in percentages between DD and I-carriers were not high enough to conclude an effect of ACE I/D on such an association. In this sample of Egyptian females, ACE I/D polymorphism was not significantly associated with obesity nor with any of its related disorders studied. The I allele seemed protective against hypertension in subjects with normal, not high, waist/hip ratio and conicity index compared to DD genotype carriers.
National Biocontainment Training Center
2014-06-01
of novel antimicrobial compounds with antibacterial activity against TB (Vijayakumar, et al., Dec. 2013, Tuberculosis). She has also developed...Nanoluc. (a) insert the Nanoluc after the signal peptide , (b) insert the Nanoluc before the RSKR site, (c) insert the Nanoluc before the RRLL site...biological safe techniques. This training took place in Dallas, Texas. Trainers: Vickie Jones and Jason Hardcastle. Food and Drug Administration (FDA
USDA-ARS?s Scientific Manuscript database
Inserts and insert sites in transgenic, commercial papaya line 55-1 derivatives Rainbow and SunUp were characterized as part of a petition to Japan to allow import of fresh fruit of these cultivars from the U.S. and to provide data for a larger study aimed at understanding the global impact of DNA t...
Incomplete Lineage Sorting and Hybridization Statistics for Large-Scale Retroposon Insertion Data
Kuritzin, Andrej; Kischka, Tabea
2016-01-01
Ancient retroposon insertions can be used as virtually homoplasy-free markers to reconstruct the phylogenetic history of species. Inherited, orthologous insertions in related species offer reliable signals of a common origin of the given species. One prerequisite for such a phylogenetically informative insertion is that the inserted element was fixed in the ancestral population before speciation; if not, polymorphically inserted elements may lead to random distributions of presence/absence states during speciation and possibly to apparently conflicting reconstructions of their ancestry. Fortunately, such misleading fixed cases are relatively rare but nevertheless, need to be considered. Here, we present novel, comprehensive statistical models applicable for (1) analyzing any pattern of rare genomic changes, (2) testing and differentiating conflicting phylogenetic reconstructions based on rare genomic changes caused by incomplete lineage sorting or/and ancestral hybridization, and (3) differentiating between search strategies involving genome information from one or several lineages. When the new statistics are applied, in non-conflicting cases a minimum of three elements present in both of two species and absent in a third group are considered significant support (p<0.05) for the branching of the third from the other two, if all three of the given species are screened equally for genome or experimental data. Five elements are necessary for significant support (p<0.05) if a diagnostic locus derived from only one of three species is screened, and no conflicting markers are detected. Most potentially conflicting patterns can be evaluated for their significance and ancestral hybridization can be distinguished from incomplete lineage sorting by considering symmetric or asymmetric distribution of rare genomic changes among possible tree configurations. Additionally, we provide an R-application to make the new KKSC insertion significance test available for the scientific community at http://retrogenomics.uni-muenster.de:3838/KKSC_significance_test/. PMID:26967525
Khusainova, R I; Akhmetova, V L; Kutuev, I A; Salimova, A Z; Korshunova, T Iu; Lebedev, Iu B; Khusnutdinova, E K
2004-04-01
Nine Alu loci (Ya5NBC5, Ya5NBC27, Ya5NBC148, Ya5NBC182, YA5NBC361, ACE, ApoA1, PV92, TPA25) were analyzed in six ethnic populations (Trans-Ural Bashkirs, Tatars-Mishars, Mordovians-Moksha, Mountain Maris, Udmurts, and Komi-Permyaks) of the Volga-Ural region and in three Central Asian populations (Uzbeks, Kazakhs, and Uigurs). All Alu insertions analyzed appeared to be polymorphic in all populations examined. The frequency of insertion varied from 0.110 in Mountain Maris at the Ya5NBC5 locus to 0.914 in Tatars at the ApoA1 locus. The data on the allele frequency distribution at nine loci point to the existence of substantial genetic diversity in the populations examined. The value of the observed heterozygosity averaged over nine Alu insertions varied from 0.326 in Mountain Maris to 0.445 in Kazakhs and Uigurs. The level of the interpopulation genetic differences for the Volga-Ural population (Fst = 0.061) was higher than for the populations of Central Asia (Fst = 0.024), Europe (Fst = 0.02), and Southeastern Asia (Fst = 0.018). The populations examined were highly differentiated both in respect of linguistic characteristics and the geographical position. The data obtained confirmed the effectiveness of the marker system used for the assessment of genetic differentiation and the relationships between the ethnic groups.
Vitórica-Yrezábal, Iñigo J; Libri, Stefano; Loader, Jason R; Mínguez Espallargas, Guillermo; Hippler, Michael; Fletcher, Ashleigh J; Thompson, Stephen P; Warren, John E; Musumeci, Daniele; Ward, Michael D; Brammer, Lee
2015-06-08
Despite an absence of conventional porosity, the 1D coordination polymer [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)3 ] (1; TMP=tetramethylpyrazine) can absorb small alcohols from the vapour phase, which insert into AgO bonds to yield coordination polymers [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)3 (ROH)2 ] (1-ROH; R=Me, Et, iPr). The reactions are reversible single-crystal-to-single-crystal transformations. Vapour-solid equilibria have been examined by gas-phase IR spectroscopy (K=5.68(9)×10(-5) (MeOH), 9.5(3)×10(-6) (EtOH), 6.14(5)×10(-5) (iPrOH) at 295 K, 1 bar). Thermal analyses (TGA, DSC) have enabled quantitative comparison of two-step reactions 1-ROH→1→2, in which 2 is the 2D coordination polymer [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)2 ] formed by loss of TMP ligands exclusively from singly-bridging sites. Four polymorphic forms of 1 (1-A(LT) , 1-A(HT) , 1-B(LT) and 1-B(HT) ; HT=high temperature, LT=low temperature) have been identified crystallographically. In situ powder X-ray diffraction (PXRD) studies of the 1-ROH→1→2 transformations indicate the role of the HT polymorphs in these reactions. The structural relationship between polymorphs, involving changes in conformation of perfluoroalkyl chains and a change in orientation of entire polymers (A versus B forms), suggests a mechanism for the observed reactions and a pathway for guest transport within the fluorous layers. Consistent with this pathway, optical microscopy and AFM studies on single crystals of 1-MeOH/1-A(HT) show that cracks parallel to the layers of interdigitated perfluoroalkyl chains develop during the MeOH release/uptake process. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liao, D.; Weiner, A.M.
1995-12-10
The RNU2 locus encoding human U2 small nuclear RNA (snRNA) is organized as a nearly perfect tandem array containing 5 to 22 copies of a 5.8-kb repeat unit. Just downstream of the U2 snRNA gene in each 5.8-kb repeat unit lies a large (CT){sub n}{center_dot}(GA){sub n} dinucleotide repeat (n {approx} 70). This form of genomic organization, in which one repeat is embedded within another, provides an unusual opportunity to study the balance of forces maintaining the homogeneity of both kinds of repeats. Using a combination of field inversion gel electrophoresis and polymerase chain reaction, we have been able to studymore » the CT microsatellites within individual U2 tandem arrays. We find that the CT microsatellites within an RNU2 allele exhibit significant length polymorphism, despite the remarkable homogeneity of the surrounding U2 repeat units. Length polymorphism is due primarily to loss or gain of CT dinucleotide repeats, but other types of deletions, insertions, and substitutions are also frequent. Polymorphism is greatly reduced in regions where pure (CT){sub n} tracts are interrupted by occasional G residues, suggesting that irregularities stabilize both the length and the sequence of the dinucleotide repeat. We further show that the RNU2 loci of other catarrhine primates (gorilla, chimpanzee, ogangutan, and baboon) contain orthologous CT microsatellites; these also exhibit length polymorphism, but are highly divergent from each other. Thus, although the CT microsatellite is evolving far more rapidly than the rest of the U2 repeat unit, it has persisted through multiple speciation events spanning >35 Myr. The persistence of the CT microsatellite, despite polymorphism and rapid evolution, suggests that it might play a functional role in concerted evolution of the RNU2 loci, perhaps as an initiation site for recombination and/or gene conversion. 70 refs., 5 figs.« less
Vilela-Martin, José F; Vaz-de-Melo, Renan O; Cosenso-Martin, Luciana N; Kuniyoshi, Cristina H; Yugar-Toledo, Juan C; Pinhel, Marcela A S; de Souza, Gisele F; Souza, Dorotéia R S; Pimenta, Eduardo; Moreno, Heitor; Cipullo, José P
2013-09-01
Hypertensive crisis (HC) stands out as a form of acute elevation of blood pressure (BP). It can manifest itself as hypertensive emergency (HE) or hypertensive urgency (HU), which is usually accompanied with levels of diastolic BP ≥120 mmHg. Angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism may influence manifestations of HC. Thus, this study evaluated the influence of ACE I/D polymorphism in individuals with HC. A total of 187 patients admitted with HC (HU [n=69] and HE [n=118]) and 75 normotensive individuals were included in the study. Peripheral blood was drawn for a biochemical and genetic analysis of the ACE I/D polymorphism by Polymerase Chain Reaction. HC group showed higher systolic BP, body mass index (BMI), glycemia, creatinine, and lower high-density lipoprotein (HDL) cholesterol compared with normotensive individuals. The use of renin-angiotensin system (RAS) blockers was more frequent in the HU group than in the HE group (p=0.020). The II genotype was more predominant in normotensive and HU individuals than among HE individuals (18.7%, 11.6%, and 2.5%, respectively; p=0.004). Higher BMI and glycemia were associated with HC in the logistic regression model. ACE II genotype (odds ratio [OR] 0.14; 95% confidence interval [CI] 0.04-0.51) and HDL cholesterol were protective for the development of HE. ACE II genotype was present in the HU group, compared with the HE group (OR 0.18; 95% CI 0.04-0.88). This study shows an association between the low prevalence of ACE I/D polymorphism II genotype and a greater occurrence of HE in Brazilian individuals. The lower blockage of RAS, which was detected in the HE group, may interact with the low frequency of II genotype, conferring an increased risk for HE.
Chou, Ping-Song; Wu, Shyh-Jong; Kao, Yi-Hui; Chou, Mei-Chuan; Tai, Shu-Yu; Yang, Yuan-Han
2017-06-01
The presence of cerebral white matter changes (WMC) has been reported as an important predictor of the rapidity of cognitive decline in Alzheimer's disease (AD). The association between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and WMC in AD is yet to be elucidated. The present study aimed to examine the association between the ACE I/D polymorphism and WMC among AD patients in Taiwan. A total of 403 patients clinically diagnosed with AD were recruited in a cross-sectional study carried out in an area hospital in Kaohsiung, Taiwan. The ACE I/D polymorphism was genotyped, and cerebral white matter rating was carried out using the visual rating scale for age-related white matter changes. The I allele was associated with a significantly lower total age-related white matter changes scale score compared with the D allele (4.83 vs 5.93, P = 0.013). The total age-related white matter changes scale score was significantly lower for the I/I genotype than for the I/D (4.37 vs 5.87, P = 0.009) and I/D + D/D genotypes (4.37 vs 5.91, P = 0.006), with no differences observed between the I/I + I/D and the D/D genotypes (5.08 vs 6.09, P = 0.373), after adjustment for age and hypertension. A stratified analysis by sex demonstrated that the I/I genotype was associated with significant lower WMC than other genotypes in women, but not in men. The present study supports the hypothesis that the ACE I/D polymorphism is associated with the severity of WMC in patients with AD. Patients with AD who are homozygous for the I allele might be less likely to develop WMC, especially women. Geriatr Gerontol Int 2017; 17: 945-950. © 2016 Japan Geriatrics Society.
Time- and Cost-Efficient Identification of T-DNA Insertion Sites through Targeted Genomic Sequencing
Lepage, Étienne; Zampini, Éric; Boyle, Brian; Brisson, Normand
2013-01-01
Forward genetic screens enable the unbiased identification of genes involved in biological processes. In Arabidopsis, several mutant collections are publicly available, which greatly facilitates such practice. Most of these collections were generated by agrotransformation of a T-DNA at random sites in the plant genome. However, precise mapping of T-DNA insertion sites in mutants isolated from such screens is a laborious and time-consuming task. Here we report a simple, low-cost and time efficient approach to precisely map T-DNA insertions simultaneously in many different mutants. By combining sequence capture, next-generation sequencing and 2D-PCR pooling, we developed a new method that allowed the rapid localization of T-DNA insertion sites in 55 out of 64 mutant plants isolated in a screen for gyrase inhibition hypersensitivity. PMID:23951038
Silva, C; Garcia-Mas, J; Sánchez, A M; Arús, P; Oliveira, M M
2005-03-01
Blooming time is one of the most important agronomic traits in almond. Biochemical and molecular events underlying flowering regulation must be understood before methods to stimulate late flowering can be developed. Attempts to elucidate the genetic control of this process have led to the identification of a major gene (Lb) and quantitative trait loci (QTLs) linked to observed phenotypic differences, but although this gene and these QTLs have been placed on the Prunus reference genetic map, their sequences and specific functions remain unknown. The aim of our investigation was to associate these loci with known genes using a candidate gene approach. Two almond cDNAs and eight Prunus expressed sequence tags were selected as candidate genes (CGs) since their sequences were highly identical to those of flowering regulatory genes characterized in other species. The CGs were amplified from both parental lines of the mapping population using specific primers. Sequence comparison revealed DNA polymorphisms between the parental lines, mainly of the single nucleotide type. Polymorphisms were used to develop co-dominant cleaved amplified polymorphic sequence markers or length polymorphisms based on insertion/deletion events for mapping the candidate genes on the Prunus reference map. Ten candidate genes were assigned to six linkage groups in the Prunus genome. The positions of two of these were compatible with the regions where two QTLs for blooming time were detected. One additional candidate was localized close to the position of the Evergrowing gene, which determines a non-deciduous behaviour in peach.
Hooks, David O; Rehm, Bernd H A
2015-10-01
The polyhydroxyalkanoate (PHA) synthase catalyzes the synthesis of PHA and remains attached to the hydrophobic PHA inclusions it creates. Although this feature is actively exploited to generate functionalized biobeads via protein engineering, little is known about the structure of the PHA synthase. Here, the surface topology of Ralstonia eutropha PHA synthase was probed to inform rational protein engineering toward the production of functionalized PHA beads. Surface-exposed residues were detected by conjugating biotin to inclusion-bound PHA synthase and identifying the biotin-conjugated lysine and cysteine residues using peptide fingerprinting analysis. The identified sites (K77, K90, K139, C382, C459, and K518) were investigated as insertion sites for the generation of new protein fusions. Insertions of FLAG epitopes into exposed sites K77, K90, K139, and K518 were tolerated, retaining >65 % of in vivo activity. Sites K90, K139, and K518 were also tested by insertion of the immunoglobulin G (IgG)-binding domain (ZZ), successfully producing PHA inclusions able to bind human IgG in vitro. Although simultaneous insertions of the ZZ domain into two sites was permissive, insertion at all three lysine sites inactivated the synthase. The K90/K139 double ZZ insertion had the optimum IgG-binding capacity of 16 mg IgG/g wet PHA beads and could selectively purify the IgG fraction from human serum. Overall, this study identified surface-exposed flexible regions of the PHA synthase which either tolerate protein/peptide insertions or are critical for protein function. This further elucidates the structure and function of PHA synthase and provides new opportunities for generating functionalized PHA biobeads.
Kowalczyńska, Liliana J; Ferenc, Tomasz; Wojciechowski, Michał; Mordalska, Anna; Pogoda, Krzysztof; Malinowski, Andrzej
2014-05-01
To analyze the polymorphisms of angiotensin I converting enzyme (ACE) gene (insertion/deletion [I/D], A2350G) and angiotensin II type 1 receptor gene (A1166C) in women with endometriosis and to determine the correlation of the identified genotypes with the severity of the disease. Additionally, to estimate the prognostic value of the polymorphisms in patients with endometriosis treated due to infertility. The study group included 241 women, the control group (without endometriosis)-127. The molecular analysis was performed by polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism technique. For I/D ACE and A1166C AT1 polymorphisms no significant differences were observed between the study and control groups and between the severity grades of the disease (p>0.05). For A2350G ACE polymorphism the frequency of genotypes for the study and control groups respectively was the following: AA-31.54%, AG-54.36%, GG-14.11% and AA-55.12%, AG-36.22%, GG-8.66% (x(2)=19.36, p<0.0001). Statistically significant differences were found between the frequency of A and G alleles between both groups (x(2)=15.16, p=0.0001), but not when individual grades of the disease severity were compared. There was no association between the investigated polymorphisms and the effect of infertility treatment. A2350G polymorphism (allele G, AG genotype) of ACE gene seems to be associated with the development of endometriosis.
Raspé, O; Saumitou-Laprade, P; Cuguen, J; Jacquemart, A L
2000-08-01
Intra-specific chloroplast DNA (cpDNA) variation was studied in Sorbus aucuparia L., an entomophilous, mid-or early successional tree producing fleshy fruits. Eight PCR-amplified fragments of the chloroplast genome were screened for restriction fragment length polymorphisms, using one or two 4 bp-cutter restriction endonucleases. cpDNA variation was investigated on two geographical scales: (1) among four regions in France and Belgium; and (2) within the Belgian region. A total of 150 individuals from six populations were analysed. Fourteen polymorphisms were detected in six of the cpDNA fragments. All polymorphisms probably resulted from insertions or deletions, and allowed the identification of 12 haplotypes. The level of genetic differentiation computed on the basis of haplotype frequencies was similar on the two geographical scales considered (G(STc) = 0.286 among regions, G(STc) = 0.259 among populations within the Belgian region). These values are much lower than those obtained in nine previously studied temperate tree species, which are all wind-pollinated, late-successional species producing dry fruits. These results might primarily be accounted for by the contrasting life history traits of S. aucuparia. In order to obtain insights into the relative contribution of pollen and seeds to gene flow, G(STc) was also compared with previously obtained G(ST) estimates based on allozyme data.
Groom, Kelly; Wang, Long; Simaan, Nabil; Netterville, James
2015-05-01
We expanded our prior work with transnasal robotic surgery (TNRS) in this study with the following aims: 1) use a cadaveric model to evaluate the feasibility of laryngoplasty with TNRS, 2) measure robot insertion times and forces, and 3) identify operational challenges to further guide the development of a flexible robotic system. Cadaveric study. A 5-mm robot was guided to the larynx via a transnasal approach. Insertion times and forces using TNRS and a 4-mm flexible fiberoptic laryngoscope (FFL) were measured. Target sites on the true vocal cords were marked, and the TNRS was telemanipulated to perform injection laryngoplasty. Insertion times averaged 5.05 seconds (range, 3.8-10.4 seconds) for the TNRS and 7.97 seconds (range, 6.2-11.6 seconds) for the FFL. Insertion forces averaged 2.06 newtons (range, 1.56-5.55 newtons) for the TNRS and 0.43 newtons (range, 0.157-1.138 newtons) for the FFL. The unpaired t test between times and forces revealed P values of .0024 and .0000658, respectively. Seven target injection sites on three vocal cords in two cadaveric larynxes were successfully injected. In two out of nine sites marked, we were unable to access the vocal cord due tongue base collapse that obscured the posterior airway. TNRS is able to effectively access the larynx, although in a supine model may be limited by tongue base collapse. Forces with TNRS were significantly higher than with the FFL, albeit within the same scale. Despite increased forces, there was no evidence of tissue trauma using TNRS. NA Laryngoscope, 125:1166-1168, 2015. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.
Anagnostakos, Konstantinos; Bachelier, Felix; Fürst, Oliver Alexander; Kelm, Jens
2006-05-01
We report three cases of anterior tibial tendon ruptures and the results of an anatomical study in regard to the tendon's insertion site and a literature review. Three patients were referred to our hospital with anterior tibial tendon ruptures. In the anatomical study, 53 feet were dissected, looking in particular for variants of the bony insertion of the tendon. Two patients had surgical treatment (one primary repair and one semimembranosus tendon graft) and one conservative treatment. After a mean followup of 14 weeks all patients had satisfactory outcomes. In the anatomical study, we noted three different insertion sites: in 36 feet the tendon inserted into the medial side of the cuneiform and the base of the first metatarsal bone and in 13 feet only into the medial side of the cuneiform bone. In the remaining four feet the tendon inserted into the cuneiform and the first metatarsal bone, but an additional tendon was noted taking its origin from the anterior tibial tendon near its insertion into the medial cuneiform and attaching to the proximal part of the first metatarsal. According to literature, surgical repair is the treatment of choice for acute ruptures and for patients with high activity levels. For chronic ruptures and patients with low demands, conservative management may lead to an equally good outcome. Knowledge of the anatomy in this region may be helpful for diagnosis and for the interpretation of intraoperative findings and choosing the most appropriate surgical procedure.
2014-01-01
Background Trichomonas vaginalis is the most prevalent non-viral sexually transmitted parasite. Although the protist is presumed to reproduce asexually, 60% of its haploid genome contains transposable elements (TEs), known contributors to genome variability. The availability of a draft genome sequence and our collection of >200 global isolates of T. vaginalis facilitate the study and analysis of TE population dynamics and their contribution to genomic variability in this protist. Results We present here a pilot study of a subset of class II Tc1/mariner TEs that belong to the T. vaginalis Tvmar1 family. We report the genetic structure of 19 Tvmar1 loci, their ability to encode a full-length transposase protein, and their insertion frequencies in 94 global isolates from seven regions of the world. While most of the Tvmar1 elements studied exhibited low insertion frequencies, two of the 19 loci (locus 1 and locus 9) show high insertion frequencies of 1.00 and 0.96, respectively. The genetic structuring of the global populations identified by principal component analysis (PCA) of the Tvmar1 loci is in general agreement with published data based on genotyping, showing that Tvmar1 polymorphisms are a robust indicator of T. vaginalis genetic history. Analysis of expression of 22 genes flanking 13 Tvmar1 loci indicated significantly altered expression of six of the genes next to five Tvmar1 insertions, suggesting that the insertions have functional implications for T. vaginalis gene expression. Conclusions Our study is the first in T. vaginalis to describe Tvmar1 population dynamics and its contribution to genetic variability of the parasite. We show that a majority of our studied Tvmar1 insertion loci exist at very low frequencies in the global population, and insertions are variable between geographical isolates. In addition, we observe that low frequency insertion is related to reduced or abolished expression of flanking genes. While low insertion frequencies might be expected, we identified two Tvmar1 insertion loci that are fixed across global populations. This observation indicates that Tvmar1 insertion may have differing impacts and fitness costs in the host genome and may play varying roles in the adaptive evolution of T. vaginalis. PMID:24834134
Unique haplotypes of cacao trees as revealed by trnH-psbA chloroplast DNA
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
Olszowski, Tomasz; Adler, Grażyna; Janiszewska-Olszowska, Joanna; Safranow, Krzysztof; Chlubek, Dariusz
2015-01-01
The aim of the study was to examine the frequencies of the genotypes and alleles of ACE insertion/deletion (I/D) polymorphism and their association with dental caries in a sample of Polish children. The study subjects were 120 children with dental caries experience (cases) and 41 caries-free individuals (controls). The genotyping was performed using polymerase chain reaction. The genotype distributions of ACE I/D polymorphism were not statistically different between carious and control children. However, we found a borderline overrepresentation of the II + ID genotypes versus the DD genotype in the carious compared to the control group (69.2% and 51.2%, respectively, p = 0.057). Logistic regression analysis adjusted for age and sex revealed that I allele carriage was a significant predictor of dental caries susceptibility (OR = 2.14, 95% CI = 1.02-4.49, p = 0.041). In conclusion, the DD genotype of ACE I/D polymorphism might be protective against dental caries in Polish children. © 2015 S. Karger AG, Basel.
Lim, Kwang-il; Klimczak, Ryan; Yu, Julie H.; Schaffer, David V.
2010-01-01
Retroviral vectors offer benefits of efficient delivery and stable gene expression; however, their clinical use raises the concerns of insertional mutagenesis and potential oncogenesis due to genomic integration preferences in transcriptional start sites (TSS). We have shifted the integration preferences of retroviral vectors by generating a library of viral variants with a DNA-binding domain inserted at random positions throughout murine leukemia virus Gag-Pol, then selecting for variants that are viable and exhibit altered integration properties. We found seven permissive zinc finger domain (ZFD) insertion sites throughout Gag-Pol, including within p12, reverse transcriptase, and integrase. Comprehensive genome integration analysis showed that several ZFD insertions yielded retroviral vector variants with shifted integration patterns that did not favor TSS. Furthermore, integration site analysis revealed selective integration for numerous mutants. For example, two retroviral variants with a given ZFD at appropriate positions in Gag-Pol strikingly integrated primarily into four common sites out of 3.1 × 109 possible human genome locations (P = 4.6 × 10-29). Our findings demonstrate that insertion of DNA-binding motifs into multiple locations in Gag-Pol can make considerable progress toward engineering safer retroviral vectors that integrate into a significantly narrowed pool of sites on human genome and overcome the preference for TSS. PMID:20616052
Murat, M; Aekeper, A; Yuan, L Y; Alim, T; Du, G J; Abdusamat, A; Wu, G W; Aniwer, Y
2015-10-29
Here, we have investigated the correlation between calcium oxalate stone formation and Fn gene polymorphisms in urinary calculi patients among the Uighur population (Xinjiang region). In this case control study, genomic DNA extracted from the peripheral blood of 129 patients with calcium oxalate stones (patient group) and 94 normal people (control group) was used to genotype polymorphisms in the rs6725958, rs10202709, and rs35343655 sites of the Fn gene by polymerase chain reaction-restriction fragment length polymorphism. Subsequently, the association between different genotypes and susceptibility to calcium oxalate stone formation was compared among the patient and control groups. Single nucleotide polymorphisms (SNPs) were detected in the rs6725958, rs10202709, and rs35343655 sites of the Fn gene among the patient and control groups. The genotype distributions of the three loci complied with the Hardy-Weinberg equilibrium. The results of allele frequencies of the patient/control group for polymorphisms in the rs6725958 site of the Fn gene were C = 179 (69.92%)/119 (63.30%) and A = 77 (30.08%)/69 (36.70%), in the rs10202709 site were C = 245 (95.70%)/176 (93.63%) and T = 11 (4.30%)/12 (6.38%), and in the rs35343655 site of the Fn gene were A = 139 (54.30%)/87 (46.28%) and G = 117 (45.70%)/101 (53.72%). We observed no significant differences between the three SNPs and development of calcium oxalate stones. Polymorphisms in rs6725958, rs10202709, and rs35343655 of the Fn gene had no obvious effect on the susceptibility to the development of calcium oxalate stones in the Uighur population, residing in the Xinjiang region of China.
Schoville, Sean D.; Flowers, Jonathan M.; Burton, Ronald S.
2012-01-01
The marine copepod Tigriopus californicus lives in intertidal rock pools along the Pacific coast, where it exhibits strong, temporally stable population genetic structure. Previous allozyme surveys have found high frequency private alleles among neighboring subpopulations, indicating that there is limited genetic exchange between populations. Here we evaluate the factors responsible for the diversification and maintenance of alleles at the phosphoglucose isomerase (Pgi) locus by evaluating patterns of nucleotide variation underlying previously identified allozyme polymorphism. Copepods were sampled from eleven sites throughout California and Baja California, revealing deep genetic structure among populations as well as genetic variability within populations. Evidence of recombination is limited to the sample from Pescadero and there is no support for linkage disequilibrium across the Pgi locus. Neutrality tests and codon-based models of substitution suggest the action of natural selection due to elevated non-synonymous substitutions at a small number of sites in Pgi. Two sites are identified as the charge-changing residues underlying allozyme polymorphisms in T. californicus. A reanalysis of allozyme variation at several focal populations, spanning a period of 26 years and over 200 generations, shows that Pgi alleles are maintained without notable frequency changes. Our data suggest that diversifying selection accounted for the origin of Pgi allozymes, while McDonald-Kreitman tests and the temporal stability of private allozyme alleles suggests that balancing selection may be involved in the maintenance of amino acid polymorphisms within populations. PMID:22768211
Association of insertion-deletions polymorphisms with colorectal cancer risk and clinical features.
Marques, Diego; Ferreira-Costa, Layse Raynara; Ferreira-Costa, Lorenna Larissa; Correa, Romualdo da Silva; Borges, Aline Maciel Pinheiro; Ito, Fernanda Ribeiro; Ramos, Carlos Cesar de Oliveira; Bortolin, Raul Hernandes; Luchessi, André Ducati; Ribeiro-Dos-Santos, Ândrea; Santos, Sidney; Silbiger, Vivian Nogueira
2017-10-07
To investigate the association between 16 insertion-deletions (INDEL) polymorphisms, colorectal cancer (CRC) risk and clinical features in an admixed population. One hundred and forty patients with CRC and 140 cancer-free subjects were examined. Genomic DNA was extracted from peripheral blood samples. Polymorphisms and genomic ancestry distribution were assayed by Multiplex-PCR reaction, separated by capillary electrophoresis on the ABI 3130 Genetic Analyzer instrument and analyzed on GeneMapper ID v3.2. Clinicopathological data were obtained by consulting the patients' clinical charts, intra-operative documentation, and pathology scoring. Logistic regression analysis showed that polymorphism variations in IL4 gene was associated with increased CRC risk, while TYMS and UCP2 genes were associated with decreased risk. Reference to anatomical localization of tumor Del allele of NFKB1 and CASP8 were associated with more colon related incidents than rectosigmoid. In relation to the INDEL association with tumor node metastasis (TNM) stage risk, the Ins alleles of ACE , HLAG and TP53 (6 bp INDEL) were associated with higher TNM stage. Furthermore, regarding INDEL association with relapse risk, the Ins alleles of ACE , HLAG , and UGT1A1 were associated with early relapse risk, as well as the Del allele of TYMS . Regarding INDEL association with death risk before 10 years, the Ins allele of SGSM3 and UGT1A1 were associated with death risk. The INDEL variations in ACE , UCP2 , TYMS , IL4 , NFKB1 , CASP8 , TP53 , HLAG , UGT1A1 , and SGSM3 were associated with CRC risk and clinical features in an admixed population. These data suggest that this cancer panel might be useful as a complementary tool for better clinical management, and more studies need to be conducted to confirm these findings.
Fisher, Colleen A.; Bhattarai, Eric K.; Osterstock, Jason B.; Dowd, Scot E.; Seabury, Paul M.; Vikram, Meenu; Whitlock, Robert H.; Schukken, Ynte H.; Schnabel, Robert D.; Taylor, Jeremy F.; Womack, James E.; Seabury, Christopher M.
2011-01-01
Members of the Toll-like receptor (TLR) gene family occupy key roles in the mammalian innate immune system by functioning as sentries for the detection of invading pathogens, thereafter provoking host innate immune responses. We utilized a custom next-generation sequencing approach and allele-specific genotyping assays to detect and validate 280 biallelic variants across all 10 bovine TLR genes, including 71 nonsynonymous single nucleotide polymorphisms (SNPs) and one putative nonsense SNP. Bayesian haplotype reconstructions and median joining networks revealed haplotype sharing between Bos taurus taurus and Bos taurus indicus breeds at every locus, and specialized beef and dairy breeds could not be differentiated despite an average polymorphism density of 1 marker/158 bp. Collectively, 160 tagSNPs and two tag insertion-deletion mutations (indels) were sufficient to predict 100% of the variation at 280 variable sites for both Bos subspecies and their hybrids, whereas 118 tagSNPs and 1 tagIndel predictively captured 100% of the variation at 235 variable sites for B. t. taurus. Polyphen and SIFT analyses of amino acid (AA) replacements encoded by bovine TLR SNPs indicated that up to 32% of the AA substitutions were expected to impact protein function. Classical and newly developed tests of diversity provide strong support for balancing selection operating on TLR3 and TLR8, and purifying selection acting on TLR10. An investigation of the persistence and continuity of linkage disequilibrium (r2≥0.50) between adjacent variable sites also supported the presence of selection acting on TLR3 and TLR8. A case-control study employing validated variants from bovine TLR genes recognizing bacterial ligands revealed six SNPs potentially eliciting small effects on susceptibility to Mycobacterium avium spp paratuberculosis infection in dairy cattle. The results of this study will broadly impact domestic cattle research by providing the necessary foundation to explore several avenues of bovine translational genomics, and the potential for marker-assisted vaccination. PMID:22164200
Dunn, R. C.; Laurie, C. C.
1995-01-01
Variation in the DNA sequence and level of alcohol dehydrogenase (Adh) gene expression in Drosophila melanogaster have been studied to determine what types of DNA polymorphisms contribute to phenotypic variation in natural populations. The Adh gene, like many others, shows a high level of variability in both DNA sequence and quantitative level of expression. A number of transposable element insertions occur in the Adh region and one of these, a copia insertion in the 5' flanking region, is associated with unusually low Adh expression. To determine whether this insertion (called RI42) causes the low expression level, the insertion was excised from the cloned RI42 Adh gene and the effect was assessed by P-element transformation. Removal of this insertion causes a threefold increase in the level of ADH, clearly showing that it contributes to the naturally occurring variation in expression at this locus. Removal of all but one LTR also causes a threefold increase, indicating that the mechanism is not a simple sequence disruption. Furthermore, this copia insertion, which is located between the two Adh promoters and their upstream enhancer sequences, has differential effects on the levels of proximal and distal transcripts. Finally, a test for the possible modifying effects of two suppressor loci, su(w(a)) and su(f), on this insertional mutation was negative, in contrast to a previous report in the literature. PMID:7498745
Liu, San-Xu; Hou, Wei; Zhang, Xue-Yan; Peng, Chang-Jun; Yue, Bi-Song; Fan, Zhen-Xin; Li, Jing
2018-07-18
The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature (IUCN). Short tandem repeats (STRs) refer to repetitive elements of genome sequence that range in length from 1-6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software (lobSTR), we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals (P<0.05, t-test). We also found a greater number of homozygous STRs than heterozygous STRs (P<0.05, t-test), with the Emei and Jianyang Tibetan macaques showing more heterozygous loci than Huangshan Tibetan macaques. The proportion of insertions and mean variation of alleles in the Emei and Jianyang individuals were slightly higher than those in the Huangshan individuals, thus revealing differences in STR allele size between the two populations. The polymorphic STR loci identified based on the reference genome showed good amplification efficiency and could be used to study population genetics in Tibetan macaques. The neighbor-joining tree classified the five macaques into two different branches according to their geographical origin, indicating high genetic differentiation between the Huangshan and Sichuan populations. We elucidated the distribution characteristics of STRs in the Tibetan macaque genome and provided an effective method for screening polymorphic STRs. Our results also lay a foundation for future genetic variation studies of macaques.
