The Large Subunit rDNA Sequence of Plasmodiophora brassicae Does not Contain Intra-species Polymorphism

PubMed Central

Schwelm, Arne; Berney, Cédric; Dixelius, Christina; Bass, David; Neuhauser, Sigrid

2016-01-01

Clubroot disease caused by Plasmodiophora brassicae is one of the most important diseases of cultivated brassicas. P. brassicae occurs in pathotypes which differ in the aggressiveness towards their Brassica host plants. To date no DNA based method to distinguish these pathotypes has been described. In 2011 polymorphism within the 28S rDNA of P. brassicae was reported which potentially could allow to distinguish pathotypes without the need of time-consuming bioassays. However, isolates of P. brassicae from around the world analysed in this study do not show polymorphism in their LSU rDNA sequences. The previously described polymorphism most likely derived from soil inhabiting Cercozoa more specifically Neoheteromita-like glissomonads. Here we correct the LSU rDNA sequence of P. brassicae. By using FISH we demonstrate that our newly generated sequence belongs to the causal agent of clubroot disease. PMID:27750174

Detection of DNA methylation changes in micropropagated banana plants using methylation-sensitive amplification polymorphism (MSAP).

PubMed

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.

GEOGRAPHIC DISTRIBUTION OF MOLECULAR VARIANCE WITHIN THE BLUE MARLIN (MAKAIRA NIGRICANS): A HIERARCHICAL ANALYSIS OF ALLOZYME, SINGLE-COPY NUCLEAR DNA, AND MITOCHONDRIAL DNA MARKERS.

PubMed

Buonaccorsi, Vincent P; Reece, Kimberly S; Morgan, Lee W; Graves, John E

1999-04-01

This study presents a comparative hierarchical analysis of variance applied to three classes of molecular markers within the blue marlin (Makaira nigricans). Results are reported from analyses of four polymorphic allozyme loci, four polymorphic anonymously chosen single-copy nuclear DNA (scnDNA) loci, and previously reported restriction fragment length polymorphisms (RFLPs) of mitochondrial DNA (mtDNA). Samples were collected within and among the Atlantic and Pacific Oceans over a period of several years. Although moderate levels of genetic variation were detected at both polymorphic allozyme (H = 0.30) and scnDNA loci (H = 0.37), mtDNA markers were much more diverse (h = 0.85). Allele frequencies were significantly different between Atlantic and Pacific Ocean samples at three of four allozyme loci and three of four scnDNA loci. Estimates of allozyme genetic differentiation (θ O ) ranged from 0.00 to 0.15, with a mean of 0.08. The θ O values for scnDNA loci were similar to those of allozymes, ranging from 0.00 to 0.12 with a mean of 0.09. MtDNA RFLP divergence between oceans (θ O = 0.39) was significantly greater than divergence detected at nuclear loci (95% nuclear confidence interval = 0.04-0.11). The fourfold smaller effective population size of mtDNA and male-mediated gene flow may account for the difference observed between nuclear and mitochondrial divergence estimates. © 1999 The Society for the Study of Evolution.

Association of Mitochondrial DNA 10398 Polymorphism in Invasive Breast Cancer in Malay Population of Peninsular Malaysia

PubMed Central

Tengku Baharudin, Nadiah; Jaafar, Hasnan; Zainuddin, Zafarina

2012-01-01

Background: The mitochondrial DNA (mtDNA) 10398 polymorphism is hypothesised to alter a mitochondrial subunit of the electron transfer chain and is associated with several neurodegenerative disorders and cancers. Methods: In this study, an mtDNA polymorphism at nucleotide position 10398 was screened in 101 Malay female patients with invasive breast cancer and 90 age-matched healthy female controls using minisequencing analysis. Results: The Malay women with the 10398G variant showed a significantly increased risk of invasive breast cancer (OR = 2.29, 95% CI 1.25–4.20, P = 0.007). Immunohistochemistry analysis was conducted to investigate the effect of this polymorphism on the levels of apoptosis in breast cancer cells. The level of Bax (a pro-apoptotic protein) expression was significantly higher than that of Bcl-2 (an anti-apoptotic protein) in patients carrying the G allele (P = 0.016) but not in those carrying the A allele (P = 0.48). Conclusion: Based on these findings, we propose that the mtDNA 10398 polymorphism may be a potential risk marker for breast cancer susceptibility in the Malay population. PMID:22977373

New polymorphisms of Xeroderma Pigmentosum DNA repair genes in myelodysplastic syndrome.

PubMed

Santiago, Sabrina Pinheiro; Junior, Howard Lopes Ribeiro; de Sousa, Juliana Cordeiro; de Paula Borges, Daniela; de Oliveira, Roberta Taiane Germano; Farias, Izabelle Rocha; Costa, Marília Braga; Maia, Allan Rodrigo Soares; da Nóbrega Ito, Mayumi; Magalhães, Silvia Maria Meira; Pinheiro, Ronald Feitosa

2017-07-01

The association between Xeroderma Pigmentosum DNA repair genes (XPA rs1800975, XPC rs2228000, XPD rs1799793 and XPF rs1800067) polymorphisms and myelodysplastic syndrome (MDS) have not been reported. To assess the functional role between these polymorphisms and MDS, we evaluated 189 samples stratified in two groups: 95 bone marrow samples from MDS patients and 94 from healthy elderly volunteers used as controls. Genotypes for all polymorphisms were identified in DNA samples in an allelic discrimination experiment by real-time polymerase chain reaction (qPCR). We also studied the mRNA expression of XPA and XPC genes to evaluate if its polymorphisms were functional in 53 RNAm MDS patients by qPCR methodologies. To the rs2228000 polymorphism, the CT and TT polymorphic genotype were associated with increased odds ratio (OR) of more profound cytopenia (hemoglobin and neutrophils count). To the rs1799793 polymorphism, we found that the GG homozygous wild-type genotype was associated with a decreased chance of developing MDS. We observed low expression of XPA in younger patients, in hypoplastic MDS and patients with abnormal karyotype when presented AG or AA polymorphic genotypes. We also found that there was a statistically significant interaction between the presence of micromegakaryocyte on down regulation of XPC regarding the CT heterozygous genotype of the rs1800975 polymorphism. Our results suggest that new functional polymorphisms of Xeroderma Pigmentosum DNA repair genes in MDS are related to its pathogenesis and prognosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genomic profiling of plastid DNA variation in the Mediterranean olive tree

PubMed Central

2011-01-01

Background Characterisation of plastid genome (or cpDNA) polymorphisms is commonly used for phylogeographic, population genetic and forensic analyses in plants, but detecting cpDNA variation is sometimes challenging, limiting the applications of such an approach. In the present study, we screened cpDNA polymorphism in the olive tree (Olea europaea L.) by sequencing the complete plastid genome of trees with a distinct cpDNA lineage. Our objective was to develop new markers for a rapid genomic profiling (by Multiplex PCRs) of cpDNA haplotypes in the Mediterranean olive tree. Results Eight complete cpDNA genomes of Olea were sequenced de novo. The nucleotide divergence between olive cpDNA lineages was low and not exceeding 0.07%. Based on these sequences, markers were developed for studying two single nucleotide substitutions and length polymorphism of 62 regions (with variable microsatellite motifs or other indels). They were then used to genotype the cpDNA variation in cultivated and wild Mediterranean olive trees (315 individuals). Forty polymorphic loci were detected on this sample, allowing the distinction of 22 haplotypes belonging to the three Mediterranean cpDNA lineages known as E1, E2 and E3. The discriminating power of cpDNA variation was particularly low for the cultivated olive tree with one predominating haplotype, but more diversity was detected in wild populations. Conclusions We propose a method for a rapid characterisation of the Mediterranean olive germplasm. The low variation in the cultivated olive tree indicated that the utility of cpDNA variation for forensic analyses is limited to rare haplotypes. In contrast, the high cpDNA variation in wild populations demonstrated that our markers may be useful for phylogeographic and populations genetic studies in O. europaea. PMID:21569271

Isolation and characterization of new highly polymorphic DNA markers from the Huntington disease region

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

Weber, B.; Hedrick, A.; Andrew, S.

1992-02-01

The defect causing Huntington disease (HD) has been mapped to 4p16.3, distal to the DNA marker D4S10. Subsequently, additional polymorphic markers closer to the HD gene have been isolated, which has led to the establishment of predictive testing programs for individuals at risk for HD. Approximately 17% of persons presenting to the Canadian collaborative study for predictive testing for HD have not received any modification of risk, in part because of limited informativeness of currently available DNA markers. Therefore, more highly polymorphic DNA markers are needed, which well further increase the accuracy and availability of predictive testing, specifically for familiesmore » with complex or incomplete pedigree structures. In addition, new markers are urgently needed in order to refine the breakpoints in the few known recombinant HD chromosomes, which could allow a more accurate localization of the HD gene within 4p16.3 and, therefore, accelerate the cloning of the disease gene. In this study, the authors present the identification and characterization of nine new polymorphic DNA markers, including three markers which detect highly informative multiallelic VNTR-like polymorphisms with PIC values of up to .84. These markers have been isolated from a cloned region of DNA which has been previously mapped approximately 1,000 kb from the 4p telomere.« less

[Application of mtDNA polymorphism in species identification of sarcosaphagous insects].

PubMed

Li, Xiang; Cai, Ji-feng

2011-04-01

Species identification of sarcosaphagous insects is one of the important steps in forensic research based on the knowledge of entomology. Recent studies reveal that the application of molecular biology, especially the mtDNA sequences analysis, works well in the species identification of sarcosaphagous insects. The molecular biology characteristics, structures, polymorphism of mtDNA of sarcosaphagous insects, and the recent studies in species identification of sarcosaphagous insects are reviewed in this article.

Genomic DNA sequence and cytosine methylation changes of adult rice leaves after seeds space flight

NASA Astrophysics Data System (ADS)

Shi, Jinming

In this study, cytosine methylation on CCGG site and genomic DNA sequence changes of adult leaves of rice after seeds space flight were detected by methylation-sensitive amplification polymorphism (MSAP) and Amplified fragment length polymorphism (AFLP) technique respectively. Rice seeds were planted in the trial field after 4 days space flight on the shenzhou-6 Spaceship of China. Adult leaves of space-treated rice including 8 plants chosen randomly and 2 plants with phenotypic mutation were used for AFLP and MSAP analysis. Polymorphism of both DNA sequence and cytosine methylation were detected. For MSAP analysis, the average polymorphic frequency of the on-ground controls, space-treated plants and mutants are 1.3%, 3.1% and 11% respectively. For AFLP analysis, the average polymorphic frequencies are 1.4%, 2.9%and 8%respectively. Total 27 and 22 polymorphic fragments were cloned sequenced from MSAP and AFLP analysis respectively. Nine of the 27 fragments from MSAP analysis show homology to coding sequence. For the 22 polymorphic fragments from AFLP analysis, no one shows homology to mRNA sequence and eight fragments show homology to repeat region or retrotransposon sequence. These results suggest that although both genomic DNA sequence and cytosine methylation status can be effected by space flight, the genomic region homology to the fragments from genome DNA and cytosine methylation analysis were different.

A Polymorphism in Mitochondrial DNA Associated with IQ?

ERIC Educational Resources Information Center

Skuder, Patricia; And Others

1995-01-01

Of 100 DNA markers examined in an allelic association study, only 1 showed a replicated association with IQ in samples totaling 107 children. How the gene marked by the particular restriction fragment length polymorphism was tracked and its mitochondrial origin identified is described. (SLD)

DNA polymorphism identity determination using flow cytometry

DOEpatents

Nolan, John P.; White, P. Scott; Cai, Hong

2001-01-01

DNA polymorphism identity determination using flow cytometry. Primers designed to be immobilized on microspheres are allowed to anneal to the DNA strand under investigation, and are extended by either DNA polymerase using fluorescent dideoxynucleotides or ligated by DNA ligase to fluorescent reporter oligonucleotides. The fluorescence of either the dideoxynucleotide or the reporter oligonucleotide attached to the immobilized primer is measured by flow cytometry, thereby identifying the nucleotide polymorphism on the DNA strand.

The Large Subunit rDNA Sequence of Plasmodiophora brassicae Does not Contain Intra-species Polymorphism.

PubMed

Schwelm, Arne; Berney, Cédric; Dixelius, Christina; Bass, David; Neuhauser, Sigrid

2016-12-01

Clubroot disease caused by Plasmodiophora brassicae is one of the most important diseases of cultivated brassicas. P. brassicae occurs in pathotypes which differ in the aggressiveness towards their Brassica host plants. To date no DNA based method to distinguish these pathotypes has been described. In 2011 polymorphism within the 28S rDNA of P. brassicae was reported which potentially could allow to distinguish pathotypes without the need of time-consuming bioassays. However, isolates of P. brassicae from around the world analysed in this study do not show polymorphism in their LSU rDNA sequences. The previously described polymorphism most likely derived from soil inhabiting Cercozoa more specifically Neoheteromita-like glissomonads. Here we correct the LSU rDNA sequence of P. brassicae. By using FISH we demonstrate that our newly generated sequence belongs to the causal agent of clubroot disease. Copyright © 2016 The Authors. Published by Elsevier GmbH.. All rights reserved.

Genetic diversity analysis of Jatropha curcas L. (Euphorbiaceae) based on methylation-sensitive amplification polymorphism.

PubMed

Kanchanaketu, T; Sangduen, N; Toojinda, T; Hongtrakul, V

2012-04-13

Genetic analysis of 56 samples of Jatropha curcas L. collected from Thailand and other countries was performed using the methylation-sensitive amplification polymorphism (MSAP) technique. Nine primer combinations were used to generate MSAP fingerprints. When the data were interpreted as amplified fragment length polymorphism (AFLP) markers, 471 markers were scored. All 56 samples were classified into three major groups: γ-irradiated, non-toxic and toxic accessions. Genetic similarity among the samples was extremely high, ranging from 0.95 to 1.00, which indicated very low genetic diversity in this species. The MSAP fingerprint was further analyzed for DNA methylation polymorphisms. The results revealed differences in the DNA methylation level among the samples. However, the samples collected from saline areas and some species hybrids showed specific DNA methylation patterns. AFLP data were used, together with methylation-sensitive AFLP (MS-AFLP) data, to construct a phylogenetic tree, resulting in higher efficiency to distinguish the samples. This combined analysis separated samples previously grouped in the AFLP analysis. This analysis also distinguished some hybrids. Principal component analysis was also performed; the results confirmed the separation in the phylogenetic tree. Some polymorphic bands, involving both nucleotide and DNA methylation polymorphism, that differed between toxic and non-toxic samples were identified, cloned and sequenced. BLAST analysis of these fragments revealed differences in DNA methylation in some known genes and nucleotide polymorphism in chloroplast DNA. We conclude that MSAP is a powerful technique for the study of genetic diversity for organisms that have a narrow genetic base.

DNA methylation and methylation polymorphism in ecotypes of Jatropha curcas L. using methylation-sensitive AFLP markers.

PubMed

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.

Evaluation of Genetic Variations in Maize Seedlings Exposed to Electric Field Based on Protein and DNA Markers

PubMed Central

AL-Huqail, Asma A.; Abdelhaliem, Ekram

2015-01-01

The current study analyzed proteins and nuclear DNA of electric fields (ELF) exposed and nonexposed maize seedlings for different exposure periods using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), isozymes, random amplified polymorphic DNA (RAPD), and comet assay, respectively. SDS-PAGE analysis revealed total of 46 polypeptides bands with different molecular weights ranging from 186.20 to 36.00 KDa. It generated distinctive polymorphism value of 84.62%. Leucine-aminopeptidase, peroxidase, and catalase isozymes showed the highest values of polymorphism (100%) based on zymograms number, relative front (R f), and optical intensity while esterase isozyme generated polymorphism value of 83.33%. Amino acids were analyzed using high-performance liquid chromatography, which revealed the presence of 17 amino acids of variable contents ranging from 22.65% to 28.09%. RAPD revealed that 78 amplified DNA products had highly polymorphism value (95.08%) based on band numbers, with variable sizes ranging from 120 to 992 base pairs and band intensity. Comet assay recorded the highest extent of nuclear DNA damage as percentage of tailed DNA (2.38%) and tail moment unit (5.36) at ELF exposure of maize nuclei for 5 days. The current study concluded that the longer ELF exposing periods had genotoxic stress on macromolecules of maize cells and biomarkers used should be augmented for reliable estimates of genotoxicity after exposure of economic plants to ELF stressors. PMID:26180815

Genomic relations among 31 species of Mammillaria haworth (Cactaceae) using random amplified polymorphic DNA.

PubMed

Mattagajasingh, Ilwola; Mukherjee, Arup Kumar; Das, Premananda

2006-01-01

Thirty-one species of Mammillaria were selected to study the molecular phylogeny using random amplified polymorphic DNA (RAPD) markers. High amount of mucilage (gelling polysaccharides) present in Mammillaria was a major obstacle in isolating good quality genomic DNA. The CTAB (cetyl trimethyl ammonium bromide) method was modified to obtain good quality genomic DNA. Twenty-two random decamer primers resulted in 621 bands, all of which were polymorphic. The similarity matrix value varied from 0.109 to 0.622 indicating wide variability among the studied species. The dendrogram obtained from the unweighted pair group method using arithmetic averages (UPGMA) analysis revealed that some of the species did not follow the conventional classification. The present work shows the usefulness of RAPD markers for genetic characterization to establish phylogenetic relations among Mammillaria species.

Polymorphic microsatellite DNA markers for the Florida manatee (Trichechus manatus latirostris)

USGS Publications Warehouse

Pause, K.C.; Nourisson, C.; Clark, A.; Kellogg, M.E.; Bonde, R.K.; McGuire, P.M.

2007-01-01

Florida manatees (Trichechus manatus latirostris) are marine mammals that inhabit the coastal waters and rivers of the southeastern USA, primarily Florida. Previous studies have shown that Florida manatees have low mitochondrial DNA variability, suggesting that nuclear DNA loci are necessary for discriminatory analyses. Here we report 10 polymorphic microsatellite loci with an average of 4.2 alleles per locus, and average heterozygosity of 50.1%. These loci have been developed for use in population studies, parentage assignment, and individual identification. ?? 2007 Blackwell Publishing Ltd.

Excess amino acid polymorphism in mitochondrial DNA: contrasts among genes from Drosophila, mice, and humans.

PubMed

Rand, D M; Kann, L M

1996-07-01

Recent studies of mitochondrial DNA (mtDNA) variation in mammals and Drosophila have shown an excess of amino acid variation within species (replacement polymorphism) relative to the number of silent and replacement differences fixed between species. To examine further this pattern of nonneutral mtDNA evolution, we present sequence data for the ND3 and ND5 genes from 59 lines of Drosophila melanogaster and 29 lines of D. simulans. Of interest are the frequency spectra of silent and replacement polymorphisms, and potential variation among genes and taxa in the departures from neutral expectations. The Drosophila ND3 and ND5 data show no significant excess of replacement polymorphism using the McDonald-Kreitman test. These data are in contrast to significant departures from neutrality for the ND3 gene in mammals and other genes in Drosophila mtDNA (cytochrome b and ATPase 6). Pooled across genes, however, both Drosophila and human mtDNA show very significant excesses of amino acid polymorphism. Silent polymorphisms at ND5 show a significantly higher variance in frequency than replacement polymorphisms, and the latter show a significant skew toward low frequencies (Tajima's D = -1.954). These patterns are interpreted in light of the nearly neutral theory where mildly deleterious amino acid haplotypes are observed as ephemeral variants within species but do not contribute to divergence. The patterns of polymorphism and divergence at charge-altering amino acid sites are presented for the Drosophila ND5 gene to examine the evolution of functionally distinct mutations. Excess charge-altering polymorphism is observed at the carboxyl terminal and excess charge-altering divergence is detected at the amino terminal. While the mildly deleterious model fits as a net effect in the evolution of nonrecombining mitochondrial genomes, these data suggest that opposing evolutionary pressures may act on different regions of mitochondrial genes and genomes.

[Study on once sampling quantitation based on information entropy of ISSR amplified bands of Houttuynia cordata].

PubMed

Wang, Haiqin; Liu, Wenlong; He, Fuyuan; Chen, Zuohong; Zhang, Xili; Xie, Xianggui; Zeng, Jiaoli; Duan, Xiaopeng

2012-02-01

To explore the once sampling quantitation of Houttuynia cordata through its DNA polymorphic bands that carried information entropy, from other form that the expression of traditional Chinese medicine polymorphism, genetic polymorphism, of traditional Chinese medicine. The technique of inter simple sequence repeat (ISSR) was applied to analyze genetic polymorphism of H. cordata samples from the same GAP producing area, the DNA genetic bands were transformed its into the information entropy, and the minimum once sampling quantitation with the mathematical mode was measured. One hundred and thirty-four DNA bands were obtained by using 9 screened ISSR primers to amplify from 46 strains DNA samples of H. cordata from the same GAP, the information entropy was H=0.365 6-0.978 6, and RSD was 14.75%. The once sampling quantitation was W=11.22 kg (863 strains). The "once minimum sampling quantitation" were calculated from the angle of the genetic polymorphism of H. cordata, and a great differences between this volume and the amount from the angle of fingerprint were found.

DNApod: DNA polymorphism annotation database from next-generation sequence read archives.

PubMed

Mochizuki, Takako; Tanizawa, Yasuhiro; Fujisawa, Takatomo; Ohta, Tazro; Nikoh, Naruo; Shimizu, Tokurou; Toyoda, Atsushi; Fujiyama, Asao; Kurata, Nori; Nagasaki, Hideki; Kaminuma, Eli; Nakamura, Yasukazu

2017-01-01

With the rapid advances in next-generation sequencing (NGS), datasets for DNA polymorphisms among various species and strains have been produced, stored, and distributed. However, reliability varies among these datasets because the experimental and analytical conditions used differ among assays. Furthermore, such datasets have been frequently distributed from the websites of individual sequencing projects. It is desirable to integrate DNA polymorphism data into one database featuring uniform quality control that is distributed from a single platform at a single place. DNA polymorphism annotation database (DNApod; http://tga.nig.ac.jp/dnapod/) is an integrated database that stores genome-wide DNA polymorphism datasets acquired under uniform analytical conditions, and this includes uniformity in the quality of the raw data, the reference genome version, and evaluation algorithms. DNApod genotypic data are re-analyzed whole-genome shotgun datasets extracted from sequence read archives, and DNApod distributes genome-wide DNA polymorphism datasets and known-gene annotations for each DNA polymorphism. This new database was developed for storing genome-wide DNA polymorphism datasets of plants, with crops being the first priority. Here, we describe our analyzed data for 679, 404, and 66 strains of rice, maize, and sorghum, respectively. The analytical methods are available as a DNApod workflow in an NGS annotation system of the DNA Data Bank of Japan and a virtual machine image. Furthermore, DNApod provides tables of links of identifiers between DNApod genotypic data and public phenotypic data. To advance the sharing of organism knowledge, DNApod offers basic and ubiquitous functions for multiple alignment and phylogenetic tree construction by using orthologous gene information.

DNApod: DNA polymorphism annotation database from next-generation sequence read archives

PubMed Central

Mochizuki, Takako; Tanizawa, Yasuhiro; Fujisawa, Takatomo; Ohta, Tazro; Nikoh, Naruo; Shimizu, Tokurou; Toyoda, Atsushi; Fujiyama, Asao; Kurata, Nori; Nagasaki, Hideki; Kaminuma, Eli; Nakamura, Yasukazu

2017-01-01

With the rapid advances in next-generation sequencing (NGS), datasets for DNA polymorphisms among various species and strains have been produced, stored, and distributed. However, reliability varies among these datasets because the experimental and analytical conditions used differ among assays. Furthermore, such datasets have been frequently distributed from the websites of individual sequencing projects. It is desirable to integrate DNA polymorphism data into one database featuring uniform quality control that is distributed from a single platform at a single place. DNA polymorphism annotation database (DNApod; http://tga.nig.ac.jp/dnapod/) is an integrated database that stores genome-wide DNA polymorphism datasets acquired under uniform analytical conditions, and this includes uniformity in the quality of the raw data, the reference genome version, and evaluation algorithms. DNApod genotypic data are re-analyzed whole-genome shotgun datasets extracted from sequence read archives, and DNApod distributes genome-wide DNA polymorphism datasets and known-gene annotations for each DNA polymorphism. This new database was developed for storing genome-wide DNA polymorphism datasets of plants, with crops being the first priority. Here, we describe our analyzed data for 679, 404, and 66 strains of rice, maize, and sorghum, respectively. The analytical methods are available as a DNApod workflow in an NGS annotation system of the DNA Data Bank of Japan and a virtual machine image. Furthermore, DNApod provides tables of links of identifiers between DNApod genotypic data and public phenotypic data. To advance the sharing of organism knowledge, DNApod offers basic and ubiquitous functions for multiple alignment and phylogenetic tree construction by using orthologous gene information. PMID:28234924

Lack of association of the two polymorphisms in alpha-2 macroglobulin with Alzheimer disease.

PubMed

Poduslo, S E; Shook, B; Drigalenko, E; Yin, X

2002-06-01

Alzheimer disease is a complex neurodegenerative disorder that is characterized by cognitive decline and distinct neuropathology. The gene for alpha-2 macroglobulin (A2M) on chromosome 12 has two polymorphisms that, in some cases, are associated with Alzheimer disease. We examined these two polymorphisms in our families in the DNA Bank (a collection of DNA samples from families with Alzheimer disease in Texas). Using both association studies and sib transmission/disequilibrium tests, we found no association of the two polymorphisms with the disease in our collection. In addition, we did not find an association of the disease with the two polymorphisms in A2M in a small subset of National Institute of Mental Health (NIMH) families. Thus, our studies do not support the A2M polymorphisms as a risk factor for Alzheimer disease. Copyright 2002 Wiley-Liss, Inc.

Alterations of leaf cell ultrastructures and AFLP DNA profiles in Earth-grown tomato plants propagated from long-term six years Mir-flown seeds

NASA Astrophysics Data System (ADS)

Liu, Min; Xue, Huai; Pan, Yi; Zhang, Chunhua; Lu, Jinying

Leaf cell ultrastructures and DNA variations in the firstand the second-generation of Earthgrown tomato (Lycopersicon esculentun Mill) plants that had been endured a long-term six years spaceflight in the Mir were compared to their ground-based control plants, under observations with a Transmission Electron Microscope and the Amplification Fragment Length Polymorphism (AFLP) analysis. For alterations in the morphological ultrastructures, one plant among the 11 first-generation plants generated from 30 Mir-flown seeds had a three-layered palisade cell structure, while other 10 first-generation plants and all ground-based controls had one-layered palisade cell structure in leaves. Starch grains were larger and in clusters, numbers of starch grains increased in the chloroplasts in the Mir-flown plants. Leaf cells became contracted and deformed, and cell shape patterns were different in the Mir-flown plants. For the leaf genomic DNA alterations, 34 DNA bands were polymorphic with a 1.32% polymorphism among 2582 DNA bands in the first-generation Mir-flown plants. Band types in the spaceflight treated plants were also different from those in the ground-based control. Of 11 survived first-generation plants, 7 spaceflight treated plants (Plant Nos. 1-6 and No. 9) had a same 7 polymorphic bands and a same 0.27%DNA mutation. The DNA mutation rate was greatest in Plants No.10 and No.7 (0.90% and 0.94%), less in Plant No.11 (0.31%) and least in Plant No.8 (0.20%). For the 38 send-generation plants propagated from the No. 5 Mir-flown seed, 6 DNA bands were polymorphic with a 0.23% polymorphism among 2564 amplified DNA bands. Among those 38 second-generation plants amplified by primer pair (E4: ACC, M8: CTT), one DNA band disappeared in 29 second-generation plants and in the original Mir-flown No. 5 plant, compared to the ground-base controls. Among the 38 second-generation plants generated from the Mir-flown No. 5 seed, the DNA band types of 29 second-generation plants were different from that of the ground-base controls and had a same 6 polymorphic bands and a same 0.23% DNA mutation. For the 49 second-generation plants derived from the Mir-flown No. 6 seed, 7 DNA bands were polymorphic with 0.27% polymorphism among 2564 amplified DNA bands. With only one exception among those 49 second-generation plants amplified by primer pair (E3: ACA, M3: CAG), one DNA band disappeared in 48 second-generation plants and in the original Mir-flown No. 6 plant, compared to the ground-based controls. Among the 49 second-generation plants generated from the Mir-flown No. 6 seed, the DNA band types of 48 second-generation plants were different from that of the ground-base controls and had a same 7 polymorphic bands and a same 0.27% DNA mutation. Our results indicated that leaf cell ultrastructures had been altered and heredity variations had been induced by seeds being exposed to a long-term outer-space environment. Further research is needed to elucidate the dynamics and mechanisms resulting in such variations. Plant biology studies in the space environment may open potential approaches to induce mutations and to screen new plant varieties by ground-based selections among spaceflight treated seeds or seedlings.

A LDR-PCR approach for multiplex polymorphisms genotyping of severely degraded DNA with fragment sizes <100 bp.

PubMed

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.

Genomic biomarkers and clinical outcomes of physical activity.

PubMed

Izzotti, Alberto

2011-07-01

Clinical and experimental studies in humans provide evidence that moderate physical activity significantly decreases artery oxidative damage to nuclear DNA, DNA-adducts related to age and dyslipedemia, and mitochondrial DNA damage. Maintenance of adequate mitochondrial function is crucial for preventing lipid accumulation and peroxidation occurring in atherosclerosis. Studies performed on human muscle biopsies analyzing gene expression in living humans reveal that physically active subjects improve the expression of genes involved in mitochondrial function and of related microRNAs. The attenuation of oxidative damage to nuclear and mitochondrial DNA by physical activity resulted in beneficial effects due to polymorphisms of glutathione S-transferases genes. Subjects bearing null GSTM1/T1 polymorphisms have poor life expectancy in the case of being sedentary, which was increased 2.6-fold in case they performed physical activity. These findings indicate that the preventive effect of physical activity undergoes interindividual variation affected by genetic polymorphisms. © 2011 New York Academy of Sciences.

Cross-species amplification of mitochondrial DNA sequence-tagged-site markers in conifers: the nature of polymorphism and variation within and among species in Picea.

PubMed

Jaramillo-Correa, J P; Bousquet, J; Beaulieu, J; Isabel, N; Perron, M; Bouillé, M

2003-05-01

Primers previously developed to amplify specific non-coding regions of the mitochondrial genome in Angiosperms, and new primers for additional non-coding mtDNA regions, were tested for their ability to direct DNA amplification in 12 conifer taxa and to detect sequence-tagged-site (STS) polymorphisms within and among eight species in Picea. Out of 12 primer pairs, nine were successful at amplifying mtDNA in most of the taxa surveyed. In conifers, indels and substitutions were observed for several loci, allowing them to distinguish between families, genera and, in some cases, between species within genera. In Picea, interspecific polymorphism was detected for four loci, while intraspecific variation was observed for three of the mtDNA regions studied. One of these (SSU rRNA V1 region) exhibited indel polymorphisms, and the two others ( nad1 intron b/c and nad5 intron1) revealed restriction differences after digestion with Sau3AI (PCR-RFLP). A fourth locus, the nad4L- orf25 intergenic region, showed a multibanding pattern for most of the spruce species, suggesting a possible gene duplication. Maternal inheritance, expected for mtDNA in conifers, was observed for all polymorphic markers except the intergenic region nad4L- orf25. Pooling of the variation observed with the remaining three markers resulted in two to six different mtDNA haplotypes within the different species of Picea. Evidence for intra-genomic recombination was observed in at least two taxa. Thus, these mitotypes are likely to be more informative than single-locus haplotypes. They should be particularly useful for the study of biogeography and the dynamics of hybrid zones.

Polymorphisms in RAI and in genes of nucleotide and base excision repair are not associated with risk of testicular cancer.

PubMed

Laska, Magdalena J; Nexø, Bjørn A; Vistisen, Kirsten; Poulsen, Henrik Enghusen; Loft, Steffen; Vogel, Ulla

2005-07-28

Testicular cancer has been suggested to be primed in utero and there is familiar occurrence, particularly brothers and sons of men with testicular cancer have increased risk. Although no specific causative genotoxic agents have been identified, variations in DNA repair capacity could be associated with the risk of testicular cancer. A case-control study of 184 testicular cancer cases and 194 population-based controls living in the Copenhagen Greater Area in Denmark was performed. We found that neither polymorphisms in several DNA repair genes nor alleles of several polymorphisms in the chromosomal of region 19q13.2-3, encompassing the genes ASE, ERCC1, RAI and XPD, were associated with risk of testicular cancer in Danish patients. This is in contrast to other cancers, where we reported strong associations between polymorphisms in ERCC1, ASE and RAI and occurrence of basal cell carcinoma, breast cancer and lung. To our knowledge this is the first study of DNA repair gene polymorphisms and risk of testicular cancer.

The Effect of Polymorphisms in DNA Repair Genes and Carcinogen Metabolizers on Leukocyte Telomere Length: A Cohort of Healthy Spanish Smokers.

PubMed

Verde, Zoraida; Reinoso-Barbero, Luis; Chicharro, Luis; Resano, Pilar; Sánchez-Hernández, Ignacio; Rodríguez González-Moro, Jose Miguel; Bandrés, Fernando; Gómez-Gallego, Félix; Santiago, Catalina

2016-04-01

Smoking implies exposure to carcinogenic agents that causes DNA damage, which could be suspected to enhance telomere attrition. To protect and deal with DNA damage, cells possess mechanisms that repair and neutralize harmful substances. Polymorphisms altering DNA repair capacity or carcinogen metabolism may lead to synergistic effects with tobacco carcinogen-induced shorter telomere length independently of cancer interaction. The aim of this study was to explore the association between leukocyte telomere length (LTL) and several genetic polymorphisms in DNA repair genes and carcinogen metabolizers in a cohort of healthy smokers. We evaluated the effect of six genetic polymorphisms in cytochrome P1A1 (Ile462Val), XRCC1 (Arg399Gln), APEX1 (Asp148Glu), XRCC3 (Thr241Met), and XPD (Asp312Asn; Lys751Gln) on LTL in a cohort of 145 healthy smokers in addition to smoking habits. Logistic regression analysis showed an association between XRCC1 399Gln allele and shorter telomere length (OR = 5.03, 95% CI = 1.08% to 23.36%). There were not association between the rest of polymorphisms analyzed and LTL. Continuous exposure to tobacco could overwhelm the DNA repair machinery, making the effect of the polymorphisms that reduce repair capacity more pronounced. Analyzing the function of smoking-induced DNA-repair genes and LTL is an important goal in order to identify therapeutic targets to treat smoking-induced diseases. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

DNA repair genes polymorphisms and genetic susceptibility to Philadelphia-negative myeloproliferative neoplasms in a Portuguese population: The role of base excision repair genes polymorphisms.

PubMed

Azevedo, Ana P; Silva, Susana N; De Lima, João P; Reichert, Alice; Lima, Fernando; Júnior, Esmeraldina; Rueff, José

2017-06-01

The role of base excision repair (BER) genes in Philadelphia-negative (PN)-myeloproliferative neoplasms (MPNs) susceptibility was evaluated by genotyping eight polymorphisms [apurinic/apyrimidinic endodeoxyribonuclease 1, mutY DNA glycosylase, earlier mutY homolog ( E. coli ) (MUTYH), 8-oxoguanine DNA glycosylase 1, poly (ADP-ribose) polymerase (PARP) 1, PARP4 and X-ray repair cross-complementing 1 (XRCC1)] in a case-control study involving 133 Caucasian Portuguese patients. The results did not reveal a correlation between individual BER polymorphisms and PN-MPNs when considered as a whole. However, stratification for essential thrombocythaemia revealed i) borderline effect/tendency to increased risk when carrying at least one variant allele for XRCC1_399 single-nucleotide polymorphism (SNP); ii) decreased risk for Janus kinase 2-positive patients carrying at least one variant allele for XRCC1_399 SNP; and iii) decreased risk in females carrying at least one variant allele for MUTYH SNP. Combination of alleles demonstrated an increased risk to PN-MPNs for one specific haplogroup. These findings may provide evidence for gene variants in susceptibility to MPNs. Indeed, common variants in DNA repair genes may hamper the capacity to repair DNA, thus increasing cancer susceptibility.

DNA repair genes polymorphisms and genetic susceptibility to Philadelphia-negative myeloproliferative neoplasms in a Portuguese population: The role of base excision repair genes polymorphisms

PubMed Central

Azevedo, Ana P.; Silva, Susana N.; De Lima, João P.; Reichert, Alice; Lima, Fernando; Júnior, Esmeraldina; Rueff, José

2017-01-01

The role of base excision repair (BER) genes in Philadelphia-negative (PN)-myeloproliferative neoplasms (MPNs) susceptibility was evaluated by genotyping eight polymorphisms [apurinic/apyrimidinic endodeoxyribonuclease 1, mutY DNA glycosylase, earlier mutY homolog (E. coli) (MUTYH), 8-oxoguanine DNA glycosylase 1, poly (ADP-ribose) polymerase (PARP) 1, PARP4 and X-ray repair cross-complementing 1 (XRCC1)] in a case-control study involving 133 Caucasian Portuguese patients. The results did not reveal a correlation between individual BER polymorphisms and PN-MPNs when considered as a whole. However, stratification for essential thrombocythaemia revealed i) borderline effect/tendency to increased risk when carrying at least one variant allele for XRCC1_399 single-nucleotide polymorphism (SNP); ii) decreased risk for Janus kinase 2-positive patients carrying at least one variant allele for XRCC1_399 SNP; and iii) decreased risk in females carrying at least one variant allele for MUTYH SNP. Combination of alleles demonstrated an increased risk to PN-MPNs for one specific haplogroup. These findings may provide evidence for gene variants in susceptibility to MPNs. Indeed, common variants in DNA repair genes may hamper the capacity to repair DNA, thus increasing cancer susceptibility. PMID:28599464

LPA gene: interaction between the apolipoprotein(a) size ('kringle IV' repeat) polymorphism and a pentanucleotide repeat polymorphism influences Lp(a) lipoprotein level.

PubMed

Røsby, O; Berg, K

2000-01-01

In order to search for factors influencing the Lp(a) lipoprotein level, we have examined the apolipoprotein(a) (apo(a)) size polymorphism as well as a pentanucleotide (TTTTA) repeat polymorphism in the 5' control region of the LPA gene. Lp(a) lipoprotein levels were compared between individuals with different genotypes as defined by pulsed field gel electrophoresis of DNA plugs, and PCR of DNA samples followed by polyacrylamide gel electrophoresis. DNA plugs and DNA were prepared from blood samples collected from blood donors. Twenty-seven different K IV repeat alleles were observed in the 71 women and 92 men from which apo(a) size polymorphism results were obtained. Alleles encoding 26-32 Kringle IV repeats were the most frequent. Alleles encoding seven to 11 TTTTA repeats were detected in the 84 women and 122 men included in the pentanucleotide polymorphism study, and homozygosity for eight TTTTA repeats was the most common genotype. The eight TTTTA repeat allele occurred with almost any apo(a) allele. An inverse relationship between number of K IV repeats and Lp(a) concentration was confirmed. The contributions of the apo(a) size polymorphism and the pentanucleotide repeat polymorphism to the interindividual variance of Lp(a) lipoprotein concentrations were 9.7 and 3.5%, respectively (type IV sum of squares). Nineteen per cent of the variance in Lp(a) lipoprotein level appeared to be the result of the multiplication product (interaction) between the apo(a) size polymorphism and the pentanucleotide repeat polymorphism. The contribution of the apo(a) size polymorphism alone to the variation in Lp(a) lipoprotein level was lower than previously reported. However, the multiplicative interaction effect between the K IV repeat polymorphism and the pentanucleotide repeat polymorphism may be an important factor explaining the variation in Lp(a) lipoprotein levels among the populations.

[The joint applications of DNA chips and single nucleotide polymorphisms in forensic science].

PubMed

Bai, Peng; Tian, Li; Zhou, Xue-ping

2005-05-01

DNA chip technology, being a new high-technology, shows its vigorous life and rapid growth. Single Nucleotide Polymorphisms (SNPs) is the most common diversity in the human genome. It provides suitable genetic markers which play a key role in disease linkage study, pharmacogenomics, forensic medicine, population evolution and immigration study. Their advantage such as being analyzed with DNA chips technology, is predicted to play an important role in the field of forensic medicine, especially in paternity test and individual identification. This report mainly reviews the characteristics of DNA chip and SNPs, and their joint applications in the practice of forensic medicine.

Association between DNA methyltransferase gene polymorphism and Parkinson's disease.

PubMed

Pezzi, Julio Carlos; de Bem, Cintia Monique Boschmann Ens; da Rocha, Tatiane Jacobsen; Schumacher-Schuh, Artur F; Chaves, Marcia Lorena Fagundes; Rieder, Carlos Roberto; Hutz, Mara H; Fiegenbaum, Marilu; Camozzato, Ana Luiza

2017-02-03

Parkinson's disease (PD) is a common and complex neurodegenerative disorder, the second most prevalent, only behind Alzheimer's disease. Recent studies suggest that environmental factors may contribute for neurodegeneration through induction of epigenetic modifications, such as DNA methylation, that is carried out by enzymes, such as DNMT1 and DNMT3B. This present study targeted to investigate the association among DNMT1 and DNMT3B polymorphisms with PD. Five hundred and twenty-two participants (214 PD patients following UK Brain Bank criteria and 308 healthy individuals) were evaluated. DNA was obtained from whole blood and genotypes were detected by an allelic discrimination assay using TaqMan ® MGB probes on a real-time PCR system. The polymorphisms studied were rs2162560 and rs759920 (DNMT1) and rs2424913, rs998382 and rs2424932 (DNMT3B). Was found association between DNMT3B rs2424913 in T allele carriers with PD. The presence of the T allele was associated with PD (OR=1.80, 95% CI 1.16-2.81, p=0.009). No significant difference was observed for others DNMT3B SNPs. Also, no association between PD and the control group were observed for DNMT1 polymorphisms. This is the first study addressing an association between DNMT3B polymorphism and PD. The polymorphism may play a role in the pathogenesis of PD. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

XRCC3 Thr241Met Polymorphism is not Associated with Lung Cancer Risk in a Romanian Population.

PubMed

Catana, Andreea; Pop, Monica; Marginean, Dragos Horea; Blaga, Ioana Cristina; Porojan, Mihai Dumitru; Popp, Radu Anghel; Pop, Ioan Victor

2016-01-01

Deoxyribonucleic Acid (DNA) repair mechanisms play a critical role in protecting the cellular genome against carcinogens. X-ray cross-complementing gene 3 (XRCC3) is involved in DNA repair and therefore certain genetic polymorphisms that occur in DNA repair genes may affect the ability to repair DNA defects and may represent a risk factor in carcinogenesis. The purpose of our study was to investigate the association between XRCC3 gene substitution of Threonine with Methionine in codon 241 of XRCC3 gene (Thr241Met) polymorphism and the risk of lung cancer, in a Romanian population. We recruited 93 healthy controls and 85 patients with lung cancer, all smokers. Thr241Met, XRCC3 gene genotyping was determined by multiplex Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). Statistical analysis (OR, recessive model), did not revealed an increased risk for lung cancer, for the variant 241Met allele and Thr241Met genotypes (p=0.138, OR=0.634, CI=0.348-1.157; p=0.023, OR=0.257, CI=0.085-6.824). Also, there were no positive statistical associations between Thr241Met polymorphism of XRCC3 gene, gender, tobacco and various histopathological tumor type of lung cancer. In conclusion, the results of the study suggest that the XRCC3 gene Thr241Met polymorphism is not associated with an increased risk for the development of lung cancer in this Romanian group.

[Association between genetic polymorphisms of DNA repair genes XRCC1, XPD, XRCC3 and the capacity of DNA repair induce by benzene].

PubMed

Xu, Jianning; Yang, Min; Huang, Huilong; Wang, Quankai

2007-09-01

To explore the correlation between genetic polymorphisms of XRCC1, XPD, XRCC3 and DNA repair capacity induced by benzene. Eighty patients suffered from chronic benzene poisoning were investigated. PCR-RFLP was applied to detect the single nucleotide polymorphisms on C26304T, G27466A, G28152A, G36189A of XRCC1, C22541A, C23591T, A35931C of XPD, C18067T of XRCC3. Cytokinesis-block micronucleus (CBMN) and alkaline comet were applied to detect the DNA repair capacity. The DNA repair capacity of the subjects carrying XPD 35931C variant allele or carrying XRCC3 18067 C/T variant genotype were higher than those carrying corresponding mild genotype. There could be a correlation between polymorphisms of XRCC3 and DNA repair capacity of DNA damage induced by benzene.

DNA methylation polymorphism in a set of elite rice cultivars and its possible contribution to inter-cultivar differential gene expression.

PubMed

Wang, Yongming; Lin, Xiuyun; Dong, Bo; Wang, Yingdian; Liu, Bao

2004-01-01

RAPD (randomly amplified polymorphic DNA) and ISSR (inter-simple sequence repeat) fingerprinting on HpaII/MspI-digested genomic DNA of nine elite japonica rice cultivars implies inter-cultivar DNA methylation polymorphism. Using both DNA fragments isolated from RAPD or ISSR gels and selected low-copy sequences as probes, methylation-sensitive Southern blot analysis confirms the existence of extensive DNA methylation polymorphism in both genes and DNA repeats among the rice cultivars. The cultivar-specific methylation patterns are stably maintained, and can be used as reliable molecular markers. Transcriptional analysis of four selected sequences (RdRP, AC9, HSP90 and MMR) on leaves and roots from normal and 5-azacytidine-treated seedlings of three representative cultivars shows an association between the transcriptional activity of one of the genes, the mismatch repair (MMR) gene, and its CG methylation patterns.

Detection of Variation in Long-Term Micropropagated Mature Pistachio via DNA-Based Molecular Markers.

PubMed

Akdemir, Hülya; Suzerer, Veysel; Tilkat, Engin; Onay, Ahmet; Çiftçi, Yelda Ozden

2016-12-01

Determination of genetic stability of in vitro-grown plantlets is needed for safe and large-scale production of mature trees. In this study, genetic variation of long-term micropropagated mature pistachio developed through direct shoot bud regeneration using apical buds (protocol A) and in vitro-derived leaves (protocol B) was assessed via DNA-based molecular markers. Randomly amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR), and amplified fragment length polymorphism (AFLP) were employed, and the obtained PIC values from RAPD (0.226), ISSR (0.220), and AFLP (0.241) showed that micropropagation of pistachio for different periods of time resulted in "reasonable polymorphism" among donor plant and its 18 clones. Mantel's test showed a consistence polymorphism level between marker systems based on similarity matrices. In conclusion, this is the first study on occurrence of genetic variability in long-term micropropagated mature pistachio plantlets. The obtained results clearly indicated that different marker approaches used in this study are reliable for assessing tissue culture-induced variations in long-term cultured pistachio plantlets.

[Polymorphism of genes encoding proteins of DNA repair vs. occupational and environmental exposure to lead, arsenic and pesticides].

PubMed

Bukowski, Karol; Woźniak, Katarzyna

2018-03-09

Genetic polymorphism is associated with the occurrence of at least 2 different alleles in the locus with a frequency higher than 1% in the population. Among polymorphisms we can find single nucleotide polymorphism (SNP) and polymorphism of variable number of tandem repeats. The presence of certain polymorphisms in genes encoding DNA repair enzymes is associated with the speed and efficiency of DNA repair and can protect or expose humans to the effects provoked by xenobiotics. Chemicals, such as lead, arsenic pesticides are considered to exhibit strong toxicity. There are many different polymorphisms in genes encoding DNA repair enzymes, which determine the speed and efficiency of DNA damage repair induced by these xenobiotics. In the case of lead, the influence of various polymorphisms, such as APE1 (apurinic/apyrimidinic endonuclease 1) (rs1130409), hOGG1 (human 8-oxoguanine glycosylase) (rs1052133), XRCC1 (X-ray repair cross-complementing protein group 1) (rs25487), XRCC1 (rs1799782) and XRCC3 (X-ray repair cross-complementing protein group 3) (rs861539) were described. For arsenic polymorphisms, such as ERCC2 (excision repair cross-complementing) (rs13181), XRCC3 (rs861539), APE1 (rs1130409) and hOGG1 (rs1052133) were examined. As to pesticides, separate and combined effects of polymorphisms in genes encoding DNA repair enzymes, such as XRCC1 (rs1799782), hOGG1 (rs1052133), XRCC4 (X-ray repair cross-complementing protein group 4) (rs28360135) and the gene encoding the detoxification enzyme PON1 paraoxonase (rs662) were reported. Med Pr 2018;69(2):225-235. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Using microarray analysis to evaluate genetic polymorphisms involved in the metabolism of environmental chemicals.

PubMed

Ban, Susumu; Kondo, Tomoko; Ishizuka, Mayumi; Sasaki, Seiko; Konishi, Kanae; Washino, Noriaki; Fujita, Syoichi; Kishi, Reiko

2007-05-01

The field of molecular biology currently faces the need for a comprehensive method of evaluating individual differences derived from genetic variation in the form of single nucleotide polymorphisms (SNPs). SNPs in human genes are generally considered to be very useful in determining inherited genetic disorders, susceptibility to certain diseases, and cancer predisposition. Quick and accurate discrimination of SNPs is the key characteristic of technology used in DNA diagnostics. For this study, we first developed a DNA microarray and then evaluated its efficacy by determining the detection ability and validity of this method. Using DNA obtained from 380 pregnant Japanese women, we examined 13 polymorphisms of 9 genes, which are associated with the metabolism of environmental chemical compounds found in high frequency among Japanese populations. The ability to detect CYP1A1 I462V, CYP1B1 L432V, GSTP1 I105V and AhR R554K gene polymorphisms was above 98%, and agreement rates when compared with real time PCR analysis methods (kappa values) showed high validity: 0.98 (0.96), 0.97 (0.93), 0.90 (0.81), 0.90 (0.91), respectively. While this DNA microarray analysis should prove important as a method for initial screening, it is still necessary that we find better methods for improving the detection of other gene polymorphisms not part of this study.

Comparative analysis of DNA methylation polymorphism in drought sensitive (HPKC2) and tolerant (HPK4) genotypes of horse Gram (Macrotyloma uniflorum).

PubMed

Bhardwaj, Jyoti; Mahajan, Monika; Yadav, Sudesh Kumar

2013-08-01

DNA methylation is known as an epigenetic modification that affects gene expression in plants. Variation in CpG methylation behavior was studied in two natural horse gram (Macrotyloma uniflorum [Lam.] Verdc.) genotypes, HPKC2 (drought-sensitive) and HPK4 (drought-tolerant). The methylation pattern in both genotypes was studied through methylation-sensitive amplified polymorphism. The results revealed that methylation was higher in HPKC2 (10.1%) than in HPK4 (8.6%). Sequencing demonstrated sequence homology with the DRE binding factor (cbf1), the POZ/BTB protein, and the Ty1-copia retrotransposon among some of the polymorphic fragments showing alteration in methylation behavior. Differences in DNA methylation patterns could explain the differential drought tolerance and the epigenetic signature of these two horse gram genotypes.

Global DNA methylation analysis using methyl-sensitive amplification polymorphism (MSAP).

PubMed

Yaish, Mahmoud W; Peng, Mingsheng; Rothstein, Steven J

2014-01-01

DNA methylation is a crucial epigenetic process which helps control gene transcription activity in eukaryotes. Information regarding the methylation status of a regulatory sequence of a particular gene provides important knowledge of this transcriptional control. DNA methylation can be detected using several methods, including sodium bisulfite sequencing and restriction digestion using methylation-sensitive endonucleases. Methyl-Sensitive Amplification Polymorphism (MSAP) is a technique used to study the global DNA methylation status of an organism and hence to distinguish between two individuals based on the DNA methylation status determined by the differential digestion pattern. Therefore, this technique is a useful method for DNA methylation mapping and positional cloning of differentially methylated genes. In this technique, genomic DNA is first digested with a methylation-sensitive restriction enzyme such as HpaII, and then the DNA fragments are ligated to adaptors in order to facilitate their amplification. Digestion using a methylation-insensitive isoschizomer of HpaII, MspI is used in a parallel digestion reaction as a loading control in the experiment. Subsequently, these fragments are selectively amplified by fluorescently labeled primers. PCR products from different individuals are compared, and once an interesting polymorphic locus is recognized, the desired DNA fragment can be isolated from a denaturing polyacrylamide gel, sequenced and identified based on DNA sequence similarity to other sequences available in the database. We will use analysis of met1, ddm1, and atmbd9 mutants and wild-type plants treated with a cytidine analogue, 5-azaC, or zebularine to demonstrate how to assess the genetic modulation of DNA methylation in Arabidopsis. It should be noted that despite the fact that MSAP is a reliable technique used to fish for polymorphic methylated loci, its power is limited to the restriction recognition sites of the enzymes used in the genomic DNA digestion.

Clinical response to chemotherapy in locally advanced breast cancer was not associated with several polymorphisms in detoxification enzymes and DNA repair genes.

PubMed

Saadat, Mostafa; Khalili, Maryam; Nasiri, Meysam; Rajaei, Mehrdad; Omidvari, Shahpour; Saadat, Iraj

2012-03-02

The main aim of the present study was to investigate the association between several genetic polymorphisms (in glutathione S-transferase members and DNA repair genes) and clinical response to chemotherapy in locally advanced breast cancer. A sequential series of 101 patients were prospectively included in this study. Clinical assessment of treatment was accomplished by comparing initial tumor size with preoperative tumor size using revised RECIST guideline (version 1.1). Clinical response was regarded as a response or no response. There was no difference between non-responders and responders for the prevalence of genotypes of the study polymorphisms. Copyright © 2012 Elsevier Inc. All rights reserved.

Identification of apple cultivars on the basis of simple sequence repeat markers.

PubMed

Liu, G S; Zhang, Y G; Tao, R; Fang, J G; Dai, H Y

2014-09-12

DNA markers are useful tools that play an important role in plant cultivar identification. They are usually based on polymerase chain reaction (PCR) and include simple sequence repeats (SSRs), inter-simple sequence repeats, and random amplified polymorphic DNA. However, DNA markers were not used effectively in the complete identification of plant cultivars because of the lack of known DNA fingerprints. Recently, a novel approach called the cultivar identification diagram (CID) strategy was developed to facilitate the use of DNA markers for separate plant individuals. The CID was designed whereby a polymorphic maker was generated from each PCR that directly allowed for cultivar sample separation at each step. Therefore, it could be used to identify cultivars and varieties easily with fewer primers. In this study, 60 apple cultivars, including a few main cultivars in fields and varieties from descendants (Fuji x Telamon) were examined. Of the 20 pairs of SSR primers screened, 8 pairs gave reproducible, polymorphic DNA amplification patterns. The banding patterns obtained from these 8 primers were used to construct a CID map. Each cultivar or variety in this study was distinguished from the others completely, indicating that this method can be used for efficient cultivar identification. The result contributed to studies on germplasm resources and the seedling industry in fruit trees.

Assessment of changes in DNA methylation by methylation-sensitive amplification polymorphism in Jatropha curcas L. subjected to salinity stress.

PubMed

Mastan, Shaik G; Rathore, Mangal S; Bhatt, Vacha D; Yadav, P; Chikara, J

2012-10-15

The present study assesses the changes in DNA methylation in leaf and root tissues of Jatropha curcas L., induced by salinity stress using methylation sensitive amplification polymorphism (MSAP) markers. Seedlings of 21 days (d) grown under controlled conditions were subjected to 0–100 mM salinity treatment for 24 h (1 d). Immediate changes in DNA methylation and polymorphism in methylated DNA in whole genome of both leaves and roots were assessed using 10 selective combinations of MSAP primers. In root and leaves 70.06% and 57.89% methylation was observed respectively. Similarly 67.22% and 71.21% polymorphism was observed in methylated DNA from root and leaf tissues respectively. Compared with control, the percentage of methylation and methylation polymorphism in roots of plants under different dosages of salinity was found in the order of 50 mM < 25 mM = 100 mM < 75 mM and 75 mM < 25 mM < 50 mM < 100 mM respectively. Similarly percentage of methylation and methylation polymorphism in leaves of plants treated with different levels of salinity was found in order of 75 mM < 25 mM < 50 mM < 100 mM and 50 mM < 25 mM < 100 mM < 75 mM respectively. The MSAP analysis showed that under salt stress homologous nucleotide sequences in genome from control and salt treated plants of J. curcas showed different patterns of methylation; which suggest that these fragments probably play an important role to induce immediate adaptive responses in Jatropha under salinity stress.

Association Between Chloroplast DNA and Mitochondrial DNA Haplotypes in Prunus spinosa L. (Rosaceae) Populations across Europe

PubMed Central

MOHANTY, APARAJITA; MARTÍN, JUAN PEDRO; GONZÁLEZ, LUIS MIGUEL; AGUINAGALDE, ITZIAR

2003-01-01

Chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) were studied in 24 populations of Prunus spinosa sampled across Europe. The cpDNA and mtDNA fragments were amplified using universal primers and subsequently digested with restriction enzymes to obtain the polymorphisms. Combinations of all the polymorphisms resulted in 33 cpDNA haplotypes and two mtDNA haplotypes. Strict association between the cpDNA haplotypes and the mtDNA haplotypes was detected in most cases, indicating conjoint inheritance of the two genomes. The most frequent and abundant cpDNA haplotype (C20; frequency, 51 %) is always associated with the more frequent and abundant mtDNA haplotype (M1; frequency, 84 %). All but two of the cpDNA haplotypes associated with the less frequent mtDNA haplotype (M2) are private haplotypes. These private haplotypes are phylogenetically related but geographically unrelated. They form a separate cluster on the minimum‐length spanning tree. PMID:14534199

ERCC2/XPD Lys751Gln alter DNA repair efficiency of platinum-induced DNA damage through P53 pathway.

PubMed

Zhang, Guopei; Guan, Yangyang; Zhao, Yuejiao; van der Straaten, Tahar; Xiao, Sha; Xue, Ping; Zhu, Guolian; Liu, Qiufang; Cai, Yuan; Jin, Cuihong; Yang, Jinghua; Wu, Shengwen; Lu, Xiaobo

2017-02-01

Platinum-based treatment causes Pt-DNA adducts which lead to cell death. The platinum-induced DNA damage is recognized and repaired by the nucleotide excision repair (NER) system of which ERCC2/XPD is a critical enzyme. Single nucleotide polymorphisms in ERCC2/XPD have been found to be associated with platinum resistance. The aim of the present study was to investigate whether ERCC2/XPD Lys751Gln (rs13181) polymorphism is causally related to DNA repair capacity of platinum-induced DNA damage. First, cDNA clones expressing different genotypes of the polymorphism was transfected to an ERCC2/XPD defective CHO cell line (UV5). Second, all cells were treated with cisplatin. Cellular survival rate were investigated by MTT growth inhibition assay, DNA damage levels were investigated by comet assay and RAD51 staining. The distribution of cell cycle and the change of apoptosis rates were detected by a flow cytometric method (FCM). Finally, P53mRNA and phospho-P53 protein levels were further investigated in order to explore a possible explanation. As expected, there was a significantly increased in viability of UV5 ERCC2 (AA) as compared to UV5 ERCC2 (CC) after cisplatin treatment. The DNA damage level of UV5 ERCC2 (AA) was significant decreased compared to UV5 ERCC2 (CC) at 24 h of treatment. Mutation of ERCC2rs13181 AA to CC causes a prolonged S phase in cell cycle. UV5 ERCC2 (AA) alleviated the apoptosis compared to UV5 ERCC2 (CC) , meanwhile P53mRNA levels in UV ERCC2 (AA) was also lower when compared UV5 ERCC2 (CC) . It co-incides with a prolonged high expression of phospho-P53, which is relevant for cell cycle regulation, apoptosis, and the DNA damage response (DDR). We concluded that ERCC2/XPD rs13181 polymorphism is possibly related to the DNA repair capacity of platinum-induced DNA damage. This functional study provides some clues to clarify the relationship between cisplatin resistance and ERCC2/XPDrs13181 polymorphism. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genetic diversity and differentiation in Prunus species (Rosaceae) using chloroplast and mitochondrial DNA CAPS markers.

PubMed

Ben Mustapha, S; Ben Tamarzizt, H; Baraket, G; Abdallah, D; Salhi Hannachi, A

2015-04-27

Chloroplast (cpDNA) and mitochondrial DNA (mtDNA) were analyzed to establish genetic relationships among Tunisian plum cultivars using the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) technique. Two mtDNA regions (nad 1 b/c and nad 4 1/2) and a cpDNA region (trnL-trnF) were amplified and digested using restriction enzymes. Seventy and six polymorphic sites were revealed in cpDNA and mtDNA, respectively. As a consequence, cpDNA appears to be more polymorphic than mtDNA. The unweighted pair group method with arithmetic mean (UPGMA) dendrogram showed that accessions were distributed independently of their geographical origin, and introduced and local cultivars appear to be closely related. Both UPGMA and principal component analysis grouped Tunisian plum accessions into similar clusters. The analysis of the pooled sequences allowed the detection of 17 chlorotypes and 12 mitotypes. The unique haplotypes detected for cultivars are valuable for management and preservation of the plum local resources. From this study, PCR-RFLP analysis appears to be a useful approach to detect and identify cytoplasmic variation in plum trees. Our results also provide useful information for the management of genetic resources and to establish a program to improve the genetic resources available for plums.

DNA repair polymorphisms in B-cell chronic lymphocytic leukemia in sufferers of Chernobyl Nuclear Power Plant accident.

PubMed

Abramenko, Iryna; Bilous, Nadiia; Chumak, Anatolyi; Kostin, Alexey; Martina, Zoya; Dyagil, Iryna

2012-01-01

An association between DNA repair gene polymorphisms, environmental factors, and development of some types of cancer has been suggested by several studies. Chronic lymphocytic leukemia (CLL) is the most common form of leukemia in the clean-up workers of the Chernobyl Nuclear Power Plant (NPP) accident and it has some specific features. Therefore, we have studied the possible differences in DNA repair gene polymorphisms in CLL patients depending on ionizing radiation (IR) exposure history and their clinical characterictics. Arg399Gln XRCC1, Thr241Met XRCC3, and Lys751Gln XPD polymorphisms were studied in 64 CLL patients, exposed to IR due to the Chernobyl NPP accident, 114 IR-non-exposed CLL patients, and 103 sex- and age-matched IR-exposed controls using polymerase chain reaction-restriction fragment-length polymorphism analysis. All investigated polymorphisms were equally distributed between two groups of CLL patients and IR-exposed controls, except that that there was a significant reduction of the common homozygous Lys/Lys XPD genotype among IR-exposed CLL patients (23.7%) compared with IR-exposed controls (45.6%), OR = 0.37; 95% CI = 0.18-0.75; (P = 0.005). The number of IR-non-exposed CLL patients (37.4%) with the Lys/Lys XPD genotype was also decreased compared to IR-exposed controls, although this difference was not significant (P = 0.223). These preliminary data suggest a possible modifying role of Lys751Gln XPD polymorphism for the development of CLL, expecially in radiation-exposed persons.

Use of DNA markers in forest tree improvement research

Treesearch

D.B. Neale; M.E. Devey; K.D. Jermstad; M.R. Ahuja; M.C. Alosi; K.A. Marshall

1992-01-01

DNA markers are rapidly being developed for forest trees. The most important markers are restriction fragment length polymorphisms (RFLPs), polymerase chain reaction- (PCR) based markers such as random amplified polymorphic DNA (RAPD), and fingerprinting markers. DNA markers can supplement isozyme markers for monitoring tree improvement activities such as; estimating...

DNA methylation polymorphism in flue-cured tobacco and candidate markers for tobacco mosaic virus resistance.

PubMed

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.

Molecular evolution of the leptin exon 3 in some species of the family Canidae.

PubMed

Chmurzynska, Agata; Zajac, Magdalena; Switonski, Marek

2003-01-01

The structure of the leptin gene seems to be well conserved. The polymorphism of this gene in four species belonging to the Canidae family (the dog (Canis familiaris)--16 different breeds, the Chinese racoon dog (Nyctereutes procyonoides procyonoides), the red fox (Vulpes vulpes) and the arctic fox (Alopex lagopus)) were studied with the use of single strand conformation polymorphism (SSCP), restriction fragment length polymorphism (RFLP) and DNA sequencing techniques. For exon 2, all species presented the same SSCP pattern, while in exon 3 some differences were found. DNA sequencing of exon 3 revealed the presence of six nucleotide substitutions, differentiating the studied species. Three of them cause amino acid substitutions as well. For all dog breeds studied, SSCP patterns were identical.

[Forensic hematology genetics--paternity testing].

PubMed

Kratzer, A; Bär, W

1997-05-01

In Switzerland paternity investigations are carried out using DNA analysis only since 1991. DNA patterns are inherited and only with the exception of genetically identical twins they are different in everyone and therefore unique to an individual. Hence DNA-systems are an excellent tool to resolve paternity disputes. DNA polymorphisms used for paternity diagnosis are length polymorphisms of the highly polymorphic VNTR loci [variable number of tandem repeats]. The most frequently applied systems are the DNA single locus systems. In addition to the DNA single locus systems the application of PCR (PCR = polymerase chain reaction) based DNA systems has increased particularly in difficult deficiency cases or in cases where only small evidential samples or partially degraded DNA are available. Normally four independent DNA single probes are used to produce a DNA profile from the mother, the child and the alleged father. A child inherits half the DNA patterns from its mother and the other half from its true biological father. If an alleged father doesn't possess the paternal specific DNA pattern in his DNA profile he is excluded from the paternity. In case of non-exclusion the probability for paternity is calculated according to Essen-Möller. When applying four highly polymorphic DNA single locus systems the biostatistical evaluation leads always to W-values exceeding 99.8% [= required value for positive proof of paternity]. DNA analysis is currently the best available method to achieve such effective conclusions in paternity investigations.

DNA fingerprinting of Brassica juncea cultivars using microsatellite probes.

PubMed

Bhatia, S; Das, S; Jain, A; Lakshmikumaran, M

1995-09-01

The genetic variability in the Brassica juncea cultivars was detected by employing in-gel hybridization of restricted DNA to simple repetitive sequences such as (GATA)4, (GACA)4 and (CAC)5. The most informative probe/enzyme combination was (GATA)4/EcoRI, yielding highly polymorphic fingerprint patterns for the B. juncea cultivars. This technique was found to be dependable for establishing the variety specific patterns for most of the cultivars studied, a prerequisite for germplasm preservation. The results of the present study were compared with those reported in our earlier study in which random amplification of polymorphic DNA (RAPD) was used for assessing the genetic variability in the B. juncea cultivars.

Ancestral Polymorphisms and Sex-Biased Migration Shaped the Demographic History of Brown Bears and Polar Bears

PubMed Central

Nakagome, Shigeki; Mano, Shuhei; Hasegawa, Masami

2013-01-01

Recent studies have reported discordant gene trees in the evolution of brown bears and polar bears. Genealogical histories are different among independent nuclear loci and between biparentally inherited autosomal DNA (aDNA) and matrilineal mitochondrial DNA (mtDNA). Based on multi-locus genomic sequences from aDNA and mtDNA, we inferred the population demography of brown and polar bears and found that brown bears have 6 times (aDNA) or more than 14 times (mtDNA) larger population sizes than polar bears and that polar bear lineage is derived from within brown bear diversity. In brown bears, the effective population size ratio of mtDNA to aDNA was at least 0.62, which deviated from the expected value of 0.25, suggesting matriarchal population due to female philopatry and male-biased migration. These results emphasize that ancestral polymorphisms and sex-biased migration may have contributed to conflicting branching patterns in brown and polar bears across aDNA genes and mtDNA. PMID:24236053

Ancestral polymorphisms and sex-biased migration shaped the demographic history of brown bears and polar bears.

PubMed

Nakagome, Shigeki; Mano, Shuhei; Hasegawa, Masami

2013-01-01

Recent studies have reported discordant gene trees in the evolution of brown bears and polar bears. Genealogical histories are different among independent nuclear loci and between biparentally inherited autosomal DNA (aDNA) and matrilineal mitochondrial DNA (mtDNA). Based on multi-locus genomic sequences from aDNA and mtDNA, we inferred the population demography of brown and polar bears and found that brown bears have 6 times (aDNA) or more than 14 times (mtDNA) larger population sizes than polar bears and that polar bear lineage is derived from within brown bear diversity. In brown bears, the effective population size ratio of mtDNA to aDNA was at least 0.62, which deviated from the expected value of 0.25, suggesting matriarchal population due to female philopatry and male-biased migration. These results emphasize that ancestral polymorphisms and sex-biased migration may have contributed to conflicting branching patterns in brown and polar bears across aDNA genes and mtDNA.

Study on DNA Damage Induced by Neon Beam Irradiation in Saccharomyces Cerevisiae

NASA Astrophysics Data System (ADS)

Lu, Dong; Li, Wenjian; Wu, Xin; Wang, Jufang; Ma, Shuang; Liu, Qingfang; He, Jinyu; Jing, Xigang; Ding, Nan; Dai, Zhongying; Zhou, Jianping

2010-12-01

Yeast strain Saccharomyces cerevisiae was irradiated with different doses of 85 MeV/u 20Ne10+ to investigate DNA damage induced by heavy ion beam in eukaryotic microorganism. The survival rate, DNA double strand breaks (DSBs) and DNA polymorphic were tested after irradiation. The results showed that there were substantial differences in DNA between the control and irradiated samples. At the dose of 40 Gy, the yeast cell survival rate approached 50%, DNA double-strand breaks were barely detectable, and significant DNA polymorphism was observed. The alcohol dehydrogenase II gene was amplified and sequenced. It was observed that base changes in the mutant were mainly transversions of T→G and T→C. It can be concluded that heavy ion beam irradiation can lead to change in single gene and may be an effective way to induce mutation.

Associations between sperm quality, DNA damage, and CYP1A1, GSTT1 and GSTM1 polymorphisms with 1-hydroxypyrene urinary levels in men occupationally exposed to polycyclic aromatic hydrocarbons.

PubMed

Recio-Vega, Rogelio; Olivas-Calderon, Edgar; Michel-Ramirez, Gladis; Martinez-Salinas, Rebeca Isabel; Gallegos-Arreola, Martha Patricia; Ocampo-Gomez, Guadalupe Leticia; Perez-Morales, Rebeca

2018-05-29

During recent decades, several reports have suggested a decrease in semen quality and DNA damage due in part to environmental toxicants and industrial chemicals. Among these xenobiotics, polycyclic aromatic hydrocarbons (PAHs) are of particular concern because of their remarkable mutagenic and carcinogenic properties and because several experimental and epidemiological studies have reported adverse effects of PAHs on male reproductive health and DNA structure. The aim of the study was to evaluate the association between 1-hydroxypyrene (1-OHP) urinary levels and sperm quality, DNA damage and the frequency of CYP1A1, GSTT1, and GSTM1 polymorphisms. Semen, urine and blood samples were taken for sperm-quality assessment, 1-OHP urinary level measurement, DNA damage evaluation and polymorphism frequency analysis of three genes implicated in PAH metabolism in a total of 70 Mexican subjects exposed and nonexposed to PAHs. A significant decrease in sperm quality and increased DNA damage were registered in occupationally exposed volunteers. Polymorphisms modified the 1-OHP urinary levels; however, no associations were found between them. Inverse associations were registered between the sperm concentration/mL and 1-OHP levels and between tail lengths and the GSMT1 null genotype. Our data showed an inverse association between 1-OHP urinary levels and both sperm quality and the DNA integrity. Additionally, the heterozygote variants of CYP1A1-m1 and CYP1A1-m2 significantly increased the urinary excretion of 1-OHP, and the GSTM1 null variant was inversely associated with the comet parameters evaluated.

MCT1, MCT4 and CD147 gene polymorphisms in healthy horses and horses with myopathy.

PubMed

Mykkänen, A K; Koho, N M; Reeben, M; McGowan, C M; Pösö, A R

2011-12-01

Polymorphisms in human lactate transporter proteins (monocarboxylate transporters; MCTs), especially the MCT1 isoform, can affect lactate transport activity and cause signs of exercise-induced myopathy. Muscles express MCT1, MCT4 and CD147, an ancillary protein, indispensable for the activity of MCT1 and MCT4. We sequenced the coding sequence (cDNA) of horse MCT4 for the first time and examined polymorphisms in the cDNA of MCT1, MCT4 and CD147 of 16 healthy horses. To study whether signs of myopathy are linked to the polymorphisms, biopsy samples were taken from 26 horses with exercise-induced recurrent myopathy. Two polymorphisms that cause a change in amino acid sequence were found in MCT1 (Val(432)Ile and Lys(457)Gln) and one in CD147 (Met(125)Val). All polymorphisms in MCT4 were silent. Mutations in MCT1 or CD147 in equine muscle were not associated with myopathy. In the future, a functional study design is needed to evaluate the physiological role of the polymorphisms found. Copyright © 2010 Elsevier Ltd. All rights reserved.

Prevalence of K13-propeller gene polymorphisms among Plasmodium falciparum parasites isolated from adult symptomatic patients in northern Uganda.

PubMed

Ocan, Moses; Bwanga, Freddie; Okeng, Alfred; Katabazi, Fred; Kigozi, Edgar; Kyobe, Samuel; Ogwal-Okeng, Jasper; Obua, Celestino

2016-08-19

In the absence of an effective vaccine, malaria treatment and eradication is still a challenge in most endemic areas globally. This is especially the case with the current reported emergence of resistance to artemisinin agents in Southeast Asia. This study therefore explored the prevalence of K13-propeller gene polymorphisms among Plasmodium falciparum parasites in northern Uganda. Adult patients (≥18 years) presenting to out-patients department of Lira and Gulu regional referral hospitals in northern Uganda were randomly recruited. Laboratory investigation for presence of plasmodium infection among patients was done using Plasmodium falciparum exclusive rapid diagnostic test, histidine rich protein-2 (HRP2) (Pf). Finger prick capillary blood from patients with a positive malaria test was spotted on a filter paper Whatman no. 903. The parasite DNA was extracted using chelex resin method and sequenced for mutations in K13-propeller gene using Sanger sequencing. PCR DNA sequence products were analyzed using in DNAsp 5.10.01software, data was further processed in Excel spreadsheet 2007. A total of 60 parasite DNA samples were sequenced. Polymorphisms in the K13-propeller gene were detected in four (4) of the 60 parasite DNA samples sequenced. A non-synonymous polymorphism at codon 533 previously detected in Cambodia was found in the parasite DNA samples analyzed. Polymorphisms at codon 522 (non-synonymous) and codon 509 (synonymous) were also found in the samples analyzed. The study found evidence of positive selection in the Plasmodium falciparum population in northern Uganda (Tajima's D = -1.83205; Fu and Li's D = -1.82458). Polymorphism in the K13-propeller gene previously reported in Cambodia has been found in the Ugandan Plasmodium falciparum parasites. There is need for continuous surveillance for artemisinin resistance gene markers in the country.

A DNA fingerprinting procedure for ultra high-throughput genetic analysis of insects.

PubMed

Schlipalius, D I; Waldron, J; Carroll, B J; Collins, P J; Ebert, P R

2001-12-01

Existing procedures for the generation of polymorphic DNA markers are not optimal for insect studies in which the organisms are often tiny and background molecular information is often non-existent. We have used a new high throughput DNA marker generation protocol called randomly amplified DNA fingerprints (RAF) to analyse the genetic variability in three separate strains of the stored grain pest, Rhyzopertha dominica. This protocol is quick, robust and reliable even though it requires minimal sample preparation, minute amounts of DNA and no prior molecular analysis of the organism. Arbitrarily selected oligonucleotide primers routinely produced approximately 50 scoreable polymorphic DNA markers, between individuals of three independent field isolates of R. dominica. Multivariate cluster analysis using forty-nine arbitrarily selected polymorphisms generated from a single primer reliably separated individuals into three clades corresponding to their geographical origin. The resulting clades were quite distinct, with an average genetic difference of 37.5 +/- 6.0% between clades and of 21.0 +/- 7.1% between individuals within clades. As a prelude to future gene mapping efforts, we have also assessed the performance of RAF under conditions commonly used in gene mapping. In this analysis, fingerprints from pooled DNA samples accurately and reproducibly reflected RAF profiles obtained from individual DNA samples that had been combined to create the bulked samples.

Isolation of a complementary DNA clone for the human complement protein C2 and its use in the identification of a restriction fragment length polymorphism.

PubMed Central

Woods, D E; Edge, M D; Colten, H R

1984-01-01

Complementary DNA (cDNA) clones corresponding to the major histocompatibility (MHC) class III antigen, complement protein C2, have been isolated from human liver cDNA libraries with the use of a complex mixture of synthetic oligonucleotides (17 mer) that contains 576 different oligonucleotide sequences. The C2 cDNA were used to identify a DNA restriction enzyme fragment length polymorphism that provides a genetic marker within the MHC that was not detectable at the protein level. An extensive search for genomic polymorphisms using a cDNA clone for another MHC class III gene, factor B, failed to reveal any DNA variants. The genomic variants detected with the C2 cDNA probe provide an additional genetic marker for analysis of MHC-linked diseases. Images PMID:6086718

Genetic polymorphisms of genes involved in DNA repair and metabolism influence micronucleus frequencies in human peripheral blood lymphocytes.

PubMed

Dhillon, Varinderpal S; Thomas, Philip; Iarmarcovai, G; Kirsch-Volders, Micheline; Bonassi, Stefano; Fenech, Michael

2011-01-01

The cytokinesis-block micronucleus cytome (CBMNCyt) assay is a widely used technique for measuring DNA damage in human populations. The formation of micronuclei (MN) in dividing cells can result from chromosome breakage due to unrepaired or mis-repaired DNA lesions or chromosome malsegregation due to mitotic malfunction. The sensitivity of the MN assay to polymorphisms in various genes involved in DNA repair, activation/deactivation of carcinogens/chemicals/drugs/alcohol, folate metabolism pathway and micronutrient transport has been extensively reported in the literature. MN frequency is also an important index for determining DNA repair efficiency phenotype (including mis-repair), response to environmental exposure and identifying various dietary factors required for optimal genome stability. The aim of the present study is to review the reported in vivo associations between genotype and MN frequency in humans taking into considerations the presence of interactions with nutrients levels and/or exposure to genotoxins. One hundred and eleven publications linking MN frequency in peripheral blood lymphocytes to gene polymorphism were retrieved from PubMed. After applying exclusion criteria, only 37 studies were evaluated in the present review. Polymorphisms in XRCC1 (Arg280His), ERCC2 (Lys751Gln), CYP2E1 (c1/c2) and MTR (A2756G) were consistently associated with the MN formation. These results contribute substantial evidence to the hypothesis that genotype may influence MN frequency in human cells.

DNA methylation polymorphism in flue-cured tobacco and candidate markers for tobacco mosaic virus resistance*

PubMed Central

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

[Analysis on genetic polymorphism of 5 STR loci selected from X chromosome].

PubMed

Liu, Qi-ji; Gong, Yao-qin; Zhang, Xi-yu; Gao, Gui-min; Li, Jiang-xia; Guo, Yi-shou

2005-02-01

To select short tandem repeats(STR) from X chromosome. STR is a universal genetic marker that has changeable polymorphism and stable heredity in human genome. It is a specific DNA segment composed of 2-6 base pairs as its core sequence. It is an ideal DNA marker used in linkage analysis and gene mapping. In this study, 8 short tandem repeats were selected from two genomic clones on X chromosome by using BCM Search Launcher. Primers amplifying the STR loci were designed by using Primer 3.0 according to the unique sequence flanking the STRs. Polymorphisms of the short tandem repeats in Chinese population were evaluated by PCR amplification and PAGE. Five of these STRs were polymorphic. Chi-square test indicated that the distribution of genotypes agreed with Hardy-Weinberg equilibrium (P>0.05). Five polymorphic short tandem repeats have been identified on chromosome X and will be useful for linkage analysis and gene mapping.

DD genotype of ace gene I/D polymorphism is associated in a Turkish study population with osteoarthritis.

PubMed

Bayram, Banu; Sayın, Emrah; Güneş, Hasan Veysi; Değirmenci, Irfan; Türkoğlu, Züleyha; Doganer, Fulya; Coşan, Didem Turgut

2011-03-01

This study was conducted in Turkish osteoarthritis patients to determine the frequency of I/D polymorphism genotypes of angiotensin converting enzyme gene, and to examine the role of this polymorphism in osteoarthritis development. Genomic DNA obtained from 200 persons (135 patients with osteoarthritis and 65 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using I and D allele-specific primers. Polymerase chain reaction products were assessed with CCD camera by being exposed to 2% agarose gel electrophoresis. There was statistically significant difference between the groups with respect to genotype distribution (P < 0.001). The D allele frequency was indicated as 69% and I allele was as 31% in the patients, whereas it was 55-45% in the control group. Consequently, in this study, we may assert that ACE gene I/D polymorphism DD genotype determination is significant criteria for identifying patients who are likely to develop osteoarthritis in east population of Turkey.

A Genetic Linkage Map of Longleaf Pine (Pinus palustris Mill.) Based on Random Amplified Polymorphic DNAs

Treesearch

C.D. Nelson; Thomas L. Kubisiak; M. Stine; W.L. Nance

1994-01-01

Eight megagametophyte DNA samples from a single longleaf pine (Pinus palustris Mill.) tree were used to screen 576 oligonucleotide primers for random amplified polymorphic DNA (RAPD) fragments. Primers amplifying repeatable polymorphic fragments were further characterized within a sample of 72 megagametophytes from the same tree. Fragments...

Long interspersed repeated DNA (LINE) causes polymorphism at the rat insulin 1 locus.

PubMed

Lakshmikumaran, M S; D'Ambrosio, E; Laimins, L A; Lin, D T; Furano, A V

1985-09-01

The insulin 1, but not the insulin 2, locus is polymorphic (i.e., exhibits allelic variation) in rats. Restriction enzyme analysis and hybridization studies showed that the polymorphic region is 2.2 kilobases upstream of the insulin 1 coding region and is due to the presence or absence of an approximately 2.7-kilobase repeated DNA element. DNA sequence determination showed that this DNA element is a member of a long interspersed repeated DNA family (LINE) that is highly repeated (greater than 50,000 copies) and highly transcribed in the rat. Although the presence or absence of LINE sequences at the insulin 1 locus occurs in both the homozygous and heterozygous states, LINE-containing insulin 1 alleles are more prevalent in the rat population than are alleles without LINEs. Restriction enzyme analysis of the LINE-containing alleles indicated that at least two versions of the LINE sequence may be present at the insulin 1 locus in different rats. Either repeated transposition of LINE sequences or gene conversion between the resident insulin 1 LINE and other sequences in the genome are possible explanations for this.

Molecular evolution of the leptin exon 3 in some species of the family Canidae

PubMed Central

Chmurzynska, Agata; Zajac, Magdalena; Switonski, Marek

2003-01-01

The structure of the leptin gene seems to be well conserved. The polymorphism of this gene in four species belonging to the Canidae family (the dog (Canis familiaris) – 16 different breeds, the Chinese racoon dog (Nyctereutes procyonoides procyonoides), the red fox (Vulpes vulpes) and the arctic fox (Alopex lagopus)) were studied with the use of single strand conformation polymorphism (SSCP), restriction fragment length polymorphism (RFLP) and DNA sequencing techniques. For exon 2, all species presented the same SSCP pattern, while in exon 3 some differences were found. DNA sequencing of exon 3 revealed the presence of six nucleotide substitutions, differentiating the studied species. Three of them cause amino acid substitutions as well. For all dog breeds studied, SSCP patterns were identical. PMID:12939206

[Polymorphic loci and polymorphism analysis of short tandem repeats within XNP gene].

PubMed

Liu, Qi-Ji; Gong, Yao-Qin; Guo, Chen-Hong; Chen, Bing-Xi; Li, Jiang-Xia; Guo, Yi-Shou

2002-01-01

To select polymorphic short tandem repeat markers within X-linked nuclear protein (XNP) gene, genomic clones which contain XNP gene were recognized by homologous analysis with XNP cDNA. By comparing the cDNA with genomic DNA, non-exonic sequences were identified, and short tandem repeats were selected from non-exonic sequences by using BCM search Launcher. Polymorphisms of the short tandem repeats in Chinese population were evaluated by PCR amplification and PAGE. Five short tandem repeats were identified from XNP gene, two of which were polymorphic. Four and 11 alleles were observed in Chinese population for XNPSTR1 and XNPSTR4, respectively. Heterozygosities were 47% for XNPSTR1 and 70% for XNPSTR4. XNPSTR1 and XNPSTR4 localized within 3' end and intron 10, respectively. Two polymorphic short tandem repeats have been identified within XNP gene and will be useful for linkage analysis and gene diagnosis of XNP gene.

Mitochondrial DNA polymorphisms associated with longevity in a Finnish population.

PubMed

Niemi, Anna-Kaisa; Hervonen, Antti; Hurme, Mikko; Karhunen, Pekka J; Jylhä, Marja; Majamaa, Kari

2003-01-01

Sequence variation in mitochondrial DNA (mtDNA) may cause slight differences both in the functioning of the respiratory chain and in free radical production, and an association between certain mtDNA haplogroups and longevity has been suggested. In order to determine further the role of mtDNA in longevity, we studied the frequencies of mtDNA haplogroups and haplogroup clusters among elderly subjects and controls in a Finnish population. Samples were obtained from 225 persons aged 90-91 years (Vitality 90+) and from 400 middle-aged controls and 257 infants. MtDNA haplogroups were determined by restriction fragment length polymorphism. The haplogroup frequencies of the Vitality 90+ group differed from both those of the middle-aged controls ( P=0.01) and the infants ( P=0.00005), haplogroup H being less frequent than among the middle-aged subjects ( P=0.001) and infants ( P=0.00001), whereas haplogroups U and J were more frequent. Haplogroup clusters also differed between Vitality 90+ and both the middle-aged subjects ( P=0.002) and infants ( P=0.00001), the frequency of haplogroup cluster HV being lower in the former and that of UK and WIX being higher. These data suggest an association between certain mtDNA haplogroups or haplogroup clusters and longevity. Furthermore, our data appear to favour the presence of advantageous polymorphisms and support a role for mitochondria and mtDNA in the degenerative processes involved in ageing.

Genotyping of Single Nucleotide Polymorphisms in DNA Isolated from Serum Using Sequenom MassARRAY Technology.

PubMed

Clendenen, Tess V; Rendleman, Justin; Ge, Wenzhen; Koenig, Karen L; Wirgin, Isaac; Currie, Diane; Shore, Roy E; Kirchhoff, Tomas; Zeleniuch-Jacquotte, Anne

2015-01-01

Large epidemiologic studies have the potential to make valuable contributions to the assessment of gene-environment interactions because they prospectively collected detailed exposure data. Some of these studies, however, have only serum or plasma samples as a low quantity source of DNA. We examined whether DNA isolated from serum can be used to reliably and accurately genotype single nucleotide polymorphisms (SNPs) using Sequenom multiplex SNP genotyping technology. We genotyped 81 SNPs using samples from 158 participants in the NYU Women's Health Study. Each participant had DNA from serum and at least one paired DNA sample isolated from a high quality source of DNA, i.e. clots and/or cell precipitates, for comparison. We observed that 60 of the 81 SNPs (74%) had high call frequencies (≥95%) using DNA from serum, only slightly lower than the 85% of SNPs with high call frequencies in DNA from clots or cell precipitates. Of the 57 SNPs with high call frequencies for serum, clot, and cell precipitate DNA, 54 (95%) had highly concordant (>98%) genotype calls across all three sample types. High purity was not a critical factor to successful genotyping. Our results suggest that this multiplex SNP genotyping method can be used reliably on DNA from serum in large-scale epidemiologic studies.

Demonstration of Protein-Based Human Identification Using the Hair Shaft Proteome

PubMed Central

Leppert, Tami; Anex, Deon S.; Hilmer, Jonathan K.; Matsunami, Nori; Baird, Lisa; Stevens, Jeffery; Parsawar, Krishna; Durbin-Johnson, Blythe P.; Rocke, David M.; Nelson, Chad; Fairbanks, Daniel J.; Wilson, Andrew S.; Rice, Robert H.; Woodward, Scott R.; Bothner, Brian; Hart, Bradley R.; Leppert, Mark

2016-01-01

Human identification from biological material is largely dependent on the ability to characterize genetic polymorphisms in DNA. Unfortunately, DNA can degrade in the environment, sometimes below the level at which it can be amplified by PCR. Protein however is chemically more robust than DNA and can persist for longer periods. Protein also contains genetic variation in the form of single amino acid polymorphisms. These can be used to infer the status of non-synonymous single nucleotide polymorphism alleles. To demonstrate this, we used mass spectrometry-based shotgun proteomics to characterize hair shaft proteins in 66 European-American subjects. A total of 596 single nucleotide polymorphism alleles were correctly imputed in 32 loci from 22 genes of subjects’ DNA and directly validated using Sanger sequencing. Estimates of the probability of resulting individual non-synonymous single nucleotide polymorphism allelic profiles in the European population, using the product rule, resulted in a maximum power of discrimination of 1 in 12,500. Imputed non-synonymous single nucleotide polymorphism profiles from European–American subjects were considerably less frequent in the African population (maximum likelihood ratio = 11,000). The converse was true for hair shafts collected from an additional 10 subjects with African ancestry, where some profiles were more frequent in the African population. Genetically variant peptides were also identified in hair shaft datasets from six archaeological skeletal remains (up to 260 years old). This study demonstrates that quantifiable measures of identity discrimination and biogeographic background can be obtained from detecting genetically variant peptides in hair shaft protein, including hair from bioarchaeological contexts. PMID:27603779

Effects of physical exercise training in DNA damage and repair activity in humans with different genetic polymorphisms of hOGG1 (Ser326Cys).

PubMed

Soares, Jorge Pinto; Silva, Ana Inês; Silva, Amélia M; Almeida, Vanessa; Teixeira, João Paulo; Matos, Manuela; Gaivão, Isabel; Mota, Maria Paula

2015-12-01

The main purpose of this pilot study was to investigate the possible influence of genetic polymorphisms of the hOGG1 (Ser326Cys) gene in DNA damage and repair activity by 8-oxoguanine DNA glycosylase 1 (OGG1 enzyme) in response to 16 weeks of combined physical exercise training. Thirty-two healthy Caucasian men (40-74 years old) were enrolled in this study. All the subjects were submitted to a training of 16 weeks of combined physical exercise. The subjects with Ser/Ser genotype were considered as wild-type group (WTG), and Ser/Cys and Cys/Cys genotype were analysed together as mutant group (MG). We used comet assay in conjunction with formamidopyrimidine DNA glycoslyase (FPG) to analyse both strand breaks and FPG-sensitive sites. DNA repair activity were also analysed with the comet assay technique. Our results showed no differences between DNA damage (both strand breaks and FPG-sensitive sites) and repair activity (OGG1) between genotype groups (in the pre-training condition). Regarding the possible influence of genotype in the response to 16 weeks of physical exercise training, the results revealed a decrease in DNA strand breaks in both groups, a decrease in FPG-sensitive sites and an increase in total antioxidant capacity in the WTG, but no changes were found in MG. No significant changes in DNA repair activity was observed in both genotype groups with physical exercise training. This preliminary study suggests the possibility of different responses in DNA damage to the physical exercise training, considering the hOGG1 Ser326Cys polymorphism. Copyright © 2015 John Wiley & Sons, Ltd.

Role of genetic polymorphisms of CYP1A1, CYP3A5, CYP2C9, CYP2D6, and PON1 in the modulation of DNA damage in workers occupationally exposed to organophosphate pesticides.

PubMed

Singh, Satyender; Kumar, Vivek; Vashisht, Kapil; Singh, Priyanka; Banerjee, Basu Dev; Rautela, Rajender Singh; Grover, Shyam Sunder; Rawat, Devendra Singh; Pasha, Syed Tazeen; Jain, Sudhir Kumar; Rai, Arvind

2011-11-15

Organophosphate pesticides (OPs) are primarily metabolized by several xenobiotic metabolizing enzymes (XMEs). Very few studies have explored genetic polymorphisms of XMEs and their association with DNA damage in pesticide-exposed workers. The present study was designed to determine the role of genetic polymorphisms of CYP1A1, CYP3A5, CYP2C9, CYP2D6, and PON1 in the modulation of DNA damage in workers occupationally exposed to OPs. We examined 284 subjects including 150 workers occupationally exposed to OPs and 134 normal healthy controls. The DNA damage was evaluated using the alkaline comet assay and genotyping was done using PCR-RFLP. The results revealed that the PONase activity toward paraoxonase and AChE activity was found significantly lowered in workers as compared to control subjects (p<0.001). Workers showed significantly higher DNA damage compared to control subjects (14.37±2.15 vs. 6.24±1.37 tail% DNA, p<0.001). Further, the workers with CYP2D6*3PM and PON1 (QQ and MM) genotypes were found to have significantly higher DNA damage when compared to other genotypes (p<0.05). In addition, significant increase in DNA damage was also observed in workers with concomitant presence of certain CYP2D6 and PON1 (Q192R and L55M) genotypes which need further extensive studies. In conclusion, the results indicate that the PON1 and CYP2D6 genotypes can modulate DNA damage elicited by some OPs possibly through gene-environment interactions. Copyright © 2011 Elsevier Inc. All rights reserved.

4P: fast computing of population genetics statistics from large DNA polymorphism panels

PubMed Central

Benazzo, Andrea; Panziera, Alex; Bertorelle, Giorgio

2015-01-01

Massive DNA sequencing has significantly increased the amount of data available for population genetics and molecular ecology studies. However, the parallel computation of simple statistics within and between populations from large panels of polymorphic sites is not yet available, making the exploratory analyses of a set or subset of data a very laborious task. Here, we present 4P (parallel processing of polymorphism panels), a stand-alone software program for the rapid computation of genetic variation statistics (including the joint frequency spectrum) from millions of DNA variants in multiple individuals and multiple populations. It handles a standard input file format commonly used to store DNA variation from empirical or simulation experiments. The computational performance of 4P was evaluated using large SNP (single nucleotide polymorphism) datasets from human genomes or obtained by simulations. 4P was faster or much faster than other comparable programs, and the impact of parallel computing using multicore computers or servers was evident. 4P is a useful tool for biologists who need a simple and rapid computer program to run exploratory population genetics analyses in large panels of genomic data. It is also particularly suitable to analyze multiple data sets produced in simulation studies. Unix, Windows, and MacOs versions are provided, as well as the source code for easier pipeline implementations. PMID:25628874

DNA repair variants and breast cancer risk.

PubMed

Grundy, Anne; Richardson, Harriet; Schuetz, Johanna M; Burstyn, Igor; Spinelli, John J; Brooks-Wilson, Angela; Aronson, Kristan J

2016-05-01

A functional DNA repair system has been identified as important in the prevention of tumour development. Previous studies have hypothesized that common polymorphisms in DNA repair genes could play a role in breast cancer risk and also identified the potential for interactions between these polymorphisms and established breast cancer risk factors such as physical activity. Associations with breast cancer risk for 99 single nucleotide polymorphisms (SNPs) from genes in ten DNA repair pathways were examined in a case-control study including both Europeans (644 cases, 809 controls) and East Asians (299 cases, 160 controls). Odds ratios in both additive and dominant genetic models were calculated separately for participants of European and East Asian ancestry using multivariate logistic regression. The impact of multiple comparisons was assessed by correcting for the false discovery rate within each DNA repair pathway. Interactions between several breast cancer risk factors and DNA repair SNPs were also evaluated. One SNP (rs3213282) in the gene XRCC1 was associated with an increased risk of breast cancer in the dominant model of inheritance following adjustment for the false discovery rate (P < 0.05), although no associations were observed for other DNA repair SNPs. Interactions of six SNPs in multiple DNA repair pathways with physical activity were evident prior to correction for FDR, following which there was support for only one of the interaction terms (P < 0.05). No consistent associations between variants in DNA repair genes and breast cancer risk or their modification by breast cancer risk factors were observed. © 2016 Wiley Periodicals, Inc.

Methylenetetrahydrofolate reductase gene polymorphisms and risk of acute lymphoblastic leukemia in children.

PubMed

Sadananda Adiga, M N; Chandy, S; Ramachandra, N; Appaji, L; Aruna Kumari, B S; Ramaswamy, G; Savithri, H S; Krishnamoorthy, L

2010-01-01

Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and is involved in DNA synthesis, DNA repair and DNA methylation. Genetic polymorphisms of this enzyme have been shown to impact several diseases, including cancer. Leukemias are malignancies arising from rapidly proliferating hematopoietic cells having great requirement of DNA synthesis. This case-control study was undertaken to analyze the association of the MTHFR gene polymorphisms 677 C"T and 1298 A"C and the risk of acute lymphoblastic leukemia in children. Eighty-six patients aged below 15 years with a confirmed diagnosis of acute lymphoblastic leukemia (ALL) and 99 matched controls were taken for this study. Analysis of the polymorphisms was done using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Frequency of MTHFR 677 CC and CT were 85.9% and 14.1% in the controls, and 84.9% and 15.1% in the cases. The 'T' allele frequency was 7% and 7.5% in cases and controls respectively. The frequency of MTHFR 1298 AA, AC, and CC were 28.3%, 55.6% and 16.1% for controls and 23.3%, 59.3% and 17.4% for cases respectively. The 'C' allele frequency for 1298 A-->C was 43.9% and 47% respectively for controls and cases. The odds ratio (OR) for C677T was 1.08 (95% CI 0.48-2.45, p = 0.851) and OR for A1298C was 1.29 (95% CI 0.65-2.29, p = 0.46) and OR for 1298 CC was 1.31 (95% CI 0.53-3.26, p = 0.56). The OR for the combined heterozygous status (677 CT and 1298 AC) was 1.94 (95% CI 0.58-6.52, p = 0.286). The prevalence of 'T' allele for 677 MTHFR polymorphism was low in the population studied. There was no association between MTHFR 677 C-->T and 1298 A-->C gene polymorphisms and risk of ALL, which may be due to the small sample size.

Primary DNA damage and genetic polymorphisms for CYP1A1, EPHX and GSTM1 in workers at a graphite electrode manufacturing plant

PubMed Central

Moretti, Massimo; Dell'Omo, Marco; Villarini, Milena; Pastorelli, Roberta; Muzi, Giacomo; Airoldi, Luisa; Pasquini, Rossana

2007-01-01

Background The results of a cross-sectional study aimed to evaluate whether genetic polymorphisms (biomarkers of susceptibility) for CYP1A1, EPHX and GSTM1 genes that affect polycyclic aromatic hydrocarbons (PAH) activation and detoxification might influence the extent of primary DNA damage (biomarker of biologically effective dose) in PAH exposed workers are presented. PAH-exposure of the study populations was assessed by determining the concentration of 1-hydroxypyrene (1OHP) in urine samples (biomarker of exposure dose). Methods The exposed group consisted of workers (n = 109) at a graphite electrode manufacturing plant, occupationally exposed to PAH. Urinary 1OHP was measured by HPLC. Primary DNA damage was evaluated by the alkaline comet assay in peripheral blood leukocytes. Genetic polymorphisms for CYP1A1, EPHX and GSTM1 were determined by PCR or PCR/RFLP analysis. Results 1OHP and primary DNA damage were significantly higher in electrode workers compared to reference subjects. Moreover, categorization of subjects as normal or outlier highlighted an increased genotoxic risk OR = 2.59 (CI95% 1.32–5.05) associated to exposure to PAH. Polymorphisms in EPHX exons 3 and 4 was associated to higher urinary concentrations of 1OHP, whereas none of the genotypes analyzed (CYP1A1, EPHX, and GSTM1) had any significant influence on primary DNA damage as evaluated by the comet assay. Conclusion The outcomes of the present study show that molecular epidemiology approaches (i.e. cross-sectional studies of genotoxicity biomarkers) can play a role in identifying common genetic risk factors, also attempting to associate the effects with measured exposure data. Moreover, categorization of subjects as normal or outlier allowed the evaluation of the association between occupational exposure to PAH and DNA damage highlighting an increased genotoxic risk. PMID:17908297

Chloroplast DNA haplotype variation and population differentiation in Sorbus aucuparia L. (Rosaceae: Maloideae).

PubMed

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.

Methylation of avpr1a in the cortex of wild prairie voles: effects of CpG position and polymorphism

PubMed Central

Maguire, S. M.; Phelps, S. M.

2017-01-01

DNA methylation can cause stable changes in neuronal gene expression, but we know little about its role in individual differences in the wild. In this study, we focus on the vasopressin 1a receptor (avpr1a), a gene extensively implicated in vertebrate social behaviour, and explore natural variation in DNA methylation, genetic polymorphism and neuronal gene expression among 30 wild prairie voles (Microtus ochrogaster). Examination of CpG density across 8 kb of the locus revealed two distinct CpG islands overlapping promoter and first exon, characterized by few CpG polymorphisms. We used a targeted bisulfite sequencing approach to measure DNA methylation across approximately 3 kb of avpr1a in the retrosplenial cortex, a brain region implicated in male space use and sexual fidelity. We find dramatic variation in methylation across the avrp1a locus, with pronounced diversity near the exon–intron boundary and in a genetically variable putative enhancer within the intron. Among our wild voles, differences in cortical avpr1a expression correlate with DNA methylation in this putative enhancer, but not with the methylation status of the promoter. We also find an unusually high number of polymorphic CpG sites (polyCpGs) in this focal enhancer. One polyCpG within this enhancer (polyCpG 2170) may drive variation in expression either by disrupting transcription factor binding motifs or by changing local DNA methylation and chromatin silencing. Our results contradict some assumptions made within behavioural epigenetics, but are remarkably concordant with genome-wide studies of gene regulation. PMID:28280564

DNA polymorphism in recombining and non-recombing mating-type-specific loci of the smut fungus Microbotryum

PubMed Central

Votintseva, A A; Filatov, D A

2011-01-01

The population-genetic processes leading to the genetic degeneration of non-recombining regions have mainly been studied in animal and plant sex chromosomes. Here, we report population genetic analysis of the processes in the non-recombining mating-type-specific regions of the smut fungus Microbotryum violaceum. M. violaceum has A1 and A2 mating types, determined by mating-type-specific ‘sex chromosomes' that contain 1–2 Mb long non-recombining regions. If genetic degeneration were occurring, then one would expect reduced DNA polymorphism in the non-recombining regions of this fungus. The analysis of DNA diversity among 19 M. violaceum strains, collected across Europe from Silene latifolia flowers, revealed that (i) DNA polymorphism is relatively low in all 20 studied loci (π∼0.15%), (ii) it is not significantly different between the two mating-type-specific chromosomes nor between the non-recombining and recombining regions, (iii) there is substantial population structure in M. violaceum populations, which resembles that of its host species, S. latifolia, and (iv) there is significant linkage disequilibrium, suggesting that widespread selfing in this species results in a reduction of the effective recombination rate across the genome. We hypothesise that selfing-related reduction of recombination across the M. violaceum genome negates the difference in the level of DNA polymorphism between the recombining and non-recombining regions, and may possibly lead to similar levels of genetic degeneration in the mating-type-specific regions of the non-recombining ‘sex chromosomes' and elsewhere in the genome. PMID:21081967

XPC genotypes/diplotypes play no independent or interaction role with PAH-DNA adducts for breast cancer risk

PubMed Central

Shen, Jing; Gammon, Marilie D.; Terry, Mary Beth; Teitelbaum, Susan L.; Eng, Sybil M.; Neugut, Alfred I.; Santella, Regina M.

2008-01-01

Xeroderma pigmentosum complementation group C (XPC) is an important DNA nuclear excision repair (NER) gene that recognizes the damage caused by variety of bulky DNA adducts. We evaluated the association of two common non-synonymous polymorphisms in XPC (Ala499Val and Lys939Gln) with breast cancer risk in the Long Island Breast Cancer Study Project (LIBCSP), a population-based case-control study. Genotyping of 1,067 cases and 1,110 controls was performed by a high throughput assay with fluorescence polarization. There were no overall associations between XPC polymorphisms and breast cancer risk. A diplotype CC-CC was significantly associated with increased breast cancer risk compared with diplotype CA-CA (OR = 1.4, 95%CI: 1.0–1.9), but was not significant when compared with all other diplotypes combined (OR = 1.22, 95%CI: 0.97–1.53). No modification effects were observed for XPC genotypes by cigarette smoking status, smoking pack years or polycyclic aromatic hydrocarbons (PAH) DNA adducts. The increase in breast cancer risk was slightly more pronounced among women with detectable PAH-DNA adducts and carrying the diplotype CC-CC (OR = 1.6, 95%CI: 1.1–2.2) compared to women with non detectable PAH-DNA adducts carrying other diplotypes combined, but no statistically significant interaction was observed (P interaction = 0.69). These data suggest that XPC have neither independent effects nor interactions with cigarette smoking and PAH-DNA adducts for breast cancer risk. Further studies with multiple genetic polymorphisms in NER pathway are warranted. PMID:18053706

Cigarette smoking and hOGG1 Ser326Cys polymorphism are associated with 8-OHdG accumulation on mitochondrial DNA in thoracic esophageal squamous cell carcinoma.

PubMed

Lin, Chen-Sung; Wang, Liang-Shun; Chou, Teh-Ying; Hsu, Wen-Hu; Lin, Hui-Chen; Lee, Shu-Yu; Lee, Mau-Hua; Chang, Shi-Chuan; Wei, Yau-Huei

2013-12-01

We examined whether cigarette smoking affects the degrees of oxidative damage (8-hydroxyl-2'-deoxyguanosine [8-OHdG]) on mitochondrial DNA (mtDNA), whether the degree of 8-OHdG accumulation on mtDNA is related to the increased total mtDNA copy number, and whether human 8-oxoguanine DNA glycosylase 1 (hOGG1) Ser326Cys polymorphisms affect the degrees of 8-OHdG accumulation on mtDNA in thoracic esophageal squamous cell carcinoma (TESCC). DNA extracted from microdissected tissues of paired noncancerous esophageal muscles, noncancerous esophageal mucosa, and cancerous TESCC nests (n = 74) along with metastatic lymph nodes (n = 38) of 74 TESCC patients was analyzed. Both the mtDNA copy number and mtDNA integrity were analyzed by quantitative real-time polymerase chain reaction (PCR). The hOGG1 Ser326Cys polymorphisms were identified by restriction fragment length polymorphism PCR and PCR-based direct sequencing. Among noncancerous esophageal mucosa, cancerous TESCC nests, and metastatic lymph nodes, the mtDNA integrity decreased (95.2 to 47.9 to 18.6 %; P < 0.001) and the mtDNA copy number disproportionally increased (0.163 to 0.204 to 0.207; P = 0.026). In TESCC, higher indexes of cigarette smoking (0, 0-20, 20-40, and >40 pack-years) were related to an advanced pathologic N category (P = 0.038), elevated mtDNA copy number (P = 0.013), higher mtDNA copy ratio (P = 0.028), and increased mtDNA integrity (P = 0.069). The TESCC mtDNA integrity in patients with Ser/Ser, Ser/Cys, and Cys/Cys hOGG1 variants decreased stepwise from 65.2 to 52.1 to 41.3 % (P = 0.051). Elevated 8-OHdG accumulations on mtDNA in TESCC were observed. Such accumulations were associated with a compensatory increase in total mtDNA copy number, indexes of cigarette smoking, and hOGG1 Ser326Cys polymorphisms.

Mitochondrial DNA polymorphism among populations of Melipona quadrifasciata quadrifasciata Lepeletier (Apidae: Meliponini) from southern Brazil.

PubMed

Torres, Rogelio R; Arias, Maria C; Moretto, Geraldo

2009-01-01

The geographical distribution of the Brazilian endemic stingless bee Melipona quadrifasciata quadrifasciata Lepeletier ranges from Rio Grande do Sul to Minas Gerais states. The objective of the present study was to verify mtDNA polymorphisms among samples of M. q. quadrifasciata collected in southern Brazil. Twenty nine colonies from three localities (Blumenau and Mafra/SC and Prudentópolis/ PR) were sampled. Seven mtDNA regions were amplified and further digested with 15 restriction enzymes (PCR-RFLP). Five composite haplotypes were identified, with two unique to samples from Prudentópolis and the remaining three to samples from Mafra and/or Blumenau.

The Joint Effects of Body Mass Index and MAOA Gene Polymorphism on Depressive Symptoms.

PubMed

Liu, Yangyang

2015-07-01

The objective of the present study was to examine the joint effects of the body mass index and the MAOA gene polymorphism on depressive symptoms. In two independent Chinese samples, we measured adolescents' depressive symptoms and body mass index and collected their DNA. The results indicated that the main effects of the MAOA gene polymorphism on depressive symptoms were significant. However, the main effects of body mass index and the interaction of the MAOA gene polymorphism and body mass index on depressive symptoms were not significant. By using Chinese adolescents, this study confirmed that the MAOA gene polymorphism directly influenced adolescents' depressive symptoms.

Assay for identification of heterozygous single-nucleotide polymorphism (Ala67Thr) in human poliovirus receptor gene.

PubMed

Nandi, Shyam Sundar; Sharma, Deepa Kailash; Deshpande, Jagadish M

2016-07-01

It is important to understand the role of cell surface receptors in susceptibility to infectious diseases. CD155 a member of the immunoglobulin super family, serves as the poliovirus receptor (PVR). Heterozygous (Ala67Thr) polymorphism in CD155 has been suggested as a risk factor for paralytic outcome of poliovirus infection. The present study pertains to the development of a screening test to detect the single nucleotide (SNP) polymorphism in the CD155 gene. New primers were designed for PCR, sequencing and SNP analysis of Exon2 of CD155 gene. DNAs extracted from either whole blood (n=75) or cells from oral cavity (n=75) were used for standardization and validation of the SNP assay. DNA sequencing was used as the gold standard method. A new SNP assay for detection of heterozygous Ala67Thr genotype was developed and validated by testing 150 DNA samples. Heterozygous CD155 was detected in 27.33 per cent (41/150) of DNA samples tested by both SNP detection assay and sequencing. The SNP detection assay was successfully developed for identification of Ala67Thr polymorphism in human PVR/CD155 gene. The SNP assay will be useful for large scale screening of DNA samples.

Genetic variation in a DNA double strand break repair gene in saudi population: a comparative study with worldwide ethnic groups.

PubMed

Areeshi, Mohammed Yahya

2013-01-01

DNA repair capacity is crucial in maintaining cellular functions and homeostasis. However, it can be altered based on DNA sequence variations in DNA repair genes and this may lead to the development of many diseases including malignancies. Identification of genetic polymorphisms responsible for reduced DNA repair capacity is necessary for better prevention. Homologous recombination (HR), a major double strand break repair pathway, plays a critical role in maintaining the genome stability. The present study was performed to determine the frequency of the HR gene XRCC3 Exon 7 (C18067T, rs861539) polymorphisms in Saudi Arabian population in comparison with epidemiological studies by "MEDLINE" search to equate with global populations. The variant allelic (T) frequency of XRCC3 (C>T) was found to be 39%. Our results suggest that frequency of XRCC3 (C>T) DNA repair gene exhibits distinctive patterns compared with the Saudi Arabian population and this might be attributed to ethnic variation. The present findings may help in high-risk screening of humans exposed to environmental carcinogens and cancer predisposition in different ethnic groups.

Genetic polymorphisms of 54 mitochondrial DNA SNP loci in Chinese Xibe ethnic minority group

PubMed Central

Shen, Chun-Mei; Hu, Li; Yang, Chun-Hua; Yin, Cai-Yong; Li, Zhi-Dan; Meng, Hao-Tian; Guo, Yu-Xin; Mei, Ting; Chen, Feng; Zhu, Bo-Feng

2017-01-01

We analyzed the genetic polymorphisms of 54 mitochondrial DNA (mtDNA) variants in Chinese Xibe ethnic minority group. A total of 137 unrelated healthy volunteers from Chinese Xibe group were the objects of our study. Among the selected loci, there were 51 variable positions including transitions and transversions, and single nucleotide transitions were common (83.93%) versus transversions. These variations defined 64 different mtDNA haplotypes exclusive of (CA)n and 9 bp deletion variation. The haplotype diversity and discrimination power in Xibe population were 0.9800 ± 0.004 and 0.9699, respectively. Besides, we compared Xibe group with 18 other populations and reconstructed a phylogenetic tree using Neighbor-Joining method. The result revealed that Xibe group was a close to Xinjiang Han and Yanbian Korean groups. Our data also indicated that Xibe group has a close relationship with Daur and Ewenki groups, which is reflected by the history that Xibe was influenced by Daur and Ewenki groups during the development of these groups. In conclusion, the variants we studied are polymorphic and could be used as informative genetic markers for forensic and population genetic application. PMID:28327596

Length polymorphism scanning is an efficient approach for revealing chloroplast DNA variation.

Treesearch

Matthew E. Horning; Richard C. Cronn

2006-01-01

Phylogeographic and population genetic screens of chloroplast DNA (cpDNA) provide insights into seedbased gene flow in angiosperms, yet studies are frequently hampered by the low mutation rate of this genome. Detection methods for intraspecific variation can be either direct (DNA sequencing) or indirect (PCR-RFLP), although no single method incorporates the best...

Polymorphism of the ACE gene and the risk of obstructive sleep apnoea.

PubMed

Chmielewska, Izabela; Mlak, Radosław; Krawczyk, Paweł; Czukiewska, Ewa; Milanowski, Janusz

2013-01-01

Obstructive sleep apnoea/hypopnea syndrome (OSA) is characterized by obstruction of the upper airway during sleep, resulting in repetitive breathing pauses accompanied by oxygen desaturation and arousal from sleep. Among the candidate genes affecting the risk of OSA, genes whose polymorphisms influence the development of diseases with similar pathogenesis such as OSA could be listed: APOE, genes for leptin and leptin receptor, TNFA1, ADRB2 and ACE (gene for angiotensin-converting enzyme). Until now there has been a confirmed relationship between ACE gene polymorphism and cardiovascular diseases, but its effect on the incidence of OSA is debatable. The aim of this study was to investigate the effect of ACE gene insertion/deletion (I/D) polymorphism on the risk of OSA. Fifty-five patients with confirmed diagnose of OSA and qualified to CPAP therapy entered the study. The control group included 50 subjects who did not complain of any sleep related symptoms. Diagnose of OSA was set on the basis of full overnight polysomnography together with Epworth Sleepiness Scale according to American Academy of Sleep Medicine guidelines. DNA was isolated from peripheral blood leukocytes with Qiagen DNA mini Kit. ACE gene polymorphism was determined in genomic DNA using allele specific polymerase chain reaction. Different sizes of PCR products were observed on agarose gel electrophoresis. There were non-significant differences in the frequency of ACE genotypes. However, allele D had significantly lower prevalence in the study group than in the control group. (χ(2) = 4.25 p = 0.04). Moreover, I allele carriers had a threefold greater risk of developing OSA (HR = 2.748, 95% CI = 1.029-7.340, p < 0.05). Analysis of ACE gene polymorphism might be useful to determine the risk of developing OSA in clinically predisposed patients.

Lack of association between ESR1 gene polymorphisms and premature ovarian failure in Serbian women.

PubMed

Li, J; Vujovic, S; Dalgleish, R; Thompson, J; Dragojevic-Dikic, S; Al-Azzawi, F

2014-06-01

It has previously been reported that estrogen receptor-alpha (ERα) gene (ESR1: estrogen receptor 1) polymorphisms are associated with premature ovarian failure (POF). The aim of this study was to investigate whether these genetic polymorphisms of ESR1 are associated with POF in Serbian women. A series of 197 POF cases matched with 547 fertile controls was recruited by the Institute for Endocrinology, Diabetes and Metabolic Disorders of Serbia between 2007 and 2010. Genomic DNA was extracted from saliva using Oragene® DNA sample collection kits. Two single-nucleotide polymorphisms (SNPs), PvuII and XbaI, in ESR1 were genotyped by dynamic allele-specific hybridization. Haplotype analyses were performed with the restriction fragment length polymorphism method. SNP and haplotype effects were analyzed by logistic regression models. No significant difference was found in the distribution of ESR1 PvuII and XbaI polymorphisms or haplotypes between the POF and control groups. The two ESR1 SNPs, PvuII and XbaI, are not commonly associated with POF in Serbian women and may not contribute to the genetic basis of the condition.

[Association of muscle segment homeobox gene 1 polymorphisms with nonsyndromic cleft lip with or without cleft palate].

PubMed

Zhang, Li; Tang, Jun-Ling; Liang, Shang-Zheng

2008-06-01

Muscle segment homeobox gene (MSX)1 has been proposed as a gene in which mutations may contribute to nonsyndromic cleft lip with or without cleft palate (NSCL/P). To study MSX1 polymorphisms in NSCL/ P by means of polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP), and investigate the association of MSX1 exons 1 polymorphisms with NSCL/P. DNA were extracted from blood samples from NSCL/P and unrelated normal subjects. Genome DNA from peripheral leukocyte with these blood samples were extracted, which was used as template to amplify desired gene fragment of MSX1 exons 1 by means of polymerase chain reaction (PCR). The PCR products were examined by single-strand conformation polymorphism (SSCP). The MSX1 exons 1 polymorphisms were examined by sequencing if mutations were found. MSX1 genes of exon 1 mutation was not been found in the NSCL/P and unrelated normal subjects by SSCP. No correlation between MSX1 exon 1 and NSCL/P was found. MSX1 exon 1 may not be a key gene (susceptibility gene) in NSCL/P.

Skin score correlates with global DNA methylation and GSTO1 A140D polymorphism in arsenic-affected population of Eastern India.

PubMed

Majumder, Moumita; Dasgupta, Uma B; Guha Mazumder, D N; Das, Nilansu

2017-07-01

Arsenic is a potent environmental toxicant causing serious public health concerns in India, Bangladesh and other parts of the world. Gene- and promoter-specific hypermethylation has been reported in different arsenic-exposed cell lines, whereas whole genome DNA methylation study suggested genomic hypo- and hypermethylation after arsenic exposure in in vitro and in vivo studies. Along with other characteristic biomarkers, arsenic toxicity leads to typical skin lesions. The present study demonstrates significant correlation between severities of skin manifestations with their whole genome DNA methylation status as well as with a particular polymorphism (Ala 140 Asp) status in arsenic metabolizing enzyme Glutathione S-transferase Omega-1 (GSTO1) in arsenic-exposed population of the district of Nadia, West Bengal, India.

Variations in the Phytophthora infestans Population in Nepal as Revealed by Nuclear and Mitochondrial DNA Polymorphisms.

PubMed

Ghimire, S R; Hyde, K D; Hodgkiss, I J; Shaw, D S; Liew, E C Y

2003-02-01

ABSTRACT Phytophthora infestans isolates collected from potato and tomato crops from various parts of Nepal during the 1999 and 2000 crop seasons were characterized for nuclear and mitochondrial DNA polymorphisms using restriction fragment length polymorphism markers. The nuclear DNA probe RG57 detected 11 multilocus genotypes among 280 isolates. Three genotypes were detected 21 times or more, constituting 94% of the total population, whereas frequencies of other genotypes ranged from 0.004 to 0.014. The overall genotypic diversity as estimated by the Gleason index was 1.78. Most of the overall diversity was present at the highest level (i.e., interregional, 46%), indicating limited gene flow among regions. Cluster analysis of multilocus genotypes derived from RG57 and mating type data for Nepalese isolates and representative isolates worldwide showed Nepalese isolates grouping into four clusters. Characterization of 67 isolates for mitochondrial DNA polymorphisms revealed the presence of two mt-haplotypes, Ia and Ib with the proportions of 0.88 and 0.12, respectively. Polymorphisms in nuclear and mitochondrial DNA revealed a moderate level of diversity in this population. Genotype NP3 had an identical RG57 fingerprint to US1 and had mt-haplotype Ib, confirming the presence of an old population in Nepal. Most of the genotypes had a different RG57 fingerprint than that of US1 and mt-haplotype Ia, the common characteristics of new populations. The presence of a new population at high proportions in Nepal was consistent with the global trend of mt-haplotype distribution, and suggests the displacement of old populations. This study indicates at least three possible introductions of P. infestans to Nepal.

Association of the hOGG1 Ser326Cys polymorphism with sporadic amyotrophic lateral sclerosis.

PubMed

Coppedè, Fabio; Mancuso, Michelangelo; Lo Gerfo, Annalisa; Carlesi, Cecilia; Piazza, Selina; Rocchi, Anna; Petrozzi, Lucia; Nesti, Claudia; Micheli, Dario; Bacci, Andrea; Migliore, Lucia; Murri, Luigi; Siciliano, Gabriele

2007-06-13

Amyotropic lateral sclerosis (ALS) is a fatal and progressive neurodegenerative disease causing the loss of motoneurons of the brain and the spinal cord. The etiology of ALS is still uncertain, but males are at increased risk for the disease than females. Several studies have suggested that motoneurons in ALS might be subjected to the double insult of increased DNA oxidative damage and deficiencies in DNA repair systems. Particularly, increased levels of 8-oxoguanine and impairments of the DNA base excision repair system have been observed in neurons of ALS patients. There is evidence that the Ser326Cys polymorphism of the human 8-oxoguanine DNA glycosylase 1 (hOGG1) gene is associated with a reduced DNA repair activity. To evaluate the role of the hOGG1 Ser326Cys polymorphism in sporadic ALS (sALS), we screened 136 patients and 129 matched controls. In the total population, we observed association between both the Cys326 allele (p=0.02) and the combined Ser326Cys+Cys326Cys genotype (OR=1.65, 95% CI=1.06-2.88) and increased risk of disease. After stratification by gender, the Cys326 allele (p=0.01), both the Ser326Cys genotype (OR=2.14, 95% CI=1.09-4.19) and the combined Ser326Cys+Cys326Cys genotype (OR=2.15, 95% CI=1.16-4.01) were associated with sALS risk only in males. No significant association between the Ser326Cys polymorphism and disease phenotype, including age and site of onset and disease progression, was observed. Present results suggest a possible involvement of the hOGG1 Ser326Cys polymorphism in sALS pathogenesis.

Data from complete mtDNA sequencing of Tunisian centenarians: testing haplogroup association and the "golden mean" to longevity.

PubMed

Costa, Marta D; Cherni, Lotfi; Fernandes, Verónica; Freitas, Fernando; Ammar El Gaaied, Amel Ben; Pereira, Luísa

2009-04-01

Since the mitochondrial theory of ageing was proposed, mitochondrial DNA (mtDNA) diversity has been largely studied in old people, however complete genomes are still rare, being limited to Japanese and UK/US samples. In this work, we evaluated possible longevity associated polymorphisms/haplogroups in an African population, from Tunisia, by performing complete mtDNA sequencing. This population has a mixed Eurasian/sub-Saharan mtDNA gene pool, which could potentially facilitate the evaluation of association for sub-Saharan lineages. Sub-Saharan haplogroups were shown to be significantly less represented in centenarians (9.5%) than in controls (54.5%), but it is not possible to rule out an influence of population structure, which is high in these populations. No recurrent polymorphism were more frequent in centenarians than in controls, and although the Tunisian centenarians presented less synonymous and replacement polymorphisms than controls, this difference was not statistically significant. So far, it does not seem that centenarians have significantly less mildly deleterious substitutions, not only in Tunisia but also in Japanese and UK/US samples, as tested here, not favouring a "golden mean" to longevity.

Long interspersed repeated DNA (LINE) causes polymorphism at the rat insulin 1 locus.

PubMed Central

Lakshmikumaran, M S; D'Ambrosio, E; Laimins, L A; Lin, D T; Furano, A V

1985-01-01

The insulin 1, but not the insulin 2, locus is polymorphic (i.e., exhibits allelic variation) in rats. Restriction enzyme analysis and hybridization studies showed that the polymorphic region is 2.2 kilobases upstream of the insulin 1 coding region and is due to the presence or absence of an approximately 2.7-kilobase repeated DNA element. DNA sequence determination showed that this DNA element is a member of a long interspersed repeated DNA family (LINE) that is highly repeated (greater than 50,000 copies) and highly transcribed in the rat. Although the presence or absence of LINE sequences at the insulin 1 locus occurs in both the homozygous and heterozygous states, LINE-containing insulin 1 alleles are more prevalent in the rat population than are alleles without LINEs. Restriction enzyme analysis of the LINE-containing alleles indicated that at least two versions of the LINE sequence may be present at the insulin 1 locus in different rats. Either repeated transposition of LINE sequences or gene conversion between the resident insulin 1 LINE and other sequences in the genome are possible explanations for this. Images PMID:3016521

Demonstration of protein-based human identification using the hair shaft proteome [Protein-based human identification: A proof of concept using the hair shaft proteome

DOE PAGES

Parker, Glendon J.; Leppert, Tami; Anex, Deon S.; ...

2016-09-07

Human identification from biological material is largely dependent on the ability to characterize genetic polymorphisms in DNA. Unfortunately, DNA can degrade in the environment, sometimes below the level at which it can be amplified by PCR. Protein however is chemically more robust than DNA and can persist for longer periods. Protein also contains genetic variation in the form of single amino acid polymorphisms. These can be used to infer the status of non-synonymous single nucleotide polymorphism alleles. To demonstrate this, we used mass spectrometry-based shotgun proteomics to characterize hair shaft proteins in 66 European-American subjects. A total of 596 singlemore » nucleotide polymorphism alleles were correctly imputed in 32 loci from 22 genes of subjects’ DNA and directly validated using Sanger sequencing. Estimates of the probability of resulting individual non-synonymous single nucleotide polymorphism allelic profiles in the European population, using the product rule, resulted in a maximum power of discrimination of 1 in 12,500. Imputed non-synonymous single nucleotide polymorphism profiles from European–American subjects were considerably less frequent in the African population (maximum likelihood ratio = 11,000). The converse was true for hair shafts collected from an additional 10 subjects with African ancestry, where some profiles were more frequent in the African population. Genetically variant peptides were also identified in hair shaft datasets from six archaeological skeletal remains (up to 260 years old). Furthermore, this study demonstrates that quantifiable measures of identity discrimination and biogeographic background can be obtained from detecting genetically variant peptides in hair shaft protein, including hair from bioarchaeological contexts.« less

Demonstration of protein-based human identification using the hair shaft proteome [Protein-based human identification: A proof of concept using the hair shaft proteome

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

Parker, Glendon J.; Leppert, Tami; Anex, Deon S.

Human identification from biological material is largely dependent on the ability to characterize genetic polymorphisms in DNA. Unfortunately, DNA can degrade in the environment, sometimes below the level at which it can be amplified by PCR. Protein however is chemically more robust than DNA and can persist for longer periods. Protein also contains genetic variation in the form of single amino acid polymorphisms. These can be used to infer the status of non-synonymous single nucleotide polymorphism alleles. To demonstrate this, we used mass spectrometry-based shotgun proteomics to characterize hair shaft proteins in 66 European-American subjects. A total of 596 singlemore » nucleotide polymorphism alleles were correctly imputed in 32 loci from 22 genes of subjects’ DNA and directly validated using Sanger sequencing. Estimates of the probability of resulting individual non-synonymous single nucleotide polymorphism allelic profiles in the European population, using the product rule, resulted in a maximum power of discrimination of 1 in 12,500. Imputed non-synonymous single nucleotide polymorphism profiles from European–American subjects were considerably less frequent in the African population (maximum likelihood ratio = 11,000). The converse was true for hair shafts collected from an additional 10 subjects with African ancestry, where some profiles were more frequent in the African population. Genetically variant peptides were also identified in hair shaft datasets from six archaeological skeletal remains (up to 260 years old). Furthermore, this study demonstrates that quantifiable measures of identity discrimination and biogeographic background can be obtained from detecting genetically variant peptides in hair shaft protein, including hair from bioarchaeological contexts.« less

Distribution of a length polymorphism 5{prime} to exon 1 of the antithrombin III (ATIII) gene in the Chinese

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

Low, P.S.; Liu, Y.; Saha, N.

A length polymorphism at the 5{prime} untranslated region of the ATIII gene has been described as having been detected by polymerase chain reaction (PCR) with a frequency of 0.75 for the short allele (S) in the Caucasian population. This length polymorphism of the ATIII gene has been studied in 251 Chinese healthy subjects. Genomic DNA was amplified by PCR with primers of published sequences. Fragments of the amplified DNA were separated by agarose gel electrophoresis (3% NuSieve and 1% Seakem GTG) and photographed on a UV transilluminator. The frequency of the short allele (S) was found to be significantly lowermore » (0.37) than that in the Caucasians (0.75). The distribution of genotypes of this polymorphism of the ATIII gene was at Hardy-Weinberg equilibrium. The large difference of allelic frequencies in the Mongoloid and Caucasian populations makes it a useful marker for population studies.« less

DNA damage and genetic methylation changes caused by Cd in Arabidopsis thaliana seedlings.

PubMed

Li, Zhaoling; Liu, Zhihong; Chen, Ruijuan; Li, Xiaojun; Tai, Peidong; Gong, Zongqiang; Jia, Chunyun; Liu, Wan

2015-09-01

Amplified fragment length polymorphism (AFLP) and methylation-sensitive amplification polymorphism (MASP) techniques are sensitive to deoxyribonucleic acid (DNA) damage and genetic methylation, respectively. Using these 2 techniques, Arabidopsis thaliana cultured with 0 mg/L (control), 0.5 mg/L, 1.5 mg/L, and 5.0 mg/L Cd(2+) for 16 d was used to analyze the DNA damage and methylation changes as a result of cadmium (Cd). The DNA was amplified by 14 AFLP primer pairs and 13 MSAP primer combinations. In the AFLP experiment, 62 polymorphic sites were found in the patterns of 11 primer combinations and a total of 1116 fragments were obtained in these patterns. There were no polymorphic bands in the remaining 3 pairs. The proportions of polymorphic sites in the 0.5-mg/L Cd(2+) and 5.0-mg/L Cd(2+) treatments were significantly different. Seven polymorphic fragments were then separated and successfully sequenced, yielding 6 nucleobase substitutions and 1 nucleobase deletion. Similarly, in the MSAP experiment, the MSAP% and number of demethylated-type bands were unchanged after Cd treatment, but the number of methylated-type bands was increased significantly in the 5.0-mg/L Cd(2+) treatment group, a finding that may be associated with the AFLP results. The polymorphic bands were also sequenced and the functions of their homologous genes were determined. The DNA damage and methylation changes may be the primary cause of certain pathology changes as a result of Cd uptake in plants. © 2015 SETAC.

Compositions and methods for detecting single nucleotide polymorphisms

DOEpatents

Yeh, Hsin-Chih; Werner, James; Martinez, Jennifer S.

2016-11-22

Described herein are nucleic acid based probes and methods for discriminating and detecting single nucleotide variants in nucleic acid molecules (e.g., DNA). The methods include use of a pair of probes can be used to detect and identify polymorphisms, for example single nucleotide polymorphism in DNA. The pair of probes emit a different fluorescent wavelength of light depending on the association and alignment of the probes when hybridized to a target nucleic acid molecule. Each pair of probes is capable of discriminating at least two different nucleic acid molecules that differ by at least a single nucleotide difference. The methods can probes can be used, for example, for detection of DNA polymorphisms that are indicative of a particular disease or condition.

[Tissue-specific Changes in the Polymorphism of Simple Repeats in DNA of the Offspring of Different Sex Born from Irradiated Male or Female Mice].

PubMed

Lomaeva, M G; Fomenko, L A; Vasil'eva, G V; Bezlepkin, V G

2016-01-01

Evidence is presented indicating the differences in the polymorphism of microsatellite (MCS) repeats in DNA of somatic tissues in the offspring of BALB/c mice of different sex born from preconceptionally irradiated males or females. Brother-sister groups of the offspring born by non-irradiated parental pairs were compared with the offspring obtained after the irradiation of one parent in the same pairs. The number of MCS repeats in DNA of somatic tissues of the offspring from irradiated males or females was compared by a polymerase chain reaction using an arbitrary primer. It was found that changes in the polymorphism of the number of MCS repeats in the offspring from the males irradiated at a dose of 2 Gy was insignificant as compared with the offspring from control animals. In the offspring born by the females irradiated at a dose of 2 Gy (which does not impair the reproductive capacity), a statistically significant increase in the polymorphism was observed. Changes in the polymorphism were different in the offspring of different sex. A higher level of polymorphism was revealed in the female offspring born from the females of the F0 generation after their irradiation at a dose of 2 Gy. The increase in the polymorphism of the number of MCS repeats in DNA was more pronounced in postmitotic tissues compared with proliferating tissues.

Useful DNA polymorphisms are identified by snapback, a midrepetitive element in Tribolium castaneum.

PubMed

Stuart, J J; De Gortari, M J; Hall, P S; Maxwell, M E; Mocelin, G; Brown, S J; Muir, W M

1996-06-01

The red flour bettle, Tribolium castaneum, is both a pest of stored grain products and an important experimental organism. To improve its facility as a genetic model, we are developing DNA fingerprinting methods for this insect. A Tribolium DNA fragment, snapback-1 (SBI), identified among sequences that reassociate before a Cot of 0.03 mol.s/L, was found to produce a banding pattern in restriction endonuclease digested genomic DNA that is characteristic of a midrepetitive element. DNA fingerprints of individual beetles demonstrated that unvarying inherited DNA polymorphism is revealed, and that polymorphism is inherited in a dominant Mendelian fashion. Linkage between bands was minimal. The sequence of SBI was determined, and hybridization experiments indicated that SBI is a fragment of a larger midrepetitive element. Fingerprinting individuals with known inbreeding coefficients indicated that SBI loci have relatively high mutation rates. The possibility that SBI is a fragment of a transposable element is discussed.

[Multilocus genotyping of polymorphous STR-loci of chromosomal DNA in individual cells: technical difficulties].

PubMed

Ivanov, P L; Leonov, S N; Zemskova, E Iu; Kobylianskiĭ, A G; Dziubenko, E V

2013-01-01

This study was designed to estimate the effectiveness of special technical procedures for the enhancement of sensitivity of multiplex analysis of DNA, such as the use of low-plexity PCR systems and the whole genome preamplification technology, and the possibility of their application for the purpose of forensic medical genotyping of polymorphous STR-loci of chromosomal DNA in individual cells. The authors refused to use the imitation model (equivalent DNA dilutions) for the sake of obtaining the maximally informative data and chose to work with real preparations of solitary buccal epithelial cells isolated by the laser microdissection technique. It was shown that neither the use of the low-plexity multilocus PCR systems nor the whole genome pre-amplification technology makes possible reliable genotyping of STR-loci of chromosomal DNA in individual cells. The proposed techniques allow for DNA genotyping in preparations consisting of 10 diploid cells whereas the methods for reliable genotyping of STR-loci of chromosomal DNA in individual cells remains to be developed.

Determination of genotoxic effects of boron and zinc on Zea mays using protein and random amplification of polymorphic DNA analyses.

PubMed

Erturk, Filiz Aygun; Nardemir, Gokce; Hilal, A Y; Arslan, Esra; Agar, Guleray

2015-11-01

In this research, we aimed to determine genotoxic effects of boron (B) and zinc (Zn) on Zea mays by using total soluble protein content and random amplification of polymorphic DNA (RAPD) analyses. For the RAPD analysis, 16 RAPD primers were found to produce unique polymorphic band profiles on treated maize seedlings. With increased Zn and B concentrations, increased polymorphism rate was observed, while genomic template stability and total soluble protein content decreased. The treatment with Zn was more effective than that of B groups on the levels of total proteins. The obtained results from this study revealed that the total soluble protein levels and RAPD profiles were performed as endpoints of genotoxicity and these analyses can offer useful biomarker assays for the evaluation of genotoxic effects on Zn and B polluted plants. © The Author(s) 2013.

Initial determination of DNA polymorphism of some Primula veris L. populations from Kosovo and Austria.

PubMed

Berisha, Naim; Millaku, Fadil; Gashi, Bekim; Krasniqi, Elez; Novak, Johannes

2015-01-01

Primula veris L. (Primulaceae) is a long lived perennial and well known pharmaceutical plant, widely collected for these reasons in almost all SE Europe and particularly in Kosovo. The aim of the study is to determine molecular polymorphism of cowslip (P. veris L.) populations from Kosovo. DNA extracted from leaves were  investigated in details for presence of polymorphism. RAPD analyses were conducted using 20 different short primers. Genomic DNA amplification profiles were analyzed and processed using data labelling. Comparison between cowslip populations in genetic composition revealed that samples from Bogaj were too distinct on their own. Molecular variation was observed to be more within populations (73 %) as compared to among populations (27 %). On the other hand, genetic distance of populations revealed that the highest genetic distance is between Leqinat and Maja e Madhe. Mean values of expected heterozygosity were highest in Bogaj population, while lowest in Maja e Madhe population. The obtained results indicated that Bogaj population are more polymorphic. From the obtained data it can be concluded that RAPD markers provided a useful technique to study genetic diversity in P. veris L. populations. This technology allows identification and assessment of the genetic similarities and differences among plant populations.

Effect of GSTM1 and GSTT1 Polymorphisms on Genetic Damage in Humans Populations Exposed to Radiation From Mobile Towers.

PubMed

Gulati, Sachin; Yadav, Anita; Kumar, Neeraj; Kanupriya; Aggarwal, Neeraj K; Kumar, Rajesh; Gupta, Ranjan

2016-04-01

All over the world, people have been debating about associated health risks due to radiation from mobile phones and mobile towers. The carcinogenicity of this nonionizing radiation has been the greatest health concern associated with mobile towers exposure until recently. The objective of our study was to evaluate the genetic damage caused by radiation from mobile towers and to find an association between genetic polymorphism of GSTM1 and GSTT1 genes and DNA damage. In our study, 116 persons exposed to radiation from mobile towers and 106 control subjects were genotyped for polymorphisms in the GSTM1 and GSTT1 genes by multiplex polymerase chain reaction method. DNA damage in peripheral blood lymphocytes was determined using alkaline comet assay in terms of tail moment (TM) value and micronucleus assay in buccal cells (BMN). There was a significant increase in BMN frequency and TM value in exposed subjects (3.65 ± 2.44 and 6.63 ± 2.32) compared with control subjects (1.23 ± 0.97 and 0.26 ± 0.27). However, there was no association of GSTM1 and GSTT1 polymorphisms with the level of DNA damage in both exposed and control groups.

Identification of two new polymorphisms in the manganese superoxide dismutase gene (Mn-SOD); Part of the etiology of Parkinson`s disease?

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

Eggers, B.; Kurth, J.H.; Kurth, M.C.

1994-09-01

Epidemiological studies suggest that several different environmental agents interact with a number of genetic elements to cause Parkinson`s disease (PD), a common neurodegenerative disease. Abnormalities of oxidative metabolism may be central to this process. Specifically, the production and degradation of dopamine may lead to toxic by-products and increased oxidative stress. Toxic by-products include hydrogen peroxide, superoxide, and hydroxyl radicals, all of which are implicated in the aging process of the central nervous system. Superoxide dismutase (SOD) catalyzes superoxide to hydrogen peroxide. Genetic predisposition to PD may be at least partially a result of certain SOD alleles. Using the cDNA sequencemore » of Mn-SOD gene, oligonucleotide primers were designed which span several presumptive splice junction sites. An approximatley 2.4kb PCR product was amplified from gDNA samples that span one or more intron near the 3{prime} end of the Mn-SOD cDNA sequence. The resultant product was screened with a panel of 4-cutters to identify fragments appropriate for SSCP analysis. Twenty-two gDNA samples were screened for SSCP and size differences of these PCR products. After digestion with AluI, two polymorphisms were observed. Two alleles with a size difference of 2-4 bp were observed by denaturing PAGE in one of the fragments. SSCP analysis revealed a polymorphism with 2 alleles in another fragment. Sequence analysis of these polymorphisms is in progress. DNA from several DEPH families was used to confirm Mendelian inheritance of these polymorphisms. Genomic DNA samples have been collected from 265 PD patients and 169 control individuals; allelic frequencies will be determined for these populations, compared by {chi}{sup 2} analysis, and relative risk calculated. These results may support a contribution of Mn-SOD in the genetic predisposition to PD.« less

Single-Nucleotide Polymorphisms of Genes Involved in Repair of Oxidative DNA Damage and the Risk of Recurrent Depressive Disorder.