Miranda, Raquel C K; Genro, Júlia P; Campagnolo, Paula D B; Mattevi, Vanessa S; Vitolo, Márcia R; Almeida, Silvana
2017-05-01
The 5-HTT gene contains polymorphisms in its promoter region, the insertion/deletion (5-HTTLPR) that creates long (L) or short (S) alleles (biallelic approach) and SNP (rs25531) in L allele (triallelic approach). The aim of this study is to investigate the association of the 5-HTTLPR and rs25531 polymorphisms, using bi- and triallelic approach, with dietary intake and anthropometric parameters in children followed until 8 years old. The sample were 303 children who were recruited at birth and examined at 1, 3 to 4 and 7 to 8 years old. The polymorphisms were analyzed by polymerase-chain-reaction-based methods. In the biallelic approach, children with the S/S genotype presented a higher body mass index Z-score in the three developmental stages and higher sum of skinfolds at 3 to 4 and 7 to 8 years old than carriers of the L allele. In the triallelic approach, S/S, Lg/S plus Lg/Lg genotypes were associated with higher energy intake daily at 1 year old and with waist circumference at 3 to 4 years old. In the biallelic approach, the 5-HTTLPR polymorphism is associated with food intake, body mass index Z-score and sum of skinfolds in children, reinforcing the role of the serotonin transporter in childhood obesity. Our data indicate that the biallelic approach is more sensible than the triallelic approach for detected associations with food intake and nutritional status in childhood. Identifying susceptibility genes in early life could provide the foundations for interventions in lifestyle to prevent children to become obese adults. Copyright © 2017. Published by Elsevier Inc.
Karahan, Zulkuf; Ugurlu, Murat; Ucaman, Berzal; Veysel Ulug, Ali; Kaya, Ilyas; Cevik, Kemal; Sahin Adiyaman, Mehmet; Oztürk, Onder; Iyem, Hikmet; Ozdemir, Ferit
2016-01-01
Angiotensin converting enzyme (ACE) gene polymorphism is associated with high renin-angiotensin system causing myocardial fibrosis and ventricular repolarization abnormality. Based on these findings, this study was designed to determine the association between ACE gene insertion/deletion (I/D) polymorphism and QT dispersion after acute myocardial infarction (MI). The study included 108 patients with acute MI. Blood samples were obtained from all the patients for genomic DNA analysis. ECGs were recorded at baseline and at the end of a 6-month follow up. The OT dispersion was manually calculated. The mean age of the patients was 57.5 ±9.9 years (ranging from 36 to 70). The patients with DD genotype showed longer QT dispersion than patients with II or DI genotype at the baseline, while at the end of the six-month follow up the patients with DI genotype showed longer QT dispersion than patients with DD or II genotypes. However, the magnitude of the QT dispersion prolongation was higher in patients carrying the ACE D allele than patients who were not carrying it, at baseline and at the end of six-month follow up (52.5 ±2.6 msn vs. 47.5±2.1 msn at baseline, 57±3.2 msn vs. 53±2.6 msn in months, P: 0.428 and P: 0.613, respectively). Carriers of the D allele of ACE gene I/D polymorphism may be associated with QT dispersion prolongation in patients with MI.An interaction of QT dispersion and ACE gene polymorphism may be associated with an elevation of serum type I-C terminal pro-collagen concentration, possibly leading to myocardial fibrosis, and increased action potential duration.
Çarkaxhiu Bulut, Gresa; Rodopman Arman, Ayşe; Güney, İlter; Gültepe, Pınar
2017-09-01
More than one-fourth adolescents are exposed to unexpected frightening experiences and traumas until adulthood. In this study, we aimed to determine the potential role of serotonin transporter (5-HTT) gene polymorphism regarding resilience factors in the symptom variability of individuals exposed to sexual abuse. Adolescents aged 11-17 years, who were admitted to the Marmara University Child Psychiatry Outpatient Clinic Forensic division with sexual abuse experience history, were informed about the research, and volunteers were included in the study. Turkish versions of "Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime (K-SADS-PL)" was used to assess the psychopathology and functionality. The evaluation of participants also included self-reports based on "Eysenck Personality Inventory" and "Ways of Coping Inventory" for reflecting the resilience domain. The sample included 16 girls (88.9%) and 2 boys (11.1%), and the mean (±standard deviation) age was 14.58±1.97 years. Genotyping of the insertion/deletion polymorphism (5-HTTLPR) in the 5-HTT gene's transcriptional control zone was established, and 8 participants (44.4%) were determined to be of the LL genotype, while 7 (38.8%) were LS and 3 (16.6%) were SS carriers. Considering the relationship between coping styles regarding resilience and genetic variants, 87.5% of participants (n=7) exhibiting problem-focused coping style were determined found to carry the LL allele, while 90% (n=9) who exhibited emotion-focused coping styles were the SS-LS allele carriers (p=0.003). Our findings suggest that 5-HTTLPR gene polymorphism has a significant impact on the formation of coping styles. More studies are needed to determine other factors involved in the complex relationship between 5-HTTLPR gene polymorphism and development of psychopathology.
Stepwise Loop Insertion Strategy for Active Site Remodeling to Generate Novel Enzyme Functions.
Hoque, Md Anarul; Zhang, Yong; Chen, Liuqing; Yang, Guangyu; Khatun, Mst Afroza; Chen, Haifeng; Hao, Liu; Feng, Yan
2017-05-19
The remodeling of active sites to generate novel biocatalysts is an attractive and challenging task. We developed a stepwise loop insertion strategy (StLois), in which randomized residue pairs are inserted into active site loops. The phosphotriesterase-like lactonase from Geobacillus kaustophilus (GkaP-PLL) was used to investigate StLois's potential for changing enzyme function. By inserting six residues into active site loop 7, the best variant ML7-B6 demonstrated a 16-fold further increase in catalytic efficiency toward ethyl-paraoxon compared with its initial template, that is a 609-fold higher, >10 7 fold substrate specificity shift relative to that of wild-type lactonase. The remodeled variants displayed 760-fold greater organophosphate hydrolysis activity toward the organophosphates parathion, diazinon, and chlorpyrifos. Structure and docking computations support the source of notably inverted enzyme specificity. Considering the fundamental importance of active site loops, the strategy has potential for the rapid generation of novel enzyme functions by loop remodeling.
Gladyshev, Eugene A; Arkhipova, Irina R
2009-12-15
Ribosomal DNA genes in many eukaryotes contain insertions of non-LTR retrotransposable elements belonging to the R2 clade. These elements persist in the host genomes by inserting site-specifically into multicopy target sites, thereby avoiding random disruption of single-copy host genes. Here we describe R9 retrotransposons from the R2 clade in the 28S RNA genes of bdelloid rotifers, small freshwater invertebrate animals best known for their long-term asexuality and for their ability to survive repeated cycles of desiccation and rehydration. While the structural organization of R9 elements is highly similar to that of other members of the R2 clade, they are characterized by two distinct features: site-specific insertion into a previously unreported target sequence within the 28S gene, and an unusually long target site duplication of 126 bp. We discuss the implications of these findings in the context of bdelloid genome organization and the mechanisms of target-primed reverse transcription.
Zhang, Yu-Dang; Shen, Chun-Mei; Jin, Rui; Li, Ya-Ni; Wang, Bo; Ma, Li-Xia; Meng, Hao-Tian; Yan, Jiang-Wei; Dan Wang, Hong-; Yang, Ze-Long; Zhu, Bo-Feng
2015-05-01
Insertion/deletion polymorphisms have become a research hot spot in forensic science due to their tremendous potential in recent years. In the present study, we investigated 30 indel loci in a Chinese Yi ethnic group. The allele frequencies of the short allele of the 30 indel loci were in the range of 0.1025-0.9221. The power of discrimination values were observed ranging from to 0.2630 (HLD111 locus) to 0.6607 (HLD70 locus) and probability of exclusion values ranged from 0.0189 (HLD111 locus) to 0.2343 (HLD56 locus). The combined power of discrimination and power of exclusion for 30 loci in the studied Yi group were 0.99999999995713 and 0.97746, respectively, which showed tremendous potential for forensic personal identification in the Yi group. Moreover, the DA distances, phylogenetic tree, principal component analysis, and cluster analysis showed the Yi group had close genetic relationships with the Tibetan, South Korean, Chinese Han, and She groups. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Gard, Paul R
2010-01-01
This review considers the 250+ papers concerning the association of the angiotensin converting enzyme (ACE) gene insertion/deletion polymorphism (rs1799752) and various disease conditions published in 2009. The deletion allele occurs in approximately 55% of the population and is associated with increased activity of the ACE enzyme. It might be predicted that the D allele, therefore, might be associated with pathologies involving increased activity of the renin-angiotensin system. The D allele was seen to be associated with an increased risk of hypertension, pre-eclampsia, heart failure, cerebral infarct, diabetic nephropathy, encephalopathy, asthma, severe hypoglycaemia in diabetes, gastric cancer (in Caucasians) and poor prognosis following kidney transplant. On the positive side, the D allele appears to offer protection against schizophrenia and chronic periodontitis and confers greater up-per-body strength in old age. The I allele, meanwhile, offers improved endurance/athletic performance and aerobic capacity as determined by lung function tests, although it does increase the risk of oral squamous cell carcinoma and obstructive sleep apnoea in hypertensives. PMID:21537387
Transposon based functional characterization of soybean genes
USDA-ARS?s Scientific Manuscript database
Type II transposable elements that use cut and paste mechanism for jumping from one genomic region to another is ideal in tagging and cloning genes. Precise excision from an insertion site in a mutant gene leads to regaining the wild-type function. Thus, function of a gene can be established based o...
Zhang, Ruixing; Wang, Rui; Zhang, Fengbin; Wu, Chensi; Fan, Haiyan; Li, Yan; Wang, Cuiju; Guo, Zhanjun
2010-11-26
Accumulation of single nucleotide polymorphisms (SNPs) in the displacement loop (D-loop) of mitochondrial DNA (mtDNA) has been described for different types of cancers and might be associated with cancer risk and disease outcome. We used a population-based series of esophageal squamous cell carcinoma (ESCC) patients for investigating the prediction power of SNPs in mitochondrial D-loop. The D-loop region of mtDNA was sequenced for 60 ESCC patients recorded in the Fourth Hospital of Hebei Medical University between 2003 and 2004. The 5 year survival curve were calculated with the Kaplan-Meier method and compared by the log-rank test at each SNP site, a multivariate survival analysis was also performed with the Cox proportional hazards method. The SNP sites of nucleotides 16274G/A, 16278C/T and 16399A/G were identified for prediction of post-operational survival by the log-rank test. In an overall multivariate analysis, the 16278 and 16399 alleles were identified as independent predictors of ESCC outcome. The length of survival of patients with the minor allele 16278T genotype was significantly shorter than that of patients with 16278C at the 16278 site (relative risk, 3.001; 95% CI, 1.029 - 8.756; p = 0.044). The length of survival of patients with the minor allele 16399G genotype was significantly shorter than that of patients with the more frequent allele 16399A at the 16399 site in ESCC patients (relative risk, 3.483; 95% CI, 1.068 - 11.359; p = 0.039). Genetic polymorphisms in the D-loop are independent prognostic markers for patients with ESCC. Accordingly, the analysis of genetic polymorphisms in the mitochondrial D-loop can help identify patient subgroups at high risk of a poor disease outcome.
Miller, Jena L; Block-Abraham, Dana M; Blakemore, Karin J; Baschat, Ahmet A
2018-06-06
The insertion site of the fetoscope for laser occlusion (FLOC) treatment of twin-twin transfusion syndrome (TTTS) determines the likelihood of treatment success. We assessed a standardized preoperative ultrasound approach for its ability to identify critical landmarks for successful FLOC. Three surgeons independently performed preoperative ultrasound and deduced the likely orientation of the intertwin membrane (ITM) and vascular equator (VE) based on the sites of the cord insertion, the lie of the donor, and the size discordance between twins. At FLOC, these landmarks were visually verified and compared to preoperative assessments. Fifty consecutive FLOC surgeries had 127 preoperative assessments. Basic ITM and VE orientation were accurately predicted in 115 (90.6%), 109 (85.8%), and 105 (82.7%) assessments. Predictions were anatomically correct in 96 (75.6%), 70 (55.1%), and 58 (45.7%) assessments with no differences in accuracy between operators of different training level. The ITM/VE relationship was most poorly predicted in stage-3 TTTS (χ2, p = 0.016). In TTTS, preoperative ultrasound identification of placental cord insertion sites, lie of the donor twin, and size discordance enables preoperative prediction of key landmarks for successful FLOC. © 2018 S. Karger AG, Basel.
Kato, Hirokazu; Kondo, Motoharu; Imada, Hajime; Kuroda, Masahiro; Kamimura, Yoshitsugu; Saito, Kazuyuki; Kuroda, Kagayaki; Ito, Koichi; Takahashi, Hideaki; Matsuki, Hidetoshi
2013-05-01
This article is a redissemination of the previous Japanese Quality Assurance Guide guidelines. Specific absorption rate and temperature distribution were investigated with respect to various aspects including metallic implant size and shape, insertion site, insertion direction, blood flow and heating power, and simulated results were compared with adverse reactions of patients treated by radio frequency capacitive-type heating. Recommended guidelines for safe heating methods for patients with metallic implants are presented based on our findings.
Hemlock woolly adelgid (Homoptera: Adelgidae): stylet bundle insertion and feeding sites
Rebecca F. Young; Kathleen S. Shields; Graeme P. Berlyn
1995-01-01
Stylet bundle insertion site, path traveled, and feeding site were examined for the hemlock woolly adelgid, Adelges tsugae Annand, on needles from current and previous years of eastern hemlock, Tsuga canadensis Carriere. The stylet bundle is composed of 4 individual stylets--2 outer mandibular stylets and 2 inner maxillary stylets...
Suruga, Makoto; Horaguchi, Takashi; Iriuchishima, Takanori; Yahagi, Yoshiyuki; Iwama, Genki; Tokuhashi, Yasuaki; Aizawa, Shin
2017-08-01
The purpose of this study was to evaluate the detailed anatomy of the femoral anterior cruciate ligament (ACL) insertion site, with special attention given to the morphology of the mid-substance insertion areas and the fan-like extension fibers. Twenty-three non-paired human cadaver knees were used (7 Males, 16 Females, median age 83, range 69-96). All soft tissues around the knee were resected except the ligaments. The ACL was divided into antero-medial (AM) and postero-lateral (PL) bundles according to the difference in macroscopic tension patterns. The ACL was carefully dissected and two outlines were made of the periphery of each bundle insertion site: those which included and those which excluded the fan-like extension fibers. An accurate lateral view of the femoral condyle was photographed with a digital camera, and the images were downloaded to a personal computer. The area of each bundle, including and excluding the fan-like extension fibers, was measured with Image J software (National Institution of Health). The width and length of the mid-substance insertion sites were also evaluated using same image. The femoral ACL footprint was divided into four regions (mid-substance insertion sites of the AM and PL bundles, and fan-like extensions of the AM and PL bundles). The measured areas of the mid-substance insertion sites of the AM and PL bundles were 35.5 ± 12.5, and 32.4 ± 13.8 mm 2 , respectively. Whole width and length of the mid-substance insertion sites were 5.3 ± 1.4, and 15.5 ± 2.9 mm, respectively. The measured areas of the fan-like extensions of the AM and PL bundles were 27 ± 11.5, and 29.5 ± 12.4 mm 2 , respectively. The femoral ACL footprint was divided into quarters of approximately equal size (mid-substance insertion sites of the AM and PL bundles, and fan-like extensions of the AM and PL bundles). For clinical relevance, to perform highly reproducible anatomical ACL reconstruction, the presence of the fan-like extension fibers should be taken into consideration.
The novel fusion transcript NR5A2-KLHL29FT is generated by an insertion at the KLHL29 locus.
Sun, Zhenguo; Ke, Xiquan; Salzberg, Steven L; Kim, Daehwan; Antonescu, Valentin; Cheng, Yulan; Huang, Binbin; Song, Jee Hoon; Abraham, John M; Ibrahim, Sariat; Tian, Hui; Meltzer, Stephen J
2017-05-01
Novel fusion transcripts (FTs) caused by chromosomal rearrangement are common factors in the development of cancers. In the current study, the authors used massively parallel RNA sequencing to identify new FTs in colon cancers. RNA sequencing (RNA-Seq) and TopHat-Fusion were used to identify new FTs in colon cancers. The authors then investigated whether the novel FT nuclear receptor subfamily 5, group A, member 2 (NR5A2)-Kelch-like family member 29 FT (KLHL29FT) was transcribed from a genomic chromosomal rearrangement. Next, the expression of NR5A2-KLHL29FT was measured by quantitative real-time polymerase chain reaction in colon cancers and matched corresponding normal epithelia. The authors identified the FT NR5A2-KLHL29FT in normal and cancerous epithelia. While investigating this transcript, it was unexpectedly found that it was due to an uncharacterized polymorphic germline insertion of the NR5A2 sequence from chromosome 1 into the KLHL29 locus at chromosome 2, rather than a chromosomal rearrangement. This germline insertion, which occurred at a population frequency of 0.40, appeared to bear no relationship to cancer development. Moreover, expression of NR5A2-KLHL29FT was validated in RNA specimens from samples with insertions of NR5A2 at the KLHL29 gene locus, but not from samples without this insertion. It is interesting to note that NR5A2-KLH29FT expression levels were significantly lower in colon cancers than in matched normal colonic epithelia (P =.029), suggesting the potential participation of NR5A2-KLHL29FT in the origin or progression of this tumor type. NR5A2-KLHL29FT was generated from a polymorphism insertion of the NR5A2 sequence into the KLHL29 locus. NR5A2-KLHL29FT may influence the origin or progression of colon cancer. Moreover, researchers should be aware that similar FTs may occur due to transchromosomal insertions that are not correctly annotated in genome databases, especially with current assembly algorithms. Cancer 2017;123:1507-1515. © 2017 American Cancer Society. © 2016 American Cancer Society.
Burstyn, J N; Heiger-Bernays, W J; Cohen, S M; Lippard, S J
2000-11-01
Mapping of cis-diamminedichloroplatinum(II) (cis-DDP, cisplatin) DNA adducts over >3000 nucleotides was carried out using a replication blockage assay. The sites of inhibition of modified T4 DNA polymerase, also referred to as stop sites, were analyzed to determine the effects of local sequence context on the distribution of intrastrand cisplatin cross-links. In a 3120 base fragment from replicative form M13mp18 DNA containing 24.6% guanine, 25.5% thymine, 26.9% adenine and 23.0% cytosine, 166 individual stop sites were observed at a bound platinum/nucleotide ratio of 1-2 per thousand. The majority of stop sites (90%) occurred at G(n>2) sequences and the remainder were located at sites containing an AG dinucleotide. For all of the GG sites present in the mapped sequences, including those with Gn(>)2, 89% blocked replication, whereas for the AG sites only 17% blocked replication. These blockage sites were independent of flanking nucleotides in a sequence of N(1)G*G*N(2) where N(1), N(2) = A, C, G, T and G*G* indicates a 1,2-intrastrand platinum cross-link. The absence of long-range sequence dependence was confirmed by monitoring the reaction of cisplatin with a plasmid containing an 800 bp insert of the human telomere repeat sequence (TTAGGG)(n). Platination reactions monitored at several formal platinum/nucleotide ratios or as a function of time reveal that the telomere insert was not preferentially damaged by cisplatin. Both replication blockage and telomere-insert plasmid platination experiments indicate that cisplatin 1,2-intrastrand adducts do not form preferentially at G-rich sequences in vitro.
Topology of the membrane protein LamB by epitope tagging and a comparison with the X-ray model.
Newton, S M; Klebba, P E; Michel, V; Hofnung, M; Charbit, A
1996-06-01
We previously developed a genetic approach to study, with a single antibody, the topology of the outer membrane protein LamB, an Escherichia coli porin with specificity towards maltodextrins and a receptor for bacteriophage lambda. Our initial procedure consisted of inserting at random the same reporter epitope (the C3 neutralization epitope from poliovirus) into permissive sites of LamB (i.e., sites which tolerate insertions without deleterious effects on the protein activities or the cell). A specific monoclonal antibody was then used to examine the position of the inserted epitope with respect to the protein and the membrane. In the present work, we set up a site-directed procedure to insert the C3 epitope at new sites in order to distinguish between two-dimensional folding models. This allowed us to identify two new surface loops of LamB and to predict another periplasmic exposed region. The results obtained by random and directed epitope tagging are analyzed in light of the recently published X-ray structure of the LamB protein. Study of 23 hybrid LamB-C3 proteins led to the direct identification of five of the nine external loops (L4, L5, L6, L7, and L9) and led to the prediction of four periplasmic loops (I1, I4, I5, and I8) of LamB. Nine of the hybrid proteins did not lead to topological conclusions, and none led to the wrong predictions or conclusions. The comparison indicates that parts of models based on secondary structure predictions alone are not reliable and points to the importance of experimental data in the establishment of outer membrane protein topological models. The advantages and limitations of genetic foreign epitope insertion for the study of integral membrane proteins are discussed.
Strachan, Norval J C; Rotariu, Ovidiu; Lopes, Bruno; MacRae, Marion; Fairley, Susan; Laing, Chad; Gannon, Victor; Allison, Lesley J; Hanson, Mary F; Dallman, Tim; Ashton, Philip; Franz, Eelco; van Hoek, Angela H A M; French, Nigel P; George, Tessy; Biggs, Patrick J; Forbes, Ken J
2015-10-07
Genetic variation in an infectious disease pathogen can be driven by ecological niche dissimilarities arising from different host species and different geographical locations. Whole genome sequencing was used to compare E. coli O157 isolates from host reservoirs (cattle and sheep) from Scotland and to compare genetic variation of isolates (human, animal, environmental/food) obtained from Scotland, New Zealand, Netherlands, Canada and the USA. Nei's genetic distance calculated from core genome single nucleotide polymorphisms (SNPs) demonstrated that the animal isolates were from the same population. Investigation of the Shiga toxin bacteriophage and their insertion sites (SBI typing) revealed that cattle and sheep isolates had statistically indistinguishable rarefaction profiles, diversity and genotypes. In contrast, isolates from different countries exhibited significant differences in Nei's genetic distance and SBI typing. Hence, after successful international transmission, which has occurred on multiple occasions, local genetic variation occurs, resulting in a global patchwork of continental and trans-continental phylogeographic clades. These findings are important for three reasons: first, understanding transmission and evolution of infectious diseases associated with multiple host reservoirs and multi-geographic locations; second, highlighting the relevance of the sheep reservoir when considering farm based interventions; and third, improving our understanding of why human disease incidence varies across the world.
Schulze, Jenny Jakobsson; Lundmark, Jonas; Garle, Mats; Skilving, Ilona; Ekström, Lena; Rane, Anders
2008-07-01
Testosterone abuse is conventionally assessed by the urinary testosterone/epitestosterone (T/E) ratio, levels above 4.0 being considered suspicious. The large variation in testosterone glucuronide (TG) excretion and its strong association with a deletion polymorphism in the uridine diphospho-glucuronosyl transferase (UGT) 2B17 gene challenge the accuracy of the T/E ratio test. Our objective was to investigate whether genotype-based cutoff values will improve the sensitivity and specificity of the test. This was an open three-armed comparative study. A total of 55 healthy male volunteers with either two, one, or no allele [insertion/insertion, insertion/deletion, or deletion/deletion (del/del)] of the UGT2B17 gene was included in the study. A single im dose of 500 mg testosterone enanthate was administered. Urinary excretion of TG after dose and the T/E ratio during 15 d were calculated. The degree and rate of increase in the TG excretion rate were highly dependent on the UGT2B17 genotype with a 20-fold higher average maximum increase in the insertion/insertion group compared with the del/del group. Of the del/del subjects, 40% never reached the T/E ratio of 4.0 on any of the 15 d after the dose. When differentiated cutoff levels for the del/del (1.0) and the other genotypes (6.0) were applied, the sensitivity increased substantially for the del/del group, and false positives in the other genotypes were eliminated. Consideration of the genetic variation in disposition of androgens will improve the sensitivity and specificity of the testosterone doping test. This is of interest not only for combating androgen doping in sports, but also for detecting and preventing androgen abuse in society.
Liu, Shi; Gao, Peng; Zhu, Qianglong; Luan, Feishi; Davis, Angela R.; Wang, Xiaolu
2016-01-01
Cleaved amplified polymorphic sequence (CAPS) markers are useful tools for detecting single nucleotide polymorphisms (SNPs). This study detected and converted SNP sites into CAPS markers based on high-throughput re-sequencing data in watermelon, for linkage map construction and quantitative trait locus (QTL) analysis. Two inbred lines, Cream of Saskatchewan (COS) and LSW-177 had been re-sequenced and analyzed by Perl self-compiled script for CAPS marker development. 88.7% and 78.5% of the assembled sequences of the two parental materials could map to the reference watermelon genome, respectively. Comparative assembled genome data analysis provided 225,693 and 19,268 SNPs and indels between the two materials. 532 pairs of CAPS markers were designed with 16 restriction enzymes, among which 271 pairs of primers gave distinct bands of the expected length and polymorphic bands, via PCR and enzyme digestion, with a polymorphic rate of 50.94%. Using the new CAPS markers, an initial CAPS-based genetic linkage map was constructed with the F2 population, spanning 1836.51 cM with 11 linkage groups and 301 markers. 12 QTLs were detected related to fruit flesh color, length, width, shape index, and brix content. These newly CAPS markers will be a valuable resource for breeding programs and genetic studies of watermelon. PMID:27162496
Gu, Jun-dong; Hua, Feng; Mei, Chao-rong; Zheng, De-jie; Wang, Guo-fan; Zhou, Qing-hua
2014-01-01
Aim: Myeloperoxidase (MPO) and glutathione S-transferase pi 1 (GSTP1) are important carcinogen-metabolizing enzymes. The aim of this study was to investigate the association between the common polymorphisms of MPO and GSTP1 genes and lung cancer risk in Chinese Han population. Methods: A total of 266 subjects with lung cancer and 307 controls without personal history of the disease were recruited in this case control study. The tagSNPs approach was used to assess the common polymorphisms of MOP and GSTP1 genes and lung cancer risk according to the disequilibrium information from the HapMap project. The tagSNP rs7208693 was selected as the polymorphism site for MPO, while the haplotype-tagging SNPs rs1695, rs4891, rs762803 and rs749174 were selected as the polymorphism sites for GSTP1. The gene polymorphisms were confirmed using real-time PCR, cloning and sequencing. Results: The four GSTP1 haplotype-tagging SNPs rs1695, rs4891, rs762803 and rs749174, but not the MPO tagSNP rs7208693, exhibited an association with lung cancer susceptibility in smokers in the overall population and in the studied subgroups. When Phase 2 software was used to reconstruct the haplotype for GSTP1, the haplotype CACA (rs749174+rs1695 + rs762803+rs4891) exhibited an increased risk of lung cancer among smokers (adjust odds ratio 1.53; 95%CI 1.04–2.25, P=0.033). Furthermore, diplotype analyses demonstrated that the significant association between the risk haplotype and lung cancer. The risk haplotypes co-segregated with one or more biologically functional polymorphisms and corresponded to a recessive inheritance model. Conclusion: The common polymorphisms of the GSTP1 gene may be the candidates for SNP markers for lung cancer susceptibility in Chinese Han population. PMID:24786234
Moore, Desmond A.; Whatley, Zakiya N.; Joshi, Chandra P.; Osawa, Masaki
2016-01-01
ABSTRACT FtsZ, a bacterial tubulin homologue, is a cytoskeletal protein that assembles into protofilaments that are one subunit thick. These protofilaments assemble further to form a “Z ring” at the center of prokaryotic cells. The Z ring generates a constriction force on the inner membrane and also serves as a scaffold to recruit cell wall remodeling proteins for complete cell division in vivo. One model of the Z ring proposes that protofilaments associate via lateral bonds to form ribbons; however, lateral bonds are still only hypothetical. To explore potential lateral bonding sites, we probed the surface of Escherichia coli FtsZ by inserting either small peptides or whole fluorescent proteins (FPs). Among the four lateral surfaces on FtsZ protofilaments, we obtained inserts on the front and back surfaces that were functional for cell division. We concluded that these faces are not sites of essential interactions. Inserts at two sites, G124 and R174, located on the left and right surfaces, completely blocked function, and these sites were identified as possible sites for essential lateral interactions. However, the insert at R174 did not interfere with association of protofilaments into sheets and bundles in vitro. Another goal was to find a location within FtsZ that supported insertion of FP reporter proteins while allowing the FtsZ-FPs to function as the sole source of FtsZ. We discovered one internal site, G55-Q56, where several different FPs could be inserted without impairing function. These FtsZ-FPs may provide advances for imaging Z-ring structure by superresolution techniques. IMPORTANCE One model for the Z-ring structure proposes that protofilaments are assembled into ribbons by lateral bonds between FtsZ subunits. Our study excluded the involvement of the front and back faces of the protofilament in essential interactions in vivo but pointed to two potential lateral bond sites, on the right and left sides. We also identified an FtsZ loop where various fluorescent proteins could be inserted without blocking function; these FtsZ-FPs functioned as the sole source of FtsZ. This advance provides improved tools for all fluorescence imaging of the Z ring and may be especially important for superresolution imaging. PMID:27795325
Inter-seasonal maintenance of individual nest site preferences in hawksbill sea turtles.
Kamel, Stephanie J; Mrosovsky, N
2006-11-01
Within a single population of hawksbill sea turtles (Eretmochelys imbricata), we found a behavioral polymorphism for maternal nest site choice with respect to beach microhabitat characteristics. Some females preferred to nest in littoral forest and in places with overstory vegetation cover, and others preferred to nest in more open, deforested areas. Nest site choice was consistent within and between nesting seasons two years apart. This was not a result of females simply returning to the same location along the shoreline; beach sections used by individual turtles varied between seasons. Nest site choice was not influenced by changes in beach environment (e.g., beach width and foliage cover) or by changes in females' reproductive output (e.g., clutch size), suggesting that fidelity to particular microhabitats is a major determinant of the observed nesting patterns. Because hawksbills exhibit temperature-dependent sex determination, if the behavioral polymorphism in nest site choice has a genetic basis, as is plausible, then this would have implications for sex ratio evolution and offspring survival. By taking an individual-based approach to the study of maternal behavior we reveal previously overlooked individual variation and hope to provide some impetus for more detailed studies of nest site choice.
Jackson, Benjamin C.; Campos, José L.; Haddrill, Penelope R.; Charlesworth, Brian
2017-01-01
Four-fold degenerate coding sites form a major component of the genome, and are often used to make inferences about selection and demography, so that understanding their evolution is important. Despite previous efforts, many questions regarding the causes of base composition changes at these sites in Drosophila remain unanswered. To shed further light on this issue, we obtained a new whole-genome polymorphism data set from D. simulans. We analyzed samples from the putatively ancestral range of D. simulans, as well as an existing polymorphism data set from an African population of D. melanogaster. By using D. yakuba as an outgroup, we found clear evidence for selection on 4-fold sites along both lineages over a substantial period, with the intensity of selection increasing with GC content. Based on an explicit model of base composition evolution, we suggest that the observed AT-biased substitution pattern in both lineages is probably due to an ancestral reduction in selection intensity, and is unlikely to be the result of an increase in mutational bias towards AT alone. By using two polymorphism-based methods for estimating selection coefficients over different timescales, we show that the selection intensity on codon usage has been rather stable in D. simulans in the recent past, but the long-term estimates in D. melanogaster are much higher than the short-term ones, indicating a continuing decline in selection intensity, to such an extent that the short-term estimates suggest that selection is only active in the most GC-rich parts of the genome. Finally, we provide evidence for complex evolutionary patterns in the putatively neutral short introns, which cannot be explained by the standard GC-biased gene conversion model. These results reveal a dynamic picture of base composition evolution. PMID:28082609
Gómez-Pérez, Luis; Alfonso-Sánchez, Miguel A; Sánchez, Dora; García-Obregón, Susana; Espinosa, Ibone; Martínez-Jarreta, Begoña; De Pancorbo, Marian M; Peña, José A
2011-01-01
The Amazon basin is inhabited by some of the most isolated human groups worldwide. Among them, the Waorani tribe is one of the most interesting Native American populations from the anthropological perspective. This study reports a genetic characterization of the Waorani based on autosomal genetic loci. We analyzed 12 polymorphic Alu insertions in 36 Waorani individuals from different communal longhouses settled in the Yasuní National Park. The most notable finding was the strikingly reduced genetic diversity detected in the Waorani, corroborated by the existence of four monomorphic loci (ACE, APO, FXIIIB, and HS4.65), and of other four Alu markers that were very close to the fixation for the presence (PV92 and D1) or the absence (A25 and HS4.32) of the insertion. Furthermore, results of the centroid analysis supported the notion of the Waorani being one of the Amerindian groups less impacted by gene flow processes. The prolonged isolation of the Waorani community, in conjunction with a historically low effective population size and high inbreeding levels, have resulted in the drastic reduction of their genetic diversity, because of the effects of severe genetic drift. Recurrent population bottlenecks most likely determined by certain deep-rooted sociocultural practices of the Waorani (characterized by violence, internal quarrels, and revenge killings until recent times) are likely responsible for this pattern of diversity. The findings of this study illustrate how sociocultural factors can shape the gene pool of human populations. Copyright © 2011 Wiley-Liss, Inc.
Ingle, Elizabeth K. S.; Gilmartin, Philip M.