PubMed

Czarny, Piotr; Kwiatkowski, Dominik; Toma, Monika; Gałecki, Piotr; Orzechowska, Agata; Bobińska, Kinga; Bielecka-Kowalska, Anna; Szemraj, Janusz; Berk, Michael; Anderson, George; Śliwiński, Tomasz

2016-11-20

BACKGROUND Depressive disorder, including recurrent type (rDD), is accompanied by increased oxidative stress and activation of inflammatory pathways, which may induce DNA damage. This thesis is supported by the presence of increased levels of DNA damage in depressed patients. Such DNA damage is repaired by the base excision repair (BER) pathway. BER efficiency may be influenced by polymorphisms in BER-related genes. Therefore, we genotyped nine single-nucleotide polymorphisms (SNPs) in six genes encoding BER proteins. MATERIAL AND METHODS Using TaqMan, we selected and genotyped the following SNPs: c.-441G>A (rs174538) of FEN1, c.2285T>C (rs1136410) of PARP1, c.580C>T (rs1799782) and c.1196A>G (rs25487) of XRCC1, c.*83A>C (rs4796030) and c.*50C>T (rs1052536) of LIG3, c.-7C>T (rs20579) of LIG1, and c.-468T>G (rs1760944) and c.444T>G (rs1130409) of APEX1 in 599 samples (288 rDD patients and 311 controls). RESULTS We found a strong correlation between rDD and both SNPs of LIG3, their haplotypes, as well as a weaker association with the c.-468T>G of APEXI which diminished after Nyholt correction. Polymorphisms of LIG3 were also associated with early onset versus late onset depression, whereas the c.-468T>G polymorphism showed the opposite association. CONCLUSIONS The SNPs of genes involved in the repair of oxidative DNA damage may modulate rDD risk. Since this is an exploratory study, the results should to be treated with caution and further work needs to be done to elucidate the exact involvement of DNA damage and repair mechanisms in the development of this disease.

Single-Nucleotide Polymorphisms of Genes Involved in Repair of Oxidative DNA Damage and the Risk of Recurrent Depressive Disorder

PubMed Central

Czarny, Piotr; Kwiatkowski, Dominik; Toma, Monika; Gałecki, Piotr; Orzechowska, Agata; Bobińska, Kinga; Bielecka-Kowalska, Anna; Szemraj, Janusz; Berk, Michael; Anderson, George; Śliwiński, Tomasz

2016-01-01

Background Depressive disorder, including recurrent type (rDD), is accompanied by increased oxidative stress and activation of inflammatory pathways, which may induce DNA damage. This thesis is supported by the presence of increased levels of DNA damage in depressed patients. Such DNA damage is repaired by the base excision repair (BER) pathway. BER efficiency may be influenced by polymorphisms in BER-related genes. Therefore, we genotyped nine single-nucleotide polymorphisms (SNPs) in six genes encoding BER proteins. Material/Methods Using TaqMan, we selected and genotyped the following SNPs: c.-441G>A (rs174538) of FEN1, c.2285T>C (rs1136410) of PARP1, c.580C>T (rs1799782) and c.1196A>G (rs25487) of XRCC1, c.*83A>C (rs4796030) and c.*50C>T (rs1052536) of LIG3, c.-7C>T (rs20579) of LIG1, and c.-468T>G (rs1760944) and c.444T>G (rs1130409) of APEX1 in 599 samples (288 rDD patients and 311 controls). Results We found a strong correlation between rDD and both SNPs of LIG3, their haplotypes, as well as a weaker association with the c.-468T>G of APEXI which diminished after Nyholt correction. Polymorphisms of LIG3 were also associated with early onset versus late onset depression, whereas the c.-468T>G polymorphism showed the opposite association. Conclusions The SNPs of genes involved in the repair of oxidative DNA damage may modulate rDD risk. Since this is an exploratory study, the results should to be treated with caution and further work needs to be done to elucidate the exact involvement of DNA damage and repair mechanisms in the development of this disease. PMID:27866211

[Gene polymorphisms in patients with Down's syndrome].

PubMed

Kuz'mina, N S; Ushenkova, L I; Shagirova, Zh M; Sheĭkhaev, G O; Mikhaĭlov, V F; Kurbatova, L A; Mazurik, V K; Rubanovich, A V; Zasukhina, G D

2009-01-01

Polymorphisms of glutation-S-transferase (GSTM1, GSTT1 GSTP1) and methylentetrahydrofolate reductase (MTHFR) genes have been studied in DNA from blood lymphocytes of 18 patients with Down's syndrome and 61 controls. Frequencies of normal alleles of GST genotypes were lower in patients as compared to the controls. A DNA analysis of 11 patients and 17 controls revealed the presence of mutations in region 246-250 of exon 7 of the p53 gene in 4 patients. Mutations were not found in the control group. Due to the small sample size, the results of this study should be interpreted with caution and need replication in larger studies.

Restriction fragment length polymorphism among Israeli Holstein-Friesian dairy bulls.

PubMed

Beckmann, J S; Kashi, Y; Hallerman, E M; Nave, A; Soller, M

1986-01-01

Israeli Holstein-Friesian dairy bulls were screened for restriction fragment length polymorphisms by hybridizing cloned DNA probes for bovine growth hormone, for chymosin, and for rat muscle beta-actin to restriction endonuclease-digested DNA immobilized on nitrocellulose filters. The population proved to be polymorphic at the growth hormone locus, with evidence consistent with the phenotypes being inherited in allelic fashion. A low level of polymorphism was also observed at one of the beta-actin gene family loci. The chymosin locus was monomorphic with the restriction enzymes utilized. The results illustrate the power of restriction fragment length polymorphism methodology in visualizing genetic variability in dairy cattle populations.

Fluorescence-labeled methylation-sensitive amplified fragment length polymorphism (FL-MS-AFLP) analysis for quantitative determination of DNA methylation and demethylation status.

PubMed

Kageyama, Shinji; Shinmura, Kazuya; Yamamoto, Hiroko; Goto, Masanori; Suzuki, Koichi; Tanioka, Fumihiko; Tsuneyoshi, Toshihiro; Sugimura, Haruhiko

2008-04-01

The PCR-based DNA fingerprinting method called the methylation-sensitive amplified fragment length polymorphism (MS-AFLP) analysis is used for genome-wide scanning of methylation status. In this study, we developed a method of fluorescence-labeled MS-AFLP (FL-MS-AFLP) analysis by applying a fluorescence-labeled primer and fluorescence-detecting electrophoresis apparatus to the existing method of MS-AFLP analysis. The FL-MS-AFLP analysis enables quantitative evaluation of more than 350 random CpG loci per run. It was shown to allow evaluation of the differences in methylation level of blood DNA of gastric cancer patients and evaluation of hypermethylation and hypomethylation in DNA from gastric cancer tissue in comparison with adjacent non-cancerous tissue.

Unraveling the sequence-dependent polymorphic behavior of d(CpG) steps in B-DNA.

PubMed

Dans, Pablo Daniel; Faustino, Ignacio; Battistini, Federica; Zakrzewska, Krystyna; Lavery, Richard; Orozco, Modesto

2014-10-01

We have made a detailed study of one of the most surprising sources of polymorphism in B-DNA: the high twist/low twist (HT/LT) conformational change in the d(CpG) base pair step. Using extensive computations, complemented with database analysis, we were able to characterize the twist polymorphism in the d(CpG) step in all the possible tetranucleotide environment. We found that twist polymorphism is coupled with BI/BII transitions, and, quite surprisingly, with slide polymorphism in the neighboring step. Unexpectedly, the penetration of cations into the minor groove of the d(CpG) step seems to be the key element in promoting twist transitions. The tetranucleotide environment also plays an important role in the sequence-dependent d(CpG) polymorphism. In this connection, we have detected a previously unexplored intramolecular C-H···O hydrogen bond interaction that stabilizes the low twist state when 3'-purines flank the d(CpG) step. This work explains a coupled mechanism involving several apparently uncorrelated conformational transitions that has only been partially inferred by earlier experimental or theoretical studies. Our results provide a complete description of twist polymorphism in d(CpG) steps and a detailed picture of the molecular choreography associated with this conformational change. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Chloroplast DNA Diversity among Trees, Populations and Species in the California Closed-Cone Pines (Pinus Radiata, Pinus Muricata and Pinus Attenuata)

PubMed Central

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

DNA repair gene polymorphisms and risk of cutaneous melanoma: a systematic review and meta-analysis.

PubMed

Mocellin, Simone; Verdi, Daunia; Nitti, Donato

2009-10-01

Polymorphisms of DNA repair-related genes might modulate cancer predisposition. We performed a systematic review and meta-analysis of the available evidence regarding the relationship between these polymorphisms and the risk of developing cutaneous melanoma. Relevant studies were searched using PubMed, Medline, Embase, Cancerlit, Cochrane and ISI Web of Knowledge databases. Data were gathered according to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. The model-free approach was adopted to perform the meta-analysis of the retrieved data. We identified 20 original reports that describe the relationship between melanoma risk and the single-nucleotide polymorphisms (SNPs) of 16 genes (cases = 4195). For seven SNPs considered in at least two studies, the findings were heterogeneous. Data were suitable for meta-analysis only in the case of the XPD/ERCC2 SNP rs13181 (cases = 2308, controls = 3698) and demonstrated that the variant C allele is associated with increased melanoma risk (odds ratio = 1.12, 95% confidence interval = 1.03-1.21, P = 0.01; population attributable risk = 9.6%). This is the first meta-analysis suggesting that XPD/ERCC2 might represent a low-penetrance melanoma susceptibility gene. Much work is still to be done before definitive conclusions can be drawn on the role of DNA repair alterations in melanomagenesis since for the other genes involved in this highly complex process, the available information is scarce or null.

The association of folate pathway and DNA repair polymorphisms with susceptibility to childhood acute lymphoblastic leukemia.

PubMed

Goričar, Katja; Erčulj, Nina; Faganel Kotnik, Barbara; Debeljak, Maruša; Hovnik, Tinka; Jazbec, Janez; Dolžan, Vita

2015-05-15

Genetic factors may play an important role in susceptibility to childhood acute lymphoblastic leukemia (ALL). The aim of our study was to evaluate the associations of genetic polymorphisms in folate pathway and DNA repair genes with susceptibility to ALL. In total, 121 children with ALL and 184 unrelated healthy controls of Slovenian origin were genotyped for 14 polymorphisms in seven genes of folate pathway, base excision repair and homologous recombination repair (TYMS, MTHFR, OGG1, XRCC1, NBN, RAD51, and XRCC3). In addition, the exon 6 of NBN was screened for the presence of mutations using denaturing high performance liquid chromatography. Twelve polymorphisms were in Hardy-Weinberg equilibrium in controls and their genotype frequencies were in agreement with those reported in other Caucasian populations. Among the investigated polymorphisms and mutations, NBN Glu185Gln significantly decreased susceptibility to B-cell ALL (p=0.037), while TYMS 3R allele decreased susceptibility to T-cell ALL (p=0.011). Moreover, significantly decreased susceptibility to ALL was observed for MTHFR TA (p=0.030) and RAD51 GTT haplotypes (p=0.016). Susceptibility to ALL increased with the increasing number of risk alleles (ptrend=0.007). We also observed significant influence of hOGG-RAD51 and NBN-RAD51 interactions on susceptibility to ALL. Our results suggest that combination of several polymorphisms in DNA repair and folate pathways may significantly affect susceptibility to childhood ALL. Copyright © 2015 Elsevier B.V. All rights reserved.

Systematics of gastrointestinal nematodes of domestic ruminants: advances between 1992 and 1995 and proposals for future research.

PubMed

Lichtenfels, J R; Hoberg, E P; Zarlenga, D S

1997-11-01

The systematics of trichostrongyloid nematodes of ruminants provides a foundation for diagnostics and responds to the need to identify eggs in feces, free-living larvae from pastures or fecal cultures and larval or adult nematodes collected from hosts. These needs are associated with diagnostic problems or research projects. Difficulties in identifying all developmental stages of trichostrongyloid nematodes of domestic ruminants still severely limit the effective diagnosis and control of these parasites. Phylogenetic hypotheses as the basis for predictive classifications have been developed only for the subfamilies of the Trichostrongylidae. This report briefly describes recent progress in the development of improved tools for identification, phylogenetic analyses and predictive classifications. It also describes future research needed on the identification and classification of trichostrongyloid nematode parasites of domestic ruminants. Nematodes included are species of the super-family Trichostrongyloidea known to be important pathogens of domestic ruminants. The information summarized is presented by nematode developmental stage and by taxonomic groups. Eggs: While eggs of some trichostrongyloid nematode parasites of ruminants can be readily identified to their genus (Nematodirus), and some to species (e.g. Nematodirus battus), most of the important pathogens (including the Ostertagiinae and Haemonchinae) cannot be identified morphologically or morphometrically even to family level. However, DNA technology has been developed for determining not only the presence of specific pathogens in eggs from fecal samples, but also for estimating the percentage of the total eggs that each pathogen comprises. This new method will make possible a rapid determination of which individual animals in a herd should be treated. Larvae: The most commonly-used method for identifying infective larvae is time-consuming (several weeks), unreliable for estimating intensities of individual species as components of mixed populations and requires highly trained specialists. Available identification keys for larvae are not well illustrated and need to be augmented. Adults: Recent advances in the identification of adult trichostrongyloids and their systematics are organized by taxonomic group. Genera included are Ostertagia, Haemonchus, Cooperia, Trichostrongylus and Nematodirus. Recently, the first phylogenetic analysis of the Trichostrongylidae family established monophyly for the family. A similar analysis of the Molineidae is needed. Ostertagia: Several studies of polymorphism summarized the phenomenon and listed 19 polymorphic species in five genera. Two studies of DNA differences within and among polymorphic species of Ostertagiinae supported earlier hypotheses that the species pairs represent polymorphic species. A phylogenetic analysis of the Ostertagiinae and generic concepts are needed. Haemonchus: A key to three species of Haemonchus provides, for the first time, morphological characteristics for the microscopical identification to species of individual adult nematodes of either sex. The Food and Drug Administration is now requiring that results of drug trials include identification of Haemonchus to species. Cooperia: Studies using random amplified polymorphic DNA methods showed a high degree of variation within and among C. oncophora/C. surnabada, but supported a polymorphic relationship for the species pair. A phylogenetic analysis of the Cooperiinae is needed. Trichostrongylus: Restriction Fragment Length Polymorphisms (RFLPs) of genomic DNA of two strains of T. colubriformis indicated a high degree of intra- and inter-strain DNA polymorphism. However, other studies demonstrated expected species level differences between T. colubriformis and T. vitrinus using Random Amplified Polymorphic DNA (RAPD) methods. Sequences of the second Internal Transcribed Spacer Region (ITS-2) ribosomal repeat showed sequence differences of 1.3-7.6% among five

[The use of multilocus sequence typing (MLST) and randomly amplified polymorphic DNA (RAPD) for the differentiation between strains of Burkholderia mallei].

PubMed

Antonov, V A; Altukhova, V V; Savchenko, S S; Zamaraev, V S; Iliukhin, V I; Alekseev, V V

2007-01-01

Burkholderia mallei is highly pathogenic microorganism for both humans and animals. In this work, the possibility of the use of the genotyping method for differentiation between strains of B. mallei was studied. A collection of 14 isolates of B. mallei was characterized using randomly amplified polymorphic DNA (RAPD) and multilocus sequence typing (MLST). RAPD was the best method used for detecting strain differences of B. mallei. It was suggested that this method would be an increasingly useful molecular epidemiological tool.

Mismatch repair gene MSH3 polymorphism is associated with the risk of sporadic prostate cancer.

PubMed

Hirata, Hiroshi; Hinoda, Yuji; Kawamoto, Ken; Kikuno, Nobuyuki; Suehiro, Yutaka; Okayama, Naoko; Tanaka, Yuichiro; Dahiya, Rajvir

2008-05-01

The mismatch repair system is a DNA repair mechanism that corrects mispaired bases during DNA replication errors. Cancer cells deficient in MMR proteins have a 10(2) to 10(3)-fold increase in the mutation rate. Single nucleotide polymorphisms of mismatch repair genes have been shown to cause a decrease in DNA repair activity. We hypothesized that mismatch repair gene polymorphism could be a risk factor for prostate cancer and p53 Pro/Pro genotype carriers could influence MSH3 and MSH6 polymorphisms. DNA samples from 110 patients with prostate cancer and 110 healthy controls were analyzed by single strand conformational polymorphism and polymerase chain reaction-restriction fragment length polymorphism to determine the genotypic frequency of 5 polymorphic loci on 2 MMR genes (MSH3 and MSH6) and p53 codon72. The chi-square test was applied to compare genotype frequency between patients and controls. A significant increase in the G/A+A/A genotype of MSH3 Pro222Pro was observed in patients compared to controls (OR 1.87, 95% CI 1.0-3.5). The frequency of A/G + G/G genotypes of MSH3 exon23 Thr1036Ala also tended to increase in patients (OR 1.57, 95% CI 0.92-2.72). In p53 codon72 Arg/Pro + Pro/Pro carriers the frequency of the AG + GG genotype of MSH3 exon23 was significantly increased in patients compared to controls (OR 2.1, 95% CI 1.05-4.34). To our knowledge this is the first report of the association of MSH3 gene polymorphisms in prostate cancer. These results suggest that the MSH3 polymorphism may be a risk factor for prostate cancer.

Genetic relatedness of artichoke (Cynara scolymus L.) hybrids using random amplified polymorphic DNA (RAPD) fingerprinting.

PubMed

Sharaf-Eldin, M A; Al-Tamimi, A; Alam, P; Elkholy, S F; Jordan, J R

2015-12-28

The artichoke (Cynara scolymus L.) is an important food and medicinal crop that is cultivated in Mediterranean countries. Morphological characteristics, such as head shape and diameter, leaf shape, and bract shape, are mainly affected by environmental conditions. A molecular marker approach was used to analyze the degree of polymorphism between artichoke hybrid lines. The degree of genetic difference among three artichoke hybrids was evaluated using random amplified polymorphic DNA-PCR (RAPD-PCR). In this study, the DNA fingerprints of three artichoke lines (A13-010, A11-018, and A12-179) were generated, and a total of 10 decamer primers were applied for RAPD-PCR analyses. Polymorphism  (16.66 to 62.50%) was identified using eight arbitrary decamers and total genomic DNA extracted from the hybrids. Of the 59 loci detected, there were 25 polymorphic and 34 monomorphic loci. Jaccard's similarity index (JSI) ranged between 1.0 and 0.84. Based on the unweighted pair group method with arithmetic mean (UPGMA) similarity matrix and dendrogram, the results indicated that two hybrids (A13-010 and A11-018) were closely related to each other, and the A12-179 line showed more divergence. When identifying correct accessions, consideration of the genetic variation and genetic relationships among the genotypes are required. The RAPD-PCR fingerprinting of artichoke lines clearly showed that it is possible to analyze the RAPD patterns for correlation between genetic means and differences or resemblance between close accessions (A13-010 and A11- 018) at the genomic level.

Association between polymorphisms at promoters of XRCC5 and XRCC6 genes and risk of breast cancer.

PubMed

Rajaei, Mehrdad; Saadat, Iraj; Omidvari, Shahpour; Saadat, Mostafa

2014-04-01

Variation in DNA repair genes is one of the mechanisms that may lead to variation in DNA repair capacity. Ku, a heterodimeric DNA-binding complex, is directly involved in repair of DNA double-strand breaks. Ku consists of two subunits, Ku70 and Ku80, which are encoded by the XRCC6 and XRCC5 genes, respectively. In the present study, we investigated whether common genetic variant in variable number of tandem repeats (VNTR) XRCC5 and T-991C XRCC6 was associated with an altered risk of breast cancer. The present study included 407 females with breast cancer and 395 age frequency-matched controls which were randomly selected from the healthy female blood donors. The XRCC5 and XRCC6 polymorphisms were determined using PCR-based methods. For XRCC5 polymorphism, in comparison with the 1R/1R genotype, the 0R/0R genotype increased breast cancer risk (OR 9.55, 95%CI 1.19-76.64, P = 0.034). The 1R/3R genotype compared with 1R/1R genotype decreased the risk of breast cancer (Fisher's exact test P = 0.015). There was no association between T-991C polymorphism of XRCC6 and breast cancer risk. Mean of age at diagnosis of breast cancer for 0, 1, 2, 3, and >4 repeat in XRCC5 were 39.2, 41.9, 44.3, 45.8, and 47.3 years, respectively. The Kaplan-Meier survival analysis revealed that the number of repeat was associated with age at diagnosis of breast cancer (log rank statistic = 13.90, df = 4, P = 0.008). The findings of the present study revealed that either breast cancer risk or age at diagnosis of breast cancer was associated with the VNTR polymorphism at promoter region of XRCC5.

Polymorphisms in DNA repair genes and MDR1 and the risk for non-Hodgkin lymphoma.

PubMed

Kim, Hee Nam; Kim, Nan Young; Yu, Li; Kim, Yeo-Kyeoung; Lee, Il-Kwon; Yang, Deok-Hwan; Lee, Je-Jung; Shin, Min-Ho; Park, Kyeong-Soo; Choi, Jin-Su; Kim, Hyeoung-Joon

2014-04-21

The damage caused by oxidative stress and exposure to cigarette smoke and alcohol necessitate DNA damage repair and transport by multidrug resistance-1 (MDR1). To explore the association between polymorphisms in these genes and non-Hodgkin lymphoma risk, we analyzed 15 polymorphisms of 12 genes in a population-based study in Korea (694 cases and 1700 controls). Four genotypes of DNA repair pathway genes (XRCC1 399 GA, OGG1 326 GG, BRCA1 871 TT, and WRN 787 TT) were associated with a decreased risk for NHL [odds ratio (OR)XRCC1 GA=0.80, p=0.02; OROGG1 GG=0.70, p=0.008; ORBRCA1 TT=0.71, p=0.048; ORWRN TT=0.68, p=0.01]. Conversely, the MGMT 115 CT genotype was associated with an increased risk for NHL (OR=1.25, p=0.04). In the MDR1 gene, the 1236 CC genotype was associated with a decreased risk for NHL (OR=0.74, p=0.04), and the 3435 CT and TT genotypes were associated with an increased risk (OR3435CT=1.50, p<0.0001; OR3435TT=1.43, p=0.02). These results suggest that polymorphisms in the DNA repair genes XRCC1, OGG1, BRCA1, WRN1, and MGMT and in the MDR1 gene may affect the risk for NHL in Korean patients.

Forensic strategy to ensure the quality of sequencing data of mitochondrial DNA in highly degraded samples.

PubMed

Adachi, Noboru; Umetsu, Kazuo; Shojo, Hideki

2014-01-01

Mitochondrial DNA (mtDNA) is widely used for DNA analysis of highly degraded samples because of its polymorphic nature and high number of copies in a cell. However, as endogenous mtDNA in deteriorated samples is scarce and highly fragmented, it is not easy to obtain reliable data. In the current study, we report the risks of direct sequencing mtDNA in highly degraded material, and suggest a strategy to ensure the quality of sequencing data. It was observed that direct sequencing data of the hypervariable segment (HVS) 1 by using primer sets that generate an amplicon of 407 bp (long-primer sets) was different from results obtained by using newly designed primer sets that produce an amplicon of 120-139 bp (mini-primer sets). The data aligned with the results of mini-primer sets analysis in an amplicon length-dependent manner; the shorter the amplicon, the more evident the endogenous sequence became. Coding region analysis using multiplex amplified product-length polymorphisms revealed the incongruence of single nucleotide polymorphisms between the coding region and HVS 1 caused by contamination with exogenous mtDNA. Although the sequencing data obtained using long-primer sets turned out to be erroneous, it was unambiguous and reproducible. These findings suggest that PCR primers that produce amplicons shorter than those currently recognized should be used for mtDNA analysis in highly degraded samples. Haplogroup motif analysis of the coding region and HVS should also be performed to improve the reliability of forensic mtDNA data. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Single nucleotide polymorphisms of DNA repair genes as predictors of radioresponse.

PubMed

Parliament, Matthew B; Murray, David

2010-10-01

Radiation therapy is a key modality in the treatment of cancer. Substantial progress has been made in unraveling the molecular events which underpin the responses of malignant and surrounding normal tissues to ionizing radiation. An understanding of the genes involved in processes such as DNA double-strand break repair, DNA damage response, cell-cycle control, apoptosis, cellular antioxidant defenses, and cytokine production, has evolved toward examination of how genetic variants, most often, single nucleotide polymorphisms (SNPs), may influence interindividual radioresponse. Experimental approaches, such as candidate SNP-association studies, genome-wide association studies, and massively parallel sequencing are being proposed to address these questions. We present a focused review of the evidence supporting an association between SNPs in DNA repair genes and radioresponse in normal tissues and tumors. Although preliminary results indicate possible associations, there are methodological weaknesses in many of the studies, and independent validation of SNPs as biomarkers of radioresponse in much larger cohorts will likely require research cooperation through international consortia. Copyright © 2010 Elsevier Inc. All rights reserved.

Mapped DNA probes from Ioblolly pine can be used for restriction fragment length polymorphism mapping in other conifers

Treesearch

M.R. Ahuja; M.E. Devey; A.T. Groover; K.D. Jermstad; D.B Neale

1994-01-01

A high-density genetic map based on restriction fragment length polymorphisms (RFLPs) is being constructed for loblolly pine (Pinus taeda L.). Consequently, a large number of DNA probes from loblolly pine are potentially available for use in other species. We have used some of these DNA probes to detect RFLPs in 12 conifers and an angiosperm....

Analysis of ploidy and the patterns of amplified fragment length polymorphism and methylation sensitive amplified polymorphism in strawberry plants recovered from cryopreservation.

PubMed

Hao, Yu-Jin; You, Chun-Xiang; Deng, Xui-Xin

2002-01-01

Shoot-tips of 10 strawberry genotypes were successfully cryopreserved using a modified encapsulation-dehydration method. All genotypes survived cryopreservation with high survival and regeneration rates. Eight Joho single-bud sibling lines were established as a model system for genetic analysis. Although cytological examination found chromosomal variation in both non-cryopreserved and cryopreserved samples, the ploidy constitution remained relatively stable after cryopreservation. DNA samples digested with MseI and PstI were used for amplified fragmentation length polymorphism (AFLP) assay. In 16 primer combinations, only one, namely, PCCA-MCAG, detected one site where band pattern changed after cryopreservation, which might be contributed to the change in DNA methylation status at PstI recognition site. Methylation sensitive amplified polymorphism (MSAP) assay was carried out for further investigation on the influence of cryopreservation on DNA methylation status. It was found that cryopreservation induced a significant change in DNA methylation status.

A new strategy for complete identification of sea buckthorn cultivars by using random amplified polymorphic DNA markers.

PubMed

Yang, G; Ding, J; Wu, L R; Duan, Y D; Li, A Y; Shan, J Y; Wu, Y X

2015-03-13

DNA fingerprinting is both a popular and important technique with several advantages in plant cultivar identification. However, this technique has not been used widely and efficiently in practical plant identification because the analysis and recording of data generated from fingerprinting and genotyping are tedious and difficult. We developed a novel approach known as a cultivar identification diagram (CID) strategy that uses DNA markers to separate plant individuals in a more efficient, practical, and referable manner. A CID was manually constructed and a polymorphic marker was generated from each polymerase chain reaction for sample separation. In this study, 67 important sea buckthorn cultivars cultivated in China were successfully separated with random amplified polymorphic DNA markers using the CID analysis strategy, with only seven 11-nucleotide primers employed. The utilization of the CID of these 67 sea buckthorn cultivars was verified by identifying 2 randomly chosen groups of cultivars among the 67 cultivars. The main advantages of this identification strategy include fewer primers used and separation of all cultivars using the corresponding primers. This sea buckthorn CID was able to separate any sea buckthorn cultivars among the 67 studied, which is useful for sea buckthorn cultivar identification, cultivar-right-protection, and for the sea buckthorn nursery industry in China.

Screening and Characterization of RAPD Markers in Viscerotropic Leishmania Parasites

PubMed Central

Mkada–Driss, Imen; Talbi, Chiraz; Guerbouj, Souheila; Driss, Mehdi; Elamine, Elwaleed M.; Cupolillo, Elisa; Mukhtar, Moawia M.; Guizani, Ikram

2014-01-01

Visceral leishmaniasis (VL) is mainly due to the Leishmania donovani complex. VL is endemic in many countries worldwide including East Africa and the Mediterranean region where the epidemiology is complex. Taxonomy of these pathogens is under controversy but there is a correlation between their genetic diversity and geographical origin. With steady increase in genome knowledge, RAPD is still a useful approach to identify and characterize novel DNA markers. Our aim was to identify and characterize polymorphic DNA markers in VL Leishmania parasites in diverse geographic regions using RAPD in order to constitute a pool of PCR targets having the potential to differentiate among the VL parasites. 100 different oligonucleotide decamers having arbitrary DNA sequences were screened for reproducible amplification and a selection of 28 was used to amplify DNA from 12 L. donovani, L. archibaldi and L. infantum strains having diverse origins. A total of 155 bands were amplified of which 60.65% appeared polymorphic. 7 out of 28 primers provided monomorphic patterns. Phenetic analysis allowed clustering the parasites according to their geographical origin. Differentially amplified bands were selected, among them 22 RAPD products were successfully cloned and sequenced. Bioinformatic analysis allowed mapping of the markers and sequences and priming sites analysis. This study was complemented with Southern-blot to confirm assignment of markers to the kDNA. The bioinformatic analysis identified 16 nuclear and 3 minicircle markers. Analysis of these markers highlighted polymorphisms at RAPD priming sites with mainly 5′ end transversions, and presence of inter– and intra– taxonomic complex sequence and microsatellites variations; a bias in transitions over transversions and indels between the different sequences compared is observed, which is however less marked between L. infantum and L. donovani. The study delivers a pool of well-documented polymorphic DNA markers, to develop molecular diagnostics assays to characterize and differentiate VL causing agents. PMID:25313833

Genetic Confirmation of Mungbean (Vigna radiata) and Mashbean (Vigna mungo) Interspecific Recombinants using Molecular Markers.

PubMed

Abbas, Ghulam; Hameed, Amjad; Rizwan, Muhammad; Ahsan, Muhammad; Asghar, Muhammad J; Iqbal, Nayyer

2015-01-01

Molecular confirmation of interspecific recombinants is essential to overcome the issues like self-pollination, environmental influence, and inadequacy of morphological characteristics during interspecific hybridization. The present study was conducted for genetic confirmation of mungbean (female) and mashbean (male) interspecific crosses using molecular markers. Initially, polymorphic random amplified polymorphic DNA (RAPD), universal rice primers (URP), and simple sequence repeats (SSR) markers differentiating parent genotypes were identified. Recombination in hybrids was confirmed using these polymorphic DNA markers. The NM 2006 × Mash 88 was most successful interspecific cross. Most of true recombinants confirmed by molecular markers were from this cross combination. SSR markers were efficient in detecting genetic variability and recombination with reference to specific chromosomes and particular loci. SSR (RIS) and RAPD identified variability dispersed throughout the genome. In conclusion, DNA based marker assisted selection (MAS) efficiently confirmed the interspecific recombinants. The results provided evidence that MAS can enhance the authenticity of selection in mungbean improvement program.

Chloroplast SSR polymorphisms in the Compositae and the mode of organellar inheritance in Helianthus annuus.

PubMed

Wills, David M; Hester, Melissa L; Liu, Aizhong; Burke, John M

2005-03-01

Because organellar genomes are often uniparentally inherited, chloroplast (cp) and mitochondrial (mt) DNA polymorphisms have become the markers of choice for investigating evolutionary issues such as sex-biased dispersal and the directionality of introgression. To the extent that organellar inheritance is strictly maternal, it has also been suggested that the insertion of transgenes into either the chloroplast or mitochondrial genomes would reduce the likelihood of gene escape via pollen flow from crop fields into wild plant populations. In this paper we describe the adaptation of chloroplast simple sequence repeats (cpSSRs) for use in the Compositae. This work resulted in the identification of 12 loci that are variable across the family, seven of which were further shown to be highly polymorphic within sunflower (Helianthus annuus). We then used these markers, along with a novel mtDNA restriction fragment length polymorphism (RFLP), to investigate the mode of organellar inheritance in a series of experimental crosses designed to mimic the initial stages of crop-wild hybridization in sunflower. Although we cannot rule out the possibility of extremely rare paternal transmission, our results provide the best evidence to date of strict maternal organellar inheritance in sunflower, suggesting that organellar gene containment may be a viable strategy in sunflower. Moreover, the portability of these markers suggests that they will provide a ready source of cpDNA polymorphisms for use in evolutionary studies across the Compositae.

A genomic landscape of mitochondrial DNA insertions in the pig nuclear genome provides evolutionary signatures of interspecies admixture.

PubMed

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.

Effects of Yangtze River source water on genomic polymorphisms of male mice detected by RAPD.

PubMed

Zhang, Xiaolin; Zhang, Zongyao; Zhang, Xuxiang; Wu, Bing; Zhang, Yan; Yang, Liuyan; Cheng, Shupei

2010-02-01

In order to evaluate the environmental health risk of drinking water from Yangtze River source, randomly amplified polymorphic DNA (RAPD) markers were used to detect the effects of the source water on genomic polymorphisms of hepatic cell of male mice (Mus musculus, ICR). After the mice were fed with source water for 90 days, RAPD-polymerase chain reactions (PCRs) were performed on hepatic genomic DNA using 20 arbitrary primers. Totally, 189 loci were generated, including 151 polymorphic loci. On average, one PCR primer produced 5.3, 4.9 and 4.8 bands for each mouse in the control, the groups fed with source water and BaP solution, respectively. Compared with the control, feeding mice with Yangtze River source water caused 33 new loci to appear and 19 to disappear. Statistical analysis of RAPD printfingers revealed that Yangtze River source water exerted a significant influence on the hepatic genomic polymorphisms of male mice. This study suggests that RAPD is a reliable and sensitive method for the environmental health risk of Yangtze River source water.

Genetic analysis of Apuleia leiocarpa as revealed by random amplified polymorphic DNA markers: prospects for population genetic studies.

PubMed

Lencina, K H; Konzen, E R; Tsai, S M; Bisognin, D A

2016-12-19

Apuleia leiocarpa (Vogel) J.F. MacBride is a hardwood species native to South America, which is at serious risk of extinction. Therefore, it is of prime importance to examine the genetic diversity of this species, information required for developing conservation, sustainable management, and breeding strategies. Although scarcely used in recent years, random amplified polymorphic DNA markers are useful resources for the analysis of genetic diversity and structure of tree species. This study represents the first genetic analysis based on DNA markers in A. leiocarpa that aimed to investigate the levels of polymorphism and to select markers for the precise characterization of its genetic structure. We adapted the original DNA extraction protocol based on cetyltrimethyl ammonium bromide, and describe a simple procedure that can be used to obtain high-quality samples from leaf tissues of this tree. Eighteen primers were selected, revealing 92 bands, from which 75 were polymorphic and 61 were sufficient to represent the overall genetic structure of the population without compromising the precision of the analysis. Some fragments were conserved among individuals, which can be sequenced and used to analyze nucleotide diversity parameters through a wider set of A. leiocarpa individuals and populations. The individuals were separated into 11 distinct groups with variable levels of genetic diversity, which is important for selecting desirable genotypes and for the development of a conservation and sustainable management program. Our results are of prime importance for further investigations concerning the genetic characterization of this important, but vulnerable species.

Molecular characterization of the canine mitochondrial DNA control region for forensic applications.

PubMed

Eichmann, Cordula; Parson, Walther

2007-09-01

The canine mitochondrial DNA (mtDNA) control region of 133 dogs living in the area around Innsbruck, Austria was sequenced. A total of 40 polymorphic sites were observed in the first hypervariable segment and 15 in the second, which resulted in the differentiation of 40 distinct haplotypes. We observed five nucleotide positions that were highly polymorphic within different haplogroups, and they represent good candidates for mtDNA screening. We found five point heteroplasmic positions; all located in HVS-I and a polythymine region in HVS-II, the latter often being associated with length heteroplasmy. In contrast to human mtDNA, the canine control region contains a hypervariable 10 nucleotide repeat region, which is located between the two hypervariable regions. In our population sample, we observed eight different repeat types, which we characterized by direct sequencing and fragment length analysis. The discrimination power of the canine mtDNA control region was 0.93, not taking the polymorphic repeat region into consideration.

[ISSR analysis for genetic polymorphism of Aconitum leucostomum from different habitats].

PubMed

Gao, Fu-chun; Sun, Yun; Zhang, Jing; Zhang, Fan

2014-01-01

To investigate the genetic diversities and variations of Aconitum leucostomum,and to supply essential characteristics for identifying Aconitum crude drugs. Plant genome extraction kit was applied to extract DNA,and ultraviolet spectrophotometer was used to detect the concentrations and purity of DNA. 60 ISSR primers were screened to analyze the DNA of Aconitum leucostomum from 10 habitats. Biosoftwares including POPGEN32 and NTSYS-PC were used to analyze the polymorphic bands obtained, and hence to yield the genetic similarity coefficient of the 10 habitats and map the related graphics, and cluster analysis were performed by UPGMA method. 11 primers selected from 60 ISSR primers were used for amplification and a total of 101 DNA bands were obtained, including 89 polymorphic bands,the average percentage of polymorphic bands (PPB) was 88.1%. Shannon information index (I) was 0.5298, the genetic similarity coefficient (H) was 0.3648, observed number of alleles was 1.8911, and effective number of alleles was 1.6555. The genetic identity was from 0.4950 to 0.6931, and the genetic distances were from 0.3666 to 0.7031. According to cluster analysis result of ISSR, the 10 habitats of Aconitum leucostomum were classified into five groups. Germplasm resources of Aconitum leucostomum show abundant polymorphism and higher genetic variation, which might supply molecular level basis, and provide basis for building DNA fingerprint.

Mitochondrial DNA G10398A variant is not associated with breast cancer in African-American women

PubMed Central

Setiawan, Veronica Wendy; Chu, Li-Hao; John, Esther M.; Ding, Yuan Chun; Ingles, Sue A.; Bernstein, Leslie; Press, Michael F.; Ursin, Giske; Haiman, Christopher A.; Neuhausen, Susan L

2009-01-01

Mitochondria play important roles in cellular energy production, free radical generation and apoptosis. In a previous report in Cancer Research, the mitochondrial DNA (mtDNA) G10398A (Thr → Ala) polymorphism was associated with breast cancer risk in African-American women. Here, we seek to replicate the association by genotyping the G10398A polymorphism in three established population-based case-control studies of breast cancer in African-American women. The 10398A allele was not significantly associated with risk in any of the studies [San Francisco study (542 cases, 282 controls, odds ratio (OR) = 1.73; 95% confidence interval (CI): 0.87, 3.47, P = 0.12); Multiethnic Cohort (391 cases, 460 controls, OR = 1.08; 95% CI: 0.62, 1.86, P = 0.79); CARE/LIFE study (524 cases, 236 controls, OR = 0.81; 95% CI: 0.43, 1.52, P = 0.50)]. When pooling the data across the three studies (1456 cases and 978 controls), no significant association was observed with the 10398A allele (OR = 1.14; 95% CI: 0.80, 1.62, P = 0.47, P heterogeneity=0.30). In analysis of advanced breast cancer cases (n=674), there also was no significant association (OR = 1.18; 95% CI: 0.76, 1.82, P = 0.46). Our results do not support the hypothesis that the mtDNA G10398A polymorphism is a marker of breast cancer risk in African Americans as previously reported. PMID:18262047

Genome-wide single-nucleotide polymorphism arrays demonstrate high fidelity of multiple displacement-based whole-genome amplification.

PubMed

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.

A Natural Polymorphism in rDNA Replication Origins Links Origin Activation with Calorie Restriction and Lifespan

PubMed Central

Kwan, Elizabeth X.; Foss, Eric J.; Tsuchiyama, Scott; Alvino, Gina M.; Kruglyak, Leonid; Kaeberlein, Matt; Raghuraman, M. K.; Brewer, Bonita J.; Kennedy, Brian K.; Bedalov, Antonio

2013-01-01

Aging and longevity are complex traits influenced by genetic and environmental factors. To identify quantitative trait loci (QTLs) that control replicative lifespan, we employed an outbred Saccharomyces cerevisiae model, generated by crossing a vineyard and a laboratory strain. The predominant QTL mapped to the rDNA, with the vineyard rDNA conferring a lifespan increase of 41%. The lifespan extension was independent of Sir2 and Fob1, but depended on a polymorphism in the rDNA origin of replication from the vineyard strain that reduced origin activation relative to the laboratory origin. Strains carrying vineyard rDNA origins have increased capacity for replication initiation at weak plasmid and genomic origins, suggesting that inability to complete genome replication presents a major impediment to replicative lifespan. Calorie restriction, a conserved mediator of lifespan extension that is also independent of Sir2 and Fob1, reduces rDNA origin firing in both laboratory and vineyard rDNA. Our results are consistent with the possibility that calorie restriction, similarly to the vineyard rDNA polymorphism, modulates replicative lifespan through control of rDNA origin activation, which in turn affects genome replication dynamics. PMID:23505383

A natural polymorphism in rDNA replication origins links origin activation with calorie restriction and lifespan.

PubMed

Kwan, Elizabeth X; Foss, Eric J; Tsuchiyama, Scott; Alvino, Gina M; Kruglyak, Leonid; Kaeberlein, Matt; Raghuraman, M K; Brewer, Bonita J; Kennedy, Brian K; Bedalov, Antonio

2013-01-01

Aging and longevity are complex traits influenced by genetic and environmental factors. To identify quantitative trait loci (QTLs) that control replicative lifespan, we employed an outbred Saccharomyces cerevisiae model, generated by crossing a vineyard and a laboratory strain. The predominant QTL mapped to the rDNA, with the vineyard rDNA conferring a lifespan increase of 41%. The lifespan extension was independent of Sir2 and Fob1, but depended on a polymorphism in the rDNA origin of replication from the vineyard strain that reduced origin activation relative to the laboratory origin. Strains carrying vineyard rDNA origins have increased capacity for replication initiation at weak plasmid and genomic origins, suggesting that inability to complete genome replication presents a major impediment to replicative lifespan. Calorie restriction, a conserved mediator of lifespan extension that is also independent of Sir2 and Fob1, reduces rDNA origin firing in both laboratory and vineyard rDNA. Our results are consistent with the possibility that calorie restriction, similarly to the vineyard rDNA polymorphism, modulates replicative lifespan through control of rDNA origin activation, which in turn affects genome replication dynamics.

Molecular identification and genetic variation of varieties of Styphnolobium japonicum (Fabaceae) using SRAP markers.

PubMed

Sun, R X; Zhang, C H; Zheng, Y Q; Zong, Y C; Yu, X D; Huang, P

2016-05-06

Thirty-four Styphnolobium japonicum varieties were analyzed using sequence-related amplified polymorphism (SRAP) markers, to investigate genetic variation and test the effectiveness of SRAP markers in DNA fingerprint establishment. Twelve primer pairs were selected from 120 primer combinations for their reproducibility and high polymorphism. We found a total of 430 amplified fragments, of which 415 fragments were considered polymorphic with an average of 34.58 polymorphic fragments for each primer combination. The percentage of polymorphic fragments was 96.60%, and four primer pairs showed 100% polymorphism. Moreover, simple matched coefficients ranged between 0.68 and 0.89, with an average of 0.785, indicating that the genetic variation among varieties was relatively low. This could be because of the narrow genetic basis of the selected breeding material. Based on the similarity coefficient value of 0.76, the varieties were divided into four major groups. In addition, abundant and clear SRAP fingerprints were obtained and could be used to establish DNA fingerprints. In the DNA fingerprints, each variety had its unique pattern that could be easily distinguished from others. The results demonstrated that 34 varieties of S. japonicum had a relatively narrow genetic variation. Hence, a broadening of the genetic basis of breeding material is necessary. We conclude that establishment of DNA fingerprint is feasible by means of SRAP markers.

Typing single polymorphic nucleotides in mitochondrial DNA as a way to access Middle Pleistocene DNA

PubMed Central

Valdiosera, Cristina; García, Nuria; Dalén, Love; Smith, Colin; Kahlke, Ralf-Dietrich; Lidén, Kerstin; Angerbjörn, Anders; Arsuaga, Juan Luis; Götherström, Anders

2006-01-01

In this study, we have used a technique designed to target short fragments containing informative mitochondrial substitutions to extend the temporal limits of DNA recovery and study the molecular phylogeny of Ursus deningeri. We present a cladistic analysis using DNA recovered from 400 kyr old U. deningeri remains, which demonstrates U. deningeri's relation to Ursus spelaeus. This study extends the limits of recovery from skeletal remains by almost 300 kyr. Plant material from permafrost environments has yielded DNA of this age in earlier studies, and our data suggest that DNA in teeth from cave environments may be equally well preserved. PMID:17148299

An association analysis between mitochondrial DNA content, G10398A polymorphism, HPV infection, and the prognosis of cervical cancer in the Chinese Han population.

PubMed

Feng, Dali; Xu, Hui; Li, Xin; Wei, Yuehua; Jiang, Huangang; Xu, Hong; Luo, Aihua; Zhou, Fuxiang

2016-04-01

The aim was to analyze quantitative (mitochondrial DNA (mtDNA) content) and qualitative (G10398A polymorphism) mtDNA alterations as well as human papillomavirus (HPV) infection in cervical cancer prognosis. One hundred and twenty-two cases of formalin-fixed paraffin-embedded cervical carcinoma specimens were collected from the Yichang Tumor Hospital and Zhongnan Hospital of Wuhan University in the recent 10 years together with medical records. A quantitative real-time PCR (RT-PCR) was used to determine the copy number of the mitochondrial DNA and HPV expression levels. G10398A polymorphism was determined by PCR-RFLP assay. The overall survival of patients with higher mtDNA content was significantly reduced compared with lower mtDNA content patients (P = 0.029). But there was no difference of prognosis between the mtDNA 10398 A allele and G allele. However, the Kaplan-Meier survival curve illustrated a significantly reduced overall survival in the patients with 10398A plus high mtDNA copy number compared with the other groups (P < 0.05). Although no association between HPV expression level and cervical cancer prognosis was observed, 10398A got increased mtDNA content compared with 10398G (P < 0.05) and 10398G displayed an increased HPV-positive rate compared with 10398A. Furthermore, HPV-18 and mtDNA content were positively related in the younger subgroup (≤45 years) (correlation coefficient = 0.456, P = 0.022). This study indicated that mtDNA content and HPV infection status are associated with cervical cancer prognosis. High mitochondrial DNA content plus 10398 A may be a marker of poor prognosis in cervical cancer. And mtDNA variation may potentially influence the predisposition to HPV infection and cervical carcinogenesis.

Inter- and Intraspecific Identification of the New World Screwworm Using Random Amplified Polymorphic DNA-Polymerase Chain Reaction

USDA-ARS?s Scientific Manuscript database

New World screwworms (NWS), Cochliomyia hominivorax (Coquerel), are one of the most important arthropod pests of livestock in the Western Hemisphere. Early instars are very difficult to distinguish morphologically from several closely related blow fly species. Random amplified polymorphic DNA polyme...

Identification of the Kna/Knb polymorphism and a method for Knops genotyping

PubMed Central

Moulds, J.M.; Thomas, B.J.; Doumbo, O.; Diallo, D.A.; Lyke, K.E.; Plowe, C.V.; Rowe, J.A.; Birmingham, D.J.

2010-01-01

BACKGROUND: DNA mutations resulting in the McCoy and Swain-Langley polymorphisms have been identified on complement receptor 1 (CR1)—a ligand for rosetting of Plasmodium falciparum-infected RBCs. The molecular identification of the Kna/Knb polymorphism was sought to develop a genotyping method for use in the study of the Knops blood group and malaria. STUDY DESIGN AND METHODS: CR1 deletion constructs were used in inhibition studies of anti-Kna. PCR amplification of Exon 29 was followed by DNA sequencing. A PCR-RFLP was developed with NdeI, BsmI, and MfeI for the detection of Kna/Knb, McCa/McCb, and Sl1/Sl2, respectively. Knops phenotypes were determined with standard serologic techniques. RESULTS: A total of 310 Malian persons were phenotyped for Kna with 200 (64%) Kn(a+) and 110 (36%) Kn(a−). Many of the Kn(a−) exhibited the Knops-null phenotype, that is, Helgeson. The Kna/b DNA polymorphism was identified as a V1561M mutation with allele frequencies of Kna (V1561) 0.9 and Knb (M1561) 0.1. CONCLUSION: The high frequency (18%) of Knb in West African persons suggests that it is not solely a Caucasian trait. Furthermore, because of the high incidence of heterozygosity as well as amorphs, accurate Knops typing of donors of African descent is best accomplished by a combination of molecular and serologic techniques. PMID:14962306

5,10-methylenetetrahydrofolate reductase (MTHFR) polymorphisms and the risk of acute lymphoblastic leukemia (ALL) in Filipino children.

PubMed

Alcasabas, Patricia; Ravindranath, Yaddanapudi; Goyette, Gerard; Haller, Andrew; Del Rosario, Luz; Lesaca-Medina, Maria Ysabel; Darga, Linda; Ostrea, Enrique M; Taub, Jeffrey W; Everson, Richard B

2008-08-01

5,10-Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism. Polymorphisms at the C677T and A1298C loci are associated with reduced activity; consequently more folate substrates are shunted toward thymidylate and DNA synthesis. Several studies have reported a reduced risk of developing ALL in children with MTHFR polymorphisms. The objective of this study was to determine the association between MTHFR polymorphisms and ALL in Filipino children. We conducted a case control study in children diagnosed with ALL at the Philippine General Hospital from 1/2001 through 12/2005. Bone marrow aspirate slides were reviewed by two expert hematologists to verify the morphologic diagnosis of ALL. DNA was isolated from the slides and MTHFR polymorphisms, C677T and A1298C, were determined using Taqman real-time PCR. Cord blood of healthy Filipino newborns served as control. There were a total of 191 ALL and 394 controls genotyped. The distribution of C677T polymorphisms was similar in the two groups (P = 1.0). However, for A1298C, there was significantly more AC and CC genotypes in the ALL compared to controls (P = 0.02; OR 1.57; CI: 1.08-2.28). The 1298C allele frequency for the control group was 36.8% and 677T allele frequency was 9.9%. A1298C polymorphisms is associated with an increased risk for ALL in Filipino children. This may be due to a difference in leukemia biology or to a high prevalence of folate deficiency in Filipinos. Our study reiterates the gene and environment interaction in leukemogenesis.

The effect of FokI vitamin D receptor polymorphism on bone mineral density in Jordanian perimenopausal women

PubMed Central

Kanan, Raed M.

2013-01-01

CONTEXT: Osteoporosis is a polygenic, multifactorial disease that is characterized by demineralization of bone, and thus presented with decreasing bone mineral mass. Vitamin D receptor (VDR) gene polymorphisms in the 3’-end region (as determined by the enzymes BsmI and ApaI) have been inconsistently associated with bone mineral mass. Another important VDR start codon polymorphism (as determined by the enzyme FokI) has been found to be related to adult bone mineral density (BMD) in pre-and post-menopausal American women. AIMS: This study aims to investigate the prevalence of the FokI VDR gene polymorphism in Jordanian perimenopausal women and study its relationship with bone mineral density. MATERIALS AND METHODS: DNA was isolated from 90 controls (Mean age = 50.41 ± 1.29 y), and 120 patients with symptomatic vertebral fractures (Mean age = 49.14 ± 3.19 y). Restriction Fragment Length Polymorphism (RFLP) analysis of FokI was performed on DNA samples. STATISTICAL ANALYSIS: Data was analyzed using SPSS v19 and Microsoft Excel 2007. RESULTS: The results showed that in controls, the FF (−0.70 ± 0.51) genotype is associated with high lumbar spine BMD Z-score as compared to Ff (−1.25 ± 0.26) and ff (−1.66 ± 0.47) genotypes (P = 0.0095). In patients, the ff genotype was associated with lower lumbar spine BMD in T-score (−2.31 ± 0.17) and Z-score (−1.56 ± 0.09) genotypes (P = 0.031). No significant association was seen in the femoral neck BMD. CONCLUSION: FokI polymorphism may be associated with low BMD in our studied population; however, further studies including other polymorphisms and large sample number are needed. PMID:24019627

Mitochondrial sequence analysis for forensic identification using pyrosequencing technology.

PubMed

Andréasson, H; Asp, A; Alderborn, A; Gyllensten, U; Allen, M

2002-01-01

Over recent years, requests for mtDNA analysis in the field of forensic medicine have notably increased, and the results of such analyses have proved to be very useful in forensic cases where nuclear DNA analysis cannot be performed. Traditionally, mtDNA has been analyzed by DNA sequencing of the two hypervariable regions, HVI and HVII, in the D-loop. DNA sequence analysis using the conventional Sanger sequencing is very robust but time consuming and labor intensive. By contrast, mtDNA analysis based on the pyrosequencing technology provides fast and accurate results from the human mtDNA present in many types of evidence materials in forensic casework. The assay has been developed to determine polymorphic sites in the mitochondrial D-loop as well as the coding region to further increase the discrimination power of mtDNA analysis. The pyrosequencing technology for analysis of mtDNA polymorphisms has been tested with regard to sensitivity, reproducibility, and success rate when applied to control samples and actual casework materials. The results show that the method is very accurate and sensitive; the results are easily interpreted and provide a high success rate on casework samples. The panel of pyrosequencing reactions for the mtDNA polymorphisms were chosen to result in an optimal discrimination power in relation to the number of bases determined.

Polymorphisms in metabolism and repair genes affects DNA damage caused by open-cast coal mining exposure.

PubMed

Espitia-Pérez, Lyda; Sosa, Milton Quintana; Salcedo-Arteaga, Shirley; León-Mejía, Grethel; Hoyos-Giraldo, Luz Stella; Brango, Hugo; Kvitko, Katia; da Silva, Juliana; Henriques, João A P

2016-09-15

Increasing evidence suggest that occupational exposure to open-cast coal mining residues like dust particles, heavy metals and Polycyclic Aromatic Hydrocarbons (PAHs) may cause a wide range of DNA damage and genomic instability that could be associated to initial steps in cancer development and other work-related diseases. The aim of our study was to evaluate if key polymorphisms in metabolism genes CYP1A1Msp1, GSTM1Null, GSTT1Null and DNA repair genes XRCC1Arg194Trp and hOGG1Ser326Cys could modify individual susceptibility to adverse coal exposure effects, considering the DNA damage (Comet assay) and micronucleus formation in lymphocytes (CBMN) and buccal mucosa cells (BMNCyt) as endpoints for genotoxicity. The study population is comprised of 200 healthy male subjects, 100 open-cast coal-mining workers from "El Cerrejón" (world's largest open-cast coal mine located in Guajira - Colombia) and 100 non-exposed referents from general population. The data revealed a significant increase of CBMN frequency in peripheral lymphocytes of occupationally exposed workers carrying the wild-type variant of GSTT1 (+) gene. Exposed subjects carrying GSTT1null polymorphism showed a lower micronucleus frequency compared with their positive counterparts (FR: 0.83; P=0.04), while BMNCyt, frequency and Comet assay parameters in lymphocytes: Damage Index (DI) and percentage of DNA in the tail (Tail % DNA) were significantly higher in exposed workers with the GSTM1Null polymorphism. Other exfoliated buccal mucosa abnormalities related to cell death (Karyorrhexis and Karyolysis) were increased in GSTT/M1Null carriers. Nuclear buds were significantly higher in workers carrying the CYP1A1Msp1 (m1/m2, m2/m2) allele. Moreover, BMNCyt frequency and Comet assay parameters were significantly lower in exposed carriers of XRCC1Arg194Trp (Arg/Trp, Trp/Trp) and hOGG1Ser326Cys (Ser/Cys, Cys/Cys), thereby providing new data to the increasing evidence about the protective role of these polymorphisms. This modulation may involve specific and differentiated pathways in different tissues that also may cause a differential sensitivity related to differential induction of some enzymes. Copyright © 2016 Elsevier B.V. All rights reserved.

Processing and population genetic analysis of multigenic datasets with ProSeq3 software.

PubMed

Filatov, Dmitry A

2009-12-01

The current tendency in molecular population genetics is to use increasing numbers of genes in the analysis. Here I describe a program for handling and population genetic analysis of DNA polymorphism data collected from multiple genes. The program includes a sequence/alignment editor and an internal relational database that simplify the preparation and manipulation of multigenic DNA polymorphism datasets. The most commonly used DNA polymorphism analyses are implemented in ProSeq3, facilitating population genetic analysis of large multigenic datasets. Extensive input/output options make ProSeq3 a convenient hub for sequence data processing and analysis. The program is available free of charge from http://dps.plants.ox.ac.uk/sequencing/proseq.htm.

Association of ACE Gene I/D polymorphism with migraine in Kashmiri population.

PubMed

Wani, Irfan Yousuf; Sheikh, Saleem; Shah, Zafar Amin; Pandith, Arshid A; Wani, Mushtaq; Asimi, Ravouf; Wani, Maqbool; Sheikh, Shahnawaz; Mehraj, Iqra

2016-01-01

Migraine is a complex, recurrent headache disorder that is one of the most common complaints in neurology practice. The role of various genes in its pathogenesis is being studied. We did this study to see whether an association exists between ACE gene I/D polymorphism and migraine in our region. The study included 100 patients diagnosed with migraine and 121 healthy controls. The study subject were age and gender matched. The analysis was based on Polymerase Chain Reaction (PCR) and included following steps: DNA extraction from blood, PCR and Restriction Fragment Length Polymorphism (RFLP). Out of 100 cases, 69 were females and 31 were males. Fifty-seven were having migraine without aura and 43 had migraine with aura. 45 of the cases had II polymorphism, 40 had ID polymorphism and 15 had DD polymorphism in ACE gene. We were not able to find a statistically significant association between ACE gene I/D polymorphism with migraine. The reason for difference in results between our study and other studies could be because of different ethnicity in study populations. So a continuous research is needed in this regard in order to find the genes and different polymorphism that increase the susceptibility of Kashmiri population to migraine.

Phytomonas: analysis of polymorphism and genetic relatedness between isolates from plants and phytophagous insects from different geographic regions by RAPD fingerprints and synapomorphic markers.

PubMed

Serrano, M G; Camargo, E P; Teixeira, M M

1999-01-01

The random amplification of polymorphic DNA was used for easy, quick and sensitive assessment of genetic polymorphism within Phytomonas to discriminate isolates and determine genetic relationships within the genus. We examined 48 Phytomonas spp., 31 isolates from plants and 17 from insects, from different geographic regions. Topology of the dendrogram based on randomly amplified polymorphic DNA fingerprints segregated the Phytomonas spp. into 5 main clusters, despite the high genetic variability within this genus. Similar clustering could also be obtained by both visual and cross-hybridization analysis of randomly amplified synapomorphic DNA fragments. There was some concordance between the genetic relationship of isolates and their plant tissue tropism. Moreover, Phytomonas spp. from plants and insects were grouped according to geographic origin, thus revealing a complex structure of this taxon comprising several clusters of very closely related organisms.

Phylogenetic relationships of German heavy draught horse breeds inferred from mitochondrial DNA D-loop variation.

PubMed

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.

Association between mitochondrial DNA variations and schizophrenia in the northern Chinese Han population.

PubMed

Xu, Feng-Ling; Ding, Mei; Yao, Jun; Shi, Zhang-Sen; Wu, Xue; Zhang, Jing-Jing; Pang, Hao; Xing, Jia-Xin; Xuan, Jin-Feng; Wang, Bao-Jie

2017-01-01

To determine whether mitochondrial DNA (mtDNA) variations are associated with schizophrenia, 313 patients with schizophrenia and 326 unaffected participants of the northern Chinese Han population were included in a prospective study. Single-nucleotide polymorphisms (SNPs) including C5178A, A10398G, G13708A, and C13928G were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Hypervariable regions I and II (HVSI and HVSII) were analyzed by sequencing. The results showed that the 4 SNPs and 11 haplotypes, composed of the 4 SNPs, did not differ significantly between patient and control groups. No significant association between haplogroups and the risk of schizophrenia was ascertained after Bonferroni correction. Drawing a conclusion, there was no evidence of an association between mtDNA (the 4 SNPs and the control region) and schizophrenia in the northern Chinese Han population.

Ex vivo study for the assessment of behavioral factor and gene polymorphisms in individual susceptibility to oxidative DNA damage metals-induced.

PubMed

Di Pietro, Angela; Baluce, Barbara; Visalli, Giuseppa; La Maestra, Sebastiano; Micale, Rosanna; Izzotti, Alberto

2011-06-01

Transition metals in fine particulate matter generated by combustion induce oxidative DNA damage and inflammation. However, there is remarkable inter-individual variability in susceptibility to these damages. To assess this variability, an ex vivo study was performed using lymphocytes of 47 Caucasian healthy subjects. Cell samples were exposed to a water solution of oil fly ash (OFA). This was formed by the distinctive transition metals vanadium, iron, and nickel. Oxidative DNA damage was evaluated by testing cell viability, intracellular ROS production and 8-oxo-dG. DNA fragmentation and DNA repair capacity were assessed by using the Alkaline-Halo assay. GSTM1, GSTT1, hOGG1, and C677T and A1298C MTHFR gene polymorphisms were tested. Demographic and behavioral factors, collected by questionnaire, were also considered. OFA induced damages showed: (a) a 20-fold variation in range among different subjects in ROS production, (b) a 7-fold variation in range of 8-oxo-dG, and (c) a 25-fold variation in range in DNA repair capacity. A significant increase in DNA damage was detected in GSTT1-deficent subjects compared with wild type genotype carriers. Increases in cytoplasmic ROS and decreases in DNA repair capacity (P<0.05) were observed in C677T and A1298C variants of MTHFR. A remarkable protective effect of high fruits and vegetable intake was observed for ROS production and DNA damage. Conversely, an adverse effect of meat intake was observed on ROS increase, DNA damage and repair capacity, probably due to the increased intake of bioavailable iron. Smoking decreased DNA repair capacity, while age increased OFA-induced DNA damage. The wide comparative analysis of the complex interactions network, between genetic and behavioral factors provides evidence of the remarkable role of several lifestyle factors. In comparison to genetic polymorphisms they seem to have a higher weight in determining individual susceptibility to the adverse effects of airborne pollutants as transition metals. Copyright © 2011 Elsevier GmbH. All rights reserved.

DNA polymorphism sensitive impedimetric detection on gold-nanoislands modified electrodes.

PubMed

Bonanni, Alessandra; Pividori, Maria Isabel; del Valle, Manel

2015-05-01

Nanocomposite materials are being increasingly used in biosensing applications as they can significantly improve biosensor performance. Here we report the use of a novel impedimetric genosensor based on gold nanoparticles graphite-epoxy nanocomposite (nanoAu-GEC) for the detection of triple base mutation deletion in a cystic-fibrosis (CF) related human DNA sequence. The developed platform consists of chemisorbing gold nano-islands surrounded by rigid, non-chemisorbing, and conducting graphite-epoxy composite. The ratio of the gold nanoparticles in the composite was carefully optimized by electrochemical and microscopy studies. Such platform allows the very fast and stable thiol immobilization of DNA probes on the gold islands, thus minimizing the steric and electrostatic repulsion among the DNA probes and improving the detection of DNA polymorphism down to 2.25fmol by using electrochemical impedance spectroscopy. These findings are very important in order to develop new and renewable platforms to be used in point-of-care devices for the detection of biomolecules. Copyright © 2015 Elsevier B.V. All rights reserved.

SNPs in DNA repair or oxidative stress genes and late subcutaneous fibrosis in patients following single shot partial breast irradiation

PubMed Central

2012-01-01

Background The aim of this study was to evaluate the potential association between single nucleotide polymorphisms related response to radiotherapy injury, such as genes related to DNA repair or enzymes involved in anti-oxidative activities. The paper aims to identify marker genes able to predict an increased risk of late toxicity studying our group of patients who underwent a Single Shot 3D-CRT PBI (SSPBI) after BCS (breast conserving surgery). Methods A total of 57 breast cancer patients who underwent SSPBI were genotyped for SNPs (single nucleotide polymorphisms) in XRCC1, XRCC3, GST and RAD51 by Pyrosequencing technology. Univariate analysis (ORs and 95% CI) was performed to correlate SNPs with the risk of developing ≥ G2 fibrosis or fat necrosis. Results A higher significant risk of developing ≥ G2 fibrosis or fat necrosis in patients with: polymorphic variant GSTP1 (Ile105Val) (OR = 2.9; 95%CI, 0.88-10.14, p = 0.047). Conclusions The presence of some SNPs involved in DNA repair or response to oxidative stress seem to be able to predict late toxicity. Trial Registration ClinicalTrials.gov: NCT01316328 PMID:22272830

Polymorphic Variation in Double Strand Break Repair Gene in Indian Population: A Comparative Approach with Worldwide Ethnic Group Variations.

PubMed

Mandal, Raju Kumar; Mittal, Rama Devi

2018-04-01

DNA repair capacity is essential in maintaining cellular functions and homeostasis. Identification of genetic polymorphisms responsible for reduced DNA repair capacity may allow better cancer prevention. Double strand break repair pathway plays critical roles in maintaining genome stability. Present study was conducted to determine distribution of XRCC3 Exon 7 (C18067T, rs861539) and XRCC7 Intron 8 (G6721T, rs7003908) gene polymorphisms in North Indian population and compare with different populations globally. The genotype assays were performed in 224 normal healthy individuals of similar ethnicity using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Allelic frequencies of wild type were 79% (C) in XRCC3 Exon 7 C > T and 57% (G) in XRCC7 Intron 8 (G > T) 57% (G) observed. On the other hand, the variant allele frequency were 21% (T) in XRCC3 Exon 7 C > T and 43% (T) in XRCC7 Intron 8 G > T respectively. Major differences from other ethnic populations were observed. Our results suggest that frequency in these DNA repair genes exhibit distinctive pattern in India that could be attributed to ethnicity variation. This could assist in high-risk screening of humans exposed to environmental carcinogens and cancer predisposition in different ethnic groups.

Haplotype data for 23 Y-chromosome markers in a reference sample from Bosnia and Herzegovina.

PubMed

Kovačević, Lejla; Fatur-Cerić, Vera; Hadzic, Negra; Čakar, Jasmina; Primorac, Dragan; Marjanović, Damir

2013-06-01

To detect polymorphisms of 23 Y-chromosomal short tandem repeat (STR) loci, including 6 new loci, in a reference database of male population of Bosnia and Herzegovina, as well as to assess the importance of increasing the number of Y-STR loci utilized in forensic DNA analysis. The reference sample consisted of 100 healthy, unrelated men originating from Bosnia and Herzegovina. Sample collection using buccal swabs was performed in all geographical regions of Bosnia and Herzegovina in the period from 2010 to 2011. DNA samples were typed for 23 Y STR loci, including 6 new loci: DYS576, DYS481, DYS549, DYS533, DYS570, and DYS643, which are included in the new PowerPlex® Y 23 amplification kit. The absolute frequency of generated haplotypes was calculated and results showed that 98 samples had unique Y 23 haplotypes, and that only two samples shared the same haplotype. The most polymorphic locus was DYS418, with 14 detected alleles and the least polymorphic loci were DYS389I, DYS391, DYS437, and DYS393. This study showed that by increasing the number of highly polymorphic Y STR markers, to include those tested in our analysis, leads to a reduction of repeating haplotypes, which is very important in the application of forensic DNA analysis.

Cloning of soluble alkaline phosphatase cDNA and molecular basis of the polymorphic nature in alkaline phosphatase isozymes of Bombyx mori midgut.

PubMed

Itoh, M; Kanamori, Y; Takao, M; Eguchi, M

1999-02-01

A cDNA coding for soluble type alkaline phosphatase (sALP) of Bombyx mori was isolated. Deduced amino acid sequence showed high identities to various ALPs and partial similarities to ATPase of Manduca sexta. Using this cDNA sequence as a probe, the molecular basis of electrophoretic polymorphism in sALP and membrane-bound type ALP (mALP) was studied. As for mALP, the result suggested that post-translational modification was important for the proteins to express activity and to represent their extensive polymorphic nature, whereas the magnitude of activities was mainly regulated by transcription. On the other hand, sALP zymogram showed poor polymorphism, but one exception was the null mutant, in which the sALP gene was largely lost. Interestingly, the sALP gene was shown to be transcribed into two mRNAs of different sizes, 2.0 and 2.4 Kb. In addition to the null mutant of sALP, we found a null mutant for mALP. Both of these mutants seem phenotypically silent, suggesting that the functional differentiation between these isozymes is not perfect, so that they can still work mutually and complement each other as an indispensable enzyme for B. mori.

Extensive mitochondrial heteroplasmy in the neotropical ants of the Ectatomma ruidum complex (Formicidae: Ectatomminae)

USDA-ARS?s Scientific Manuscript database

Recent advances in DNA sequencing and polymorphism detection technology have made it possible to test for the existence of more than one type of organellar genome within a cell or individual (heteroplasmy). Here we investigated whether the origin of mitochondrial (mt) DNA polymorphism in members of ...

Single nucleotide polymorphisms in uracil-processing genes, intake of one-carbon nutrients and breast cancer risk

USDA-ARS?s Scientific Manuscript database

Background/Objectives: The misincorporation of uracil into DNA leads to genomic instability. In a previous study, some of us identified four common single nucleotide polymorphisms (SNPs) in uracil-processing genes (rs2029166 and rs7296239 in SMUG1, rs34259 in UNG and rs4775748 in DUT) that were asso...

Role of genetic polymorphisms of CYP1A1, CYP3A5, CYP2C9, CYP2D6, and PON1 in the modulation of DNA damage in workers occupationally exposed to organophosphate pesticides

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

Singh, Satyender; Kumar, Vivek; Vashisht, Kapil

2011-11-15

Organophosphate pesticides (OPs) are primarily metabolized by several xenobiotic metabolizing enzymes (XMEs). Very few studies have explored genetic polymorphisms of XMEs and their association with DNA damage in pesticide-exposed workers. The present study was designed to determine the role of genetic polymorphisms of CYP1A1, CYP3A5, CYP2C9, CYP2D6, and PON1 in the modulation of DNA damage in workers occupationally exposed to OPs. We examined 284 subjects including 150 workers occupationally exposed to OPs and 134 normal healthy controls. The DNA damage was evaluated using the alkaline comet assay and genotyping was done using PCR-RFLP. The results revealed that the PONase activitymore » toward paraoxonase and AChE activity was found significantly lowered in workers as compared to control subjects (p < 0.001). Workers showed significantly higher DNA damage compared to control subjects (14.37 {+-} 2.15 vs. 6.24 {+-} 1.37 tail% DNA, p < 0.001). Further, the workers with CYP2D6*3 PM and PON1 (QQ and MM) genotypes were found to have significantly higher DNA damage when compared to other genotypes (p < 0.05). In addition, significant increase in DNA damage was also observed in workers with concomitant presence of certain CYP2D6 and PON1 (Q192R and L55M) genotypes which need further extensive studies. In conclusion, the results indicate that the PON1 and CYP2D6 genotypes can modulate DNA damage elicited by some OPs possibly through gene-environment interactions. -- Highlights: Black-Right-Pointing-Pointer Role of CYP1A1, CYP3A5, CYP2C, CYP2D6 and PON1 genotypes on DNA damage. Black-Right-Pointing-Pointer Workers exposed to some OPs demonstrated increased DNA damage. Black-Right-Pointing-Pointer CYP2D6 *3 PM and PON1 (Q192R and L55M) genotypes are associated with DNA damage. Black-Right-Pointing-Pointer Concomitant presence of certain CYP2D6 and PON1 genotypes can increase DNA damage.« less

Association of the methylenetetrahydrofolate reductase polymorphism in Korean patients with childhood acute lymphoblastic leukemia.

PubMed

Kim, Nam Keun; Chong, So Young; Jang, Moon Ju; Hong, Seung Ho; Kim, Heung Sik; Cho, Eun Kyung; Lee, Jung Ae; Ahn, Myung Ju; Kim, Chul Soo; Oh, Doyeun

2006-01-01

Methylenetetrahydrofolate reductase plays a central role in converting folate to methyl donor for DNA methylation. Recently, methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) mutations were discovered to be associated with childhood acute lymphoblastic leukemia (ALL), as well as colon cancer, lymphoma, esophageal and stomach cancer. Therefore, it was hypothesized that the MTHFR polymorphisms are associated with the risk of childhood ALL in the Korean population. DNA samples taken from 66 patients with ALL and 100 age-matched controls were analyzed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay for detection of MTHFR C677T and A1298C mutations. The frequency of the AC genotype for MTHFR A1298C polymorphism was significantly different between the controls and the cases (OR, 2.22; CI, 95% 1.09-4.51, p=0.03). The 1298AC+CC genotype was also significantly different (OR, 2.11; 95% CI, 1.06-4.22; p=0.049). There was, however, no significant difference for MTHFR C677T polymorphism and combined genotype frequencies between the two groups. Although no consistent results on associations between MTHFR A 1298C polymorphism and ALL in the populations studied were obtained, the A1298C polymorphism, at least in Koreans, may be a genetic determinant among childhood ALL patients.

DNA methylation changes detected by methylation-sensitive amplified polymorphism in two contrasting rice genotypes under salt stress.

PubMed

Wang, Wensheng; Zhao, Xiuqin; Pan, Yajiao; Zhu, Linghua; Fu, Binying; Li, Zhikang

2011-09-20

DNA methylation, one of the most important epigenetic phenomena, plays a vital role in tuning gene expression during plant development as well as in response to environmental stimuli. In the present study, a methylation-sensitive amplified polymorphism (MSAP) analysis was performed to profile DNA methylation changes in two contrasting rice genotypes under salt stress. Consistent with visibly different phenotypes in response to salt stress, epigenetic markers classified as stable inter-cultivar DNA methylation differences were determined between salt-tolerant FL478 and salt-sensitive IR29. In addition, most tissue-specific DNA methylation loci were conserved, while many of the growth stage-dependent DNA methylation loci were dynamic between the two genotypes. Strikingly, salt stress induced a decrease in DNA methylation specifically in roots at the seedling stage that was more profound in IR29 than in the FL478. This result may indicate that demethylation of genes is an active epigenetic response to salt stress in roots at the seedling stage, and helps to further elucidate the implications of DNA methylation in crop growth and development. Copyright © 2011. Published by Elsevier Ltd.

MTHFR GENE C677T POLYMORPHISM AND LEVELS OF DNA METHYLTRASFERASES IN SUBCLINICAL HYPOTHYROIDISM.

PubMed

Kvaratskhelia, T; Kvaratskhelia, E; Kankava, K; Abzianidze, E

2017-04-01

The aim of our study was to investigate the link between MTHFR gene C677T polymorphism and DNMTs levels in patients with Subclinical Hypothyroidism (SCH). In this study 19 adult patients with subclinical hypothyroidism and 19 healthy controls (mean age 31±5.5 and 33±5.1 years respectively) were recruited. All patients were diagnosed based on serum levels of TSH, FT4, anti-TG and anti-TPO antibodies. Written informed consents were obtained from all study subjects. Genomic DNA was extracted using Quick-DNA Universal Kit (Zymo Research, USA). The MTHFR C677T polymorphism was genotyped by PCR-RFLP method. Levels of DNMT1 and 3a were measured in nuclear extracts of PBMC using DNMTs assay kits (Abcam). Our data indicates that the frequency of genotypes and alleles were different among the patient and the control group. There is a significant increase in CC genotype distribution in the control group when compared to the SCH patient group, while the CT as well as TT genotype distribution were not increased significantly in SCH group versus control group. However the C allele is significantly prevalent in the control group compared to the SCH group, while T allele is prevalent in patients compared to the control group with a statically significant difference. In addition, individuals with TT and CT genotypes and hypothyroidism showed elevated amount of DNMT3a in nuclear extracts of PBMC compared with controls, while no significant difference in DNMT1 levels was observed. This study indicates the MTHFR C677T variant may contribute in alteration of epigenetic regulation such as DNA methylation mediated by DNA methyltransferases in patients with subclinical hypothyroidism and also, carriers of the T allele might have an increasing risk of developing SCH.

[Effect of mitochondrial DNA 5178 C/A polymorphism on risks for type 2 diabetes mellitus and its complications].

PubMed

Yang, Xunjun; Zhang, Yuning; Ma, Yin; Zhao, Qiongya; Lyu, Jianxin

2015-12-01

To explore the role of mitochondrial DNA 5178 C/A (Mt5178) polymorphism of NADH-dehydrogenase subunit 2 (ND2) gene in type-2 diabetes mellitus (T2DM) among ethnic Han Chinese through a case-control study. The Mt5178C/A polymorphism was determined by sequencing 1103 T2DM patients and 791 healthy controls. Logistic regression analysis was conducted to estimate odds ratios (OR) and 95% confidence intervals (CI). To confirm the results, a meta-analysis was conducted based on published literature on the association of Mt5178 variant with T2DM. No significant association was found between the Mt5178C/A variant and T2DM either by our study or the meta-analysis which included eight published studies. Nevertheless, it was found that the T2DM patients with 5178C genotype were at a higher risk for nephropathy complication (OR=1.49, 95%CI: 1.005-2.197, P<0.05) and at significantly lower risk for hypertension complication (OR=0.744, 95%CI: 0.556-0.996, P<0.05) compared with those carrying a 5178A genotype. No association was found between the Mt5178C/A polymorphism of mitochondrial ND2 gene with the increased risk of T2DM. However, the polymorphism may affect the development of nephropathy and hypertension complications among T2DM patients.

Chromosomal distribution of pTa-535, pTa-86, pTa-713, 35S rDNA repetitive sequences in interspecific hexaploid hybrids of common wheat (Triticum aestivum L.) and spelt (Triticum spelta L.)

PubMed Central

Duba, Adrian; Kwiatek, Michał; Wiśniewska, Halina; Wachowska, Urszula; Wiwart, Marian

2018-01-01

Fluorescent in situ hybridization (FISH) relies on fluorescent-labeled probes to detect specific DNA sequences in the genome, and it is widely used in cytogenetic analyses. The aim of this study was to determine the karyotype of T. aestivum and T. spelta hybrids and their parental components (three common wheat cultivars and five spelt breeding lines), to identify chromosomal aberrations in the evaluated wheat lines, and to analyze the distribution of polymorphisms of repetitive sequences in the examined hybrids. The FISH procedure was carried out with four DNA clones, pTa-86, pTa-535, pTa-713 and 35S rDNA used as probes. The observed polymorphisms between the investigated lines of common wheat, spelt and their hybrids was relatively low. However, differences were observed in the distribution of repetitive sequences on chromosomes 4A, 6A, 1B and 6B in selected hybrid genomes. The polymorphisms observed in common wheat and spelt hybrids carry valuable information for wheat breeders. The results of our study are also a valuable source of knowledge about genome organization and diversification in common wheat, spelt and their hybrids. The relevant information is essential for common wheat breeders, and it can contribute to breeding programs aimed at biodiversity preservation. PMID:29447228

Chromosomal distribution of pTa-535, pTa-86, pTa-713, 35S rDNA repetitive sequences in interspecific hexaploid hybrids of common wheat (Triticum aestivum L.) and spelt (Triticum spelta L.).

PubMed

Goriewa-Duba, Klaudia; Duba, Adrian; Kwiatek, Michał; Wiśniewska, Halina; Wachowska, Urszula; Wiwart, Marian

2018-01-01

Fluorescent in situ hybridization (FISH) relies on fluorescent-labeled probes to detect specific DNA sequences in the genome, and it is widely used in cytogenetic analyses. The aim of this study was to determine the karyotype of T. aestivum and T. spelta hybrids and their parental components (three common wheat cultivars and five spelt breeding lines), to identify chromosomal aberrations in the evaluated wheat lines, and to analyze the distribution of polymorphisms of repetitive sequences in the examined hybrids. The FISH procedure was carried out with four DNA clones, pTa-86, pTa-535, pTa-713 and 35S rDNA used as probes. The observed polymorphisms between the investigated lines of common wheat, spelt and their hybrids was relatively low. However, differences were observed in the distribution of repetitive sequences on chromosomes 4A, 6A, 1B and 6B in selected hybrid genomes. The polymorphisms observed in common wheat and spelt hybrids carry valuable information for wheat breeders. The results of our study are also a valuable source of knowledge about genome organization and diversification in common wheat, spelt and their hybrids. The relevant information is essential for common wheat breeders, and it can contribute to breeding programs aimed at biodiversity preservation.

Association study between XRCC1 gene polymorphisms and sporadic amyotrophic lateral sclerosis.

PubMed

Coppedè, Fabio; Migheli, Francesca; Lo Gerfo, Annalisa; Fabbrizi, Maria Rita; Carlesi, Cecilia; Mancuso, Michelangelo; Corti, Stefania; Mezzina, Nicoletta; del Bo, Roberto; Comi, Giacomo P; Siciliano, Gabriele; Migliore, Lucia

2010-01-01

The aim of the present study was to investigate the possible contribution of three common functional polymorphisms in the DNA repair protein X-ray repair cross-complementing group 1 (XRCC1), namely Arg194Trp (rs1799782), Arg280His (rs25489) and Arg399Gln (rs25487), to sporadic amyotrophic lateral sclerosis (SALS). We genotyped 206 Italian SALS patients and 203 matched controls for XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphisms by means of PCR/RFLP technique, searching for association between any of the studied polymorphisms and disease risk, age and site of onset. We observed a statistically significant difference in XRCC1 Gln399 allele frequencies between SALS cases and controls (0.39/0.28; p=0.001). The present study suggests that the XRCC1 Arg399Gln polymorphism might contribute to SALS risk.

Sex Determination from Fragmented and Degenerated DNA by Amplified Product-Length Polymorphism Bidirectional SNP Analysis of Amelogenin and SRY Genes.

PubMed

Masuyama, Kotoka; Shojo, Hideki; Nakanishi, Hiroaki; Inokuchi, Shota; Adachi, Noboru

2017-01-01

Sex determination is important in archeology and anthropology for the study of past societies, cultures, and human activities. Sex determination is also one of the most important components of individual identification in criminal investigations. We developed a new method of sex determination by detecting a single-nucleotide polymorphism in the amelogenin gene using amplified product-length polymorphisms in combination with sex-determining region Y analysis. We particularly focused on the most common types of postmortem DNA damage in ancient and forensic samples: fragmentation and nucleotide modification resulting from deamination. Amplicon size was designed to be less than 60 bp to make the method more useful for analyzing degraded DNA samples. All DNA samples collected from eight Japanese individuals (four male, four female) were evaluated correctly using our method. The detection limit for accurate sex determination was determined to be 20 pg of DNA. We compared our new method with commercial short tandem repeat analysis kits using DNA samples artificially fragmented by ultraviolet irradiation. Our novel method was the most robust for highly fragmented DNA samples. To deal with allelic dropout resulting from deamination, we adopted "bidirectional analysis," which analyzed samples from both sense and antisense strands. This new method was applied to 14 Jomon individuals (3500-year-old bone samples) whose sex had been identified morphologically. We could correctly identify the sex of 11 out of 14 individuals. These results show that our method is reliable for the sex determination of highly degenerated samples.

Sex Determination from Fragmented and Degenerated DNA by Amplified Product-Length Polymorphism Bidirectional SNP Analysis of Amelogenin and SRY Genes

PubMed Central

Masuyama, Kotoka; Shojo, Hideki; Nakanishi, Hiroaki; Inokuchi, Shota; Adachi, Noboru

2017-01-01

Sex determination is important in archeology and anthropology for the study of past societies, cultures, and human activities. Sex determination is also one of the most important components of individual identification in criminal investigations. We developed a new method of sex determination by detecting a single-nucleotide polymorphism in the amelogenin gene using amplified product-length polymorphisms in combination with sex-determining region Y analysis. We particularly focused on the most common types of postmortem DNA damage in ancient and forensic samples: fragmentation and nucleotide modification resulting from deamination. Amplicon size was designed to be less than 60 bp to make the method more useful for analyzing degraded DNA samples. All DNA samples collected from eight Japanese individuals (four male, four female) were evaluated correctly using our method. The detection limit for accurate sex determination was determined to be 20 pg of DNA. We compared our new method with commercial short tandem repeat analysis kits using DNA samples artificially fragmented by ultraviolet irradiation. Our novel method was the most robust for highly fragmented DNA samples. To deal with allelic dropout resulting from deamination, we adopted “bidirectional analysis,” which analyzed samples from both sense and antisense strands. This new method was applied to 14 Jomon individuals (3500-year-old bone samples) whose sex had been identified morphologically. We could correctly identify the sex of 11 out of 14 individuals. These results show that our method is reliable for the sex determination of highly degenerated samples. PMID:28052096

Specific Polymorphic Variation in the Mitochondrial Genome and Increased In-Hospital Mortality After Severe Trauma

PubMed Central

Canter, Jeffrey A.; Norris, Patrick R.; Moore, Jason H.; Jenkins, Judith M.; Morris, John A.

2007-01-01

Objective: To determine whether specific genetic variations in the mtDNA that impact energy production and free-radical generation are potential new risk factors for in-hospital mortality after severe trauma. Summary Background Data: Each of the 3 mitochondrial DNA polymorphisms selected for this study (at positions 4216, 10398, 4917) alter the amino acid sequence of different key subunits of Complex I in the electron transport chain. They have been previously implicated in phenotypes involving tissues with high-energy demand, such as the brain and retina. Methods: Seven hundred forty-five consecutive patients admitted to the trauma intensive care unit at Vanderbilt University Medical Center between April 11, 2005, and February 27, 2006, were potentially eligible for this study. Under an Institutional Review Board-approved protocol (which excluded patients <18 years of age and prisoners), 666 patients had DNA extracted from a blood sample. Detailed demographic and clinical covariates were also obtained (including age, gender, ethnicity, lactate measurements, and injury severity score). A flurogenic 5′ nuclease allelic discrimination Taqman assay and the ABI 7900HT Sequence Detection System (v2.1) was used to genotype the T4216C, A10398G, and A4917G polymorphisms. The primary outcome was in-hospital mortality. Results: Multivariate logistic regression analysis revealed that the 4216T allele was a significant independent predictor of in-hospital mortality (OR = 2.63, 95% CI 1.14–6.07, P = 0.02) after adjustment for age, gender, injury severity score, highest lactate level, mechanism of injury, and the 10398 polymorphism. Conclusions: Variation in the mtDNA, specifically the 4216T allele, appears to increase the risk of in-hospital mortality after severe injury. PMID:17717444

Surveyor nuclease detection of mutations and polymorphisms of mtDNA in children.

PubMed

Pilch, Jacek; Asman, Marek; Jamroz, Ewa; Kajor, Maciej; Kotrys-Puchalska, Elżbieta; Goss, Małgorzata; Krzak, Maria; Witecka, Joanna; Gmiński, Jan; Sieroń, Aleksander L

2010-11-01

Mitochondrial encephalomyopathies are complex disorders with wide range of clinical manifestations. Particularly time-consuming is the identification of mutations in mitochondrial DNA. A group of 20 children with clinical manifestations of mitochondrial encephalomyopathies was selected for molecular studies. The aims were (a) to identify mutations in mtDNA isolated from muscle and (b) to verify detected mutations in DNA isolated from blood, in order to assess the utility of a Surveyor nuclease assay kit for patient screening. The most common changes found were polymorphisms, including a few missense mutations altering the amino acid sequence of mitochondrial proteins. In two boys with MELAS (i.e., mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes), a mutation A→G3243 was detected in the tRNALeu gene of mtDNA isolated from muscle and blood. In one boy, the carrier status of his mother was confirmed, based on molecular analysis of DNA isolated from blood. A method using Surveyor nuclease allows systematic screening for small mutations in mtDNA, using as its source blood of the patients and asymptomatic carriers. The method still requires confirmation studying a larger group. In some patients, the use of this method should precede and might limit indications for traumatic muscle and skin biopsy. Copyright © 2010 Elsevier Inc. All rights reserved.

Genetic variation and epigenetic modification of the prodynorphin gene in peripheral blood cells in alcoholism.

PubMed

D'Addario, Claudio; Shchetynsky, Klementy; Pucci, Mariangela; Cifani, Carlo; Gunnar, Agneta; Vukojević, Vladana; Padyukov, Leonid; Terenius, Lars

2017-06-02

Dynorphins are critically involved in the development, maintenance and relapse of alcoholism. Alcohol-induced changes in the prodynorphin gene expression may be influenced by both gene polymorphisms and epigenetic modifications. The present study of human alcoholics aims to evaluate DNA methylation patterns in the prodynorphin gene (PDYN) promoter and to identify single nucleotide polymorphisms (SNPs) associated with alcohol dependence and with altered DNA methylation. Genomic DNA was isolated from peripheral blood cells of alcoholics and healthy controls, and DNA methylation was studied in the PDYN promoter by bisulfite pyrosequencing. In alcoholics, DNA methylation increased in three of the seven CpG sites investigated, as well as in the average of the seven CpG sites. Data stratification showed lower increase in DNA methylation levels in individuals reporting craving and with higher levels of alcohol consumption. Association with alcoholism was observed for rs2235751 and the presence of the minor allele G was associated with reduced DNA methylation at PDYN promoter in females and younger subjects. Genetic and epigenetic factors within PDYN are related to risk for alcoholism, providing further evidence of its involvement on ethanol effects. These results might be of relevance for developing new biomarkers to predict disease trajectories and therapeutic outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

[Paternity study in Chilean families using DNA fingerprints and erythrocyte blood markers].

PubMed

Aguirre, R; Blanco, R; Cifuentes, L; Chiffelle, I; Armanet, L; Vargas, J; Jara, L

1992-10-01

In the last decade, the electromorphic phenotype corresponding to extremely polymorphic zones of DNA, that include variable number of tandem repeat loci (VNTR) of oligonucleotide sequences, have been added to classical markers to elucidate the problems of parenthood identification and ascription in human beings. Using VNTR of several loci, a band profile practically unique for each individual is obtained (DNA-fingerprints). Since the pattern of VNTR electrophoretic bands is inherited from parents in a proportion of 50% from each one, this system is extremely useful for paternity ascription or exclusion. Nine nuclear families were studied, randomly selected from a group of 170 families that were analyzed using 5 erythrocyte genetic markers and with VNTRs detected using the multi locus probe (CAC)5, aiming to explore the concordance of both methods. Results were similar for both methods; however for VNTR, there is no information available on population frequency of polymorphisms.

DNA methylation and genome rearrangement characteristics of phase change in cultured shoots of Sequoia sempervirens.

PubMed

Huang, Li-Chun; Hsiao, Lin-June; Pu, Szu-Yuan; Kuo, Ching-I; Huang, Bau-Lian; Tseng, Tsung-Che; Huang, Hao-Jen; Chen, Yu-Ting

2012-06-01

Epigenetic machinery regulates the expression of individual genes and plays a crucial role in globally shaping and maintaining developmental patterning. We studied the extent of DNA methylation in the nucleus, mitochondrion and chloroplast in cultured Sequoia sempervirens (coast redwood) adult, juvenile and rejuvenated shoots by measuring the ratio of methylcytosine to total cytosine using high-performance liquid chromatography (HPLC). We also analyzed nuclear DNA (nuDNA) polymorphisms of different shoot types by methylation-sensitive amplified fragment length polymorphism (MSAP) and Southern blot analysis. The extent of nuDNA methylation was greater in the adult vegetative than juvenile and rejuvenated shoots (8% vs 6.5-7.5%). In contrast, the proportion of methylcytosine was higher in mitochondrial DNA (mDNA) of juvenile and rejuvenated shoots than adult shoots (6.6% vs 7.8-8.2%). MSAP and Southern blot analyses identified three MSAP fragments which could be applied as phase-specific molecular markers. We also found nuclear genome and mtDNA rearrangement may be as important as DNA methylation status during the phase change. Our findings strongly suggest that DNA methylation and genome rearrangement may affect the dynamic tissue- and cell type-specific changes that determine the developmental phase of S. sempervirens shoots. Copyright © Physiologia Plantarum 2012.

Differential DNA Methylation Patterns Are Related to Phellogen Origin and Quality of Quercus suber Cork.

PubMed

Inácio, Vera; Barros, Pedro M; Costa, Augusta; Roussado, Cristóvão; Gonçalves, Elsa; Costa, Rita; Graça, José; Oliveira, M Margarida; Morais-Cecílio, Leonor

2017-01-01

DNA methylation is thought to influence Quercus suber cork quality, which is the main constraint for its economic valorisation. However, a deep knowledge of the cytosine methylation patterns disclosing the epigenetic variability of trees with different cork quality types is totally missing. This study investigates the hypothesis that variations in DNA methylation contribute to differences in cork cellular characteristics directly related to original or traumatic phellogen activity. We used MSAPs (Methylation Sensitive Amplified Polymorphism) to assess DNA methylation patterns of cork and leaf tissues of Q. suber adult trees growing in three cork oak stands. The relationship between the detected polymorphisms and the diversity of cork quality traits was explored by a marker-trait analysis focusing on the most relevant quality characteristics. Populations differed widely in cork quality, but only slightly in degree of epigenetic differentiation. Four MSAP markers (1.3% of the total) were significantly associated with the most noteworthy quality traits: wood inclusions (nails) and porosity. This evidence supports the potential role of cytosine methylation in the modulation of differential phellogen activity either involved in localized cell death or in pore production, resulting in different cork qualities. Although, the underlying basis of the methylation polymorphism of loci affecting cork quality traits remain unclear, the disclosure of markers statistically associated with cork quality strengthens the potential role of DNA methylation in the regulation of these traits, namely at the phellogen level.

Polymorphism in xeroderma pigmentosum complementation group C codon 939 and aflatoxin B1-related hepatocellular carcinoma in the Guangxi population.

PubMed

Long, Xi-Dai; Ma, Yun; Zhou, Yuan-Feng; Ma, Ai-Min; Fu, Guo-Hui

2010-10-01

Genetic polymorphisms in DNA repair genes may influence individual variations in DNA repair capacity, and this may be associated with the risk and outcome of hepatocellular carcinoma (HCC) related to aflatoxin B1 (AFB1) exposure. In this study, we focused on the polymorphism of xeroderma pigmentosum complementation group C (XPC) codon 939 (rs#2228001), which is involved in nucleotide excision repair. We conducted a case-control study including 1156 HCC cases and 1402 controls without any evidence of hepatic disease to evaluate the associations between this polymorphism and HCC risk and prognosis in the Guangxi population. AFB1 DNA adduct levels, XPC genotypes, and XPC protein levels were tested with a comparative enzyme-linked immunosorbent assay, TaqMan polymerase chain reaction for XPC genotypes, and immunohistochemistry, respectively. Higher AFB1 exposure was observed among HCC patients versus the control group [odds ratio (OR) = 9.88 for AFB1 exposure years and OR = 6.58 for AFB1 exposure levels]. The XPC codon 939 Gln alleles significantly increased HCC risk [OR = 1.25 (95% confidence interval = 1.03-1.52) for heterozygotes of the XPC codon 939 Lys and Gln alleles (XPC-LG) and OR = 1.81 (95% confidence interval = 1.36-2.40) for homozygotes of the XPC codon 939 Gln alleles (XPC-GG)]. Significant interactive effects between genotypes and AFB1 exposure status were also observed in the joint-effects analysis. This polymorphism, moreover, was correlated with XPC expression levels in cancerous tissues (r = -0.369, P < 0.001) and with the overall survival of HCC patients (the median survival times were 30, 25, and 19 months for patients with homozygotes of the XPC codon 939 Lys alleles, XPC-LG, and XPC-GG, respectively), especially under high AFB1 exposure conditions. Like AFB1 exposure, the XPC codon 939 polymorphism was an independent prognostic factor influencing the survival of HCC. Additionally, this polymorphism multiplicatively interacted with the xeroderma pigmentosum complementation group D codon 751 polymorphism with respect to HCC risk (OR(interaction) = 1.71). These results suggest that the XPC codon 939 polymorphism may be associated with the risk and outcome of AFB1-related HCC in the Guangxi population and may interact with AFB1 exposure in the process of HCC induction by AFB1.

DNA damage and oxidative stress response to selenium yeast in the non-smoking individuals: a short-term supplementation trial with respect to GPX1 and SEPP1 polymorphism.

PubMed

Jablonska, E; Raimondi, S; Gromadzinska, J; Reszka, E; Wieczorek, E; Krol, M B; Smok-Pieniazek, A; Nocun, M; Stepnik, M; Socha, K; Borawska, M H; Wasowicz, W

2016-12-01

Selenium, both essential and toxic element, is considered to protect against cancer, though human supplementation trials have generated many inconsistent data. Genetic background may partially explain a great variability of the studies related to selenium and human health. The aim of this study was to assess whether functional polymorphisms within two selenoprotein-encoding genes modify the response to selenium at the level of oxidative stress, DNA damage, and mRNA expression, especially in the individuals with a relatively low selenium status. The trial involved 95 non-smoking individuals, stratified according to GPX1 rs1050450 and SEPP1 rs3877899 genotypes, and supplemented with selenium yeast (200 µg) for 6 weeks. Blood was collected at four time points, including 4 weeks of washout. After genotype stratification, the effect of GPX1 rs1050450 on lower GPx1 activity responsiveness was confirmed; however, in terms of DNA damage, we failed to indicate that individuals homozygous for variant allele may especially benefit from the increased selenium intake. Surprisingly, considering gene and time interaction, GPX1 polymorphism was observed to modify the level of DNA strand breaks during washout, showing a significant increase in GPX1 wild-type homozygotes. Regardless of the genotype, selenium supplementation was associated with a selectively suppressed selenoprotein mRNA expression and inconsistent changes in oxidative stress response, indicating for overlapped, antioxidant, and prooxidant effects. Intriguingly, DNA damage was not influenced by supplementation, but it was significantly increased during washout. These results point to an unclear relationship between selenium, genotype, and DNA damage.

Polymorphism in the DNA repair gene XPD, polycyclic aromatic hydrocarbon-DNA adducts, cigarette smoking, and breast cancer risk.

PubMed

Terry, Mary Beth; Gammon, Marilie D; Zhang, Fang Fang; Eng, Sybil M; Sagiv, Sharon K; Paykin, Andrea B; Wang, Qiao; Hayes, Sharon; Teitelbaum, Susan L; Neugut, Alfred I; Santella, Regina M

2004-12-01

DNA repair is essential to an individual's ability to respond to damage caused by environmental carcinogens. Alterations in DNA repair genes may affect cancer risk by influencing individual susceptibility to environmental exposures. XPD, a gene involved in nucleotide excision repair, may influence individual DNA repair capacity particularly of bulky adducts. Using a population-based breast cancer case-control study that was specifically conducted to examine markers of environmental exposures, such as polycyclic aromatic hydrocarbons (PAH), on Long Island, NY, we examined whether XPD genotype modified the associations among PAH-DNA adducts, cigarette smoking, and breast cancer risk. Specifically, we examined the XPD polymorphism at exon 23, position 751 in 1,053 breast cancer cases and 1,102 population-based controls. The presence of at least one variant allele (Lys/Gln or Gln/Gln) was associated with a 20% increase in risk of breast cancer [odds ratio (OR), 1.21; 95% confidence interval (95% CI), 1.01-1.44]. The increase in risk for homozygosity of the variant allele (Gln/Gln) seemed limited to those with PAH-DNA adduct levels above the median(OR, 1.61; 95% CI, 0.99-2.63 for adducts above the median versus OR, 1.05; 95% CI, 0.64-1.74 for adductsbelow the median), although the multiplicative interaction was not statistically significant. The increasein risk for homozygosity of the variant allele (Gln/Gln) was only seen among current smokers (OR, 1.97; 95% CI, 1.02-3.81 for current smokers versus OR, 0.87; 95% CI, 0.57-1.32 for never smokers); the multiplicative interaction was statistically significant. Overall, this study suggests that those individuals with this polymorphism in the XPD gene may face an increased risk of breast cancer from PAH-DNA adducts and cigarette smoking.

DNA sequence divergence among derivatives of Escherichia coli K-12 detected by arbitrary primer PCR (random amplified polymorphic DNA) fingerprinting.

PubMed Central

Brikun, I; Suziedelis, K; Berg, D E

1994-01-01

Derivatives of Escherichia coli K-12 of known ancestry were characterized by random amplified polymorphic DNA (RAPD) fingerprinting to better understand genome evolution in this family of closely related strains. This sensitive method entails PCR amplification with arbitrary primers at low stringency and yields arrays of anonymous DNA fragments that are strain specific. Among 150 fragments scored, eight were polymorphic in that they were produced from some but not all strains. Seven polymorphic bands were chromosomal, and one was from the F-factor plasmid. Five of the six mapped polymorphic chromosomal bands came from just 7% of the genome, a 340-kb segment that includes the terminus of replication. Two of these were from the cryptic Rac prophage, and the inability to amplify them from strains was attributable to deletion (excision) or to rearrangement of Rac. Two other terminus-region segments that resulted in polymorphic bands appeared to have sustained point mutations that affected the ability to amplify them. Control experiments showed that RAPD bands from the 340-kb terminus-region segment and also from two plasmids (P1 and F) were represented in approximate proportion to their size. Optimization experiments showed that the concentration of thermostable polymerase strongly affected the arrays of RAPD products obtained. Comparison of RAPD polymorphisms and positions of strains exhibiting them in the pedigree suggests that many sequence changes occurred in these historic E. coli strains during their storage. We propose that the clustering of such mutations near the terminus reflects errors during completion of chromosome replication, possibly during slow growth in the stab cultures that were often used to store E. coli strains in the early years of bacterial genetics. Images PMID:8132463

Mismatch repair gene MSH3 polymorphism is associated with the risk of sporadic prostate cancer

PubMed Central

Hirata, Hiroshi; Hinoda, Yuji; Kawamoto, Ken; Kikuno, Nobuyuki; Suehiro, Yutaka; Okayama, Naoko; Tanaka, Yuichiro; Dahiya, Rajvir

2014-01-01

Purpose The mismatch repair (MMR) system is a DNA repair mechanism that corrects mispaired bases during DNA replication errors. Cancer cells deficient in the MMR proteins have a 102 –103-fold increase in the mutation rate. Single nucleotide polymorphisms (SNPs) of MMR genes have been shown to cause a reduction in DNA repair activity. We hypothesized that mismatch repair gene polymorphism could be a risk factor for prostate cancer (PC) and that p53 Pro/Pro genotype carriers could influence MSH3 and MSH6 polymorphisms. Material and Methods DNA samples from 110 cases of prostate cancer and healthy controls (n=110) were analyzed by SSCP and PCR-RFLP to determine the genotypic frequency of five different polymorphic loci on two MMR genes (MSH3 and MSH6) and p53 codon72. The chi-square test was applied to compare the genotype frequency between patients and controls. Results A significant increase in the G/A+A/A genotype of MSH3 Pro222Pro was observed in patients compared to controls (OR, 1.87; 95% CI, 1.0–3.5). The frequency of A/G + G/G genotypes of MSH3 exon23 Thr1036Ala also tended to increase in patients (OR, 1.57; 95% CI, 0.92–2.72). Among p53 codon72 Arg/Pro + Pro/Pro carriers, the frequency of the AG + GG genotype of MSH3 exon23 was significantly increased in patients compared to controls (OR = 2.1, 95% CI; 1.05–4.34). Conclusion This is the first report on the association of MSH3 gene polymorphisms in prostate cancer. These results suggest that the MSH3 polymorphism may be a risk factor for prostate cancer. PMID:18355840

Randomly amplified polymorphic DNA linkage relationships in different Norway spruce populations

Treesearch

M. Troggio; Thomas L. Kubisiak; G. Bucci; P. Menozzi

2001-01-01

We tested the constancy of linkage relationships of randomly amplified polymorphic DNA (RAPD) marker loci used to construct a population-based consensus map in material from an Italian stand of Picea abies (L.) Karst. in 29 individuals from three Norwegian populations. Thirteen marker loci linked in the Italian stand did show a consistent locus...

Transforming growth factor-β and toll-like receptor-4 polymorphisms are not associated with fibrosis in haemochromatosis

PubMed Central

Wood, Marnie J; Powell, Lawrie W; Dixon, Jeannette L; Subramaniam, V Nathan; Ramm, Grant A

2013-01-01

AIM: To investigate the role of genetic polymorphisms in the progression of hepatic fibrosis in hereditary haemochromatosis. METHODS: A cohort of 245 well-characterised C282Y homozygous patients with haemochromatosis was studied, with all subjects having liver biopsy data and DNA available for testing. This study assessed the association of eight single nucleotide polymorphisms (SNPs) in a total of six genes including toll-like receptor 4 (TLR4), transforming growth factor-beta (TGF-β), oxoguanine DNA glycosylase, monocyte chemoattractant protein 1, chemokine C-C motif receptor 2 and interleukin-10 with liver disease severity. Genotyping was performed using high resolution melt analysis and sequencing. The results were analysed in relation to the stage of hepatic fibrosis in multivariate analysis incorporating other cofactors including alcohol consumption and hepatic iron concentration. RESULTS: There were significant associations between the cofactors of male gender (P = 0.0001), increasing age (P = 0.006), alcohol consumption (P = 0.0001), steatosis (P = 0.03), hepatic iron concentration (P < 0.0001) and the presence of hepatic fibrosis. Of the candidate gene polymorphisms studied, none showed a significant association with hepatic fibrosis in univariate or multivariate analysis incorporating cofactors. We also specifically studied patients with hepatic iron loading above threshold levels for cirrhosis and compared the genetic polymorphisms between those with no fibrosis vs cirrhosis however there was no significant effect from any of the candidate genes studied. Importantly, in this large, well characterised cohort of patients there was no association between SNPs for TGF-β or TLR4 and the presence of fibrosis, cirrhosis or increasing fibrosis stage in multivariate analysis. CONCLUSION: In our large, well characterised group of haemochromatosis subjects we did not demonstrate any relationship between candidate gene polymorphisms and hepatic fibrosis or cirrhosis. PMID:24409064

Transforming growth factor-β and toll-like receptor-4 polymorphisms are not associated with fibrosis in haemochromatosis.

PubMed

Wood, Marnie J; Powell, Lawrie W; Dixon, Jeannette L; Subramaniam, V Nathan; Ramm, Grant A

2013-12-28

To investigate the role of genetic polymorphisms in the progression of hepatic fibrosis in hereditary haemochromatosis. A cohort of 245 well-characterised C282Y homozygous patients with haemochromatosis was studied, with all subjects having liver biopsy data and DNA available for testing. This study assessed the association of eight single nucleotide polymorphisms (SNPs) in a total of six genes including toll-like receptor 4 (TLR4), transforming growth factor-beta (TGF-β), oxoguanine DNA glycosylase, monocyte chemoattractant protein 1, chemokine C-C motif receptor 2 and interleukin-10 with liver disease severity. Genotyping was performed using high resolution melt analysis and sequencing. The results were analysed in relation to the stage of hepatic fibrosis in multivariate analysis incorporating other cofactors including alcohol consumption and hepatic iron concentration. There were significant associations between the cofactors of male gender (P = 0.0001), increasing age (P = 0.006), alcohol consumption (P = 0.0001), steatosis (P = 0.03), hepatic iron concentration (P < 0.0001) and the presence of hepatic fibrosis. Of the candidate gene polymorphisms studied, none showed a significant association with hepatic fibrosis in univariate or multivariate analysis incorporating cofactors. We also specifically studied patients with hepatic iron loading above threshold levels for cirrhosis and compared the genetic polymorphisms between those with no fibrosis vs cirrhosis however there was no significant effect from any of the candidate genes studied. Importantly, in this large, well characterised cohort of patients there was no association between SNPs for TGF-β or TLR4 and the presence of fibrosis, cirrhosis or increasing fibrosis stage in multivariate analysis. In our large, well characterised group of haemochromatosis subjects we did not demonstrate any relationship between candidate gene polymorphisms and hepatic fibrosis or cirrhosis.

D1/D2 domain of large-subunit ribosomal DNA for differentiation of Orpinomyces spp.

PubMed

Dagar, Sumit S; Kumar, Sanjay; Mudgil, Priti; Singh, Rameshwar; Puniya, Anil K

2011-09-01

This study presents the suitability of D1/D2 domain of large-subunit (LSU) ribosomal DNA (rDNA) for differentiation of Orpinomyces joyonii and Orpinomyces intercalaris based on PCR-restriction fragment length polymorphism (RFLP). A variation of G/T in O. intercalaris created an additional restriction site for AluI, which was used as an RFLP marker. The results demonstrate adequate heterogeneity in the LSU rDNA for species-level differentiation.

High-throughput genotyping of hop (Humulus lupulus L.) utilising diversity arrays technology (DArT).

PubMed

Howard, E L; Whittock, S P; Jakše, J; Carling, J; Matthews, P D; Probasco, G; Henning, J A; Darby, P; Cerenak, A; Javornik, B; Kilian, A; Koutoulis, A

2011-05-01

Implementation of molecular methods in hop (Humulus lupulus L.) breeding is dependent on the availability of sizeable numbers of polymorphic markers and a comprehensive understanding of genetic variation. However, use of molecular marker technology is limited due to expense, time inefficiency, laborious methodology and dependence on DNA sequence information. Diversity arrays technology (DArT) is a high-throughput cost-effective method for the discovery of large numbers of quality polymorphic markers without reliance on DNA sequence information. This study is the first to utilise DArT for hop genotyping, identifying 730 polymorphic markers from 92 hop accessions. The marker quality was high and similar to the quality of DArT markers previously generated for other species; although percentage polymorphism and polymorphism information content (PIC) were lower than in previous studies deploying other marker systems in hop. Genetic relationships in hop illustrated by DArT in this study coincide with knowledge generated using alternate methods. Several statistical analyses separated the hop accessions into genetically differentiated North American and European groupings, with hybrids between the two groups clearly distinguishable. Levels of genetic diversity were similar in the North American and European groups, but higher in the hybrid group. The markers produced from this time and cost-efficient genotyping tool will be a valuable resource for numerous applications in hop breeding and genetics studies, such as mapping, marker-assisted selection, genetic identity testing, guidance in the maintenance of genetic diversity and the directed breeding of superior cultivars.

Substitutions of short heterologous DNA segments of intragenomic or extragenomic origins produce clustered genomic polymorphisms

PubMed Central

Harms, Klaus; Lunnan, Asbjørn; Hülter, Nils; Mourier, Tobias; Vinner, Lasse; Andam, Cheryl P.; Marttinen, Pekka; Fridholm, Helena; Hansen, Anders Johannes; Hanage, William P.; Nielsen, Kaare Magne; Willerslev, Eske; Johnsen, Pål Jarle

2016-01-01

In a screen for unexplained mutation events we identified a previously unrecognized mechanism generating clustered DNA polymorphisms such as microindels and cumulative SNPs. The mechanism, short-patch double illegitimate recombination (SPDIR), facilitates short single-stranded DNA molecules to invade and replace genomic DNA through two joint illegitimate recombination events. SPDIR is controlled by key components of the cellular genome maintenance machinery in the gram-negative bacterium Acinetobacter baylyi. The source DNA is primarily intragenomic but can also be acquired through horizontal gene transfer. The DNA replacements are nonreciprocal and locus independent. Bioinformatic approaches reveal occurrence of SPDIR events in the gram-positive human pathogen Streptococcus pneumoniae and in the human genome. PMID:27956618

Mitochondrial Haplogroup T Is Associated with Obesity in Austrian Juveniles and Adults

PubMed Central

Ebner, Sabine; Mangge, Harald; Langhof, Helmut; Halle, Martin; Siegrist, Monika; Aigner, Elmar; Paulmichl, Katharina; Paulweber, Bernhard; Datz, Christian; Sperl, Wolfgang; Kofler, Barbara; Weghuber, Daniel

2015-01-01

Background Recent publications have reported contradictory data regarding mitochondrial DNA (mtDNA) variation and its association with body mass index. The aim of the present study was to compare the frequencies of mtDNA haplogroups as well as control region (CR) polymorphisms of obese juveniles (n = 248) and obese adults (n = 1003) versus normal weight controls (njuvenile = 266, nadults = 595) in a well-defined, ethnically homogenous, age-matched comparative cohort of Austrian Caucasians. Methodology and Principal Findings Using SNP analysis and DNA sequencing, we identified the nine major European mitochondrial haplogroups and CR polymorphisms. Of these, only the T haplogroup frequency was increased in the juvenile obese cohort versus the control subjects [11.7% in obese vs. 6.4% in controls], although statistical significance was lost after adjustment for sex and age. Similar data were observed in a local adult cohort, in which haplogroup T was found at a significantly higher frequency in the overweight and obese subjects than in the normal weight group [9.7% vs. 6.2%, p = 0.012, adjusted for sex and age]. When all obese subjects were considered together, the difference in the frequency of haplogroup T was even more clearly seen [10.1% vs. 6.3%, p = 0.002, OR (95% CI) 1.71 (1.2–2.4), adjusted for sex and age]. The frequencies of the T haplogroup-linked CR polymorphisms C16294T and the C16296T were found to be elevated in both the juvenile and the adult obese cohort compared to the controls. Nevertheless, no mtDNA haplogroup or CR polymorphism was robustly associated with any of several investigated metabolic and cardiovascular parameters (e.g., blood pressure, blood glucose concentration, triglycerides, cholesterol) in all obese subjects. Conclusions and Significance By investigation of this large ethnically and geographically homogenous cohort of Middle European Caucasians, only mtDNA haplogroup T was identified as an obesity risk factor. PMID:26322975

Single nucleotide polymorphism (SNP) discovery in rainbow trout using restriction site associated DNA (RAD) sequencing of doubled haploids and assessment of polymorphism in a population survey

USDA-ARS?s Scientific Manuscript database

Background: Our goal is to produce a high-throughput SNP genotyping platform for genomic analyses in rainbow trout that will enable fine mapping of QTL, whole genome association studies, genomic selection for improved aquaculture production traits, and genetic analyses of wild populations that aid ...

Polymorphism of Paramecium pentaurelia (Ciliophora, Oligohymenophorea) strains revealed by rDNA and mtDNA sequences.

PubMed

Przyboś, Ewa; Tarcz, Sebastian; Greczek-Stachura, Magdalena; Surmacz, Marta

2011-05-01

Paramecium pentaurelia is one of 15 known sibling species of the Paramecium aurelia complex. It is recognized as a species showing no intra-specific differentiation on the basis of molecular fingerprint analyses, whereas the majority of other species are polymorphic. This study aimed at assessing genetic polymorphism within P. pentaurelia including new strains recently found in Poland (originating from two water bodies, different years, seasons, and clones of one strain) as well as strains collected from distant habitats (USA, Europe, Asia), and strains representing other species of the complex. We compared two DNA fragments: partial sequences (349 bp) of the LSU rDNA and partial sequences (618 bp) of cytochrome B gene. A correlation between the geographical origin of the strains and the genetic characteristics of their genotypes was not observed. Different genotypes were found in Kraków in two types of water bodies (Opatkowice-natural pond; Jordan's Park-artificial pond). Haplotype diversity within a single water body was not recorded. Likewise, seasonal haplotype differences between the strains within the artificial water body, as well as differences between clones originating from one strain, were not detected. The clustering of some strains belonging to different species was observed in the phylogenies. Copyright © 2010 Elsevier GmbH. All rights reserved.

Characterization of class II alpha genes and DLA-D region allelic associations in the dog.

PubMed

Sarmiento, U M; Storb, R F

1988-10-01

Human major histocompatibility complex (HLA) cDNA probes were used to analyze the restriction fragment length polymorphism (RFLP) of the alpha genes of the DLA-D region in dogs. Genomic DNA from peripheral blood leucocytes of 23 unrelated DLA-D homozygous dogs representing nine DLA-D types (defined by mixed leucocyte reaction) was digested with restriction enzymes (BamHI, EcoRI, Hind III, Pvu II, Taq I, Rsa I, Msp I, Pst I and Bgl II), separated by agarose gel electrophoresis and transferred onto Biotrace membrane. The Southern blots were successively hybridized with radiolabelled HLA cDNA probes corresponding to DQ, DP, DZ and DR alpha genes. Clear evidence was obtained for the canine homologues of DQ and DR alpha genes with simple bi- or tri-allelic polymorphism respectively. Evidence for a single, nonpolymorphic DP alpha gene was also obtained. However, the presence of a DZ alpha gene could not be clearly demonstrated in canine genomic DNA. This report extends our previous RFLP analysis documenting polymorphism of DLA class II beta genes in the same panel of homozygous typing cell dogs, and provides the basis for DLA-D genotyping at a population level. This study also characterizes the RFLP-defined preferential allelic associations across the DLA-D region in nine different homozygous typing cell specificities.

Analysis of DNA Methylation of Gracilariopsis lemaneiformis Under Temperature Stress Using the Methylation Sensitive Amplification Polymorphism (MSAP) Technique

NASA Astrophysics Data System (ADS)

Peng, Chong; Sui, Zhenghong; Zhou, Wei; Hu, Yiyi; Mi, Ping; Jiang, Minjie; Li, Xiaodong; Ruan, Xudong

2018-06-01

Gracilariopsis lemaneiformis is an economically important agarophyte, which contains high quality gel and shows a high growth rate. Wild population of G. lemaneiformis displayed resident divergence, though with a low genetic diversity as was revealed by amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) analyses. In addition, different strains of G. lemaneiformis are diverse in morphology. The highly inconsistence between genetic background and physiological characteristics recommends strongly to the regulation at epigenetic level. In this study, the DNA methylation change in G. lemaneiformis among different generation branches and under different temperature stresses was assessed using methylation sensitive amplified polymorphism (MSAP) technique. It was shown that DNA methylation level among different generation branches was diverse. The full and total methylated DNA level was the lowest in the second generation branch and the highest in the third generation. The total methylation level was 61.11%, 60.88% and 64.12% at 15°C, 22°C and 26°C, respectively. Compared with the control group (22°C), the fully methylated and totally methylated ratios were increased in both experiment groups (15°C and 26°C). All of the cytosine methylation/demethylation transform (CMDT) was further analyzed. High temperature treatment could induce more CMDT than low temperature treatment did.

DNA methylation levels analysis in four tissues of sea cucumber Apostichopus japonicus based on fluorescence-labeled methylation-sensitive amplified polymorphism (F-MSAP) during aestivation.

PubMed

Zhao, Ye; Chen, Muyan; Storey, Kenneth B; Sun, Lina; Yang, Hongsheng

2015-03-01

DNA methylation plays an important role in regulating transcriptional change in response to environmental stimuli. In the present study, DNA methylation levels of tissues of the sea cucumber Apostichopus japonicus were analyzed by the fluorescence-labeled methylation-sensitive amplified polymorphism (F-MSAP) technique over three stages of the aestivation cycle. Overall, a total of 26,963 fragments were amplified including 9112 methylated fragments among four sea cucumber tissues using 18 pairs of selective primers. Results indicated an average DNA methylation level of 33.79% for A. japonicus. The incidence of DNA methylation was different across tissue types in the non-aestivation stage: intestine (30.16%), respiratory tree (27.61%), muscle (27.94%) and body wall (56.25%). Our results show that hypermethylation accompanied deep-aestivation in A. japonicus, which suggests that DNA methylation may have an important role in regulating global transcriptional suppression during aestivation. Further analysis indicated that the main DNA modification sites were focused on intestine and respiratory tree tissues and that full-methylation but not hemi-methylation levels exhibited significant increases in the deep-aestivation stage. Copyright © 2014 Elsevier Inc. All rights reserved.

Molecular genetic studies in Saudi population; identified variants from GWAS and meta-analysis in stroke.

PubMed

Alharbi, Khalid Khalaf; Ali Khan, Imran; Alotaibi, Mohammad Abdullah; Saud Aloyaid, Abdullah; Al-Basheer, Haifa Abdulaziz; Alghamdi, Naelah Abdullah; Al-Baradie, Raid Saleem; Al-Sulaiman, A M

2018-01-01

Stroke is a multifactorial and heterogeneous disorder, correlates with heritability and considered as one of the major diseases. The prior reports performed the variable models such as genome-wide association studies (GWAS), replication, case-control, cross-sectional and meta-analysis studies and still, we lack diagnostic marker in the global world. There are limited studies were carried out in Saudi population, and we aim to investigate the molecular association of single nucleotide polymorphisms (SNPs) identified through GWAS and meta-analysis studies in stroke patients in the Saudi population. In this case-control study, we have opted gender equality of 207 cases and 207 controls from the capital city of Saudi Arabia in King Saud University Hospital. The peripheral blood (5 ml) sample will be collected in two different vacutainers, and three mL of the coagulated blood will be used for lipid analysis (biochemical tests) and two mL will be used for DNA analysis (molecular tests). Genomic DNA will be extracted with the collected blood samples, and specific primers will be designed for the opted SNPs ( SORT1 -rs646218 and OLR1 -rs11053646 polymorphisms) and PCR-RFLP will be performed and randomly DNA sequencing will be carried out to cross check the results. The rs646218 and rs11053646 polymorphisms were significantly associated with allele, genotype and dominant models with and without crude odds ratios (OR's) and Multiple logistic regression analysis (p < 0.05). Correlation between lipid profile and genotypes has confirmed the significant relation between triglycerides and rs646218 and rs1105364 6polymorphisms. However, rs11053646 polymorphism was correlated with HDLC (p = 0.04). Genotypes were examined in both males' vs. males and females' vs. females in cases and control and we concluded that in rs11053646 polymorphisms with male subjects compared between cases and controls found to be associated with dominant model heterozygote genotypes (p < 0.05). The results of the current study confirmed the SORT1 and OLR1  SNPs were associated in the Saudi population. The current results were in the association with the prior study results documented through GWAS and meta-analysis association. However, other ethnic population studies should be performed to rule out in the human hereditary diseases.

Comparative analyses of genetic/epigenetic diversities and structures in a wild barley species (Hordeum brevisubulatum) using MSAP, SSAP and AFLP.

PubMed

Shan, X H; Li, Y D; Liu, X M; Wu, Y; Zhang, M Z; Guo, W L; Liu, B; Yuan, Y P

2012-08-17

We analyzed genetic diversity and population genetic structure of four artificial populations of wild barley (Hordeum brevisubulatum); 96 plants collected from the Songnen Prairie in northeastern China were analyzed using amplified fragment length polymorphism (AFLP), specific-sequence amplified polymorphism (SSAP) and methylation-sensitive amplified polymorphism (MSAP) markers. Indices of (epi-)genetic diversity, (epi-)genetic distance, gene flow, genotype frequency, cluster analysis, PCA analysis and AMOVA analysis generated from MSAP, AFLP and SSAP markers had the same trend. We found a high level of correlation in the artificial populations between MSAP, SSAP and AFLP markers by the Mantel test (r > 0.8). This is incongruent with previous findings showing that there is virtually no correlation between DNA methylation polymorphism and classical genetic variation; the high level of genetic polymorphism could be a result of epigenetic regulation. We compared our results with data from natural populations. The population diversity of the artificial populations was lower. However, different from what was found using AFLP and SSAP, based on MSAP results the methylation polymorphism of the artificial populations was not significantly reduced. This leads us to suggest that the DNA methylation pattern change in H. brevisubulatum populations is not only related to DNA sequence variation, but is also regulated by other controlling systems.

Genetic discovery in Xylella fastidiosa through sequence analysis of selected randomly amplified polymorphic DNAs.

PubMed

Chen, Jianchi; Civerolo, Edwin L; Jarret, Robert L; Van Sluys, Marie-Anne; de Oliveira, Mariana C

2005-02-01

Xylella fastidiosa causes many important plant diseases including Pierce's disease (PD) in grape and almond leaf scorch disease (ALSD). DNA-based methodologies, such as randomly amplified polymorphic DNA (RAPD) analysis, have been playing key roles in genetic information collection of the bacterium. This study further analyzed the nucleotide sequences of selected RAPDs from X. fastidiosa strains in conjunction with the available genome sequence databases and unveiled several previously unknown novel genetic traits. These include a sequence highly similar to those in the phage family of Podoviridae. Genome comparisons among X. fastidiosa strains suggested that the "phage" is currently active. Two other RAPDs were also related to horizontal gene transfer: one was part of a broadly distributed cryptic plasmid and the other was associated with conjugal transfer. One RAPD inferred a genomic rearrangement event among X. fastidiosa PD strains and another identified a single nucleotide polymorphism of evolutionary value.

Genetic polymorphisms in 19q13.3 genes associated with alteration of repair capacity to BPDE-DNA adducts in primary cultured lymphocytes.

PubMed

Xiao, Mingyang; Xiao, Sha; Straaten, Tahar van der; Xue, Ping; Zhang, Guopei; Zheng, Xiao; Zhang, Qianye; Cai, Yuan; Jin, Cuihong; Yang, Jinghua; Wu, Shengwen; Zhu, Guolian; Lu, Xiaobo

2016-12-01

Benzo[a]pyrene(B[a]P), and its ultimate metabolite Benzo[a]pyrene 7,8-diol 9,10-epoxide (BPDE), are classic DNA damaging carcinogens. DNA damage in cells caused by BPDE is normally repaired by Nucleotide Excision Repair (NER) and Base Excision Repair (BER). Genetic variations in NER and BER can change individual DNA repair capacity to DNA damage induced by BPDE. In the present study we determined the number of in vitro induced BPDE-DNA adducts in lymphocytes, to reflect individual susceptibility to Polycyclic aromatic hydrocarbons (PAHs)-induced carcinogenesis. The BPDE-DNA adduct level in lymphocytes were assessed by high performance liquid chromatography (HPLC) in 281 randomly selected participants. We genotyped for 9 single nucleotide polymorphisms (SNPs) in genes involved in NER (XPB rs4150441, XPC rs2228001, rs2279017 and XPF rs4781560), BER (XRCC1 rs25487, rs25489 and rs1799782) and genes located on chromosome 19q13.2-3 (PPP1R13L rs1005165 and CAST rs967591). We found that 3 polymorphisms in chromosome 19q13.2-3 were associated with lower levels of BPDE-DNA adducts (MinorT allele in XRCC1 rs1799782, minor T allele in PPP1R13L rs1005165 and minor A allele in CAST rs967571). In addition, a modified comet assay was performed to further confirm the above conclusions. We found both minor T allele in PPP1R13L rs1005165 and minor A allele in CAST rs967571 were associated with the lower levels of BPDE-adducts. Our data suggested that the variant genotypes of genes in chromosome 19q13.2-3 are associated with the alteration of repair efficiency to DNA damage caused by Benzo[a]pyrene, and may contribute to enhance predictive value for individual's DNA repair capacity in response to environmental carcinogens. Copyright © 2016 Elsevier B.V. All rights reserved.

Assessment of genetic diversity among Indian potato (Solanum tuberosum L.) collection using microsatellite and retrotransposon based marker systems.

PubMed

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.

The Dual Challenges of Generality and Specificity When Developing Environmental DNA Markers for Species and Subspecies of Oncorhynchus.

PubMed

Wilcox, Taylor M; Carim, Kellie J; McKelvey, Kevin S; Young, Michael K; Schwartz, Michael K

2015-01-01

Environmental DNA (eDNA) sampling is a powerful tool for detecting invasive and native aquatic species. Often, species of conservation interest co-occur with other, closely related taxa. Here, we developed qPCR (quantitative PCR) markers which distinguish westslope cutthroat trout (Oncorhynchus clarkii lewsi), Yellowstone cutthroat trout (O. clarkii bouvieri), and rainbow trout (O. mykiss), which are of conservation interest both as native species and as invasive species across each other's native ranges. We found that local polymorphisms within westslope cutthroat trout and rainbow trout posed a challenge to designing assays that are generally applicable across the range of these widely-distributed species. Further, poorly-resolved taxonomies of Yellowstone cutthroat trout and Bonneville cutthroat trout (O. c. utah) prevented design of an assay that distinguishes these recognized taxa. The issues of intraspecific polymorphism and unresolved taxonomy for eDNA assay design addressed in this study are likely to be general problems for closely-related taxa. Prior to field application, we recommend that future studies sample populations and test assays more broadly than has been typical of published eDNA assays to date.

Chloroplast DNA polymorphism and evolutional relationships between Asian cultivated rice (Oryza sativa) and its wild relatives (O. rufipogon).

PubMed

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.

Evaluation of Human FcγRIIA (CD32) and FcγRIIIB (CD16) Polymorphisms in Caucasians and African-Americans Using Salivary DNA

PubMed Central

van Schie, Rob C. A. A.; Wilson, Mark E.

2000-01-01

Two classes of low-affinity receptors for the Fc region of immunoglobulin G (IgG) (FcγR) are constitutively expressed on resting human neutrophils. These receptors, termed FcγRIIa (CD32) and FcγRIIIb (CD16), display biallelic polymorphisms which have functional consequences with respect to binding and/or ingestion of targets opsonized by human IgG subclass antibodies. The H131-R131 polymorphism of CD32 influences binding of human IgG2 and, to a lesser extent, human IgG3 to neutrophils. The neutrophil antigen (NA1-NA2) polymorphism of CD16 influences the efficiency of phagocytosis of bacteria opsonized by human IgG1 and IgG3. These polymorphisms may influence host susceptibility to certain infectious and/or autoimmune diseases, prompting interest in the development of facile methods for determination of CD32 and CD16 genotype in various clinical settings. We previously reported that genomic DNA from saliva is a suitable alternative to DNA from blood in PCR-based analyses of CD32 and CD16 polymorphisms. In the present study, we utilized for the first time this salivary DNA-based methodology to define CD32 and CD16 genotypes in 271 Caucasian and 118 African-American subjects and to investigate possible linkage disequilibrium between certain CD32 and CD16 genotypes in these two ethnic groups. H131 and R131 gene frequencies were 0.45 and 0.55, respectively, among Caucasians and 0.59 among African-Americans. NA1 and NA2 gene frequencies were 0.38 and 0.62 among Caucasians and 0.39 and 0.61 among African-Americans. Since FcγRIIa and FcγRIIIb synergize in triggering neutrophils, we also assessed the frequency of different CD32 and CD16 genotype combinations in these two groups. In both groups, the R/R131-NA2/NA2 genotype combination was more common than the H/H131-NA1/NA1 combination (threefold for Caucasians versus sevenfold for African-Americans). Whether individuals with the combined R/R131-NA2/NA2 genotype are at greater risk for development of infectious and/or autoimmune diseases requires further investigation, which can be conveniently performed using DNA from saliva rather than blood. PMID:10882671

Database on natural polymorphisms and resistance-related non-synonymous mutations in thymidine kinase and DNA polymerase genes of herpes simplex virus types 1 and 2.

PubMed

Sauerbrei, Andreas; Bohn-Wippert, Kathrin; Kaspar, Marisa; Krumbholz, Andi; Karrasch, Matthias; Zell, Roland

2016-01-01

The use of genotypic resistance testing of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) is increasing because the rapid availability of results significantly improves the treatment of severe infections, especially in immunocompromised patients. However, an essential precondition is a broad knowledge of natural polymorphisms and resistance-associated mutations in the thymidine kinase (TK) and DNA polymerase (pol) genes, of which the DNA polymerase (Pol) enzyme is targeted by the highly effective antiviral drugs in clinical use. Thus, this review presents a database of all non-synonymous mutations of TK and DNA pol genes of HSV-1 and HSV-2 whose association with resistance or natural gene polymorphism has been clarified by phenotypic and/or functional assays. In addition, the laboratory methods for verifying natural polymorphisms or resistance mutations are summarized. This database can help considerably to facilitate the interpretation of genotypic resistance findings in clinical HSV-1 and HSV-2 strains. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

DNA barcoding of western North American taxa: Leymus (Poaceae) and Lepidium (Brassicaceae)

Treesearch

Catherine Mae Culumber

2007-01-01

My objective was to determine if polymorphic information from the 18S-5.8S-26S nuclear ribosomal DNA internal transcribed spacer regions and the trnK-psbA, trnK-rps16 chloroplast DNA spacer regions is sufficient 1) to identify a plant specimen to the species level, and 2) to establish the phylogenetic relationship between species. The first study examined the...

SstI Polymorphism of the Apolipoprotein CIII Gene in Iranian Hyperlipidemic Patients: A Study in Semnan Province

PubMed Central

Bandegi, Ahmad Reza; Firoozrai, Mohsen; Akbari Eidgahi, Mohammad Reza; Kokhaei, Parviz

2011-01-01

Objective(s) The Sst-I polymorphic site on the 3' untranslated region of the apo CIII gene, has been previously reported to be associated with hypertriglyceridemia. The aim of the present study was to explore the association between Sst-I polymorphism with plasma lipid and lipoprotein levels in hyperlipidemic (HLP) patients from Semnan province, Iran. Materials and Methods Genomic DNA was prepared from 76 patients with HLP and 75 matched healthy subjects. DNA samples were amplified by polymerase chain reaction. The samples were analyzed by restriction fragment length polymorphism (RFLP) method using SstI enzyme. Results The genotype and allelic frequencies for this polymorphism were significantly different between HLP and normolipidemic groups (P< 0.002). Plasma triglyceride (TG) level was higher in both groups, in S2S2 genotype was more than in the S1S1and S1S2 genotypes, however, there was no significant difference in comparison with the control group. Subjects with S1S2 + S2S2 genotypes in compare to S1S1 genotype had odd ratio of 2.8 (95% CI: 1.41-5.56, P< 0.003) for developing hypertriglyceridemia. Conclusion The results showed that the presence of rare S2 allele was associated with change in TG level in the selected population. PMID:23493241

Association of the Risk of Dental Caries and Polymorphism of MBL2 rs11003125 Gene in Iranian Adults.

PubMed

Mokhtari, Mohammad Javad; Koohpeima, Fatemeh; Hashemi-Gorji, Feyzollah

2018-06-14

This case-control study aimed to investigate the effect of rs11003125 in dental caries. For this purpose, a total number of 404 individuals - from Fars Province in Iran - were studied. The technique of this research was the tetra-primer amplification-refractory mutation system (ARMS)-PCR. Dental caries prevalence among the 404 individuals was assessed by counting the number of decayed, missing, and filled teeth. In this research, individuals were divided into two groups: cases (n = 238) and controls (n = 166), and the peripheral blood samples were used to extract the genomic DNA. For genotyping of DNA, the tetra-primer ARMS-PCR method was conducted using specific primer pairs. While examining MBL2 rs11003125 polymorphism, we found significant differences in the genotype frequencies between the case and the control group. The pooled estimates indicated that the GG and GC genotypes of MBL2 rs11003125 polymorphism significantly increased, and therefore caries risk (OR = 2.40, 95% CI = 1.31-4.40, p = 0.004) under the dominant model. These findings suggested that polymorphism in MBL2 gene was associated with dental caries in Iranian adults. Further verification is needed with more ethnic groups and larger sample sizes to determine whether rs11003125 polymorphism is related to dental caries in other regions or not. © 2018 S. Karger AG, Basel.

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

Gilchrist, Michael J.; Sobral, Daniel; Khoueiry, Pierre

Genome-wide resources, such as collections of cDNA clones encoding for complete proteins (full-ORF clones), are crucial tools for studying the evolution of gene function and genetic interactions. Non-model organisms, in particular marine organisms, provide a rich source of functional diversity. Marine organism genomes are, however, frequently highly polymorphic and encode proteins that diverge significantly from those of well-annotated model genomes. The construction of full-ORF clone collections from non-model organisms is hindered by the difficulty of predicting accurately the N-terminal ends of proteins, and distinguishing recent paralogs from highly polymorphic alleles. We also report a computational strategy that overcomes these difficulties,more » and allows for accurate gene level clustering of transcript data followed by the automated identification of full-ORFs with correct 5'- and 3'-ends. It is robust to polymorphism, includes paralog calling and does not require evolutionary proximity to well annotated model organisms. Here, we developed this pipeline for the ascidian Ciona intestinalis, a highly polymorphic member of the divergent sister group of the vertebrates, emerging as a powerful model organism to study chordate gene function, Gene Regulatory Networks and molecular mechanisms underlying human pathologies. Furthermore, using this pipeline we have generated the first full-ORF collection for a highly polymorphic marine invertebrate. It contains 19,163 full-ORF cDNA clones covering 60% of Ciona coding genes, and full-ORF orthologs for approximately half of curated human disease-associated genes.« less

The role of xenobotic metabolism MGST1 gene polymorphism in colorectal cancer patients.

PubMed

Akil, Fardah; Akil, H A M; Lutfie, A M; Wibowo, Wahyu S; Miskad, Upik; Yusuf, Irawan

2012-10-01

to asses the role of Microsomal Glutathione S-Transferase1 (MGST1) gene as one of enzym metabolism that plays in enviromental factor. using case-control study, subjects with age less than 50 years were collected from teaching hospital Makassar between 2008-2010. Frozen or routinely processed tumour samples biopsy and peripheral blood were obtained from 35 CRC patients undergoing surgery and endoscopic examination with 61 subject as control. CRC cases were diagnosis by clinical examination and confirm by histopathology without familial aggregation of CRC. DNA resequencing was conducted for the 3 kb genomic DNA region MGST1 using PCR-restriction fragment length polymorphism (PCR-RFLP). from 96 subject, two varian single nucleotide polymorphisms (SNPs) 16454T>G and 16416G>A MGST1 were identified. Significant CRC association (p= 0.047) was detected in GG genotipe SNP 16454T>G MGST1 with 3.5 fold risk (95% confidence interval (CI) 0.962-13.191). the results suggest that MGST1 gene polymorphisms as one of environment gene may contribute to CRC risk in younger age (<50 years old).

Genotyping and Bioforensics of Ricinus communis

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

Hinckley, Aubree Christine

The castor bean plant (Ricinus communis) is a member of the family Euphorbiaceae. In spite of its common name, the castor plant is not a true bean (i.e., leguminous plants belonging to the family, Fabaceae). Ricinus communis is native to tropical Africa, but because the plant was recognized for its production of oil with many desirable properties, it has been introduced and cultivated in warm temperate regions throughout the world (Armstrong 1999 and Brown 2005). Castor bean plants have also been valued by gardeners as an ornamental plant and, historically, as a natural rodenticide. Today, escaped plants grow like weedsmore » throughout much of the southwestern United States, and castor seeds are even widely available to the public for order through the Internet. In this study, multiple loci of chloroplast noncoding sequence data and a few nuclear noncoding regions were examined to identify DNA polymorphisms present among representatives from a geographically diverse panel of Ricinus communis cultivated varieties. The primary objectives for this research were (1) to successfully cultivate castor plants and extract sufficient yields of high quality DNA from an assortment of castor cultivated varieties, (2) to use PCR and sequencing to screen available universal oligos against a small panel of castor cultivars, (3) to identify DNA polymorphisms within the amplified regions, and (4) to evaluate these DNA polymorphisms as appropriate candidates for assay development (see Figure 1). Additional goals were to design, test and optimize assays targeting any DNA polymorphisms that were discovered and to rapidly screen many castor cultivars to determine the amount of diversity present at that particular locus. Ultimately, the goal of this study was to construct a phylogeographic tree representing the genetic relationships present among Ricinus communis cultivars from diverse geographic regions. These research objectives were designed to test the hypothesis that cultivated varieties of Ricinus communis from various geographic regions can be distinguished from one another based on differences present at the genetic level. In addition, the present study sought to determine the amount of diversity present among Ricinus communis cultivars.« less

XPD polymorphisms: effects on DNA repair proficiency.

PubMed

Lunn, R M; Helzlsouer, K J; Parshad, R; Umbach, D M; Harris, E L; Sanford, K K; Bell, D A

2000-04-01

XPD codes for a DNA helicase involved in transcription and nucleotide excision repair. Rare XPD mutations diminish nucleotide excision repair resulting in hypersensitivity to UV light and increased risk of skin cancer. Several polymorphisms in this gene have been identified but their impact on DNA repair is not known. We compared XPD genotypes at codons 312 and 751 with DNA repair proficiency in 31 women. XPD genotypes were measured by PCR-RFLP. DNA repair proficiency was assessed using a cytogenetic assay that detects X-ray induced chromatid aberrations (breaks and gaps). Chromatid aberrations were scored per 100 metaphase cells following incubation at 37 degrees C (1.5 h after irradiation) to allow for repair of DNA damage. Individuals with the Lys/Lys codon 751 XPD genotype had a higher number of chromatid aberrations (132/100 metaphase cells) than those having a 751Gln allele (34/100 metaphase cells). Individuals having greater than 60 chromatid breaks plus gaps were categorized as having sub-optimal repair. Possessing a Lys/Lys751 genotype increased the risk of sub-optimal DNA repair (odds ratio = 7.2, 95% confidence interval = 1.01-87.7). The Asp312Asn XPD polymorphism did not appear to affect DNA repair proficiency. These results suggest that the Lys751 (common) allele may alter the XPD protein product resulting in sub-optimal repair of X-ray-induced DNA damage.

A standard photomap of ovarian nurse cell chromosomes and inversion polymorphism in Anopheles beklemishevi.

PubMed

Artemov, Gleb N; Gordeev, Mikhail I; Kokhanenko, Alina A; Moskaev, Anton V; Velichevskaya, Alena I; Stegniy, Vladimir N; Sharakhov, Igor V; Sharakhova, Maria V

2018-03-27

Anopheles beklemishevi is a member of the Maculipennis group of malaria mosquitoes that has the most northern distribution among other members of the group. Although a cytogenetic map for the larval salivary gland chromosomes of this species has been developed, a high-quality standard cytogenetic photomap that enables genomics and population genetics studies of this mosquito at the adult stage is still lacking. In this study, a cytogenetic map for the polytene chromosomes of An. beklemishevi from ovarian nurse cells was developed using high-resolution digital imaging from field collected mosquitoes. PCR-amplified DNA probes for fluorescence in situ hybridization (FISH) were designed based on the genome of An. atroparvus. The DNA probe obtained by microdissection procedures from the breakpoint region was labelled in a DOP-PCR reaction. Population analysis was performed on 371 specimens collected in 18 locations. We report the development of a high-quality standard photomap for the polytene chromosomes from ovarian nurse cells of An. beklemishevi. To confirm the suitability of the map for physical mapping, several PCR-amplified probes were mapped to the chromosomes of An. beklemishevi using FISH. In addition, we identified and mapped DNA probes to flanking regions of the breakpoints of two inversions on chromosome X of this species. Inversion polymorphism was determined in 13 geographically distant populations of An. beklemishevi. Four polymorphic inversions were detected. The positions of common chromosomal inversions were indicated on the map. The study constructed a standard photomap for ovarian nurse cell chromosomes of An. beklemishevi and tested its suitability for physical genome mapping and population studies. Cytogenetic analysis determined inversion polymorphism in natural populations of An. beklemishevi related to this species' adaptation.