2015-01-01
Records of double-flowered Silene dioica date from the late sixteenth century and four named varieties are grown today, as previously, for their horticultural interest. Although double-flowered mutants have been characterized in several plants, their study in dioecious species is of particular interest due to influences of the homeotic mutation on the different floral whorl configurations in males and females. We have analysed four double-flowered varieties of Silene dioica: Flore Pleno and Rosea Plena date back to the seventeenth and nineteenth centuries, Thelma Kay and Firefly were recognized in the latter part of the twentieth and early twenty-first centuries. We have analysed the floral structure of the four varieties, which have distinct floral architectures. Based on Y chromosome-specific PCR analysis we show that Firefly is male and that the other three varieties are female: Random Amplification of Polymorphic DNA (RAPD) analyses suggested a common origin for the three female varieties. The double-flowered phenotype in all four varieties is caused by mutation of the C-function MADS-box transcription factor gene SDM1. We show that Firefly carries a unique 44bp insertion into SDM1, revealing an independent origin for this variety. Comparative analysis of SDM1 cDNA and genomic sequences in Flore Pleno, Rosea Plena and Thelma Kay shows that all three are caused by the same 7bp insertion within SDM1 and therefore share a common origin. The three alleles also differ by several single nucleotide polymorphisms, which represent somatic mutations accumulated over four centuries of asexual propagation. PMID:25878355
Shirasawa, Kenta; Hirakawa, Hideki; Nunome, Tsukasa; Tabata, Satoshi; Isobe, Sachiko
2016-01-01
Genome-wide mutations induced by ethyl methanesulfonate (EMS) and gamma irradiation in the tomato Micro-Tom genome were identified by a whole-genome shotgun sequencing analysis to estimate the spectrum and distribution of whole-genome DNA mutations and the frequency of deleterious mutations. A total of ~370 Gb of paired-end reads for four EMS-induced mutants and three gamma-ray-irradiated lines as well as a wild-type line were obtained by next-generation sequencing technology. Using bioinformatics analyses, we identified 5920 induced single nucleotide variations and insertion/deletion (indel) mutations. The predominant mutations in the EMS mutants were C/G to T/A transitions, while in the gamma-ray mutants, C/G to T/A transitions, A/T to T/A transversions, A/T to G/C transitions and deletion mutations were equally common. Biases in the base composition flanking mutations differed between the mutagenesis types. Regarding the effects of the mutations on gene function, >90% of the mutations were located in intergenic regions, and only 0.2% were deleterious. In addition, we detected 1,140,687 spontaneous single nucleotide polymorphisms and indel polymorphisms in wild-type Micro-Tom lines. We also found copy number variation, deletions and insertions of chromosomal segments in both the mutant and wild-type lines. The results provide helpful information not only for mutation research, but also for mutant screening methodology with reverse-genetic approaches. © 2015 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Magwire, Michael M; Bayer, Florian; Webster, Claire L; Cao, Chuan; Jiggins, Francis M
2011-10-01
To understand the molecular basis of how hosts evolve resistance to their parasites, we have investigated the genes that cause variation in the susceptibility of Drosophila melanogaster to viral infection. Using a host-specific pathogen of D. melanogaster called the sigma virus (Rhabdoviridae), we mapped a major-effect polymorphism to a region containing two paralogous genes called CHKov1 and CHKov2. In a panel of inbred fly lines, we found that a transposable element insertion in the protein coding sequence of CHKov1 is associated with increased resistance to infection. Previous research has shown that this insertion results in a truncated messenger RNA that encodes a far shorter protein than the susceptible allele. This resistant allele has rapidly increased in frequency under directional selection and is now the commonest form of the gene in natural populations. Using genetic mapping and site-specific recombination, we identified a third genotype with considerably greater resistance that is currently rare in the wild. In these flies there have been two duplications, resulting in three copies of both the truncated allele of CHKov1 and CHKov2 (one of which is also truncated). Remarkably, the truncated allele of CHKov1 has previously been found to confer resistance to organophosphate insecticides. As estimates of the age of this allele predate the use of insecticides, it is likely that this allele initially functioned as a defence against viruses and fortuitously "pre-adapted" flies to insecticides. These results demonstrate that strong selection by parasites for increased host resistance can result in major genetic changes and rapid shifts in allele frequencies; and, contrary to the prevailing view that resistance to pathogens can be a costly trait to evolve, the pleiotropic effects of these changes can have unexpected benefits.
Dai, Xiaofang; Liu, Zhao; Ren, Jinghua
2011-01-01
Recent studies have identified a negative correlation between serum levels of insulin-like growth factor binding protein-3 (IGFBP-3) and the risk of lung cancer. In this study, polymorphisms present at the −1590 site of the IGFBP-3 promoter were evaluated in relation to lung cancer risk in a Chinese Han population. A total of 248 nonsmall cell lung cancer (NSCLC) cases and 29 small cell lung cancer cases were compared with 252 matched, healthy controls. Polymerase chain reaction-based restriction fragment length polymorphism assays were used to detect polymorphisms present. The A/A genotype and an A allele were both associated with an increased risk of NSCLC after being adjusted for age and gender (adjusted odds ratio = 2.296, 95% confidence interval = 1.133–4.655; and adjusted odds ratio = 1.390, 95% confidence interval = 1.042–1.854, respectively). In conclusion, the A/A genotype and A allele of the IGFBP-3 promoter −1590 site may represent a genetic risk factor for NSCLC, with the A/A genotype being associated with a higher risk for squamous cell carcinoma than adenocarcinoma. PMID:21254935
Lauri, Andrea; Castiglioni, Bianca; Mariani, Paola
2011-07-01
Salmonella is a major cause of food-borne disease, and Salmonella enterica subspecies I includes the most clinically relevant serotypes. Salmonella serotype determination is important for the disease etiology assessment and contamination source tracking. This task will be facilitated by the disclosure of Salmonella serotype sequence polymorphisms, here annotated in seven genes (sefA, safA, safC, bigA, invA, fimA, and phsB) from 139 S. enterica strains, of which 109 belonging to 44 serotypes of subsp. I. One hundred nineteen polymorphic sites were scored and associated to single serotypes or to serotype groups belonging to S. enterica subsp. I. A diagnostic tool was constructed based on the Ligation Detection Reaction-Universal Array (LDR-UA) for the detection of polymorphic sites uniquely associated to serotypes of primary interest (Salmonella Hadar, Salmonella Infantis, Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Gallinarum, Salmonella Virchow, and Salmonella Paratyphi B). The implementation of promiscuous probes allowed the diagnosis of ten further serotypes that could be associated to a unique hybridization pattern. Finally, the sensitivity and applicability of the tool was tested on target DNA dilutions and with controlled meat contamination, allowing the detection of one Salmonella CFU in 25 g of meat.
Afanasiev, S A; Muslimova, E F; Rebrov, T Y; Sergienko, T N; Repin, A N
2016-09-01
to study relationship of ACE insertion-deletion (I/D) polymorphism and NOS3 T-786C polymorphism with characteristics of the course of ischemic heart disease (IHD) at the background of diabetes mellitus. Were examined 114 patients with IHD, 29.8% of patients had type 2 diabetes mellitus. ACE and NOS3 polymorphisms were determined by allele-specific polymerase chain reaction with primers by "Lytech". Patients with combined pathology belonged to older age group, had increased frequency of obesity and predominance of functional class II chronic heart failure. In this group we detected association of D allele of the ACE gene with higher frequency of dyslipidemia and obesity. Among patients with IHD without diabetes we observed associations of ACE I/D and NOS3 T-786C polymorphisms (close and moderate, respectively) with severity of effort angina. We also found that frequency of dyslipidemia among carriers of II and TT genotypes was lower than among carriers of other genotypes. Presence of type 2 diabetes as background pathology leads to a change of character of association of ACE I/D and NOS3 T-786C polymorphisms with clinical characteristics of patients with IHD.
Ha, Sung-Kyu
2014-01-01
Approximately 20–40% of diabetic patients develop nephropathy which is the leading cause of ESRD in developed countries. The ACE I/D polymorphism is thought to be a marker for functional polymorphism which regulates circulating and tissue ACE activity. While the initial study found a protective effect of the II genotype on the development of nephropathy in IDDM patients, subsequent studies have addressed the role of ACE I/D polymorphism in the development and progression of diabetic nephropathy. RAAS blockers are the first line drugs for the treatment hypertension associated with diabetes and have been widely used in everyday clinical practice for the purpose of reducing proteinuria in patients with various renal diseases. However, the antiproteinuric effect of RAAS blockers is variable and the percentage of reducing proteinuria is in the range of 20–80%. The antiproteinuric effect of RAAS blockers may be related to a number of factors: the type or the dose of RAAS blockers, the duration of therapy, the level of sodium intake, and the type of patient's ACE I/D genotype. Besides the nongenetic factors, drug responses, can be influenced by ACE gene polymorphism. In this review, we discuss the relationship between ACE I/D polymorphism and diabetic nephropathy and therapeutic response of RAAS blockers. PMID:25587546
Boronnikova, S V; Kalendar', R N
2010-01-01
Species-specific LTR retrotransposons were first cloned in five rare relic species of drug plants located in the Perm' region. Sequences of LTR retrotransposons were used for PCR analysis based on amplification of repeated sequences from LTR or other sites of retrotransposons (IRAP). Genetic diversity was studied in six populations of rare relic species of plants Adonis vernalis L. by means of the IRAP method; 125 polymorphic IRAP-markers were analyzed. Parameters for DNA polymorphism and genetic diversity of A. vernalis populations were determined.
Maurer-Stroh, Sebastian; Lee, Raphael T C; Gunalan, Vithiagaran; Eisenhaber, Frank
2013-05-01
A characteristic difference between highly and non-highly pathogenic avian influenza strains is the presence of an extended, often multibasic, cleavage motif insertion in the hemagglutinin protein. Such motif is found in H7N3 strains from chicken farm outbreaks in 2012 in Mexico. Through phylogenetic, sequence and structural analysis, we try to shed light on the role, prevalence, likelihood of appearance and origin of the inserted cleavage motifs in these H7N3 avian influenza strains. The H7N3 avian influenza strain which caused outbreaks in chicken farms in June/July 2012 in Mexico has a new extended cleavage site which is the likely reason for its high pathogenicity in these birds. This cleavage site appears to have been naturally acquired and was not present in the closest low pathogenic precursors. Structural modeling shows that insertion of a productive cleavage site is quite flexible to accept insertions of different length and with sequences from different possible origins. Different from recent cleavage site insertions, the origin of the insert here is not from the viral genome but from host 28S ribosomal RNA (rRNA) instead. This is a novelty for a natural acquisition as a similar insertion has so far only been observed in a laboratory strain before. Given the abundance of viral and host RNA in infected cells, the acquisition of a pathogenicity-enhancing extended cleavage site through a similar route by other low-pathogenic avian strains in future does not seem unlikely. Important for surveillance of these H7N3 strains, the structural sites known to enhance mammalian airborne transmission are dominated by the characteristic avian residues and the risk of human to human transmission should currently be low but should be monitored for future changes accordingly. This highly pathogenic H7N3 avian influenza strain acquired a novel extended cleavage site which likely originated from recombination with 28S rRNA from the avian host. Notably, this new virus can infect humans but currently lacks critical host receptor adaptations that would facilitate human to human transmission.
Newman, S. M.; Boynton, J. E.; Gillham, N. W.; Randolph-Anderson, B. L.; Johnson, A. M.; Harris, E. H.
1990-01-01
Transformation of chloroplast ribosomal RNA (rRNA) genes in Chlamydomonas has been achieved by the biolistic process using cloned chloroplast DNA fragments carrying mutations that confer antibiotic resistance. The sites of exchange employed during the integration of the donor DNA into the recipient genome have been localized using a combination of antibiotic resistance mutations in the 16S and 23S rRNA genes and restriction fragment length polymorphisms that flank these genes. Complete or nearly complete replacement of a region of the chloroplast genome in the recipient cell by the corresponding sequence from the donor plasmid was the most common integration event. Exchange events between the homologous donor and recipient sequences occurred preferentially near the vector:insert junctions. Insertion of the donor rRNA genes and flanking sequences into one inverted repeat of the recipient genome was followed by intramolecular copy correction so that both copies of the inverted repeat acquired identical sequences. Increased frequencies of rRNA gene transformants were achieved by reducing the copy number of the chloroplast genome in the recipient cells and by decreasing the heterology between donor and recipient DNA sequences flanking the selectable markers. In addition to producing bona fide chloroplast rRNA transformants, the biolistic process induced mutants resistant to low levels of streptomycin, typical of nuclear mutations in Chlamydomonas. PMID:1981764
Response Changes During Insertion of a Cochlear Implant Using Extracochlear Electrocochleography.
Giardina, Christopher K; Khan, Tatyana E; Pulver, Stephen H; Adunka, Oliver F; Buchman, Craig A; Brown, Kevin D; Pillsbury, Harold C; Fitzpatrick, Douglas C
2018-03-16
Electrocochleography is increasingly being utilized as an intraoperative monitor of cochlear function during cochlear implantation (CI). Intracochlear recordings from the advancing electrode can be obtained through the device by on-board capabilities. However, such recordings may not be ideal as a monitor because the recording electrode moves in relation to the neural and hair cell generators producing the responses. The purposes of this study were to compare two extracochlear recording locations in terms of signal strength and feasibility as intraoperative monitoring sites and to characterize changes in cochlear physiology during CI insertion. In 83 human subjects, responses to 90 dB nHL tone bursts were recorded both at the round window (RW) and then at an extracochlear position-either adjacent to the stapes or on the promontory just superior to the RW. Recording from the fixed, extracochlear position continued during insertion of the CI in 63 cases. Before CI insertion, responses to low-frequency tones at the RW were roughly 6 dB larger than when recording at either extracochlear site, but the two extracochlear sites did not differ from one another. During CI insertion, response losses from the promontory or adjacent to the stapes stayed within 5 dB in ≈61% (38/63) of cases, presumably indicating atraumatic insertions. Among responses which dropped more than 5 dB at any time during CI insertion, 12 subjects showed no response recovery, while in 13, the drop was followed by partial or complete response recovery by the end of CI insertion. In cases with recovery, the drop in response occurred relatively early (<15 mm insertion) compared to those where there was no recovery. Changes in response phase during the insertion occurred in some cases; these may indicate a change in the distributions of generators contributing to the response. Monitoring the electrocochleography during CI insertion from an extracochlear site reveals insertions that are potentially atraumatic show interaction with cochlear structures followed by response recovery or show interactions such that response losses persist to the end of recording.
Duellman, Tyler; Warren, Christopher; Yang, Jay
2014-01-01
Microribonucleic acids (miRNAs) work with exquisite specificity and are able to distinguish a target from a non-target based on a single nucleotide mismatch in the core nucleotide domain. We questioned whether miRNA regulation of gene expression could occur in a single nucleotide polymorphism (SNP)-specific manner, manifesting as a post-transcriptional control of expression of genetic polymorphisms. In our recent study of the functional consequences of matrix metalloproteinase (MMP)-9 SNPs, we discovered that expression of a coding exon SNP in the pro-domain of the protein resulted in a profound decrease in the secreted protein. This missense SNP results in the N38S amino acid change and a loss of an N-glycosylation site. A systematic study demonstrated that the loss of secreted protein was due not to the loss of an N-glycosylation site, but rather an SNP-specific targeting by miR-671-3p and miR-657. Bioinformatics analysis identified 41 SNP-specific miRNA targeting MMP-9 SNPs, mostly in the coding exon and an extension of the analysis to chromosome 20, where the MMP-9 gene is located, suggesting that SNP-specific miRNAs targeting the coding exon are prevalent. This selective post-transcriptional regulation of a target messenger RNA harboring genetic polymorphisms by miRNAs offers an SNP-dependent post-transcriptional regulatory mechanism, allowing for polymorphic-specific differential gene regulation. PMID:24627221
Robinson, James; Guethlein, Lisbeth A; Cereb, Nezih; Yang, Soo Young; Norman, Paul J; Marsh, Steven G E; Parham, Peter
2017-06-01
HLA class I glycoproteins contain the functional sites that bind peptide antigens and engage lymphocyte receptors. Recently, clinical application of sequence-based HLA typing has uncovered an unprecedented number of novel HLA class I alleles. Here we define the nature and extent of the variation in 3,489 HLA-A, 4,356 HLA-B and 3,111 HLA-C alleles. This analysis required development of suites of methods, having general applicability, for comparing and analyzing large numbers of homologous sequences. At least three amino-acid substitutions are present at every position in the polymorphic α1 and α2 domains of HLA-A, -B and -C. A minority of positions have an incidence >1% for the 'second' most frequent nucleotide, comprising 70 positions in HLA-A, 85 in HLA-B and 54 in HLA-C. The majority of these positions have three or four alternative nucleotides. These positions were subject to positive selection and correspond to binding sites for peptides and receptors. Most alleles of HLA class I (>80%) are very rare, often identified in one person or family, and they differ by point mutation from older, more common alleles. These alleles with single nucleotide polymorphisms reflect the germ-line mutation rate. Their frequency predicts the human population harbors 8-9 million HLA class I variants. The common alleles of human populations comprise 42 core alleles, which represent all selected polymorphism, and recombinants that have assorted this polymorphism.
Cereb, Nezih; Yang, Soo Young; Marsh, Steven G. E.; Parham, Peter
2017-01-01
HLA class I glycoproteins contain the functional sites that bind peptide antigens and engage lymphocyte receptors. Recently, clinical application of sequence-based HLA typing has uncovered an unprecedented number of novel HLA class I alleles. Here we define the nature and extent of the variation in 3,489 HLA-A, 4,356 HLA-B and 3,111 HLA-C alleles. This analysis required development of suites of methods, having general applicability, for comparing and analyzing large numbers of homologous sequences. At least three amino-acid substitutions are present at every position in the polymorphic α1 and α2 domains of HLA-A, -B and -C. A minority of positions have an incidence >1% for the ‘second’ most frequent nucleotide, comprising 70 positions in HLA-A, 85 in HLA-B and 54 in HLA-C. The majority of these positions have three or four alternative nucleotides. These positions were subject to positive selection and correspond to binding sites for peptides and receptors. Most alleles of HLA class I (>80%) are very rare, often identified in one person or family, and they differ by point mutation from older, more common alleles. These alleles with single nucleotide polymorphisms reflect the germ-line mutation rate. Their frequency predicts the human population harbors 8–9 million HLA class I variants. The common alleles of human populations comprise 42 core alleles, which represent all selected polymorphism, and recombinants that have assorted this polymorphism. PMID:28650991
Copy number determination of genetically-modified hematopoietic stem cells.
Schuesler, Todd; Reeves, Lilith; Kalle, Christof von; Grassman, Elke
2009-01-01
Human gene transfer with gammaretroviral, murine leukemia virus (MLV) based vectors has been shown to effectively insert and express transgene sequences at a level of therapeutic benefit. However, there are numerous reports of disruption of the normal cellular processes caused by the viral insertion, even of replication deficient gammaretroviral vectors. Current gammaretroviral and lentiviral vectors do not control the site of insertion into the genome, hence, the possibility of disruption of the target cell genome. Risk related to viral insertions is linked to the number of insertions of the transgene into the cellular DNA, as has been demonstrated for replication competent and replication deficient retroviruses in experiments. At high number of insertions per cell, cell transformation due to vector induced activation of proto-oncogenes is more likely to occur, in particular since more than one transforming event is needed for oncogenesis. Thus, determination of the vector copy number in bulk transduced populations, individual colony forming units, and tissue from the recipient of the transduced cells is an increasingly important safety assay and has become a standard, though not straightforward assay, since the inception of quantitative PCR.
Droplet-counting Microtitration System for Precise On-site Analysis.
Kawakubo, Susumu; Omori, Taichi; Suzuki, Yasutada; Ueta, Ikuo
2018-01-01
A new microtitration system based on the counting of titrant droplets has been developed for precise on-site analysis. The dropping rate was controlled by inserting a capillary tube as a flow resistance in a laboratory-made micropipette. The error of titration was 3% in a simulated titration with 20 droplets. The pre-addition of a titrant was proposed for precise titration within an error of 0.5%. The analytical performances were evaluated for chelate titration, redox titration and acid-base titration.
Comparing the landcapes of common retroviral insertion sites across tumor models
NASA Astrophysics Data System (ADS)
Weishaupt, Holger; Čančer, Matko; Engström, Cristopher; Silvestrov, Sergei; Swartling, Fredrik J.
2017-01-01
Retroviral tagging represents an important technique, which allows researchers to screen for candidate cancer genes. The technique is based on the integration of retroviral sequences into the genome of a host organism, which might then lead to the artificial inhibition or expression of proximal genetic elements. The identification of potential cancer genes in this framework involves the detection of genomic regions (common insertion sites; CIS) which contain a number of such viral integration sites that is greater than expected by chance. During the last two decades, a number of different methods have been discussed for the identification of such loci and the respective techniques have been applied to a variety of different retroviruses and/or tumor models. We have previously established a retrovirus driven brain tumor model and reported the CISs which were found based on a Monte Carlo statistics derived detection paradigm. In this study, we consider a recently proposed alternative graph theory based method for identifying CISs and compare the resulting CIS landscape in our brain tumor dataset to those obtained when using the Monte Carlo approach. Finally, we also employ the graph-based method to compare the CIS landscape in our brain tumor model with those of other published retroviral tumor models.
Assessment of the relationship between ACE I/D gene polymorphism and renal allograft survival.
Yang, Chun-Hua; Lu, Yi; Chen, Xue-Xia; Xian, Wen-Feng; Tu, Wei-Feng; Li, Hong-Yan
2015-12-01
The relationship between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism and renal allograft survival after renal transplantation from the published reports are still debatable. This study was performed to evaluate the relationship between the ACE I/D gene polymorphism and renal allograft survival after renal transplantation using meta-analysis. Eligible studies were identified from PubMed and Cochrane Library on 1 November 2014, and eligible studies were recruited and synthesized using a meta-analysis methodology. Twelve investigations were included in this meta-analysis for the assessment of the relationship between the ACE I/D gene polymorphism and renal allograft survival. In this meta-analysis, the ACE I/D gene polymorphism was not associated with renal allograft survival after renal transplantation for overall populations, Caucasians, Brazilians and Africans. Interestingly, the ACE D allele and DD genotype were associated with renal allograft survival after renal transplantation in the Asian population. ACE D allele and DD genotype were associated with renal allograft survival after renal transplantation in the Asian population. However, more studies should be performed to confirm this association. © The Author(s) 2015.
ACE insertion/deletion polymorphism and submaximal exercise hemodynamics in postmenopausal women.
Hagberg, James M; McCole, Steve D; Brown, Michael D; Ferrell, Robert E; Wilund, Kenneth R; Huberty, Andrea; Douglass, Larry W; Moore, Geoffrey E
2002-03-01
We sought to determine whether the angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) polymorphism is associated with submaximal exercise cardiovascular hemodynamics. Postmenopausal healthy women (20 sedentary, 20 physically active, 22 endurance athletes) had cardiac output (acetylene rebreathing) measured during 40, 60, and 80% VO(2 max) exercise. The interaction of ACE genotype and habitual physical activity (PA) level was significantly associated with submaximal exercise systolic blood pressure, with only sedentary women exhibiting differences among genotypes. No significant effects of ACE genotype or its interaction with PA levels was observed for submaximal exercise diastolic blood pressure. ACE genotype was significantly associated with submaximal exercise heart rate (HR) with ACE II having approximately 10 beats/min higher HR than ACE ID/DD genotype women. ACE genotype did not interact significantly with habitual PA level to associate with submaximal exercise HR. ACE genotype was not independently, but was interactively with habitual PA levels, associated with differences in submaximal exercise cardiac output and stroke volume. For cardiac output, ACE II genotype women athletes had ~25% greater cardiac output than ACE DD genotype women athletes, whereas for stroke volume genotype-dependent differences were observed in both the physically active and athletic women. ACE genotype was not significantly associated, either independently or interactively with habitual PA levels, with submaximal exercise total peripheral resistance or arteriovenous O(2) difference. Thus the common ACE locus polymorphic variation is associated with many submaximal exercise cardiovascular hemodynamic responses.
Direct versus indirect ACL femoral attachment fibres and their implications on ACL graft placement.
Moulton, Samuel G; Steineman, Brett D; Haut Donahue, Tammy L; Fontboté, Cristián A; Cram, Tyler R; LaPrade, Robert F
2017-01-01
To further elucidate the direct and indirect fibre insertion morphology within the human ACL femoral attachment using scanning electron microscopy and determine where in the footprint each fibre type predominates. The hypothesis was that direct fibre attachment would be found centrally in the insertion site, while indirect fibre attachment would be found posteriorly adjacent to the posterior articular cartilage. Ten cadaveric knees were dissected to preserve and isolate the entirety of the femoral insertion of the ACL. Specimens were then prepared and evaluated with scanning electron microscopy to determine insertional fibre morphology and location. The entirety of the fan-like projection of the ACL attachment site lay posterior to the lateral intercondylar ridge. In all specimens, a four-phase architecture, consistent with previous descriptions of direct fibres, was found in the centre of the femoral attachment site. The posterior margin of the ACL attachment attached directly adjacent to the posterior articular cartilage with some fibres coursing into it. The posterior portion of the ACL insertion had a two-phase insertion, consistent with previous descriptions of indirect fibres. The transition from the ligament fibres to bone had less interdigitations, and the interdigitations were significantly smaller (p < 0.001) compared to the transition in the direct fibre area. The interdigitations of the direct fibres were 387 ± 81 μm (range 282-515 μm) wide, while the interdigitations of indirect fibres measured 228 ± 75 μm (range 89-331 μm). The centre of the ACL femoral attachment consisted of a direct fibre structure, while the posterior portion had an indirect fibre structure. These results support previous animal studies reporting that the centre of the ACL femoral insertion was comprised of the strongest reported fibre type. Clinically, the femoral ACL reconstruction tunnel should be oriented to cover the entirety of the central direct ACL fibres and may need to be customized based on graft type and the fixation device used during surgery.
Blum, Kenneth; Werner, Tonia; Carnes, Stefanie; Carnes, Patrick; Bowirrat, Abdalla; Giordano, John; Marlene-Oscar-Berman; Gold, Mark
2014-01-01
The nucleus accumbens, a site within the ventral striatum, plays a prominent role in mediating the reinforcing effects of drugs of abuse, food, sex, and other addictions. Indeed, it is generally believed that this structure mandates motivated behaviors such as eating, drinking, and sexual activity, which are elicited by natural rewards and other strong incentive stimuli. This article focuses on sex addiction, but we hypothesize that there is a common underlying mechanism of action for the powerful effects that all addictions have on human motivation. That is, biological drives may have common molecular genetic antecedents, which if impaired, lead to aberrant behaviors. Based on abundant scientific support, we further hypothesize that dopaminergic genes, and possibly other candidate neurotransmitter-related gene polymorphisms, affect both hedonic and anhedonic behavioral outcomes. Genotyping studies already have linked gene polymorphic associations with alcohol and drug addictions and obesity, and we anticipate that future genotyping studies of sex addicts will provide evidence for polymorphic associations with specific clustering of sexual typologies based on clinical instrument assessments. We recommend that scientists and clinicians embark on research coupling the use of neuroimaging tools with dopaminergic agonistic agents to target specific gene polymorphisms systematically for normalizing hyper- or hypo-sexual behaviors. PMID:22641964
Distribution of the most common polymorphisms in TYMS gene in Slavic population of central Europe.
Pastorakova, A; Chandogova, D; Chandoga, J; Luha, J; Bohmer, D; Malova, J; Braxatorisova, T; Juhosova, M; Reznakova, S; Petrovic, R
2017-01-01
Thymidylate synthetase (TS) plays a critical role in the de novo synthesis of dTMP inside the cell. Therefore, TS is a suitable target for cytotoxic drugs such as fluoropyrimidines. Drug efficacy and toxicity depend on the intracellular level of TS, which is significantly influenced by the polymorphisms in the 5'UTR (TSER - rs45445694, TSER*3G>C - rs2853542) and 3'UTR (1494del TTAAAG - rs151264360) of TYMS gene. Polymorphic variants of TYMS gene affect TS activity via gene expression and transcript stability. Patients who undergo fluoropyrimidine therapy may benefit from genetic testing prior to the administration of chemotherapy. At the 5' terminus of TYMS, there is a polymorphic region represented by a variable number of 28bp long tandem repeats (2-9 tandems) with the G or C nucleotide variant (SNP G>C). The 3'end of TYMS gene may decrease the stability of mRNA in the case of 6 base deletion (1494del6, D). In our study, we have focused on testing of TYMS gene polymorphisms, determination of TYMS variant frequencies in Western Slavic population and comparison of Slovak population with other populations.We performed identification of 5'UTR (rs45445694 - TSER*2 or TSER*3; rs2853542 - TSER*3G>C; TSER*3+ins6) and 3'UTR (rs151264360/1494del6/D) polymorphic regions of TYMS gene among 96 volunteers by PCR-RFLP and fragment analysis. Slovak frequencies of selected polymorphisms were established as follows: the frequency of TSER*2, TSER*3, TSER*3G>C, 1494del6/D and I to be 41%, 59%, 34%, 37.5% and 62.5% respectively. The high resolution of the capillary electrophoresis technique allowed among TSER*3 group identification of a subgroup of four individuals with rare 6bp insertion in 3R allele, id est 2.1% TSER*3+ins6 allele frequency. In our study, we have revealed individuals with rare G>C substitution in the first 28bp tandem repeat of TSER*2 promoter enhancer region (rs183205964) as well, the overall frequency of this polymorphic allele in Slovak population was 2.1%. Our results proved that Slovak population is in Hardy-Weinberg equilibrium and proportion of TYMS polymorphisms is in accordance with other published data.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Xiangjie; Belser, Jessica A.; Tumpey, Terrence M., E-mail: tft9@cdc.gov
In 2012, an avian influenza A H7N3 (A/Mexico/InDRE7218/2012; Mx/7218) virus was responsible for two confirmed cases of human infection and led to the death or culling of more than 22 million chickens in Jalisco, Mexico. Interestingly, this virus acquired an 8-amino acid (aa)-insertion (..PENPK-DRKSRHRR-TR/GLF) near the hemagglutinin (HA) cleavage site by nonhomologous recombination with host rRNA. It remains unclear which specific residues at the cleavage site contribute to the virulence of H7N3 viruses in mammals. Using loss-of-function approaches, we generated a series of cleavage site mutant viruses by reverse genetics and characterized the viruses in vitro and in vivo. Wemore » found that the 8-aa insertion and the arginine at position P4 of the Mx/7218 HA cleavage site are essential for intracellular HA cleavage in 293T cells, but have no effect on the pH of membrane fusion. However, we identified a role for the histidine residue at P5 position in viral fusion pH. In mice, the 8-aa insertion is required for Mx/7218 virus virulence; however, the basic residues upstream of the P4 position are dispensable for virulence. Overall, our study provides the first line of evidence that the insertion in the Mx/7218 virus HA cleavage site confers its intracellular cleavability, and consequently contributes to enhanced virulence in mice. - Highlights: • An avian influenza H7N3 virus acquired a unique 8-amino acid (aa) insertion. • The role of specific basic residues in the HA insertion in viral pathogenesis was determined. • In mice, the 8-aa insertion is required for H7N3 virus virulence. • The R residue at position P4 is essential for HA intracellular cleavage and virus virulence.« less
Capparé, Paolo; Vinci, Raffaele; Di Stefano, Danilo Alessio; Traini, Tonino; Pantaleo, Giuseppe; Gherlone, Enrico Felice; Gastaldi, Giorgio
2015-10-01
Quantitative intraoperative evaluation of bone quality at implant placement site and postinsertion implant primary stability assessment are two key parameters to perform implant-supported rehabilitation properly. A novel micromotor has been recently introduced allowing to measure bone density at implant placement site and to record implant insertion-related parameters, such as the instantaneous, average and peak insertion torque values, and the insertion torque/depth integral. The aim of this study was to investigate in vivo if any correlation existed between initial bone-to-implant contact (BIC) and bone density and integral values recorded with the instrument. Twenty-five patients seeking for implant-supported rehabilitation of edentulous areas were consecutively treated. Before implant placement, bone density at the insertion site was measured. For each patient, an undersized 3.3 × 8-mm implant was placed, recording the insertion torque/depth integral values. After 15 minutes, the undersized implant was retrieved with a 0.5 mm-thick layer of bone surrounding it. Standard implants were consequently placed. Retrieved implants were analyzed for initial BIC quantification after fixation, dehydration, acrylic resin embedment, sections cutting and grinding, and toluidine-blue and acid fuchsine staining. Correlation between initial BIC values, bone density at the insertion site, and the torque/depth integral values was investigated by linear regression analysis. A significant linear correlation was found to exist between initial BIC and (a) bone density at the insertion site (R = 0.96, explained variance R(2) = 0.92) and (b) torque/depth integral at placement (R = 0.81, explained variance R(2) = 0.66). The system provided quantitative, reliable data correlating significantly with immediate postinsertion initial BIC, and could therefore represent a valuable tool both for clinical research and for the oral implantologist in his/her daily clinical practice. © 2015 Wiley Periodicals, Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, Young-Min; Kim, Chan-Young; Yang, Doo-Hyun
Purpose. To evaluate the feasibility and effectiveness of feeding tube insertion and enteral feeding for the treatment of postoperative gastrointestinal anastomotic obstruction and leakage. Materials and Methods. From June 1999 to June 2002, thirty-four cases of postoperative gastrointestinal anastomotic obstruction and leakage after surgery for gastric carcinoma were treated by insertion of a feeding tube under fluoroscopic guidance. Twenty-one patients were male and 13 were female. The patients' ages ranged from 39 to 74 years (mean age: 61 years). All the patients experienced vomiting, and 15 patients had anastomotic site or duodenal stump leakage. We evaluated the feasibility of feedingmore » tube insertion for enteral feeding to improve the obstruction and facilitate leakage site closure, and the patients' nutritional benefit was also evaluated by checking the serum albumin level between pre- and post-enteral feeding via the feeding tube.Results. Thirty-two patients (94%) were successfully managed by feeding tube insertion, but the remaining two were not managed, and this was due to severe angulations at the anastomotic site. The procedure times for feeding tube insertion ranged from 15 to 60 minutes (mean time: 45 minutes). Twenty-eight patients experienced symptomatic relief of gastrointestinal obstruction, and they were able to resume a normal regular diet after feeding tube removal. Three patients underwent stent insertion due to recurrent symptoms, and one patient underwent jejunostomy feeding due to the presence of a persistent leakage site. Eleven patients achieved leakage site closure after enteral feeding via a feeding tube. The serum albumin level was significant, increased from pre-enteral feeding (2.65 {+-} 0.37 g/dL) to the post-enteral feeding (3.64 {+-} 0.58 g/dL) via the feeding tube (p < 0.001). The duration of follow-up ranged from one to 53 months (mean: 23 months). Conclusion. The insertion of a feeding tube for enteral feeding under fluoroscopic guidance is safe, and it provides effective relief from gastrointestinal anastomotic site obstruction and leakage after gastric surgery. Moreover, our findings indicate that feeding tube insertion for enteral feeding may be used as the primary procedure to treat postoperative anastomotic obstruction and leakage.« less
Venken, Koen J. T.; Schulze, Karen L.; Haelterman, Nele A.; Pan, Hongling; He, Yuchun; Evans-Holm, Martha; Carlson, Joseph W.; Levis, Robert W.; Spradling, Allan C.; Hoskins, Roger A.; Bellen, Hugo J.