Genetic Diversity of Pinus Roxburghii Sarg. Collected from Different Himalayan Regions of India Assessed by Random Amplified Polymorphic DNA Analysis

PubMed Central

Sinha, Dwaipayan; Singh, Jyotsna; Tandon, P. K.; Kakkar, Poonam

2013-01-01

Present study was aimed at molecular genetic fingerprint profile of 15 genotypes of three populations of Pinus roxburghii Sarg. from Himalayan regions of India using random amplified polymorphic DNA (RAPD) based markers. Needles of Pinus roxburghii Sarg. were collected from Dharamshala, Himachal Pradesh (HP), Nainital, Uttarakhand (UK) and Darjeeling, West Bengal (WB) regions of India. The samples were subjected to DNA extraction and RAPD analysis using oligonucleotide purification cartridge (OPC) primers. Out of 15 primers tested, nine primers gave scorable bands. Altogether 48 bands were obtained, out of which 43 were found to be polymorphic. Number of amplified fragments with RAPD primers ranged from four to eight with the size of amplicon ranging from 500 to 7,000bp. Investigation of natural diversity at intraspecies level was performed with 15 genotypes. Forty-eight amplification products were scored by RAPD and showed 89.58% polymorphism with a mean intrapopulation genetic diversity (Hpop) of 0.2754. A significant inter- and intrapopulation diversity was observed, with the percentage of polymorphic loci (Pp) ranging from 50.09 to 70.83%, Shannon's information index (I) from 0.3262 to 0.4689 and Nei's gene diversity (h) from 0.2032 to 0.3335 with mean Nei's gene diversity 0.377 and the overall estimate of gene flow being (Nm) 1.3555. Unweighted pair-group method with arithmetic average (UPGMA) analysis based Dendrogram showed single cluster. The variation amongst the samples of the three ecological regions can be attributed to varied climatic conditions and may help in conservation/future cultivation of these species. PMID:24403729

[Genetic polymorphism of flax Linum usitatissimum based on use of molecular cytogenetic markers].

PubMed

Rachinskaia, O A; Lemesh, V A; Muravenko, O V; Iurkevich, O Iu; Guzenko, E V; Bol'sheva, N L; Bogdanova, M V; Samatadze, T E; Popov, K V; Malyshev, S V; Shostak, N G; Heller, K; Khotyleva, L V; Zelenin, A V

2011-01-01

Using a set of approaches based on the use of molecular cytogenetic markers (DAPI/C-banding, estimation of the total area of DAPI-positive regions in prophase nuclei, FISH with 26S and 5S rDNA probes) and the microsatellite (SSR-PCR) assay, we studied genomic polymorphism in 15 flax (Linum usitatissimum L.) varieties from different geographic regions belonging to three directions of selection (oil, fiber, and intermediate flaxes) and in the k-37 x Viking hybrid. All individual chromosomes have been identified in the karyotypes of these varieties on the basis of the patterns of differential DAPI/C-banding and the distribution of 26S and 5S rDNA, and idiograms of the chromosomes have been generated. Unlike the oil flax varieties, the chromosomes in the karyotypes of the fiber flax varieties have, as a rule, pericentromeric and telomeric DAPI-positive bands of smaller size, but contain larger intercalary regions. Two chromosomal rearrangements (chromosome 3 inversions) were discovered in the variety Luna and in the k-37 x Viking hybrid. In both these forms, no colocalization of 26S rDNA and 5S rDNA on the satellite chromosome was detected. The SSR assay with the use of 20 polymorphic pairs of primers revealed 22 polymorphic loci. Based on the SSR data, we analyzed genetic similarity of the flax forms studied and constructed a genetic similarity dendrogram. The genotypes studied here form three clusters. The oil varieties comprise an independent cluster. The genetically related fiber flax varieties Vita and Luna, as well as the landrace Lipinska XIII belonging to the intermediate type, proved to be closer to the oil varieties than the remaining fiber flax varieties. The results of the molecular chromosomal analysis in the fiber and oil flaxes confirm their very close genetic similarity. In spite of this, the combined use of the chromosomal and molecular markers has opened up unique possibilities for describing the genotypes of flax varieties and creating their genetic passports.

Genotoxic effects of heavy metal cadmium on growth, biochemical, cyto-physiological parameters and detection of DNA polymorphism by RAPD in Capsicum annuum L. – An important spice crop of India

PubMed Central

Aslam, Rumana; Ansari, M.Y.K.; Choudhary, Sana; Bhat, Towseef Mohsin; Jahan, Nusrat

2014-01-01

The present study was designed to investigate the effects of cadmium (Cd) on biochemical, physiological and cytological parameters of Capsicum annuum L. treated with five different concentrations (20, 40, 60, 80 and 100 ppm) of the metal. Shoot–root length, pigment and protein content showed a continuous decrease with increasing Cd concentrations and the maximal decline was observed at the higher concentration. Proline content was found to be increased upto 60 ppm while at higher concentrations it gradually decreased. MDA content and chromosomal aberrations increased as the concentration increased. Additionally Random amplified polymorphic DNA (RAPD) technique was used for the detection of genotoxicity induced by Cd. A total of 184 bands (62 polymorphic and 122 monomorphic) were generated in 5 different concentrations with 10 primers where primer OPA-02 generated the highest percentage of polymorphism (52.63%). Dendrogram showed that control, R1 and R2 showed similar cluster and R4 and R5 grouped with R3 into one cluster, which showed that plants from higher doses showed much difference than the plants selected at mild doses which resemble control at the DNA level. This investigation showed that RAPD marker is a useful tool for evaluation of genetic diversity and relationship among different metal concentrations. PMID:25313282

Haplotype data for 23 Y-chromosome markers in a reference sample from Bosnia and Herzegovina

PubMed Central

Kovačević, Lejla; Fatur-Cerić, Vera; Hadžić, Negra; Čakar, Jasmina; Primorac, Dragan; Marjanović, Damir

2013-01-01

Aim To detect polymorphisms of 23 Y-chromosomal short tandem repeat (STR) loci, including 6 new loci, in a reference database of male population of Bosnia and Herzegovina, as well as to assess the importance of increasing the number of Y-STR loci utilized in forensic DNA analysis. Methods The reference sample consisted of 100 healthy, unrelated men originating from Bosnia and Herzegovina. Sample collection using buccal swabs was performed in all geographical regions of Bosnia and Herzegovina in the period from 2010 to 2011. DNA samples were typed for 23 Y STR loci, including 6 new loci: DYS576, DYS481, DYS549, DYS533, DYS570, and DYS643, which are included in the new PowerPlex® Y 23 amplification kit. Results The absolute frequency of generated haplotypes was calculated and results showed that 98 samples had unique Y 23 haplotypes, and that only two samples shared the same haplotype. The most polymorphic locus was DYS418, with 14 detected alleles and the least polymorphic loci were DYS389I, DYS391, DYS437, and DYS393. Conclusion This study showed that by increasing the number of highly polymorphic Y STR markers, to include those tested in our analysis, leads to a reduction of repeating haplotypes, which is very important in the application of forensic DNA analysis. PMID:23771760

Methylation Sensitive Amplification Polymorphism Sequencing (MSAP-Seq)-A Method for High-Throughput Analysis of Differentially Methylated CCGG Sites in Plants with Large Genomes.

PubMed

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.

Methylation Sensitive Amplification Polymorphism Sequencing (MSAP-Seq)—A Method for High-Throughput Analysis of Differentially Methylated CCGG Sites in Plants with Large Genomes

PubMed Central

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

D1/D2 Domain of Large-Subunit Ribosomal DNA for Differentiation of Orpinomyces spp.▿

PubMed Central

Dagar, Sumit S.; Kumar, Sanjay; Mudgil, Priti; Singh, Rameshwar; Puniya, Anil K.

2011-01-01

This study presents the suitability of D1/D2 domain of large-subunit (LSU) ribosomal DNA (rDNA) for differentiation of Orpinomyces joyonii and Orpinomyces intercalaris based on PCR-restriction fragment length polymorphism (RFLP). A variation of G/T in O. intercalaris created an additional restriction site for AluI, which was used as an RFLP marker. The results demonstrate adequate heterogeneity in the LSU rDNA for species-level differentiation. PMID:21784906

Microsatellite DNA library for Caiman latirostris.

PubMed

Zucoloto, Rodrigo Barban; Verdade, Luciano Martins; Coutinho, Luiz Lehmann

2002-12-15

New genetic markers were characterized for the broad-snouted caiman (Caiman latirostris) by constructing libraries enriched for microsatellite DNA. Construction and characterization of these libraries are described in the present study. One microsatellite marker was developed from a (ACC-TGG)(n)enriched microsatellite DNA library, and 12 microsatellite markers were developed from a (AC-TG)(n)enriched microsatellite DNA library. These markers were tested in wild-caught animals, and these tests resulted in ten new polymorphic microsatellites for C. latirostris. Copyright 2002 Wiley-Liss, Inc.

The Ins and Outs of DNA Fingerprinting the Infectious Fungi

PubMed Central

Soll, David R.

2000-01-01

DNA fingerprinting methods have evolved as major tools in fungal epidemiology. However, no single method has emerged as the method of choice, and some methods perform better than others at different levels of resolution. In this review, requirements for an effective DNA fingerprinting method are proposed and procedures are described for testing the efficacy of a method. In light of the proposed requirements, the most common methods now being used to DNA fingerprint the infectious fungi are described and assessed. These methods include restriction fragment length polymorphisms (RFLP), RFLP with hybridization probes, randomly amplified polymorphic DNA and other PCR-based methods, electrophoretic karyotyping, and sequencing-based methods. Procedures for computing similarity coefficients, generating phylogenetic trees, and testing the stability of clusters are then described. To facilitate the analysis of DNA fingerprinting data, computer-assisted methods are described. Finally, the problems inherent in the collection of test and control isolates are considered, and DNA fingerprinting studies of strain maintenance during persistent or recurrent infections, microevolution in infecting strains, and the origin of nosocomial infections are assessed in light of the preceding discussion of the ins and outs of DNA fingerprinting. The intent of this review is to generate an awareness of the need to verify the efficacy of each DNA fingerprinting method for the level of genetic relatedness necessary to answer the epidemiological question posed, to use quantitative methods to analyze DNA fingerprint data, to use computer-assisted DNA fingerprint analysis systems to analyze data, and to file data in a form that can be used in the future for retrospective and comparative studies. PMID:10756003

DD genotype of ACE gene I/D polymorphism is associated with Behcet disease in a Turkish population.

PubMed

Yigit, Serbülent; Tural, Sengül; Rüstemoglu, Aydin; Inanir, Ahmet; Gul, Ulker; Kalkan, Goknur; Akkanet, Songul; Karakuş, Nevin; Ateş, Omer

2013-01-01

Behcet's disease (BD) is a chronic, multi-systemic and inflammatory disorder. The local renin-angiotensin system (RAS) in the vessel wall plays a role in the endothelial control and contributes to inflammatory processes. Angiotensin-converting enzyme (ACE) is the regulatory component of the RAS. This study was conducted in Turkish patients with BD to determine the frequency of I/D polymorphism genotypes of ACE gene. Genomic DNA obtained from 566 persons (266 patients with BD and 300 healthy controls). ACE gene I/D polymorphism genotypes were determined using polymerase chain reaction using I and D allele-specific primers. There was statistically significant difference between the groups with respect to genotype distribution (p < 0.001). This study is the largest study in Turkish population that ACE gene I/D polymorphism investigated in BD. As a result of this study, ACE gene I/D polymorphism DD genotype could be a genetic marker in BD in Turkish study population.

Structural polymorphism of a cytosine-rich DNA sequence forming i-motif structure: Exploring pH based biosensors.

PubMed

Ahmed, Saami; Kaushik, Mahima; Chaudhary, Swati; Kukreti, Shrikant

2018-05-01

Sequence recognition and conformational polymorphism enable DNA to emerge out as a substantial tool in fabricating the devices within nano-dimensions. These DNA associated nano devices work on the principle of conformational switches, which can be facilitated by many factors like sequence of DNA/RNA strand, change in pH or temperature, enzyme or ligand interactions etc. Thus, controlling these DNA conformational changes to acquire the desired function is significant for evolving DNA hybridization biosensor, used in genetic screening and molecular diagnosis. For exploring this conformational switching ability of cytosine-rich DNA oligonucleotides as a function of pH for their potential usage as biosensors, this study has been designed. A C-rich stretch of DNA sequence (5'-TCCCCCAATTAATTCCCCCA-3'; SG20c) has been investigated using UV-Thermal denaturation, poly-acrylamide gel electrophoresis and CD spectroscopy. The SG20c sequence is shown to adopt various topologies of i-motif structure at low pH. This pH dependent transition of SG20c from unstructured single strand to unimolecular and bimolecular i-motif structures can further be exploited for its utilization as switching on/off pH-based biosensors. Copyright © 2018. Published by Elsevier B.V.

Essentials of Conservation Biotechnology: A mini review

NASA Astrophysics Data System (ADS)

Merlyn Keziah, S.; Subathra Devi, C.

2017-11-01

Equilibrium of biodiversity is essential for the maintenance of the ecosystem as they are interdependent on each other. The decline in biodiversity is a global problem and an inevitable threat to the mankind. Major threats include unsustainable exploitation, habitat destruction, fragmentation, transformation, genetic pollution, invasive exotic species and degradation. This review covers the management strategies of biotechnology which include sin situ, ex situ conservation, computerized taxonomic analysis through construction of phylogenetic trees, calculating genetic distance, prioritizing the group for conservation, digital preservation of biodiversities within the coding and decoding keys, molecular approaches to asses biodiversity like polymerase chain reaction, real time, randomly amplified polymorphic DNA, restriction fragment length polymorphism, amplified fragment length polymorphism, single sequence repeats, DNA finger printing, single nucleotide polymorphism, cryopreservation and vitrification.

Evaluation of a reverse-hybridization StripAssay for the detection of genetic polymorphisms leading to acenocoumarol sensitivity.

PubMed

Gialeraki, Argyri; Markatos, Christos; Grouzi, Elisabeth; Merkouri, Efrosyni; Travlou, Anthi; Politou, Marianna

2010-04-01

Acenocoumarol is mainly catabolized by CYP2C9 isoform of cytochrome P450 (CYP) liver complex and exerts its anticoagulant effect through the inhibition of Vitamin K Epoxide Reductase (VKOR). The most important genetic polymorphisms which lead to an impaired enzymatic activity and therefore predispose to acenocoumarol sensitivity, are considered to be CYP2C9*2 (Arg144Cys), CYP2C9*3 (Ile359Leu) and VKORC1-1639G>A, respectively. In this study we compared the results of the PGXThrombo StripAssay kit (ViennaLab Diagnostics,Vienna, Austria) with direct DNA sequencing and in house Restriction Fragment Length Polymorphisms (RFLP) for the detection of the aforementioned Single Nucleotide Polymorphisms (SNPs). The reverse hybridization StripAssay was found to be equally effective with RFLP and direct DNA sequencing for the detection of CYP2C9*2 and CYP2C9*3 polymorphisms, respectively. The comparison of the RFLP reference method with the reverse hybridization StripAssay for the detection of VKORC1-1639 G>A polymorphism showed that the reverse hybridization StripAsssay might misclassify some A/A homozygotes as heterozygotes. Optimization of the hybridization procedures may eliminate the extra low signal band observed in some samples at the reverse hybridization StripAssay and improve its diagnostic value.

Association of the 5,10-methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) polymorphisms in Korean patients with adult acute lymphoblastic leukemia.

PubMed

Oh, Doyeun; Kim, Nam Keun; Jang, Moon Ju; Kim, Hugh Chul; Lee, Jae Hoon; Lee, Jung Ae; Ahn, Myung Ju; Kim, Chul Soo; Kim, Heung Sik; Park, Seonyang; Chio, Hyun Sook; Min, Yoo Hong

2007-01-01

Methylenetetrahydrofolate reductase (MTHFR) plays a central role in converting folate to methyl donor for DNA methylation. Because MTHFR is a key enzyme in folate metabolism, changes in its activity resulting from polymorphisms in the MTHFR gene could modify the susceptibility to cancer. Recently, the C677T and A1298C mutations of MTHFR were discovered to be associated with susceptibility in acute lymphoblastic leukemia (ALL). The association between MTHFR polymorphisms and susceptibility and clinical outcome in ALL was studied in 118 adult ALL patients and matched healthy controls (n =427). DNA samples taken from patients with ALL and controls were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays to detect the MTHFR C677T and A1298C mutations. No significant difference was found in the development of adult ALL among those with different MTHFR genotypes of the C677T or A1298C polymorphisms. However, the MTHFR 677CT+TT genotype showed a tendency to be associated with adult ALL [crude odds ratio (OR), 0.67; 95% confidence interval (CI), 0.44-1.02; adjusted OR, 0.74 95% CI, 0.47-1.14]. The MTHFR C677T and A1298C polymorphisms are not significant risk factors in adult acute leukemia in the Korean population.

Acute oral mucositis in nasopharyngeal carcinoma patients treated with radiotherapy: association with genetic polymorphism in DNA DSB repair genes.

PubMed

Ren, Jing-Hua; Dai, Xiao-Fang; Yan, Guo-Li; Jin, Min; Liu, Cui-Wei; Yang, Kun-Yu; Wu, Gang; Ma, C-M Charlie

2014-03-01

The aim of this study was to investigate the association between polymorphic variants of DNA repair genes with the susceptibility of acute oral mucositis (OM) in nasopharyngeal carcinoma (NPC) patients treated with radiotherapy. The study population consisted of 120 NPC patients treated with intensity-modulated radiation therapy (IMRT). Among them 70 patients also received concurrent chemotherapy. Genotypes in DNA repair genes Ku70 c.-1310C>G (rs2267437), Ku70 c.1781G> T (rs132788), Ku80 c.2099-2408G> A (rs3835), Ku80 c.*841G> A (rs2440) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) c.2888 + 713C> T (rs2213178) were determined by polymerase chain reaction combined with the restriction fragment length polymorphism (PCR-RFLP) technique. Mucositis was scored using the Common Terminology Criteria (CTC) for Adverse Events v.3.0 scale. The population was divided into the CTC0-2 group (CTC toxicity grade 0, 1 and 2) and the CTC3 + group (CTC toxicity grade 3 and above). Odd ratios (OR) and 95% confidence intervals (CI) were calculated using the multivariate logistic regression analysis. A significant difference in Ku70 c.1781G> T genotype distribution was observed between the CTC0-2 and CTC3 + groups for the 120 patients analyzed. The GG carriers were at higher risks for severe OM (CTC3+) compared with the TT homozygotes (OR = 3.000, 95% CI = 1.287-6.994, p = 0.011). No association was found between Ku70 (c.-1310C> G), Ku80 (c.2099-2408G> A, c.*841G> A), DNA-PKcs (c.2888 + 713 C > T) and the development of severe oral mucositis. Stratification analyses for the 50 patients treated with radiation alone further confirmed the association between the variant genotype of GG and severe OM (OR = 5.128, 95% CI = 1.183-22.238, p = 0.029). Concurrent radiochemotherapy increased the risk of severe OM for both the TT homozygotes and GG genotypes. Our study suggests that the Ku70 c.1781G> T polymorphism may be a susceptibility factor for radiation-induced oral mucositis in Chinese nasopharyngeal carcinoma patients.

DNA sequence analysis with droplet-based microfluidics

PubMed Central

Abate, Adam R.; Hung, Tony; Sperling, Ralph A.; Mary, Pascaline; Rotem, Assaf; Agresti, Jeremy J.; Weiner, Michael A.; Weitz, David A.

2014-01-01

Droplet-based microfluidic techniques can form and process micrometer scale droplets at thousands per second. Each droplet can house an individual biochemical reaction, allowing millions of reactions to be performed in minutes with small amounts of total reagent. This versatile approach has been used for engineering enzymes, quantifying concentrations of DNA in solution, and screening protein crystallization conditions. Here, we use it to read the sequences of DNA molecules with a FRET-based assay. Using probes of different sequences, we interrogate a target DNA molecule for polymorphisms. With a larger probe set, additional polymorphisms can be interrogated as well as targets of arbitrary sequence. PMID:24185402

Detection of DNA "fingerprints" of cultivated rice by hybridization with a human minisatellite DNA probe.

PubMed

Dallas, J F

1988-09-01

A human minisatellite DNA probe detects several restriction fragment length polymorphisms in cultivars of Asian and African rice. Certain fragments appear to be inherited in a Mendelian fashion and may represent unlinked loci. The hybridization patterns appear to be cultivar-specific and largely unchanged after the regeneration of plants from tissue culture. The results suggest that these regions of the rice genome may be used to generate cultivar-specific DNA fingerprints. The demonstration of similarity between a human minisatellite sequence and polymorphic regions in the rice genome suggests that such regions also occur in the genomes of many other plant species.

Polymorphic DNA microsatellite markers for forensic individual identification and parentage analyses of seven threatened species of parrots (family Psittacidae)

PubMed Central

Jan, Catherine

2016-01-01

The parrot family represents one of the bird group with the largest number of endangered species, as a result of habitat destruction and illegal trade. This illicit traffic involves the smuggling of eggs and animals, and the laundering through captive breeding facilities of wild-caught animals. Despite the huge potential of wildlife DNA forensics to determine with conclusive evidence illegal trade, current usage of DNA profiling approaches in parrots has been limited by the lack of suitable molecular markers specifically developed for the focal species and by low cross-species polymorphism. In this study, we isolated DNA microsatellite markers in seven parrot species threatened with extinction (Amazona brasiliensis, A. oratrix, A. pretrei, A. rhodocorytha, Anodorhynchus leari, Ara rubrogenys and Primolius couloni). From an enriched genomic library followed by 454 pyrosequencing, we characterized a total of 106 polymorphic microsatellite markers (mostly tetranucleotides) in the seven species and tested them across an average number of 19 individuals per species. The mean number of alleles per species and across loci varied from 6.4 to 8.3, with the mean observed heterozygosities ranging from 0.65 to 0.84. Identity and parentage exclusion probabilities were highly discriminatory. The high variability displayed by these microsatellite loci demonstrates their potential utility to perform individual genotyping and parentage analyses, in order to develop a DNA testing framework to determine illegal traffic in these threatened species. PMID:27688959

Polymorphic DNA microsatellite markers for forensic individual identification and parentage analyses of seven threatened species of parrots (family Psittacidae).

PubMed

Jan, Catherine; Fumagalli, Luca

2016-01-01

The parrot family represents one of the bird group with the largest number of endangered species, as a result of habitat destruction and illegal trade. This illicit traffic involves the smuggling of eggs and animals, and the laundering through captive breeding facilities of wild-caught animals. Despite the huge potential of wildlife DNA forensics to determine with conclusive evidence illegal trade, current usage of DNA profiling approaches in parrots has been limited by the lack of suitable molecular markers specifically developed for the focal species and by low cross-species polymorphism. In this study, we isolated DNA microsatellite markers in seven parrot species threatened with extinction (Amazona brasiliensis, A. oratrix, A. pretrei, A. rhodocorytha, Anodorhynchus leari, Ara rubrogenys and Primolius couloni). From an enriched genomic library followed by 454 pyrosequencing, we characterized a total of 106 polymorphic microsatellite markers (mostly tetranucleotides) in the seven species and tested them across an average number of 19 individuals per species. The mean number of alleles per species and across loci varied from 6.4 to 8.3, with the mean observed heterozygosities ranging from 0.65 to 0.84. Identity and parentage exclusion probabilities were highly discriminatory. The high variability displayed by these microsatellite loci demonstrates their potential utility to perform individual genotyping and parentage analyses, in order to develop a DNA testing framework to determine illegal traffic in these threatened species.

Development of a Multiplex Single Base Extension Assay for Mitochondrial DNA Haplogroup Typing

PubMed Central

Nelson, Tahnee M.; Just, Rebecca S.; Loreille, Odile; Schanfield, Moses S.; Podini, Daniele

2007-01-01

Aim To provide a screening tool to reduce time and sample consumption when attempting mtDNA haplogroup typing. Methods A single base primer extension assay was developed to enable typing, in a single reaction, of twelve mtDNA haplogroup specific polymorphisms. For validation purposes a total of 147 samples were tested including 73 samples successfully haplogroup typed using mtDNA control region (CR) sequence data, 21 samples inconclusively haplogroup typed by CR data, 20 samples previously haplogroup typed using restriction fragment length polymorphism (RFLP) analysis, and 31 samples of known ancestral origin without previous haplogroup typing. Additionally, two highly degraded human bones embalmed and buried in the early 1950s were analyzed using the single nucleotide polymorphisms (SNP) multiplex. Results When the SNP multiplex was used to type the 96 previously CR sequenced specimens, an increase in haplogroup or macrohaplogroup assignment relative to conventional CR sequence analysis was observed. The single base extension assay was also successfully used to assign a haplogroup to decades-old, embalmed skeletal remains dating to World War II. Conclusion The SNP multiplex was successfully used to obtain haplogroup status of highly degraded human bones, and demonstrated the ability to eliminate possible contributors. The SNP multiplex provides a low-cost, high throughput method for typing of mtDNA haplogroups A, B, C, D, E, F, G, H, L1/L2, L3, M, and N that could be useful for screening purposes for human identification efforts and anthropological studies. PMID:17696300

Differential DNA Methylation Patterns Are Related to Phellogen Origin and Quality of Quercus suber Cork

PubMed Central

Costa, Augusta; Roussado, Cristóvão; Gonçalves, Elsa; Costa, Rita; Graça, José; Oliveira, M. Margarida

2017-01-01

DNA methylation is thought to influence Quercus suber cork quality, which is the main constraint for its economic valorisation. However, a deep knowledge of the cytosine methylation patterns disclosing the epigenetic variability of trees with different cork quality types is totally missing. This study investigates the hypothesis that variations in DNA methylation contribute to differences in cork cellular characteristics directly related to original or traumatic phellogen activity. We used MSAPs (Methylation Sensitive Amplified Polymorphism) to assess DNA methylation patterns of cork and leaf tissues of Q. suber adult trees growing in three cork oak stands. The relationship between the detected polymorphisms and the diversity of cork quality traits was explored by a marker-trait analysis focusing on the most relevant quality characteristics. Populations differed widely in cork quality, but only slightly in degree of epigenetic differentiation. Four MSAP markers (1.3% of the total) were significantly associated with the most noteworthy quality traits: wood inclusions (nails) and porosity. This evidence supports the potential role of cytosine methylation in the modulation of differential phellogen activity either involved in localized cell death or in pore production, resulting in different cork qualities. Although, the underlying basis of the methylation polymorphism of loci affecting cork quality traits remain unclear, the disclosure of markers statistically associated with cork quality strengthens the potential role of DNA methylation in the regulation of these traits, namely at the phellogen level. PMID:28045988

Extensive 5.8S nrDNA polymorphism in Mammillaria (Cactaceae) with special reference to the identification of pseudogenic internal transcribed spacer regions.

PubMed

Harpke, Doerte; Peterson, Angela

2008-05-01

The internal transcribed spacer (ITS) region (ITS1, 5.8S rDNA, ITS2) represents the most widely applied nuclear marker in eukaryotic phylogenetics. Although this region has been assumed to evolve in concert, the number of investigations revealing high degrees of intra-individual polymorphism connected with the presence of pseudogenes has risen. The 5.8S rDNA is the most important diagnostic marker for functionality of the ITS region. In Mammillaria, intra-individual 5.8S rDNA polymorphisms of up to 36% and up to nine different types have been found. Twenty-eight of 30 cloned genomic Mammillaria sequences were identified as putative pseudogenes. For the identification of pseudogenic ITS regions, in addition to formal tests based on substitution rates, we attempted to focus on functional features of the 5.8S rDNA (5.8S motif, secondary structure). The importance of functional data for the identification of pseudogenes is outlined and discussed. The identification of pseudogenes is essential, because they may cause erroneous phylogenies and taxonomic problems.

Assessment of genome origins and genetic diversity in the genus Eleusine with DNA markers.

PubMed

Salimath, S S; de Oliveira, A C; Godwin, I D; Bennetzen, J L

1995-08-01

Finger millet (Eleusine coracana), an allotetraploid cereal, is widely cultivated in the arid and semiarid regions of the world. Three DNA marker techniques, restriction fragment length polymorphism (RFLP), randomly amplified polymorphic DNA (RAPD), and inter simple sequence repeat amplification (ISSR), were employed to analyze 22 accessions belonging to 5 species of Eleusine. An 8 probe--3 enzyme RFLP combination, 18 RAPD primers, and 6 ISSR primers, respectively, revealed 14, 10, and 26% polymorphism in 17 accessions of E. coracana from Africa and Asia. These results indicated a very low level of DNA sequence variability in the finger millets but did allow each line to be distinguished. The different Eleusine species could be easily identified by DNA marker technology and the 16% intraspecific polymorphism exhibited by the two analyzed accessions of E. floccifolia suggested a much higher level of diversity in this species than in E. coracana. Between species, E. coracana and E. indica shared the most markers, while E. indica and E. tristachya shared a considerable number of markers, indicating that these three species form a close genetic assemblage within the Eleusine. Eleusine floccifolia and E. compressa were found to be the most divergent among the species examined. Comparison of RFLP, RAPD, and ISSR technologies, in terms of the quantity and quality of data output, indicated that ISSRs are particularly promising for the analysis of plant genome diversity.

Randomly amplified polymorphic-DNA analysis for detecting genotoxic effects of Boron on maize (Zea mays L.).

PubMed

Sakcali, M Serdal; Kekec, Guzin; Uzonur, Irem; Alpsoy, Lokman; Tombuloglu, Huseyin

2015-08-01

This study was carried out to investigate the genotoxic effect of boron (B) on maize using randomly amplified polymorphic DNA (RAPD) method. Experimental design was conducted under 0, 5, 10, 25, 50, 100, 125, and 150 ppm B exposures, and physiological changes have revealed a sharp decrease in root growth rates from 28% to 85%, starting from 25 ppm to 150 ppm, respectively. RAPD-polymerase chain reaction (PCR) analysis shows that DNA alterations are clearly observed from beginning to 100 ppm. B-induced inhibition in root growth had a positive correlation with DNA alterations. Total soluble protein, root and stem lengths, and B content analysis in root and leaves encourage these results as a consequence. These preliminary findings reveal that B causes chromosomal aberration and genotoxic effects on maize. Meanwhile, usage of RAPD-PCR technique is a suitable biomarker to detect genotoxic effect of B on maize and other crops for the future. © The Author(s) 2013.

Polymorphism at codon 36 of the p53 gene.

PubMed

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.

Polymorphic Imprinting of SLC38A4 Gene in Bovine Placenta.

PubMed

Xu, Da; Zhang, Cui; Li, Junliang; Wang, Guannan; Chen, Weina; Li, Dongjie; Li, Shijie

2018-05-21

Imprinted genes are characterized by monoallelic expression that is dependent on parental origin. Comparative analysis of imprinted genes between species is a powerful tool for understanding the biological significance of genomic imprinting. The slc38a4 gene encodes a neutral amino acid transporter and is identified as imprinted in mice. In this study, the imprinting status of SLC38A4 was assessed in bovine adult tissues and placenta using a polymorphism-based approach. Results indicate that SLC38A4 is not imprinted in eight adult bovine tissues including heart, liver, spleen, lung, kidney, muscle, fat, and brain. It was interesting to note that SLC38A4 showed polymorphic status in five heterogeneous placentas, with three exhibiting paternal monoallelic expression and two exhibiting biallelic expression. Monoallelic expression of imprinted genes is generally associated with allele-specific differentially methylation regions (DMRs) of CpG islands (CGIs)-encompassed promoter; therefore, the DNA methylation statuses of three CGIs in the SLC38A4 promoter and exon 1 region were tested in three placentas (two exhibiting paternal monoallelic and one showing biallelic expression of SLC38A4) and their corresponding paternal sperms. Unexpectedly, extreme hypomethylation (< 3%) of the DNA was observed in all the three detected placentas and their corresponding paternal sperms. The absence of DMR in bovine SLC38A4 promoter region implied that DNA methylation of these three CGIs does not directly or indirectly affect the polymorphic imprinting of SLC38A4 in bovine placenta. This suggested other epigenetic features other than DNA methylation are needed in regulating the imprinting of bovine SLC38A4, which is different from that of mouse with respect to a DMR existence at the mouse's slc38a4 promoter region. Although further work is needed, this first characterization of polymorphic imprinting status of SLC38A4 in cattle placenta provides valuable information on investigating the genomic imprinting phenomenon itself.

Genetic mutation underlying orthostatic intolerance and diagnostic and therapeutic methods relating thereto

NASA Technical Reports Server (NTRS)

Blakely, Randy D. (Inventor); Robertson, David (Inventor)

2006-01-01

Isolated polynucleotide molecules and peptides encoded by these molecules are used in the analysis of human norepinephrine (NE) transporter variants, as well as in diagnostic and therapeutic applications, relating to a human NE transporter polymorphism. By analyzing genomic DNA or amplified genomic DNA, or amplified cDNA derived from mRNA, it is possible to type a human NE transporter with regard to the human NE transporter polymorphism, for example, in the context of diagnosing and treating NE transport impairments, and disorders associated with NE transport impairments, such as orthostatic intolerance.

Identification of three randomly amplified polymorphic DNA-polymerase chain reaction markers for distinguishing Asian and North American Gypsy Moths (Lepidoptera: Lymantriidae)

Treesearch

David E. Schreiber; Karen J. Garner; James M. Slavicek

1997-01-01

Gypsy moths originating in Asia have recently been introduced into North America, making it necessary to develop markers for distinguishing the Asian strain from the established North American population. We have identified 3 randomly amplified polymorphic DNA-polymerase chain reaction generated (RAPD-PCR) markers which are specific for either Asian or North American...

Identification of exotic genetic components and DNA methylation pattern analysis of three cotton introgression lines from Gossypium bickii.

PubMed

He, Shou-Pu; Sun, Jun-Ling; Zhang, Chao; Du, Xiong-Ming

2011-01-01

The impact of alien DNA fragments on plant genome has been studied in many species. However, little is known about the introgression lines of Gossypium. To study the consequences of introgression in Gossypium, we investigated 2000 genomic and 800 epigenetic sites in three typical cotton introgression lines, as well as their cultivar (Gossypium hirsutum) and wild parents (Gossypium bickii), by amplified fragment length polymorphism (AFLP) and methylation-sensitive amplified polymorphism (MSAP). The results demonstrate that an average of 0.5% of exotic DNA segments from wild cotton is transmitted into the genome of each introgression line, with the addition of other forms of genetic variation. In total, an average of 0.7% of genetic variation sites is identified in introgression lines. Simultaneously, the overall cytosine methylation level in each introgression line is very close to that of the upland cotton parent (an average of 22.6%). Further dividing patterns reveal that both hypomethylation and hypermethylation occurred in introgression lines in comparison with the upland cotton parent. Sequencing of nine methylation polymorphism fragments showed that most (7 of 9) of the methylation alternations occurred in the noncoding sequences. The molecular evidence of introgression from wild cotton into introgression lines in our study is identified by AFLP. Moreover, the causes of petal variation in introgression lines are discussed.

[Analysis of methylation-sensitive amplified polymorphism in wheat genome under the wheat leaf rust stress].

PubMed

Fu, Sheng-Jie; Wang, Hui; Feng, Li-Na; Sun, Yi; Yang, Wen-Xiang; Liu, Da-Qun

2009-03-01

Intrinsic DNA methylation pattern is an integral component of the epigenetic network in many eukaryotes. DNA methylation plays an important role in regulating gene expression in eukaryotes. Biological stress in plant provides an inherent epigenetic driving force of evolution. Study of DNA methylation patterns arising from biological stress will help us fully understand the epigenetic regulation of gene expression and DNA methylation of biological functions. The wheat near-isogenic lines TcLr19 and TcLr41 were resistant to races THTT and TKTJ, respectively, and Thatcher is compatible in the interaction with Puccinia triticina THTT and TKTJ, respectively. By means of methylation-sensitive amplified polymorphism (MSAP) analysis, the patterns of cytosine methylation in TcLr19, TcLr41, and Thatcher inoculated with P. triticina THTT and TKTJ were compared with those of the untreated samples. All the DNA fragments, each representing a recognition site cleaved by each or both of isoschizomers, were amplified using 60 pairs of selective primers. The results indicated that there was no significant difference between the challenged and unchallenged plants at DNA methylation level. However, epigenetic difference between the near-isogenic line for wheat leaf rust resistance gene Lr41 and Thatcher was present.

Investigation of paternity establishing without the putative father using hypervariable DNA probes.

PubMed

Yokoi, T; Odaira, T; Nata, M; Sagisaka, K

1990-09-01

Seven kinds of DNA probes which recognize hypervariable loci were applied for paternity test. The putative father was decreased and unavailable for the test. The two legitimate children and their mother (the deceased's wife) and the four illegitimate children and their mother (the deceased's kept mistress) were available for analysis. Paternity index of four illegitimate child was investigated. Allelic frequencies and their confidence intervals among unrelated Japanese individuals were previously reported from our laboratory, and co-dominant segregation of the polymorphism was confirmed in family studies. Cumulative paternity indices of four illegitimate children from 16 kinds of standard blood group markers were 165, 42, 0.09, and 36, respectively. On the other hand, cumulative paternity indices from 7 kinds of DNA probes are 2,363, 4,685, 57,678, and 54,994, respectively, which are 14, 113, 640, 864, and 1,509 times higher than that from standard blood group markers. The DNA analyses gave nearly conclusive evidence that the putative father was the biological father of the children. Especially, the paternity relation of the third illegitimate child could not be established without the DNA analyses. Accordingly, DNA polymorphism is considered to be informative enough for paternity test.

A functional EGF+61 polymorphism is associated with severity of obstructive sleep apnea.

PubMed

Ding, Qunli; Cao, Chao; Chen, Zhongbo; Tabusi, Mahebali; Chen, Li; Deng, Zaichun

2015-05-01

Involvement of epidermal growth factor (EGF) is reported in diseases caused by hypoxia. Its functional polymorphism may alter its transcription, affecting EGF expression, contributing to obstructive sleep apnea (OSA). The aim of this study was to investigate associations of EGF+61 polymorphism and risk of OSA. Two hundred two participants were enrolled in this case-control study. DNA was extracted from peripheral blood, and EGF 61A/G polymorphism was determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. No significant association between EGF 61 A/G polymorphism and risk of OSA was observed in any of the gene models tested (AA vs. GG: OR = 0.97, 95% CI = 0.37-2.55; P = 0.95). However, compared with GG genotype, AG genotype associated with decreased risk of severe OSA (AG vs. GG: OR = 0.32, 95% CI = 0.11-0.94). Our study showed that AG genotype has a protective effect on OSA patients against severe disease, although EGF 61A/G polymorphisms have no role on the risk of the disease. Additional large studies should further validate our findings.

Genetic alterations of hepatocellular carcinoma by random amplified polymorphic DNA analysis and cloning sequencing of tumor differential DNA fragment

PubMed Central

Xian, Zhi-Hong; Cong, Wen-Ming; Zhang, Shu-Hui; Wu, Meng-Chao

2005-01-01

AIM: To study the genetic alterations and their association with clinicopathological characteristics of hepatocellular carcinoma (HCC), and to find the tumor related DNA fragments. METHODS: DNA isolated from tumors and corresponding noncancerous liver tissues of 56 HCC patients was amplified by random amplified polymorphic DNA (RAPD) with 10 random 10-mer arbitrary primers. The RAPD bands showing obvious differences in tumor tissue DNA corresponding to that of normal tissue were separated, purified, cloned and sequenced. DNA sequences were analyzed and compared with GenBank data. RESULTS: A total of 56 cases of HCC were demonstrated to have genetic alterations, which were detected by at least one primer. The detestability of genetic alterations ranged from 20% to 70% in each case, and 17.9% to 50% in each primer. Serum HBV infection, tumor size, histological grade, tumor capsule, as well as tumor intrahepatic metastasis, might be correlated with genetic alterations on certain primers. A band with a higher intensity of 480 bp or so amplified fragments in tumor DNA relative to normal DNA could be seen in 27 of 56 tumor samples using primer 4. Sequence analysis of these fragments showed 91% homology with Homo sapiens double homeobox protein DUX10 gene. CONCLUSION: Genetic alterations are a frequent event in HCC, and tumor related DNA fragments have been found in this study, which may be associated with hepatocarcin-ogenesis. RAPD is an effective method for the identification and analysis of genetic alterations in HCC, and may provide new information for further evaluating the molecular mechanism of hepatocarcinogenesis. PMID:15996039

Fibroblast growth factor 20 (FGF20) polymorphism is a risk factor for Parkinson's disease in Chinese population.

PubMed

Pan, Jing; Li, Hui; Wang, Ying; Ma, Jian-Fang; Zhang, Jin; Wang, Gang; Liu, Jun; Wang, Xi-Jin; Xiao, Qin; Chen, Sheng-Di

2012-06-01

The etiology of Parkinson's disease (PD) is not well established. Genetic variation in fibroblast growth factor 20 (FGF20) might influence the risk of PD occurrence and development. In this study, Two DNA polymorphisms at genetic variation in FGF20, rs2720208 (C/T) and rs1721100 (C/G), were genotyped by direct sequencing in Han Chinese population, including 394 PD patients and 383 healthy controls. Statistical analyses revealed that for rs1721100 (C/G) polymorphism, there were significant differences in genotype distribution between PD and healthy-matched controls. For rs12720208 (C/T) polymorphism, there was no significant difference in genotype distribution and gender and age-related differences between PD and control group. Results in this study revealed that the rs1721100(C/G) polymorphism is a risk factor for PD in Han Chinese population, while rs12720208(C/T) polymorphism is not significantly associated with PD. Copyright © 2012 Elsevier Ltd. All rights reserved.

DNA polymorphism analysis of candidate genes for type 2 diabetes mellitus in a Mexican ethnic group.

PubMed

Flores-Martínez, S E; Islas-Andrade, S; Machorro-Lazo, M V; Revilla, M C; Juárez, R E; Mújica-López, K I; Morán-Moguel, M C; López-Cardona, M G; Sánchez-Corona, J

2004-01-01

Type 2 diabetes mellitus is a complex metabolic disorder resulting from the action and interaction of many genetic and environmental factors. It has been reported that polymorphisms in genes involved in the metabolism of glucose are associated with the susceptibility to develop type 2 diabetes mellitus. Although the risk of developing type 2 diabetes mellitus increases with age, as well as with obesity and hypertension, its prevalence and incidence are different among geographical regions and ethnic groups. In Mexico, a higher prevalence and incidence has been described in the south of the country, and differences between urban and rural communities have been observed. We studied 73 individuals from Santiago Jamiltepec, a small indigenous community from Oaxaca State, Mexico. This population has shown a high prevalence of type 2 diabetes mellitus, and the aim of this study was to analyze the relationship between the Pst I (insulin gene), Nsi I (insulin receptor gene) and Gly972Arg (insulin receptor substrate 1 gene) polymorphisms and type 2 diabetes mellitus, obesity and hypertension in this population. Clinical evaluation consisted of BMI and blood pressure measurements, and biochemical assays consisted of determination of fasting plasma insulin and glucose levels. PCR and restriction enzyme digestion analysis were applied to genomic DNA to identify the three polymorphisms. From statistical analysis carried out here, individually, the Pst I, Nsi I and Gly972Arg polymorphisms were not associated with the type 2 diabetes, obese or hypertensive phenotypes in this population. Nevertheless, there was an association between the Nsi I and Pst I polymorphisms and increased serum insulin levels.

A pipeline for the systematic identification of non-redundant full-ORF cDNAs for polymorphic and evolutionary divergent genomes: Application to the ascidian Ciona intestinalis

DOE PAGES

Gilchrist, Michael J.; Sobral, Daniel; Khoueiry, Pierre; ...

2015-05-27

Genome-wide resources, such as collections of cDNA clones encoding for complete proteins (full-ORF clones), are crucial tools for studying the evolution of gene function and genetic interactions. Non-model organisms, in particular marine organisms, provide a rich source of functional diversity. Marine organism genomes are, however, frequently highly polymorphic and encode proteins that diverge significantly from those of well-annotated model genomes. The construction of full-ORF clone collections from non-model organisms is hindered by the difficulty of predicting accurately the N-terminal ends of proteins, and distinguishing recent paralogs from highly polymorphic alleles. We also report a computational strategy that overcomes these difficulties,more » and allows for accurate gene level clustering of transcript data followed by the automated identification of full-ORFs with correct 5'- and 3'-ends. It is robust to polymorphism, includes paralog calling and does not require evolutionary proximity to well annotated model organisms. Here, we developed this pipeline for the ascidian Ciona intestinalis, a highly polymorphic member of the divergent sister group of the vertebrates, emerging as a powerful model organism to study chordate gene function, Gene Regulatory Networks and molecular mechanisms underlying human pathologies. Furthermore, using this pipeline we have generated the first full-ORF collection for a highly polymorphic marine invertebrate. It contains 19,163 full-ORF cDNA clones covering 60% of Ciona coding genes, and full-ORF orthologs for approximately half of curated human disease-associated genes.« less

Association of P53 gene polymorphism with gastric cancer in Northern Iran as a high-risk region.

PubMed

Hedayatizadeh-Omran, Akbar; Alizadeh-Navaei, Reza; Janbabaei, Ghasem; Omrani-Nava, Versa; Hasheminasab, Yahya; Amjadi, Omolbanin; Tehrani, Mohsen

2018-05-01

Gastric cancer has the fourth highest morbidity rate of all cancers worldwide. Genetic factors including alterations in oncogenes and tumor suppressor genes serve an important role in gastric cancer development and progression. The P53 gene acts as a tumor suppressor gene by regulating the cell cycle, DNA transcription and repair, apoptosis, senescence and genome stability. In addition to somatic P53 mutations in cancer development, germline polymorphisms are also involved in different malignancies. The polymorphism of P53 at codon 72 (Arg72Pro) is established as a common variant that increases susceptibility to various cancers. The present case-control study was conducted to evaluate the possible association between this P53 polymorphism and gastric cancer in the Iranian population. A total of 59 patients with gastric cancer and 59 healthy controls were enrolled in the present study. Genomic DNA was extracted from peripheral blood mononuclear cells and genotype analysis was performed using a polymerase chain reaction-based restriction fragment length polymorphism assay. Genotype frequencies did not differ significantly between the patients and controls (P=0.4); the frequencies of the three genotypes Arg/Arg, Arg/Pro and Pro/Pro in gastric cancer patients were 28.8, 49.2 and 22.0%, and in controls were 37.3, 49.2 and 13.6%. Additionally, there were no differences in genotype frequencies based on tumor location, histological differentiation or tumor stage. Based on these findings, it may be concluded that the P53 codon 72 polymorphism does not contribute to gastric cancer susceptibility in Northern Iran.

RFC-1 80G>A polymorphism in case-mother/control-mother dyads is associated with risk of nephroblastoma and neuroblastoma.

PubMed

Montalvão-de-Azevedo, Rafaela; Vasconcelos, Gisele M; Vargas, Fernando R; Thuler, Luiz Claudio; Pombo-de-Oliveira, Maria S; de Camargo, Beatriz

2015-02-01

Embryonic tumors are associated with an interruption during normal organ development; they may be related to disturbances in the folate pathway involved in DNA synthesis, methylation, and repair. Prenatal supplementation with folic acid is associated with a decreased risk of neuroblastoma, brain tumors, retinoblastoma, and nephroblastoma. The aim of this study was to investigate the association between MTHFR rs1801133 (C677T) and RFC-1 rs1051266 (G80A) genotypes with the risk of developing nephroblastoma and neuroblastoma. Case-mother/control-mother dyad study. Samples from Brazilian children with nephroblastoma (n=80), neuroblastoma (n=66), healthy controls (n=453), and their mothers (case n=93; control n=75) were analyzed. Genomic DNA was isolated from peripheral blood cells and/or buccal cells and genotyped to identify MTHFR C677T and RFC-1 G80A polymorphisms. Differences in genotype distribution between patients and controls were tested by multiple logistic regression analysis. Risk for nephroblastoma and neuroblastoma was two- to fourfold increased among children with RFC-1 polymorphisms. An increased four- to eightfold risk for neuroblastoma and nephroblastoma was seen when the child and maternal genotypes were combined. Our results suggest that mother and child RFC-1 G80A genotypes play a role on the risk of neuroblastoma and nephroblastoma since this polymorphism may impair the intracellular levels of folate, through carrying fewer folate molecules to the cell interior, and thus, the intracellular concentration is not enough to maintain regular DNA synthesis and methylation pathways.

[The association between the DNA marker rs1842993 and risk for cardioembolic stroke in the Slavic population].

PubMed

Shetova, I M; Timofeev, D Iu; Shamalov, N A; Bondarenko, E A; Slominskiĭ, P A; Limborskaia, S A; Skvortsova, V I

2012-01-01

The analysis of association between DNA markers and total stroke risk was performed in 950 Slavonic patients. Patients with cardioembolic stroke were selected for a genome-wide association study. The HUMANCYTOSNP12 v.2 microchip was used to analyze all DNA samples on a panel of 301 000 single nucleotide polymorphisms. SNP rs1842993 on chromosome 7 was found to be associated with cardioembolic stroke risk.

ERCC2, ERCC1 polymorphisms and haplotypes, cooking oil fume and lung adenocarcinoma risk in Chinese non-smoking females.

PubMed

Yin, Zhihua; Su, Meng; Li, Xuelian; Li, Mingchuan; Ma, Rui; He, Qincheng; Zhou, Baosen

2009-12-14

Excision repair cross-complementing group 1 (ERCC1) and group 2 (ERCC2) proteins play important roles in the repair of DNA damage and adducts. Single nucleotide polymorphisms (SNPs) of DNA repair genes are suspected to influence the risk of lung cancer. This study aimed to investigate the association between the ERCC2 751, 312 and ERCC1 118 polymorphisms and the risk of lung adenocarcinoma in Chinese non-smoking females. A hospital-based case-control study of 285 patients and 285 matched controls was conducted. Information concerning demographic and risk factors was obtained for each case and control by a trained interviewer. After informed consent was obtained, each person donated 10 ml blood for biomarker testing. Three polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. This study showed that the individuals with the combined ERCC2 751AC/CC genotypes were at an increased risk for lung adenocarcinoma compared with those carrying the AA genotype [adjusted odds ratios (OR) 1.64, 95% confidence interval (CI) 1.06-2.52]. The stratified analysis suggested that increased risk associated with ERCC2 751 variant genotypes (AC/CC) was more pronounced in individuals without exposure to cooking oil fume (OR 1.98, 95%CI 1.18-3.32) and those without exposure to fuel smoke (OR 2.47, 95%CI 1.46-4.18). Haplotype analysis showed that the A-G-T and C-G-C haplotypes were associated with increased risk of lung adenocarcinoma among non-smoking females (ORs were 1.43 and 2.28, 95%CIs were 1.07-1.91 and 1.34-3.89, respectively). ERCC2 751 polymorphism may be a genetic risk modifier for lung adenocarcinoma in non-smoking females in China.

MIG-seq: an effective PCR-based method for genome-wide single-nucleotide polymorphism genotyping using the next-generation sequencing platform

PubMed Central

Suyama, Yoshihisa; Matsuki, Yu

2015-01-01

Restriction-enzyme (RE)-based next-generation sequencing methods have revolutionized marker-assisted genetic studies; however, the use of REs has limited their widespread adoption, especially in field samples with low-quality DNA and/or small quantities of DNA. Here, we developed a PCR-based procedure to construct reduced representation libraries without RE digestion steps, representing de novo single-nucleotide polymorphism discovery, and its genotyping using next-generation sequencing. Using multiplexed inter-simple sequence repeat (ISSR) primers, thousands of genome-wide regions were amplified effectively from a wide variety of genomes, without prior genetic information. We demonstrated: 1) Mendelian gametic segregation of the discovered variants; 2) reproducibility of genotyping by checking its applicability for individual identification; and 3) applicability in a wide variety of species by checking standard population genetic analysis. This approach, called multiplexed ISSR genotyping by sequencing, should be applicable to many marker-assisted genetic studies with a wide range of DNA qualities and quantities. PMID:26593239

A more accurate detection of codon 72 polymorphism and LOH of the TP53 gene.

PubMed

Baccouche, Sami; Mabrouk, Imed; Said, Salem; Mosbah, Ali; Jlidi, Rachid; Gargouri, Ali

2003-01-10

The polymorphism at codon 72 of the TP53 gene has been extensively studied for its involvement in cancerogenesis and loss of heterozygosity (LOH) detection. Usually, the exon 4 of the TP53 gene is amplified by polymerase chain reaction (PCR) on DNA extracted from blood and tumor tissues, then digested by AccII. In the case of heterozygosity, the comparison of AccII profile from blood and tumor DNA PCR products allowed the identification of a potential LOH in the TP53 locus. This method can be hindered by a partial AccII digestion and/or DNA contamination of non-tumor cells. To circumvent these problems, we have developed a new approach by using the AccII restriction site between exon 4 and exon 6. The PCR amplification of exon 4-6, followed by AccII digestion allowed us to detect without ambiguity any LOH case.

Authentication of Botanical Origin in Herbal Teas by Plastid Noncoding DNA Length Polymorphisms.

PubMed

Uncu, Ali Tevfik; Uncu, Ayse Ozgur; Frary, Anne; Doganlar, Sami

2015-07-01

The aim of this study was to develop a DNA barcode assay to authenticate the botanical origin of herbal teas. To reach this aim, we tested the efficiency of a PCR-capillary electrophoresis (PCR-CE) approach on commercial herbal tea samples using two noncoding plastid barcodes, the trnL intron and the intergenic spacer between trnL and trnF. Barcode DNA length polymorphisms proved successful in authenticating the species origin of herbal teas. We verified the validity of our approach by sequencing species-specific barcode amplicons from herbal tea samples. Moreover, we displayed the utility of PCR-CE assays coupled with sequencing to identify the origin of undeclared plant material in herbal tea samples. The PCR-CE assays proposed in this work can be applied as routine tests for the verification of botanical origin in herbal teas and can be extended to authenticate all types of herbal foodstuffs.

Lactobacillus nantensis sp. nov., isolated from French wheat sourdough.

PubMed

Valcheva, Rosica; Ferchichi, Mounir F; Korakli, Maher; Ivanova, Iskra; Gänzle, Michael G; Vogel, Rudi F; Prévost, Hervé; Onno, Bernard; Dousset, Xavier

2006-03-01

A polyphasic taxonomic study of the bacterial flora isolated from traditional French wheat sourdough, using phenotypic characterization and phylogenetic as well as genetic methods, revealed a consistent group of isolates that could not be assigned to any recognized species. These results were confirmed by randomly amplified polymorphic DNA and amplified fragment length polymorphism fingerprinting analyses. Cells were Gram-positive, homofermentative rods. Comparative 16S rRNA gene sequence analysis of the representative strain LP33T indicated that these strains belong to the genus Lactobacillus and that they formed a branch distinct from their closest relatives Lactobacillus farciminis, Lactobacillus alimentarius, Lactobacillus paralimentarius and Lactobacillus mindensis. DNA-DNA reassociation experiments with the three phylogenetically closest Lactobacillus species confirmed that LP33T (= DSM 16982T = CIP 108546T = TMW 1.1265T) represents the type strain of a novel species, for which the name Lactobacillus nantensis sp. nov. is proposed.

Genetic relatedness between oral and intestinal isolates of Porphyromonas endodontalis by analysis of random amplified polymorphic DNA.

PubMed

Gonçalves, R B; Väisänen, M L; Van Steenbergen, T J; Sundqvist, G; Mouton, C

1999-01-01

Genomic fingerprints from the DNA of 27 strains of Porphyromonas endodontalis from diverse clinical and geographic origins were generated as random amplified polymorphic DNA (RAPD) using the technique of PCR amplification with a single primer of arbitrary sequence. Cluster analysis of the combined RAPD data obtained with three selected 9- or 10-mer-long primers identified 25 distinct RAPD types which clustered as three main groups identifying three genogroups. Genogroups I and II included exclusively P. endodontalis isolates of oral origin, while 7/9 human intestinal strains of genogroup III which linked at a similarity level of 52% constituted the most homogeneous group in our study. Genotypic diversity within P. endodontalis, as shown by RAPD analysis, suggests that the taxon is composed of two oral genogroups and one intestinal genogroup. This hypothesis remains to be confirmed.

Environmental polycyclic aromatic hydrocarbon (PAH) exposure and DNA damage in Mexican children.

PubMed

Sánchez-Guerra, Marco; Pelallo-Martínez, Nadia; Díaz-Barriga, Fernando; Rothenberg, Stephen J; Hernández-Cadena, Leticia; Faugeron, Sylvain; Oropeza-Hernández, Luis F; Guaderrama-Díaz, Margarita; Quintanilla-Vega, Betzabet

2012-02-18

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants presenting a public health risk, particularly to children, a vulnerable population. PAHs have genotoxic and carcinogenic properties, which depend on their metabolism. Many enzymes involved in PAH metabolism, including CYP1A1, CYP1B1, GSTM and GSTT are polymorphic, which may modulate the activation/deactivation of these compounds. We evaluated PAH exposure and DNA damage in children living in the vicinity of the main petrochemical complex located in the Gulf of Mexico, and explored the modulation by genetic polymorphisms of PAH excretion and related DNA damage. The participants (n=82) were children aged 6-10y attending schools near the industrial area. Urinary 1-hydroxypyrene (1-OHP; a biomarker of PAH exposure) was determined by reverse-phase-HPLC; DNA damage by the comet assay (Olive Tail Moment (OTM) parameter); CYP1A1*2C and CYP1B1*3 polymorphisms by real time-PCR; and GSTM1*0 and GSTT1*0 by multiplex PCR. The median value of 1-OHP was 0.37μmol/mol creatinine; 59% of children had higher 1-OHP concentrations than those reported in environmentally exposed adults (0.24μmol/mol creatinine). A stratified analysis showed increased DNA damage in children with 1-OHP concentrations greater than the median value. We observed higher 1-OHP concentrations in children with CYP1A1*2C or GSTM1*0 polymorphisms, and a positive influence of CYP1A1*2C on OTM values in children with the highest PAH exposure. The data indicate that children living in the surroundings of petrochemical industrial areas are exposed to high PAH levels, contributing to DNA damage and suggesting an increased health risk; furthermore, data suggest that polymorphisms affecting activation enzymes may modulate PAH metabolism and toxicity. Copyright © 2012 Elsevier B.V. All rights reserved.

Traceability of plant contribution in olive oil by amplified fragment length polymorphisms.

PubMed

Pafundo, Simona; Agrimonti, Caterina; Marmiroli, Nelson

2005-09-07

Application of DNA molecular markers to traceability of foods is thought to bring new benefit to consumer's protection. Even in a complex matrix such as olive oil, DNA could be traced with PCR markers such as the amplified fragment length polymorphisms (AFLPs). In this work, fluorescent AFLPs were optimized for the characterization of olive oil DNA, to obtain highly reproducible, high-quality fingerprints, testing different parameters: the concentrations of dNTPs and labeled primer, the kind of Taq DNA polymerase and thermal cycler, and the quantity of DNA employed. It was found that correspondence of fingerprinting by comparing results in oils and in plants was close to 70% and that the DNA extraction from olive oil was the limiting step for the reliability of AFLP profiles, due to the complex matrix analyzed.

Single Nucleotide Polymorphism Analysis of European Archaeological M. leprae DNA

PubMed Central

Watson, Claire L.; Lockwood, Diana N. J.

2009-01-01

Background Leprosy was common in Europe eight to twelve centuries ago but molecular confirmation of this has been lacking. We have extracted M. leprae ancient DNA (aDNA) from medieval bones and single nucleotide polymorphism (SNP) typed the DNA, this provides insight into the pattern of leprosy transmission in Europe and may assist in the understanding of M. leprae evolution. Methods and Findings Skeletons have been exhumed from 3 European countries (the United Kingdom, Denmark and Croatia) and are dated around the medieval period (476 to 1350 A.D.). we tested for the presence of 3 previously identified single nucleotide polymorphisms (SNPs) in 10 aDNA extractions. M. leprae aDNA was extracted from 6 of the 10 bone samples. SNP analysis of these 6 extractions were compared to previously analysed European SNP data using the same PCR assays and were found to be the same. Testing for the presence of SNPs in M. leprae DNA extracted from ancient bone samples is a novel approach to analysing European M. leprae DNA and the findings concur with the previously published data that European M. leprae strains fall in to one group (SNP group 3). Conclusions These findings support the suggestion that the M. leprae genome is extremely stable and show that archaeological M. leprae DNA can be analysed to gain detailed information about the genotypic make-up of European leprosy, which may assist in the understanding of leprosy transmission worldwide. PMID:19847306

Analysis of cytotoxic T lymphocyte associated antigen 4 gene polymorphisms in patients with ulcerative colitis.

PubMed

Lankarani, Kamran B; Karbasi, Ashraf; Kalantari, Tahereh; Yarmohammadi, Hooman; Saberi-Firoozi, Mehdi; Alizadeh-Naeeni, Mahvash; Taghavi, Ali R; Fattahi, Mahammad R; Ghaderi, Abbas

2006-02-01

Ulcerative colitis (UC) is a multifactorial disease associated with dysregulated immunity. Recently, cytotoxic T lymphocyte associated antigen 4 (CTLA-4) gene polymorphisms have been reported in association with several autoimmune diseases in several populations. In the present study, the possible implication of the CTLA-4 gene as a risk factor for UC in the Iranian population was investigated. One hundred UC patients and 100 healthy subjects were studied. CTLA-4 exon 1 position 49 (A/G: codon 17: Thr/Ala) polymorphisms were investigated by polymerase chain reaction single strand confirmation polymorphism method. Four of the patients and one of the healthy controls were excluded from the study because of incomplete DNA extraction. The allele frequencies of A and G in 96 patients (A: 66.1%; G: 33.9%) were not significantly different from the 99 control subjects (A: 63.1%; G: 36.9%, P > 0.05). No significant differences in the distribution of genotype frequencies were observed between A + 49G gene polymorphisms and UC in the Iranian population (P > 0.05). CTLA-4 polymorphism is not associated with UC in the Iranian population.

Association of the widespread A149P hereditary fructose intolerance mutation with newly identified sequence polymorphisms in the aldolase B gene

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

Brooks, C.C.; Tolan, D.R.

1993-04-01

Hereditary fructose intolerance (HFI) is a potentially fatal autosomal recessive disease resulting from the catalytic deficiency of fructose 1-phosphate aldolase (aldolase B) in fructose-metabolizing tissues. The A149P mutation in exon 5 of the aldolase B gene, located on chromosome 9q2l.3-q22.2, is widespread and the most common HFI mutation, accounting for 57% of HFI chromosomes. The possible origin of this mutation was studied by linkage to polymorphisms within the aldolase B gene. DNA fragments of the aldolase B gene containing the polymorphic marker loci from HFI patients homozygous for the A149P allele were amplified by PCR. Absolute linkage to a commonmore » Pvull RFLP allele was observed in 10 A149P homozygotes. In a more informative study, highly heterozygous polymorphisms were detected by direct sequence determination of a PCR-amplified aldolase B gene fragment. Two two-allele, single-base-pair polymorphisms, themselves in absolute linkage disequilibrium, in intron 8 (C at nucleotide 84 and A at nucleotide 105, or T at 84 and G at 105) of the aldolase B gene were identified. Mendelian segregation of these polymorphisms was confirmed in three families. Allele-specific oligonucleotide (ASO) hybridizations with probes for both sequence polymorphisms showed that 47% of 32 unrelated individuals were heterozygous at these loci; the calculated PIC value was .37. Finally, ASO hybridizations of PCR-amplified DNA from 15 HFI patients homozygous for the A149P allele with probes for these sequence polymorphisms revealed absolute linkage disequilibrium between the A149P mutation and the 84T/105G allele. These results are consistent with a single origin of the A149P allele and subsequent spread by genetic drift. 32 refs., 4 figs., 3 tabs.« less

The first report of prion-related protein gene (PRNT) polymorphisms in goat.

PubMed

Kim, Yong-Chan; Jeong, Byung-Hoon

2017-06-01

Prion protein is encoded by the prion protein gene (PRNP). Polymorphisms of several members of the prion gene family have shown association with prion diseases in several species. Recent studies on a novel member of the prion gene family in rams have shown that prion-related protein gene (PRNT) has a linkage with codon 26 of prion-like protein (PRND). In a previous study, codon 26 polymorphism of PRND has shown connection with PRNP haplotype which is strongly associated with scrapie vulnerability. In addition, the genotype of a single nucleotide polymorphism (SNP) at codon 26 of PRND is related to fertilisation capacity. These findings necessitate studies on the SNP of PRNT gene which is connected with PRND. In goat, several polymorphism studies have been performed for PRNP, PRND, and shadow of prion protein gene (SPRN). However, polymorphism on PRNT has not been reported. Hence, the objective of this study was to determine the genotype and allelic distribution of SNPs of PRNT in 238 Korean native goats and compare PRNT DNA sequences between Korean native goats and several ruminant species. A total of five SNPs, including PRNT c.-114G > T, PRNT c.-58A > G in the upstream of PRNT gene, PRNT c.71C > T (p.Ala24Val) and PRNT c.102G > A in the open reading frame (ORF) and c.321C > T in the downstream of PRNT gene, were found in this study. All five SNPs of caprine PRNT gene in Korean native goat are in complete linkage disequilibrium (LD) with a D' value of 1.0. Interestingly, comparative sequence analysis of the PRNT gene revealed five mismatches between DNA sequences of Korean native goats and those of goats deposited in the GenBank. Korean native black goats also showed 5 mismatches in PRNT ORF with cattle. To the best of our knowledge, this is the first genetic research of the PRNT gene in goat.

Methylation-sensitive amplification polymorphism in date palms (Phoenix dactylifera L.) and their off-shoots.

PubMed

Fang, J-G; Chao, C T

2007-07-01

DNA methylation plays an important role in the regulation of gene expression in eukaryotes. In this study, the extent and patterns of DNA methylation were assessed in date palm mother-plants and their off-shoots using the methylation-sensitive amplified polymorphism (MSAP) technique. Three types of bands were generated using 12 pairs of primers. Type I were present in both ECOR I + HPA II and ECOR I + MSP I lanes; type II were present in ECOR I + HPA II lanes, but not in ECOR I + MSP I lanes; and type III bands were present in ECOR I + MSP I lanes, but not in ECOR I + HPA II lanes. The total numbers of these three types of bands were 782, 55, and 34, respectively. Among these three types of bands, the polymorphic bands were, respectively, 37, 10, and 0. The distribution of polymorphic bands among mother-plants and off-shoots suggests the methylation variation was present in both the mother-plants and off-shoots. Forty- four out of these 47 polymorphic bands show clear difference between mother-plant and off-shoots: 38 were present only in off-shoots and 6 in both mother-plants and off-shoots. Compared to methylation status in mother-plants, the methylation variation during off-shoot growth of date palm can be characterized as a process involving primarily de-methylation. Hypomethylation of DNA in off-shoots, compared with mother-plants, reflects the marked expression of this molecular feature, which may be related to gene expression during off-shoot development. The methylation or de-methylation status of specific loci in the mother-plants and their off-shoots were probably random events.

Rapid single nucleotide polymorphism detection for personalized medicine applications using planar waveguide fluorescence sensors

NASA Astrophysics Data System (ADS)

Herron, James N.; Tolley, Samuel E.; Smith, Richard; Christensen, Douglas A.

2006-02-01

Personalized medicine is an emerging field in which clinical diagnostics information about a patient's genotype or phenotype is used to optimize his/her pharmacotherapy. This article evaluates whether planar waveguide fluorescent sensors are suitable for determining such information from patient testing in point-of-care (POC) settings. The model system was Long QT Syndrome, a congenital disease associated with single nucleotide polymorphisms (SNPs) in genes encoding for cardiac ion channels. Three different SNP assay formats were examined: DNA/DNA hybridization, DNA/PNA hybridization (PNA: "peptide nucleic acid"), and single base extension (SBEX). Although DNA/DNA hybridization produced a strong intensity-time response for both wildtype and SNP analytes in a 5-min assay at 32°C, their hybridization rates differed by only 32.7%, which was insufficient for clinical decision-making. Much better differentiation of the two rates was observed at 53°C, where the wildtype's hybridization rate was two-thirds of its maximum value, while that of the SNP was essentially zero. Such all-or-nothing resolution would be adequate for clinical decision-making; however, the elevated temperature and precise temperature control would be hard to achieve in a POC setting. Results from DNA/PNA hybridization studies were more promising. Nearly 20-fold discrimination between wildtype and SNP hybridization rates was observed in a 5-min assay at 30°C, although the low ionic strength conditions required necessitated a de-salting step between sample preparation and SNP detection. SBEX was the most promising of the three, determining the absolute identity of the suspected polymorphism in a 5-min assay at 40°C.

Mitochondrial bioenergetics and drug-induced toxicity in a panel of mouse embryonic fibroblasts with mitochondrial DNA single nucleotide polymorphisms

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

Pereira, Claudia V.; Oliveira, Paulo J.; Will, Yvonne

2012-10-15

Mitochondrial DNA (mtDNA) variations including single nucleotide polymorphisms (SNPs) have been proposed to be involved in idiosyncratic drug reactions. However, current in vitro and in vivo models lack the genetic diversity seen in the human population. Our hypothesis is that different cell strains with distinct mtDNA SNPs may have different mitochondrial bioenergetic profiles and may therefore vary in their response to drug-induced toxicity. Therefore, we used an in vitro system composed of four strains of mouse embryonic fibroblasts (MEFs) with mtDNA polymorphisms. We sequenced mtDNA from embryonic fibroblasts isolated from four mouse strains, C57BL/6J, MOLF/EiJ, CZECHII/EiJ and PERA/EiJ, with themore » latter two being sequenced for the first time. The bioenergetic profile of the four strains of MEFs was investigated at both passages 3 and 10. Our results showed that there were clear differences among the four strains of MEFs at both passages, with CZECHII/EiJ having a lower mitochondrial robustness when compared to C57BL/6J, followed by MOLF/EiJ and PERA/EiJ. Seven drugs known to impair mitochondrial function were tested for their effect on the ATP content of the four strains of MEFs in both glucose- and galactose-containing media. Our results showed that there were strain-dependent differences in the response to some of the drugs. We propose that this model is a useful starting point to study compounds that may cause mitochondrial off-target toxicity in early stages of drug development, thus decreasing the number of experimental animals used. -- Highlights: ► mtDNA SNPs may be linked to individual predisposition to drug-induced toxicity. ► CZECHII/EiJ and PERA/EiJ mtDNA was sequenced for the first time in this study. ► Strain-dependent mitochondrial capacity differences were measured. ► Strain-dependent differences in response to mitochondrial toxicants were observed.« less

Multiplex Allele-Specific Amplification from Whole Blood for Detecting Multiple Polymorphisms Simultaneously

PubMed Central

Zhu, Jianjie; Chen, Lanxin; Mao, Yong; Zhou, Huan

2013-01-01

Allele-specific amplification on the basis of polymerase chain reaction (PCR) has been widely used for single-nucleotide polymorphism (SNP) genotyping. However, the extraction of PCR-compatible genomic DNA from whole blood is usually required. This process is complicated and tedious, and is prone to cause cross-contamination between samples. To facilitate direct PCR amplification from whole blood without the extraction of genomic DNA, we optimized the pH value of PCR solution and the concentrations of magnesium ions and facilitator glycerol. Then, we developed multiplex allele-specific amplifications from whole blood and applied them to a case–control study. In this study, we successfully established triplex, five-plex, and eight-plex allele-specific amplifications from whole blood for determining the distribution of genotypes and alleles of 14 polymorphisms in 97 gastric cancer patients and 141 healthy controls. Statistical analysis results showed significant association of SNPs rs9344, rs1799931, and rs1800629 with the risk of gastric cancer. This method is accurate, time-saving, cost-effective, and easy-to-do, especially suitable for clinical prediction of disease susceptibility. PMID:23072573

Genetic characterization of hybridization and introgression between anadromous rainbow trout (oncorhynchus mykiss irideus) and coastal cutthroat trout (o. clarki clarki)

USGS Publications Warehouse

Young, W.P.; Ostberg, C.O.; Keim, P.; Thorgaard, G.H.

2001-01-01

Interspecific hybridization represents a dynamic evolutionary phenomenon and major conservation problem in salmonid fishes. In this study we used amplified fragment length polymorphisms (AFLP) and mitochondrial DNA (mtDNA) markers to describe the extent and characterize the pattern of hybridization and introgression between coastal rainbow trout (Oncorhynchus mykiss irideus) and coastal cutthroat trout (O. clarki clarki). Hybrid individuals were initially identified using principle coordinate analysis of 133 polymorphic AFLP markers. Subsequent analysis using 23 diagnostic AFLP markers revealed the presence of F1, rainbow trout backcross, cutthroat trout backcross and later-generation hybrids. mtDNA analysis demonstrated equal numbers of F1 hybrids with rainbow and cutthroat trout mtDNA indicating reciprocal mating of the parental types. In contrast, rainbow and cutthroat trout backcross hybrids always exhibited the mtDNA from the recurrent parent, indicating a male hybrid mating with a pure female. This study illustrates the usefulness of the AFLP technique for generating large numbers of species diagnostic markers. The pattern of hybridization raises many questions concerning the existence and action of reproductive isolating mechanisms between these two species. Our findings are consistent with the hypothesis that introgression between anadromous populations of coastal rainbow and coastal cutthroat trout is limited by an environment-dependent reduction in hybrid fitness.

[Effect of BSA on random amplified polymorphic DNA (RAPD) in plants].

PubMed

Bian, Cai-Miao; Li, Jun-Min; Jin, Ze-Xin; Ge, Ming-Ju

2002-05-01

Using Metasequoia glyptostroboides and Heptacodium miconioides DNA as templates,the effect of bovine serum albumin (BSA) on RAPD in plants was studied. The results showed that suitable concentrations of BSA used in Metasequoia glyptostroboides and Heptacodium miconioides RAPD were different, which were 0.6 microg/microl and 1 microg/microl, respectively. The inhibition of acetylated BSA on the amplification of plant RAPD could be relieved by BSA. BSA could reduce the dosage of Taq DNA polymerase.

Interaction of methylation-related genetic variants with circulating fatty acids on plasma lipids: a meta-analysis of 7 studies & methylation analysis of 3 studies in the Cohorts for Heart & Aging Research

USDA-ARS?s Scientific Manuscript database

Background: DNA methylation is influenced by diet and single nucleotide polymorphisms (SNPs), and methylation modulates gene expression. Objective: We aimed to explore whether the gene-by-diet interactions on blood lipids act through DNA methylation. Design: We selected 7 SNPs on the basis of predic...

Pharmacogenetics of human 3'-phosphoadenosine 5'-phosphosulfate synthetase 1 (PAPSS1): gene resequencing, sequence variation, and functional genomics.

PubMed

Xu, Zhen-Hua; Thomae, Bianca A; Eckloff, Bruce W; Wieben, Eric D; Weinshilboum, Richard M

2003-06-01

3'-Phosphoadenosine 5'-phosphosulfate (PAPS) is the high-energy "sulfate donor" for reactions catalyzed by sulfotransferase (SULT) enzymes. The strict requirement of SULTs for PAPS suggests that PAPS synthesis might influence the rate of sulfate conjugation. In humans, PAPS is synthesized from ATP and SO(4)(2-) by two isoforms of PAPS synthetase (PAPSS): PAPSS1 and PAPSS2. As a step toward pharmacogenetic studies, we have resequenced the entire coding sequence of the human PAPSS1 gene, including exon-intron splice junctions, using DNA samples from 60 Caucasian-American and 58 African-American subjects. Twenty-one genetic polymorphisms were observed-1 insertion-deletion event and 20 single nucleotide polymorphisms (SNPs)-including two non-synonymous coding SNPs (cSNPs) that altered the following amino acids: Arg333Cys and Glu531Gln. Twelve pairs of these polymorphisms were tightly linked, and a total of twelve unequivocal haplotypes could be identified-two that were common to both ethnic groups and ten that were ethnic-specific. The Arg333Cys polymorphism, with an allele frequency of 2.5%, was observed only in DNA samples from Caucasian subjects. The Glu531Gln polymorphism was rare, with only a single copy of that allele in a DNA sample from an African-American subject. Transient expression in mammalian cells showed that neither of the non-synonymous cSNPs resulted in a change in the basal level of enzyme activity measured under optimal assay conditions. However, the Glu531Gln polymorphism altered the substrate kinetic properties of the enzyme. The Gln531 variant allozyme had a 5-fold higher K(m) value for SO(4)(2-) than did the wild-type allozyme and displayed monophasic kinetics for Na(2)SO(4). The wild-type allozyme (Glu531) showed biphasic kinetics for that substrate. These observations represent a step toward testing the hypothesis that genetic variation in PAPS synthesis catalyzed by PAPSS1 might alter in vivo sulfate conjugation.

Ribosomal DNA intergenic spacer sequence in foxtail millet, Setaria italica (L.) P. Beauv. and its characterization and application to typing of foxtail millet landraces.

PubMed

Fukunaga, Kenji; Ichitani, Katsuyuki; Taura, Satoru; Sato, Muneharu; Kawase, Makoto

2005-02-01

We determined the sequence of ribosomal DNA (rDNA) intergenic spacer (IGS) of foxtail millet isolated in our previous study, and identified subrepeats in the polymorphic region. We also developed a PCR-based method for identifying rDNA types based on sequence information and assessed 153 accessions of foxtail millet. Results were congruent with our previous works. This study provides new findings regarding the geographical distribution of rDNA variants. This new method facilitates analyses of numerous foxtail millet accessions. It is helpful for typing of foxtail millet germplasms and elucidating the evolution of this millet.

[Application of multiple polymorphism genetic markers in determination of half sibling sharing a same mother].

PubMed

Que, Ting-zhi; Zhao, Shu-min; Li, Cheng-tao

2010-08-01

Determination strategies for half sibling sharing a same mother were investigated through the detection of autosomal and X-chromosomal STR (X-STR) loci and polymorphisms on hypervariable (HV) region of mitochondrial DNA (mtDNA). Genomic DNA were extracted from blood stain samples of the 3 full siblings and one dubious half sibling sharing the same mother with them. Fifteen autosomal STR loci were genotyped by Sinofiler kit, and 19 X-STR loci were genotyped by Mentype Argus X-8 kit and 16 plex in-house system. Polymorphisms of mtDNA HV-I and HV-II were also detected with sequencing technology. Full sibling relationship between the dubious half sibling and each of the 3 full siblings were excluded based on the results of autosomal STR genotyping and calculation of full sibling index (FSI) and half sibling index (HIS). Results of sequencing for mtDNA HV-I and HV-II showed that all of the 4 samples came from a same maternal line. X-STR genotyping results determined that the dubious half sibling shared a same mother with the 3 full siblings. It is reliable to combine three different genotyping technologies including autosomal STR, X-STR and sequencing of mtDNA HV-I and HV-II for determination of half sibling sharing a same mother.

Combination of DNA-based and conventional methods to detect human leukocyte antigen polymorphism and its use for paternity testing.

PubMed

Kereszturya, László; Rajczya, Katalin; Lászikb, András; Gyódia, Eva; Pénzes, Mária; Falus, András; Petrányia, Gyõzõ G

2002-03-01

In cases of disputed paternity, the scientific goal is to promote either the exclusion of a falsely accused man or the affiliation of the alleged father. Until now, in addition to anthropologic characteristics, the determination of genetic markers included human leukocyte antigen gene variants; erythrocyte antigens and serum proteins were used for that reason. Recombinant DNA techniques provided a new set of highly variable genetic markers based on DNA nucleotide sequence polymorphism. From the practical standpoint, the application of these techniques to paternity testing provides greater versatility than do conventional genetic marker systems. The use of methods to detect the polymorphism of human leukocyte antigen loci significantly increases the chance of validation of ambiguous results in paternity testing. The outcome of 2384 paternity cases investigated by serologic and/or DNA-based human leukocyte antigen typing was statistically analyzed. Different cases solved by DNA typing are presented involving cases with one or two accused men, exclusions and nonexclusions, and tests of the paternity of a deceased man. The results provide evidence for the advantage of the combined application of various techniques in forensic diagnostics and emphasizes the outstanding possibilities of DNA-based assays. Representative examples demonstrate the strength of combined techniques in paternity testing.

Varietal Tracing of Virgin Olive Oils Based on Plastid DNA Variation Profiling

PubMed Central

Pérez-Jiménez, Marga; Besnard, Guillaume; Dorado, Gabriel; Hernandez, Pilar

2013-01-01

Olive oil traceability remains a challenge nowadays. DNA analysis is the preferred approach to an effective varietal identification, without any environmental influence. Specifically, olive organelle genomics is the most promising approach for setting up a suitable set of markers as they would not interfere with the pollinator variety DNA traces. Unfortunately, plastid DNA (cpDNA) variation of the cultivated olive has been reported to be low. This feature could be a limitation for the use of cpDNA polymorphisms in forensic analyses or oil traceability, but rare cpDNA haplotypes may be useful as they can help to efficiently discriminate some varieties. Recently, the sequencing of olive plastid genomes has allowed the generation of novel markers. In this study, the performance of cpDNA markers on olive oil matrices, and their applicability on commercial Protected Designation of Origin (PDO) oils were assessed. By using a combination of nine plastid loci (including multi-state microsatellites and short indels), it is possible to fingerprint six haplotypes (in 17 Spanish olive varieties), which can discriminate high-value commercialized cultivars with PDO. In particular, a rare haplotype was detected in genotypes used to produce a regional high-value commercial oil. We conclude that plastid haplotypes can help oil traceability in commercial PDO oils and set up an experimental methodology suitable for organelle polymorphism detection in the complex olive oil matrices. PMID:23950947

Multiplex APLP System for High-Resolution Haplogrouping of Extremely Degraded East-Asian Mitochondrial DNAs

PubMed Central

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

Quizalofop-p-ethyl-induced phytotoxicity and genotoxicity in Lemna minor and Lemna gibba.

PubMed

Doganlar, Zeynep B

2012-01-01

In this study, the effects of the herbicide, quizalofop-p-ethyl, on pigment contents (total chlorophyll, chlorophyll a/b, carotenoid), antioxidant enzyme [superoxide dismutase (SOD) and guaiacol peroxidase (POD)] activities, lipid peroxidation product (malondialdehyde: MDA) and DNA profiles were investigated in Lemna gibba and Lemna minor. Laboratory-acclimatized plants were treated with quizalofop-p-ethyl at 31.375, 62.75, 125 and 250 mg L(-1) for 24 and 96 h. It was determined that quizalofop-p-ethyl affected both the physiological status and the DNA profiles of L. gibba and L. minor. The photosynthetic pigments of L. gibba were more sensitive to the herbicide than were those of L. minor at both treatment times. SOD and POD activities were elevated in both plants at 24 h. However at 96 h, SOD activity decreased in L. minor and had irregular changes in L. gibba.. Significant increases in the amounts of MDA were observed in L. gibba, whereas the levels of this compound decreased in L. minor at 24 and 96 h. Polymorphism in DNA profiles was determined using the Random Amplified Polymorphic DNA (RAPD) technique. Four primers were used for scoring (appearance and disappearance of DNA polymorphic bands), and equally weighted maximum parsimony analyses were performed. Fewer differences were observed at 24 h, and more new bands were observed at 96 h in L. gibba. The RAPD profiles of L. minor produced by all of the primers were slightly less affected by the herbicide treatment than were those of L. gibba.

Multiplex APLP System for High-Resolution Haplogrouping of Extremely Degraded East-Asian Mitochondrial DNAs.

PubMed

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.

The Science and Issues of Human DNA Polymorphisms: A Training Workshop for High School Biology Teachers

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

Evaluation of genetic diversity in Chinese kale (Brassica oleracea L. var. alboglabra Bailey) by using rapid amplified polymorphic DNA and sequence-related amplified polymorphism markers.

PubMed

Zhang, J; Zhang, L G

2014-02-14

Chinese kale is an original Chinese vegetable of the Cruciferae family. To select suitable parents for hybrid breeding, we thoroughly analyzed the genetic diversity of Chinese kale. Random amplified polymorphic DNA (RAPD) and sequence-related amplified polymorphism (SRAP) molecular markers were used to evaluate the genetic diversity across 21 Chinese kale accessions from AVRDC and Guangzhou in China. A total of 104 bands were detected by 11 RAPD primers, of which 66 (63.5%) were polymorphic, and 229 polymorphic bands (68.4%) were observed in 335 bands amplified by 17 SRAP primer combinations. The dendrogram showed the grouping of the 21 accessions into 4 main clusters based on RAPD data, and into 6 clusters based on SRAP and combined data (RAPD + SRAP). The clustering of accessions based on SRAP data was consistent with petal colors. The Mantel test indicated a poor fit for the RAPD and SRAP data (r = 0.16). These results have an important implication for Chinese kale germplasm characterization and improvement.

High-coverage methylation data of a gene model before and after DNA damage and homologous repair.

PubMed

Pezone, Antonio; Russo, Giusi; Tramontano, Alfonso; Florio, Ermanno; Scala, Giovanni; Landi, Rosaria; Zuchegna, Candida; Romano, Antonella; Chiariotti, Lorenzo; Muller, Mark T; Gottesman, Max E; Porcellini, Antonio; Avvedimento, Enrico V

2017-04-11

Genome-wide methylation analysis is limited by its low coverage and the inability to detect single variants below 10%. Quantitative analysis provides accurate information on the extent of methylation of single CpG dinucleotide, but it does not measure the actual polymorphism of the methylation profiles of single molecules. To understand the polymorphism of DNA methylation and to decode the methylation signatures before and after DNA damage and repair, we have deep sequenced in bisulfite-treated DNA a reporter gene undergoing site-specific DNA damage and homologous repair. In this paper, we provide information on the data generation, the rationale for the experiments and the type of assays used, such as cytofluorimetry and immunoblot data derived during a previous work published in Scientific Reports, describing the methylation and expression changes of a model gene (GFP) before and after formation of a double-strand break and repair by homologous-recombination or non-homologous-end-joining. These data provide: 1) a reference for the analysis of methylation polymorphism at selected loci in complex cell populations; 2) a platform and the tools to compare transcription and methylation profiles.

High-coverage methylation data of a gene model before and after DNA damage and homologous repair

PubMed Central

Pezone, Antonio; Russo, Giusi; Tramontano, Alfonso; Florio, Ermanno; Scala, Giovanni; Landi, Rosaria; Zuchegna, Candida; Romano, Antonella; Chiariotti, Lorenzo; Muller, Mark T.; Gottesman, Max E.; Porcellini, Antonio; Avvedimento, Enrico V.

2017-01-01

Genome-wide methylation analysis is limited by its low coverage and the inability to detect single variants below 10%. Quantitative analysis provides accurate information on the extent of methylation of single CpG dinucleotide, but it does not measure the actual polymorphism of the methylation profiles of single molecules. To understand the polymorphism of DNA methylation and to decode the methylation signatures before and after DNA damage and repair, we have deep sequenced in bisulfite-treated DNA a reporter gene undergoing site-specific DNA damage and homologous repair. In this paper, we provide information on the data generation, the rationale for the experiments and the type of assays used, such as cytofluorimetry and immunoblot data derived during a previous work published in Scientific Reports, describing the methylation and expression changes of a model gene (GFP) before and after formation of a double-strand break and repair by homologous-recombination or non-homologous-end-joining. These data provide: 1) a reference for the analysis of methylation polymorphism at selected loci in complex cell populations; 2) a platform and the tools to compare transcription and methylation profiles. PMID:28398335

Lack of correlation between p53 codon 72 polymorphism and anal cancer risk

PubMed Central

Contu, Simone S; Agnes, Grasiela; Damin, Andrea P; Contu, Paulo C; Rosito, Mário A; Alexandre, Claudio O; Damin, Daniel C

2009-01-01

AIM: To investigate the potential role of p53 codon 72 polymorphism as a risk factor for development of anal cancer. METHODS: Thirty-two patients with invasive anal carcinoma and 103 healthy blood donors were included in the study. p53 codon 72 polymorphism was analyzed in blood samples through polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. RESULTS: The relative frequency of each allele was 0.60 for Arg and 0.40 for Pro in patients with anal cancer, and 0.61 for Arg and 0.39 for Pro in normal controls. No significant differences in distribution of the codon 72 genotypes between patients and controls were found. CONCLUSION: These results do not support a role for the p53 codon 72 polymorphism in anal carcinogenesis. PMID:19777616

Ames and random amplified polymorphic DNA tests for the validation of the mutagenic and/or genotoxic potential of the drinking water disinfection by-products chloroform and bromoform.

PubMed

Khallef, Messaouda; Cenkci, Süleyman; Akyil, Dilek; Özkara, Arzu; Konuk, Muhsin; Benouareth, Djamel Eddine

2018-01-28

Chloroform and Bromoform are two abundant trihalomethanes found in Algerian drinking water. The investigation of the mutagenic hazard of these disinfection by-products was studied by Ames test as prokaryotic bioassay to show their mutagenic effects. For this, Salmonella typhimurium TA98 and TA100 strains were employed. Both chloroform and bromoform showed a direct mutagenic effect since the number of revertant colonies gradually increase in dose-dependent manner with all concentrations tested with the two bacterial strains and these were both in the absence and presence of S9 metabolic activation. The genotoxic hazard was also studied by random amplified polymorphic DNA test on the root cells of Allium cepa as eukaryotic bioassay. DNA extracted from the roots of the onion were incubated at different concentrations of chloroform and bromoform and then amplified by polymerase chain reaction. This was based on demonstrating a major effect of disappearance of bands compared to roots incubated in the negative control (distilled water). The results showed that these two compounds affected genomic DNA by breaks although by mutations.

Typing and Subtyping of 83 Clinical Isolates Purified from Surgically Implanted Silicone Feeding Tubes by Random Amplified Polymorphic DNA Amplification

PubMed Central

Dautle, Melanie P.; Ulrich, Ricky L.; Hughes, Thomas A.

2002-01-01

In this study, 83 clinical isolates purified from biofilms colonizing 18 silicone gastrostomy devices (12 “buttons” and six tubes converted to skin level devices) were selected for subtype characterization utilizing genetic analysis. The tubes, previously used for feeding, remained in place for 3 to 47 months (mean, 20.0 months) in children ranging in age from 6 months to 17 years. Classification of specific microbes using random amplified polymorphic DNA (RAPD) analysis revealed genetic similarities and differences among isolates belonging to the same genus. Both gram-positive and -negative bacteria were investigated, including 2 isolates of Bacillus brevis, 4 isolates of Bacillus licheniformis, 2 isolates of Bacillus pumilus, 3 isolates of Enterococcus durans, 19 isolates of Enterococcus faecalis, 8 isolates of Enterococcus faecium, 2 isolates of Enterococcus hirae, 7 isolates of Escherichia coli, 8 isolates of Lactobacillus plantarum, 19 isolates of Staphylococcus aureus, 2 isolates of Staphylococcus epidermidis, and 7 isolates of Staphylococcus saprophyticus. Amplified DNA fragments (amplicons) provided species-specific fingerprints for comparison by agarose gel electrophoresis. A total of 62 distinct RAPD types were categorized from the five genera studied. Typing analysis suggested cross acquisition of E. coli, E. faecalis, and S. aureus in three patient pairs. Genomic polymorphism detection proved efficient and reliable for classifying bacterial subtypes isolated from biofilms adhering to various portions of commonly employed enteral access tubes. PMID:11825951

Relationships among genetic makeup, active ingredient content, and place of origin of the medicinal plant Gastrodia tuber.

PubMed

Tao, Jun; Luo, Zhi-yong; Msangi, Chikira Ismail; Shu, Xiao-shun; Wen, Li; Liu, Shui-ping; Zhou, Chang-quan; Liu, Rui-xin; Hu, Wei-xin

2009-02-01

Gastrodia tuber and its component gastrodin have many pharmacological effects. The chemical fingerprints and gastrodin contents of eight Gastrodia populations were determined, and the genomic DNA polymorphism of the populations was investigated. Genetic distance coefficients among the populations were calculated using the DNA polymorphism data. A dendrogram of the genetic similarities between the populations was constructed using the genetic distance coefficients. The results indicated that the genomic DNA of Gastrodia tubers was highly polymorphic; the eight populations clustered into three major groups, and the gastrodin content varied greatly among these groups. There were obvious correlations among genetic makeup, gastrodin content, and place of origin. The ecological environments in Guizhou and Shanxi may be conducive to evolution and to gastrodin biosynthesis, and more suitable for cultivation of Gastrodia tubers. These findings may provide a scientific basis for overall genetic resource management and for the selection of locations for cultivating Gastrodia tubers.

C9orf72 nucleotide repeat structures initiate molecular cascades of disease.

PubMed

Haeusler, Aaron R; Donnelly, Christopher J; Periz, Goran; Simko, Eric A J; Shaw, Patrick G; Kim, Min-Sik; Maragakis, Nicholas J; Troncoso, Juan C; Pandey, Akhilesh; Sattler, Rita; Rothstein, Jeffrey D; Wang, Jiou

2014-03-13

A hexanucleotide repeat expansion (HRE), (GGGGCC)n, in C9orf72 is the most common genetic cause of the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here we identify a molecular mechanism by which structural polymorphism of the HRE leads to ALS/FTD pathology and defects. The HRE forms DNA and RNA G-quadruplexes with distinct structures and promotes RNA•DNA hybrids (R-loops). The structural polymorphism causes a repeat-length-dependent accumulation of transcripts aborted in the HRE region. These transcribed repeats bind to ribonucleoproteins in a conformation-dependent manner. Specifically, nucleolin, an essential nucleolar protein, preferentially binds the HRE G-quadruplex, and patient cells show evidence of nucleolar stress. Our results demonstrate that distinct C9orf72 HRE structural polymorphism at both DNA and RNA levels initiates molecular cascades leading to ALS/FTD pathologies, and provide the basis for a mechanistic model for repeat-associated neurodegenerative diseases.

Geographical distribution of genetic polymorphism of the pathogen Histoplasma capsulatum isolated from infected bats, captured in a central zone of Mexico.

PubMed

Taylor, Maria Lucia; Chávez-Tapia, Catalina B; Rojas-Martínez, Alberto; del Rocio Reyes-Montes, Maria; del Valle, Mirian Bobadilla; Zúñiga, Gerardo

2005-09-01

Fourteen Histoplasma capsulatum isolates recovered from infected bats captured in Mexican caves and two human H. capsulatum reference strains were analyzed using random amplification of polymorphic DNA PCR-based and partial DNA sequences of four genes. Cluster analysis of random amplification of polymorphic DNA-patterns revealed differences for two H. capsulatum isolates of one migratory bat Tadarida brasiliensis. Three groups were identified by distance and maximum-parsimony analyses of arf, H-anti, ole, and tub1 H. capsulatum genes. Group I included most isolates from infected bats and one clinical strain from central Mexico; group II included the two isolates from T. brasiliensis; the human G-217B reference strain from USA formed an independent group III. Isolates from group II showed diversity in relation to groups I and III, suggesting a different H. capsulatum population.

Association of REL Polymorphism with Cow's Milk Proteins Allergy in Pediatric Algerian Population.

PubMed

Rahmoun, Nesrine; El Mecherfi, Kamel Eddine; Bouchetara, Assia; Lardjem Hetraf, Sara; Dahmani Amira, Chahinez; Adda Neggaz, Leila; Boudjema, Abdallah; Zemani-Fodil, Faouzia; Kheroua, Omar

2018-02-01

Cow's milk proteins allergy (CMPA) pathogenesis involves complex immunological mechanisms with the participation of several cells and molecules involved in food allergy. The association of polymorphisms in the interleukin 4, Forkhead box P3 and the avian reticuloendotheliosis genes was investigated in an infant population with CMPA of Western Algeria. We obtained DNA and clinical data from milk allergic subjects during active phase and from a group of non-atopic control subjects. Our findings showed that the allele G of the cRel gene intronic polymorphism at +7883 positions was significantly higher among cow's milk proteins allergic patients compared to control subjects. The results of this study suggest a possible association of CMPA with cRel G+7883T polymorphism.

Identification of single-nucleotide polymorphisms of the prion protein gene in sika deer (Cervus nippon laiouanus)

PubMed Central

Jeong, Hyun-Jeong; Lee, Joong-Bok; Park, Seung-Yong; Song, Chang-Seon; Kim, Bo-Sook; Rho, Jung-Rae; Yoo, Mi-Hyun; Jeong, Byung-Hoon; Kim, Yong-Sun

2007-01-01

Polymorphisms of the prion protein gene (PRNP) have been detected in several cervid species. In order to confirm the genetic variations, this study examined the DNA sequences of the PRNP obtained from 33 captive sika deer (Cervus nippon laiouanus) in Korea. A total of three single-nucleotide polymorphisms (SNPs) at codons 100, 136 and 226 in the PRNP of the sika deer were identified. The polymorphic site located at codon 100 has not been reported. The SNPs detected at codons 100 and 226 induced amino acid substitutions. The SNP at codon 136 was a silent mutation that does not induce any amino acid change. The genotype and allele frequencies were determined for each of the SNPs. PMID:17679779

Tolerance of DNA Mismatches in Dmc1 Recombinase-mediated DNA Strand Exchange.

PubMed

Borgogno, María V; Monti, Mariela R; Zhao, Weixing; Sung, Patrick; Argaraña, Carlos E; Pezza, Roberto J

2016-03-04

Recombination between homologous chromosomes is required for the faithful meiotic segregation of chromosomes and leads to the generation of genetic diversity. The conserved meiosis-specific Dmc1 recombinase catalyzes homologous recombination triggered by DNA double strand breaks through the exchange of parental DNA sequences. Although providing an efficient rate of DNA strand exchange between polymorphic alleles, Dmc1 must also guard against recombination between divergent sequences. How DNA mismatches affect Dmc1-mediated DNA strand exchange is not understood. We have used fluorescence resonance energy transfer to study the mechanism of Dmc1-mediated strand exchange between DNA oligonucleotides with different degrees of heterology. The efficiency of strand exchange is highly sensitive to the location, type, and distribution of mismatches. Mismatches near the 3' end of the initiating DNA strand have a small effect, whereas most mismatches near the 5' end impede strand exchange dramatically. The Hop2-Mnd1 protein complex stimulates Dmc1-catalyzed strand exchange on homologous DNA or containing a single mismatch. We observed that Dmc1 can reject divergent DNA sequences while bypassing a few mismatches in the DNA sequence. Our findings have important implications in understanding meiotic recombination. First, Dmc1 acts as an initial barrier for heterologous recombination, with the mismatch repair system providing a second level of proofreading, to ensure that ectopic sequences are not recombined. Second, Dmc1 stepping over infrequent mismatches is likely critical for allowing recombination between the polymorphic sequences of homologous chromosomes, thus contributing to gene conversion and genetic diversity. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Tolerance of DNA Mismatches in Dmc1 Recombinase-mediated DNA Strand Exchange*

PubMed Central

Borgogno, María V.; Monti, Mariela R.; Zhao, Weixing; Sung, Patrick; Argaraña, Carlos E.; Pezza, Roberto J.

2016-01-01

Recombination between homologous chromosomes is required for the faithful meiotic segregation of chromosomes and leads to the generation of genetic diversity. The conserved meiosis-specific Dmc1 recombinase catalyzes homologous recombination triggered by DNA double strand breaks through the exchange of parental DNA sequences. Although providing an efficient rate of DNA strand exchange between polymorphic alleles, Dmc1 must also guard against recombination between divergent sequences. How DNA mismatches affect Dmc1-mediated DNA strand exchange is not understood. We have used fluorescence resonance energy transfer to study the mechanism of Dmc1-mediated strand exchange between DNA oligonucleotides with different degrees of heterology. The efficiency of strand exchange is highly sensitive to the location, type, and distribution of mismatches. Mismatches near the 3′ end of the initiating DNA strand have a small effect, whereas most mismatches near the 5′ end impede strand exchange dramatically. The Hop2-Mnd1 protein complex stimulates Dmc1-catalyzed strand exchange on homologous DNA or containing a single mismatch. We observed that Dmc1 can reject divergent DNA sequences while bypassing a few mismatches in the DNA sequence. Our findings have important implications in understanding meiotic recombination. First, Dmc1 acts as an initial barrier for heterologous recombination, with the mismatch repair system providing a second level of proofreading, to ensure that ectopic sequences are not recombined. Second, Dmc1 stepping over infrequent mismatches is likely critical for allowing recombination between the polymorphic sequences of homologous chromosomes, thus contributing to gene conversion and genetic diversity. PMID:26709229

Relative information content of polymorphic microsatellites and mitochondrial DNA for inferring dispersal and population genetic structure in the olive sea snake, Aipysurus laevis.

PubMed

Lukoschek, V; Waycott, M; Keogh, J S

2008-07-01

Polymorphic microsatellites are widely considered more powerful for resolving population structure than mitochondrial DNA (mtDNA) markers, particularly for recently diverged lineages or geographically proximate populations. Weaker population subdivision for biparentally inherited nuclear markers than maternally inherited mtDNA may signal male-biased dispersal but can also be attributed to marker-specific evolutionary characteristics and sampling properties. We discriminated between these competing explanations with a population genetic study on olive sea snakes, Aipysurus laevis. A previous mtDNA study revealed strong regional population structure for A. laevis around northern Australia, where Pleistocene sea-level fluctuations have influenced the genetic signatures of shallow-water marine species. Divergences among phylogroups dated to the Late Pleistocene, suggesting recent range expansions by previously isolated matrilines. Fine-scale population structure within regions was, however, poorly resolved for mtDNA. In order to improve estimates of fine-scale genetic divergence and to compare population structure between nuclear and mtDNA, 354 olive sea snakes (previously sequenced for mtDNA) were genotyped for five microsatellite loci. F statistics and Bayesian multilocus genotype clustering analyses found similar regional population structure as mtDNA and, after standardizing microsatellite F statistics for high heterozygosities, regional divergence estimates were quantitatively congruent between marker classes. Over small spatial scales, however, microsatellites recovered almost no genetic structure and standardized F statistics were orders of magnitude smaller than for mtDNA. Three tests for male-biased dispersal were not significant, suggesting that recent demographic expansions to the typically large population sizes of A. laevis have prevented microsatellites from reaching mutation-drift equilibrium and local populations may still be diverging.

Determining Phylogenetic Relationships Among Date Palm Cultivars Using Random Amplified Polymorphic DNA (RAPD) and Inter-Simple Sequence Repeat (ISSR) Markers.

PubMed

Haider, Nadia

2017-01-01

Investigation of genetic variation and phylogenetic relationships among date palm (Phoenix dactylifera L.) cultivars is useful for their conservation and genetic improvement. Various molecular markers such as restriction fragment length polymorphisms (RFLPs), simple sequence repeat (SSR), representational difference analysis (RDA), and amplified fragment length polymorphism (AFLP) have been developed to molecularly characterize date palm cultivars. PCR-based markers random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) are powerful tools to determine the relatedness of date palm cultivars that are difficult to distinguish morphologically. In this chapter, the principles, materials, and methods of RAPD and ISSR techniques are presented. Analysis of data generated from these two techniques and the use of these data to reveal phylogenetic relationships among date palm cultivars are also discussed.

Species-specific markers for the differential diagnosis of Trypanosoma cruzi and Trypanosoma rangeli and polymorphisms detection in Trypanosoma rangeli.

PubMed

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.

Analysis of mutational changes at the HLA locus in single human sperm.

PubMed

Huang, M M; Erlich, H A; Goodman, M F; Arnheim, N

1995-01-01

Using a simple and efficient single sperm PCR and direct sequencing method, we screened for HLA-DPB1 gene mutations that may give rise to new alleles at this highly polymorphic locus. More than 800 single sperm were studied from a heterozygous individual whose two alleles carried 16 nucleotide sequence differences clustered in six polymorphic regions. A potential microgene conversion event was detected. Unrepaired heteroduplex DNA similar to that which gives rise to postmeiotic segregation events in yeast was observed in three cases. Control experiments also revealed unusual sperm from DPB1 homozygous individuals. The data may help explain allelic diversity in the MHC and suggest that a possible source of human mosaicism may be incomplete DNA mismatch repair during gametogenesis.

A graphene-based platform for single nucleotide polymorphism (SNP) genotyping.

PubMed

Liu, Meng; Zhao, Huimin; Chen, Shuo; Yu, Hongtao; Zhang, Yaobin; Quan, Xie

2011-06-15

A facile, rapid, stable and sensitive approach for fluorescent detection of single nucleotide polymorphism (SNP) is designed based on DNA ligase reaction and π-stacking between the graphene and the nucleotide bases. In the presence of perfectly matched DNA, DNA ligase can catalyze the linkage of fluorescein amidite-labeled single-stranded DNA (ssDNA) and a phosphorylated ssDNA, and thus the formation of a stable duplex in high yield. However, the catalytic reaction cannot effectively carry out with one-base mismatched DNA target. In this case, we add graphene to the system in order to produce different quenching signals due to its different adsorption affinity for ssDNA and double-stranded DNA. Taking advantage of the unique surface property of graphene and the high discriminability of DNA ligase, the proposed protocol exhibits good performance in SNP genotyping. The results indicate that it is possible to accurately determine SNP with frequency as low as 2.6% within 40 min. Furthermore, the presented flexible strategy facilitates the development of other biosensing applications in the future. Copyright © 2011 Elsevier B.V. All rights reserved.

Genetic diversity study of Chromobacterium violaceum isolated from Kolli Hills by amplified ribosomal DNA restriction analysis (ARDRA) and random amplified polymorphic DNA (RAPD).

PubMed

Ponnusamy, K; Jose, S; Savarimuthu, I; Michael, G P; Redenbach, M

2011-09-01

Chromobacterium are saprophytes that cause highly fatal opportunistic infections. Identification and strain differentiation were performed to identify the strain variability among the environmental samples. We have evaluated the suitability of individual and combined methods to detect the strain variations of the samples collected in different seasons. Amplified ribosomal DNA restriction analysis (ARDRA) and random amplified polymorphic DNA (RAPD) profiles were obtained using four different restriction enzyme digestions (AluI, HaeIII, MspI and RsaI) and five random primers. A matrix of dice similarity coefficients was calculated and used to compare these restriction patterns. ARDRA showed rapid differentiation of strains based on 16S rDNA, but the combined RAPD and ARDRA gave a more reliable differentiation than when either of them was analysed individually. A high level of genetic diversity was observed, which indicates that the Kolli Hills' C. violaceum isolates would fall into at least three new clusters. Results showed a noteworthy bacterial variation and genetic diversity of C. violaceum in the unexplored, virgin forest area. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

High frequency of DD polymorphism of the angiotensin-converting enzyme gene in Turkish asthmatic patients.

PubMed

Urhan, Meral; Degirmenci, Irfan; Harmanci, Emel; Gunes, Hasan V; Metintas, Muzaffer; Basaran, Ayse

2004-01-01

The aim of this study is to detect the incidence of the angiotensin-converting enzyme (ACE) gene polymorphism in Turkish asthmatic patients and to examine whether there is an association between the disease and ACE gene polymorphism. In our study, the genomic DNA of 100 asthmatic patients and 88 healthy subjects was analyzed Genomic DNA was isolated from peripheral blood by using standard methods. The intron 16 of the ACE gene was amplified by the polymerase chain reaction (PCR) method using primers ACE and ACEX to examine the presence and absence of a 287-base pair (bp) DNA fragment that showed I/D polymorphism genotypes. PCR products were separated by agarose gel electrophoresis and were visualized by a charge-coupled device camera. Serum ACE activities were measured using an ACE kit. The results were evaluated statistically using the chi-square test and one-way analysis of variance. Although the population of patients with asthma was characterized by a higher frequency (30%) of the DD genotype of ACE, they were characterized by lower frequency (48%) of the ID genotype of ACE (DD, 16%, and ID, 64%, in healthy control subjects). The frequency of the I and D alleles of the ACE gene was not significantly different between asthmatic patients (0.46/0.54) and healthy controls (0.52/ 0.48). In addition, in both asthmatic patients and controls, there was a significant decrease of the levels of ACE activity in individuals that have II genotypes when compared with individuals that have DD genotypes. ACE activities were increased significantly in all asthmatic patients (67.20 +/- 1.95 IU/L) compared with all healthy controls (60.90 +/- 2.12 IU/L).

Genome-wide association study identifies phospholipase C zeta 1 (PLCz1) as a stallion fertility locus in Hanoverian warmblood horses.

PubMed

Schrimpf, Rahel; Dierks, Claudia; Martinsson, Gunilla; Sieme, Harald; Distl, Ottmar

2014-01-01

A consistently high level of stallion fertility plays an economically important role in modern horse breeding. We performed a genome-wide association study for estimated breeding values of the paternal component of the pregnancy rate per estrus cycle (EBV-PAT) in Hanoverian stallions. A total of 228 Hanoverian stallions were genotyped using the Equine SNP50 Beadchip. The most significant association was found on horse chromosome 6 for a single nucleotide polymorphism (SNP) within phospholipase C zeta 1 (PLCz1). In the close neighbourhood to PLCz1 is located CAPZA3 (capping protein (actin filament) muscle Z-line, alpha 3). The gene PLCz1 encodes a protein essential for spermatogenesis and oocyte activation through sperm induced Ca2+-oscillation during fertilization. We derived equine gene models for PLCz1 and CAPZA3 based on cDNA and genomic DNA sequences. The equine PLCz1 had four different transcripts of which two contained a premature termination codon. Sequencing all exons and their flanking sequences using genomic DNA samples from 19 Hanoverian stallions revealed 47 polymorphisms within PLCz1 and one SNP within CAPZA3. Validation of these 48 polymorphisms in 237 Hanoverian stallions identified three intronic SNPs within PLCz1 as significantly associated with EBV-PAT. Bioinformatic analysis suggested regulatory effects for these SNPs via transcription factor binding sites or microRNAs. In conclusion, non-coding polymorphisms within PLCz1 were identified as conferring stallion fertility and PLCz1 as candidate locus for male fertility in Hanoverian warmblood. CAPZA3 could be eliminated as candidate gene for fertility in Hanoverian stallions.

Genome-Wide Association Study Identifies Phospholipase C zeta 1 (PLCz1) as a Stallion Fertility Locus in Hanoverian Warmblood Horses

PubMed Central

Schrimpf, Rahel; Dierks, Claudia; Martinsson, Gunilla; Sieme, Harald; Distl, Ottmar

2014-01-01

A consistently high level of stallion fertility plays an economically important role in modern horse breeding. We performed a genome-wide association study for estimated breeding values of the paternal component of the pregnancy rate per estrus cycle (EBV-PAT) in Hanoverian stallions. A total of 228 Hanoverian stallions were genotyped using the Equine SNP50 Beadchip. The most significant association was found on horse chromosome 6 for a single nucleotide polymorphism (SNP) within phospholipase C zeta 1 (PLCz1). In the close neighbourhood to PLCz1 is located CAPZA3 (capping protein (actin filament) muscle Z-line, alpha 3). The gene PLCz1 encodes a protein essential for spermatogenesis and oocyte activation through sperm induced Ca2+-oscillation during fertilization. We derived equine gene models for PLCz1 and CAPZA3 based on cDNA and genomic DNA sequences. The equine PLCz1 had four different transcripts of which two contained a premature termination codon. Sequencing all exons and their flanking sequences using genomic DNA samples from 19 Hanoverian stallions revealed 47 polymorphisms within PLCz1 and one SNP within CAPZA3. Validation of these 48 polymorphisms in 237 Hanoverian stallions identified three intronic SNPs within PLCz1 as significantly associated with EBV-PAT. Bioinformatic analysis suggested regulatory effects for these SNPs via transcription factor binding sites or microRNAs. In conclusion, non-coding polymorphisms within PLCz1 were identified as conferring stallion fertility and PLCz1 as candidate locus for male fertility in Hanoverian warmblood. CAPZA3 could be eliminated as candidate gene for fertility in Hanoverian stallions. PMID:25354211

Functional characterization of polymorphisms in DNA repair genes using cytogenetic challenge assays.

PubMed

Au, William W; Salama, Salama A; Sierra-Torres, Carlos H

2003-11-01

A major barrier to understanding the role of polymorphic DNA repair genes for environmental cancer is that the functions of variant genotypes are largely unknown. Using our cytogenetic challenge assays, we conducted an investigation to address the deficiency. Using X-rays or ultraviolet (UV) light, we irradiated blood lymphocytes from 80 nonsmoking donors to challenge the cells to repair the induced DNA damage, and we analyzed expression of chromosome aberrations (CA) specific to the inducing agents. We have genotyped polymorphic DNA repair genes preferentially involved with base excision repair (BER) and nucleotide excision repair (NER) activities (XRCC1, XRCC3, APE1, XPD) corresponding to the repair of X-ray- and UV light-induced DNA damage, respectively. We expected that defects in specific DNA repair pathways due to polymorphisms would cause corresponding increases of specific CA. From our data, XRCC1 399Gln and XRCC3 241Met were associated with significant increases in chromosome deletions compared with the corresponding homozygous wild types (18.27 1.1 vs 14.79 1.2 and 18.22 0.99 vs 14.20 1.39, respectively); XPD 312Asn and XPD 751Gln were associated with significant increases in chromatid breaks compared with wild types (16.09 1.36 vs 11.41 0.98 and 16.87 1.27 vs 10.54 0.87, respectively), p < 0.05. The data indicate that XRCC1 399Gln and XRCC3 241Met are significantly defective in BER, and the XPD 312Asn and XPD 751Gln are significantly defective in NER. In addition, the variant genotypes interact significantly, with limited overlap of the two different repair pathways.

Single-strand conformation polymorphism (SSCP)-based mutation scanning approaches to fingerprint sequence variation in ribosomal DNA of ascaridoid nematodes.

PubMed

Zhu, X Q; Gasser, R B

1998-06-01

In this study, we assessed single-strand conformation polymorphism (SSCP)-based approaches for their capacity to fingerprint sequence variation in ribosomal DNA (rDNA) of ascaridoid nematodes of veterinary and/or human health significance. The second internal transcribed spacer region (ITS-2) of rDNA was utilised as the target region because it is known to provide species-specific markers for this group of parasites. ITS-2 was amplified by PCR from genomic DNA derived from individual parasites and subjected to analysis. Direct SSCP analysis of amplicons from seven taxa (Toxocara vitulorum, Toxocara cati, Toxocara canis, Toxascaris leonina, Baylisascaris procyonis, Ascaris suum and Parascaris equorum) showed that the single-strand (ss) ITS-2 patterns produced allowed their unequivocal identification to species. While no variation in SSCP patterns was detected in the ITS-2 within four species for which multiple samples were available, the method allowed the direct display of four distinct sequence types of ITS-2 among individual worms of T. cati. Comparison of SSCP/sequencing with the methods of dideoxy fingerprinting (ddF) and restriction endonuclease fingerprinting (REF) revealed that also ddF allowed the definition of the four sequence types, whereas REF displayed three of four. The findings indicate the usefulness of the SSCP-based approaches for the identification of ascaridoid nematodes to species, the direct display of sequence variation in rDNA and the detection of population variation. The ability to fingerprint microheterogeneity in ITS-2 rDNA using such approaches also has implications for studying fundamental aspects relating to mutational change in rDNA.

Buccal DNA collection: comparison of buccal swabs with FTA cards.

PubMed

Milne, Elizabeth; van Bockxmeer, Frank M; Robertson, Laila; Brisbane, Joanna M; Ashton, Lesley J; Scott, Rodney J; Armstrong, Bruce K

2006-04-01

Collection and analysis of DNA, most commonly from blood or buccal cells, is becoming more common in epidemiologic studies. Buccal samples, which are painless to take and relatively easily collected, are often the preferred source. There are several buccal cell collection methods: swabs, brushes, mouthwash, and treated cards, such as FTA or IsoCode cards. Few studies have systematically compared methods of buccal cell collection with respect to DNA yield and amplification success under similar conditions. We compared buccal DNA collection and amplification using buccal swabs and FTA cards in 122 control subjects from our Australian case-control study of childhood acute lymphoblastic leukaemia. Buccal DNA was quantified using a real-time PCR for beta-actin and genotyped at the loci of three polymorphisms (MTHFR 677C>T, ACE I/D, and XPD 1012G>A). PCR was successful with DNA from buccal swabs for 62% to 89% of subjects and from FTA cards for 83% to 100% of subjects, depending on the locus. The matched pair odds ratios (95% confidence interval) comparing success of FTA cards with buccal swabs are as follows: MTHFR 677C>T using PCR-RFLP, 12.5 (11.6-13.5) and using real-time PCR, 130.0 (113.1-152.8); ACE I/D using PCR-amplified fragment length polymorphism, 3.36 (3.2-3.5); XPD 1012G>A using real-time PCR, 150.0 (132.7-172.3). FTA cards are a robust DNA collection method and generally produce DNA suitable for PCR more reliably than buccal swabs. There are, however, technical challenges in handling discs punched from FTA cards that intending users should be aware of.

The evaluation of angiotensin-converting enzyme (ACE) gene I/D and IL-4 gene intron 3 VNTR polymorphisms in coronary artery disease.

PubMed

Basol, Nursah; Celik, Atac; Karakus, Nevin; Ozturk, Sibel Demir; Ozsoy, Sibel Demir; Yigit, Serbulent

2014-01-01

Genetic polymorphism is a strong risk factor for coronary artery disease (CAD). In the present study, our aim was to evaluate angiotensin-converting enzyme (ACE) gene I/D polymorphism and interleukin-4 (IL-4) gene Intron 3 variable number of tandem repeat (VNTR) polymorphism in CAD. One hundred and twenty-four CAD patients and one hundred and twenty-three controls were enrolled. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) analyses. The risk associated with inheriting the combined genotypes for the two polymorphisms were evaluated and it was found that the individuals who were P2P2-homozygous at IL-4 gene intron 3 VNTR and DD-homozygous at ACE gene I/D have a higher risk of developing CAD. Although, there is no correlation between IL4 VNTR polymorphism and ACE gene polymorphism and CAD, there is a strong association between CAD and co-existence of IL-4 VNTR and ACE gene polymorphisms in the Turkish population. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Ancestral chloroplast polymorphism and historical secondary contact in a broad hybrid zone of Aesculus (Sapindaceae).

PubMed

Modliszewski, Jennifer L; Thomas, David T; Fan, Chuanzhu; Crawford, Daniel J; Depamphilis, Claude W; Xiang, Qiu-Yun Jenny

2006-03-01

Knowledge regarding the origin and maintenance of hybrid zones is critical for understanding the evolutionary outcomes of natural hybridization. To evaluate the contribution of historical contact vs. long-distance gene flow in the formation of a broad hybrid zone in central and northern Georgia that involves Aesculus pavia, A. sylvatica, and A. flava, three cpDNA regions (matK, trnD-trnT, and trnH-trnK) were analyzed. The maternal inheritance of cpDNA in Aesculus was confirmed via sequencing of matK from progeny of controlled crosses. Restriction site analyses identified 21 unique haplotypes among 248 individuals representing 29 populations from parental species and hybrids. Haplotypes were sequenced for all cpDNA regions. Restriction site and sequence data were subjected to phylogeographic and population genetic analyses. Considerable cpDNA variation was detected in the hybrid zone, as well as ancestral cpDNA polymorphism; furthermore, the distribution of haplotypes indicates limited interpopulation gene flow via seeds. The genealogy and structure of genetic variation further support the historical presence of A. pavia in the Piedmont, although they are at present locally extinct. In conjunction with previous allozyme studies, the cpDNA data suggest that the hybrid zone originated through historical local gene flow, yet is maintained by periodic long-distance pollen dispersal.

Methylation-sensitive amplified polymorphism analysis of Verticillium wilt-stressed cotton (Gossypium).

PubMed

Wang, W; Zhang, M; Chen, H D; Cai, X X; Xu, M L; Lei, K Y; Niu, J H; Deng, L; Liu, J; Ge, Z J; Yu, S X; Wang, B H

2016-10-06

In this study, a methylation-sensitive amplification polymorphism analysis system was used to analyze DNA methylation level in three cotton accessions. Two disease-sensitive near-isogenic lines, PD94042 and IL41, and one disease-resistant Gossypium mustelinum accession were exposed to Verticillium wilt, to investigate molecular disease resistance mechanisms in cotton. We observed multiple different DNA methylation types across the three accessions following Verticillium wilt exposure. These included hypomethylation, hypermethylation, and other patterns. In general, the global DNA methylation level was significantly increased in the disease-resistant accession G. mustelinum following disease exposure. In contrast, there was no significant difference in the disease-sensitive accession PD94042, and a significant decrease was observed in IL41. Our results suggest that disease-resistant cotton might employ a mechanism to increase methylation level in response to disease stress. The differing methylation patterns, together with the increase in global DNA methylation level, might play important roles in tolerance to Verticillium wilt in cotton. Through cloning and analysis of differently methylated DNA sequences, we were also able to identify several genes that may contribute to disease resistance in cotton. Our results revealed the effect of DNA methylation on cotton disease resistance, and also identified genes that played important roles, which may shed light on the future cotton disease-resistant molecular breeding.

Neutral and Non-Neutral Evolution of Duplicated Genes with Gene Conversion

PubMed Central

Fawcett, Jeffrey A.; Innan, Hideki

2011-01-01

Gene conversion is one of the major mutational mechanisms involved in the DNA sequence evolution of duplicated genes. It contributes to create unique patters of DNA polymorphism within species and divergence between species. A typical pattern is so-called concerted evolution, in which the divergence between duplicates is maintained low for a long time because of frequent exchanges of DNA fragments. In addition, gene conversion affects the DNA evolution of duplicates in various ways especially when selection operates. Here, we review theoretical models to understand the evolution of duplicates in both neutral and non-neutral cases. We also explain how these theories contribute to interpreting real polymorphism and divergence data by using some intriguing examples. PMID:24710144

Variation in Ribosomal DNA among Isolates of the Mycorrhizal Fungus Cenococcum Geophilum FR.

NASA Astrophysics Data System (ADS)

Lobuglio, Katherine Frances

1990-01-01

Cenococcum geophilum Fr., a cosmopolitan mycorrhizal fungus, is well-known for its extremely wide host and habitat range. The ecological diversity of C. geophilum sharply contrasts its present taxonomic status as a monotypic form -genus. Restriction fragment length polymorphisms (RFLPs) in nuclear ribosomal DNA (rDNA) was used to assess the degree of genetic variation among 72 isolates of C. geophilum. The probe used in this study was the rDNA repeat cloned from C. geophilum isolate A145 (pCG15). Length of the rDNA repeat was approximately 9 kb. The rDNA clone was mapped for 5 restriction endonucleases. Hybridization with cloned Saccharomyces cerevisiae rDNA (pSR118, and pSR125 containing the 18S, and 5.8-25S rRNA genes respectively), and alignment of restriction endonuclease sites conserved in the rDNA genes of other fungi, were used to position the corresponding rDNAs of C. geophilum. Southern hybridizations with EcoRI, HindIII, XhoI, and PstI digested DNAs indicated extensive variation among the C. geophilum isolates, greater than has been previously reported to occur within a fungal species. Most of the rDNA polymorphisms occurred in the IGS region. Restriction endonuclease site and length polymorphisms were also observed in the 5.8S-26S genic regions. Sixteen size categories of length mutations, 6 restriction endonuclease site additions, and 4 restriction endonuclease site deletions were determined using isolate A145 as a reference. The rDNA repeat length among the isolates varied from approximately 8.5 to 10.2 kb. RFLPs were also observed in the mitochondrial (mt) 24S rRNA gene and flanking regions of HindIII digested DNAs of C. geophilum isolates representing both geographically distinct and similar origins. Among the C. geophilum isolates analyzed there were fewer RFLPs in mt-DNA than in nuclear rDNA. EcoRI rDNA phenotypes between C. geophilum and Elaphomyces anthracinus, its proposed teleomorph or sexual state, did not correspond. In addition, the four Elaphomyces species examined had smaller rDNA repeat sizes (approximately 7.3 to 8.0 kb) than that observed among C. geophilum isolates. UPGMA cluster analysis grouped C. geophilum isolates, on the basis of shared nuclear rDNA phenotypes, into a broad range of clusters ranging from 100% to 44% similarity. Limited correlation was observed among nuclear rDNA phenotypes and culture morphology, mycorrhizal characteristics, or geographic origins of the isolates. The amount of genetic variation demonstrated in this study indicates that C. geophilum is either an extremely heterogenous species or it represents more than one species and possibly more than one genus.

Characterization and compilation of polymorphic simple sequence repeat (SSR) markers of peanut from public database

PubMed Central

2012-01-01

Background There are several reports describing thousands of SSR markers in the peanut (Arachis hypogaea L.) genome. There is a need to integrate various research reports of peanut DNA polymorphism into a single platform. Further, because of lack of uniformity in the labeling of these markers across the publications, there is some confusion on the identities of many markers. We describe below an effort to develop a central comprehensive database of polymorphic SSR markers in peanut. Findings We compiled 1,343 SSR markers as detecting polymorphism (14.5%) within a total of 9,274 markers. Amongst all polymorphic SSRs examined, we found that AG motif (36.5%) was the most abundant followed by AAG (12.1%), AAT (10.9%), and AT (10.3%).The mean length of SSR repeats in dinucleotide SSRs was significantly longer than that in trinucleotide SSRs. Dinucleotide SSRs showed higher polymorphism frequency for genomic SSRs when compared to trinucleotide SSRs, while for EST-SSRs, the frequency of polymorphic SSRs was higher in trinucleotide SSRs than in dinucleotide SSRs. The correlation of the length of SSR and the frequency of polymorphism revealed that the frequency of polymorphism was decreased as motif repeat number increased. Conclusions The assembled polymorphic SSRs would enhance the density of the existing genetic maps of peanut, which could also be a useful source of DNA markers suitable for high-throughput QTL mapping and marker-assisted selection in peanut improvement and thus would be of value to breeders. PMID:22818284

Effects of different preservation methods on inter simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) molecular markers in botanic samples.

PubMed

Wang, Xiaolong; Li, Lin; Zhao, Jiaxin; Li, Fangliang; Guo, Wei; Chen, Xia

2017-04-01

To evaluate the effects of different preservation methods (stored in a -20°C ice chest, preserved in liquid nitrogen and dried in silica gel) on inter simple sequence repeat (ISSR) or random amplified polymorphic DNA (RAPD) analyses in various botanical specimens (including broad-leaved plants, needle-leaved plants and succulent plants) for different times (three weeks and three years), we used a statistical analysis based on the number of bands, genetic index and cluster analysis. The results demonstrate that methods used to preserve samples can provide sufficient amounts of genomic DNA for ISSR and RAPD analyses; however, the effect of different preservation methods on these analyses vary significantly, and the preservation time has little effect on these analyses. Our results provide a reference for researchers to select the most suitable preservation method depending on their study subject for the analysis of molecular markers based on genomic DNA. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Noninvasive individual and species identification of jaguars (Panthera onca), pumas (Puma concolor) and ocelots (Leopardus pardalis) in Belize, Central America using cross-species microsatellites and faecal DNA.

PubMed

Wultsch, Claudia; Waits, Lisette P; Kelly, Marcella J

2014-11-01

There is a great need to develop efficient, noninvasive genetic sampling methods to study wild populations of multiple, co-occurring, threatened felids. This is especially important for molecular scatology studies occurring in challenging tropical environments where DNA degrades quickly and the quality of faecal samples varies greatly. We optimized 14 polymorphic microsatellite loci for jaguars (Panthera onca), pumas (Puma concolor) and ocelots (Leopardus pardalis) and assessed their utility for cross-species amplification. Additionally, we tested their reliability for species and individual identification using DNA from faeces of wild felids detected by a scat detector dog across Belize in Central America. All microsatellite loci were successfully amplified in the three target species, were polymorphic with average expected heterozygosities of HE = 0.60 ± 0.18 (SD) for jaguars, HE = 0.65 ± 0.21 (SD) for pumas and HE = 0.70 ± 0.13 (SD) for ocelots and had an overall PCR amplification success of 61%. We used this nuclear DNA primer set to successfully identify species and individuals from 49% of 1053 field-collected scat samples. This set of optimized microsatellite multiplexes represents a powerful tool for future efforts to conduct noninvasive studies on multiple, wild Neotropical felids. © 2014 John Wiley & Sons Ltd.

Are SNP-Smoking Association Studies Needed in Controls? DNA Repair Gene Polymorphisms and Smoking Intensity

PubMed Central

Verde, Zoraida; Reinoso, Luis; Chicharro, Luis Miguel; Resano, Pilar; Sánchez-Hernández, Ignacio; Rodríguez González-Moro, Jose Miguel; Bandrés, Fernando

2015-01-01

Variations in tobacco-related cancers, incidence and prevalence reflect differences in tobacco consumption in addition to genetic factors. Besides, genes related to lung cancer risk could be related to smoking behavior. Polymorphisms altering DNA repair capacity may lead to synergistic effects with tobacco carcinogen-induced lung cancer risk. Common problems in genetic association studies, such as presence of gene-by-environment (G x E) correlation in the population, may reduce the validity of these designs. The main purpose of this study was to evaluate the independence assumption for selected SNPs and smoking behaviour in a cohort of 320 healthy Spanish smokers. We found an association between the wild type alleles of XRCC3 Thr241Met or KLC3 Lys751Gln and greater smoking intensity (OR = 12.98, 95% CI = 2.86–58.82 and OR=16.90, 95% CI=2.09-142.8; respectively). Although preliminary, the results of our study provide evidence that genetic variations in DNA-repair genes may influence both smoking habits and the development of lung cancer. Population-specific G x E studies should be carried out when genetic and environmental factors interact to cause the disease. PMID:26017978

Systematic study of association of four GABAergic genes: glutamic acid decarboxylase 1 gene, glutamic acid decarboxylase 2 gene, GABA(B) receptor 1 gene and GABA(A) receptor subunit beta2 gene, with schizophrenia using a universal DNA microarray.

PubMed

Zhao, Xu; Qin, Shengying; Shi, Yongyong; Zhang, Aiping; Zhang, Jing; Bian, Li; Wan, Chunling; Feng, Guoyin; Gu, Niufan; Zhang, Guangqi; He, Guang; He, Lin

2007-07-01

Several studies have suggested the dysfunction of the GABAergic system as a risk factor in the pathogenesis of schizophrenia. In the present study, case-control association analysis was conducted in four GABAergic genes: two glutamic acid decarboxylase genes (GAD1 and GAD2), a GABA(A) receptor subunit beta2 gene (GABRB2) and a GABA(B) receptor 1 gene (GABBR1). Using a universal DNA microarray procedure we genotyped a total of 20 SNPs on the above four genes in a study involving 292 patients and 286 controls of Chinese descent. Statistically significant differences were observed in the allelic frequencies of the rs187269C/T polymorphism in the GABRB2 gene (P=0.0450, chi(2)=12.40, OR=1.65) and the -292A/C polymorphism in the GAD1 gene (P=0.0450, chi(2)=14.64 OR=1.77). In addition, using an electrophoretic mobility shift assay (EMSA), we discovered differences in the U251 nuclear protein binding to oligonucleotides representing the -292 SNP on the GAD1 gene, which suggests that the -292C allele has reduced transcription factor binding efficiency compared with the 292A allele. Using the multifactor-dimensionality reduction method (MDR), we found that the interactions among the rs187269C/T polymorphism in the GABRB2 gene, the -243A/G polymorphism in the GAD2 gene and the 27379C/T and 661C/T polymorphisms in the GAD1 gene revealed a significant association with schizophrenia (P<0.001). These findings suggest that the GABRB2 and GAD1 genes alone and the combined effects of the polymorphisms in the four GABAergic system genes may confer susceptibility to the development of schizophrenia in the Chinese population.

Nuclear DNA analyses in genetic studies of populations: practice, problems and prospects.

PubMed

Zhang, De-Xing; Hewitt, Godfrey M

2003-03-01

Population-genetic studies have been remarkably productive and successful in the last decade following the invention of PCR technology and the introduction of mitochondrial and microsatellite DNA markers. While mitochondrial DNA has proven powerful for genealogical and evolutionary studies of animal populations, and microsatellite sequences are the most revealing DNA markers available so far for inferring population structure and dynamics, they both have important and unavoidable limitations. To obtain a fuller picture of the history and evolutionary potential of populations, genealogical data from nuclear loci are essential, and the inclusion of other nuclear markers, i.e. single copy nuclear polymorphic (scnp) sequences, is clearly needed. Four major uncertainties for nuclear DNA analyses of populations have been facing us, i.e. the availability of scnp markers for carrying out such analysis, technical laboratory hurdles for resolving haplotypes, difficulty in data analysis because of recombination, low divergence levels and intraspecific multifurcation evolution, and the utility of scnp markers for addressing population-genetic questions. In this review, we discuss the availability of highly polymorphic single copy DNA in the nuclear genome, describe patterns and rate of evolution of nuclear sequences, summarize past empirical and theoretical efforts to recover and analyse data from scnp markers, and examine the difficulties, challenges and opportunities faced in such studies. We show that although challenges still exist, the above-mentioned obstacles are now being removed. Recent advances in technology and increases in statistical power provide the prospect of nuclear DNA analyses becoming routine practice, allowing allele-discriminating characterization of scnp loci and microsatellite loci. This certainly will increase our ability to address more complex questions, and thereby the sophistication of genetic analyses of populations.

A novel, non-functional, COL1A1 polymorphism is not associated with lumbar disk disease in young male Greek subjects unlike that of the Sp1 site

PubMed Central

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

Development of EST Intron-Targeting SNP Markers for Panax ginseng and Their Application to Cultivar Authentication.

PubMed

Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun

2016-06-04

Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to "Gopoong" and "K-1" were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information.

Structural polymorphism exhibited by a quasipalindrome present in the locus control region (LCR) of the human beta-globin gene cluster.

PubMed

Kaushik, Mahima; Kukreti, Shrikant

2006-01-01

Structural polymorphism of DNA is a widely accepted property. A simple addition to this perception has been our recent finding, where a single nucleotide polymorphism (SNP) site present in a quasipalindromic sequence of beta-globin LCR exhibited a hairpin-duplex equilibrium. Our current studies explore that secondary structures adopted by individual complementary strands compete with formation of a perfect duplex. Using gel-electrophoresis, ultraviolet (UV)-thermal denaturation, circular dichroism (CD) techniques, we have demonstrated the structural transitions within a perfect duplex containing 11 bp quasipalindromic stretch (TGGGG(G/C)CCCCA), to hairpins and bulge duplex forms. The extended version of the 11 bp duplex, flanked by 5 bp on both sides also demonstrated conformational equilibrium between duplex and hairpin species. Gel-electrophoresis confirms that the duplex coexists with hairpin and bulge duplex/cruciform species. Further, in CD spectra of duplexes, presence of two overlapping positive peaks at 265 and 285 nm suggest the features of A- as well as B-type DNA conformation and show oligomer concentration dependence, manifested in A --> B transition. This indicates the possibility of an architectural switching at quasipalindromic region between linear duplex to a cruciform structure. Such DNA structural variations are likely to be found in the mechanics of molecular recognition and manipulation by proteins.

Different DNA methylation patterns detected by the Amplified Methylation Polymorphism Polymerase Chain Reaction (AMP PCR) technique among various cell types of bulls.

PubMed

Phutikanit, Nawapen; Suwimonteerabutr, Junpen; Harrison, Dion; D'Occhio, Michael; Carroll, Bernie; Techakumphu, Mongkol

2010-03-05

The purpose of this study was to apply an arbitrarily primed methylation sensitive polymerase chain reaction (PCR) assay called Amplified Methylation Polymorphism Polymerase Chain Reaction (AMP PCR) to investigate the methylation profiles of somatic and germ cells obtained from Holstein bulls. Genomic DNA was extracted from sperm, leukocytes and fibroblasts obtained from three bulls and digested with a methylation sensitive endonuclease (HpaII). The native genomic and enzyme treated DNA samples were used as templates in an arbitrarily primed-PCR assay with 30 sets of single short oligonucleotide primer. The PCR products were separated on silver stained denaturing polyacrylamide gels. Three types of PCR markers; digestion resistant-, digestion sensitive-, and digestion dependent markers, were analyzed based on the presence/absence polymorphism of the markers between the two templates. Approximately 1,000 PCR markers per sample were produced from 27 sets of primer and most of them (>90%) were digestion resistant markers. The highest percentage of digestion resistant markers was found in leukocytic DNA (94.8%) and the lowest in fibroblastic DNA (92.3%, P < or = 0.05). Spermatozoa contained a higher number of digestion sensitive markers when compared with the others (3.6% vs. 2.2% and 2.6% in leukocytes and fibroblasts respectively, P < or = 0.05). The powerfulness of the AMP PCR assay was the generation of methylation-associated markers without any prior knowledge of the genomic sequence. The data obtained from different primers provided an overview of genome wide DNA methylation content in different cell types. By using this technique, we found that DNA methylation profile is tissue-specific. Male germ cells were hypomethylated at the HpaII locations when compared with somatic cells, while the chromatin of the well-characterized somatic cells was heavily methylated when compared with that of the versatile somatic cells.

Functional analysis of regulatory single-nucleotide polymorphisms.

PubMed

Pampín, Sandra; Rodríguez-Rey, José C

2007-04-01

The identification of regulatory polymorphisms has become a key problem in human genetics. In the past few years there has been a conceptual change in the way in which regulatory single-nucleotide polymorphisms are studied. We revise the new approaches and discuss how gene expression studies can contribute to a better knowledge of the genetics of common diseases. New techniques for the association of single-nucleotide polymorphisms with changes in gene expression have been recently developed. This, together with a more comprehensive use of the old in-vitro methods, has produced a great amount of genetic information. When added to current databases, it will help to design better tools for the detection of regulatory single-nucleotide polymorphisms. The identification of functional regulatory single-nucleotide polymorphisms cannot be done by the simple inspection of DNA sequence. In-vivo techniques, based on primer-extension, and the more recently developed 'haploChIP' allow the association of gene variants to changes in gene expression. Gene expression analysis by conventional in-vitro techniques is the only way to identify the functional consequences of regulatory single-nucleotide polymorphisms. The amount of information produced in the last few years will help to refine the tools for the future analysis of regulatory gene variants.

Multiplex fluorescent PCR for noninvasive prenatal detection of fetal-derived paternally inherited diseases using circulatory fetal DNA in maternal plasma.

PubMed

Tang, Dong-ling; Li, Yan; Zhou, Xin; Li, Xia; Zheng, Fang

2009-05-01

To develop a fluorescent polymerase chain reaction (PCR) assay for the detection of circulating fetal DNA in maternal plasma and use the established multiplex in noninvasive prenatal genetic diagnosis and its further applications in forensic casework. The DNA template was extracted from 47 pregnant women and the whole blood samples from the stated biological fathers were used to detect genotype. Using multiplex fluorescent PCR at 16 different polymorphic short tandem repeat (STR) loci, maternal DNA extracted from plasma samples at early pregnancy, medium pregnancy and late pregnancy were used to detect genotype. Their husbands' DNA was also used for fetal genotype ascertainment. Multiplex fluorescent PCR with 16 polymorphic short tandem repeats revealed the presence of fetal DNA in all cases. Every pregnant women/husband pair was informative in at least 3 of 16 loci. The chances of detecting paternally inherited fetal alleles ranged from 66.67 to 94.12%. They are 66.67% in early pregnancy, 85.71% in medium pregnancy and 94.12% in late pregnancy. The accuracy of Multiplex PCR assay to detect fetal DNA was 100%. Circulating fetal DNA analysis can be used as a possible alternative tool in routine laboratory prenatal diagnosis in the near future; this highly polymorphic STR multiplex has greatly improved the chances of detecting paternally inherited fetal alleles compared with other fetal DNA detection systems that use fetus-derived Y sequences to detect only male fetal DNA in maternal plasma. Our proposed technique can be applied to both female and male fetuses, which provides a sensitive, accurate and efficient method for noninvasive prenatal genetic diagnosis and forensic casework.

Discrimination of closely related species in tintinnid ciliates: new insights on crypticity and polymorphism in the genus Helicostomella.