2011-01-01
We demonstrate the versatility of a collection of insertions of the transposon Minos mediated integration cassette (MiMIC), in Drosophila melanogaster. MiMIC contains a gene-trap cassette and the yellow+ marker flanked by two inverted bacteriophage ΦC31 attP sites. MiMIC integrates almost at random in the genome to create sites for DNA manipulation. The attP sites allow the replacement of the intervening sequence of the transposon with any other sequence through recombinase mediated cassette exchange (RMCE). We can revert insertions that function as gene traps and cause mutant phenotypes to wild type by RMCE and modify insertions to control GAL4 or QF overexpression systems or perform lineage analysis using the Flp system. Insertions within coding introns can be exchanged with protein-tag cassettes to create fusion proteins to follow protein expression and perform biochemical experiments. The applications of MiMIC vastly extend the Drosophila melanogaster toolkit. PMID:21985007
The polymorphisms of LCR, E6, and E7 of HPV-58 isolates in Yunnan, Southwest China.
Xi, Juemin; Chen, Junying; Xu, Miaoling; Yang, Hongying; Wen, Songjiao; Pan, Yue; Wang, Xiaodan; Ye, Chao; Qiu, Lijuan; Sun, Qiangming
2018-04-25
Variations in HPV LCR/E6/E7 have been shown to be associated with the viral persistence and cervical cancer development. So far, there are few reports about the polymorphisms of the HPV-58 LCR/E6/E7 sequences in Southwest China. This study aims to characterize the gene polymorphisms of the HPV-58 LCR/E6/E7 sequences in women of Southwest China, and assess the effects of variations on the immune recognition of viral E6 and E7 antigens. Twelve LCR/E6/E7 of the HPV-58 isolates were amplified and sequenced. A neighbor-joining phylogenetic tree was constructed by MEGA 7.0, followed by the secondary structure prediction of the related proteins using PSIPRED v3.3. The selection pressure acting on the HPV-58 E6 and E7 coding regions was estimated by Bayes empirical Bayes analysis of PAML 4.8. Meanwhile, the MHC class-I and II binding peptides were predicted by the ProPred-I server and ProPred server. The transcription factor binding sites in the HPV-58 LCR were analyzed using the JASPAR database. Twenty nine SNPs (20 in the LCR, 3 in the E6, 6 in the E7) were identified at 27 nucleotide sites across the HPV-58 LCR/E6/E7. From the most variable to the least variable, the nucleotide variations were LCR > E7 > E6. The combinations of all the SNPs resulted in 11 unique sequences, which were clustered into the A lineage (7 belong to A1, 2 belong to A2, and 2 belong to A3). An insertion (TGTCAGTTTCCT) was found between the nucleotide sites 7280 and 7281 in 2 variants, and a deletion (TTTAT) was found between 7429 and 7433 in 1 variant. The most common non-synonymous substitution V77A in the E7 was observed in the sequences encoding the α-helix. 63G in the E7 was determined to be the only one positively selected site in the HPV-58 E6/E7 sequences. Six non-synonymous amino acid substitutions (including S71F and K93 N in the E6, and T20I, G41R, G63S/D, and V77A in the E7) were affecting multiple putative epitopes for both CD4 + and CD8 + T-cells. In the LCR, C7265G and C7266T were the most variable sites and were the potential binding sites for the transcription factor SOX10. These results provide an insight into the intrinsic geographical relatedness and biological differences of the HPV-58 variants, and contribute to further research on the HPV-58 epidemiology, carcinogenesis, and therapeutic vaccine development.
2011-01-01
Background Major Histocompatibility Complex (MHC) genes are central to vertebrate immune response and are believed to be under balancing selection by pathogens. This hypothesis has been supported by observations of extremely high polymorphism, elevated nonsynonymous to synonymous base pair substitution rates and trans-species polymorphisms at these loci. In equids, the organization and variability of this gene family has been described, however the full extent of diversity and selection is unknown. As selection is not expected to act uniformly on a functional gene, maximum likelihood codon-based models of selection that allow heterogeneity in selection across codon positions can be valuable for examining MHC gene evolution and the molecular basis for species adaptations. Results We investigated the evolution of two class II MHC genes of the Equine Lymphocyte Antigen (ELA), DRA and DQA, in the genus Equus with the addition of novel alleles identified in plains zebra (E. quagga, formerly E. burchelli). We found that both genes exhibited a high degree of polymorphism and inter-specific sharing of allele lineages. To our knowledge, DRA allelic diversity was discovered to be higher than has ever been observed in vertebrates. Evidence was also found to support a duplication of the DQA locus. Selection analyses, evaluated in terms of relative rates of nonsynonymous to synonymous mutations (dN/dS) averaged over the gene region, indicated that the majority of codon sites were conserved and under purifying selection (dN
Azimzadeh, Pedram; Romani, Sara; Mohebbi, Seyed Reza; Mahmoudi, Touraj; Vahedi, Mohsen; Fatemi, Seyed Reza; Zali, Narges; Zali, Mohammad Reza
2012-10-01
MicroRNAs (miRNAs) are agents of post-transcriptional gene expression, and they can affect many functions of an individual cell or tissue from extracellular matrix production to inflammatory processes and tumor development. We aimed to determine the possible role of miRNA-binding site polymorphisms located in five cancer-related genes: IL-16, CDKN2A (p16), RAF1, PTGER4, and ITGB4 in colorectal cancer (CRC) risk modification in an Iranian population. This study was performed on 643 individuals (249 CRC cases and 394 healthy controls). We selected five cancer-related genes (IL-16, CDKN2A (p16), RAF1, PTGER4, and ITGB4) and investigated the genotypes of the 3' untranslated region miRNA-binding site polymorphisms in these genes in our study population. The restriction fragment length polymorphism results were confirmed by a direct sequencing method. We found a statistically significant difference between the rs1131445 polymorphism of the IL-16 gene and CRC. The frequencies of the genotypes TT, CT, and CC in controls were 51%, 40.4%, and 8.6%, respectively, and in cases were 41.4%, 44.1%, and 14.5%, respectively, which shows a significant association between the CC genotype of the rs1131445 polymorphism and CRC (P = 0.004). The frequency of the C allele in the CRC group was higher than in the controls, and the C allele of the rs1131445 polymorphism was found to be in association with CRC (P = 0.009). These associations remained significant after Bonferroni's correction for multiple testing. We found that the AA genotype of the rs743554 polymorphism in the ITGB4 gene and the T allele of the rs1051208 polymorphism of the RAF1 gene were associated with the risk of CRC in females; however, after Bonferroni's correction we found that they were non-significant. Finally, we can conclude that a significant relationship exists between the miRNA-binding site polymorphism of the IL-16 gene and CRC risk in the Iranian population. Copyright © 2012 Elsevier Inc. All rights reserved.
Beare, Paul A.; Samuel, James E.; Howe, Dale; Virtaneva, Kimmo; Porcella, Stephen F.; Heinzen, Robert A.
2006-01-01
Coxiella burnetii, a gram-negative obligate intracellular bacterium, causes human Q fever and is considered a potential agent of bioterrorism. Distinct genomic groups of C. burnetii are revealed by restriction fragment-length polymorphisms (RFLP). Here we comprehensively define the genetic diversity of C. burnetii by hybridizing the genomes of 20 RFLP-grouped and four ungrouped isolates from disparate sources to a high-density custom Affymetrix GeneChip containing all open reading frames (ORFs) of the Nine Mile phase I (NMI) reference isolate. We confirmed the relatedness of RFLP-grouped isolates and showed that two ungrouped isolates represent distinct genomic groups. Isolates contained up to 20 genomic polymorphisms consisting of 1 to 18 ORFs each. These were mostly complete ORF deletions, although partial deletions, point mutations, and insertions were also identified. A total of 139 chromosomal and plasmid ORFs were polymorphic among all C. burnetii isolates, representing ca. 7% of the NMI coding capacity. Approximately 67% of all deleted ORFs were hypothetical, while 9% were annotated in NMI as nonfunctional (e.g., frameshifted). The remaining deleted ORFs were associated with diverse cellular functions. The only deletions associated with isogenic NMI variants of attenuated virulence were previously described large deletions containing genes involved in lipopolysaccharide (LPS) biosynthesis, suggesting that these polymorphisms alone are responsible for the lower virulence of these variants. Interestingly, a variant of the Australia QD isolate producing truncated LPS had no detectable deletions, indicating LPS truncation can occur via small genetic changes. Our results provide new insight into the genetic diversity and virulence potential of Coxiella species. PMID:16547017
Advances in cancer epidemiology in Japan.
Tanaka, Hideo
2014-02-15
Epidemiologists in Japan have been performing calculations to estimate nationwide cancer incidence rates as well as 5-year survival rates using population-based cancer registry data. There have been remarkable changes in cancer incidence and/or mortality in cancers of the lung, liver and stomach, which were thought to be attributed to the changing impact of exposure to cigarette smoking, chronic hepatitis C virus infection and Helicobacter pylori infection, respectively. In systematic reviews providing evidence in risk/protective factors for cancer sites using case-control and cohort studies of the Japanese population, there were associations between cancer sites (esophagus, stomach, colo-rectum, liver, pancreas, lung and breast) and various lifestyle factors. In the past 10 years, a hospital-based case-control study at Aichi Cancer Center provided valuable evidence of gene-environment interaction on the development of cancer [i.e., the effects of aldehyde dehydrogenase-2 (ALDH2) polymorphism and heavy alcohol drinking on esophageal cancer, ALDH2 polymorphism and smoking on lung cancer, methylenetetrahydrofolate reductase polymorphism and heavy alcohol drinking on pancreatic cancer]. The database with stored DNA was also used and identified seven loci containing significant but low-penetrance polymorphisms associated with the development of breast cancer. These findings together with established risk factors are likely to be useful to predict personalized breast cancer risk in East Asian women. In 2005, the Japan Multi-Institution Collaborative Cohort (J-MICC) study was launched to elucidate gene-environment interactions as well as to confirm preclinical diagnostic biomarkers of cancer. J-MICC, which has recruited 92,000 healthy individuals by the end of 2012, will follow the individuals until 2025. © 2013 UICC.
Fukushima, Yaeko
2017-04-01
The goal of the study was to survey ankle joint disorder in male senior high school and college student basketball players based on the results of an ultrasonographic medical check-up of the ankle joint. The subjects were 17 senior high school student and 19 college student basketball players. Ultrasonography, evaluation of ATFL injury, and examination of the talocrural joint region were performed. The subjects were grouped based on the presence or absence of old ATFL injury, and subjects with ATFL injury were classified by the injured region: fibular insertion site, parenchyma, and talar insertion site. The talocrural joint region was evaluated based on the areas of the lateral margin, central region, and medial margin, and sites with an irregular bone contour and osteophyte were counted individually. The questionnaire asked about the patients' history of ankle injuries. A questionnaire survey revealed that 70-79% of all subjects had experienced a sprain at least once and 21-29% had frequently sprained the left or right foot 10 or more times in the past. On ultrasonography, there was no significant difference in ligament injury or injured site between the senior high school and college students, but the number of osteochondral findings in the talocrural joint region was significantly higher in the college students. In addition, the number of injured sites significantly increased in those with 10 or more years of playing experience. These results suggest that disorder of the talocrural joint region progresses with an increase in years of experience in student basketball players who do not take specific preventive measures against this injury.
Guo, Yuxin; Shen, Chunmei; Meng, Haotian; Dong, Qian; Kong, Tingting; Yang, Chunhua; Wang, Hongdan; Jin, Rui; Zhu, Bofeng
2016-12-01
In recent years, Insertion/Deletion (InDel) polymorphisms have become a hot area of forensic research. In this study, 30 InDel loci were selected to investigate the genetic polymorphisms of Tibetan groups, which are from Tibet Autonomous Region and Qinghai province of China, and explore the genetic relationships between Tibetan groups and other groups. Allele frequencies of the 30 InDel loci ranged from 0.1219 (HLD111) to 0.5609 (HLD57) in the Tibet Tibetan group and 0.1639 (HLD118) to 0.5655 (HLD124) in the Qinghai Tibetan group. The combined power of discrimination, matching probability, and power of exclusion were 0.999999999986, 0.999999988, and 0.9913 in the Tibet Tibetan group, respectively, and 0.99999999999204, 0.9999999796, and 0.9862 in the Qinghai Tibetan group. The results of principal component analysis, phylogenetic tree, and population structure demonstrated that the four Tibetan groups (Tibetan1, Tibetan2, Tibet, and Qinghai Tibetan groups) clustered together and had relatively close genetic relationships with nine Asian groups and then European and Amerindian groups.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Yiman; Pelliccione, Christopher J.; Brady, Alexander B.
Here, we report an extensive study on fundamental properties that determine the functional electrochemistry of ZnFe 2O 4 spinel (theoretical capacity of 1000 mAh/g). For the first time, the reduction mechanism is followed through a combination of in situ X-ray diffraction data, synchrotron based powder diffraction, and ex-situ extended X-ray absorption fine structure allowing complete visualization of reduction products irrespective of their crystallinity. The first 0.5 electron equivalents (ee) do not significantly change the starting crystal structure. Subsequent lithiation results in migration of Zn 2+ ions from 8a tetrahedral sites into vacant 16c sites. Density functional theory shows that Limore » + ions insert into 16c site initially and then 8a site with further lithiation. Fe metal is formed over the next eight ee of reduction with no evidence of concurrent Zn 2+ reduction to Zn metal. Despite the expected formation of LiZn alloy from the electron count, we find no evidence for this phase under the tested conditions. Additionally, upon oxidation to 3 V, we observe an FeO phase with no evidence of Fe 2O 3. Electrochemistry data show higher electron equivalent transfer than can be accounted for solely based on ZnFe 2O 4 reduction indicating excess capacity ascribed to carbon reduction or surface electrolyte interphase formation.« less
Zhang, Yiman; Pelliccione, Christopher J.; Brady, Alexander B.; ...
2017-04-24
Here, we report an extensive study on fundamental properties that determine the functional electrochemistry of ZnFe 2O 4 spinel (theoretical capacity of 1000 mAh/g). For the first time, the reduction mechanism is followed through a combination of in situ X-ray diffraction data, synchrotron based powder diffraction, and ex-situ extended X-ray absorption fine structure allowing complete visualization of reduction products irrespective of their crystallinity. The first 0.5 electron equivalents (ee) do not significantly change the starting crystal structure. Subsequent lithiation results in migration of Zn 2+ ions from 8a tetrahedral sites into vacant 16c sites. Density functional theory shows that Limore » + ions insert into 16c site initially and then 8a site with further lithiation. Fe metal is formed over the next eight ee of reduction with no evidence of concurrent Zn 2+ reduction to Zn metal. Despite the expected formation of LiZn alloy from the electron count, we find no evidence for this phase under the tested conditions. Additionally, upon oxidation to 3 V, we observe an FeO phase with no evidence of Fe 2O 3. Electrochemistry data show higher electron equivalent transfer than can be accounted for solely based on ZnFe 2O 4 reduction indicating excess capacity ascribed to carbon reduction or surface electrolyte interphase formation.« less
Prospective comparison of two management strategies of central venous catheters in burn patients.
Kealey, G P; Chang, P; Heinle, J; Rosenquist, M D; Lewis, R W
1995-03-01
Central venous catheters (CVCs) are associated with sepsis in burn patients. This study was undertaken to compare two strategies of CVC management in patients with major burn injuries. Forty-two burn patients with major burn injuries were randomly assigned to undergo site change every 48 hours of the CVC or to undergo wire guide exchange of the CVC every 48 hours at the same site. Catheter insertion site, distance from the burn wound, cultures of catheter tips, and blood cultures were obtained from all patients in a prospective manner. There was no difference in the incidence of CVC sepsis between the two groups studied. CVCs inserted less than 5 cm from the burn wound developed bacterial contamination at an earlier time than CVCs inserted more than 5 cm from the burn wound. There was no advantage to changing the CVC insertion site every 48 hours. Changing the CVC using the wire guide technique did not prevent, nor predict, CVC bacterial contamination.
Editor’s note: This article was originally published on the Center for Cancer Research website. When the Human Immunodeficiency Virus (HIV) infects a cell, the virus inserts a copy of its genetic material into the host cell’s DNA. The inserted genetic material, which is also called a provirus, is used to produce new viruses. Because the viral DNA can be inserted at many sites
Mitochondrial DNA transfer to the nucleus generates extensive insertion site variation in maize.
Lough, Ashley N; Roark, Leah M; Kato, Akio; Ream, Thomas S; Lamb, Jonathan C; Birchler, James A; Newton, Kathleen J
2008-01-01
Mitochondrial DNA (mtDNA) insertions into nuclear chromosomes have been documented in a number of eukaryotes. We used fluorescence in situ hybridization (FISH) to examine the variation of mtDNA insertions in maize. Twenty overlapping cosmids, representing the 570-kb maize mitochondrial genome, were individually labeled and hybridized to root tip metaphase chromosomes from the B73 inbred line. A minimum of 15 mtDNA insertion sites on nine chromosomes were detectable using this method. One site near the centromere on chromosome arm 9L was identified by a majority of the cosmids. To examine variation in nuclear mitochondrial DNA sequences (NUMTs), a mixture of labeled cosmids was applied to chromosome spreads of ten diverse inbred lines: A188, A632, B37, B73, BMS, KYS, Mo17, Oh43, W22, and W23. The number of detectable NUMTs varied dramatically among the lines. None of the tested inbred lines other than B73 showed the strong hybridization signal on 9L, suggesting that there is a recent mtDNA insertion at this site in B73. Different sources of B73 and W23 were examined for NUMT variation within inbred lines. Differences were detectable, suggesting either that mtDNA is being incorporated or lost from the maize nuclear genome continuously. The results indicate that mtDNA insertions represent a major source of nuclear chromosomal variation.
Knobloch, Johannes K.-M.; Nedelmann, Max; Kiel, Kathrin; Bartscht, Katrin; Horstkotte, Matthias A.; Dobinsky, Sabine; Rohde, Holger; Mack, Dietrich
2003-01-01
Transposon mutagenesis with the Enterococcus faecalis transposon Tn917 is a genetic approach frequently used to identify genes related with specific phenotypes in gram-positive bacteria. We established an arbitrary PCR for the rapid and easy identification of Tn917 insertion sites in Staphylococcus epidermidis with six independent, well-characterized biofilm-negative Tn917 transposon mutants, which were clustered in the icaADBC gene locus or harbor Tn917 in the regulatory gene rsbU. For all six of these mutants, short chromosomal DNA fragments flanking both transposon ends could be amplified. All fragments were sufficient to correctly identify the Tn917 insertion sites in the published S. epidermidis genomes. By using this technique, the Tn917 insertion sites of three not-yet-characterized biofilm-negative or nonmucoid mutants were identified. In the biofilm-negative and nonmucoid mutant M12, Tn917 is inserted into a gene homologous to the regulatory gene purR of Bacillus subtilis and Staphylococcus aureus. The Tn917 insertions of the nonmucoid but biofilm-positive mutants M16 and M20 are located in genes homologous to components of the phosphoenolpyruvate-sugar phosphotransferase system (PTS) of B. subtilis, S. aureus, and Staphylococcus carnosus, indicating an influence of the PTS on the mucoid phenotype in S. epidermidis. PMID:14532029
A study of three polymorphic sites of ADA gene in colon cancer.
Spina, C; Saccucci, P; Cozzoli, E; Bottini, E; Gloria-Bottini, F
2010-12-01
Adenosine inhibits the immune response in tumors. Adenosine deaminase (ADA) controls adenosine level and as ecto-enzyme acts as costimulatory molecule of adenosine receptors and/or CD26. We examined ADA₁, ADA₂, ADA₆ polymorphic sites of ADA gene in 109 subjects with colon cancer from Rome's population and in 246 blood donors as controls from the same population. In colon cancer ADA₁*2/ADA₂*1 haplotype is more represented, while ADA₁*2/ADA₂*2 is less represented than in controls. ADA₂*2/ADA₆*2 is less represented in patients than in controls. Polymorphic sites of ADA might influence cell-mediated anti-tumor immune responses controlling adenosine level and extraenzymatic protein functions.
Park, Doori; Park, Su-Hyun; Ban, Yong Wook; Kim, Youn Shic; Park, Kyoung-Cheul; Kim, Nam-Soo; Kim, Ju-Kon; Choi, Ik-Young
2017-08-15
Genetically modified crops (GM crops) have been developed to improve the agricultural traits of modern crop cultivars. Safety assessments of GM crops are of paramount importance in research at developmental stages and before releasing transgenic plants into the marketplace. Sequencing technology is developing rapidly, with higher output and labor efficiencies, and will eventually replace existing methods for the molecular characterization of genetically modified organisms. To detect the transgenic insertion locations in the three GM rice gnomes, Illumina sequencing reads are mapped and classified to the rice genome and plasmid sequence. The both mapped reads are classified to characterize the junction site between plant and transgene sequence by sequence alignment. Herein, we present a next generation sequencing (NGS)-based molecular characterization method, using transgenic rice plants SNU-Bt9-5, SNU-Bt9-30, and SNU-Bt9-109. Specifically, using bioinformatics tools, we detected the precise insertion locations and copy numbers of transfer DNA, genetic rearrangements, and the absence of backbone sequences, which were equivalent to results obtained from Southern blot analyses. NGS methods have been suggested as an effective means of characterizing and detecting transgenic insertion locations in genomes. Our results demonstrate the use of a combination of NGS technology and bioinformatics approaches that offers cost- and time-effective methods for assessing the safety of transgenic plants.
Nam, Inho; Park, Jongseok; Park, Soomin; Bae, Seongjun; Yoo, Young Geun; Han, Jeong Woo; Yi, Jongheop
2017-05-24
Real-time analysis of changes in the atomic environment of materials is a cutting edge technology that is being used to explain reaction dynamics in many fields of science. Previously, this kind of analysis was only possible using heavy nucleonic equipment such as XANES and EXAFS, or Raman spectroscopy on a moderate scale. Here, a new methodology is described that can be used to track changes in crystalline developments during complex Li insertion reactions via the observation of structural color. To be specific, the changes in atomic crystalline and nanostructure are shown during Li insertion in a complex TiO 2 polymorph. Structural color corresponds to the refractive indices of materials originating from their atomic bonding nature and precise wave interferences in accordance with their nanostructure. Therefore, this new analysis simultaneously reveals changes in the nanostructure as well as changes in the atomic bonding nature of materials.
Mining of haplotype-based expressed sequence tag single nucleotide polymorphisms in citrus
2013-01-01
Background Single nucleotide polymorphisms (SNPs), the most abundant variations in a genome, have been widely used in various studies. Detection and characterization of citrus haplotype-based expressed sequence tag (EST) SNPs will greatly facilitate further utilization of these gene-based resources. Results In this paper, haplotype-based SNPs were mined out of publicly available citrus expressed sequence tags (ESTs) from different citrus cultivars (genotypes) individually and collectively for comparison. There were a total of 567,297 ESTs belonging to 27 cultivars in varying numbers and consequentially yielding different numbers of haplotype-based quality SNPs. Sweet orange (SO) had the most (213,830) ESTs, generating 11,182 quality SNPs in 3,327 out of 4,228 usable contigs. Summed from all the individually mining results, a total of 25,417 quality SNPs were discovered – 15,010 (59.1%) were transitions (AG and CT), 9,114 (35.9%) were transversions (AC, GT, CG, and AT), and 1,293 (5.0%) were insertion/deletions (indels). A vast majority of SNP-containing contigs consisted of only 2 haplotypes, as expected, but the percentages of 2 haplotype contigs varied widely in these citrus cultivars. BLAST of the 25,417 25-mer SNP oligos to the Clementine reference genome scaffolds revealed 2,947 SNPs had “no hits found”, 19,943 had 1 unique hit / alignment, 1,571 had one hit and 2+ alignments per hit, and 956 had 2+ hits and 1+ alignment per hit. Of the total 24,293 scaffold hits, 23,955 (98.6%) were on the main scaffolds 1 to 9, and only 338 were on 87 minor scaffolds. Most alignments had 100% (25/25) or 96% (24/25) nucleotide identities, accounting for 93% of all the alignments. Considering almost all the nucleotide discrepancies in the 24/25 alignments were at the SNP sites, it served well as in silico validation of these SNPs, in addition to and consistent with the rate (81%) validated by sequencing and SNaPshot assay. Conclusions High-quality EST-SNPs from different citrus genotypes were detected, and compared to estimate the heterozygosity of each genome. All the SNP oligo sequences were aligned with the Clementine citrus genome to determine their distribution and uniqueness and for in silico validation, in addition to SNaPshot and sequencing validation of selected SNPs. PMID:24175923
Tietz, Andreas; Frei, Reno; Dangel, Marc; Bolliger, Dora; Passweg, Jakob R; Gratwohl, Alois; Widmer, Andreas E
2005-08-01
To determine the efficacy and tolerability of octenidine hydrochloride, a non-alcoholic skin antiseptic, for the care of central venous catheter (CVC) insertion sites. Prospective, observational study. Bone marrow transplantation unit of a university hospital. All consecutive patients with a nontunneled CVC were enrolled prospectively after informed consent. Octenidine hydrochloride (0.1%) was applied for disinfection at the CVC insertion site during dressing changes. The following cultures were performed weekly as well as at the occurrence of any systemic inflammatory response syndrome criteria: cultures of the skin surrounding the CVC entry site, cultures of the three-way hub connected to the CVC, blood cultures, and cultures of the CVC tip on removal. Enhanced microbiological methods (skin swabs of a 24-cm2 standardized area, roll plate, and sonication of catheter tips) were applied. One hundred thirty-five CVCs were inserted in 62 patients during the study period and remained for a mean period of 19.1 days, corresponding to 2,462 catheter-days. Bacterial density at the insertion site declined substantially over time, and most cultures became negative 2 weeks after insertion. Only 6 patients had a documented catheter-related bloodstream infection. The incidence density was 2.39 catheter infections per 1,000 catheter-days. No side effects were noted with application of the antiseptic. Disinfection with a skin antiseptic that contains octenidine hydrochloride is highly active and well tolerated. It leads to a decrease in skin colonization over time and may be a new option for CVC care.
The application of the high throughput sequencing technology in the transposable elements.
Liu, Zhen; Xu, Jian-hong
2015-09-01
High throughput sequencing technology has dramatically improved the efficiency of DNA sequencing, and decreased the costs to a great extent. Meanwhile, this technology usually has advantages of better specificity, higher sensitivity and accuracy. Therefore, it has been applied to the research on genetic variations, transcriptomics and epigenomics. Recently, this technology has been widely employed in the studies of transposable elements and has achieved fruitful results. In this review, we summarize the application of high throughput sequencing technology in the fields of transposable elements, including the estimation of transposon content, preference of target sites and distribution, insertion polymorphism and population frequency, identification of rare copies, transposon horizontal transfers as well as transposon tagging. We also briefly introduce the major common sequencing strategies and algorithms, their advantages and disadvantages, and the corresponding solutions. Finally, we envision the developing trends of high throughput sequencing technology, especially the third generation sequencing technology, and its application in transposon studies in the future, hopefully providing a comprehensive understanding and reference for related scientific researchers.
Marçano, Ana Carolina Braga; Burke, Beverley; Gungadoo, Johannie; Wallace, Chris; Kaisaki, Pamela J; Woon, Peng Y; Farrall, Martin; Clayton, David; Brown, Morris; Dominiczak, Anna; Connell, John M; Webster, John; Lathrop, Mark; Caulfield, Mark; Samani, Nilesh; Gauguier, Dominique; Munroe, Patricia B
2007-01-01
Background Inositol polyphosphate phosphatase‐like 1 (INPPL1, SHIP2) is a negative regulator of insulin signalling and has previously been found to be associated with hypertension, obesity and type 2 diabetes in a cohort of families with diabetes in the UK presenting features of metabolic syndrome. In particular, a haplotype of three genetic polymorphisms (rs2276047, rs9886 and an insertion/deletion polymorphism in intron 1) was found to be strongly associated with increased susceptibility to hypertension. Objective and methods To assess if INPPL1 variants play a direct role in the development of essential hypertension, we genotyped the three previously associated INPPL1 polymorphisms in a cohort of 712 families with severe hypertension from the BRIGHT study transmission disequilibrium test cohort. Results We found no evidence of significant association between hypertension and any of the three INPPL1 polymorphisms or haplotypes (p>0.1). Conclusion These results suggest that INPPL1 variants may be involved in mechanisms causing hypertension in metabolic syndrome patients specifically. PMID:17557929
Ribosomal Binding Site Switching: An Effective Strategy for High-Throughput Cloning Constructions
Li, Yunlong; Zhang, Yong; Lu, Pei; Rayner, Simon; Chen, Shiyun
2012-01-01
Direct cloning of PCR fragments by TA cloning or blunt end ligation are two simple methods which would greatly benefit high-throughput (HTP) cloning constructions if the efficiency can be improved. In this study, we have developed a ribosomal binding site (RBS) switching strategy for direct cloning of PCR fragments. RBS is an A/G rich region upstream of the translational start codon and is essential for gene expression. Change from A/G to T/C in the RBS blocks its activity and thereby abolishes gene expression. Based on this property, we introduced an inactive RBS upstream of a selectable marker gene, and designed a fragment insertion site within this inactive RBS. Forward and reverse insertions of specifically tailed fragments will respectively form an active and inactive RBS, thus all background from vector self-ligation and fragment reverse insertions will be eliminated due to the non-expression of the marker gene. The effectiveness of our strategy for TA cloning and blunt end ligation are confirmed. Application of this strategy to gene over-expression, a bacterial two-hybrid system, a bacterial one-hybrid system, and promoter bank construction are also verified. The advantages of this simple procedure, together with its low cost and high efficiency, makes our strategy extremely useful in HTP cloning constructions. PMID:23185557
Ibeagha-Awemu, Eveline M.; Kgwatalala, Patrick; Ibeagha, Aloysius E.
2008-01-01
Genetic variations through their effects on gene expression and protein function underlie disease susceptibility in farm animal species. The variations are in the form of single nucleotide polymorphisms, deletions/insertions of nucleotides or whole genes, gene or whole chromosomal rearrangements, gene duplications, and copy number polymorphisms or variants. They exert varying degrees of effects on gene action, such as substitution of an amino acid for another, shift in reading frame and premature termination of translation, and complete deletion of entire exon(s) or gene(s) in diseased individuals. These factors influence gene function by affecting mRNA splicing pattern or by altering/eliminating protein function. Elucidating the genetic bases of diseases under the control of many genes is very challenging, and it is compounded by several factors, including host × pathogen × environment interactions. In this review, the genetic variations that underlie several diseases of livestock (under monogenic and polygenic control) are analyzed. Also, factors hampering research efforts toward identification of genetic influences on animal disease identification and control are highlighted. A better understanding of the factors analyzed could be better harnessed to effectively identify and control, genetically, livestock diseases. Finally, genetic control of animal diseases can reduce the costs associated with diseases, improve animal welfare, and provide healthy animal products to consumers, and should be given more attention. PMID:18350334
USDA-ARS?s Scientific Manuscript database
Transformation plasmid-derived insert number and insert site sequence in 55-1 line papaya derivatives Rainbow and SunUp was determined as part of a larger petition to allow its import into Japan (Suzuki, et al., 2007, 2008). Three insertions were detected by Southern analysis and their correspondin...
Fila-Danilow, Anna; Kucia, Krzysztof; Kowalczyk, Malgorzata; Owczarek, Aleksander; Paul-Samojedny, Monika; Borkowska, Paulina; Suchanek, Renata; Kowalski, Jan
2012-08-01
Changes in immunological system are one of dysfunctions reported in schizophrenia. Some changes based on an imbalance between Th1 and Th2 cytokines results from cytokine gene polymorphisms. Interleukin-4 gene (IL4) is considered as a potential candidate gene in schizophrenia association studies. The aim of the current case-control study was to examine whether the -590C/T (rs2243250) and -33C/T (rs2070874) IL4 gene polymorphisms are implicated in paranoid schizophrenia development in the Polish population. Genotyping of polymorphisms was performed by using PCR-RFLP technique. The genotypes and alleles distribution of both SNPs were analysed in patients (n = 182) and healthy individuals constituted the control group (n = 215). The connection between some clinical variables and studied polymorphisms has been examined as well. We did not revealed any association between the -590C/T and -33C/T polymorphisms and paranoid schizophrenia. In case of both SNPs the homozygous TT genotype was extremely rare. Both polymorphic sites of the IL4 gene were found to be in a very strong linkage disequilibrium. However we did not identify a haplotype predispose to paranoid schizophrenia. No associations were also observed between the clinical course and psychopathology of the disease and the genotypes of both analysed polymorphisms. Our results suggest that the polymorphisms -590C/T in IL4 gene promoter region and -33C/T in the 5'-UTR are not involved in the pathophysiology of paranoid schizophrenia in Polish residents.
Histopathology of tympanic membranes from patients with ventilation tubes.
Oktay, Mehmet Faruk; Tansuker, Hasan Deniz; Fukushima, Hisaki; Paparella, Michael M; Schachern, Patricia A; Cureoglu, Sebahattin
2018-06-01
To evaluate the histopathologic changes in tympanic membranes (TMs) with ventilation tubes (VTs). In this retrospective human temporal bone study our overall study group included 4 subgroups of TMs from deceased donors as follows: 24 with a history of VT insertion for chronic otitis media with effusion (COME-VT); 5 with a history of VT insertion for Meniere's disease (MD-VT); 33 without a history of VT insertion for chronic otitis media with effusion (COME); and 14 without a history of VT insertion for Meniere's disease (MD). We classified the extent of migration of the outer keratinized squamous epithelium onto the inner surface of TM perforations and noted the presence and location of tympanosclerosis, of atrophy, of perforation, and/or of cholesteatoma formation. Tympanosclerosis occurred in 14/24 TMs in the COME-VT subgroup; 2/5, MD-VT; 7/33, COME; and 0/14, MD. The VT insertion site was mostly in the anteroinferior (63%) quadrant of the TM; tympanosclerosis occurred more frequently in the posteroinferior (42%) and posterosuperior (33%) quadrants. We found no significant correlation between the location of tympanosclerosis and the VT insertion site (P>0.05). Atrophy occurred in 7/24 TMs in the COME-VT subgroup; 3/5, MD-VT; 8/33, COME; and 2/14, MD. We found no significant correlation between the location of atrophy and the VT insertion site; however, atrophy was located mostly in the anteroinferior quadrant (one of the most common VT insertion sites) of the TM. Regarding the ingrowth of keratinized epithelium, the mucocutanous junction was detected at any point at the inner surface of the TM in 50% of the specimens. We observed intratympanic cholesteatoma formation in 2/24 TMs in the COME-VT subgroup. TM changes due to VT insertion are more common than previously realized. Meticulous otomicroscopic evaluation of the TM is necessary during tympanomastoidectomies in order to prevent the intratympanic inclusion pearls and squamous epithelial ingrowth to prevent any further cholesteatoma formation. Copyright © 2017. Published by Elsevier B.V.
Kappa-casein polymorphisms among cattle breeds and bison herds
Cronin, M.A.; Cockett, N.
1993-01-01
We identified the HindIII restriction site polymorphism Of kappa-casein in cattle reported by Pinder et al. (Animal Genetics 22, 11, 1991) and found an additonal polymorphism (RsaI) in cattle and bison. The Hin dIII and Rsa I restriction sites were mapped and three haplotypes (alleles) were identified. Preliminary screening of 39 cattle and 71 bison revealed one allele restricted to cattle, one restricted to bison, and one shared by the species. No fixed allelic differences were observed among cattle breeds or among bison herds or subspecies.
Coppedè, Fabio; Lo Gerfo, Annalisa; Carlesi, Cecilia; Piazza, Selina; Mancuso, Michelangelo; Pasquali, Livia; Murri, Luigi; Migliore, Lucia; Siciliano, Gabriele
2010-02-01
Impairments in DNA repair enzymes have been observed in amyotrophic lateral sclerosis (ALS) tissues, particularly in the activity of the apurinic/apyrimidinic endonuclease 1 (APEX1). Moreover, it was suggested that the common APEX1 Asp148Glu polymorphism might be associated with ALS risk. To further address this question we performed the present study aimed at evaluating the contribution of the APEX1 Asp148Glu polymorphism in sporadic ALS (sALS) risk and clinical presentation, including age and site of onset and disease progression. We screened 134 sALS Italian patients and 129 matched controls for the presence of the APEX1 Asp148Glu polymorphism. No difference in APEX1 Asp148Glu allele and genotype frequencies was found between the groups, nor was the polymorphism associated with age and site of onset or disease progression. Present results do not support a role for the APEX1 Asp148Glu polymorphism in sALS pathogenesis in the Italian population.
Jia, Xianbo; Lin, Xinjian; Chen, Jichen
2017-11-02
Current genome walking methods are very time consuming, and many produce non-specific amplification products. To amplify the flanking sequences that are adjacent to Tn5 transposon insertion sites in Serratia marcescens FZSF02, we developed a genome walking method based on TAIL-PCR. This PCR method added a 20-cycle linear amplification step before the exponential amplification step to increase the concentration of the target sequences. Products of the linear amplification and the exponential amplification were diluted 100-fold to decrease the concentration of the templates that cause non-specific amplification. Fast DNA polymerase with a high extension speed was used in this method, and an amplification program was used to rapidly amplify long specific sequences. With this linear and exponential TAIL-PCR (LETAIL-PCR), we successfully obtained products larger than 2 kb from Tn5 transposon insertion mutant strains within 3 h. This method can be widely used in genome walking studies to amplify unknown sequences that are adjacent to known sequences.
Targeted gene insertion for molecular medicine.
Voigt, Katrin; Izsvák, Zsuzsanna; Ivics, Zoltán
2008-11-01
Genomic insertion of a functional gene together with suitable transcriptional regulatory elements is often required for long-term therapeutical benefit in gene therapy for several genetic diseases. A variety of integrating vectors for gene delivery exist. Some of them exhibit random genomic integration, whereas others have integration preferences based on attributes of the targeted site, such as primary DNA sequence and physical structure of the DNA, or through tethering to certain DNA sequences by host-encoded cellular factors. Uncontrolled genomic insertion bears the risk of the transgene being silenced due to chromosomal position effects, and can lead to genotoxic effects due to mutagenesis of cellular genes. None of the vector systems currently used in either preclinical experiments or clinical trials displays sufficient preferences for target DNA sequences that would ensure appropriate and reliable expression of the transgene and simultaneously prevent hazardous side effects. We review in this paper the advantages and disadvantages of both viral and non-viral gene delivery technologies, discuss mechanisms of target site selection of integrating genetic elements (viruses and transposons), and suggest distinct molecular strategies for targeted gene delivery.
NcoI and TaqI RFLPs for human M creatine kinase (CKM)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perryman, M.B.; Hejtmancik, J.F.; Ashizawa, Tetsuo
1988-09-12
Probe pHMCKUT contains a 135 bp cDNA fragment inserted into pGEM 3. The probe corresponds to nucleotides 1,201 to 1,336 located in the 3{prime} untranslated region of human M creatine kinase. The probe is specific for human M creatine kinase and does not hybridize to human B cretine kinase sequences. NcoI identifies a two allele polymorphism of a band at either 2.5 kb or 3.6 kb. TaqI identifies a two allele polymorphism at either 3.8 kb or 4.5 kb. Human M creatine has been localized to chromosome 19q. Autosomal co-dominant inheritance was shown in six informative Caucasian families.
Evaluation of two new STR loci 9q2h2 and wg3f12 in a Japanese population.
Mizutani, M; Huang, X L; Tamaki, K; Yoshimoto, T; Uchihi, R; Yamamoto, T; Katsumata, Y; Armour, J A
1999-09-01
Two short tandem repeat (STR) loci (9q2h2 and wg3f12) have been evaluated in a Japanese population. Ten and seven different alleles were observed in 9q2h2 and wg3f12 respectively. 9q2h2 displayed simple polymorphism in tetrameric repeat structure; by contrast, wg3f12 contained variable numbers of tetrameric repeats and a 30-bp deletion/insertion polymorphism. No "interalleles" were found. The expected heterozygosities of 9q2h2 and wg3fl2 were 0.749 and 0.574, respectively. No deviation from Hardy-Weinberg equilibrium was found.
Discovery of rare, diagnostic AluYb8/9 elements in diverse human populations.
Feusier, Julie; Witherspoon, David J; Scott Watkins, W; Goubert, Clément; Sasani, Thomas A; Jorde, Lynn B
2017-01-01
Polymorphic human Alu elements are excellent tools for assessing population structure, and new retrotransposition events can contribute to disease. Next-generation sequencing has greatly increased the potential to discover Alu elements in human populations, and various sequencing and bioinformatics methods have been designed to tackle the problem of detecting these highly repetitive elements. However, current techniques for Alu discovery may miss rare, polymorphic Alu elements. Combining multiple discovery approaches may provide a better profile of the polymorphic Alu mobilome. Alu Yb8/9 elements have been a focus of our recent studies as they are young subfamilies (~2.3 million years old) that contribute ~30% of recent polymorphic Alu retrotransposition events. Here, we update our ME-Scan methods for detecting Alu elements and apply these methods to discover new insertions in a large set of individuals with diverse ancestral backgrounds. We identified 5,288 putative Alu insertion events, including several hundred novel Alu Yb8/9 elements from 213 individuals from 18 diverse human populations. Hundreds of these loci were specific to continental populations, and 23 non-reference population-specific loci were validated by PCR. We provide high-quality sequence information for 68 rare Alu Yb8/9 elements, of which 11 have hallmarks of an active source element. Our subfamily distribution of rare Alu Yb8/9 elements is consistent with previous datasets, and may be representative of rare loci. We also find that while ME-Scan and low-coverage, whole-genome sequencing (WGS) detect different Alu elements in 41 1000 Genomes individuals, the two methods yield similar population structure results. Current in-silico methods for Alu discovery may miss rare, polymorphic Alu elements. Therefore, using multiple techniques can provide a more accurate profile of Alu elements in individuals and populations. We improved our false-negative rate as an indicator of sample quality for future ME-Scan experiments. In conclusion, we demonstrate that ME-Scan is a good supplement for next-generation sequencing methods and is well-suited for population-level analyses.
Eroğlu, Onur; Zileli, Rayif; Nalbant, M Ali; Ulucan, Korkut
2018-04-30
Studies to date showed the importance of alpha- actinin-3 (ACTN3) R577X and angiotensin converting enzyme (ACE) ID polymorphisms on determining athletic performance. Therefore, in this study, we aimed to examine polymorphisms given to Turkish athletes and compare them with sedentary individuals. Genomic DNAs were extracted from peripheral blood by using commercially available DNA isolation kit (Macherey-Nagel, NucleoSpin®, Germany). For this study, a total of 84 volunteers (23 national athletes, 27 amateur athletes and 34 sedentary controls) was recruited. ACE ID genotypes were determined by conventional polymerase chain reaction, and ACTN3 R577X polymorphisms by polymerase chain reaction- restriction fragment length polymorphism methodology. In ACTN3 R577X polymorphism, RX was the dominating genotype, and we detected no RR genotype in national athletes. (no RR genotype was detected in national athletes) X allele is more frequent in national athletes and R allele was more frequent in both amateur athletes and control group. II genotype was more frequent in national athletes and in control group, whereas DD genotype was more frequent in amateur athletes for ACE ID polymorphism. When we consider alleles, D allele was found more frequently in amateur athletes and control group whereas I allele was more frequent in national athletes in ACE ID polymorphism. For ACTN3, X allele was superior to R allele. ACTN3 R577X and ACE ID polymorphisms were important biomarkers in determining athletic performance. However, our results in Turkish athletes suggest that ACE D allele and ACTN3 X alleles may be beneficial to athletes potentially, regardless of the distance they perform.
Recombinational Cloning Using Gateway and In-Fusion Cloning Schemes
Throop, Andrea L.; LaBaer, Joshua
2015-01-01
The comprehensive study of protein structure and function, or proteomics, depends on the obtainability of full-length cDNAs in species-specific expression vectors and subsequent functional analysis of the expressed protein. Recombinational cloning is a universal cloning technique based on site-specific recombination that is independent of the insert DNA sequence of interest, which differentiates this method from the classical restriction enzyme-based cloning methods. Recombinational cloning enables rapid and efficient parallel transfer of DNA inserts into multiple expression systems. This unit summarizes strategies for generating expression-ready clones using the most popular recombinational cloning technologies, including the commercially available Gateway® (Life Technologies) and In-Fusion® (Clontech) cloning technologies. PMID:25827088
Nadjar-Boger, Elisabeth; Funkenstein, Bruria
2011-02-01
Myostatin (MSTN) is a member of the transforming growth factor-ß superfamily that functions as a negative regulator of skeletal muscle development and growth in mammals. Fish express at least two genes for MSTN: MSTN-1 and MSTN-2. To date, MSTN-2 promoters have been cloned only from salmonids and zebrafish. Here we described the cloning and sequence analysis of MSTN-2 gene and its 5' flanking region in the marine fish Sparus aurata (saMSTN-2). We demonstrate the existence of three alleles of the promoter and three alleles of the first intron. Sequence comparison of the promoter region in the three alleles revealed that although the sequences of the first 1050 bp upstream of the translation start site are almost identical in the three alleles, a substantial sequence divergence is seen further upstream. Careful sequence analysis of the region upstream of the first 1050 bp in the three alleles identified several elements that appear to be repeated in some or all sequences, at different positions. This suggests that the promoter region of saMSTN-2 has been subjected to various chromosomal rearrangements during the course of evolution, reflecting either insertion or deletion events. Screening of several genomic DNA collections indicated differences in allele frequency, with allele 'b' being the most abundant, followed by allele 'c', whereas allele 'a' is relatively rare. Sequence analysis of saMSTN-2 gene also revealed polymorphism in the first intron, identifying three alleles. The length difference in alleles '1R' and '2R' of the first intron is due to the presence of one or two copies of a repeated block of approximately 150 bp, located at the 5' end of the first intron. The third allele, '4R', has an additional insertion of 323 bp located 116 bp upstream of the 3' end of the first intron. Analysis of several DNA collections showed that the '2R' allele is the most common, followed by the '4R' allele, whereas the '1R' allele is relatively rare. Progeny analysis of a full-sib family showed a Mendelian mode of inheritance of the two genetic loci. No clear association was found between the two genetic markers and growth rate. These results show for the first time a substantial degree of polymorphism in both the promoter and first intron of MSTN-2 gene in a perciform fish species which points to chromosomal rearrangements that took place during evolution.
Barroso, G.; Blesa, S.; Labarere, J.
1995-01-01
We used restriction fragment length polymorphisms to examine mitochondrial genome rearrangements in 36 wild strains of the cultivated basidiomycete Agrocybe aegerita, collected from widely distributed locations in Europe. We identified two polymorphic regions within the mitochondrial DNA which varied independently: one carrying the Cox II coding sequence and the other carrying the Cox I, ATP6, and ATP8 coding sequences. Two types of mutations were responsible for the restriction fragment length polymorphisms that we observed and, accordingly, were involved in the A. aegerita mitochondrial genome evolution: (i) point mutations, which resulted in strain-specific mitochondrial markers, and (ii) length mutations due to genome rearrangements, such as deletions, insertions, or duplications. Within each polymorphic region, the length differences defined only two mitochondrial types, suggesting that these length mutations were not randomly generated but resulted from a precise rearrangement mechanism. For each of the two polymorphic regions, the two molecular types were distributed among the 36 strains without obvious correlation with their geographic origin. On the basis of these two polymorphisms, it is possible to define four mitochondrial haplotypes. The four mitochondrial haplotypes could be the result of intermolecular recombination between allelic forms present in the population long enough to reach linkage equilibrium. All of the 36 dikaryotic strains contained only a single mitochondrial type, confirming the previously described mitochondrial sorting out after cytoplasmic mixing in basidiomycetes. PMID:16534984
Zalsman, Gil; Frisch, Amos; Baruch-Movshovits, Ruth; Sher, Leo; Michaelovsky, Elena; King, Robert A; Fischel, Tsvi; Hermesh, Haggai; Goldberg, Pablo; Gorlyn, Marianne; Misgav, Sagit; Apter, Alan; Tyano, Sam; Weizman, Abraham
2005-01-01
Suicidal behavior runs in families and is partially genetically determined. Since greater serotonin 5-HT(2A) receptor binding has been reported in postmortem brain and platelets of suicide victims, the 5-HT(2A) receptor gene polymorphism T102C became one of the candidate sites in the study of suicide and impulsive-aggressive traits. However, studies that examined the association of this polymorphism with suicidality have contradictory results. This study used a family-based method and one homogenous ethnic group to overcome ethnic stratification in order to test this association. Thirty families of inpatient adolescents from Jewish Ashkenazi origin, with a recent suicide attempt, were genotyped. All subjects were interviewed for clinical diagnosis, depressive and impulsive-aggressive traits and demographic data. Allele frequencies were assessed using the Haplotype Relative Risk method for trios. No difference was found in allelic distribution between transmitted and non-transmitted alleles. There was no significant association of genotype with any of the clinical traits These preliminary results suggest that the 5-HT(2A) T102C polymorphism is unlikely to be associated with suicidal behavior and related traits in adolescent suicide attempters.
Rakocevic, Alexandra; Mondy, Samuel; Tirichine, Leïla; Cosson, Viviane; Brocard, Lysiane; Iantcheva, Anelia; Cayrel, Anne; Devier, Benjamin; Abu El-Heba, Ghada Ahmed; Ratet, Pascal
2009-11-01
We have identified an active Medicago truncatula copia-like retroelement called Medicago RetroElement1-1 (MERE1-1) as an insertion in the symbiotic NSP2 gene. MERE1-1 belongs to a low-copy-number family in the sequenced Medicago genome. These copies are highly related, but only three of them have a complete coding region and polymorphism exists between the long terminal repeats of these different copies. This retroelement family is present in all M. truncatula ecotypes tested but also in other legume species like Lotus japonicus. It is active only during tissue culture in both R108 and Jemalong Medicago accessions and inserts preferentially in genes.
Vivero, Rafael José; Contreras-Gutiérrez, Maria Angélica; Bejarano, Eduar Elías
2007-09-01
Lutzomyia sand flies are involved in the transmission of the parasite Leishmania spp. in America. The taxonomy of these vectors is traditionally based on morphological features of the adult stage, particularly the paired structures of the head and genitalia. Although these characters are useful to distinguish most species of Lutzomyia, morphological identification may be complicated by the similarities within subgenera and species group. To evaluate the utility of mitochondrial serine transfer RNA tRNA Ser for taxonomic identification of Lutzomyia. Seven sand fly species, each representing one of the 27 taxonomic subdivisions in genus Lutzomyia, were analyzed including L. trinidadensis (Oswaldoi group), L. (Psychodopygus) panamensis, L.(Micropygomyia) cayennensis cayennensis, L. dubitans (Migonei group), L. (Lutzomyia) gomezi, L. rangeliana (ungrouped) and L. evansi (Verrucarum group). The mitochondrial tRNA Ser gene, flanked by the cytochrome b and NAD dehydrogenase subunit one genes, was extracted, amplified and sequenced from each specimen. Secondary structure of the tRNA Ser was predicted by comparisons with previously described homologous structures from other dipteran species. The tRNA Ser gene ranged in size from 66 base pairs in L. gomezi to 69 base pairs in L. trinidadensis. Fourteen polymorphic sites, including four insertion-deletion events, were observed in the aligned 70 nucleotide positions. The majority of the substitutions were located in the dihydrouridine, ribothymidine-pseudouridine-cytosine and variable loops, as well as in the basal extreme of the anticodon arm. Changes of primary sequence of the tRNASer provided useful molecular characters for taxonomic identification of the sand fly species under consideration.
Wu, Eugene Y.; Beese, Lorena S.
2011-01-01
To achieve accurate DNA synthesis, DNA polymerases must rapidly sample and discriminate against incorrect nucleotides. Here we report the crystal structure of a high fidelity DNA polymerase I bound to DNA primer-template caught in the act of binding a mismatched (dG:dTTP) nucleoside triphosphate. The polymerase adopts a conformation in between the previously established “open” and “closed” states. In this “ajar” conformation, the template base has moved into the insertion site but misaligns an incorrect nucleotide relative to the primer terminus. The displacement of a conserved active site tyrosine in the insertion site by the template base is accommodated by a distinctive kink in the polymerase O helix, resulting in a partially open ternary complex. We suggest that the ajar conformation allows the template to probe incoming nucleotides for complementarity before closure of the enzyme around the substrate. Based on solution fluorescence, kinetics, and crystallographic analyses of wild-type and mutant polymerases reported here, we present a three-state reaction pathway in which nucleotides either pass through this intermediate conformation to the closed conformation and catalysis or are misaligned within the intermediate, leading to destabilization of the closed conformation. PMID:21454515
Zhong, J; Wu, F-C; Qiu, P; Dai, L-J
2016-08-12
To study the levels of genetic diversity, and population structure, of Houttuynia cordata Thunb, the genetic background and relationships of populations were analyzed in terms of environmental factors. The genetic diversity and population structure of H. cordata were investigated using sequence-related amplified polymorphisms and correlation with environmental factors was analyzed using the SPSS software. Two thousand one hundred sixty-three sites were amplified from 41 pairs of primers, 1825 of which were polymorphic, and the percentage of polymorphic loci was 84.37%; the percentage of polymorphic sites was 72.14 and 67.77% at the species and population level, respectively. The observed number of alleles was 1.52 and 1.30 at species and population level, respectively. The effective number of alleles was 1.38 and 1.24 at species and population level, respectively. The Nei's diversity was 0.26 and 0.15 at species and population level, respectively. The Shannon's information index was 0.87 and 0.63 at species and population level, respectively. The genetic differentiation coefficient of populations was 0.51, and 12 populations were divided into three classes based on D = 0.20; the genetic diversities of different populations are correlated at different significance levels (P < 0.05) with environmental factors. Genetic differentiation existed among populations and the populations exhibited heteroplasmy.
El-Hazmi, Mohsen Af; Warsy, Arjumand S
2003-01-01
Several studies have been carried out to investigate the insertion/deletion (I/D) polymorphism of angiotensin-converting enzyme (ACE) in obese and normal weight individuals, often with contradictory results in different populatios. In some studies, the DD genotype occurs at a high frequency in obesity, while in others no association has been demonstrated. Since obesity and overweight are of frequent occurrence in the Saudi population, we initiated this study to investigate the I/D polymorphism of ACE in obese, overweight and normal weight Saudis. The study group included 457 Saudi males and females. The height and weight were measured and body mass index (BMI) was calculated. Based on the BMI value, the total study population was classified as normal, overweight and obese. A total of 117 obese (BMI >30 (kg/m(2))), 185 overweight (BMI=25-29.9 (kg/m(2))) and 155 normal weight individuals (BMI< (kg/m (2)) were enrolled. Polymerase chain reaction (PCR) and agarose gel electrophoresis were used to study the ACE polymorphism. For the deletion (D) form, a 190 bp and for the insertion (I) form, 490 bp DNA fragment were obtained on 2% agarose gel electrophoresis. The frequency of DD genotype was 76.9% in the obese, and 73.5% in the overweight individuals, compared to 19.66% and 24.86% of the ID genotype in the obese and overweight, respectively. Among the normal weight individuals, the frequency was significantly lower for DD and higher for the ID genotype, i.e., 58.7% for DD and 40% for ID. The allele frequencies in the obese were 0.867 and 0.133 for the D and I alleles, respectively. While in the overweight, the frequencies were 0.859 and 0.141 for these alleles, respectively, compared to 0.787 and 0.213 in the normal weight individuals. The DD genotype and D allele occur at a high frequency in Saudi overweight and obese individuals, and may have some role in fat accumulation by affecting metabolic pathways of fat, thus leading to the development of overweight and obesity.
Jo, Ick Hyun; Kim, Young Chang; Kim, Dong Hwi; Kim, Kee Hong; Hyun, Tae Kyung; Ryu, Hojin; Bang, Kyong Hwan
2017-10-01
The development of molecular markers is one of the most useful methods for molecular breeding and marker-based molecular associated selections. Even though there is less information on the reference genome, molecular markers are indispensable tools for determination of genetic variation and identification of species with high levels of accuracy and reproducibility. The demand for molecular approaches for marker-based breeding and genetic discriminations in Panax species has greatly increased in recent times and has been successfully applied for various purposes. However, owing to the existence of diverse molecular techniques and differences in their principles and applications, there should be careful consideration while selecting appropriate marker types. In this review, we outline the recent status of different molecular marker applications in ginseng research and industrial fields. In addition, we discuss the basic principles, requirements, and advantages and disadvantages of the most widely used molecular markers, including restriction fragment length polymorphism, random amplified polymorphic DNA, sequence tag sites, simple sequence repeats, and single nucleotide polymorphisms.
Katz, B Z; Niederman, J C; Olson, B A; Miller, G
1988-02-01
DNA restriction fragment length polymorphisms of Epstein-Barr virus (EBV) DNA were used as a molecular epidemiological tool to study multiple isolates of virus from the same and different individuals. We studied 35 EBV isolates: 19 from seven immunocompromised children and 16 from seven college students with mononucleosis. Analysis of the fragment length polymorphisms in this collection of isolates permitted several conclusions. Sites of polymorphism were most often encountered in regions with repetitive DNA. Epidemiologically unrelated patients harbored viruses that could be readily distinguished; by contrast, two infants and their mothers harbored similar viruses. Isolates from different sites in the same patient were similar. Variations between different clinical isolates of EBV mimic those found between different laboratory strains of the virus. Fragment length polymorphisms thus provide a useful marker for studying transmission and pathogenesis of EBV infections.
The infinite sites model of genome evolution.
Ma, Jian; Ratan, Aakrosh; Raney, Brian J; Suh, Bernard B; Miller, Webb; Haussler, David
2008-09-23
We formalize the problem of recovering the evolutionary history of a set of genomes that are related to an unseen common ancestor genome by operations of speciation, deletion, insertion, duplication, and rearrangement of segments of bases. The problem is examined in the limit as the number of bases in each genome goes to infinity. In this limit, the chromosomes are represented by continuous circles or line segments. For such an infinite-sites model, we present a polynomial-time algorithm to find the most parsimonious evolutionary history of any set of related present-day genomes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamilton, Brian S.; Sun, Xiangjie; Chung, Changik
A critical feature of highly pathogenic avian influenza viruses (H5N1 and H7N7) is the efficient intracellular cleavage of the hemagglutinin (HA) protein. H7N7 viruses also exist in equine species, and a unique feature of the equine H7N7 HA is the presence of an eleven amino acid insertion directly N-terminal to a tetrabasic cleavage site. Here, we show that three histidine residues within the unique insertion of the equine H7N7 HA are essential for intracellular cleavage. An asparagine residue within the insertion-derived glycosylation site was also found to be essential for intracellular cleavage. The presence of the histidine residues also appearmore » to be involved in triggering fusion, since mutation of the histidine residues resulted in a destabilizing effect. Importantly, the addition of a tetrabasic site and the eleven amino acid insertion conferred efficient intracellular cleavage to the HA of an H7N3 low pathogenicity avian influenza virus. Our studies show that acquisition of the eleven amino acid insertion offers an alternative mechanism for intracellular cleavage of influenza HA.« less
The Population History of Endogenous Retroviruses in Mule Deer (Odocoileus hemionus)
2014-01-01
Mobile elements are powerful agents of genomic evolution and can be exceptionally informative markers for investigating species and population-level evolutionary history. While several studies have utilized retrotransposon-based insertional polymorphisms to resolve phylogenies, few population studies exist outside of humans. Endogenous retroviruses are LTR-retrotransposons derived from retroviruses that have become stably integrated in the host genome during past infections and transmitted vertically to subsequent generations. They offer valuable insight into host-virus co-evolution and a unique perspective on host evolutionary history because they integrate into the genome at a discrete point in time. We examined the evolutionary history of a cervid endogenous gammaretrovirus (CrERVγ) in mule deer (Odocoileus hemionus). We sequenced 14 CrERV proviruses (CrERV-in1 to -in14), and examined the prevalence and distribution of 13 proviruses in 262 deer among 15 populations from Montana, Wyoming, and Utah. CrERV absence in white-tailed deer (O. virginianus), identical 5′ and 3′ long terminal repeat (LTR) sequences, insertional polymorphism, and CrERV divergence time estimates indicated that most endogenization events occurred within the last 200000 years. Population structure inferred from CrERVs (F ST = 0.008) and microsatellites (θ = 0.01) was low, but significant, with Utah, northwestern Montana, and a Helena herd being particularly differentiated. Clustering analyses indicated regional structuring, and non-contiguous clustering could often be explained by known translocations. Cluster ensemble results indicated spatial localization of viruses, specifically in deer from northeastern and western Montana. This study demonstrates the utility of endogenous retroviruses to elucidate and provide novel insight into both ERV evolutionary history and the history of contemporary host populations. PMID:24336966
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chain, Patrick S; Hu, Ping; Malfatti, Stephanie
2006-01-01
Yersinia pestis, the causative agent of bubonic and pneumonic plagues, has undergone detailed study at the molecular level. To further investigate the genomic diversity among this group and to help characterize lineages of the plague organism that have no sequenced members, we present here the genomes of two isolates of the ''classical'' antiqua biovar, strains Antiqua and Nepal516. The genomes of Antiqua and Nepal516 are 4.7 Mb and 4.5 Mb and encode 4,138 and 3,956 open reading frames, respectively. Though both strains belong to one of the three classical biovars, they represent separate lineages defined by recent phylogenetic studies. Wemore » compare all five currently sequenced Y. pestis genomes and the corresponding features in Yersinia pseudotuberculosis. There are strain-specific rearrangements, insertions, deletions, single nucleotide polymorphisms, and a unique distribution of insertion sequences. We found 453 single nucleotide polymorphisms in protein-coding regions, which were used to assess the evolutionary relationships of these Y. pestis strains. Gene reduction analysis revealed that the gene deletion processes are under selective pressure, and many of the inactivations are probably related to the organism's interaction with its host environment. The results presented here clearly demonstrate the differences between the two biovar antiqua lineages and support the notion that grouping Y. pestis strains based strictly on the classical definition of biovars (predicated upon two biochemical assays) does not accurately reflect the phylogenetic relationships within this species. A comparison of four virulent Y. pestis strains with the human-avirulent strain 91001 provides further insight into the genetic basis of virulence to humans.« less
The population history of endogenous retroviruses in mule deer (Odocoileus heminous)
Kamath, Pauline L.; Elleder, Daniel; Bao, Le; Cross, Paul C.; Powell, John H.; Poss, Mary
2013-01-01
Mobile elements are powerful agents of genomic evolution and can be exceptionally informative markers for investigating species and population-level evolutionary history. While several studies have utilized retrotransposon-based insertional polymorphisms to resolve phylogenies, few population studies exist outside of humans. Endogenous retroviruses are LTR-retrotransposons derived from retroviruses that have become stably integrated in the host genome during past infections and transmitted vertically to subsequent generations. They offer valuable insight into host-virus co-evolution and a unique perspective on host evolutionary history because they integrate into the genome at a discrete point in time. We examined the evolutionary history of a cervid endogenous gammaretrovirus (CrERVγ) in mule deer (Odocoileus hemionus). We sequenced 14 CrERV proviruses (CrERV-in1 to -in14), and examined the prevalence and distribution of 13 proviruses in 262 deer among 15 populations from Montana, Wyoming, and Utah. CrERV absence in white-tailed deer (O. virginianus), identical 5′ and 3′ long terminal repeat (LTR) sequences, insertional polymorphism, and CrERV divergence time estimates indicated that most endogenization events occurred within the last 200000 years. Population structure inferred from CrERVs (F ST = 0.008) and microsatellites (θ = 0.01) was low, but significant, with Utah, northwestern Montana, and a Helena herd being particularly differentiated. Clustering analyses indicated regional structuring, and non-contiguous clustering could often be explained by known translocations. Cluster ensemble results indicated spatial localization of viruses, specifically in deer from northeastern and western Montana. This study demonstrates the utility of endogenous retroviruses to elucidate and provide novel insight into both ERV evolutionary history and the history of contemporary host populations.
Ma, Ruilin; Shen, Chunmei; Wei, Yuanyuan; Jin, Xiaoye; Guo, Yuxin; Mu, Yuling; Sun, Siqi; Chen, Chong; Cui, Wei; Wei, Zhaoming; Lian, Zhenmin
2018-06-20
The present study investigated the genetic diversities of 30 autosomal insertion and deletion (InDel) loci of Investigator DIPplex kit (Qiagen) in Chinese Salar ethnic minority and explored the genetic relationships between the studied Salar group and other populations. The allelic frequencies of deletion alleles at the 30 InDel loci were in the range of 0.1739 (HLD64) to 0.8478 (HLD39). The discrimination power, polymorphism information content and probability of exclusion ranged from 0.4101 (HLD39) to 0.6447 (HLD136), 0.2247 (HLD39) to 0.3750 (HLD92) and 0.0400 (HLD39) to 0.2806 (HLD92), respectively. The observed and expected heterozygosity were in the range of 0.2348 (HLD39) to 0.5913 (HLD92), and 0.2580 (HLD39) to 0.5000 (HLD92), respectively. The cumulative discrimination power and probability of exclusion of the 30 loci reached 0.999999999993418 and 0.99039, respectively. The results of population genetic differentiation comparisons revealed that Salar group had similar allele distributions with Qinghai Tibetan, Xibe and Yi groups. Population Bayesian cluster analysis showed that there were similar ancestry components between Salar group and most Chinese populations. Besides, the principal components analysis and phylogenetic reconstructions further indicated that Salar group had intimate genetic relationships with Qinghai Tibetan and Xibe groups. In short, the results of the current studies indicated the genetic distributions of the 30 InDel loci in Salar group were relatively high genetic polymorphisms, which could be used in forensic individual identifications and as a supplementary tool for complex paternity testing. Copyright © 2018 Elsevier B.V. All rights reserved.
Neves-Pereira, Maria; Mundo, Emanuela; Muglia, Pierandrea; King, Nicole; Macciardi, Fabio; Kennedy, James L.
2002-01-01
Bipolar disorder (BP) is a severe psychiatric disease, with a strong genetic component, that affects 1% of the population worldwide and is characterized by recurrent episodes of mania and depression. Brain-derived neurotrophic factor (BDNF) has been implicated in the pathogenesis of mood disorders, and the aim of the present study was to test for the presence of linkage disequilibrium between two polymorphisms in the BDNF gene and BP in 283 nuclear families. Family-based association test (FBAT) results for the dinucleotide repeat (GT)N polymorphism at position −1040 bp showed that allele A3 was preferentially transmitted to the affected individuals (Z=2.035 and P=.042). FBAT results for the val66met SNP showed a significant association for allele G (Z=3.415 and P=.00064). Transmission/disequilibrium test (TDT) haplotype analysis showed a significant result for the 3-G allele combination (P=.000394), suggesting that a DNA variant in the vicinity of the BDNF locus confers susceptibility to BP. Given that there is no direct evidence that either of the polymorphisms we examined alters function, it is unlikely that the actual risk-conferring allele is from these two sites. Rather, the causative site is likely nearby and in linkage disequilibrium with the 3-G haplotype that we have identified. PMID:12161822
The insertional history of an active family of L1 retrotransposons in humans.
Boissinot, Stéphane; Entezam, Ali; Young, Lynn; Munson, Peter J; Furano, Anthony V
2004-07-01
As humans contain a currently active L1 (LINE-1) non-LTR retrotransposon family (Ta-1), the human genome database likely provides only a partial picture of Ta-1-generated diversity. We used a non-biased method to clone Ta-1 retrotransposon-containing loci from representatives of four ethnic populations. We obtained 277 distinct Ta-1 loci and identified an additional 67 loci in the human genome database. This collection represents approximately 90% of the Ta-1 population in the individuals examined and is thus more representative of the insertional history of Ta-1 than the human genome database, which lacked approximately 40% of our cloned Ta-1 elements. As both polymorphic and fixed Ta-1 elements are as abundant in the GC-poor genomic regions as in ancestral L1 elements, the enrichment of L1 elements in GC-poor areas is likely due to insertional bias rather than selection. Although the chromosomal distribution of Ta-1 inserts is generally a function of chromosomal length and gene density, chromosome 4 significantly deviates from this pattern and has been much more hospitable to Ta-1 insertions than any other chromosome. Also, the intra-chromosomal distribution of Ta-1 elements is not uniform. Ta-1 elements tend to cluster, and the maximal gaps between Ta-1 inserts are larger than would be expected from a model of uniform random insertion. Copyright 2004 Cold Spring Harbor Laboratory Press ISSN
Quantifying the Number of Independent Organelle DNA Insertions in Genome Evolution and Human Health
Martin, William F.