PubMed

Santoferrara, Luciana F; Tian, Michael; Alder, Viviana A; McManus, George B

2015-02-01

This study focuses on the utility of molecular markers for the discrimination of closely related species in tintinnid ciliates. We analyzed the ecologically important genus Helicostomella by sequencing part of the large-subunit rDNA (LSU rDNA) and the 5.8S rDNA combined with the internally transcribed spacer regions 1 and 2 (5.8S rDNA-ITS) from forty-five individuals collected in NW and SW Atlantic waters and after culturing. Although all described Helicostomella species represent a continuum of morphologies, forms with shorter or longer loricae would correspond to different species according to previous molecular data. Here we observed that long forms show both crypticity (i.e. two almost identical long forms with different DNA sequences) and polymorphism (i.e. some long forms develop significantly shorter loricae after culturing). Reviewing all available tintinnid sequences, we found that 1) three Helicostomella clusters are consistent with different species from a molecular perspective, although these clusters are neither clearly differentiated by their loricae nor unambiguously linked to described species, 2) Helicostomella is closely related (probably to the family or genus level) to four "Tintinnopsis-like" morphospecies, and 3) if considered separately, neither LSU rDNA nor 5.8S rDNA-ITS completely discriminate closely related species, thus supporting the use of multi-gene barcodes for tintinnids. Copyright © 2014 Elsevier GmbH. All rights reserved.

Structural polymorphism at LCR and its role in beta-globin gene regulation.

PubMed

Kukreti, Shrikant; Kaur, Harpreet; Kaushik, Mahima; Bansal, Aparna; Saxena, Sarika; Kaushik, Shikha; Kukreti, Ritushree

2010-09-01

Information on the secondary structures and conformational manifestations of eukaryotic DNA and their biological significance with reference to gene regulation and expression is limited. The human beta-globin gene Locus Control Region (LCR), a dominant regulator of globin gene expression, is a contiguous piece of DNA with five tissue-specific DNase I-hypersensitive sites (HSs). Since these HSs have a high density of transcription factor binding sites, structural interdependencies between HSs and different promoters may directly or indirectly regulate LCR functions. Mutations and SNPs may stabilize or destabilize the local secondary structures, affecting the gene expression by changes in the protein-DNA recognition patterns. Various palindromic or quasi-palindromic segments within LCR, could cause structural polymorphism and geometrical switching of DNA. This emphasizes the importance of understanding of the sequence-dependent variations of the DNA structure. Such structural motifs might act as regulatory elements. The local conformational variability of a DNA segment or action of a DNA specific protein is key to create and maintain active chromatin domains and affect transcription of various tissue specific beta-globin genes. We, summarize here the current status of beta-globin LCR structure and function. Further structural studies at molecular level and functional genomics might solve the regulatory puzzles that control the beta-globin gene locus. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

A Meta-Analysis of the Association between DNMT1 Polymorphisms and Cancer Risk.

PubMed

Li, Hao; Liu, Jing-Wei; Sun, Li-Ping; Yuan, Yuan

2017-01-01

Previous studies have examined the associations of DNA methyltransferase 1 ( DNMT1 ) polymorphisms, including single nucleotide polymorphisms rs16999593 (T/C), rs2228611 (G/A), and rs2228612 (A/G), with cancer risk. However, the results are inconclusive. The aim of this meta-analysis is to elucidate the associations between DNMT1 polymorphisms and cancer susceptibility. The PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure databases were searched systematically to identify potentially eligible reports. Odd ratios and 95% confidence intervals were used to evaluate the strength of association between three DNMT1 polymorphisms and cancer risk. A total of 16 studies were finally included in the meta-analysis, namely, nine studies of 3378 cases and 4244 controls for rs16999593, 11 studies of 3643 cases and 3866 controls for rs2228611, and three studies of 1343 cases and 1309 controls for rs2228612. The DNMT1 rs2228612 (A/G) polymorphism was significantly related to cancer risk in the recessive model. The meta-analysis also suggested that DNMT1 rs16999593 (T/C) may be associated with gastric cancer, while rs2228611 (G/A) may be associated with breast cancer. In future research, large-scale and well-designed studies are required to verify these findings.

Cytogenetic and molecular aspects of absolute teratozoospermia: comparison between polymorphic and monomorphic forms.

PubMed

Brahem, Sonia; Elghezal, Hatem; Ghédir, Houda; Landolsi, Hanène; Amara, Abdelbacett; Ibala, Samira; Gribaa, Moez; Saad, Ali; Mehdi, Meriem

2011-12-01

To compare the results of cytogenetic and molecular analysis between absolute polymorphic and monomorphic teratozoospermia. The semen samples from patients with polymorphic teratozoospermia (n = 20), globozoospermia (n = 8), or macrocephalic sperm head syndrome (n = 12), and healthy fertile men (n = 20) were analyzed according to the World Health Organization criteria. The constitutional blood karyotype of the patients was performed on cultured lymphocytes, according to standard techniques. Microdeletion analysis of the Y chromosomes used a sequence tagged site-polymerase chain reaction technique. Triple-color fluorescent in situ hybridization for chromosomes X, Y, and 18 were used to analyze the meiotic segregation. DNA fragmentation was detected using the terminal desoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick-end labeling assay. Whatever the type of teratozoospermia, a normal karyotype and an absence of Y chromosome microdeletion were shown for all patients. A significant increase in the sperm aneuploidy rate and DNA fragmentation were shown, regardless of the type of teratozoospermia. Spermatozoa of the patients with globozoospermia carry an abnormal chromosomal constitution and DNA damage rate with the same frequency as that found in the sperm of patients with absolute polymorphic teratozoospermia. However, a greater sperm aneuploidy rate and DNA fragmentation were found in patients whose teratozoospermia was mainly characterized by increased rates of spermatozoa with macrocephalic head and multiple flagella. Our data have demonstrated that DNA fragmentation and sperm aneuploidy are critical tests in teratozoospermic men, because the results could negatively affect the intracytoplasmic sperm injection outcomes and might play an important role in the counseling of couples considering intracytoplasmic sperm injection. Copyright © 2011 Elsevier Inc. All rights reserved.

Sequence-related amplified polymorphism (SRAP) markers: A potential resource for studies in plant molecular biology(1.).

PubMed

Robarts, Daniel W H; Wolfe, Andrea D

2014-07-01

In the past few decades, many investigations in the field of plant biology have employed selectively neutral, multilocus, dominant markers such as inter-simple sequence repeat (ISSR), random-amplified polymorphic DNA (RAPD), and amplified fragment length polymorphism (AFLP) to address hypotheses at lower taxonomic levels. More recently, sequence-related amplified polymorphism (SRAP) markers have been developed, which are used to amplify coding regions of DNA with primers targeting open reading frames. These markers have proven to be robust and highly variable, on par with AFLP, and are attained through a significantly less technically demanding process. SRAP markers have been used primarily for agronomic and horticultural purposes, developing quantitative trait loci in advanced hybrids and assessing genetic diversity of large germplasm collections. Here, we suggest that SRAP markers should be employed for research addressing hypotheses in plant systematics, biogeography, conservation, ecology, and beyond. We provide an overview of the SRAP literature to date, review descriptive statistics of SRAP markers in a subset of 171 publications, and present relevant case studies to demonstrate the applicability of SRAP markers to the diverse field of plant biology. Results of these selected works indicate that SRAP markers have the potential to enhance the current suite of molecular tools in a diversity of fields by providing an easy-to-use, highly variable marker with inherent biological significance.

Sequence-related amplified polymorphism (SRAP) markers: A potential resource for studies in plant molecular biology1

PubMed Central

Robarts, Daniel W. H.; Wolfe, Andrea D.

2014-01-01

In the past few decades, many investigations in the field of plant biology have employed selectively neutral, multilocus, dominant markers such as inter-simple sequence repeat (ISSR), random-amplified polymorphic DNA (RAPD), and amplified fragment length polymorphism (AFLP) to address hypotheses at lower taxonomic levels. More recently, sequence-related amplified polymorphism (SRAP) markers have been developed, which are used to amplify coding regions of DNA with primers targeting open reading frames. These markers have proven to be robust and highly variable, on par with AFLP, and are attained through a significantly less technically demanding process. SRAP markers have been used primarily for agronomic and horticultural purposes, developing quantitative trait loci in advanced hybrids and assessing genetic diversity of large germplasm collections. Here, we suggest that SRAP markers should be employed for research addressing hypotheses in plant systematics, biogeography, conservation, ecology, and beyond. We provide an overview of the SRAP literature to date, review descriptive statistics of SRAP markers in a subset of 171 publications, and present relevant case studies to demonstrate the applicability of SRAP markers to the diverse field of plant biology. Results of these selected works indicate that SRAP markers have the potential to enhance the current suite of molecular tools in a diversity of fields by providing an easy-to-use, highly variable marker with inherent biological significance. PMID:25202637

[Individual susceptibility to occupational carcinogens: the evidence from biomonitoring and molecular epidemiology studies].

PubMed

Pavanello, S; Clonfero, E

2004-01-01

This paper reviews the literature on the influence of metabolic and DNA repair polymorphisms of biological indicators of genotoxic risk commonly used in biomonitoring occupational exposure to carcinogens. Genetic polymorphisms which influence biomarkers (urinary metabolites, protein and DNA adducts), include P450 cytochromes (CYPs) and glutathione S-transferases (GSTs) in exposure to polycyclic aromatic hydrocarbons (PAHs), and acetyltransferases (NATs) in exposure to aromatic amines (AAs). As regards exposure to benzene, also relevant is the influence of epoxydohydrolase (EPHX) and NAD(P)H quinone oxidoreductase (NQO1) on the urinary excretion of t,t-muconic and phenylmercapturic acids. With respect to occupational exposure to styrene, EPHX significantly influences the levels of Chromosome Aberrations (CAs), strongly predictive genotoxic biomarkers of cancer risk. Some recent studies examine the role of polymorphisms linked to DNA repair genes in the modulation of genotoxic risk associated with PAH exposure, both for life-style (dietary and smoking behaviour) and for occupational reasons. In addition, molecular epidemiology studies (case/control studies) of lung cancer in smokers published since 2000 may also be viewed as representing models of effects due to exposure to carcinogenic mixtures, some of which are present in the working environment (e.g., BaP, benzene, AAs). Almost all studies show the clearcut influence (i.e., increased lung cancer risk with OR > or = 2) of genetic polymorphisms linked to PAH metabolism (in particular, CYPIA1, GSTM1 and P1). Among the risk factors are the different mutagen sensitivity towards, for instance, bleomycin and BaP (tested in vitro), the reduced repair capacity to DNA damage induced by BaP, and increases in some biomarkers of early biological effect (DNA adducts and stable CAs). Other risk factors, such as heredity (siblings of cancer patients have a risk factor > or = 3 with respect to the general population), ethnicity (Chileans > Caucasians; Japanese > Americans) and gender (women > men), have still not been clearly characterized and these are also reported in this paper. It is clear from the above that genetic differences underlie individual susceptibility to lung cancer, whether caused by exposure to tobacco smoke or to occupational carcinogens like PAHs. Some of these indicators of exposure/individual susceptibility can be evaluated in groups at high risk of occupational lung cancer, such as coke-oven and aluminium workers and those exposed to coal tar fumes and soot, etc., with the aim of identifying subjects who are susceptible due to the high concentrations of carcinogens found in their working environment.

A 3' untranslated region polymorphism rs2304277 in the DNA repair pathway gene OGG1 is a novel risk modulator for urothelial bladder carcinoma.

PubMed

Ahmed, Tayyaba; Nawaz, Saira; Noreen, Rabia; Bangash, Kashif Sardar; Rauf, Abdur; Younis, Muhammad; Anwar, Khursheed; Khawaja, Muhammad Athar; Azam, Maleeha; Qureshi, Abid Ali; Akhter, Saeed; Kiemeney, Lambertus A; Qamar, Raheel; Ali, Syeda Hafiza Benish

2018-03-01

Altered DNA repair capacity may affect an individual's susceptibility to cancers due to compromised genomic integrity. This study was designed to elucidate the association of selected polymorphisms in DNA repair genes with urothelial bladder carcinoma (UBC). OGG1 rs1052133 and rs2304277, XRCC1 rs1799782 and rs25487, XRCC3 rs861539, XPC rs2228001, and XPD rs13181 were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 200 UBC cases and 200 controls. We found association of OGG1 rs2304277 [odds ratio (OR) GG = 3.55, 95% confidence interval (CI) = 1.79-7.06] and XPC rs2228001 (OR AC = 2.38, 95% CI = 1.43-3.94) with UBC. In stratified analysis with respect to smoking status, OGG1 rs2304277 and XPC rs2228001 exhibited increased risk in smokers [(rs2304277 OR GG = 4.96, 95% CI = 1.51-16.30) (rs2228001 OR AC = 2.19, 95% CI = 1.02-4.72)] as well as nonsmokers [(rs2304277 OR GG = 2.95, 95% CI = 1.26-6.90) (rs2228001 OR AC = 2.57, 95% CI = 1.31-5.04)]. These polymorphisms were also associated with both low-grade [(rs2304277 OR GG = 3.73, 95% CI = 1.72-8.09) (rs2228001 OR AC = 2.18, 95% CI = 1.21-3.92)] and high-grade tumors [(rs2304277 OR GG = 3.45, 95% CI = 1.52-7.80) (rs2228001 OR AC = 2.81, 95% CI = 1.48-5.33)] as well as with non-muscle-invasive bladder cancer [(rs2304277 OR GG = 4.03, 95% CI = 1.87-8.67) (rs2228001 OR AC = 2.14, 95% CI = 1.20-3.81)] and muscle-invasive bladder cancer [(rs2304277 OR GG = 3.06, 95%CI = 1.31-7.13) (rs2228001 OR AC = 2.95, 95%CI = 1.51-5.75)]. This is the first study on DNA repair gene polymorphisms and UBC in the Pakistani population. It identifies OGG1 rs2304277 and replicates XPC rs2228001 as significant modulators of UBC susceptibility. © 2017 John Wiley & Sons Ltd/University College London.

Association between methylenetetrahydrofolate reductase polymorphism C677T and risk of chronic myeloid leukemia in Serbian population.

PubMed

Jakovljevic, Ksenija; Malisic, Emina; Cavic, Milena; Radulovic, Sinisa; Jankovic, Radmila

2012-07-01

Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme regulating the intracellular folate metabolism which plays an important role in carcinogenesis through DNA methylation and nucleotide synthesis. The common MTHFR single nucleotide polymorphism C677T has been reported to be associated with reduced enzymatic activity. In order to investigate the influence of this polymorphism on the risk of chronic myeloid leukemia (CML), we performed a case-control study in a Serbian population of 52 patients with CML and 53 healthy control subjects. MTHFR C677T polymorphism genotyping was assessed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The results demonstrated no statistical difference in MTHFR 677 frequency distribution between patient and control groups. Our findings suggest that MTHFR 677 gene variants have no significant influence on the susceptibility to CML in a Serbian population.

Frequency distribution of polymorphisms of CYP2C19, CYP2C9, VKORC1 and SLCO1B1 genes in the Yakut population.

PubMed

Vasilyev, Filipp Filippovich; Danilova, Diana Aleksandrovna; Kaimonov, Vladimir Sergeevich; Chertovskih, Yana Valerievna; Maksimova, Nadezda Romanovna

2016-01-01

Allele frequencies of single nucleotide polymorphisms (SNPs) are variable among different populations; therefore the study of SNPs in ethnic groups is important for establishing the clinical significance of the screening of these polymorphisms. The main goal of the research is to study the polymorphisms of CYP2C9, CYP2C19, VKORC1, and SLCO1B1 in Yakuts. Genomic DNA from 229 Yakut subjects were analyzed by real-time polymerase chain reaction (PCR) (SLCO1B1 +521T > C, VKORC1 -1639G>A, CYP2C19 +681G>A, +636G>A, CYP2C9 +430С>T, +1075A>C). Genotype frequencies of polymorphisms in the population of the Yakuts were more characteristic of the Asian population. The results have been included in the software application "Lekgen" that we developed for the interpretation of pharmacogenetic testing. The data of our study obtained on frequency carriers of polymorphisms of genes SLCO1B1, CYP2C19, CYP2C9, VKORC1 among the Yakuts may be useful in developing recommendations for a personalized therapy.

Frequency distribution of polymorphisms of CYP2C19, CYP2C9, VKORC1 and SLCO1B1 genes in the Yakut population

PubMed Central

Vasilyev, Filipp Filippovich; Danilova, Diana Aleksandrovna; Kaimonov, Vladimir Sergeevich; Chertovskih, Yana Valerievna; Maksimova, Nadezda Romanovna

2016-01-01

Allele frequencies of single nucleotide polymorphisms (SNPs) are variable among different populations; therefore the study of SNPs in ethnic groups is important for establishing the clinical significance of the screening of these polymorphisms. The main goal of the research is to study the polymorphisms of CYP2C9, CYP2C19, VKORC1, and SLCO1B1 in Yakuts. Genomic DNA from 229 Yakut subjects were analyzed by real-time polymerase chain reaction (PCR) (SLCO1B1 +521T > C, VKORC1 -1639G>A, CYP2C19 +681G>A, +636G>A, CYP2C9 +430С>T, +1075A>C). Genotype frequencies of polymorphisms in the population of the Yakuts were more characteristic of the Asian population. The results have been included in the software application “Lekgen” that we developed for the interpretation of pharmacogenetic testing. The data of our study obtained on frequency carriers of polymorphisms of genes SLCO1B1, CYP2C19, CYP2C9, VKORC1 among the Yakuts may be useful in developing recommendations for a personalized therapy. PMID:27499796

Methylenetetrahydrofolate reductase C677T and A1298C gene polymorphisms and therapy-related toxicity in children treated for acute lymphoblastic leukemia and non-Hodgkin lymphoma.

PubMed

Kantar, Mehmet; Kosova, Buket; Cetingul, Nazan; Gumus, Sevinc; Toroslu, Ertug; Zafer, Nur; Topcuoglu, Nejat; Aksoylar, Serap; Cinar, Mehtap; Tetik, Asli; Eroglu, Zuhal

2009-06-01

This study aimed to investigate the association of the methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C polymorphisms with serum drug levels and toxicities after high-dose methotrexate (MTX) infusion. The study included 37 children with acute lymphoblastic leukemia or non-Hodgkin lymphoma. Serum MTX levels and toxicities of bone marrow, liver and kidney were analysed. Genotype analysis of the C677T and A1298C gene polymorphisms from genomic DNA of the subjects was performed by real-time PCR. Subjects with MTHFR polymorphism for C677T (CT, TT) had significantly higher MTX levels at 24 h (p = 0.009), and these genotypes did not seem to cause toxicity. Subjects with MTHFR polymorphism for A1298C (AC, CC) had significantly higher MTX levels at 48 h (p = 0.02), and had more grade III/IV anemia (p = 0.02), thrombocytopenia (p = 0.0001), elevated AST levels (p = 0.04) and frequent febrile neutropenic episodes (p = 0.004). The present study suggests that A1298C gene, but not C677T polymorphism is associated with MTX-related toxicity.

Polymorphisms and allele frequencies of the ABO blood group gene among the Jomon, Epi-Jomon and Okhotsk people in Hokkaido, northern Japan, revealed by ancient DNA analysis.

PubMed

Sato, Takehiro; Kazuta, Hisako; Amano, Tetsuya; Ono, Hiroko; Ishida, Hajime; Kodera, Haruto; Matsumura, Hirofumi; Yoneda, Minoru; Dodo, Yukio; Masuda, Ryuichi

2010-10-01

To investigate the genetic characteristics of the ancient populations of Hokkaido, northern Japan, polymorphisms of the ABO blood group gene were analyzed for 17 Jomon/Epi-Jomon specimens and 15 Okhotsk specimens using amplified product-length polymorphism and restriction fragment length polymorphism analyses. Five ABO alleles were identified from the Jomon/ Epi-Jomon and Okhotsk people. Allele frequencies of the Jomon/Epi-Jomon and Okhotsk people were compared with those of the modern Asian, European and Oceanic populations. The genetic relationships inferred from principal component analyses indicated that both Jomon/Epi-Jomon and Okhotsk people are included in the same group as modern Asian populations. However, the genetic characteristics of these ancient populations in Hokkaido were significantly different from each other, which is in agreement with the conclusions from mitochondrial DNA and ABCC11 gene analyses that were previously reported.

The Science and Issues of Human DNA Polymoprhisms: A Training Workshop for High School Biology Teachers

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

Interleukin 17 receptor gene polymorphism in periimplantitis and chronic periodontitis.

PubMed

Kadkhodazadeh, Mahdi; Ebadian, Ahmad Reza; Amid, Reza; Youssefi, Navid; Mehdizadeh, Amir Reza

2013-07-13

Gene polymorphism of cytokines influencing their function has been known as a contributing factor in the pathogenesis of inflammatory diseases of the tooth and implant supporting tissues. The aim of this study was to investigate the association of IL-17R gene polymorphism (rs879576) with chronic periodontitis and periimplantitis in an Iranian population. 73 patients with chronic periodontitis, 37 patients with periimplantitis and 83 periodontally healthy patients were enrolled in this study. 5cc blood was obtained from each subject's arm vein and transferred to tubes containing EDTA. Genomic DNA was extracted using Miller's Salting Out technique. The DNA was transferred into 96 division plates, transported to Kbioscience Institute in United Kingdom and analyzed using the Kbioscience Competitive Allele Specific PCR (KASP) technique. Chi-square and Kruskal Wallis tests were used to analyze differences in the expression of genotypes and frequency of alleles in disease and control groups (P-Value less than 0.05 was considered statistically significant). There were no significant differences between periodontitis, periimplantitis with AA, GG, GA genotype of IL-17R gene (P=0.8239). Also comparison of frequency of alleles in SNP rs879576 of IL-17R gene between the chronic periodontitis group and periimplantitis group did not revealed statistically significant differences (P=0.8239). The enigma of IL-17 and its polymorphism-role in periodontitis and periimplantitis is yet to be investigated more carefully throughout further research but this article demonstrates that polymorphism of IL-17R plays no significant role in incidence of chronic periodontitis and Periimplantitis.

Molecular marker-based genetic diversity analysis of scantly studied Brazilian accessions of a medicinal plant, Morinda citrifolia L. (noni).

PubMed

Bordallo, P N; Monteiro, A M R; Sousa, J A; Aragão, F A S

2017-02-23

Morinda citrifolia L., commonly known as noni, has been used for the treatment of various diseases for over two centuries. It was introduced and widely disseminated in Brazil because of its high market value and ease of adaptation to the soil and climatic conditions of the country. The aim of this study was to estimate the genetic variability of noni accessions from the collection of Embrapa Agroindústria Tropical in Brazil. We evaluated 36 plants of the 13 accessions of noni from the germplasm collection of M. citrifolia. Several methods of DNA extraction were tested. After definition of the method, the DNA of each sample was subjected to polymerase chain reactions using 20 random amplified polymorphic DNA primers. The band patterns on agarose gel were converted into a binary data matrix, which was used to estimate the genetic distances between the plants and to perform the cluster analyses. Of the total number of markers used in this study, 125 (81.1%) were polymorphic. The genetic distances between the genotypes ranged from 0.04 to 0.49. Regardless of the high number of polymorphic bands, the genetic variability of the noni plants evaluated was low since most of the genotypes belonged to the same cluster as shown by the dendrogram and Tocher's cluster analysis. The low genetic diversity among the studied noni individuals indicates that additional variability should be introduced in the germplasm collection of noni by gathering new individuals and/or by hybridizing contrasting individuals.

Polymorphism of MDM2 promoter 309 (rs 2279744) and the risk of PCOS.

PubMed

Chan, Ying; Jiang, Hongguo; Yang, Xiaoling; Li, Dongya; Ma, Lan; Luo, Ying; Tang, Wenru

2016-01-01

This study aimed at evaluating possible association between MDM2 SNP309 polymorphism (rs 2279744) and polycystic ovary syndrome (PCOS). One hundred and twenty-five women with PCOS and two hundred and fifty women without PCOS were collected from the department of reproductive medicine of college hospital in this case-control study. Peripheral blood samples were collected from all participants and DNA was extracted, MDM2 SNP309 polymorphism (rs 2279744) was determined from the 125 cases and 250 controls. Women were grouped into PCOS (n = 125) group and control group (n = 250). Odds ratios (OR) and 95% confidence intervals (CI) were used to evaluate the association between MDM2 SNP309 polymorphism (rs 2279744) and PCOS. The distribution of T allele was significant higher in PCOS cases than controls. MDM2 SNP 309 T allele is associated with PCOS.

Association between Single Nucleotide Polymorphism of Vitamin D Receptor Gene FokI Polymorphism and Clinical Progress of Benign Prostatic Hyperplasia

PubMed Central

Ruan, Li; Zhu, Jian-guo; Pan, Cong; Hua, Xing; Yuan, Dong-bo; Li, Zheng-ming; Zhong, Wei-de

2015-01-01

Background. The aim of the study was to investigate the association between single nucleotide polymorphism (SNP) of vitamin D receptor (VDR) gene and clinical progress of benign prostatic hyperplasia (BPH) in Chinese men. Methods. The DNA was extracted from blood of 200 BPH patients with operation (progression group) and 200 patients without operation (control group), respectively. The genotypes of VDR gene FokI SNP represented by “F/f” were identified by PCR-restriction fragment length polymorphism. The odds ratio (OR) of having progression of BPH for having the genotype were calculated. Results. Our date indicated that the f alleles of the VDR gene FokI SNP associated with the progression of BPH (P = 0.009). Conclusion. For the first time, our study demonstrated that VDR gene FokI SNP may be associated with the risk of BPH progress. PMID:25685834

Lack of association between the APEX1 Asp148Glu polymorphism and sporadic amyotrophic lateral sclerosis.

PubMed

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.

RAPD and SSR Polymorphisms in Mutant Lines of Transgenic Wheat Mediated by Low Energy Ion Beam

NASA Astrophysics Data System (ADS)

Wang, Tiegu; Huang, Qunce; Feng, Weisen

2007-10-01

Two types of markers-random amplified polymorphic DNA (RAPD) and simple sequence repeat DNA (SSR)-have been used to characterize the genetic diversity among nine mutant lines of transgenic wheat intermediated by low energy ion beam and their four receptor cultivars. The objectives of this study were to analyze RAPD-based and SSR-based genetic variance among transgenic wheat lines and with their receptors, and to find specific genetic markers of special traits of transgenic wheat lines. 170 RAPD primers were amplified to 733 fragments in all the experimental materials. There were 121 polymorphic fragments out of the 733 fragments with a ratio of polymorphic fragments of 16.5%. 29 SSR primer pairs were amplified to 83 fragments in all the experiment materials. There were 57 polymorphic fragments out of the 83 fragments with a ratio of polymorphic fragments of 68.7%. The dendrograms were prepared based on a genetic distance matrix using the UPGMA (Unweighted Pair-group Method with Arithmetic averaging) algorithm, which corresponded well to the results of the wheat pedigree analysis and separated the 13 genotypes into four groups. Association analysis between RAPD and SSR markers with the special traits of transgenic wheat mutant lines discovered that three RAPD markers, s1, opt-16, and f14, were significantly associated with the muticate trait, while three SSR markers, Rht8 (Xgwm261), Rht-B1b, and Rht-D1b, highly associated with the dwarf trait. These markers will be useful for marker-assistant breeding and can be used as candidate markers for further gene mapping and cloning.

A Population Genetics Study of Anopheles Darlingi (Diptera: Culicidae) from Colombia Based on Random Amplified Polymorphic DNA-Polymerase Chain Reaction and Amplified Fragment Length Polymorphism Markers

DTIC Science & Technology

2007-06-01

Biology of Disease Vectors, University Press of Colorado. Niwot, co. p. 417-437. Tadei WI’, Santos JMN, Rabbani MG 1982. Biologia de anofelinos amazonicos...wR 4𔃼.0 Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 102(3): 255-262, June 2007 255 A population genetics study ofAnopheles darlingi (Diptera... de Ciencias y rdcullad de Salud. Universidad del Valle, (’.ali, Colombia *Depanment of Entomology, Walter Reed Army Institute of Research. Silver

Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms

DTIC Science & Technology

2005-07-01

folate, and metabolic gene polymorphisms in relation to breast cancer risk: Months 1-19. b. Prepare blood samples for relevant assays: Months 1-19... gene polymorphism assays among the 184 cases and matched controls. The folate assays are on-going at this time. DNA assays will commence in the... methotrexate . Ann Oncol 13: 1915–1918, 2002 13. Toffoli G, Veronesi A, Boiocchi M, Crivellari D: MTHFR gene polymorphism and severe toxicity during

Restriction fragment length polymorphism of the major histocompatibility complex of the dog.

PubMed

Sarmiento, U M; Storb, R F

1988-01-01

Human major histocompatibility complex (HLA) cDNA probes were used to analyze the restriction fragment length polymorphism (RFLP) of the DLA-D region in dogs. Genomic DNA from peripheral blood leucocytes of 23 unrelated DLA-D-homozygous dogs representing nine DLA-D types (defined by mixed leucocyte reaction) was digested with restriction enzymes (Bam HI, Eco RI, Hind III, Pvu II, Taq I, Rsa I, Msp I, Pst I, and Bgl II), separated by agarose gel electrophoresis, and transferred onto Biotrace membrane. The Southern blots were successively hybridized with radiolabeled HLA cDNA probes corresponding to DR, DQ, DP, and DO beta genes. The autoradiograms for all nine enzyme digests displayed multiple bands with the DRb, DQb, and DPb probes while the DOb probe hybridized with one to two bands. The RFLP patterns were highly polymorphic but consistent within each DLA-D type. Standard RFLP patterns were established for nine DLA-D types which could be discriminated from each other by using two enzymes (Rsa I and Pst I) and the HLA-DPb probe. Cluster analysis of the polymorphic restriction fragments detected by the DRb probe revealed four closely related supertypic groups or DLA-DR families: Dw3 + Dw4 + D1, Dw8 + D10, D7 + D16 + D9, and Dw1. This study provides the basis for DLA-D genotyping at a population level by RFLP analysis. These results also suggest that the genetic organization of the DLA-D region may closely resemble that of the HLA complex.

Development of highly polymorphic EST-SSR markers and segregation in F₁ hybrid population of Vitis vinifera L.

PubMed

Kayesh, E; Zhang, Y Y; Liu, G S; Bilkish, N; Sun, X; Leng, X P; Fang, J G

2013-09-23

The objectives of this investigation were to develop and validate the expressed sequence tag (EST)-simple sequence repeat (SSR) markers from large EST sequences, and to study the segregation and distribution of SSRs within two grapevine parental lines. In total, 94 F₁ lines crossed between "Early Rose" and "Red Globe" were studied. Approximately 2100 EST-SSR sequences of Vitis vinifera L. were searched for SSRs and analyzed for the design of polymerase chain reaction (PCR) primers amplifying the SSR-rich regions. Trinucleotide repeats were found to be the most abundant, followed by other nucleotide repeats. A total of 182 SSR primer pairs were first developed for the study on the parental polymorphism. Among the 182 SSR primers, 142 primer pairs (78%) could amplify the anticipated PCR products, among which only 52 primer pairs (36.62%) showed polymorphism between the two parents. These polymorphic bands were further surveyed among the 94 F₁ lines, and the results showed that a total of 162 bands were amplified, and 98 of them were polymorphic in both parents (60.86% polymorphism), with an average of 1.88 polymorphic DNA bands for each primer pair. After testing with the chi-square test, 33 of the clearly amplified polymorphic bands followed a 3:1 ratio, and 37 followed a 1:1 ratio. The rest showed distorted segregation ratios.

An improved in silico selection of phenotype affecting polymorphisms in SLC6A4, HTR1A and HTR2A genes.

PubMed

Piva, Francesco; Giulietti, Matteo; Nardi, Bernardo; Bellantuono, Cesario; Principato, Giovanni

2010-03-01

Among the experimentally assessed DNA variations in serotonin related genes, some influence physiological expression of personality and mental disorders, others alter the responses to pharmacological and/or psychotherapeutic treatments. Because of the huge number of polymorphisms lying in genes and of the great length of time necessary to perform association studies, a selection of the variations being studied is a necessary and crucial step. In this work we used the most updated and assessed bioinformatic tools to predict the phenotype affecting polymorphisms of the human HTR1A, HTR2A and SLC6A4 serotonin related genes. Moreover, we carried out a literature search to collect information about the recent association studies to compare it versus our prediction data. Gene polymorphism analysis indicated the variations that are worth considering in the association studies in the field of psychiatry, psychology and pharmacogenomics. The literature revision allowed to show both the few well and the most not enough investigated polymorphisms. Our data can be useful to select polymorphisms for new association studies, especially those not yet investigated that can be related to behaviour, mental disorders and individual treatment response. Copyright 2010 John Wiley & Sons, Ltd.

Comparison of Haemophilus parasuis reference strains and field isolates by using random amplified polymorphic DNA and protein profiles

PubMed Central

2012-01-01

Background Haemophilus parasuis is the causative agent of Glässer’s disease and is a pathogen of swine in high-health status herds. Reports on serotyping of field strains from outbreaks describe that approximately 30% of them are nontypeable and therefore cannot be traced. Molecular typing methods have been used as alternatives to serotyping. This study was done to compare random amplified polymorphic DNA (RAPD) profiles and whole cell protein (WCP) lysate profiles as methods for distinguishing H. parasuis reference strains and field isolates. Results The DNA and WCP lysate profiles of 15 reference strains and 31 field isolates of H. parasuis were analyzed using the Dice and neighbor joining algorithms. The results revealed unique and reproducible DNA and protein profiles among the reference strains and field isolates studied. Simpson’s index of diversity showed significant discrimination between isolates when three 10mer primers were combined for the RAPD method and also when both the RAPD and WCP lysate typing methods were combined. Conclusions The RAPD profiles seen among the reference strains and field isolates did not appear to change over time which may reflect a lack of DNA mutations in the genes of the samples. The recent field isolates had different WCP lysate profiles than the reference strains, possibly because the number of passages of the type strains may affect their protein expression. PMID:22703293

Chemoraces and Habitat Specialization of Claviceps purpurea Populations

PubMed Central

Pažoutová, Sylvie; Olšovská, Jana; Linka, Marek; Kolínská, Renata; Flieger, Miroslav

2000-01-01

We studied genetic variability of 100 isolates of Claviceps purpurea by using randomly amplified polymorphic DNA (RAPD), an EcoRI restriction site polymorphism in the 5.8S ribosomal DNA (rDNA), the alkaloids produced, and conidial morphology. We identified three groups: (i) group G1 from fields and open meadows (57 isolates), (ii) group G2 from shady or wet habitats (41 isolates), and (iii) group G3 from Spartina anglica from salt marshes (2 isolates). The sclerotia of G1 isolates contained ergotamines and ergotoxines; G2 isolates produced ergosine and ergocristine along with small amounts of ergocryptine; and G3 isolates produced ergocristine and ergocryptine. The conidia of G1 isolates were 5 to 8 μm long, the conidia of G2 isolates were 7 to 10 μm long, and the conidia of G3 isolates were 10 to 12 μm long. Sclerotia of the G2 and G3 isolates floated on water. In the 5.8S rDNA analysis, an EcoRI site was found in G1 and G3 isolates but not in G2 isolates. The host preferences of the groups were not absolute, and there were host genera that were common to both G1 and G2; the presence of members of different groups in the same locality was rare. Without the use of RAPD or rDNA polymorphism, it was not possible to distinguish the three groups solely on the basis of phenotype, host, or habitat. In general, populations of C. purpurea are not host specialized, as previously assumed, but they are habitat specialized, and collecting strategies and toxin risk assessments should be changed to reflect this paradigm shift. PMID:11097923

Comprehensive Survey of Genetic Diversity in Chloroplast Genomes and 45S nrDNAs within Panax ginseng Species

PubMed Central

Kim, Kyunghee; Lee, Sang-Choon; Lee, Junki; Lee, Hyun Oh; Joh, Ho Jun; Kim, Nam-Hoon; Park, Hyun-Seung; Yang, Tae-Jin

2015-01-01

We report complete sequences of chloroplast (cp) genome and 45S nuclear ribosomal DNA (45S nrDNA) for 11 Panax ginseng cultivars. We have obtained complete sequences of cp and 45S nrDNA, the representative barcoding target sequences for cytoplasm and nuclear genome, respectively, based on low coverage NGS sequence of each cultivar. The cp genomes sizes ranged from 156,241 to 156,425 bp and the major size variation was derived from differences in copy number of tandem repeats in the ycf1 gene and in the intergenic regions of rps16-trnUUG and rpl32-trnUAG. The complete 45S nrDNA unit sequences were 11,091 bp, representing a consensus single transcriptional unit with an intergenic spacer region. Comparative analysis of these sequences as well as those previously reported for three Chinese accessions identified very rare but unique polymorphism in the cp genome within P. ginseng cultivars. There were 12 intra-species polymorphisms (six SNPs and six InDels) among 14 cultivars. We also identified five SNPs from 45S nrDNA of 11 Korean ginseng cultivars. From the 17 unique informative polymorphic sites, we developed six reliable markers for analysis of ginseng diversity and cultivar authentication. PMID:26061692

Identification of Species Related to Anopheles (Nyssorhynchus) albitarsis by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (Diptera: Culicidae)

DTIC Science & Technology

1995-11-01

Instituto de Biologia do ExCrcito, Rua Francisco Manuel 102, 2091 l-270 Rio de Janeiro, RJ, Brasil Species-specific Random Amplified Polymorphic DNA...da Panela Manaus Ilha Comprida 6 km SW Registro Ponte Melo Peixoto Capanema Ilha de Marajo Santa Helena nr. Guaira Aguia Branca Rio Socuavo...Brazil; 11, Ponte Melo Peixoto, Brazil. Fig. 3: RAPD amplifications of Albitarsis Complex species A with primer B05. Arrow on left indicates fragment

Identification of hallucinogenic fungi from the genera Psilocybe and Panaeolus by amplified fragment length polymorphism.

PubMed

Lee, J C; Cole, M; Linacre, A

2000-05-01

Unambiguous identification of the hallucinogenic fungi of the genera Psilocybe and Panaeolus is required by national and international drug control legislation. We report on a DNA-based test using the technique of amplified fragment length polymorphism (AFLP). AFLP can differentiate species of the two genera Psilocybe and Panaeolus by using different primer sets. The identification of hallucinogenic fungi using a DNA-based test, which can be used in conjunction with morphological features, will assist in forensic investigations.

The occurrence of Toxocara malaysiensis in cats in China, confirmed by sequence-based analyses of ribosomal DNA.

PubMed

Li, Ming-Wei; Zhu, Xing-Quan; Gasser, Robin B; Lin, Rui-Qing; Sani, Rehana A; Lun, Zhao-Rong; Jacobs, Dennis E

2006-10-01

Non-isotopic polymerase chain reaction (PCR)-based single-strand conformation polymorphism and sequence analyses of the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) were utilized to genetically characterise ascaridoids from dogs and cats from China by comparison with those from other countries. The study showed that Toxocara canis, Toxocara cati, and Toxascaris leonina from China were genetically the same as those from other geographical origins. Specimens from cats from Guangzhou, China, which were morphologically consistent with Toxocara malaysiensis, were the same genetically as those from Malaysia, with the exception of a polymorphism in the ITS-2 but no unequivocal sequence difference. This is the first report of T. malaysiensis in cats outside of Malaysia (from where it was originally described), supporting the proposal that this species has a broader geographical distribution. The molecular approach employed provides a powerful tool for elucidating the biology, epidemiology, and zoonotic significance of T. malaysiensis.

Non-concerted ITS evolution in Mammillaria (Cactaceae).

PubMed

Harpke, Doerte; Peterson, Angela

2006-12-01

Molecular studies of 21 species of the large Cactaceae genus Mammillaria representing a variety of intrageneric taxonomic levels revealed a high degree of intra-individual polymorphism of the internal transcribed spacer region (ITS1, 5.8S rDNA, ITS2). Only a few of these ITS copies belong to apparently functional genes, whereas most are probably non-functional (pseudogenes). As a multiple gene family, the ITS region is subjected to concerted evolution. However, the high degree of intra-individual polymorphism of up to 36% in ITS1 and up to 35% in ITS2 suggests a non-concerted evolution of these loci in Mammillaria. Conserved angiosperm motifs of ITS1 and ITS2 were compared between genomic and cDNA ITS clones of Mammillaria. Some of these motifs (e.g., ITS1 motif 1, 'TGGT' within ITS2) in combination with the determination of GC-content, length comparisons of the spacers and ITS2 secondary structure (helices II and III) are helpful in the identification of pseudogene rDNA regions.

A comparative genetic analysis of the Irish greyhound population using multilocus DNA fingerprinting, canine single locus minisatellites and canine microsatellites.

PubMed

Sutton, M D; Holmes, N G; Brennan, F B; Binns, M M; Kelly, E P; Duke, E J

1998-06-01

Pairwise analysis of HinfI/33.6 DNA fingerprints from a total of one hundred and fifty-three Irish greyhounds of known pedigree were used to determine band-share estimates of unrelated, first-degree and second-degree relationships. Forty-eight unrelated Irish greyhounds were used to determine allele frequencies for three single-locus minisatellites, and following a preliminary screen, eight of the most polymorphic tetra-nucleotide microsatellites from a panel of 15. The results indicated that both band-share estimates by DNA fingerprinting and microsatellite allele frequencies are highly effective in resolving parentage in this greyhound population, while single-locus minisatellites showed limited polymorphism and could not be used alone for routine parentage testing in this breed. The present study also demonstrated that, to obtain optimal resolution of parentage, sample sets of known pedigree status are required to determine the band-share distribution and/or microsatellite allele frequencies.

Analysis on the DNA Fingerprinting of Aspergillus Oryzae Mutant Induced by High Hydrostatic Pressure

NASA Astrophysics Data System (ADS)

Wang, Hua; Zhang, Jian; Yang, Fan; Wang, Kai; Shen, Si-Le; Liu, Bing-Bing; Zou, Bo; Zou, Guang-Tian

2011-01-01

The mutant strains of aspergillus oryzae (HP300a) are screened under 300 MPa for 20 min. Compared with the control strains, the screened mutant strains have unique properties such as genetic stability, rapid growth, lots of spores, and high protease activity. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) are used to analyze the DNA fingerprinting of HP300a and the control strains. There are 67.9% and 51.3% polymorphic bands obtained by these two markers, respectively, indicating significant genetic variations between HP300a and the control strains. In addition, comparison of HP300a and the control strains, the genetic distances of random sequence and simple sequence repeat of DNA are 0.51 and 0.34, respectively.

Single nucleotide polymorphism analysis using different colored dye dimer probes

NASA Astrophysics Data System (ADS)

Marmé, Nicole; Friedrich, Achim; Denapaite, Dalia; Hakenbeck, Regine; Knemeyer, Jens-Peter

2006-09-01

Fluorescence quenching by dye dimer formation has been utilized to develop hairpin-structured DNA probes for the detection of a single nucleotide polymorphism (SNP) in the penicillin target gene pbp2x, which is implicated in the penicillin resistance of Streptococcus pneumoniae. We designed two specific DNA probes for the identification of the pbp2x genes from a penicillin susceptible strain R6 and a resistant strain Streptococcus mitis 661 using green-fluorescent tetramethylrhodamine (TMR) and red-fluorescent DY-636, respectively. Hybridization of each of the probes to its respective target DNA sequence opened the DNA hairpin probes, consequently breaking the nonfluorescent dye dimers into fluorescent species. This hybridization of the target with the hairpin probe achieved single nucleotide specific detection at nanomolar concentrations via increased fluorescence.

Hospital strain colonization by Staphylococcus epidermidis.

PubMed

Blum-Menezes, D; Bratfich, O J; Padoveze, M C; Moretti, M L

2009-03-01

The skin and mucous membranes of healthy subjects are colonized by strains of Staphylococcus epidermidis showing a high diversity of genomic DNA polymorphisms. Prolonged hospitalization and the use of invasive procedures promote changes in the microbiota with subsequent colonization by hospital strains. We report here a patient with prolonged hospitalization due to chronic pancreatitis who was treated with multiple antibiotics, invasive procedures and abdominal surgery. We studied the dynamics of skin colonization by S. epidermidis leading to the development of catheter-related infections and compared the genotypic profile of clinical and microbiota strains by pulsed field gel electrophoresis. During hospitalization, the normal S. epidermidis skin microbiota exhibiting a polymorphic genomic DNA profile was replaced with a hospital-acquired biofilm-producer S. epidermidis strain that subsequently caused repetitive catheter-related infections.

HPA AXIS RELATED GENES AND RESPONSE TO PSYCHOLOGICAL THERAPIES: GENETICS AND EPIGENETICS

PubMed Central

Roberts, Susanna; Keers, Robert; Lester, Kathryn J; Coleman, Jonathan R. I.; Breen, Gerome; Arendt, Kristian; Blatter‐Meunier, Judith; Cooper, Peter; Creswell, Cathy; Fjermestad, Krister; Havik, Odd E.; Herren, Chantal; Hogendoorn, Sanne M.; Hudson, Jennifer L.; Krause, Karen; Lyneham, Heidi J.; Morris, Talia; Nauta, Maaike; Rapee, Ronald M.; Rey, Yasmin; Schneider, Silvia; Schneider, Sophie C.; Silverman, Wendy K.; Thastum, Mikael; Thirlwall, Kerstin; Waite, Polly

2015-01-01

Background Hypothalamic–pituitary–adrenal (HPA) axis functioning has been implicated in the development of stress‐related psychiatric diagnoses and response to adverse life experiences. This study aimed to investigate the association between genetic and epigenetics in HPA axis and response to cognitive behavior therapy (CBT). Methods Children with anxiety disorders were recruited into the Genes for Treatment project (GxT, N = 1,152). Polymorphisms of FKBP5 and GR were analyzed for association with response to CBT. Percentage DNA methylation at the FKBP5 and GR promoter regions was measured before and after CBT in a subset (n = 98). Linear mixed effect models were used to investigate the relationship between genotype, DNA methylation, and change in primary anxiety disorder severity (treatment response). Results Treatment response was not associated with FKBP5 and GR polymorphisms, or pretreatment percentage DNA methylation. However, change in FKBP5 DNA methylation was nominally significantly associated with treatment response. Participants who demonstrated the greatest reduction in severity decreased in percentage DNA methylation during treatment, whereas those with little/no reduction in severity increased in percentage DNA methylation. This effect was driven by those with one or more FKBP5 risk alleles, with no association seen in those with no FKBP5 risk alleles. No significant association was found between GR methylation and response. Conclusions Allele‐specific change in FKBP5 methylation was associated with treatment response. This is the largest study to date investigating the role of HPA axis related genes in response to a psychological therapy. Furthermore, this is the first study to demonstrate that DNA methylation changes may be associated with response to psychological therapies in a genotype‐dependent manner. PMID:26647360

Gene analysis of steroid 5 alpha-reductase 1 in hyperandrogenic women.

PubMed

Eminović, Izet; Komel, Radovan; Prezelj, Janez; Karamehić, Jasenko; Gavrankapetanović, Faris; Heljić, Becir

2005-08-01

To examine the gene encoding for 5alpha-reductase type 1 in hyperandrogenic women, and assess the association of its eventual mutations or polymorphisms with the development of the hyperandrogenic female pattern. Sixteen hyperandrogenic women were included in the study. Single-stranded conformation polymorphism analysis (SSCP) and DNA sequencing were performed after polymerase chain reaction amplification of each of the 5 exons of the SRD5A1 gene in both hyperandrogenic and control group (16 participants). Sequence analysis identified the existence of many polymorphisms; in codon 24 of exon 1, GGC (Gly) into GAC (Asp); in codon 30 of exon 1, CGG (Arg) into CGC (Arg); in exon 3 codon 169, ACA to ACG (both encoding for threonine); in exon 5, AGA to AGG (both encoding for arginine, codon 260); and T/C polymorphism in intron 2. Polymorphisms were found in both groups. Polymorphisms of SRD5A1 gene were the same in both hyperandrogenic and healthy women, indicating no significant associations of genetic polymorphisms/variations of SRD5A1 gene with clinical manifestations of hyperandrogenic disorders in women.

Polymorphism of heat shock protein 70-2 and enterocutaneous fistula in Chinese population

PubMed Central

Chen, Jun; Ren, Jian-An; Han, Gang; Gu, Guo-Sheng; Wang, Ge-Fei; Wu, Xiu-Wen; Zhou, Bo; Hu, Dong; Wu, Yin; Zhao, Yun-Zhao; Li, Jie-Shou

2014-01-01

AIM: To investigate whether the heat shock protein 70-2 (HSP70-2) polymorphism is associated with enterocutaneous fistulas in a Chinese population. METHODS: This study included 131 patients with enterocutaneous/enteroatmospheric fistulas. Patients with inflammatory bowel disease or other autoimmune diseases were excluded from this study. All patients with enterocutaneous/enteroatmospheric fistulas were followed up for three months to observe disease recurrence. In addition, a total of 140 healthy controls were also recruited from the Jinling Hospital, matched according to the sex and age of the patient population. Genomic DNA was extracted from peripheral blood from each participant. The HSP70-2 restriction fragment length polymorphism related to the polymorphic PstI site at position 1267 was characterized by polymerase chain reaction (PCR). First PCR amplification was carried out, and then PCR products were digested with PstI restriction enzyme. The DNA lacking the polymorphic PstI site within HSP70-2 generates a product of 1117 bp in size (allele A), whereas the HSP70-2 PstI polymorphism produces two fragments of 936 bp and 181 bp in size (allele B). RESULTS: The frequency of the HSP70-2 PstI polymorphism did not differ between patients and controls; however, the A allele was more predominant in patients with enterocutaneous fistulas than in controls (60.7% vs 51.4%, P = 0.038, OR = 1.425, 95%CI: 1.019-1.994). Sixty-one patients were cured by a definitive operation, drainage operation, or percutaneous drainage while 52 patients were cured by nonsurgical treatment. There was no significant difference in the frequency of the HSP70-2 PstI polymorphism between the patients who had surgery compared to those who did not (P = 0.437, OR = 1.237, 95%CI: 0.723-2.117). Moreover, 11 patients refused any treatment for economic reasons or tumor burden, and 7 patients with enterocutaneous fistulas (5.8%) died during the follow-up period. However, there was no significant difference in the frequency of the HSP70-2 PstI polymorphism between the patients who survived compared to those who died (P = 0.403, OR = 0.604, 95%CI: 0.184-1.986). CONCLUSION: The A allele of the HSP70-2 PstI polymorphism was associated with enterocutaneous fistulas in this Chinese population. PMID:25253958

Frequency of distribution of inflammatory cytokines IL-1, IL-6 and TNF-alpha gene polymorphism in patients with obstructive sleep apnea.

PubMed

Popko, K; Gorska, E; Potapinska, O; Wasik, M; Stoklosa, A; Plywaczewski, R; Winiarska, M; Gorecka, D; Sliwinski, P; Popko, M; Szwed, T; Demkow, U

2008-12-01

Obesity is one of the most commonly identified factors for the obstructive sleep apnea syndrome (OSAS). Adipose tissue is the source of many cytokines, among them there are IL-6, IL-1, and TNF-alpha. The level of inflammatory cytokines increases in people with OSAS and obesity. The aim of this study was to evaluate the distribution of genotypes in inflammatory cytokine genes in people with obesity-related OSAS. The examined group consisted of 102 person with obesity related-OSAS and 77 normal weight person without OSAS. Genotyping of DNA sequence variation was carried out by restriction enzyme (IL-1: Taq I, IL-6: Lwe I, TNF-alpha: Nco I) analysis of PCR amplified DNA. The study revealed a significant correlation between polymorphism located in the promoter region of inflammatory cytokine genes and obesity-related OSAS.

Affordable Hands-On DNA Sequencing and Genotyping: An Exercise for Teaching DNA Analysis to Undergraduates

ERIC Educational Resources Information Center

Shah, Kushani; Thomas, Shelby; Stein, Arnold

2013-01-01

In this report, we describe a 5-week laboratory exercise for undergraduate biology and biochemistry students in which students learn to sequence DNA and to genotype their DNA for selected single nucleotide polymorphisms (SNPs). Students use miniaturized DNA sequencing gels that require approximately 8 min to run. The students perform G, A, T, C…

Heterologous mitochondrial DNA recombination in human cells.

PubMed

D'Aurelio, Marilena; Gajewski, Carl D; Lin, Michael T; Mauck, William M; Shao, Leon Z; Lenaz, Giorgio; Moraes, Carlos T; Manfredi, Giovanni

2004-12-15

Inter-molecular heterologous mitochondrial DNA (mtDNA) recombination is known to occur in yeast and plants. Nevertheless, its occurrence in human cells is still controversial. To address this issue we have fused two human cytoplasmic hybrid cell lines, each containing a distinct pathogenic mtDNA mutation and specific sets of genetic markers. In this hybrid model, we found direct evidence of recombination between these two mtDNA haplotypes. Recombinant mtDNA molecules in the hybrid cells were identified using three independent experimental approaches. First, recombinant molecules containing genetic markers from both parental alleles were demonstrated with restriction fragment length polymorphism of polymerase chain reaction products, by measuring the relative frequencies of each marker. Second, fragments of recombinant mtDNA were cloned and sequenced to identify the regions involved in the recombination events. Finally, recombinant molecules were demonstrated directly by Southern blot using appropriate combinations of polymorphic restriction sites and probes. This combined approach confirmed the existence of heterogeneous species of recombinant mtDNA molecules in the hybrid cells. These findings have important implications for mtDNA-related diseases, the interpretation of human evolution and population genetics and forensic analyses based on mtDNA genotyping.

Estimation of the relationship between the polymorphisms of selected genes: ACE, AGTR1, TGFβ1 and GNB3 with the occurrence of primary vesicoureteral reflux.

PubMed

Życzkowski, Marcin; Żywiec, Joanna; Nowakowski, Krzysztof; Paradysz, Andrzej; Grzeszczak, Władyslaw; Gumprecht, Janusz

2017-03-01

Etiopathogenesis of VUR is composite and not fully understood. Many data indicate the importance of genetic predisposition. The aim of this study was to establish the relationship of selected polymorphisms: 14094 polymorphism of the ACE, polymorphism rs1800469 of TGFβ-1, rs5443 gene polymorphism of the GNB3 and receptor gene polymorphism rs5186 type 1 AGTR1 with the occurrence of the primary vesicoureteral reflux. The study included 190 children: 90 with the primary VUR confirmed with the voiding cystourethrogram and excluded secondary VUR and a control group of 100 children without a history of the diseases of the genitourinary tract. The study was planned in the scheme: "tested case versus control." Genomic DNA was isolated from the leukocytes of peripheral blood samples. The results were statistically analyzed in the Statistica 10 using χ 2 test and analysis of the variance Anova. Any of the four studied polymorphisms showed no difference in the distribution of genotypes between patients with primary vesicoureteral reflux and the control group. In patients with VUR and TT genotype polymorphism rs5443 GNB3 gene, the glomerular filtration rate was significantly higher than in patients with genotype CC or CT. (1) No relationship was found between the studied polymorphisms (14094 ACE gene, rs1800469 gene TGFβ1, GNB3 gene rs5443, rs5186 AGTR1 gene) and the occurrence of primary vesicoureteral reflux. (2) TT genotype polymorphism rs5443 GNB3 gene may be a protective factor for the improved renal function in patients with primary vesicoureteral reflux in patients with genotype CC or CT.

Contrasting Patterns of rDNA Homogenization within the Zygosaccharomyces rouxii Species Complex

PubMed Central

Chand Dakal, Tikam; Giudici, Paolo; Solieri, Lisa

2016-01-01

Arrays of repetitive ribosomal DNA (rDNA) sequences are generally expected to evolve as a coherent family, where repeats within such a family are more similar to each other than to orthologs in related species. The continuous homogenization of repeats within individual genomes is a recombination process termed concerted evolution. Here, we investigated the extent and the direction of concerted evolution in 43 yeast strains of the Zygosaccharomyces rouxii species complex (Z. rouxii, Z. sapae, Z. mellis), by analyzing two portions of the 35S rDNA cistron, namely the D1/D2 domains at the 5’ end of the 26S rRNA gene and the segment including the internal transcribed spacers (ITS) 1 and 2 (ITS regions). We demonstrate that intra-genomic rDNA sequence variation is unusually frequent in this clade and that rDNA arrays in single genomes consist of an intermixing of Z. rouxii, Z. sapae and Z. mellis-like sequences, putatively evolved by reticulate evolutionary events that involved repeated hybridization between lineages. The levels and distribution of sequence polymorphisms vary across rDNA repeats in different individuals, reflecting four patterns of rDNA evolution: I) rDNA repeats that are homogeneous within a genome but are chimeras derived from two parental lineages via recombination: Z. rouxii in the ITS region and Z. sapae in the D1/D2 region; II) intra-genomic rDNA repeats that retain polymorphisms only in ITS regions; III) rDNA repeats that vary only in their D1/D2 domains; IV) heterogeneous rDNA arrays that have both polymorphic ITS and D1/D2 regions. We argue that an ongoing process of homogenization following allodiplodization or incomplete lineage sorting gave rise to divergent evolutionary trajectories in different strains, depending upon temporal, structural and functional constraints. We discuss the consequences of these findings for Zygosaccharomyces species delineation and, more in general, for yeast barcoding. PMID:27501051

Comparison of semi-automated commercial rep-PCR fingerprinting, spoligotyping, 12-locus MIRU-VNTR typing and single nucleotide polymorphism analysis of the embB gene as molecular typing tools for Mycobacterium bovis.

PubMed

Armas, Federica; Camperio, Cristina; Coltella, Luana; Selvaggini, Serena; Boniotti, Maria Beatrice; Pacciarini, Maria Lodovica; Di Marco Lo Presti, Vincenzo; Marianelli, Cinzia

2017-08-04

Highly discriminatory genotyping strategies are essential in molecular epidemiological studies of tuberculosis. In this study we evaluated, for the first time, the efficacy of the repetitive sequence-based PCR (rep-PCR) DiversiLab Mycobacterium typing kit over spoligotyping, 12-locus mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing and embB single nucleotide polymorphism (SNP) analysis for Mycobacterium bovis typing. A total of 49 M. bovis animal isolates were used. DNA was extracted and genomic DNA was amplified using the DiversiLab Mycobacterium typing kit. The amplified fragments were separated and detected using a microfluidics chip with Agilent 2100. The resulting rep-PCR-based DNA fingerprints were uploaded to and analysed using web-based DiversiLab software through Pearson's correlation coefficient. Rep-PCR DiversiLab grouped M. bovis isolates into ten different clusters. Most isolates sharing identical spoligotype, MIRU-VNTR profile or embB gene polymorphism were grouped into different rep-PCR clusters. Rep-PCR DiversiLab displayed greater discriminatory power than spoligotyping and embB SNP analysis but a lower resolution power than the 12-locus MIRU-VNTR analysis. MIRU-VNTR confirmed that it is superior to the other PCR-based methods tested here. In combination with spoligotyping and 12-locus MIRU-VNTR analysis, rep-PCR improved the discriminatory power for M. bovis typing.

Effects of interleukin-1 receptor antagonist (IL-1Ra) gene 86 bp VNTR polymorphism on recurrent pregnancy loss: a case-control study.

PubMed

Hajizadeh, Yasamin Sayed; Emami, Elina; Nottagh, Marina; Amini, Zahra; Maroufi, Nazila Fathi; Azimian, Saba Haj; Isazadeh, Alireza

2017-05-26

Objective Recurrent pregnancy loss (RPL) is a heterogeneous disease which is defined as two or more consecutive fetal losses during early pregnancy. Interleukin-1 receptor antagonist (IL-1Ra) is a anti-inflammatory cytokine, which inhibits IL-1 activity by binding to its receptors. The aim of this study was to investigate the association between RPL and IL-1Ra intron 2 polymorphism (86 bp VNTR) in Iranian women. Materials and methods In this case control study, genetic polymorphism was studied in 140 RPL patients and 140 healthy women as controls. Genomic DNA was extracted from the blood samples and polymorphism analysis was performed using the polymerase chain reaction (PCR) method. Finally, the data obtained were analyzed by statistical software. Results We found an increased frequency of the IL-1Ra 1/1 genotype in the case group compared to the control group. Whereas, the frequency of IL-1Ra genotype 1/2 was higher in control group than in the case group. However, we did not observe an association between IL-1Ra 86 bp VNTR polymorphism in intron 2 and RPL patients (p > 0.05). Conclusion IL-1Ra VNTR polymorphism may not be a genetic factor for RPL. However, investigation of IL-1Ra polymorphism was recommended in other populations and patients with recurrent pregnancy loss.

Variation in the number of nucleoli and incomplete homogenization of 18S ribosomal DNA sequences in leaf cells of the cultivated Oriental ginseng (Panax ginseng Meyer).

PubMed

Chelomina, Galina N; Rozhkovan, Konstantin V; Voronova, Anastasia N; Burundukova, Olga L; Muzarok, Tamara I; Zhuravlev, Yuri N

2016-04-01

Wild ginseng, Panax ginseng Meyer, is an endangered species of medicinal plants. In the present study, we analyzed variations within the ribosomal DNA (rDNA) cluster to gain insight into the genetic diversity of the Oriental ginseng, P. ginseng, at artificial plant cultivation. The roots of wild P. ginseng plants were sampled from a nonprotected natural population of the Russian Far East. The slides were prepared from leaf tissues using the squash technique for cytogenetic analysis. The 18S rDNA sequences were cloned and sequenced. The distribution of nucleotide diversity, recombination events, and interspecific phylogenies for the total 18S rDNA sequence data set was also examined. In mesophyll cells, mononucleolar nuclei were estimated to be dominant (75.7%), while the remaining nuclei contained two to four nucleoli. Among the analyzed 18S rDNA clones, 20% were identical to the 18S rDNA sequence of P. ginseng from Japan, and other clones differed in one to six substitutions. The nucleotide polymorphism was more expressed at the positions 440-640 bp, and distributed in variable regions, expansion segments, and conservative elements of core structure. The phylogenetic analysis confirmed conspecificity of ginseng plants cultivated in different regions, with two fixed mutations between P. ginseng and other species. This study identified the evidences of the intragenomic nucleotide polymorphism in the 18S rDNA sequences of P. ginseng. These data suggest that, in cultivated plants, the observed genome instability may influence the synthesis of biologically active compounds, which are widely used in traditional medicine.

Variation in the number of nucleoli and incomplete homogenization of 18S ribosomal DNA sequences in leaf cells of the cultivated Oriental ginseng (Panax ginseng Meyer)

PubMed Central

Chelomina, Galina N.; Rozhkovan, Konstantin V.; Voronova, Anastasia N.; Burundukova, Olga L.; Muzarok, Tamara I.; Zhuravlev, Yuri N.

2015-01-01

Background Wild ginseng, Panax ginseng Meyer, is an endangered species of medicinal plants. In the present study, we analyzed variations within the ribosomal DNA (rDNA) cluster to gain insight into the genetic diversity of the Oriental ginseng, P. ginseng, at artificial plant cultivation. Methods The roots of wild P. ginseng plants were sampled from a nonprotected natural population of the Russian Far East. The slides were prepared from leaf tissues using the squash technique for cytogenetic analysis. The 18S rDNA sequences were cloned and sequenced. The distribution of nucleotide diversity, recombination events, and interspecific phylogenies for the total 18S rDNA sequence data set was also examined. Results In mesophyll cells, mononucleolar nuclei were estimated to be dominant (75.7%), while the remaining nuclei contained two to four nucleoli. Among the analyzed 18S rDNA clones, 20% were identical to the 18S rDNA sequence of P. ginseng from Japan, and other clones differed in one to six substitutions. The nucleotide polymorphism was more expressed at the positions 440–640 bp, and distributed in variable regions, expansion segments, and conservative elements of core structure. The phylogenetic analysis confirmed conspecificity of ginseng plants cultivated in different regions, with two fixed mutations between P. ginseng and other species. Conclusion This study identified the evidences of the intragenomic nucleotide polymorphism in the 18S rDNA sequences of P. ginseng. These data suggest that, in cultivated plants, the observed genome instability may influence the synthesis of biologically active compounds, which are widely used in traditional medicine. PMID:27158239

Novel quantitative real-time LCR for the sensitive detection of SNP frequencies in pooled DNA: method development, evaluation and application.

PubMed

Psifidi, Androniki; Dovas, Chrysostomos; Banos, Georgios

2011-01-19

Single nucleotide polymorphisms (SNP) have proven to be powerful genetic markers for genetic applications in medicine, life science and agriculture. A variety of methods exist for SNP detection but few can quantify SNP frequencies when the mutated DNA molecules correspond to a small fraction of the wild-type DNA. Furthermore, there is no generally accepted gold standard for SNP quantification, and, in general, currently applied methods give inconsistent results in selected cohorts. In the present study we sought to develop a novel method for accurate detection and quantification of SNP in DNA pooled samples. The development and evaluation of a novel Ligase Chain Reaction (LCR) protocol that uses a DNA-specific fluorescent dye to allow quantitative real-time analysis is described. Different reaction components and thermocycling parameters affecting the efficiency and specificity of LCR were examined. Several protocols, including gap-LCR modifications, were evaluated using plasmid standard and genomic DNA pools. A protocol of choice was identified and applied for the quantification of a polymorphism at codon 136 of the ovine PRNP gene that is associated with susceptibility to a transmissible spongiform encephalopathy in sheep. The real-time LCR protocol developed in the present study showed high sensitivity, accuracy, reproducibility and a wide dynamic range of SNP quantification in different DNA pools. The limits of detection and quantification of SNP frequencies were 0.085% and 0.35%, respectively. The proposed real-time LCR protocol is applicable when sensitive detection and accurate quantification of low copy number mutations in DNA pools is needed. Examples include oncogenes and tumour suppressor genes, infectious diseases, pathogenic bacteria, fungal species, viral mutants, drug resistance resulting from point mutations, and genetically modified organisms in food.

Novel Quantitative Real-Time LCR for the Sensitive Detection of SNP Frequencies in Pooled DNA: Method Development, Evaluation and Application

PubMed Central

Psifidi, Androniki; Dovas, Chrysostomos; Banos, Georgios

2011-01-01

Background Single nucleotide polymorphisms (SNP) have proven to be powerful genetic markers for genetic applications in medicine, life science and agriculture. A variety of methods exist for SNP detection but few can quantify SNP frequencies when the mutated DNA molecules correspond to a small fraction of the wild-type DNA. Furthermore, there is no generally accepted gold standard for SNP quantification, and, in general, currently applied methods give inconsistent results in selected cohorts. In the present study we sought to develop a novel method for accurate detection and quantification of SNP in DNA pooled samples. Methods The development and evaluation of a novel Ligase Chain Reaction (LCR) protocol that uses a DNA-specific fluorescent dye to allow quantitative real-time analysis is described. Different reaction components and thermocycling parameters affecting the efficiency and specificity of LCR were examined. Several protocols, including gap-LCR modifications, were evaluated using plasmid standard and genomic DNA pools. A protocol of choice was identified and applied for the quantification of a polymorphism at codon 136 of the ovine PRNP gene that is associated with susceptibility to a transmissible spongiform encephalopathy in sheep. Conclusions The real-time LCR protocol developed in the present study showed high sensitivity, accuracy, reproducibility and a wide dynamic range of SNP quantification in different DNA pools. The limits of detection and quantification of SNP frequencies were 0.085% and 0.35%, respectively. Significance The proposed real-time LCR protocol is applicable when sensitive detection and accurate quantification of low copy number mutations in DNA pools is needed. Examples include oncogenes and tumour suppressor genes, infectious diseases, pathogenic bacteria, fungal species, viral mutants, drug resistance resulting from point mutations, and genetically modified organisms in food. PMID:21283808

DNA Polymorphism Among American Watermelon Cultivars Based on DNA Methylation

USDA-ARS?s Scientific Manuscript database

American watermelon heirlooms are diverse in their growth habits, fruit qualities and responses to biotic and abiotic stress. Wide ranging DNA marker tools resolved a narrow molecular diversity among these collections. The current research explored additional insights such as extent of diversity a...

An annotated genetic map of loblolly pine based on microsatellite and cDNA markers

Treesearch

Craig S. Echt; Surya Saha; Konstantin V. Krutovsky; Kokulapalan Wimalanathan; John E. Erpelding; Chun Liang; C Dana Nelson

2011-01-01

Previous loblolly pine (Pinus taeda L.) genetic linkage maps have been based on a variety of DNA polymorphisms, such as AFLPs, RAPDs, RFLPs, and ESTPs, but only a few SSRs (simple sequence repeats), also known as simple tandem repeats or microsatellites, have been mapped in P. taeda. The objective of this study was to integrate a large set of SSR markers from a variety...

Molecular and biochemical studies on the effect of gamma rays on lead toxicity in cowpea (Vigna sinensis) plants.

PubMed

Mohamed, Heba Ibrahim

2011-12-01

The effect of lead acetate in the presence or absence of cowpea seeds irradiated with gamma rays on morphological criteria, protein electrophoresis, isozymes, and random amplification of polymorphic DNA-polymerase chain reaction (RAPD-PCR) of leaves was investigated. A highly significant decrease in shoot and root length was observed upon lead acetate exposure (300 and 600 μM). On the other hand, in seeds irradiated with gamma rays (2, 5, and 8 krad), these morphological parameters were increased after lead acetate treatments. Meanwhile, all treatments (lead acetate and gamma rays) caused variations in number, intensity, and/or density of SDS electrophoretic bands of proteins. In addition, electrophoretic studies of esterase, acid phosphatase, peroxidase, polyphenol oxidase, catalase, and superoxide dismutase isozyme activities were increased with increasing the concentrations of lead acetate and gamma ray doses. The variation in DNA profile in response to lead acetate and gamma irradiation treatments was detected by RAPD-PCR technique. The result of RAPD analysis using the five primers indicated the appearance and disappearance of DNA polymorphic bands at all treatments (gamma rays and lead stress). The relatively high concentrations of lead acetate (600 μM) induced more changes in genomic DNA pattern.

C9orf72 Nucleotide Repeat Structures Initiate Molecular Cascades of Disease

PubMed Central

Haeusler, Aaron R.; Donnelly, Christopher J.; Periz, Goran; Simko, Eric A.J.; Shaw, Patrick G.; Kim, Min-Sik; Maragakis, Nicholas J.; Troncoso, Juan C.; Pandey, Akhilesh; Sattler, Rita; Rothstein, Jeffrey D.; Wang, Jiou

2014-01-01

Summary A hexanucleotide repeat expansion (HRE), (GGGGCC)n, in C9orf72 is the most common genetic cause of the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here we identify a molecular mechanism by which structural polymorphism of the HRE leads to ALS/FTD pathology and defects. The HRE forms DNA and RNA G-quadruplexes with distinct structures and promotes RNA•DNA hybrids (R-loops). The structural polymorphism causes a repeat length-dependent accumulation of transcripts aborted in the HRE region. These transcribed repeats bind to ribonucleoproteins in a conformationdependent manner. Specifically, nucleolin (NCL), an essential nucleolar protein, preferentially binds the HRE G-quadruplex, and patient cells show evidence of nucleolar stress. Our results demonstrate that distinct C9orf72 HRE structural polymorphism at both DNA and RNA levels initiates molecular cascades leading to ALS/FTD pathologies, and provide the basis for a mechanistic model for repeat-associated neurodegenerative diseases. PMID:24598541

Detection of linkage disequilibrium between the myotonic dystrophy locus and a new polymorphic DNA marker.