2017-01-01
Fragments of organelle genomes are often found as insertions in nuclear DNA. These fragments of mitochondrial DNA (numts) and plastid DNA (nupts) are ubiquitous components of eukaryotic genomes. They are, however, often edited out during the genome assembly process, leading to systematic underestimation of their frequency. Numts and nupts, once inserted, can become further fragmented through subsequent insertion of mobile elements or other recombinational events that disrupt the continuity of the inserted sequence relative to the genuine organelle DNA copy. Because numts and nupts are typically identified through sequence comparison tools such as BLAST, disruption of insertions into smaller fragments can lead to systematic overestimation of numt and nupt frequencies. Accurate identification of numts and nupts is important, however, both for better understanding of their role during evolution, and for monitoring their increasingly evident role in human disease. Human populations are polymorphic for 141 numt loci, five numts are causal to genetic disease, and cancer genomic studies are revealing an abundance of numts associated with tumor progression. Here, we report investigation of salient parameters involved in obtaining accurate estimates of numt and nupt numbers in genome sequence data. Numts and nupts from 44 sequenced eukaryotic genomes reveal lineage-specific differences in the number, relative age and frequency of insertional events as well as lineage-specific dynamics of their postinsertional fragmentation. Our findings outline the main technical parameters influencing accurate identification and frequency estimation of numts in genomic studies pertinent to both evolution and human health. PMID:28444372
Bonanno, Ludivine; Loukiadis, Estelle; Mariani-Kurkdjian, Patricia; Oswald, Eric; Garnier, Lucille; Michel, Valérie
2015-01-01
Shiga toxin-producing Escherichia coli (STEC) is a food-borne pathogen that may be responsible for severe human infections. Only a limited number of serotypes, including O26:H11, are involved in the majority of serious cases and outbreaks. The main virulence factors, Shiga toxins (Stx), are encoded by bacteriophages. Seventy-four STEC O26:H11 strains of various origins (including human, dairy, and cattle) were characterized for their stx subtypes and Stx phage chromosomal insertion sites. The majority of food and cattle strains possessed the stx1a subtype, while human strains carried mainly stx1a or stx2a. The wrbA and yehV genes were the main Stx phage insertion sites in STEC O26:H11, followed distantly by yecE and sbcB. Interestingly, the occurrence of Stx phages inserted in the yecE gene was low in dairy strains. In most of the 29 stx-negative E. coli O26:H11 strains also studied here, these bacterial insertion sites were vacant. Multilocus sequence typing of 20 stx-positive or stx-negative E. coli O26:H11 strains showed that they were distributed into two phylogenetic groups defined by sequence type 21 (ST21) and ST29. Finally, an EspK-carrying phage was found inserted in the ssrA gene in the majority of the STEC O26:H11 strains but in only a minority of the stx-negative E. coli O26:H11 strains. The differences in the stx subtypes and Stx phage insertion sites observed in STEC O26:H11 according to their origin might reflect that strains circulating in cattle and foods are clonally distinct from those isolated from human patients. PMID:25819955
Sequence variations of the bovine prion protein gene (PRNP) in native Korean Hanwoo cattle
Choi, Sangho
2012-01-01
Bovine spongiform encephalopathy (BSE) is one of the fatal neurodegenerative diseases known as transmissible spongiform encephalopathies (TSEs) caused by infectious prion proteins. Genetic variations correlated with susceptibility or resistance to TSE in humans and sheep have not been reported for bovine strains including those from Holstein, Jersey, and Japanese Black cattle. Here, we investigated bovine prion protein gene (PRNP) variations in Hanwoo cattle [Bos (B.) taurus coreanae], a native breed in Korea. We identified mutations and polymorphisms in the coding region of PRNP, determined their frequency, and evaluated their significance. We identified four synonymous polymorphisms and two non-synonymous mutations in PRNP, but found no novel polymorphisms. The sequence and number of octapeptide repeats were completely conserved, and the haplotype frequency of the coding region was similar to that of other B. taurus strains. When we examined the 23-bp and 12-bp insertion/deletion (indel) polymorphisms in the non-coding region of PRNP, Hanwoo cattle had a lower deletion allele and 23-bp del/12-bp del haplotype frequency than healthy and BSE-affected animals of other strains. Thus, Hanwoo are seemingly less susceptible to BSE than other strains due to the 23-bp and 12-bp indel polymorphisms. PMID:22705734
Dhandapani, Mohanapriya Chinambedu; Venkatesan, Vettriselvi; Rengaswamy, Nammalwar Bollam; Gowrishankar, Kalpana; Nageswaran, Prahlad; Perumal, Venkatachalam
2015-08-01
The purpose of the study was to investigate the distribution of insertion/deletion (I/D) polymorphisms of the angiotensin-converting enzyme (ACE) gene and three exonic polymorphisms of the multidrug resistance 1 (MDR1) gene (C3435T, C1236T, and G2677T) in children diagnosed with idiopathic nephrotic syndrome (INS). The study group consisted of 100 healthy controls and 150 INS patients, of which 50 were steroid resistant. Genomic DNA from blood samples was isolated from both of these groups and genotyping of the ACE and MDR1 genes was performed by polymerase chain reaction (PCR) using specific primers. There was no significant difference observed in the genotypic distribution and D allele frequency of the ACE gene. The two single-nucleotide polymorphisms (SNPs), C1236T and C3435T, of the MDR1 gene showed no significance, whereas the SNP G2677T/A was significantly associated with the genotypes GT and GA of the MDR1 gene, indicating it may be a potential marker to detect drug resistance. Screening these polymorphisms will pave the way to better understand the molecular mechanisms of the disease, which may be useful in developing targeted therapies for INS patients.
Zhang, Ya-Feng; Wang, Hong; Cheng, Qiong; Qin, Ling; Tang, Nelson Ls; Leung, Ping-Chong; Kwok, Timothy Cy
2017-01-01
In this study, we set out to investigate the relationship between angiotensin-converting enzyme ( ACE) I/D polymorphism, serum ACE activity and bone mineral density (BMD) in older Chinese. A standardized, structured, face-to-face interview was performed to collect demographic information. BMD was measured using dual-energy X-ray absorptiometry (DXA). I/D genotypes of ACE were determined by polymerase chain reaction (PCR) amplification. Serum ACE activity was determined photometrically by a commercially available kinetic kit. Multiple linear regression analysis was used to examine the relationship between ACE I/D polymorphism, serum ACE activity and BMD. A total of 1567 males and 1760 females were selected for analyzing the relationship between ACE I/D polymorphism and BMD. There was no significant difference in spine BMD, total hip BMD and femur neck BMD among different ACE I/D genotypes both in males and females. A total of 1699 males and 1739 females were selected for analyzing the relationship between serum ACE activity and BMD. There was also no significant difference in spine BMD, total hip BMD and femur neck BMD among different serum ACE activity groups both in males and females. There was no relationship between ACE I/D polymorphism, serum ACE activity and BMD in older Chinese.
Chiou, Terry Ting-Yu; Lee, Jong-Jer; Wang, Ming-Chung; Chung, Min-Shien; Pan, Lin-Lin; Hsieh, Ching-Jung; Huang, Siang-Ting; Chang, Hsueh-Wen; Yang, Kuender D; Lee, Chien-Te; Liu, Rue-Tsuan
2015-04-01
Anemia is prevalent but under-recognized in patients with diabetes mellitus (DM). Genetic variants in angiotensin-converting enzyme (ACE), tumor necrosis factor-alpha (TNF-α) and erythropoietin (EPO) have been associated with diabetic nephropathy. In the present study, we investigated the associations between anemia and polymorphisms in EPO promoter (rs1617640), TNF-α G-308A and ACE Insertion/Deletion in Chinese patients with type 2 diabetes. Polymorphisms in ACE, TNF-α and EPO were genotyped in 1142 patients. Anemia was defined as hemoglobin (Hb) levels below 12 g/dL for women and 13 g/dL for men. 286 (25%) patients had anemia. Patients with anemia were older, had longer duration of diabetes, worse renal function and more albuminuria. ACE Insertion/Deletion and TNF-a G-308A were not associated with anemia. The frequencies of EPO polymorphism (rs1617640) were significantly different between anemic and nonanemic patients. Patients with TT genotype had higher prevalence of anemia than those with TG and GG. Regression analysis identified EPO SNP, duration of DM, serum albumin, albuminuria and renal function independently associated with anemia. After adjusting for multiple variables, TT and TG genotypes were associated with 3-5-fold increased risk for anemia compared to GG. The EPO genotype in Chinese patients with type 2 diabetes is associated with anemia and may help to identify those at risk. Further evaluation of its effect on clinical outcomes in prospective studies may be useful to predict the outcomes of erythropoiesis stimulating therapy, and to individualize anemia management. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Association of insertion-deletions polymorphisms with colorectal cancer risk and clinical features
Marques, Diego; Ferreira-Costa, Layse Raynara; Ferreira-Costa, Lorenna Larissa; Correa, Romualdo da Silva; Borges, Aline Maciel Pinheiro; Ito, Fernanda Ribeiro; Ramos, Carlos Cesar de Oliveira; Bortolin, Raul Hernandes; Luchessi, André Ducati; Ribeiro-dos-Santos, Ândrea; Santos, Sidney; Silbiger, Vivian Nogueira
2017-01-01
AIM To investigate the association between 16 insertion-deletions (INDEL) polymorphisms, colorectal cancer (CRC) risk and clinical features in an admixed population. METHODS One hundred and forty patients with CRC and 140 cancer-free subjects were examined. Genomic DNA was extracted from peripheral blood samples. Polymorphisms and genomic ancestry distribution were assayed by Multiplex-PCR reaction, separated by capillary electrophoresis on the ABI 3130 Genetic Analyzer instrument and analyzed on GeneMapper ID v3.2. Clinicopathological data were obtained by consulting the patients’ clinical charts, intra-operative documentation, and pathology scoring. RESULTS Logistic regression analysis showed that polymorphism variations in IL4 gene was associated with increased CRC risk, while TYMS and UCP2 genes were associated with decreased risk. Reference to anatomical localization of tumor Del allele of NFKB1 and CASP8 were associated with more colon related incidents than rectosigmoid. In relation to the INDEL association with tumor node metastasis (TNM) stage risk, the Ins alleles of ACE, HLAG and TP53 (6 bp INDEL) were associated with higher TNM stage. Furthermore, regarding INDEL association with relapse risk, the Ins alleles of ACE, HLAG, and UGT1A1 were associated with early relapse risk, as well as the Del allele of TYMS. Regarding INDEL association with death risk before 10 years, the Ins allele of SGSM3 and UGT1A1 were associated with death risk. CONCLUSION The INDEL variations in ACE, UCP2, TYMS, IL4, NFKB1, CASP8, TP53, HLAG, UGT1A1, and SGSM3 were associated with CRC risk and clinical features in an admixed population. These data suggest that this cancer panel might be useful as a complementary tool for better clinical management, and more studies need to be conducted to confirm these findings. PMID:29085228
Zhao, Linlu; Bracken, Michael B; Dewan, Andrew T; Chen, Suzan
2013-03-01
The SERPINE1 -675 4G/5G promoter region insertion/deletion polymorphism (rs1799889) has been implicated in the pathogenesis of pre-eclampsia (PE), but the genetic association has been inconsistently replicated. To derive a more precise estimate of the association, a systematic review and meta-analysis was conducted. This study conformed to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed (MEDLINE), Scopus and HuGE Literature Finder literature databases were systematically searched for relevant studies. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for the allelic comparison (4G versus 5G) and genotypic comparisons following the co-dominant (4G/4G versus 5G/5G and 4G/5G versus 5G/5G), dominant (4G/4G+4G/5G versus 5G/5G) and recessive (4G/4G versus 4G/5G+5G/5G) genetic models. Between-study heterogeneity was quantified by I(2) statistics and publication bias was appraised with funnel plots. Sensitivity analysis was conducted to evaluate the robustness of meta-analysis findings. Meta-analysis of 11 studies involving 1297 PE cases and 1791 controls found a significant association between the SERPINE1 -675 4G/5G polymorphism and PE for the recessive genetic model (OR = 1.36, 95% CI: 1.13-1.64, P = 0.001), a robust finding according to sensitivity analysis. A low level of between-study heterogeneity was detected (I(2) = 20%) in this comparison, which may be explained by ethnic differences. Funnel plot inspection did not reveal evidence of publication bias. In conclusion, this study provides a comprehensive examination of the available literature on the association between SERPINE1 -675 4G/5G and PE. Meta-analysis results support this polymorphism as a likely susceptibility variant for PE.
Weiser, Keith C.; Liu, Bin; Hansen, Gwenn M.; Skapura, Darlene; Hentges, Kathryn E.; Yarlagadda, Sujatha; Morse III, Herbert C.
2007-01-01
AKXD recombinant inbred (RI) strains develop a variety of leukemias and lymphomas due to somatically acquired insertions of retroviral DNA into the genome of hematopoetic cells that can mutate cellular proto-oncogenes and tumor suppressor genes. We generated a new set of tumors from nine AKXD RI strains selected for their propensity to develop B-cell tumors, the most common type of human hematopoietic cancers. We employed a PCR technique called viral insertion site amplification (VISA) to rapidly isolate genomic sequence at the site of provirus insertion. Here we describe 550 VISA sequence tags (VSTs) that identify 74 common insertion sites (CISs), of which 21 have not been identified previously. Several suspected proto-oncogenes and tumor suppressor genes lie near CISs, providing supportive evidence for their roles in cancer. Furthermore, numerous previously uncharacterized genes lie near CISs, providing a pool of candidate disease genes for future research. Pathway analysis of candidate genes identified several signaling pathways as common and powerful routes to blood cancer, including Notch, E-protein, NFκB, and Ras signaling. Misregulation of several Notch signaling genes was confirmed by quantitative RT-PCR. Our data suggest that analyses of insertional mutagenesis on a single genetic background are biased toward the identification of cooperating mutations. This tumor collection represents the most comprehensive study of the genetics of B-cell leukemia and lymphoma development in mice. We have deposited the VST sequences, CISs in a genome viewer, histopathology, and molecular tumor typing data in a public web database called VISION (Viral Insertion Sites Identifying Oncogenes), which is located at http://www.mouse-genome.bcm.tmc.edu/vision. PMID:17926094
Weiser, Keith C; Liu, Bin; Hansen, Gwenn M; Skapura, Darlene; Hentges, Kathryn E; Yarlagadda, Sujatha; Morse Iii, Herbert C; Justice, Monica J
2007-10-01
AKXD recombinant inbred (RI) strains develop a variety of leukemias and lymphomas due to somatically acquired insertions of retroviral DNA into the genome of hematopoetic cells that can mutate cellular proto-oncogenes and tumor suppressor genes. We generated a new set of tumors from nine AKXD RI strains selected for their propensity to develop B-cell tumors, the most common type of human hematopoietic cancers. We employed a PCR technique called viral insertion site amplification (VISA) to rapidly isolate genomic sequence at the site of provirus insertion. Here we describe 550 VISA sequence tags (VSTs) that identify 74 common insertion sites (CISs), of which 21 have not been identified previously. Several suspected proto-oncogenes and tumor suppressor genes lie near CISs, providing supportive evidence for their roles in cancer. Furthermore, numerous previously uncharacterized genes lie near CISs, providing a pool of candidate disease genes for future research. Pathway analysis of candidate genes identified several signaling pathways as common and powerful routes to blood cancer, including Notch, E-protein, NFkappaB, and Ras signaling. Misregulation of several Notch signaling genes was confirmed by quantitative RT-PCR. Our data suggest that analyses of insertional mutagenesis on a single genetic background are biased toward the identification of cooperating mutations. This tumor collection represents the most comprehensive study of the genetics of B-cell leukemia and lymphoma development in mice. We have deposited the VST sequences, CISs in a genome viewer, histopathology, and molecular tumor typing data in a public web database called VISION (Viral Insertion Sites Identifying Oncogenes), which is located at http://www.mouse-genome.bcm.tmc.edu/vision .
Zaballos, Matilde; Bastida, Emilia; Agustí, Salomé; Portas, Maite; Jiménez, Consuelo; López-Gil, Maite
2015-10-06
A new supraglottic device, the LMA-Supreme™, has recently become available for clinical use. Information on anaesthetic and co-adjuvant requirements for insertion of the LMA-Supreme™ is limited. The present study aimed to evaluate the optimal effect-site concentration of propofol in 50 % (EC50) of adults necessary for successful insertion of the LMA-Supreme™ and to examine remifentanil's effect on propofol requirements. Fifty-eight elective patients (aged 18-60 years; ASA (American Society Anaesthesiologists) physical status classification I and II) scheduled for day surgery were randomly assigned to one of two groups: propofol with saline or propofol with remifentanil. Anaesthesia was induced by target-controlled infusion according to predetermined effect-site concentrations of propofol and remifentanil (5 ng.mL(-1)). The EC50 was calculated using Dixon's up-and-down method. Ten minutes following drug administration, LMA-Supreme™ insertion was attempted without the use of muscle relaxant drugs. In the propofol + saline group, the EC50 of propofol required for LMA-Supreme™ insertion was 6.32 ± 0.67 μg.mL(-1) (95 % CI, 5.69-6.94 μg.mL(-1)). With the addition of remifentanil at an effect-site concentration of 5 ng.mL(-1), the EC50 of propofol required for LMA-Supreme™ insertion was 2.50 ± 0.80 μg.mL(-1) (95 % CI, 1.82-3.17 μg.mL(-1); p < 0.0001). The propofol requirement for smooth insertion of the LMA-Supreme™ was 60 % less when remifentanil (5 ng.mL(-1)) was co-administered. Identified as NCT01974648 at www.clinicaltrials.gov .
Family of pH-Low-Insertion-Peptides (pHLIPs)
NASA Astrophysics Data System (ADS)
Weerakkody, Dhammika; Moshnikova, Anna; Moshnikova, Valentina; Thakur, Mak; Rossi, Bethany; Engelman, Donald; Andreev, Oleg; Reshetnyak, Yana
2012-02-01
pHLIP (pH (Low) Insertion Peptide) is a novel delivery system for targeting of acidic diseased tissue such as solid tumors, sites of inflammation, arthritis and other pathological states. The molecular mechanism of pHLIP action is based on pH-dependent insertion and folding of pHLIP in membrane. We performed sequence variation and investigated 16 pHLIP variants with main goals of understanding the main principles of peptide-lipid interactions and tune delivery capability of pHLIP. The biophysical studies including thermodynamics and kinetics of the peptides interaction with a lipid bilayer of liposomes and cellular membranes were carried out. We found that peptides association to membrane at neutral and low pH could be modulated by 3-4 times. The apparent pK of transition from surface bound to membrane-inserted state could be tuned from 6.5 to 4.5. The rate of peptide's insertion across a bilayer could be enhanced 100 times compared to parent pHLIP. As a result, blood clearance and tumor targeting were modulated in a significant degree. The work is supported by NIH grants CA133890 to OAA, DME, YRK.
Rajkumar, Sankaranarayanan; Vasavada, Abhay R.; Praveen, Mamidipudi R.; Ananthan, Rajendran; Reddy, Geereddy B.; Tripathi, Harsha; Ganatra, Darshini A.; Arora, Anshul I.; Patel, Alpesh R.
2013-01-01
Purpose. To explore different molecular factors impairing the activities of superoxide dismutase (SOD) isoforms in senile cataractous lenses. Methods. Enzyme activity of SOD isoforms, levels of their corresponding cofactors copper (Cu), manganese (Mn), zinc (Zn), and expression of mRNA transcripts and proteins were determined in the lenses of human subjects with and without cataract. DNA from lens epithelium (LE) and peripheral blood was isolated. Polymerase chain reaction–single strand conformation polymorphism (PCR-SSCP) followed by sequencing was carried out to screen somatic mutations. The impact of intronic insertion/deletion (INDEL) variations on the splicing process and on the resultant transcript was evaluated. Genotyping of IVS4+42delG polymorphism of SOD1 gene was done by PCR–restriction fragment length polymorphism (RFLP). Results. A significant decrease in Cu/Zn- and Mn-SOD activity (P < 0.001) and in Cu/Zn-SOD transcript (P < 0.001) and its protein (P < 0.05) were found in cataractous lenses. No significant change in the level of copper (P = 0.36) and an increase in the level of manganese (P = 0.01) and zinc (P = 0.02) were observed in cataractous lenses. A significant positive correlation between the level of Cu/Zn-SOD activity and the levels of Cu (P = 0.003) and Zn (P = 0.005) was found in the cataractous lenses. DNA sequencing revealed three intronic INDEL variations in exon4 of SOD1 gene. Splice-junction analysis showed the potential of IVS4+42delG in creating a new cryptic acceptor site. If it is involved in alternate splicing, it could result in generation of SOD1 mRNA transcripts lacking exon4 region. Transcript analysis revealed the presence of complete SOD1 mRNA transcripts. Genotyping revealed the presence of IVS4+42delG polymorphism in all subjects. Conclusions. The decrease in the activity of SOD1 isoform in cataractous lenses was associated with the decreased level of mRNA transcripts and their protein expression and was not associated with either modulation in the level of enzyme cofactors or with INDEL variations. PMID:23970468
Kawabe, Yoshinori; Shimomura, Takuya; Huang, Shuohao; Imanishi, Suguru; Ito, Akira; Kamihira, Masamichi
2016-07-01
Retroviral vectors have served as efficient gene delivery tools in various biotechnology fields. However, viral DNA is randomly inserted into the genome, which can cause problems, such as insertional mutagenesis and gene silencing. Previously, we reported a site-specific gene integration system, in which a transgene is integrated into a predetermined chromosomal locus of Chinese hamster ovary (CHO) cells using integrase-defective retroviral vectors (IDRVs) and Cre recombinase. In this system, a Cre expression plasmid is transfected into founder cells before retroviral transduction. In practical applications of site-specific gene modification such as for hard-to-transfect cells or for in vivo gene delivery, both the transgene and the Cre protein into retroviral virions should be encapsulate. Here, we generated novel hybrid IDRVs in which viral genome and enzymatically active Cre can be delivered (Cre-IDRVs). Cre-IDRVs encoding marker genes, neomycin resistance and enhanced green fluorescent protein (EGFP), flanked by wild-type and mutated loxP sites were produced using an expression plasmid for a chimeric protein of Cre and retroviral gag-pol. After analyzing the incorporation of the Cre protein into retroviral virions by Western blotting, the Cre-IDRV was infected into founder CHO cells, in which marker genes (hygromycin resistance and red fluorescent protein) flanked with corresponding loxP sites are introduced into the genome. G418-resistant colonies expressing GFP appeared and the site-specific integration of the transgene into the expected chromosomal site was confirmed by PCR and sequencing of amplicons. Moreover, when Cre-IDRV carried a gene expression unit for a recombinant antibody, the recombinant cells in which the antibody expression cassette was integrated in a site-specific manner were generated and the cells produced the recombinant antibody. This method may provide a promising tool to perform site-specific gene modification according to Cre-based cell engineering. Biotechnol. Bioeng. 2016;113: 1600-1610. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Fukushima, Yaeko
2017-01-01
Purpose The goal of the study was to survey ankle joint disorder in male senior high school and college student basketball players based on the results of an ultrasonographic medical check-up of the ankle joint. Materials and Methods The subjects were 17 senior high school student and 19 college student basketball players. Ultrasonography, evaluation of ATFL injury, and examination of the talocrural joint region were performed. The subjects were grouped based on the presence or absence of old ATFL injury, and subjects with ATFL injury were classified by the injured region: fibular insertion site, parenchyma, and talar insertion site. The talocrural joint region was evaluated based on the areas of the lateral margin, central region, and medial margin, and sites with an irregular bone contour and osteophyte were counted individually. The questionnaire asked about the patients’ history of ankle injuries. Results A questionnaire survey revealed that 70–79% of all subjects had experienced a sprain at least once and 21–29% had frequently sprained the left or right foot 10 or more times in the past. On ultrasonography, there was no significant difference in ligament injury or injured site between the senior high school and college students, but the number of osteochondral findings in the talocrural joint region was significantly higher in the college students. In addition, the number of injured sites significantly increased in those with 10 or more years of playing experience. Conclusion These results suggest that disorder of the talocrural joint region progresses with an increase in years of experience in student basketball players who do not take specific preventive measures against this injury. PMID:28603784
Fava, Cristiano; Montagnana, Martina; Danese, Elisa; Sjögren, Marketa; Almgren, Peter; Engström, Gunnar; Hedblad, Bo; Guidi, Gian Cesare; Minuz, Pietro; Melander, Olle
2012-07-19
Renalase (gene name RNLS), a recently discovered enzyme with monoamine oxidase activity, is implicated in the degradation of catecholamines. Recent studies delineate a possible role of this enzyme in blood pressure (BP) maintenance and cardiac protection and two single nucleotide polymorphisms, RNLS rs2576178 A > G and rs2296545 C > G have been associated with hypertension. The latter SNP leads to a non synonymous Asp to Glu substitution deleting a flavin adenine dinucleotide (FAD) binding site with possible impaired functionality. We tested the hypothesis that these polymorphisms could affect BP levels, hypertension prevalence, and risk of incident cardiovascular events in middle-aged Swedes. The polymorphisms were genotyped in 5696 participants of the population-based Cardiovascular Cohort of the "Malmö Diet and Cancer" (MDC-CC). The incidence of cardiovascular events (coronary events [n = 408], strokes [n = 330], heart failure [n = 190] and atrial fibrillation/flutter [n = 406]) was monitored for an average of approximately 15 years of follow-up. Both before and after adjustment for sex, age and BMI the polymorphisms did not show any effect on BP level and hypertension prevalence. Before and after adjustment for major cardiovascular risk factors, the hazard ratio for cardiac and cerebrovascular events was not significantly different in carriers of different genotypes. A significant interaction was found between the rs2296545 C > G and age with respect to BP/hypertension. Our data do not support a major role for these RNLS polymorphisms in determining BP level and incident events at population level. The positive interaction with age suggest that the effect of the rs2296545 C > G polymorphism, if any, could vary between different ages.
Hong, Y. P.; Hipkins, V. D.; Strauss, S. H.
1993-01-01
The amount, distribution and mutational nature of chloroplast DNA polymorphisms were studied via analysis of restriction fragment length polymorphisms in three closely related species of conifers, the California closed-cone pines-knobcone pine: Pinus attenuata Lemm.; bishop pine: Pinus muricata D. Don; and Monterey pine: Pinus radiata D. Don. Genomic DNA from 384 trees representing 19 populations were digested with 9-20 restriction enzymes and probed with cloned cpDNA fragments from Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] that comprise 82% of the chloroplast genome. Up to 313 restriction sites were surveyed, and 25 of these were observed to be polymorphic among or within species. Differences among species accounted for the majority of genetic (haplotypic) diversity observed [G(st) = 84(+/-13)%]; nucleotide diversity among species was estimated to be 0.3(+/-0.1)%. Knobcone pine and Monterey pine displayed almost no genetic variation within or among populations. Bishop pine also showed little variability within populations, but did display strong population differences [G(st) = 87(+/-8)%] that were a result of three distinct geographic groups. Mean nucleotide diversity within populations was 0.003(+/-0.002)%; intrapopulation polymorphisms were found in only five populations. This pattern of genetic variation contrasts strongly with findings from study of nuclear genes (allozymes) in the group, where most genetic diversity resides within populations rather than among populations or species. Regions of the genome subject to frequent length mutations were identified; estimates of subdivision based on length variant frequencies in one region differed strikingly from those based on site mutations or allozymes. Two trees were identified with a major chloroplast DNA inversion that closely resembled one documented between Pinus and Pseudotsuga. PMID:7905846
Polymorphism analysis of prion protein gene in 11 Pakistani goat breeds
Hassan, Mohammad Farooque; Khan, Sher Hayat; Babar, Masroor Ellahi; Yang, Lifeng; Ali, Tariq; Khan, Jamal Muhammad; Shah, Syed Zahid Ali; Zhou, Xiangmei; Hussain, Tanveer; Zhu, Ting; Hussain, Tariq; Zhao, Deming
2016-01-01
ABSTRACT The association between caprine PrP gene polymorphisms and its susceptibility to scrapie has been investigated in current years. As the ORF of the PrP gene is extremely erratic in different breeds of goats, we studied the PrP gene polymorphisms in 80 goats which belong to 11 Pakistani indigenous goat breeds from all provinces of Pakistan. A total of 6 distinct polymorphic sites (one novel) with amino acid substitutions were identified in the PrP gene which includes 126 (A -> G), 304 (G -> T), 379 (A -> G), 414 (C -> T), 428 (A -> G) and 718 (C -> T). The locus c.428 was found highly polymorphic in all breeds as compare to other loci. On the basis of these PrP variants NJ phylogenetic tree was constructed through MEGA6.1 which showed that all goat breeds along with domestic sheep and Mauflon sheep appeared as in one clade and sharing its most recent common ancestors (MRCA) with deer species while Protein analysis has shown that these polymorphisms can lead to varied primary, secondary and tertiary structure of protein. Based on these polymorphic variants, genetic distance, multidimensional scaling plot and principal component analyses revealed the clear picture regarding greater number of substitutions in cattle PrP regions as compared to the small ruminant species. In particular these findings may pinpoint the fundamental control over the scrapie in Capra hircus on genetic basis. PMID:27388702
Bonatelli, Isabel A S; Carstens, Bryan C; Moraes, Evandro M
2015-01-01
Microsatellite markers (also known as SSRs, Simple Sequence Repeats) are widely used in plant science and are among the most informative molecular markers for population genetic investigations, but the development of such markers presents substantial challenges. In this report, we discuss how next generation sequencing can replace the cloning, Sanger sequencing, identification of polymorphic loci, and testing cross-amplification that were previously required to develop microsatellites. We report the development of a large set of microsatellite markers for five species of the Neotropical cactus genus Pilosocereus using a restriction-site-associated DNA sequencing (RAD-seq) on a Roche 454 platform. We identified an average of 165 microsatellites per individual, with the absolute numbers across individuals proportional to the sequence reads obtained per individual. Frequency distribution of the repeat units was similar in the five species, with shorter motifs such as di- and trinucleotide being the most abundant repeats. In addition, we provide 72 microsatellites that could be potentially amplified in the sampled species and 22 polymorphic microsatellites validated in two populations of the species Pilosocereus machrisii. Although low coverage sequencing among individuals was observed for most of the loci, which we suggest to be more related to the nature of the microsatellite markers and the possible bias inserted by the restriction enzymes than to the genome size, our work demonstrates that an NGS approach is an efficient method to isolate multispecies microsatellites even in non-model organisms.
Bonatelli, Isabel A. S.; Carstens, Bryan C.; Moraes, Evandro M.
2015-01-01
Microsatellite markers (also known as SSRs, Simple Sequence Repeats) are widely used in plant science and are among the most informative molecular markers for population genetic investigations, but the development of such markers presents substantial challenges. In this report, we discuss how next generation sequencing can replace the cloning, Sanger sequencing, identification of polymorphic loci, and testing cross-amplification that were previously required to develop microsatellites. We report the development of a large set of microsatellite markers for five species of the Neotropical cactus genus Pilosocereus using a restriction-site-associated DNA sequencing (RAD-seq) on a Roche 454 platform. We identified an average of 165 microsatellites per individual, with the absolute numbers across individuals proportional to the sequence reads obtained per individual. Frequency distribution of the repeat units was similar in the five species, with shorter motifs such as di- and trinucleotide being the most abundant repeats. In addition, we provide 72 microsatellites that could be potentially amplified in the sampled species and 22 polymorphic microsatellites validated in two populations of the species Pilosocereus machrisii. Although low coverage sequencing among individuals was observed for most of the loci, which we suggest to be more related to the nature of the microsatellite markers and the possible bias inserted by the restriction enzymes than to the genome size, our work demonstrates that an NGS approach is an efficient method to isolate multispecies microsatellites even in non-model organisms. PMID:26561396
Dissanayake, Vajira H W; Sirisena, Nirmala D; Weerasekera, Lakshini Y; Gammulla, Chumithri G; Seneviratne, Harshalal R; Jayasekara, Rohan W
2012-09-01
Genetic thrombophilias are known to contribute to adverse pregnancy outcomes. Studies in Western populations show that 5, 10-methylenetetrahydrofolate reductase (MTHFR) 677C>T and Factor V (F5) 1691G>A (Leiden) polymorphisms are commonly associated with pre-eclampsia and recurrent spontaneous pregnancy loss. The objective of this study was to investigate the association of MTHFR 677C>T (rs1801133); 1298A>C (rs1801131) and F5 1691G>A (rs6025); 4070A>G (rs1800595) polymorphisms with pre-eclampsia and recurrent pregnancy loss among Sinhalese women in Sri Lanka. Genotype and allele frequencies at each polymorphic site in the MTHFR and F5 genes and the haplotypes defined by them were determined in 175 Sinhalese women with pre-eclampsia, 171 normotensive controls, 200 Sinhalese women with two or more recurrent pregnancy losses and 200 controls with two or more living children and no pregnancy losses. Genotyping was done by polymerase chain reaction/restriction fragment length polymorphism. Odds ratios and χ(2) -testing were performed to compare genotype/haplotype frequencies at each polymorphic site for both cases and controls. The genotype frequencies at each polymorphic site in the MTHFR 677C>T; 1298A>C; F5 1691G>A and 4070A>G genes and the haplotypes defined by them were not significantly associated with either pre-eclampsia or recurrent pregnancy loss. There was no significant association of genetic thrombophilia with either early or late pregnancy losses. The MTHFR and F5 polymorphisms and the haplotypes defined by them were not significantly associated with either pre-eclampsia or recurrent pregnancy loss in this group of Sinhalese women. © 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.
Chromosome-based genetic complementation system for Xylella fastidiosa.
Matsumoto, Ayumi; Young, Glenn M; Igo, Michele M
2009-03-01
Xylella fastidiosa is a xylem-limited, gram-negative bacterium that causes Pierce's disease of grapevine. Here, we describe the construction of four vectors that facilitate the insertion of genes into a neutral site (NS1) in the X. fastidiosa chromosome. These vectors carry a colE1-like (pMB1) replicon and DNA sequences from NS1 flanking a multiple-cloning site and a resistance marker for one of the following antibiotics: chloramphenicol, erythromycin, gentamicin, or kanamycin. In X. fastidiosa, vectors with colE1-like (pMB1) replicons have been found to result primarily in the recovery of double recombinants rather than single recombinants. Thus, the ease of obtaining double recombinants and the stability of the resulting insertions at NS1 in the absence of selective pressure are the major advantages of this system. Based on in vitro and in planta characterizations, strains carrying insertions within NS1 are indistinguishable from wild-type X. fastidiosa in terms of growth rate, biofilm formation, and pathogenicity. To illustrate the usefulness of this system for complementation analysis, we constructed a strain carrying a mutation in the X. fastidiosa cpeB gene, which is predicted to encode a catalase/peroxidase, and showed that the sensitivity of this mutant to hydrogen peroxide could be overcome by the introduction of a wild-type copy of cpeB at NS1. Thus, this chromosome-based complementation system provides a valuable genetic tool for investigating the role of specific genes in X. fastidiosa cell physiology and virulence.
Praline, Julien; Blasco, Hélène; Vourc'h, Patrick; Rat, Valérian; Gendrot, Chantal; Camu, William; Andres, Christian R
2012-06-15
Our objective was to investigate whether the C282Y (p.Cys 282 Tyr) and H63D (p. His 63 Asp) HFE polymorphisms were associated with sporadic amyotrophic lateral sclerosis (SALS) in the French population. We searched for a relation of HFE polymorphisms with the clinical characteristics of the disease. The HFE polymorphisms were studied in 824 patients with SALS and 583 controls. We compared the frequency of the polymorphisms between SALS and controls groups by univariate and multivariate statistics, taking into account gender, site, age-at-onset and survival. We did not observe significant difference in the frequency of H63D polymorphism between SALS and control group. We observed a significant difference for C282Y between patients and controls with a low frequency of the Y allele in patients (3.2%) compared to our control group (5.9%). Disease duration, distribution of gender, site-of-onset, age-at-onset did not differ between groups taking into account genotypes of each polymorphism. Our results in this large cohort of ALS patients indicate that H63D polymorphism is not associated with SALS in the French population. This conclusion does not exclude a weak effect of the HFE gene polymorphisms in certain ALS populations, or an effect of other rare HFE gene variants. Copyright © 2012 Elsevier B.V. All rights reserved.
2014-01-01
Background Small insertion and deletion polymorphisms (Indels) are the second most common mutations in the human genome, after Single Nucleotide Polymorphisms (SNPs). Recent studies have shown that they have significant influence on genetic variation by altering human traits and can cause multiple human diseases. In particular, many Indels that occur in protein coding regions are known to impact the structure or function of the protein. A major challenge is to predict the effects of these Indels and to distinguish between deleterious and neutral variants. When an Indel occurs within a coding region, it can be either frameshifting (FS) or non-frameshifting (NFS). FS-Indels either modify the complete C-terminal region of the protein or result in premature termination of translation. NFS-Indels insert/delete multiples of three nucleotides leading to the insertion/deletion of one or more amino acids. Results In order to study the relationships between NFS-Indels and Mendelian diseases, we characterized NFS-Indels according to numerous structural, functional and evolutionary parameters. We then used these parameters to identify specific characteristics of disease-causing and neutral NFS-Indels. Finally, we developed a new machine learning approach, KD4i, that can be used to predict the phenotypic effects of NFS-Indels. Conclusions We demonstrate in a large-scale evaluation that the accuracy of KD4i is comparable to existing state-of-the-art methods. However, a major advantage of our approach is that we also provide the reasons for the predictions, in the form of a set of rules. The rules are interpretable by non-expert humans and they thus represent new knowledge about the relationships between the genotype and phenotypes of NFS-Indels and the causative molecular perturbations that result in the disease. PMID:24742296
Weitemier, Kevin; Straub, Shannon C K; Fishbein, Mark; Liston, Aaron
2015-01-01
Despite knowledge that concerted evolution of high-copy loci is often imperfect, studies that investigate the extent of intragenomic polymorphisms and comparisons across a large number of species are rarely made. We present a bioinformatic pipeline for characterizing polymorphisms within an individual among copies of a high-copy locus. Results are presented for nuclear ribosomal DNA (nrDNA) across the milkweed genus, Asclepias. The 18S-26S portion of the nrDNA cistron of Asclepias syriaca served as a reference for assembly of the region from 124 samples representing 90 species of Asclepias. Reads were mapped back to each individual's consensus and at each position reads differing from the consensus were tallied using a custom perl script. Low frequency polymorphisms existed in all individuals (mean = 5.8%). Most nrDNA positions (91%) were polymorphic in at least one individual, with polymorphic sites being less frequent in subunit regions and loops. Highly polymorphic sites existed in each individual, with highest abundance in the "noncoding" ITS regions. Phylogenetic signal was present in the distribution of intragenomic polymorphisms across the genus. Intragenomic polymorphisms in nrDNA are common in Asclepias, being found at higher frequency than any other study to date. The high and variable frequency of polymorphisms across species highlights concerns that phylogenetic applications of nrDNA may be error-prone. The new analytical approach provided here is applicable to other taxa and other high-copy regions characterized by low coverage genome sequencing (genome skimming).
Transdiaphragmatic Approach to Attenuate Porto-Azygos Shunts Inserting in the Thorax.
Or, Matan; Kitshoff, Adriaan; Devriendt, Nausikaa; De Ridder, Marianne; Quist-Rybachuk, Galena; de Rooster, Hilde
2016-11-01
To describe the surgical technique and document the application of a transdiaphragmatic approach to attenuate porto-azygos shunts inserting in the thoracic section of the azygos vein. Cadaveric study and prospective case series. Canine cadavers (n=6) and client-owned dogs with porto-azygos shunts inserting in the thoracic section of the azygos vein (n=9). In the cadavers, the azygos vein was filled with aqueous latex. Landmarks were established for creating a safe transdiaphragmatic approach to the caudal intrathoracic portion of the azygos vein. In the clinical cases, porto-azygos communication was diagnosed by trans-splenic portal scintigraphy. All shunts were attenuated close to their insertion site via ventral midline celiotomy and a transdiaphragmatic approach to the shunt. Perioperative complications were recorded. A 3-5 cm incision, 0.5-1 cm ventral and lateral to the level of the aortic hiatus, was made in the pars lumbalis part of the diaphragm. Stay sutures at both sides of the diaphragmatic incision were placed to open up the incision and a retractor was used to push the esophagus away from the aorta. Intrathoracic insertion of the shunt was confirmed intraoperative. Exposure of the shunt insertion site at the azygos vein was excellent in all clinical cases. No intraoperative or postoperative complications were encountered. If thoracic attenuation of a porto-azygos shunt is considered, a transdiaphragmatic approach exposes the insertion site for shunt attenuation. This approach is straightforward, without unnecessary abdominal organ manipulation, and since attenuates at the insertion, avoids missing additional contributing branches. © Copyright 2016 by The American College of Veterinary Surgeons.
Kassis, J. A.
1994-01-01
We have previously shown that a 2-kb fragment of engrailed DNA can suppress expression of a linked marker gene, white, in the P element vector CaSpeR. This suppression is dependent on the presence of two copies of engrailed DNA-containing P elements (P[en]) in proximity in the Drosophila genome (either in cis or in trans). In this study, the 2-kb fragment was dissected and found to contain three fragments of DNA which could mediate white suppression [called ``pairing-sensitive sites'' (PS)]. A PS site was also identified in regulatory DNA from the Drosophila escargot gene. The eye colors of six different P[en] insertions in the escargot gene suggest an interaction between P[en]-encoded and genome-encoded PS sites. I hypothesize that white gene expression from P[en] is repressed by the formation of a protein complex which is initiated at the engrailed PS sites and also requires interactions with flanking genomic DNA. Genes were sought which influence the function of PS sites. Mutations in some Polycomb and trithorax group genes were found to affect the eye color from some P[en] insertion sites. However, different mutations affected expression from different P[en] insertion sites and no one mutation was found to affect expression from all P[en] insertion sites examined. These results suggest that white expression from P[en] is not directly regulated by members of the Polycomb and trithorax group genes, but in some cases can be influenced by them. I propose that engrailed PS sites normally act to promote interactions between distantly located engrailed regulatory sites and the engrailed promoter. PMID:8005412
A High-Throughput Arabidopsis Reverse Genetics System
Sessions, Allen; Burke, Ellen; Presting, Gernot; Aux, George; McElver, John; Patton, David; Dietrich, Bob; Ho, Patrick; Bacwaden, Johana; Ko, Cynthia; Clarke, Joseph D.; Cotton, David; Bullis, David; Snell, Jennifer; Miguel, Trini; Hutchison, Don; Kimmerly, Bill; Mitzel, Theresa; Katagiri, Fumiaki; Glazebrook, Jane; Law, Marc; Goff, Stephen A.
2002-01-01
A collection of Arabidopsis lines with T-DNA insertions in known sites was generated to increase the efficiency of functional genomics. A high-throughput modified thermal asymetric interlaced (TAIL)-PCR protocol was developed and used to amplify DNA fragments flanking the T-DNA left borders from ∼100,000 transformed lines. A total of 85,108 TAIL-PCR products from 52,964 T-DNA lines were sequenced and compared with the Arabidopsis genome to determine the positions of T-DNAs in each line. Predicted T-DNA insertion sites, when mapped, showed a bias against predicted coding sequences. Predicted insertion mutations in genes of interest can be identified using Arabidopsis Gene Index name searches or by BLAST (Basic Local Alignment Search Tool) search. Insertions can be confirmed by simple PCR assays on individual lines. Predicted insertions were confirmed in 257 of 340 lines tested (76%). This resource has been named SAIL (Syngenta Arabidopsis Insertion Library) and is available to the scientific community at www.tmri.org. PMID:12468722
Ramanathan, Gnanasambandan; Ghosh, Santu; Elumalai, Ramprasad; Periyasamy, Soundararajan; Lakkakula, Bhaskar V K S
2016-06-01
Autosomal dominant polycystic kidney disease (ADPKD) is an inherited systemic disorder, characterized by the fluid filled cysts in the kidneys leading to end stage renal failure in later years of life. Hypertension is one of the major factors independently contributing to the chronic kidney disease (CKD) progression. The renin-angiotensin aldosterone system (RAAS) genes have been extensively studied as hypertension candidate genes. The aim of the present study was to investigate the role of angiotensin converting enzyme tagging - single nucleotide polymorphisms (ACE tag-SNPs) in progression of CKD in patients with ADPKD. m0 ethods: In the present study six ACE tagSNPs (angiotensin converting enzyme tag single nucleotide polymorphisms) and insertion/deletion (I/D) in 102 ADPKD patients and 106 control subjects were investigated. The tagSNPs were genotyped using FRET-based KASPar method and ACE ID by polymerase chain reaction (PCR) and electrophoresis. Genotypes and haplotypes were compared between ADPKD patients and controls. Univariate and multivariate logistic regression analyses were performed to assess the effect of genotypes and hypertension on CKD advancement. Mantel-Haenszel (M-H) stratified analysis was performed to study the relationship between different CKD stages and hypertension and their interaction. All loci were polymorphic and except rs4293 SNP the remaining loci followed Hardy-Weinberg equilibrium. Distribution of ACE genotypes and haplotypes in controls and ADPKD patients was not significant. A significant linkage disequilibrium (LD) was observed between SNPs forming two LD blocks. The univariate analysis revealed that the age, hypertension, family history of diabetes and ACE rs4362 contributed to the advancement of CKD. The results suggest that the ACE genotypes are effect modifiers of the relationship between hypertension and CKD advancement among the ADPKD patients.
ErbB polymorphisms: insights and implications for response to targeted cancer therapeutics.
Alaoui-Jamali, Moulay A; Morand, Grégoire B; da Silva, Sabrina Daniela
2015-01-01
Advances in high-throughput genomic-scanning have expanded the repertory of genetic variations in DNA sequences encoding ErbB tyrosine kinase receptors in humans, including single nucleotide polymorphisms (SNPs), polymorphic repetitive elements, microsatellite variations, small-scale insertions and deletions. The ErbB family members: EGFR, ErbB2, ErbB3, and ErbB4 receptors are established as drivers of many aspects of tumor initiation and progression to metastasis. This knowledge has provided rationales for the development of an arsenal of anti-ErbB therapeutics, ranging from small molecule kinase inhibitors to monoclonal antibodies. Anti-ErbB agents are becoming the cornerstone therapeutics for the management of cancers that overexpress hyperactive variants of ErbB receptors, in particular ErbB2-positive breast cancer and non-small cell lung carcinomas. However, their clinical benefit has been limited to a subset of patients due to a wide heterogeneity in drug response despite the expression of the ErbB targets, attributed to intrinsic (primary) and to acquired (secondary) resistance. Somatic mutations in ErbB tyrosine kinase domains have been extensively investigated in preclinical and clinical setting as determinants for either high sensitivity or resistance to anti-ErbB therapeutics. In contrast, only scant information is available on the impact of SNPs, which are widespread in genes encoding ErbB receptors, on receptor structure and activity, and their predictive values for drug susceptibility. This review aims to briefly update polymorphic variations in genes encoding ErbB receptors based on recent advances in deep sequencing technologies, and to address challenging issues for a better understanding of the functional impact of single versus combined SNPs in ErbB genes to receptor topology, receptor-drug interaction, and drug susceptibility. The potential of exploiting SNPs in the era of stratified targeted therapeutics is discussed.
Pedersen, N C; Dhanota, J K; Liu, H
2016-10-15
Specific polymorphisms in the endoplasmic reticulum amino peptidase genes ERAP1 and ERAP2, when present with certain MHC class receptor types, have been associated with increased risk for specific cancers, infectious diseases and autoimmune disorders in humans. This increased risk has been linked to distinct polymorphisms in both ERAPs and MHC class I receptors that affect the way cell-generated peptides are screened for antigenicity. The incidence of cancer, infectious disease and autoimmune disorders differ greatly among pure breeds of dogs as it does in humans and it is possible that this heightened susceptibility is also due to specific polymorphisms in ERAP1 and ERAP2. In order to determine if such polymorphisms exist, the ERAP1 and ERAP2 genes of 10 dogs of nine diverse breeds were sequenced and SNPs causing synonymous or non-synonymous amino acid changes, deletions or insertions were identified. Eight ERAP1 and 10 ERAP2 SNPs were used to create a Sequenom MassARRAY iPLEX based test panel which defined 24 ERAP1, 36 ERAP2 and 128 ERAP1/2 haplotypes. The prevalence of these haplotypes was then measured among dog, wolf, coyote, jackal and red fox populations. Some haplotypes were species specific, while others were shared across species, especially between dog, wolf, coyote and jackal. The prevalence of these haplotypes was then compared among various canid populations, and in particular between various populations of random- and pure-bred dogs. Human-directed positive selection has led to loss of ERAP diversity and segregation of certain haplotypes among various dog breeds. A phylogenetic tree generated from 45 of the most common ERAP1/2 haplotypes demonstrated three distinct clades, all of which were rooted with haplotypes either shared among species or specific to contemporary dogs, coyote and wolf. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Zaffanello, Marco; Tardivo, Stefano; Cataldi, Luigi; Fanos, Vassilios; Biban, Paolo; Malerba, Giovanni
2011-07-01
Identifying patients who may develop renal scarring after urinary tract infections (UTI) remains challenging, as clinical determinants explain only a portion of individual risk. An additional factor that likely affects risk is individual genetic variability. We searched for peer-reviewed articles from 1980 to December 2009 in electronic databases that reported results showing an association between gene polymorphims and renal scaring after UTI. Two independent researchers screened articles using predetermined criteria. Studies were assessed for methodological quality using an aggregate scoring system. The 18 studies ultimately included in the review had investigated 16 polymorphisms in nine genes in association with renal scarring formation after UTI. Based on the predetermined criteria for assessing the quality of the studies, 12 studies (67%) were identified as being of poor quality design. A meta-analysis of cumulative studies showed on association between renal scarring formation after UTI and the angiotensin converting enzyme insertion/deletion polymorphism [ACE I/D; recessive model for D allele; odds ratio (OR) 1.73, 95% confidence interval (CI) 1.09-2.74, P = 0.02] or transforming growth factor (TGF)-β1 c.-509 T > C polymorphism (dominant model for T allele; OR 2.24, 95% CI 1.34-3.76, P = 0.002). However, heterogeneity among studies was large, indicating a strong difference that cannot only be explained by differences in study design. The studies reviewed in this article support a modest involvement of the vasomotor and inflammatory genes in the development of renal scarring after UTIs. This review also shows that only few possible candidate genes have been investigated for an association with renal scarring, raising the hypothesis that some gene polymorphisms may exert their effects through an interaction with as yet uninvestigated factors that may be related to geographic and/or socio-economic differences.
Moloney, Claire; Griffin, Denis; Jones, Peter W; Bryan, Glenn J; McLean, Karen; Bradshaw, John E; Milbourne, Dan
2010-02-01
Quantitative resistance to Globodera pallida pathotype Pa2/3, originally derived from Solanum tuberosum ssp. andigena Commonwealth Potato Collection (CPC) accession 2802, is present in several potato cultivars and advanced breeding lines. One genetic component of this resistance, a large effect quantitative trait locus (QTL) on linkage group IV (which we have renamed GpaIV(adg)(s)) has previously been mapped in the tetraploid breeding line 12601ab1. In this study, we show that GpaIV(adg)(s) is also present in a breeding line called C1992/31 via genetic mapping in an F(1) population produced by crossing C1992/31 with the G. pallida susceptible cultivar Record. C1992/31 is relatively divergent from 12601ab1, confirming that GpaIV(adg)(s) is an ideal target for marker-assisted selection in currently available germplasm. To generate markers exhibiting diagnostic potential for GpaIV(adg)(s), three bacterial artificial chromosome clones were isolated from the QTL region, sequenced, and used to develop 15 primer sets generating single-copy amplicons, which were examined for polymorphisms exhibiting linkage to GpaIV(adg)(s) in C1992/31. Eight such polymorphisms were found. Subsequently, one insertion/deletion polymorphism, three single nucleotide polymorphisms and a specific allele of the microsatellite marker STM3016 were shown to exhibit diagnostic potential for the QTL in a panel of 37 potato genotypes, 12 with and 25 without accession CPC2082 in their pedigrees. STM3016 and one of the SNP polymorphisms, C237(119), were assayed in 178 potato genotypes, arising from crosses between C1992/31 and 16 G. pallida susceptible genotypes, undergoing selection in a commercial breeding programme. The results suggest that the diagnostic markers would most effectively be employed in MAS-based approaches to pyramid different resistance loci to develop cultivars exhibiting strong, durable resistance to G. pallida pathotype Pa2/3.
Phase variation and microevolution at homopolymeric tracts in Bordetella pertussis
Gogol, Emily B; Cummings, Craig A; Burns, Ryan C; Relman, David A
2007-01-01
Background Bordetella pertussis, the causative agent of whooping cough, is a highly clonal pathogen of the respiratory tract. Its lack of genetic diversity, relative to many bacterial pathogens, could limit its ability to adapt to a hostile and changing host environment. This limitation might be overcome by phase variation, as observed for other mucosal pathogens. One of the most common mechanisms of phase variation is reversible expansion or contraction of homopolymeric tracts (HPTs). Results The genomes of B. pertussis and the two closely related species, B. bronchiseptica and B. parapertussis, were screened for homopolymeric tracts longer than expected on the basis of chance, given their nucleotide compositions. Sixty-nine such HPTs were found in total among the three genomes, 74% of which were polymorphic among the three species. Nine HPTs were genotyped in a collection of 90 geographically and temporally diverse B. pertussis strains using the polymerase chain reaction/ligase detection reaction (PCR/LDR) assay. Six HPTs were polymorphic in this collection of B. pertussis strains. Of note, one of these polymorphic HPTs was found in the fimX promoter, where a single base insertion variant was present in seven strains, all of which were isolated prior to introduction of the pertussis vaccine. Transcript abundance of fimX was found to be 3.8-fold lower in strains carrying the longer allele. HPTs in three other genes, tcfA, bapC, and BP3651, varied widely in composition across the strain collection and displayed allelic polymorphism within single cultures. Conclusion Allelic polymorphism at homopolymeric tracts is common within the B. pertussis genome. Phase variability may be an important mechanism in B. pertussis for evasion of the immune system and adaptation to different niches in the human host. High sensitivity and specificity make the PCR/LDR assay a powerful tool for investigating allelic variation at HPTs. Using this method, allelic diversity and phase variation were demonstrated at several B. pertussis loci. PMID:17509142
Incremental triangulation by way of edge swapping and local optimization
NASA Technical Reports Server (NTRS)
Wiltberger, N. Lyn
1994-01-01
This document is intended to serve as an installation, usage, and basic theory guide for the two dimensional triangulation software 'HARLEY' written for the Silicon Graphics IRIS workstation. This code consists of an incremental triangulation algorithm based on point insertion and local edge swapping. Using this basic strategy, several types of triangulations can be produced depending on user selected options. For example, local edge swapping criteria can be chosen which minimizes the maximum interior angle (a MinMax triangulation) or which maximizes the minimum interior angle (a MaxMin or Delaunay triangulation). It should be noted that the MinMax triangulation is generally only locally optical (not globally optimal) in this measure. The MaxMin triangulation, however, is both locally and globally optical. In addition, Steiner triangulations can be constructed by inserting new sites at triangle circumcenters followed by edge swapping based on the MaxMin criteria. Incremental insertion of sites also provides flexibility in choosing cell refinement criteria. A dynamic heap structure has been implemented in the code so that once a refinement measure is specified (i.e., maximum aspect ratio or some measure of a solution gradient for the solution adaptive grid generation) the cell with the largest value of this measure is continually removed from the top of the heap and refined. The heap refinement strategy allows the user to specify either the number of cells desired or refine the mesh until all cell refinement measures satisfy a user specified tolerance level. Since the dynamic heap structure is constantly updated, the algorithm always refines the particular cell in the mesh with the largest refinement criteria value. The code allows the user to: triangulate a cloud of prespecified points (sites), triangulate a set of prespecified interior points constrained by prespecified boundary curve(s), Steiner triangulate the interior/exterior of prespecified boundary curve(s), refine existing triangulations based on solution error measures, and partition meshes based on the Cuthill-McKee, spectral, and coordinate bisection strategies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Villard, E.; Soubrier, F.; Tiret, L.
1996-06-01
Plasma angiotensin I-converting enzyme (ACE) levels are highly genetically determined. A previous segregation-linkage analysis suggested the existence of a functional mutation located within or close to the ACE locus, in almost complete linkage disequilibrium (LD) with the ACE insertion/deletion (I/D) polymorphism and accounting for half the ACE variance. In order to identify the functional variant at the molecular level, we compared ACE gene sequences between four subjects selected for having contrasted ACE levels and I/D genotypes. We identified 10 new polymorphisms, among which 8 were genotyped in 95 healthy nuclear families, in addition to the I/D polymorphism. These polymorphisms couldmore » be divided into two groups: five polymorphisms in the 5{prime} region and three in the coding sequence and the 3{prime} UTR. Within each group, polymorphisms were in nearly complete association, whereas polymorphisms from the two groups were in strong negative LD. After adjustment for the I/D polymorphism, all polymorphisms of the 5{prime} group remained significantly associated with ACE levels, which suggests the existence of two quantitative trait loci (QTL) acting additively on ACE levels. Segregation-linkage analyses including one or two ACE-linked QTLs in LD with two ACE markers were performed to test this hypothesis. The two QTLs and the two markers were assumed to be in complete LD. Results supported the existence of two ACE-linked QTLs, which would explain 38% and 49% of the ACE variance in parents and offspring, respectively. One of these QTLs might be the I/D polymorphism itself or the newly characterized 4656(CT){sub 2/3} polymorphism. The second QTL would have a frequency of {approximately}.20, which is incompatible with any of the yet-identified polymorphisms. More extensive sequencing and extended analyses in larger samples and in other populations will be necessary to characterize definitely the functional variants. 30 refs., 1 fig., 6 tabs.« less
Ntege, Edward H; Arisue, Nobuko; Ito, Daisuke; Hasegawa, Tomoyuki; Palacpac, Nirianne M Q; Egwang, Thomas G; Horii, Toshihiro; Takashima, Eizo; Tsuboi, Takafumi
2016-11-04
Genetic variability in Plasmodium falciparum malaria parasites hampers current malaria vaccine development efforts. Here, we hypothesize that to address the impact of genetic variability on vaccine efficacy in clinical trials, conserved antigen targets should be selected to achieve robust host immunity across multiple falciparum strains. Therefore, suitable vaccine antigens should be assessed for levels of polymorphism and genetic diversity. Using a total of one hundred and two clinical isolates from a region of high malaria transmission in Uganda, we analyzed extent of polymorphism and genetic diversity in four recently reported novel blood-stage malaria vaccine candidate proteins: Rh5 interacting protein (PfRipr), GPI anchored micronemal antigen (PfGAMA), rhoptry-associated leucine zipper-like protein 1 (PfRALP1) and Duffy binding-like merozoite surface protein 1 (PfMSPDBL1). In addition, utilizing the wheat germ cell-free system, we expressed recombinant proteins for the four candidates based on P. falciparum laboratory strain 3D7 sequences, immunized rabbits to obtain specific antibodies (Abs) and performed functional growth inhibition assay (GIA). The GIA activity of the raised Abs was demonstrated using both homologous 3D7 and heterologous FVO strains in vitro. Both pfripr and pfralp1 are less polymorphic but the latter is comparatively more diverse, with varied number of regions having insertions and deletions, asparagine and 6-mer repeats in the coding sequences. Pfgama and pfmspdbl1 are polymorphic and genetically diverse among the isolates with antibodies against the 3D7-based recombinant PfGAMA and PfMSPDBL1 inhibiting merozoite invasion only in the 3D7 but not FVO strain. Moreover, although Abs against the 3D7-based recombinant PfRipr and PfRALP1 proteins potently inhibited merozoite invasion of both 3D7 and FVO, the GIA activity of anti-PfRipr was much higher than that of anti-PfRALP1. Thus, PfRipr is regarded as a promising blood-stage vaccine candidate for next-generation vaccines against P. falciparum. Copyright © 2016 Elsevier Ltd. All rights reserved.
Enhancers Are Major Targets for Murine Leukemia Virus Vector Integration
De Ravin, Suk See; Su, Ling; Theobald, Narda; Choi, Uimook; Macpherson, Janet L.; Poidinger, Michael; Symonds, Geoff; Pond, Susan M.; Ferris, Andrea L.; Hughes, Stephen H.
2014-01-01
ABSTRACT Retroviral vectors have been used in successful gene therapies. However, in some patients, insertional mutagenesis led to leukemia or myelodysplasia. Both the strong promoter/enhancer elements in the long terminal repeats (LTRs) of murine leukemia virus (MLV)-based vectors and the vector-specific integration site preferences played an important role in these adverse clinical events. MLV integration is known to prefer regions in or near transcription start sites (TSS). Recently, BET family proteins were shown to be the major cellular proteins responsible for targeting MLV integration. Although MLV integration sites are significantly enriched at TSS, only a small fraction of the MLV integration sites (<15%) occur in this region. To resolve this apparent discrepancy, we created a high-resolution genome-wide integration map of more than one million integration sites from CD34+ hematopoietic stem cells transduced with a clinically relevant MLV-based vector. The integration sites form ∼60,000 tight clusters. These clusters comprise ∼1.9% of the genome. The vast majority (87%) of the integration sites are located within histone H3K4me1 islands, a hallmark of enhancers. The majority of these clusters also have H3K27ac histone modifications, which mark active enhancers. The enhancers of some oncogenes, including LMO2, are highly preferred targets for integration without in vivo selection. IMPORTANCE We show that active enhancer regions are the major targets for MLV integration; this means that MLV preferentially integrates in regions that are favorable for viral gene expression in a variety of cell types. The results provide insights for MLV integration target site selection and also explain the high risk of insertional mutagenesis that is associated with gene therapy trials using MLV vectors. PMID:24501411
Park, Seo Yeon; Kim, Eun Joo; Cheon, Keun-Ah
2015-10-01
The purpose of this study is to examine the relationship between 5-HTTLPR polymorphism (44-bp insertion/deletion polymorphism of serotonin transporter gene) and methylphenidate (MPH) treatment response, as well as the association between the adverse events of MPH treatment and 5-HTTLPR polymorphism in children with attention-deficit/hyperactivity disorder (ADHD). A total of 114 children with ADHD (mean age 9.08 ± 1.94 years) were recruited from the child psychiatric clinic in a hospital in South Korea. We have extracted the genomic DNA of the subjects from their blood lymphocytes and analyzed 5-HTTLPR polymorphism of the SLC6A4 gene. All children were treated with MPH for 8 weeks, with clinicians monitoring both the improvement of ADHD symptoms and the side effects. We compared the response to MPH treatment and adverse events among those with the genotype of 5-HRRLPR polymorphism. There was no significant association between the 5-HTTLPR genotype and the response to MPH treatment in children with ADHD. Subjects with the S/L+L/L genotype tended to have tics and nail biting (respectively, p < 0.001, p = 0.017). The results of this study do not support the association between the 5-HTTLPR polymorphism and treatment response with MPH in ADHD. However, our findings suggest the association between 5-HTTLPR polymorphism and the occurrence of tics and nail-biting as an adverse event of methylphenidate. This may aid in our understanding of the genetic contribution and genetic susceptibility of a particular allele in those ADHD patients with tics or nail biting.
Park, Seo Yeon; Kim, Eun Joo
2015-01-01
Abstract Objectives: The purpose of this study is to examine the relationship between 5-HTTLPR polymorphism (44-bp insertion/deletion polymorphism of serotonin transporter gene) and methylphenidate (MPH) treatment response, as well as the association between the adverse events of MPH treatment and 5-HTTLPR polymorphism in children with attention-deficit/hyperactivity disorder (ADHD). Methods: A total of 114 children with ADHD (mean age 9.08 ± 1.94 years) were recruited from the child psychiatric clinic in a hospital in South Korea. We have extracted the genomic DNA of the subjects from their blood lymphocytes and analyzed 5-HTTLPR polymorphism of the SLC6A4 gene. All children were treated with MPH for 8 weeks, with clinicians monitoring both the improvement of ADHD symptoms and the side effects. We compared the response to MPH treatment and adverse events among those with the genotype of 5-HRRLPR polymorphism. Results: There was no significant association between the 5-HTTLPR genotype and the response to MPH treatment in children with ADHD. Subjects with the S/L+L/L genotype tended to have tics and nail biting (respectively, p < 0.001, p = 0.017). Conclusions: The results of this study do not support the association between the 5-HTTLPR polymorphism and treatment response with MPH in ADHD. However, our findings suggest the association between 5-HTTLPR polymorphism and the occurrence of tics and nail-biting as an adverse event of methylphenidate. This may aid in our understanding of the genetic contribution and genetic susceptibility of a particular allele in those ADHD patients with tics or nail biting. PMID:26402385
Kim, Kyu-nam; Kim, Kwang-min; Kim, Bom-taeck; Joo, Nam-seok; Cho, Doo-yeoun; Lee, Duck-joo
2012-04-01
Hypertension (HTN) is a major determinant of various cardiovascular events. Plasma levels of plasminogen activator inhibitor 1 (PAI-1) modulate this risk. A deletion/insertion polymorphism within the PAI-1 loci (4G/4G, 4G/5G, 5G/5G) affects the expression of this gene. The present study investigated the association between PAI-1 loci polymorphisms and HTN in Korean women. Korean women (n = 1312) were enrolled in this study to evaluate the association between PAI-1 4G/5G gene polymorphisms and HTN as well as other metabolic risk factors. PAI-1 loci polymorphisms were investigated using polymerase chain reaction amplification and single-strand conformation polymorphism analysis. The three genotype groups differed with respect to systolic blood pressure (P = 0.043), and diastolic blood pressure (P = 0.009) but not with respect to age, body mass index, total cholesterol, low or high density lipoprotein cholesterol, triglycerides, or fasting blood glucose. Carriers of the PAI-1 4G allele had more hypertension significantly (PAI-1 4G/5G vs. PAI-1 5G/5G, P = 0.032; PAI-1 4G/4G vs. PAI-1 5G/5G, P = 0.034). When stratified according to PAI-1 4G/5G polymorphism, there was no significant difference in all metabolic parameters among PAI-1 genotype groups in patients with HTN as well as subjects with normal blood pressure. The estimated odds ratio of the 4G/4G genotype and 4G/5G for HTN was 1.7 (P = 0.005), and 1.6 (P = 0.015), respectively. These findings might indicate that PAI-1 loci polymorphisms independently contribute to HTN and that gene-environmental interaction may be not associated in Korean women.
Takemoto, Y; Sakatani, M; Takami, S; Tachibana, T; Higaki, J; Ogihara, T; Miki, T; Katsuya, T; Tsuchiyama, T; Yoshida, A; Yu, H; Tanio, Y; Ueda, E
1998-06-01
Serum angiotensin converting enzyme (SACE) is considered to reflect disease activity in sarcoidosis. SACE activity is increased in many patients with active sarcoid lesions. The mechanism for the increased SACE activity in this disease has not been clarified. ACE insertion/deletion (I/D) gene polymorphism has been reported to have an association with SACE levels in sarcoidosis, but no evidence of an association between angiotensin II receptor gene polymorphism and SACE in this disease has been found. A study of the association of angiotensin II receptor gene polymorphisms with sarcoidosis was therefore undertaken. ACE (I/D), angiotensin II type 1 receptor (AGTR1), and angiotensin II type 2 receptor (AGTR2) gene polymorphisms were investigated by polymerase chain reaction (PCR) and SACE levels were measured in three groups of patients: those with sarcoidosis or tuberculosis and normal controls. There was no difference in allele frequency of AGTR1 and AGTR2 polymorphism among the three groups. Neither AGTR1 nor AGTR2 polymorphisms were associated with sarcoidosis. SACE activity was higher in patients with sarcoidosis with the AGTR1 A/C genotype than in others. However, this tendency was not detected in patients with tuberculosis. The AGTR1 allele C is associated with high activity of SACE in patients with sarcoidosis. It is another predisposing factor for high levels of SACE in patients with sarcoidosis and is considered to be an independent factor from the ACE D allele for high levels of SACE in sarcoidosis. This fact could be one of the explanations for the increased SACE activity in sarcoidosis.
Impact of vitamin D receptor gene polymorphisms in pathogenesis of Type-1 diabetes mellitus
Kamel, Mahmoud M; Fouad, Shawky A; Salaheldin, Omina; El-Razek, Abd El-Rahman A Abd; El-Fatah, Abeer I Abd
2014-01-01
Background: Type 1 diabetes mellitus (TIDM) results from an immune-mediated destruction of insulin-producing-cells in the pancreatic islets of Langerhans. There are clear differences in immunogenetic predisposition to type1 diabetes among countries. Studies have indicated that vitamin D supplementation in early childhood decreases the risk of TIDM. Vitamin D exerts its action via the nuclear vitamin D receptor (VDR), which shows an extensive polymorphism. VDR gene polymorphisms have been associated with altered gene expression or gene function. Four single nucleotide polymorphisms (SNPs) in the VDR gene produce variation in four recognition sites. These recognition sites variants include Fok I, Bsm I, Apa I and Taq I. Aim of the study: TO investigate the relationship between VDR gene polymorphisms (at positions Taq I and Apa I) and the incidence of TIDM in Egyptian peoples. Subjects and methods: This study included 74 patients with type 1 DM in addition to 28 healthy age and sex matched control subjects. All of them were subjected to full history taking and clinical examination. Three ml of venous blood were withdrawn from each patient at fasting and postprandial times and used for genomic DNA extraction, estimation of Hb A1C, as well as, fasting and postprandial C-peptide and blood glucose levels. Results: Apa I recognition site was found in low frequency in diabetic patients (14/74) 18.9% while, its frequency was high (16/28) 57.1% among normal subjects. Taq I has two recognition sites. The first was found at nucleotide number 293 that was found in a frequency of (2/28) 7.1% in normal non-diabetic individuals while it was detected in (14/74) 18.9% in diabetic patients. The second Taq I recognition site was found at nucleotide number 494 without any differences between diabetic and normal individuals. Conclusion: This study indicates that there is an association between VDR genetic polymorphism and incidence of TIDM in Egyptian patients. PMID:25664062
Toll-like receptor polymorphisms in malaria-endemic populations
Greene, Jennifer A; Moormann, Ann M; Vulule, John; Bockarie, Moses J; Zimmerman, Peter A; Kazura, James W
2009-01-01
Background Toll-like receptors (TLR) and related downstream signaling pathways of innate immunity have been implicated in the pathogenesis of Plasmodium falciparum malaria. Because of their potential role in malaria pathogenesis, polymorphisms in these genes may be under selective pressure in populations where this infectious disease is endemic. Methods A post-PCR Ligation Detection Reaction-Fluorescent Microsphere Assay (LDR-FMA) was developed to determine the frequencies of TLR2, TLR4, TLR9, MyD88-Adaptor Like Protein (MAL) single nucleotide polymorphisms (SNPs), and TLR2 length polymorphisms in 170 residents of two regions of Kenya where malaria transmission is stable and high (holoendemic) or episodic and low, 346 residents of a malaria holoendemic region of Papua New Guinea, and 261 residents of North America of self-identified ethnicity. Results The difference in historical malaria exposure between the two Kenyan sites has significantly increased the frequency of malaria protective alleles glucose-6-phoshpate dehydrogenase (G6PD) and Hemoglobin S (HbS) in the holoendemic site compared to the episodic transmission site. However, this study detected no such difference in the TLR2, TLR4, TLR9, and MAL allele frequencies between the two study sites. All polymorphisms were in Hardy Weinberg Equilibrium in the Kenyan and Papua New Guinean populations. TLR9 SNPs and length polymorphisms within the TLR2 5' untranslated region were the only mutant alleles present at a frequency greater than 10% in all populations. Conclusion Similar frequencies of TLR2, TLR4, TLR9, and MAL genetic polymorphisms in populations with different histories of malaria exposure suggest that these innate immune pathways have not been under strong selective pressure by malaria. Genotype frequencies are consistent with Hardy-Weinberg Equilibrium and the Neutral Theory, suggesting that genetic drift has influenced allele frequencies to a greater extent than selective pressure from malaria or any other infectious agents in these populations. PMID:19317913
Zhu, Li-Ping; Yue, Xin-Jing; Han, Kui; Li, Zhi-Feng; Zheng, Lian-Shuai; Yi, Xiu-Nan; Wang, Hai-Long; Zhang, You-Ming; Li, Yue-Zhong
2015-07-22
Exotic genes, especially clustered multiple-genes for a complex pathway, are normally integrated into chromosome for heterologous expression. The influences of insertion sites on heterologous expression and allotropic expressions of exotic genes on host remain mostly unclear. We compared the integration and expression efficiencies of single and multiple exotic genes that were inserted into Myxococcus xanthus genome by transposition and attB-site-directed recombination. While the site-directed integration had a rather stable chloramphenicol acetyl transferase (CAT) activity, the transposition produced varied CAT enzyme activities. We attempted to integrate the 56-kb gene cluster for the biosynthesis of antitumor polyketides epothilones into M. xanthus genome by site-direction but failed, which was determined to be due to the insertion size limitation at the attB site. The transposition technique produced many recombinants with varied production capabilities of epothilones, which, however, were not paralleled to the transcriptional characteristics of the local sites where the genes were integrated. Comparative transcriptomics analysis demonstrated that the allopatric integrations caused selective changes of host transcriptomes, leading to varied expressions of epothilone genes in different mutants. With the increase of insertion fragment size, transposition is a more practicable integration method for the expression of exotic genes. Allopatric integrations selectively change host transcriptomes, which lead to varied expression efficiencies of exotic genes.
Hogg, Matthew; Seki, Mineaki; Wood, Richard D; Doublié, Sylvie; Wallace, Susan S
2011-01-21
DNA polymerase θ (POLQ, polθ) is a large, multidomain DNA polymerase encoded in higher eukaryotic genomes. It is important for maintaining genetic stability in cells and helping protect cells from DNA damage caused by ionizing radiation. POLQ contains an N-terminal helicase-like domain, a large central domain of indeterminate function, and a C-terminal polymerase domain with sequence similarity to the A-family of DNA polymerases. The enzyme has several unique properties, including low fidelity and the ability to insert and extend past abasic sites and thymine glycol lesions. It is not known whether the abasic site bypass activity is an intrinsic property of the polymerase domain or whether helicase activity is also required. Three "insertion" sequence elements present in POLQ are not found in any other A-family DNA polymerase, and it has been proposed that they may lend some unique properties to POLQ. Here, we analyzed the activity of the DNA polymerase in the absence of each sequence insertion. We found that the pol domain is capable of highly efficient bypass of abasic sites in the absence of the helicase-like or central domains. Insertion 1 increases the processivity of the polymerase but has little, if any, bearing on the translesion synthesis properties of the enzyme. However, removal of insertions 2 and 3 reduces activity on undamaged DNA and completely abrogates the ability of the enzyme to bypass abasic sites or thymine glycol lesions. Copyright © 2010 Elsevier Ltd. All rights reserved.
Kim, Kyung-Seon; Kim, Ghi-Su; Hwang, Joo-Yeon; Lee, Hye-Ja; Park, Mi-Hyun; Kim, Kwang-joong; Jung, Jongsun; Cha, Hyo-Soung; Shin, Hyoung Doo; Kang, Jong-Ho; Park, Eui Kyun; Kim, Tae-Ho; Hong, Jung-Min; Koh, Jung-Min; Oh, Bermseok; Kimm, Kuchan; Kim, Shin-Yoon; Lee, Jong-Young
2007-01-01
Background Osteoporosis is defined as the loss of bone mineral density that leads to bone fragility with aging. Population-based case-control studies have identified polymorphisms in many candidate genes that have been associated with bone mass maintenance or osteoporotic fracture. To investigate single nucleotide polymorphisms (SNPs) that are associated with osteoporosis, we examined the genetic variation among Koreans by analyzing 81 genes according to their function in bone formation and resorption during bone remodeling. Methods We resequenced all the exons, splice junctions and promoter regions of candidate osteoporosis genes using 24 unrelated Korean individuals. Using the common SNPs from our study and the HapMap database, a statistical analysis of deviation in heterozygosity depicted. Results We identified 942 variants, including 888 SNPs, 43 insertion/deletion polymorphisms, and 11 microsatellite markers. Of the SNPs, 557 (63%) had been previously identified and 331 (37%) were newly discovered in the Korean population. When compared SNPs in the Korean population with those in HapMap database, 1% (or less) of SNPs in the Japanese and Chinese subpopulations and 20% of those in Caucasian and African subpopulations were significantly differentiated from the Hardy-Weinberg expectations. In addition, an analysis of the genetic diversity showed that there were no significant differences among Korean, Han Chinese and Japanese populations, but African and Caucasian populations were significantly differentiated in selected genes. Nevertheless, in the detailed analysis of genetic properties, the LD and Haplotype block patterns among the five sub-populations were substantially different from one another. Conclusion Through the resequencing of 81 osteoporosis candidate genes, 118 unknown SNPs with a minor allele frequency (MAF) > 0.05 were discovered in the Korean population. In addition, using the common SNPs between our study and HapMap, an analysis of genetic diversity and deviation in heterozygosity was performed and the polymorphisms of the above genes among the five populations were substantially differentiated from one another. Further studies of osteoporosis could utilize the polymorphisms identified in our data since they may have important implications for the selection of highly informative SNPs for future association studies. PMID:18036257
Zhang, Zhen; Wang, Bao-Jie; Guan, Hong-Yu; Pang, Hao; Xuan, Jin-Feng
2009-11-01
Reducing amplicon sizes has become a major strategy for analyzing degraded DNA typical of forensic samples. However, amplicon sizes in current mini-short tandem repeat-polymerase chain reaction (PCR) and mini-sequencing assays are still not suitable for analysis of severely degraded DNA. In this study, we present a multiplex typing method that couples ligase detection reaction with PCR that can be used to identify single nucleotide polymorphisms and small-scale insertion/deletions in a sample of severely fragmented DNA. This method adopts thermostable ligation for allele discrimination and subsequent PCR for signal enhancement. In this study, four polymorphic loci were used to assess the ability of this technique to discriminate alleles in an artificially degraded sample of DNA with fragment sizes <100 bp. Our results showed clear allelic discrimination of single or multiple loci, suggesting that this method might aid in the analysis of extremely degraded samples in which allelic drop out of larger fragments is observed.
Spy: a new group of eukaryotic DNA transposons without target site duplications.
Han, Min-Jin; Xu, Hong-En; Zhang, Hua-Hao; Feschotte, Cédric; Zhang, Ze
2014-06-24
Class 2 or DNA transposons populate the genomes of most eukaryotes and like other mobile genetic elements have a profound impact on genome evolution. Most DNA transposons belong to the cut-and-paste types, which are relatively simple elements characterized by terminal-inverted repeats (TIRs) flanking a single gene encoding a transposase. All eukaryotic cut-and-paste transposons so far described are also characterized by target site duplications (TSDs) of host DNA generated upon chromosomal insertion. Here, we report a new group of evolutionarily related DNA transposons called Spy, which also include TIRs and DDE motif-containing transposase but surprisingly do not create TSDs upon insertion. Instead, Spy transposons appear to transpose precisely between 5'-AAA and TTT-3' host nucleotides, without duplication or modification of the AAATTT target sites. Spy transposons were identified in the genomes of diverse invertebrate species based on transposase homology searches and structure-based approaches. Phylogenetic analyses indicate that Spy transposases are distantly related to IS5, ISL2EU, and PIF/Harbinger transposases. However, Spy transposons are distinct from these and other DNA transposon superfamilies by their lack of TSD and their target site preference. Our findings expand the known diversity of DNA transposons and reveal a new group of eukaryotic DDE transposases with unusual catalytic properties. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Yoo, Tae Keun; Han, Sueng-Han; Han, Jinu
2017-12-01
To determine the efficacy of a biodegradable Ologen (Aeon Astron Europe BV, Leiden, The Netherlands) collagen matrix in reducing the blue color change due to exposed thinned sclera after strabismus surgery. Fourteen patients with intermittent exotropia undergoing symmetric bilateral lateral rectus recession surgery were included in this prospective, randomized, paired-eye controlled study. In each patient, Ologen was implanted at the original rectus insertion site in one randomly selected eye; the other eye underwent conventional surgery. Ologen was inserted under the conjunctiva without suturing, covering the muscle insertion site. Conjunctival color change was analyzed using computer-based image analysis immediately and 1 week, 1 month, and 3 months postoperatively. Slit-lamp photographs of each eye were evaluated using contrast limited adaptive histogram equalization (CLAHE), Canny edge, and the RGB (red-green-blue) model. Secondary outcomes were conjunctival and sclera thickness 3 months postoperatively determined by anterior segment optical coherence tomography. Immediately and 1 week postoperatively all color models showed no significant differences between Ologen-implanted and control eyes. Three months postoperatively, Ologen-implanted eyes exhibited significantly lower CLAHE (P = 0.041) and RGB model blue color (P = 0.008) values than control eyes. Canny edge (P = 0.061) and RGB model red color (P = 0.152) values did not differ between eyes. Conjunctival stroma and episcleral complex thickness was greater in Ologen-implanted eyes than in controls (P = 0.001). Blue color change was significantly less noticeable in Ologen-implanted eyes than in controls. Thus, Ologen implantation helps prevent visible blue sclera at the original rectus insertion site after lateral rectus recession. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.
Chen, Ying-Hsin; Liu, Jui-Ming; Hsu, Ren-Jun; Hu, Sheng-Chuan; Harn, Horng-Jyh; Chen, Shee-Ping; Jeng, Jing-Ren; Wu, Chieh-Lin; Ho, Jar-Yi; Yu, Cheng-Ping
2012-02-15
Angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphisms have been associated with acute coronary syndrome (ACS); however, several controversial results have also been found in different studied populations. This hospital-based, emergency room, case-control study in Taiwan retrospectively investigated 111 ACS patients, and 195 non-coronary subjects as a control group, to study the effects of ACE I/D polymorphism in the most urgent ACS patients. ACE I/D polymorphisms were determined by polymerase chain reaction-based assays and their associations with ACS risk, severity, and sudden cardiac death were determined. The ACE DD genotype was associated with ACS incidence. The DD genotype was associated with a significant 4-fold higher risk of ACS in multivariate analysis (odds ratio (OR) = 4.295; 95% confidence interval (CI): 1.436-12.851, p = 0.009), and a 3.35-fold higher risk of acute myocardial infarction. DD genotype carriers also had more than 3-fold higher risks of stenosis in all the three coronary arteries, left anterior descending artery infarction, and anterior wall infarction. In addition, the DD genotype was also associated with a higher risk of sudden cardiac death (OR = 6.484, 95% CI: 1.036-40.598, p = 0.046). This study demonstrated that the ACE DD genotype is an independent risk factor for ACS, and in particular, for acute myocardial infarction. In addition, the ACE DD genotype is also associated with greater ACS severity and a higher risk of sudden cardiac death. ACE genotyping is recommended for patients with a history of ACS, and more intensive preventive care is suggested for patients with the DD genotype.
Pattaradilokrat, Sittiporn; Trakoolsoontorn, Chawinya; Simpalipan, Phumin; Warrit, Natapot; Kaewthamasorn, Morakot; Harnyuttanakorn, Pongchai
2018-01-22
The glutamate-rich protein (GLURP) of the malaria parasite Plasmodium falciparum is a key surface antigen that serves as a component of a clinical vaccine. Moreover, the GLURP gene is also employed routinely as a genetic marker for malarial genotyping in epidemiological studies. While extensive size polymorphisms in GLURP are well recorded, the extent of the sequence diversity of this gene is rarely investigated. The present study aimed to explore the genetic diversity of GLURP in natural populations of P. falciparum. The polymorphic C-terminal repetitive R2 region of GLURP sequences from 65 P. falciparum isolates in Thailand were generated and combined with the data from 103 worldwide isolates to generate a GLURP database. The collection was comprised of 168 alleles, encoding 105 unique GLURP subtypes, characterized by 18 types of amino acid repeat units (AAU). Of these, 28 GLURP subtypes, formed by 10 AAU types, were detected in P. falciparum in Thailand. Among them, 19 GLURP subtypes and 2 AAU types are described for the first time in the Thai parasite population. The AAU sequences were highly conserved, which is likely due to negative selection. Standard Fst analysis revealed the shared distributions of GLURP types among the P. falciparum populations, providing evidence of gene flow among the different demographic populations. Sequence diversity causing size variations in GLURP in Thai P. falciparum populations were detected, and caused by non-synonymous substitutions in repeat units and some insertion/deletion of aspartic acid or glutamic acid codons between repeat units. The P. falciparum population structure based on GLURP showed promising implications for the development of GLURP-based vaccines and for monitoring vaccine efficacy.
AL-HARRAS, MOHAMMAD F.; HOUSSEN, MAHA E.; SHAKER, MOHAMED E.; FARAG, KAMEL; FAROUK, OMAR; MONIR, REHAN; EL-MAHDY, RASHA; ABO-HASHEM, EKBAL M.
2016-01-01
Polymorphisms in antioxidant enzymes and innate immune receptors have been implicated in the development of various types of cancer. The present study aimed to investigate whether polymorphisms of glutathione S-transferase π 1 (GSTP1) and toll-like receptors (TLRs) 2 and 9 are associated with susceptibility to breast cancer among females. The study was conducted on 72 Egyptian female patients with breast cancer, along with 100 healthy volunteers. Polymorphisms of GSTP1 (codon 105 Ile/Val) and TLR9 rs187084 (1237T/C) genes were assessed by polymerase chain reaction (PCR)-restriction fragment length polymorphism, while the −196 to −174 deletion/insertion (del/ins) polymorphism of TLR2 was detected by PCR. The results indicated a decrease in GSTP1 Val allele frequency in breast cancer patients compared with healthy controls, at rates of 22.9 vs. 32.5%, respectively. In addition, the breast cancer group demonstrated a decreased TLR9 C allele frequency compared with the control group, at rates of 36.1 vs. 51.5%, respectively (P=0.0047). A non-significant difference was detected in the frequency of the TLR2 −196 to −174 del allele in breast cancer patients when compared to normal controls. In conclusion, these results suggested that the GSTP1 Val and TLR9 1237C alleles, but not TLR2 −196 to −174 del, are likely to be associated with breast cancer development among females. PMID:26998146
Al-Harras, Mohammad F; Houssen, Maha E; Shaker, Mohamed E; Farag, Kamel; Farouk, Omar; Monir, Rehan; El-Mahdy, Rasha; Abo-Hashem, Ekbal M
2016-03-01
Polymorphisms in antioxidant enzymes and innate immune receptors have been implicated in the development of various types of cancer. The present study aimed to investigate whether polymorphisms of glutathione S-transferase π 1 (GSTP1) and toll-like receptors (TLRs) 2 and 9 are associated with susceptibility to breast cancer among females. The study was conducted on 72 Egyptian female patients with breast cancer, along with 100 healthy volunteers. Polymorphisms of GSTP1 (codon 105 Ile/Val) and TLR9 rs187084 (1237T/C) genes were assessed by polymerase chain reaction (PCR)-restriction fragment length polymorphism, while the -196 to -174 deletion/insertion (del/ins) polymorphism of TLR2 was detected by PCR. The results indicated a decrease in GSTP1 Val allele frequency in breast cancer patients compared with healthy controls, at rates of 22.9 vs. 32.5%, respectively. In addition, the breast cancer group demonstrated a decreased TLR9 C allele frequency compared with the control group, at rates of 36.1 vs. 51.5%, respectively (P=0.0047). A non-significant difference was detected in the frequency of the TLR2 -196 to -174 del allele in breast cancer patients when compared to normal controls. In conclusion, these results suggested that the GSTP1 Val and TLR9 1237C alleles, but not TLR2 -196 to -174 del, are likely to be associated with breast cancer development among females.
Liu, Guohui; Zhou, Tian-Biao; Jiang, Zongpei; Zheng, Dongwen
2015-03-01
The association of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism with type-2 diabetic nephropathy (T2DN) susceptibility and the risk of type-2 diabetes mellitus (T2DM) developing into T2DN in Caucasian populations is still controversial. A meta-analysis was performed to evaluate the association of ACE I/D gene polymorphism with T2DN susceptibility and the risk of T2DM developing into T2DN in Caucasian populations. A predefined literature search and selection of eligible relevant studies were performed to collect data from electronic databases. Sixteen articles were identified for the analysis of the association of ACE I/D gene polymorphism with T2DN susceptibility and the risk of T2DM developing into T2DN in Caucasian populations. ACE I/D gene polymorphism was not associated with T2DN susceptibility and the risk of patients with T2DM developing T2DN in Caucasian populations. Sensitivity analysis according to sample size of case (<100 vs. ≥100) was also performed, and the results were similar to the non-sensitivity analysis. ACE I/D gene polymorphism was not associated with T2DN susceptibility and the risk of patients with T2DM developing T2DN in Caucasian populations. However, more studies should be performed in the future. © The Author(s) 2014.
Chwialkowska, Karolina; Korotko, Urszula; Kosinska, Joanna; Szarejko, Iwona; Kwasniewski, Miroslaw
2017-01-01
Epigenetic mechanisms, including histone modifications and DNA methylation, mutually regulate chromatin structure, maintain genome integrity, and affect gene expression and transposon mobility. Variations in DNA methylation within plant populations, as well as methylation in response to internal and external factors, are of increasing interest, especially in the crop research field. Methylation Sensitive Amplification Polymorphism (MSAP) is one of the most commonly used methods for assessing DNA methylation changes in plants. This method involves gel-based visualization of PCR fragments from selectively amplified DNA that are cleaved using methylation-sensitive restriction enzymes. In this study, we developed and validated a new method based on the conventional MSAP approach called Methylation Sensitive Amplification Polymorphism Sequencing (MSAP-Seq). We improved the MSAP-based approach by replacing the conventional separation of amplicons on polyacrylamide gels with direct, high-throughput sequencing using Next Generation Sequencing (NGS) and automated data analysis. MSAP-Seq allows for global sequence-based identification of changes in DNA methylation. This technique was validated in Hordeum vulgare . However, MSAP-Seq can be straightforwardly implemented in different plant species, including crops with large, complex and highly repetitive genomes. The incorporation of high-throughput sequencing into MSAP-Seq enables parallel and direct analysis of DNA methylation in hundreds of thousands of sites across the genome. MSAP-Seq provides direct genomic localization of changes and enables quantitative evaluation. We have shown that the MSAP-Seq method specifically targets gene-containing regions and that a single analysis can cover three-quarters of all genes in large genomes. Moreover, MSAP-Seq's simplicity, cost effectiveness, and high-multiplexing capability make this method highly affordable. Therefore, MSAP-Seq can be used for DNA methylation analysis in crop plants with large and complex genomes.
Chwialkowska, Karolina; Korotko, Urszula; Kosinska, Joanna; Szarejko, Iwona; Kwasniewski, Miroslaw
2017-01-01
Epigenetic mechanisms, including histone modifications and DNA methylation, mutually regulate chromatin structure, maintain genome integrity, and affect gene expression and transposon mobility. Variations in DNA methylation within plant populations, as well as methylation in response to internal and external factors, are of increasing interest, especially in the crop research field. Methylation Sensitive Amplification Polymorphism (MSAP) is one of the most commonly used methods for assessing DNA methylation changes in plants. This method involves gel-based visualization of PCR fragments from selectively amplified DNA that are cleaved using methylation-sensitive restriction enzymes. In this study, we developed and validated a new method based on the conventional MSAP approach called Methylation Sensitive Amplification Polymorphism Sequencing (MSAP-Seq). We improved the MSAP-based approach by replacing the conventional separation of amplicons on polyacrylamide gels with direct, high-throughput sequencing using Next Generation Sequencing (NGS) and automated data analysis. MSAP-Seq allows for global sequence-based identification of changes in DNA methylation. This technique was validated in Hordeum vulgare. However, MSAP-Seq can be straightforwardly implemented in different plant species, including crops with large, complex and highly repetitive genomes. The incorporation of high-throughput sequencing into MSAP-Seq enables parallel and direct analysis of DNA methylation in hundreds of thousands of sites across the genome. MSAP-Seq provides direct genomic localization of changes and enables quantitative evaluation. We have shown that the MSAP-Seq method specifically targets gene-containing regions and that a single analysis can cover three-quarters of all genes in large genomes. Moreover, MSAP-Seq's simplicity, cost effectiveness, and high-multiplexing capability make this method highly affordable. Therefore, MSAP-Seq can be used for DNA methylation analysis in crop plants with large and complex genomes. PMID:29250096
Badran, Dahlia I; Nada, Hesham; Hassan, Ranya
2015-05-01
The insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene is associated with vitiligo in the Indians and Koreans, but not in those of English or Turkish background. We investigated the ACE (I/D) polymorphism in vitiligo patients for the first time in Egypt and compared serum ACE levels between vitiligo patients and controls. The present study was carried out in 100 vitiligo patients (40 males and 60 females) and in 100 healthy controls of an Egyptian population using the polymerase chain reaction genotyping method. The ACE genotype and allele frequency was significantly different between vitiligo patients and controls. Our results revealed a significant increase in the frequency of the ACE I allele (p=0.002; odds ratio: 1.99; 95% confidence intervals: 1.207-3.284) with an overrepresentation of I/D genotype in the vitiligo patient group. Furthermore, there was a significant difference between the segmental, nonsegmental, and focal vitiligo in ACE gene genotype distribution. Serum ACE levels were significantly increased in vitiligo patients compared to controls (p=0.034). This study suggests that, for the first time, ACE gene polymorphism confers susceptibility to vitiligo in the Egyptian population.
Gene polymorphisms of fibrinolytic enzymes in coal workers' pneumoconiosis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chang, L.C.; Tseng, J.C.; Hua, C.C.
2006-03-15
The authors assessed the gene polymorphisms of missense C/T polymorphism in exon 6 of the urokinase-plasminogen activator (PLAU) gene (PLAU P141L), A/u-repeat in intron 8 of the tissue-type plasminogen activator (PLAT) gene (PLAT TPA25 Alu insertion), and 4G/5G in the promoter region of the serine proteinase inhibitor, clade E (SERPINE) or plasminogen activator inhibitor type 1 gene (SERPINE1 -675 4G/5G) in 153 healthy volunteers and 154 retired coal miners with coal miners' pneumoconiosis (CWP). The CWP subjects included 94 individuals with simple pneumoconiosis and 60 individuals with progressive massive fibrosis presenting with worse pulmonary function. The distributions of genotypes ofmore » these three genes did not differ between the control and CWP subjects or between subjects with simple pneumoconiosis and those with progressive massive fibrosis. However, by assessing duration of work and its interaction with genotypes by means of logistic regression, the authors found the missense C/T polymorphism in exon 6 of the PLAU gene to be an effect modifier of the association between work duration and the development of progressive massive fibrosis.« less
Zalacain, M; Malpartida, F; Pulido, D; Jiménez, A
1987-01-15
The Streptomyces hygroscopicus hyg gene encoding a hygromycin B phosphotransferase has been introduced into different sites of both the Escherichia coli plasmid pBR322 and the Escherichia coli-Saccharomyces cerevisiae shuttle vector YRp7. When this gene was inserted into the BamHI site of pBR322 and then cloned in E. coli phosphorylating activity was not detected, indicating that the hyg gene promoter was not functional in this bacterium. However, when the hyg gene was inserted into either the unique PstI site of pBR322 or into each of the two PstI sites of YRp7, phosphotransferase activity was observed. Analysis of the translation products from these constructions by coupled in vitro transcription-translation systems suggested that in all cases transcrition was regulated by a promoter not provided by the inserted hyg gene and that the synthesized polypeptide was identical to that present in S. hygroscopicus.
Radiological Tenckhoff catheter insertion for peritoneal dialysis: A cost-effective approach.
Lee, James; Mott, Nigel; Mahmood, Usman; Clouston, John; Summers, Kara; Nicholas, Pauline; Gois, Pedro Henrique França; Ranganathan, Dwarakanathan
2018-04-01
Radiological insertion of Tenckhoff catheters can be an alternative option for peritoneal dialysis access creation, as compared to surgical catheter insertion. This study will review the outcomes and complications of radiological Tenckhoff catheter insertion in a metropolitan renal service and compare costs between surgical and radiological insertion. Data were collected prospectively for all patients who had a Tenckhoff catheter insertion for peritoneal dialysis (PD) under radiological guidance at our hospital from May 2014 to November 2016. The type of catheter used and complications, including peri-catheter leak, exit site infection and peritonitis were reviewed. Follow-up data were also collected at points 3, 6 and 12 months from catheter insertion. Costing data were obtained from Queensland Health Electronic Reporting System (QHERS) data, average staff salaries and consumable contract price lists. In the 30-month evaluation period, 70 catheters were inserted. Two patients had an unsuccessful procedure due to the presence of abdominal adhesions. Seven patients had an episode of peri-catheter leak, and four patients had an exit site infection following catheter insertion. Peritonitis was observed in nine patients during the study period. The majority of patients (90%) remained on peritoneal dialysis at 3-month follow-up. The average costs of surgical and radiological insertion were noted to be AUD$7788.34 and AUD$1597.35, respectively. Radiological Tenckhoff catheter insertion for peritoneal dialysis appears to be an attractive and cost-effective option given less waiting periods for the procedure, the relatively low cost of insertion and comparable rates of complications. © 2017 The Royal Australian and New Zealand College of Radiologists.
Tzvetkov, Mladen V; Becker, Christian; Kulle, Bettina; Nürnberg, Peter; Brockmöller, Jürgen; Wojnowski, Leszek
2005-02-01
Whole-genome DNA amplification by multiple displacement (MD-WGA) is a promising tool to obtain sufficient DNA amounts from samples of limited quantity. Using Affymetrix' GeneChip Human Mapping 10K Arrays, we investigated the accuracy and allele amplification bias in DNA samples subjected to MD-WGA. We observed an excellent concordance (99.95%) between single-nucleotide polymorphisms (SNPs) called both in the nonamplified and the corresponding amplified DNA. This concordance was only 0.01% lower than the intra-assay reproducibility of the genotyping technique used. However, MD-WGA failed to amplify an estimated 7% of polymorphic loci. Due to the algorithm used to call genotypes, this was detected only for heterozygous loci. We achieved a 4.3-fold reduction of noncalled SNPs by combining the results from two independent MD-WGA reactions. This indicated that inter-reaction variations rather than specific chromosomal loci reduced the efficiency of MD-WGA. Consistently, we detected no regions of reduced amplification, with the exception of several SNPs located near chromosomal ends. Altogether, despite a substantial loss of polymorphic sites, MD-WGA appears to be the current method of choice to amplify genomic DNA for array-based SNP analyses. The number of nonamplified loci can be substantially reduced by amplifying each DNA sample in duplicate.
[Central venous catheter-related infections in critically ill patients].
Diener, J R; Coutinho, M S; Zoccoli, C M
1996-01-01
To determine incidence rate, etiology and risk factors for central venous catheter (CVC)-related infections in critically-ill patients, a prospective cohort study was conducted in the general Intensive Care Unit (ICU) of a 212 bed Hospital in Florianópolis, Brazil. Patients admitted to ICU between May 1993 and February 1994, exposed to short-term CVC, were included in the study. Quantitative skin culture at CVC insertion site, semi-quantitative CVC tip culture, quantitative hub culture, and peripheral blood-culture were done. Results were submitted to univariate and multivariate analysis. Fifty-seven catheterization periods were analysed in 51 patients. The incidence rate was 21.1% (33.1 per 1,000 catheter-days) for local infection, and 8.7% (14.1 per 1,000 catheter-days) for catheter-associated bacteremia. The skin at the insertion site was colonized in 32.7% and the hub in 29.1% of the patients respectively. Potential sources of infection were the skin in 41.2% of the cases, the hub in 29.4%, remote site in 5.9% and unknown in 23.5%. The hub was implicated in 60% of the catheter-associated bacteremias. Coagulase-negative staphylococci were the main isolates. Another intravascular device and purulence at the insertion site were independently associated with local infection. Insertion at internal jugular site and hub colonization were independently associated with bacteremia. Catheter-associated bacteremia is a major complication of central venous catheterization in critically-ill patients. Internal jugular insertion and CVC hub colonization are important risk factors for significant catheter-related infections.
Gramer, Irina; Kessler, Martin; Geyer, Joachim
2016-06-01
Tyrosine kinase inhibitors (TKIs) that specifically target cKIT represent a therapeutic approach for non-resectable canine mast cell tumours (MCTs) grade II/III. The therapeutic benefit of TKIs has been investigated in other tumours based on clinical response rates and identification of gain-of-function mutations. In the present study, cKIT expression in 14 dogs with osteosarcoma, melanoma, haemangiosarcoma, lymphoma, and fibrosarcoma was analysed. Tissue samples were used for cKIT sequencing to (I) detect the cKIT transcript and to (II) identify gain-of-function mutations. The cKIT transcript was detected in ten patients. Four novel amino acid substitutions and five silent polymorphisms were identified. Furthermore, an insertion mutation (GNSK) was discovered in the tissue, but not in the blood sample of one dog. CKIT expression was identified in a variety of canine tumours and, therefore, TKIs might have a broader therapeutic indication apart from treatment of MCTs. Further investigations will be necessary to localize the cKIT protein in the respective tumours and to evaluate the functional consequence of the cKIT variants identified in the present study.
Quantifying the Number of Independent Organelle DNA Insertions in Genome Evolution and Human Health.
Hazkani-Covo, Einat; Martin, William F
2017-05-01
Fragments of organelle genomes are often found as insertions in nuclear DNA. These fragments of mitochondrial DNA (numts) and plastid DNA (nupts) are ubiquitous components of eukaryotic genomes. They are, however, often edited out during the genome assembly process, leading to systematic underestimation of their frequency. Numts and nupts, once inserted, can become further fragmented through subsequent insertion of mobile elements or other recombinational events that disrupt the continuity of the inserted sequence relative to the genuine organelle DNA copy. Because numts and nupts are typically identified through sequence comparison tools such as BLAST, disruption of insertions into smaller fragments can lead to systematic overestimation of numt and nupt frequencies. Accurate identification of numts and nupts is important, however, both for better understanding of their role during evolution, and for monitoring their increasingly evident role in human disease. Human populations are polymorphic for 141 numt loci, five numts are causal to genetic disease, and cancer genomic studies are revealing an abundance of numts associated with tumor progression. Here, we report investigation of salient parameters involved in obtaining accurate estimates of numt and nupt numbers in genome sequence data. Numts and nupts from 44 sequenced eukaryotic genomes reveal lineage-specific differences in the number, relative age and frequency of insertional events as well as lineage-specific dynamics of their postinsertional fragmentation. Our findings outline the main technical parameters influencing accurate identification and frequency estimation of numts in genomic studies pertinent to both evolution and human health. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Straub, Shannon C.K.; Fishbein, Mark; Liston, Aaron
2015-01-01
Despite knowledge that concerted evolution of high-copy loci is often imperfect, studies that investigate the extent of intragenomic polymorphisms and comparisons across a large number of species are rarely made. We present a bioinformatic pipeline for characterizing polymorphisms within an individual among copies of a high-copy locus. Results are presented for nuclear ribosomal DNA (nrDNA) across the milkweed genus, Asclepias. The 18S-26S portion of the nrDNA cistron of Asclepias syriaca served as a reference for assembly of the region from 124 samples representing 90 species of Asclepias. Reads were mapped back to each individual’s consensus and at each position reads differing from the consensus were tallied using a custom perl script. Low frequency polymorphisms existed in all individuals (mean = 5.8%). Most nrDNA positions (91%) were polymorphic in at least one individual, with polymorphic sites being less frequent in subunit regions and loops. Highly polymorphic sites existed in each individual, with highest abundance in the “noncoding” ITS regions. Phylogenetic signal was present in the distribution of intragenomic polymorphisms across the genus. Intragenomic polymorphisms in nrDNA are common in Asclepias, being found at higher frequency than any other study to date. The high and variable frequency of polymorphisms across species highlights concerns that phylogenetic applications of nrDNA may be error-prone. The new analytical approach provided here is applicable to other taxa and other high-copy regions characterized by low coverage genome sequencing (genome skimming). PMID:25653903
USDA-ARS?s Scientific Manuscript database
Newcastle disease virus (NDV), avian paramyxovirus type 1, has been developed as a vector to express foreign genes for vaccine and gene therapy purposes. The foreign genes are usually inserted into a non-coding region of the NDV genome as an independent transcription unit (ITU), which potentially a...