PubMed Central

Harley, H G; Brook, J D; Floyd, J; Rundle, S A; Crow, S; Walsh, K V; Thibault, M C; Harper, P S; Shaw, D J

1991-01-01

We have examined the linkage of two new polymorphic DNA markers (D19S62 and D19S63) and a previously unreported polymorphism with an existing DNA marker (ERCC1) to the myotonic dystrophy (DM) locus. In addition, we have used pulsed-field gel electrophoresis to obtain a fine-structure map of this region. The detection of linkage disequilibrium between DM and one of these markers (D19S63) is the first demonstration of this phenomenon in a heterogeneous DM population. The results suggest that at least 58% of DM patients in the British population, as well as those in a French-Canadian subpopulation, are descended from the same ancestral DM mutation. We discuss the implications of this finding in terms of strategies for cloning the DM gene, for a possible role in modification of risk for prenatal and presymptomatic testing, and we speculate on the origin and number of existing mutations which may result in a DM phenotype. PMID:2063878

Mitochondrial DNA polymorphism in a maternal lineage of Holstein cows.

PubMed Central

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

DNA fingerprinting of jute germplasm by RAPD.

PubMed

Hossain, Mohammad Belayat; Haque, Samiul; Khan, Haseena

2002-07-31

The genotype characteristic of cultivars was investigated, along with varieties of both of the jute species, Corchorus olitorius and Corchorus capsularis, in the germplasm collection at the Bangladesh Jute Research Institute (BJRI). DNA fingerprinting was generated for 9 different varieties and 12 accessions of jute cultivars by using random amplified polymorphic DNA (RAPD). A total of 29 arbitrary oligonucleotide primers were screened. Seven primers gave polymorphism within the varieties, and 6 primers detected polymorphism within the accessions that were tested. A dendrogram was engendered from these data, and this gave a distinct clustering of the cultivated species of jute. Therefore, we generated RAPD markers, which are species-specific. These primers can distinguish between C. olitorius and C. capsularis. From the dendrogram that we generated between the various members of these two species, we found the existing genetic classification that agrees with our molecular marking data. A different dendrogram showed that jute accessions could be clustered into three groups. These data will be invaluable in the conservation and utilization of the genetic pool in the germplasm collection.

Detection of a single nucleotide polymorphism in the human alpha-lactalbumin gene: implications for human milk proteins.

PubMed

Chowanadisai, Winyoo; Kelleher, Shannon L; Nemeth, Jennifer F; Yachetti, Stephen; Kuhlman, Charles F; Jackson, Joan G; Davis, Anne M; Lien, Eric L; Lönnerdal, Bo

2005-05-01

Variability in the protein composition of breast milk has been observed in many women and is believed to be due to natural variation of the human population. Single nucleotide polymorphisms (SNPs) are present throughout the entire human genome, but the impact of this variation on human milk composition and biological activity and infant nutrition and health is unclear. The goals of this study were to characterize a variant of human alpha-lactalbumin observed in milk from a Filipino population by determining the location of the polymorphism in the amino acid and genomic sequences of alpha-lactalbumin. Milk and blood samples were collected from 20 Filipino women, and milk samples were collected from an additional 450 women from nine different countries. alpha-Lactalbumin concentration was measured by high-performance liquid chromatography (HPLC), and milk samples containing the variant form of the protein were identified with both HPLC and mass spectrometry (MS). The molecular weight of the variant form was measured by MS, and the location of the polymorphism was narrowed down by protein reduction, alkylation and trypsin digestion. Genomic DNA was isolated from whole blood, and the polymorphism location and subject genotype were determined by amplifying the entire coding sequence of human alpha-lactalbumin by PCR, followed by DNA sequencing. A variant form of alpha-lactalbumin was observed in HPLC chromatograms, and the difference in molecular weight was determined by MS (wild type=14,070 Da, variant=14,056 Da). Protein reduction and digestion narrowed the polymorphism between the 33rd and 77th amino acid of the protein. The genetic polymorphism was identified as adenine to guanine, which translates to a substitution from isoleucine to valine at amino acid 46. The frequency of variation was higher in milk from China, Japan and Philippines, which suggests that this polymorphism is most prevalent in Asia. There are SNPs in the genome for human milk proteins and their implications for protein bioactivity and infant nutrition need to be considered.

A preliminary report on the genetic variation in pointed gourd (Trichosanthes dioica Roxb.) as assessed by random amplified polymorphic DNA.

PubMed

Adhikari, S; Biswas, A; Bandyopadhyay, T K; Ghosh, P D

2014-06-01

Pointed gourd (Trichosanthes dioica Roxb.) is an economically important cucurbit and is extensively propagated through vegetative means, viz vine and root cuttings. As the accessions are poorly characterized it is important at the beginning of a breeding programme to discriminate among available genotypes to establish the level of genetic diversity. The genetic diversity of 10 pointed gourd races, referred to as accessions was evaluated. DNA profiling was generated using 10 sequence independent RAPD markers. A total of 58 scorable loci were observed out of which 18 (31.03%) loci were considered polymorphic. Genetic diversity parameters [average and effective number of alleles, Shannon's index, percent polymorphism, Nei's gene diversity, polymorphic information content (PIC)] for RAPD along with UPGMA clustering based on Jaccard's coefficient were estimated. The UPGMA dendogram constructed based on RAPD analysis in 10 pointed gourd accessions were found to be grouped in a single cluster and may represent members of one heterotic group. RAPD analysis showed promise as an effective tool in estimating genetic polymorphism in different accessions of pointed gourd.

High-quality and -quantity DNA extraction from frozen archival blood clots for genotyping of single-nucleotide polymorphisms.

PubMed

Bank, Steffen; Nexø, Bjørn Andersen; Andersen, Vibeke; Vogel, Ulla; Andersen, Paal Skytt

2013-06-01

The recovery of biological samples for genetic epidemiological studies can be cumbersome. Blood clots are routinely collected for serological examinations. However, the extraction of DNA from blood clots can be difficult and often results in low yields. The aim was to compare the efficiency of commercial purification kits for extracting DNA from long-term frozen clotted blood. Serum tubes with clotted blood were stored at -20°C for 1 to 2.5 years before DNA extraction. DNA was extracted from 10 blood clot samples using PureGene (Qiagen) with and without glycogen, the QIAamp DNA Micro kit (Qiagen), and the Nucleospin 96 Blood kit (Macherey-Nagel). Furthermore, blood clots from 1055 inflammatory bowel disease patients were purified using the Maxwell 16 Blood purification kit (Promega). The DNA was extracted according to the manufacturers` instructions and real-time PCR and the A(260)/A(280) ratio were used to evaluate the quality of the extracted DNA. The highest DNA yield was obtained by the Maxwell 16 Blood purification kit (Promega) with a median of 4.90 μg (range 0.8-25 μg) pr 300 μL total blood. PureGene with glycogen (Qiagen) had the second highest yield with a median of 0.65 μg (range 0.5-2.6 μg) pr 300 μL total blood. The yield obtained by the different commercial kits varied considerably. Our work demonstrates that high-quality and -quantity DNA can be extracted with the Maxwell 16 Blood purification kit (Promega) from cryopreserved blood clots, even after prolonged storage. The recovered DNA served as a reliable PCR template for single-nucleotide polymorphism assays.

DNA typing in forensic medicine and in criminal investigations: a current survey.

PubMed

Benecke, M

1997-05-01

Since 1985 DNA typing of biological material has become one of the most powerful tools for personal identification in forensic medicine and in criminal investigations [1-6]. Classical DNA "fingerprinting" is increasingly being replaced by polymerase chain reaction (PCR) based technology which detects very short polymorphic stretches of DNA [7-15]. DNA loci which forensic scientists study do not code for proteins, and they are spread over the whole genome [16, 17]. These loci are neutral, and few provide any information about individuals except for their identity. Minute amounts of biological material are sufficient for DNA typing. Many European countries are beginning to establish databases to store DNA profiles of crime scenes and known offenders. A brief overview is given of past and present DNA typing and the establishment of forensic DNA databases in Europe.

DNA typing in forensic medicine and in criminal investigations: a current survey

NASA Astrophysics Data System (ADS)

Benecke, Mark

Since 1985 DNA typing of biological material has become one of the most powerful tools for personal identification in forensic medicine and in criminal investigations [1-6]. Classical DNA "fingerprinting" is increasingly being replaced by polymerase chain reaction (PCR) based technology which detects very short polymorphic stretches of DNA [7-15]. DNA loci which forensic scientists study do not code for proteins, and they are spread over the whole genome [16, 17]. These loci are neutral, and few provide any information about individuals except for their identity. Minute amounts of biological material are sufficient for DNA typing. Many European countries are beginning to establish databases to store DNA profiles of crime scenes and known offenders. A brief overview is given of past and present DNA typing and the establishment of forensic DNA databases in Europe.

Evaluation of the effect of polymorphism on G-quadruplex-ligand interaction by means of spectroscopic and chromatographic techniques

NASA Astrophysics Data System (ADS)

Benito, S.; Ferrer, A.; Benabou, S.; Aviñó, A.; Eritja, R.; Gargallo, R.

2018-05-01

Guanine-rich sequences may fold into highly ordered structures known as G-quadruplexes. Apart from the monomeric G-quadruplex, these sequences may form multimeric structures that are not usually considered when studying interaction with ligands. This work studies the interaction of a ligand, crystal violet, with three guanine-rich DNA sequences with the capacity to form multimeric structures. These sequences correspond to short stretches found near the promoter regions of c-kit and SMARCA4 genes. Instrumental techniques (circular dichroism, molecular fluorescence, size-exclusion chromatography and electrospray ionization mass spectrometry) and multivariate data analysis were used for this purpose. The polymorphism of G-quadruplexes was characterized prior to the interaction studies. The ligand was shown to interact preferentially with the monomeric G-quadruplex; the binding stoichiometry was 1:1 and the binding constant was in the order of 105 M-1 for all three sequences. The results highlight the importance of DNA treatment prior to interaction studies.

Genomic instability in human actinic keratosis and squamous cell carcinoma

PubMed Central

Cabral, Luciana Sanches; Neto, Cyro Festa; Sanches, José A; Ruiz, Itamar R G

2011-01-01

OBJECTIVE: To compare the repetitive DNA patterns of human actinic keratoses and squamous cell carcinomas to determine the genetic alterations that are associated with malignant transformation. INTRODUCTION: Cancer cells are prone to genomic instability, which is often due to DNA polymerase slippage during the replication of repetitive DNA and to mutations in the DNA repair genes. The progression of benign actinic keratoses to malignant squamous cell carcinomas has been proposed by several authors. MATERIAL AND METHODS: Eight actinic keratoses and 24 squamous cell carcinomas (SCC), which were pair-matched to adjacent skin tissues and/or leucocytes, were studied. The presence of microsatellite instability (MSI) and the loss of heterozygosity (LOH) in chromosomes 6 and 9 were investigated using nine PCR primer pairs. Random Amplified Polymorphic DNA patterns were also evaluated using eight primers. RESULTS: MSI was detected in two (D6S251, D9S50) of the eight actinic keratosis patients. Among the 8 patients who had squamous cell carcinoma-I and provided informative results, a single patient exhibited two LOH (D6S251, D9S287) and two instances of MSI (D9S180, D9S280). Two LOH and one example of MSI (D6S251) were detected in three out of the 10 patients with squamous cell carcinoma-II. Among the four patients with squamous cell carcinoma-III, one patient displayed three MSIs (D6S251, D6S252, and D9S180) and another patient exhibited an MSI (D9S280). The altered random amplified polymorphic DNA ranged from 70% actinic keratoses, 76% squamous cell carcinoma-I, and 90% squamous cell carcinoma-II, to 100% squamous cell carcinoma-III. DISCUSSION: The increased levels of alterations in the microsatellites, particularly in D6S251, and the random amplified polymorphic DNA fingerprints were statistically significant in squamous cell carcinomas, compared with actinic keratoses. CONCLUSION: The overall alterations that were observed in the repetitive DNA of actinic keratoses and squamous cell carcinomas indicate the presence of a spectrum of malignant progression. PMID:21655741

Development and application of a 6.5 million feature Affymetrix Genechip® for massively parallel discovery of single position polymorphisms in lettuce (Lactuca spp.)

PubMed Central

2012-01-01

Background High-resolution genetic maps are needed in many crops to help characterize the genetic diversity that determines agriculturally important traits. Hybridization to microarrays to detect single feature polymorphisms is a powerful technique for marker discovery and genotyping because of its highly parallel nature. However, microarrays designed for gene expression analysis rarely provide sufficient gene coverage for optimal detection of nucleotide polymorphisms, which limits utility in species with low rates of polymorphism such as lettuce (Lactuca sativa). Results We developed a 6.5 million feature Affymetrix GeneChip® for efficient polymorphism discovery and genotyping, as well as for analysis of gene expression in lettuce. Probes on the microarray were designed from 26,809 unigenes from cultivated lettuce and an additional 8,819 unigenes from four related species (L. serriola, L. saligna, L. virosa and L. perennis). Where possible, probes were tiled with a 2 bp stagger, alternating on each DNA strand; providing an average of 187 probes covering approximately 600 bp for each of over 35,000 unigenes; resulting in up to 13 fold redundancy in coverage per nucleotide. We developed protocols for hybridization of genomic DNA to the GeneChip® and refined custom algorithms that utilized coverage from multiple, high quality probes to detect single position polymorphisms in 2 bp sliding windows across each unigene. This allowed us to detect greater than 18,000 polymorphisms between the parental lines of our core mapping population, as well as numerous polymorphisms between cultivated lettuce and wild species in the lettuce genepool. Using marker data from our diversity panel comprised of 52 accessions from the five species listed above, we were able to separate accessions by species using both phylogenetic and principal component analyses. Additionally, we estimated the diversity between different types of cultivated lettuce and distinguished morphological types. Conclusion By hybridizing genomic DNA to a custom oligonucleotide array designed for maximum gene coverage, we were able to identify polymorphisms using two approaches for pair-wise comparisons, as well as a highly parallel method that compared all 52 genotypes simultaneously. PMID:22583801

Development and application of a 6.5 million feature Affymetrix Genechip® for massively parallel discovery of single position polymorphisms in lettuce (Lactuca spp.).

PubMed

Stoffel, Kevin; van Leeuwen, Hans; Kozik, Alexander; Caldwell, David; Ashrafi, Hamid; Cui, Xinping; Tan, Xiaoping; Hill, Theresa; Reyes-Chin-Wo, Sebastian; Truco, Maria-Jose; Michelmore, Richard W; Van Deynze, Allen

2012-05-14

High-resolution genetic maps are needed in many crops to help characterize the genetic diversity that determines agriculturally important traits. Hybridization to microarrays to detect single feature polymorphisms is a powerful technique for marker discovery and genotyping because of its highly parallel nature. However, microarrays designed for gene expression analysis rarely provide sufficient gene coverage for optimal detection of nucleotide polymorphisms, which limits utility in species with low rates of polymorphism such as lettuce (Lactuca sativa). We developed a 6.5 million feature Affymetrix GeneChip® for efficient polymorphism discovery and genotyping, as well as for analysis of gene expression in lettuce. Probes on the microarray were designed from 26,809 unigenes from cultivated lettuce and an additional 8,819 unigenes from four related species (L. serriola, L. saligna, L. virosa and L. perennis). Where possible, probes were tiled with a 2 bp stagger, alternating on each DNA strand; providing an average of 187 probes covering approximately 600 bp for each of over 35,000 unigenes; resulting in up to 13 fold redundancy in coverage per nucleotide. We developed protocols for hybridization of genomic DNA to the GeneChip® and refined custom algorithms that utilized coverage from multiple, high quality probes to detect single position polymorphisms in 2 bp sliding windows across each unigene. This allowed us to detect greater than 18,000 polymorphisms between the parental lines of our core mapping population, as well as numerous polymorphisms between cultivated lettuce and wild species in the lettuce genepool. Using marker data from our diversity panel comprised of 52 accessions from the five species listed above, we were able to separate accessions by species using both phylogenetic and principal component analyses. Additionally, we estimated the diversity between different types of cultivated lettuce and distinguished morphological types. By hybridizing genomic DNA to a custom oligonucleotide array designed for maximum gene coverage, we were able to identify polymorphisms using two approaches for pair-wise comparisons, as well as a highly parallel method that compared all 52 genotypes simultaneously.

The 116G > A MSH6 and IVS1-1121C > T PMS2 Genes Polymorphisms Modulate the Risk of the Sporadic Colorectal Cancer Development in Polish Population.

PubMed

Zelga, Piotr; Przybyłowska-Sygut, Karolina; Zelga, Marta; Dziki, Adam; Majsterek, Ireneusz

2018-04-01

Colorectal cancer (CRC) is one of the most common cancers worldwide. DNA mismatch repair (MMR) is an evolutionarily conserved process that corrects mismatches generated during DNA replication. MMR defects were found to be associated with hereditary non-polyposis colorectal cancer (HNPCC) and a subset of sporadic colon cancers. The inheritance of common variations in MMR genes may influences individual susceptibility to the development of colorectal cancer. The purpose of the study was to evaluate the association between gene polymorphisms Glu39Gly (c.116G > A) of MSH6 gene and IVS1-1121C > T of PMS2 gene and sporadic colorectal cancer risk, in a case-control study comprising 200 patients and 200 controls origination from polish population. DNA was isolated from peripheral blood lymphocytes of enrolled patients, and gene polymorphisms were analysed by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) for MSH6 and TaqMan for PMS2. G/A variant of Glu39Gly (c.116G > A) genotype was associated with an increased risk of colorectal cancer (OR 1,65 95%CI:1,01-2,69 p = 0.44). Presence of A allele was also significantly higher in patient with CRC (OR 1,57 95% CI: 1,04-2,38 p = 0.032). Prevalence of this genotype was also markedly higher in females and patients above 60 years in CRC group (OR 2.25 95%CI: 1.22-4.14 p = 0.0098 and OR 2.74 95% CI: 1.27-5.93 p = 0.0097 respectively). None of such correlations was observed for genotype variants of IVS1-1121C > T PMS2. In conclusion, our data suggests thatMSH6 Glu39Gly polymorphism is associated with the risk of developing sporadic colorectal cancer in polish population. Linkage to the female gender, onset above 60 years old and further increase of risk when combined with wild-type allele of PMS2 IVS1-1121C > T polymorphism indicates defective mismatch repair system.

Genetic variation of pronghorn across US Route 89 and State Route 64.

DOT National Transportation Integrated Search

2012-03-01

This study investigated whether highways acted as barriers to gene flow for pronghorn in northern Arizona. DNA : samples from 132 pronghorn were analyzed using eight polymorphic microsatellite loci. Samples represented : animals living on opposite si...

Genetic Variation of Pronghorn across US Highway 89 and State Route 64

DOT National Transportation Integrated Search

2012-03-23

This study investigated whether highways acted as barriers to gene flow for pronghorn in northern Arizona. DNA samples from 132 pronghorn were analyzed using eight polymorphic microsatellite loci. Samples represented animals living on opposite sides ...

Identification of Medically Important Yeasts Using PCR-Based Detection of DNA Sequence Polymorphisms in the Internal Transcribed Spacer 2 Region of the rRNA Genes

PubMed Central

Chen, Y. C.; Eisner, J. D.; Kattar, M. M.; Rassoulian-Barrett, S. L.; LaFe, K.; Yarfitz, S. L.; Limaye, A. P.; Cookson, B. T.

2000-01-01

Identification of medically relevant yeasts can be time-consuming and inaccurate with current methods. We evaluated PCR-based detection of sequence polymorphisms in the internal transcribed spacer 2 (ITS2) region of the rRNA genes as a means of fungal identification. Clinical isolates (401), reference strains (6), and type strains (27), representing 34 species of yeasts were examined. The length of PCR-amplified ITS2 region DNA was determined with single-base precision in less than 30 min by using automated capillary electrophoresis. Unique, species-specific PCR products ranging from 237 to 429 bp were obtained from 92% of the clinical isolates. The remaining 8%, divided into groups with ITS2 regions which differed by ≤2 bp in mean length, all contained species-specific DNA sequences easily distinguishable by restriction enzyme analysis. These data, and the specificity of length polymorphisms for identifying yeasts, were confirmed by DNA sequence analysis of the ITS2 region from 93 isolates. Phenotypic and ITS2-based identification was concordant for 427 of 434 yeast isolates examined using sequence identity of ≥99%. Seven clinical isolates contained ITS2 sequences that did not agree with their phenotypic identification, and ITS2-based phylogenetic analyses indicate the possibility of new or clinically unusual species in the Rhodotorula and Candida genera. This work establishes an initial database, validated with over 400 clinical isolates, of ITS2 length and sequence polymorphisms for 34 species of yeasts. We conclude that size and restriction analysis of PCR-amplified ITS2 region DNA is a rapid and reliable method to identify clinically significant yeasts, including potentially new or emerging pathogenic species. PMID:10834993

XRCC1 Arg194Trp and Arg399Gln polymorphisms and arsenic methylation capacity are associated with urothelial carcinoma

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

Chiang, Chien-I; Huang, Ya-Li; Chen, Wei-Jen

The association between DNA repair gene polymorphisms and bladder cancer has been widely studied. However, few studies have examined the correlation between urothelial carcinoma (UC) and arsenic or its metabolites. The aim of this study was to examine the association between polymorphisms of the DNA repair genes, XRCC1 Arg194Trp, XRCC1 Arg399Gln, XRCC3 Thr241Met, and XPD Lys751Gln, with urinary arsenic profiles and UC. To this end, we conducted a hospital-based case–control study with 324 UC patients and 647 age- and gender-matched non-cancer controls. Genomic DNA was used to examine the genotype of XRCC1 Arg194Trp, XRCC1 Arg399Gln, XRCC3 Thr241Met, and XPD Lys751Glnmore » by PCR-restriction fragment length polymorphism analysis (PCR-RFLP). Urinary arsenic profiles were measured by high performance liquid chromatography (HPLC) linked with hydride generator and atomic absorption spectrometry. The XRCC1 399 Gln/Gln and 194 Arg/Trp and Trp/Trp genotypes were significantly related to UC, and the odds ratio (OR) and 95% confidence interval (95%CI) were 1.68 (1.03–2.75) and 0.66 (0.48–0.90), respectively. Participants with higher total urinary arsenic levels, a higher percentage of inorganic arsenic (InAs%) and a lower percentage of dimethylarsinic acid (DMA%) had a higher OR of UC. Participants carrying XRCC1 risk diplotypes G-C/G-C, A-C/A-C, and A-T/G-T, and who had higher total arsenic levels, higher InAs%, or lower DMA% compared to those with other XRCC1 diplotypes had a higher OR of UC. Our results suggest that the XRCC1 399 Gln/Gln and 194 Arg/Arg DNA repair genes play an important role in poor arsenic methylation capacity, thereby increasing the risk of UC in non-obvious arsenic exposure areas. - Highlights: • The XRCC1 399Gln/Gln genotype was significantly associated with increased OR of UC. • The XRCC1 194 Arg/Trp and Trp/Trp genotype had a significantly decreased OR of UC. • Combined effect of the XRCC1 genotypes and poor arsenic methylation capacity on UC.« less

Identification of the Q969R gain-of-function polymorphism in the gene encoding porcine NLRP3 and its distribution in pigs of Asian and European origin.

PubMed

Tohno, Masanori; Shinkai, Hiroki; Toki, Daisuke; Okumura, Naohiko; Tajima, Kiyoshi; Uenishi, Hirohide

2016-10-01

The nucleotide-binding domain, leucine-rich-containing family, pyrin-domain containing-3 (NLRP3) inflammasome comprises the major components caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and NLRP3. NLRP3 plays important roles in maintaining immune homeostasis mediated by intestinal microorganisms and in the immunostimulatory properties of vaccine adjuvants used to induce an immune response. In the present study, we first cloned a complementary DNA (cDNA) encoding porcine ASC because its genomic sequence was not completely determined. The availability of the ASC cDNA enabled us to reconstitute porcine NLRP3 inflammasomes using an in vitro system that led to the identification of the immune functions of porcine NLRP3 and ASC based on the production of interleukin-1β (IL-1β). Further, we identified six synonymous and six nonsynonymous single-nucleotide polymorphisms (SNPs) in the coding sequence of NLRP3 of six breeds of pigs, including major commercial breeds. Among the nonsynonymous SNPs, the Q969R polymorphism is associated with an increased release of IL-1β compared with other porcine NLRP3 variants, indicating that this polymorphism represents a gain-of-function mutation. This allele was detected in 100 % of the analyzed Chinese Jinhua and Japanese wild boars, suggesting that the allele is maintained in the major commercial native European breeds Landrace, Large White, and Berkshire. These findings represent an important contribution to our knowledge of the diversity of NLRP3 nucleotide sequences among various pig populations. Moreover, efforts to exploit the gain of function induced by the Q969R polymorphism promise to improve pig breeding and husbandry by conferring enhanced resistance to pathogens as well as contributing to vaccine efficacy.

PON1Q192R genetic polymorphism modifies organophosphorous pesticide effects on semen quality and DNA integrity in agricultural workers from southern Mexico

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

Perez-Herrera, N.; Polanco-Minaya, H.; Salazar-Arredondo, E.

Pesticide exposure, including organophosphorous (OP) insecticides, has been associated with poor semen quality, and paraoxonase (PON1), an enzyme involved in OP deactivation, may have a role on their susceptibility, due to PON1 polymorphisms. Our objective was to evaluate the role of PON1Q192R polymorphism on the susceptibility to OP toxicity on semen quality and DNA integrity in agricultural workers. A cross-sectional study was conducted in farmers with Mayan ascendancy from southeastern Mexico chronically exposed to pesticides; mostly OP. Fifty four agricultural workers (18-55 years old) were included, who provided semen and blood samples. Semen quality was evaluated according to WHO, spermmore » DNA damage by in situ-nick translation (NT-positive cells), PON1Q192R polymorphism by real-time PCR and serum PON1 activity by using phenylacetate and paraoxon. Two OP exposure indexes were created: at the month of sampling and during 3 months before sampling, representing the exposure to spermatids-spermatozoa and to cells at one spermatogenic cycle, respectively. PON1 192R and 192Q allele frequencies were 0.54 and 0.46, respectively. Significant associations were found between OP exposure at the month of sampling and NT-positive cells and sperm viability in homozygote 192RR subjects, and dose-effect relationships were observed between OP exposure during 3 months before sampling and sperm quality parameters and NT-positive cells in homozygote 192RR farmers. This suggests that cells at all stages of spermatogenesis are target of OP, and that there exists an interaction between OP exposure and PON1Q192R polymorphism on these effects; farmers featuring the 192RR genotype were more susceptible to develop reproductive toxic effects by OP exposure.« less

SNP discovery through de novo deep sequencing using the next generation of DNA sequencers

USDA-ARS?s Scientific Manuscript database

The production of high volumes of DNA sequence data using new technologies has permitted more efficient identification of single nucleotide polymorphisms in vertebrate genomes. This chapter presented practical methodology for production and analysis of DNA sequence data for SNP discovery....

Characterization of North American Armillaria species: Genetic relationships determined by ribosomal DNA sequences and AFLP markers

Treesearch

M. -S. Kim; N. B. Klopfenstein; J. W. Hanna; G. I. McDonald

2006-01-01

Phylogenetic and genetic relationships among 10 North American Armillaria species were analysed using sequence data from ribosomal DNA (rDNA), including intergenic spacer (IGS-1), internal transcribed spacers with associated 5.8S (ITS + 5.8S), and nuclear large subunit rDNA (nLSU), and amplified fragment length polymorphism (AFLP) markers. Based on rDNA sequence data,...

Use of molecular hybridization to explore genetic relationships. Progress report, July 1, 1975--March 31, 1976. [Primates, mice, Drosophila

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

Atwood, K.C.

Progress is reported on the following research projects: distribution of rDNA in lymphocyte chromosomes of the gibbon; site of 55 DNA in chromosomes of the baboon; satellite associations and rDNA; polymorphisms in rDNA of mouse chromosomes; effect of prephotographing on hybridization; histone and immunoglobulin gene mapping; and rDNA magnification in Drosophila. (HLW)

Polymorphic Homoeolog of Key Gene of RdDM Pathway, ARGONAUTE4_9 class Is Associated with Pre-Harvest Sprouting in Wheat (Triticum aestivum L.)

PubMed Central

Singh, Manjit; Singh, Surinder; Randhawa, Harpinder; Singh, Jaswinder

2013-01-01

Resistance to pre-harvest sprouting (PHS) is an important objective for the genetic improvement of many cereal crops, including wheat. Resistance, or susceptibility, to PHS is mainly influenced by seed dormancy, a complex trait. Reduced seed dormancy is the most important aspect of seed germination on a spike prior to harvesting, but it is influenced by various environmental factors including light, temperature and abiotic stresses. The basic genetic framework of seed dormancy depends on the antagonistic action of abscisic acid (ABA) and gibberellic acid (GA) to promote dormancy and germination. Recent studies have revealed a role for epigenetic changes, predominantly histone modifications, in controlling seed dormancy. To investigate the role of DNA methylation in seed dormancy, we explored the role of ARGONAUTE4_9 class genes in seed development and dormancy in wheat. Our results indicate that the two wheat AGO4_9 class genes i.e. AGO802 and AGO804 map to chromosomes 3S and 1S are preferentially expressed in the embryos of developing seeds. Differential expressions of AGO802-B in the embryos of PHS resistant and susceptible varieties also relates with DNA polymorphism in various wheat varieties due to an insertion of a SINE-like element into this gene. DNA methylation patterns of the embryonic tissue from six PHS resistant and susceptible varieties demonstrate a correlation with this polymorphism. These results suggest a possible role for AGO802-B in seed dormancy and PHS resistance through the modulation of DNA methylation. PMID:24130825

An SNP resource for rice genetics and breeding based on subspecies indica and japonica genome alignments.

PubMed

Feltus, F Alex; Wan, Jun; Schulze, Stefan R; Estill, James C; Jiang, Ning; Paterson, Andrew H

2004-09-01

Dense coverage of the rice genome with polymorphic DNA markers is an invaluable tool for DNA marker-assisted breeding, positional cloning, and a wide range of evolutionary studies. We have aligned drafts of two rice subspecies, indica and japonica, and analyzed levels and patterns of genetic diversity. After filtering multiple copy and low quality sequence, 408,898 candidate DNA polymorphisms (SNPs/INDELs) were discerned between the two subspecies. These filters have the consequence that our data set includes only a subset of the available SNPs (in particular excluding large numbers of SNPs that may occur between repetitive DNA alleles) but increase the likelihood that this subset is useful: Direct sequencing suggests that 79.8% +/- 7.5% of the in silico SNPs are real. The SNP sample in our database is not randomly distributed across the genome. In fact, 566 rice genomic regions had unusually high (328 contigs/48.6 Mb/13.6% of genome) or low (237 contigs/64.7 Mb/18.1% of genome) polymorphism rates. Many SNP-poor regions were substantially longer than most SNP-rich regions, covering up to 4 Mb, and possibly reflecting introgression between the respective gene pools that may have occurred hundreds of years ago. Although 46.2% +/- 8.3% of the SNPs differentiate other pairs of japonica and indica genotypes, SNP rates in rice were not predictive of evolutionary rates for corresponding genes in another grass species, sorghum. The data set is freely available at http://www.plantgenome.uga.edu/snp.

An SNP Resource for Rice Genetics and Breeding Based on Subspecies Indica and Japonica Genome Alignments

PubMed Central

Feltus, F. Alex; Wan, Jun; Schulze, Stefan R.; Estill, James C.; Jiang, Ning; Paterson, Andrew H.

2004-01-01

Dense coverage of the rice genome with polymorphic DNA markers is an invaluable tool for DNA marker-assisted breeding, positional cloning, and a wide range of evolutionary studies. We have aligned drafts of two rice subspecies, indica and japonica, and analyzed levels and patterns of genetic diversity. After filtering multiple copy and low quality sequence, 408,898 candidate DNA polymorphisms (SNPs/INDELs) were discerned between the two subspecies. These filters have the consequence that our data set includes only a subset of the available SNPs (in particular excluding large numbers of SNPs that may occur between repetitive DNA alleles) but increase the likelihood that this subset is useful: Direct sequencing suggests that 79.8% ± 7.5% of the in silico SNPs are real. The SNP sample in our database is not randomly distributed across the genome. In fact, 566 rice genomic regions had unusually high (328 contigs/48.6 Mb/13.6% of genome) or low (237 contigs/64.7 Mb/18.1% of genome) polymorphism rates. Many SNP-poor regions were substantially longer than most SNP-rich regions, covering up to 4 Mb, and possibly reflecting introgression between the respective gene pools that may have occurred hundreds of years ago. Although 46.2% ± 8.3% of the SNPs differentiate other pairs of japonica and indica genotypes, SNP rates in rice were not predictive of evolutionary rates for corresponding genes in another grass species, sorghum. The data set is freely available at http://www.plantgenome.uga.edu/snp. PMID:15342564

Maternal cell traffic bounds for immune modulation: tracking maternal H-2 alleles in spleens of baby mice by DNA fingerprinting.

PubMed

Wan, Wenhan; Shimizu, Shoji; Ikawa, Hiromichi; Sugiyama, Kiyosh; Yamaguchi, Nobuo

2002-10-01

We have previously reported that the immunization of pregnant mice with T-dependent antigens successfully induced suppression of the antigen-specific plaque-forming cell (PFC) response to the relevant antigens in the offspring. This suppression was not caused by the administered antigens, the antibodies produced by the pregnant mother, or lactational transfer, but was dependent on the presence of the intact maternal T cells. It was major histocompatibility complex (MHC)-restricted manner tolerance, which continued for at least one-sixth of the murine life. Traditionally, the placenta acts as a natural barrier, not allowing the cells to pass through. However, the results presented strongly suggested that maternal T cells pass through the placenta and subsequently induce tolerance. In this present study, we attempted to substantiate the presence of maternal cells in the fetal circulation through the use of molecular techniques. We found that a highly polymorphic microsatellite sequence within the class II Eb gene of the H-2 complex is useful for the molecular detection of various H-2 alleles. DNA polymorphic analysis was used for tracking maternal H-2 alleles in the spleens of baby mice. The main procedure involved polymerase chain reaction amplification and restriction fragment length polymorphism analysis of the DNA sequence encompassing the H-2-specific microsatellite from the genomic DNA of baby mice. The results indicated that maternal T cells of immunized pregnant mice cross the placenta into the fetus, eventually inducing antigen-specific immunological tolerance in the offspring.

The DNA Methyltransferase 3B -149 Genetic Polymorphism Modulates Lung Cancer Risk from Smoking

PubMed Central

Lai, Chung Yu; Huang, Chia Chen; Tsai, Chin Hung; Wang, Jiun Yao; Kerr, Chih Ling; Chen, Yi Yu; Cai, Yan Wei; Wong, Ruey Hong

2017-01-01

Background: Smoking can cause increase of DNA methylation and hypermethylation of tumor suppressor genes, this possible contributing to subsequent lung cancer development. DNA methyltransferase 3B (DNMT3B) is crucial in regulation of DNA methylation and it has been proposed that green tea might lower cancer risk through inhibiting its activity. Here, we designed a case-control study to investigate whether the DNMT3B -149 genetic polymorphism could modulate lung cancer risk due to smoking. Possible interactions of smoking and green tea consumption with this DNMT3B genetic polymorphism were also assessed. Materials and Methods: A total of 190 lung cancer patients and 380 healthy controls were recruited. Questionnaires were administered to obtain data on sociodemographic and lifestyle variables, as well as family history of lung cancer. Genotypes for DNMT3B -149 were identified by polymerase chain reaction. Results: Smoking, green tea consumption, exposure to cooking fumes, family history of lung cancer, and the DNMT3B -149 genotype (odds ratio (OR)=2.65; 95% confidence interval (CI) 1.15-6.10) were all significantly associated with the development of lung cancer. Smokers carrying the DNMT3B -149 TT genotype were at elevated risk compared to non-smokers carrying DNMT3B -149 (OR=7.69; 95% CI 2.55-23.14). Interaction of smoking with DNMT3B -149 genotypes was significant regarding lung cancer risk. However, interaction between green tea drinking and DNMT3B -149 genotypes was not. Conclusions: The DNMT3B -149 TT genotype might increase the smoking-associated lung cancer risk. PMID:29072397

T-cell receptor V sub. alpha. and C sub. alpha. alleles associated with multiple sclerosis and myasthenia gravis

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

Oksenberg, J.R.; Cavalli-Sforza, L.L.; Steinman, L.

1989-02-01

Polymorphic markers in genes encoding the {alpha} chain of the human T-cell receptor (TcR) have been detected by Southern blot analysis in Pss I digests. Polymorphic bands were observed at 6.3 and 2.0 kilobases (kb) with frequencies of 0.30 and 0.44, respectively, in the general population. Using the polymerase chain reaction (PCR) method, the authors amplified selected sequences derived from the full-length TcR {alpha} cDNA probe. These PcR products were used as specific probes to demonstrate that the 6.3-kb polymorphic fragment hybridizes to the variable (V)-region probe and the 2.0-kb fragment hybridizes to the constant (C)-region probe. Segregation of themore » polymorphic bands was analyzed in family studies. To look for associations between these markers and autoimmune diseases, the authors have studied the restriction fragment length polymorphism distribution of the Pss I markers in patients with multiple sclerosis, myasthenia gravis, and Graves disease. Significant differences in the frequency of the polymorphic V{sub {alpha}} and C{sub {alpha}} markers were identified between patients and healthy individuals.« less

Reduced rDNA Copy Number Does Not Affect “Competitive” Chromosome Pairing in XYY Males of Drosophila melanogaster

PubMed Central

Maggert, Keith A.

2014-01-01

The ribosomal DNA (rDNA) arrays are causal agents in X-Y chromosome pairing in meiosis I of Drosophila males. Despite broad variation in X-linked and Y-linked rDNA copy number, polymorphisms in regulatory/spacer sequences between rRNA genes, and variance in copy number of interrupting R1 and R2 retrotransposable elements, there is little evidence that different rDNA arrays affect pairing efficacy. I investigated whether induced rDNA copy number polymorphisms affect chromosome pairing in a “competitive” situation in which complex pairing configurations were possible using males with XYY constitution. Using a common normal X chromosome, one of two different full-length Y chromosomes, and a third chromosome from a series of otherwise-isogenic rDNA deletions, I detected no differences in X-Y or Y-Y pairing or chromosome segregation frequencies that could not be attributed to random variation alone. This work was performed in the context of an undergraduate teaching program at Texas A&M University, and I discuss the pedagogical utility of this and other such experiments. PMID:24449686

Cloning and characterization of transferrin cDNA and rapid detection of transferrin gene polymorphism in rainbow trout (Oncorhynchus mykiss).

PubMed

Tange, N; Jong-Young, L; Mikawa, N; Hirono, I; Aoki, T

1997-12-01

A cDNA clone of rainbow trout (Oncorhynchus mykiss) transferrin was obtained from a liver cDNA library. The 2537-bp cDNA sequence contained an open reading frame encoding 691 amino acids and the 5' and 3' noncoding regions. The amino acid sequences at the iron-binding sites and the two N-linked glycosylation sites, and the cysteine residues were consistent with known, conserved vertebrate transferrin cDNA sequences. Single N-linked glycosylation sites existed on the N- and C-lobe. The deduced amino acid sequence of the rainbow trout transferrin cDNA had 92.9% identities with transferrin of coho salmon (Oncorhynchus kisutch); 85%, Atlantic salmon (Salmo salar); 67.3%, medaka (Oryzias latipes); 61.3% Atlantic cod (Gadus morhua); and 59.7%, Japanese flounder (Paralichthys olivaceus). The long and accurate polymerase chain reaction (LA-PCR) was used to amplify approximately 6.5 kb of the transferrin gene from rainbow trout genomic DNA. Restriction fragment length polymorphisms (RFLPs) of the LA-PCR products revealed three digestion patterns in 22 samples.

Cloning of polymorphisms (COP): enrichment of polymorphic sequences from complex genomes

PubMed Central

Li, Jingfeng; Wang, Fuli; Zabarovska, Veronika; Wahlestedt, Claes; Zabarovsky, Eugene R.

2000-01-01

Here we describe a new procedure (cloning of polymorphisms, COP) for enrichment of single nucleotide polymorphisms (SNPs) that represent restriction fragment length polymorphisms (RFLPs). COP would be applicable to the isolation of SNPs from particular regions of the genome, e.g. CpG islands, chromosomal bands, YACs or PAC contigs. A combination of digestion with restriction enzymes, treatment with uracil-DNA glycosylase and mung bean nuclease, PCR amplification and purification with streptavidin magnetic beads was used to isolate polymorphic sequences from the genomes of two human samples. After only two cycles of enrichment, 80% of the isolated clones were found to contain RFLPs. A simple method for the PCR detection of these polymorphisms was also developed. PMID:10606669

Detection of single-nucleotide polymorphisms using an ON-OFF switching of regenerated biosensor based on a locked nucleic acid-integrated and toehold-mediated strand displacement reaction.

PubMed

Gao, Zhong Feng; Ling, Yu; Lu, Lu; Chen, Ning Yu; Luo, Hong Qun; Li, Nian Bing

2014-03-04

Although various strategies have been reported for single-nucleotide polymorphisms (SNPs) detection, development of a time-saving, specific, and regenerated electrochemical sensing platform still remains a realistic goal. In this study, an ON-OFF switching of a regenerated biosensor based on a locked nucleic acid (LNA)-integrated and toehold-mediated strand displacement reaction technique is constructed for detection of SNPs. The LNA-integrated and methylene blue-labeled capture probe with an external toehold is designed to switch on the sensing system. The mutant-type DNA probe completes complementary with the capture probe to trigger the strand displacement reaction, which switches off the sensing system. However, when the single-base mismatched wild-type DNA probe is presented, the strand displacement reaction cannot be achieved; therefore, the sensing system still keeps the ON state. This DNA sensor is stable over five reuses. We further testify that the LNA-integrated sequence has better recognition ability for SNPs detection compared to the DNA-integrated sequence. Moreover, this DNA senor exhibits a remarkable discrimination capability of SNPs among abundant wild-type targets and 6000-fold (m/m) excess of genomic DNA. In addition, it is selective enough in complex and contaminant-ridden samples, such as human urine, soil, saliva, and beer. Overall, these results demonstrate that this reliable DNA sensor is easy to be fabricated, simple to operate, and stable enough to be readily regenerated.

Analysis of DNA Cytosine Methylation Patterns Using Methylation-Sensitive Amplification Polymorphism (MSAP).

PubMed

Guevara, María Ángeles; de María, Nuria; Sáez-Laguna, Enrique; Vélez, María Dolores; Cervera, María Teresa; Cabezas, José Antonio

2017-01-01

Different molecular techniques have been developed to study either the global level of methylated cytosines or methylation at specific gene sequences. One of them is the methylation-sensitive amplified polymorphism technique (MSAP) which is a modification of amplified fragment length polymorphism (AFLP). It has been used to study methylation of anonymous CCGG sequences in different fungi, plants, and animal species. The main variation of this technique resides on the use of isoschizomers with different methylation sensitivity (such as HpaII and MspI) as a frequent-cutter restriction enzyme. For each sample, MSAP analysis is performed using both EcoRI/HpaII- and EcoRI/MspI-digested samples. A comparative analysis between EcoRI/HpaII and EcoRI/MspI fragment patterns allows the identification of two types of polymorphisms: (1) methylation-insensitive polymorphisms that show common EcoRI/HpaII and EcoRI/MspI patterns but are detected as polymorphic amplified fragments among samples and (2) methylation-sensitive polymorphisms which are associated with the amplified fragments that differ in their presence or absence or in their intensity between EcoRI/HpaII and EcoRI/MspI patterns. This chapter describes a detailed protocol of this technique and discusses the modifications that can be applied to adjust the technology to different species of interest.

MTHFR polymorphisms in Puerto Rican children with isolated congenital heart disease and their mothers

PubMed Central

García-Fragoso, Lourdes; García-García, Inés; Leavitt, Gloria; Renta, Jessicca; Ayala, Miguel A.; Cadilla, Carmen L.

2010-01-01

Congenital heart defects (CHD) are among the most common birth defects. There is evidence suggesting that polymorphisms in folate metabolism could alter susceptibility to CHD. The MTHFR 677TT genotype has been associated with the development of structural congenital heart malformations. The objective of this study was to identify common polymorphisms in the MTHFR gene in children with isolated CHD and their mothers. The DNA analysis for the C677T and A1298C mutations was performed. The study group included 27 mothers, 27 children with CHD, and 220 controls. The prevalence of the TT polymorphism was higher in mothers (22%) than in controls (10%). Compound heterozygosity for both polymorphisms was 3.7 times more common in children with CHD than in the newborn controls. Mothers of children with CHD were more likely to be compound heterozygotes. The higher prevalence of C677T polymorphisms in mothers of children with CHD and of compound heterozygosity for both polymorphisms suggests the possible role of folic acid in the prevention of CHD. Due to the relation of this enzyme to folate metabolism, current folate recommendations for women in childbearing age in Puerto Rico to reduce neural tube defects may need to be extended to the prevention of CHD. PMID:20657745

MTHFR polymorphisms in Puerto Rican children with isolated congenital heart disease and their mothers.

PubMed

García-Fragoso, Lourdes; García-García, Inés; Leavitt, Gloria; Renta, Jessicca; Ayala, Miguel A; Cadilla, Carmen L

2010-03-01

Congenital heart defects (CHD) are among the most common birth defects. There is evidence suggesting that polymorphisms in folate metabolism could alter susceptibility to CHD. The MTHFR 677TT genotype has been associated with the development of structural congenital heart malformations. The objective of this study was to identify common polymorphisms in the MTHFR gene in children with isolated CHD and their mothers. The DNA analysis for the C677T and A1298C mutations was performed. The study group included 27 mothers, 27 children with CHD, and 220 controls. The prevalence of the TT polymorphism was higher in mothers (22%) than in controls (10%). Compound heterozygosity for both polymorphisms was 3.7 times more common in children with CHD than in the newborn controls. Mothers of children with CHD were more likely to be compound heterozygotes. The higher prevalence of C677T polymorphisms in mothers of children with CHD and of compound heterozygosity for both polymorphisms suggests the possible role of folic acid in the prevention of CHD. Due to the relation of this enzyme to folate metabolism, current folate recommendations for women in childbearing age in Puerto Rico to reduce neural tube defects may need to be extended to the prevention of CHD.

Blood grouping based on PCR methods and agarose gel electrophoresis.

PubMed

Sell, Ana Maria; Visentainer, Jeane Eliete Laguila

2015-01-01

The study of erythrocyte antigens continues to be an intense field of research, particularly after the development of molecular testing methods. More than 300 specificities have been described by the International Society for Blood Transfusion as belonging to 33 blood group systems. The polymerase chain reaction (PCR) is a central tool for red blood cells (RBC) genotyping. PCR and agarose gel electrophoresis are low cost, easy, and versatile in vitro methods for amplifying defined target DNA (RBC polymorphic region). Multiplex-PCR, AS-PCR (Specific Allele Polymerase Chain Reaction), and RFLP-PCR (Restriction Fragment Length Polymorphism-Polymerase Chain Reaction) techniques are usually to identify RBC polymorphisms. Furthermore, it is an easy methodology to implement. This chapter describes the PCR methodology and agarose gel electrophoresis to identify the polymorphisms of the Kell, Duffy, Kidd, and MNS blood group systems.

Genetic structure of Pilosocereus gounellei (Cactaceae) as revealed by AFLP marker to guide proposals for improvement and restoration of degraded areas in Caatinga biome.

PubMed

Monteiro, E R; Strioto, D K; Meirelles, A C S; Mangolin, C A; Machado, M F P S

2015-12-15

Amplified fragment length polymorphism (AFLP) analysis was used to evaluate DNA polymorphism in Pilosocereus gounellei with the aim of differentiating samples grown in different Brazilian semiarid regions. Seven primer pairs were used to amplify 703 AFLP markers, of which 700 (99.21%) markers were polymorphic. The percentage of polymorphic markers ranged from 95.3% for the primer combination E-AAG/M-CTT to 100% for E-ACC/M-CAT, E-ACC/M-CAA, E-AGC/M-CAG, E-ACT/M-CTA, and E-AGG/M-CTG. The largest number of informative markers (126) was detected using the primer combination E-AAC/M-CTA. Polymorphism of the amplified DNA fragments ranged from 72.55% (in sample from Piauí State) to 82.79% (in samples from Rio Grande Norte State), with an average of 75.39%. Despite the high genetic diversity of AFLP markers in xiquexique, analysis using the STRUCTURE software identified relatively homogeneous clusters of xiquexique from the same location, indicating a differentiation at the molecular level, among the plant samples from different regions of the Caatinga biome. The AFLP methodology identified genetically homogeneous and contrasting plants, as well as plants from different regions with common DNA markers. Seeds from such plants can be used for further propagation of plants for establishment of biodiversity conservation units and restoration of degraded areas of the Caatinga biome.

Genetic polymorphisms variants in interleukin-6 and interleukin-1beta patients with obstructive sleep apnea syndrome in East Northern Turkey.

PubMed

Gok, Ilhami; Huseyinoglu, Nergiz; Ilhan, Dogan

2015-08-01

To investigate the relationship of IL-1β and IL-6 cytokine gene polymorphisms with obstructive sleep apnea syndrome (OSAS) in 61 patients admitted to the neurology clinic in Kafkas University Hospital with insomnia problem who were diagnosed with OSAS in sleeping labs, and 80 healthy subjects not associated with the syndrome. METHODS :Blood samples were taken to isolate DNA from patients diagnosed with OSAS based on polysomnography results and healthy controls. DNA amplification of the genes was performed with PCR. Amplification products were cut with the restriction enzymes in order to determine IL-1 gene (TaqI) and IL-6 gene (Lwel) polymorphisms. The cut DNA fragments were carried out in agarose gel electrophoresis, and RFLP analysis was performed by utilizing the images with gel imaging system. PCR products were sequenced with an Applied Biosystems Automated Sequencer. Polymorphic changes were observed for IL-1β gene in 26 of 62 patients (41.9%), and 16 of the 80 (25.8%) in the control group. The incidence of polymorphic changes in IL-6 gene was in seen in seven (of the 62 patients) (11.3%), and in the 16 (20%) controls. The findings on the genomic level in OSAS may provide an important contribution to diagnosis of obstructive sleep apnea syndrome in clinical practice, as well as it helps to obtain the results easily about environmental and genetic interaction of OSAS patients. Copyright© by the Medical Assotiation of Zenica-Doboj Canton.

Applicability of SCAR markers to food genomics: olive oil traceability.

PubMed

Pafundo, Simona; Agrimonti, Caterina; Maestri, Elena; Marmiroli, Nelson

2007-07-25

DNA analysis with molecular markers has opened a shortcut toward a genomic comprehension of complex organisms. The availability of micro-DNA extraction methods, coupled with selective amplification of the smallest extracted fragments with molecular markers, could equally bring a breakthrough in food genomics: the identification of original components in food. Amplified fragment length polymorphisms (AFLPs) have been instrumental in plant genomics because they may allow rapid and reliable analysis of multiple and potentially polymorphic sites. Nevertheless, their direct application to the analysis of DNA extracted from food matrixes is complicated by the low quality of DNA extracted: its high degradation and the presence of inhibitors of enzymatic reactions. The conversion of an AFLP fragment to a robust and specific single-locus PCR-based marker, therefore, could extend the use of molecular markers to large-scale analysis of complex agro-food matrixes. In the present study is reported the development of sequence characterized amplified regions (SCARs) starting from AFLP profiles of monovarietal olive oils analyzed on agarose gel; one of these was used to identify differences among 56 olive cultivars. All the developed markers were purposefully amplified in olive oils to apply them to olive oil traceability.

Pharmacogenetic Study in Rectal Cancer Patients Treated With Preoperative Chemoradiotherapy: Polymorphisms in Thymidylate Synthase, Epidermal Growth Factor Receptor, GSTP1, and DNA Repair Genes

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

Paez, David, E-mail: dpaez@santpau.cat; Salazar, Juliana; Pare, Laia

Purpose: Several studies have been performed to evaluate the usefulness of neoadjuvant treatment using oxaliplatin and fluoropyrimidines for locally advanced rectal cancer. However, preoperative biomarkers of outcome are lacking. We studied the polymorphisms in thymidylate synthase, epidermal growth factor receptor, glutathione S-transferase pi 1 (GSTP1), and several DNA repair genes to evaluate their usefulness as pharmacogenetic markers in a cohort of 128 rectal cancer patients treated with preoperative chemoradiotherapy. Methods and Materials: Blood samples were obtained from 128 patients with Stage II-III rectal cancer. DNA was extracted from the peripheral blood nucleated cells, and the genotypes were analyzed by polymerasemore » chain reaction amplification and automated sequencing techniques or using a 48.48 dynamic array on the BioMark system. The germline polymorphisms studied were thymidylate synthase, (VNTR/5 Prime UTR, 2R G>C single nucleotide polymorphism [SNP], 3R G>C SNP), epidermal growth factor receptor (Arg497Lys), GSTP1 (Ile105val), excision repair cross-complementing 1 (Asn118Asn, 8092C>A, 19716G>C), X-ray repair cross-complementing group 1 (XRCC1) (Arg194Trp, Arg280His, Arg399Gln), and xeroderma pigmentosum group D (Lys751Gln). The pathologic response, pathologic regression, progression-free survival, and overall survival were evaluated according to each genotype. Results: The Asterisk-Operator 3/ Asterisk-Operator 3 thymidylate synthase genotype was associated with a greater response rate (pathologic complete remission and microfoci residual tumor, 59% in Asterisk-Operator 3/ Asterisk-Operator 3 vs. 35% in Asterisk-Operator 2/ Asterisk-Operator 2 and Asterisk-Operator 2/ Asterisk-Operator 3; p = .013). For the thymidylate synthase genotype, the median progression-free survival was 103 months for the Asterisk-Operator 3/ Asterisk-Operator 3 patients and 84 months for the Asterisk-Operator 2/ Asterisk-Operator 2 and Asterisk-Operator 2/ Asterisk-Operator 3 patients (p = .039). For XRCC1 Arg399Gln SNP, the median progression-free survival was 101 months for the G/G, 78 months for the G/A, and 31 months for the A/A patients (p = .048). Conclusions: The thymidylate synthase genotype and XRCC1 Arg399Gln polymorphism might help to identify Stage II-III rectal cancer patients with a better outcome after preoperative concomitant chemoradiotherapy.« less

Dopamine transporter gene polymorphism in children with ADHD: A pilot study in Indonesian samples.

PubMed

Wiguna, Tjhin; Ismail, Raden Irawati; Winarsih, Noorhana Setyawati; Kaligis, Fransiska; Hapsari, Anggia; Budiyanti, Lina; Sekartini, Rini; Rahayu, Susan; Guerrero, Anthony P S

2017-10-01

Several studies showed that DAT1 polymorphism closed related with ADHD although the results were not consistently found. Studies in China, South Korea, Japan revealed that 10-repeat allele gave a risk for ADHD. Based on that understanding, this study tried to identify whether the similar polymorphism of DAT1 was also apparent in Indonesian children with ADHD. This was a case - control study. Case was 50 Indonesian origin children with ADHD and without any other mental disorders and metal retardation. Control is Indonesian origin children without ADHD, other mental disorders and mental retardation. ADHD diagnosis was taken after doing the psychiatric interview and observation based on the DSM-IV TR diagnostic criteria for ADHD at the Child and Adolescent Psychiatry Out-patient Clinic, Dr. Cipto Mangunkusumo National Referral Hospital - Faculty of Medicine Universitas Indonesia. DNA isolation, DNA purity and concentration were measured. PCR was done by using a primer based on Homo sapiens solute carrier family 6 (neurotransmitter transporter), member 3 (SLC6A3), RefSeq Gene on chromosome 5 with accession number NG_015885.1. To identify the serial of repeated allele, we used the sequencing technique. There were 47 children with ADHD and 48 children without ADHD that involved in the final analysis. The mean of age amongst ADHD group was 9.18 (2.42) and 8.10 (2.46) years old in non-ADHD group. The 10-repeated allele of DAT1 was the highest proportion in both. This finding was apparently similar with other studies on DAT1 polymorphism across Asian. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of EST Intron-Targeting SNP Markers for Panax ginseng and Their Application to Cultivar Authentication

PubMed Central

Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun

2016-01-01

Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to “Gopoong” and “K-1” were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information. PMID:27271615

[Study on association of CTLA4 gene polymorphism with Grave's disease in Guangxi Zhuang nationality population].

PubMed

Liang, Xing-huan; Qin, Ying-fen; Ma, Yan; Xie, Xin-rong; Xie, Kai-qing; Luo, Zuo-jie

2006-06-01

To investigate the relationship between the polymorphic (AT)n repeats in 3ountranslated region of exon 4 of CTLA4 gene [CTLA4(AT)n] and Graveso disease (GD) in Zhuang nationality population of Guangxi province. The studied groups comprised 48 patients with GD and 44 normal controls. Amplification of target DNA was carried out by polymerase chain reaction (PCR). The amplified products were run by 8% polyacrylamide gel electrophoresis, and then followed by 0.1% silver staining. Some of amplified products were sequenced directly. Nineteen alleles of CTLA4 gene microsatellite polymorphism were found in Guangxi Zhuang nationality individuals. The 106 bp long allele was apparently increased in patients with GD of Zhuang nationality but not in healthy controls (P< 0.05). CTLA4 gene microsatellite polymorphism is strongly associated with Graveso disease in Zhuang nationality population of Guangxi province. CTLA4(AT)n 106 bp may be the susceptible gene in GD patients of Zhuang nationality in Guangxi; 19 alleles of CTLA4 gene microsatellite polymorphism were found in Guangxi Zhuang nationality individuals.

The relationship between changes in functional cardiac parameters following anthracycline therapy and carbonyl reductase 3 and glutathione S transferase Pi polymorphisms.

PubMed

Volkan-Salanci, Bilge; Aksoy, Hakan; Kiratli, Pınar Özgen; Tülümen, Erol; Güler, Nilüfer; Öksüzoglu, Berna; Tokgözoğlu, Lale; Erbaş, Belkıs; Alikaşifoğlu, Mehmet

2012-10-01

The aim of this prospective clinical study is to evaluate the relationship between changes in functional cardiac parameters following anthracycline therapy and carbonyl reductase 3 (CBR3p.V244M) and glutathione S transferase Pi (GSTP1p.I105V) polymorphisms. Seventy patients with normal cardiac function and no history of cardiac disease scheduled to undergo anthracycline chemotherapy were included in the study. The patients' cardiac function was evaluated by gated blood pool scintigraphy and echocardiography before and after chemotherapy, as well as 1 year following therapy. Gene polymorphisms were genotyped in 70 patients using TaqMan probes, validated by DNA sequencing. A deteriorating trend was observed in both systolic and diastolic parameters from GG to AA in CBR3p.V244M polymorphism. Patients with G-allele carriers of GSTP1p.I105V polymorphism were common (60%), with significantly decreased PFR compared to patiens with AA genotype. Variants of CBR3 and GSTP1 enzymes may be associated with changes in short-term functional cardiac parameters.

The CYP3A4 *1B polymorphism and prostate cancer susceptibility in a Portuguese population.

PubMed

Nogal, Ana; Coelho, Ana; Catarino, Raquel; Morais, António; Lobo, Francisco; Medeiros, Rui

2007-09-01

Testosterone exposure has been implicated in prostate carcinogenesis, and genes that alter its metabolism, such as CYP3A4, have been associated with prostate cancer susceptibility. The aim of our study was to assess the relationship between the CYP3A4 *1B polymorphism and its possible role in the development of prostate cancer. DNA samples obtained from the peripheral blood cells of 414 individuals diagnosed with prostate cancer and 337 healthy male donors were used in this case-control study. The CYP3A4*1B polymorphism was analyzed by polymerase chain reaction-restriction fragment length polymorphism methodology. We found no statistically significant differences in the distribution of the CYP3A4*1B genotypes between cases and controls (P = 0.470; odds ratio = 1.191; 95% confidence interval=0.740-1.918), as well as after the stratification of our analysis, according to important clinicopathologic parameters of prostate cancer. Our results suggest that the CYP3A4*1B polymorphism is not associated with prostate cancer risk within the Portuguese population.

Association between MTHFR variant and diabetic neuropathy.

PubMed

Kakavand Hamidi, Armita; Radfar, Mania; Amoli, Mahsa M

2018-02-01

Methylene-tetrahydrofolate reductase (MTHFR) gene variant may play an important role in the pathophysiology of diabetes and its complications due to its influence on plasma homocysteine levels and also its effect on scavenging peroxynitrite radicals. Diabetic peripheral neuropathy (DPN) is one of the most common diabetic chronic complications. The aim of this study was to investigate the relationship between diabetic neuropathy and MTHFR gene C677T and 1298A ⁄C polymorphisms. Patients with type 2 diabetes N=248 were enrolled in the study, consisting of patients with neuropathy (N=141) and patients without neuropathy (N=107). MTHFR C677T polymorphism was analyzed using polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) of genomic DNA for genotyping of samples. 1298A/C polymorphism was evaluated using ARMS-PCR. There was a significant difference in MTHFR polymorphism between the groups with and without neuropathy. Our results suggest that MTHFR 677 variant confer risk for diabetic neuropathy among Iranian patients with type 2 diabetes. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Association of CYP1A1 and CYP1B1 polymorphisms with bone mineral density variations in postmenopausal Mexican-Mestizo women.

PubMed

Chávez, Bertha; Vilchis, Felipe; Rojano-Mejía, David; Coral Vázquez, Ramón Mauricio; Aguirre-García, María Del Carmen; Canto, Patricia

2017-08-01

Herein, we investigated potential associations between polymorphisms of genes related to estrogen metabolism and bone mineral density (BMD) in postmenopausal women. This was a cross-sectional study, in which two hundred and ninety postmenopausal Mexican-Mestizo women were studied. The BMD of the lumbar spine (LS), total hip (TH), and femoral neck (FN) was measured. The distribution of the genetic polymorphisms, including rs1799814 and rs1048943 at CYP1A1 as well as rs1056836 at CYP1B1, were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), single-stranded conformational polymorphism (SSCP), and DNA sequencing. Deviations from Hardy-Weinberg equilibrium (HWE) were tested, and linkage disequilibrium (LD) was calculated by direct correlation (r 2 ). Moreover, haplotype analysis was performed. All polymorphisms were in HWE. The genotype and allele distributions of the three single nucleotide polymorphisms (SNPs) studied showed no significant differences. However, statistical significance was reached when constructing haplotypes. The CG haplotype in CYP1A1 was associated with variations in LS and FN BMD after adjustment for covariates (p = 0.021 and 0.045, respectively), but the association with TH BMD was not significant. These results suggested that the CG haplotype in CYP1A1 may play an important role in the mechanism of osteoporosis and may be useful as a genetic marker.

Polymorphism in the PER3 promoter associates with diurnal preference and delayed sleep phase disorder.

PubMed

Archer, Simon N; Carpen, Jayshan D; Gibson, Mark; Lim, Gim Hui; Johnston, Jonathan D; Skene, Debra J; von Schantz, Malcolm

2010-05-01

To screen the PER3 promoter for polymorphisms and investigate the phenotypic associations of these polymorphisms with diurnal preference, delayed sleep phase disorder/syndrome (DSPD/DSPS), and their effects on reporter gene expression. Interspecific comparison was used to define the approximate extent of the PER3 promoter as the region between the transcriptional start site and nucleotide position -874. This region was screened in DNA pools using PCR and direct sequencing, which was also used to screen DNA from individual participants. The different promoter alleles were cloned into a luciferase expression vector and a deletion library created. Promoter activation was measured by chemiluminescence. N/A. DNA samples were obtained from volunteers with defined diurnal preference (3 x 80, selected from a pool of 1,590), and DSPD patients (n=23). N/A. We verified three single nucleotide polymorphisms (G -320T, C -319A, G -294A), and found a novel variable number tandem repeat (VNTR) polymorphism (-318 1/2 VNTR). The -320T and -319A alleles occurred more frequently in DSPD compared to morning (P = 0.042 for each) or evening types (P = 0.006 and 0.033). The allele combination TA2G was more prevalent in DSPD compared to morning (P 0.033) or evening types (P = 0.002). Luciferase expression driven by the TA2G combination was greater than for the more common GC2A (P < 0.05) and the rarer TA1G (P < 0.001) combinations. Deletion reporter constructs identified two enhancer regions (-703 to -605, and -283 to -80). Polymorphisms in the PER3 promoter could affect its expression, leading to potential differences in the observed functions of PER3.

Leishmania major: genetic heterogeneity of Iranian isolates by single-strand conformation polymorphism and sequence analysis of ribosomal DNA internal transcribed spacer.

PubMed

Tashakori, Mahnaz; Mahnaz, Tashakori; Kuhls, Katrin; Katrin, Kuhls; Al-Jawabreh, Amer; Amer, Al-Jawabreh; Mauricio, Isabel L; Isabel, Mauricio; Schönian, Gabriele; Gabriele, Schönian; Farajnia, Safar; Safar, Farajnia; Alimohammadian, Mohammad Hossein; Hossein, Alimohammadian Mohammad

2006-04-01

Protozoan parasites of Leishmania major are the causative agents of cutaneous leishmaniasis in different parts of Iran. We applied PCR-based methods to analyze L. major parasites isolated from patients with active lesions from different geographic areas in Iran in order to understand DNA polymorphisms within L. major species. Twenty-four isolates were identified as L. major by RFLP analysis of the ribosomal internal transcribed spacer 1 (ITS1) amplicons. These isolates were further studied by single-strand conformation polymorphism (SSCP) analysis and sequencing of ITS1 and ITS2. Data obtained from SSCP analysis of the ITS1 and ITS2 loci revealed three and four different patterns among all studied samples, respectively. Sequencing of ITS1 and ITS2 confirmed the results of SSCP analysis and showed the potential of the PCR-SSCP method for assessing genetic heterogeneity within L. major. Different patterns in ITS1 were due to substitution of one nucleotide, whereas in ITS2 the changes were defined by variation in the number of repeats in two polymorphic microsatellites. In total five genotypic groups LmA, LmB, LmC, LmD and LmE were identified among L. major isolates. The most frequent genotype, LmA, was detected in isolates collected from different endemic areas of cutaneous leishmaniasis in Iran. Genotypes LmC, LmD and LmE were found only in the new focus of CL in Damghan (Semnan province) and LmB was identified exclusively among isolates of Kashan focus (Isfahan province). The distribution of genetic polymorphisms suggests the existence of distinct endemic regions of L. major in Iran.

Methylenetetrahydrofolate reductase polymorphisms and therapy response in pediatric acute lymphoblastic leukemia.

PubMed

Aplenc, Richard; Thompson, Jennifer; Han, Peggy; La, Mei; Zhao, Huaqing; Lange, Beverly; Rebbeck, Timothy

2005-03-15

A significant portion of patients treated for pediatric acute lymphoblastic leukemia (ALL) relapse. We hypothesized that common polymorphisms with moderate effect sizes and large attributive risks could explain an important fraction of ALL relapses. Methylenetetrahydrofolate reductase (MTHFR) is central to folate metabolism and has two common functional polymorphisms (C677T and A1298G). Methotrexate (MTX), which interrupts folate metabolism, is a mainstay of pediatric ALL therapy. MTX inhibits the synthesis of dTMP needed for DNA replication by blocking the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate by MTHFR. We hypothesized that a deactivating MTHFR allele would increase ALL relapse risk by potentially increasing 5,10-methylenetetrahydrofolate and dTMP, enhancing DNA synthesis and thus opposing MTX. To test this hypothesis, we genotyped 520 patients on the Children's Cancer Study Group ALL study, CCG-1891. The MTHFR C677T variant allele was statistically significantly associated with relapse (chi2 = 4.38, P = 0.036). This association remained significant (hazard ratio = 1.82, P = 0.008), controlling for important covariates, and was more predictive of relapse than other predictors, including day 7 bone marrow response. The MTHFR C677T variant allele was not associated with an increased risk of toxicity or infection. The MTHFR A1298G polymorphism was not associated with altered risks of relapse, toxicity, or infection. Haplotype analysis showed six common haplotypes that did not provide additional information predictive for relapse. These data provide evidence that the MTHFR C677T polymorphism is a common genetic variant conferring a moderate relative risk and a high attributable risk for relapse in pediatric ALL patients.

Concomitance of oncogenic HPV types, CHEK2 gene mutations, and CYP1B1 gene polymorphism as an increased risk factor for malignancy.

PubMed

Banaszkiewicz, Monika; Constantinou, Maria; Pietrusiński, Michał; Kępczyński, Lukasz; Jędrzejczyk, Adam; Rożniecki, Marek; Marks, Piotr; Kałużewski, Bogdan

2013-01-01

Urinary bladder carcinoma ranks the fourth position in malignancy incidence rates in men (6.1%) and the 17th position in women (1.6%). In general, neoplastic diseases should be approached from two perspectives: prevention with implementation of prophylactic measures and early diagnostics. Prophylactics is possible in the preclinical phase of neoplasm, being both justified and plausible in patients from high-risk groups. Thus, it is particularly important to select such groups, not only by referring to environmental carcinogenic factors (occupational and extra-occupational) but also from genetic predisposition, which may be conductive for neoplasm formation. The mutations / polymorphisms of CHEK2 and CYP1B1 genes predispose to neoplasm via multiorgan mechanisms, while the human papilloma virus (HPV) may participate in the neoplastic transformation as an environmental factor. 131 patients with diagnosed urinary bladder cancer were qualified to the study. Mutations/polymorphisms of CHEK2 (IVS2 + 1G > A gene, 1100delC, del5395, I157T) and CYP1B1- 355T/T were identified by the PCR in DNA isolated directly from the tumor and from peripheral blood. The ELISA test was used for the studies of 37 HPV genotypes in DNA, isolated tumour tissue. 11 mutations of CHEK2 gene were found, 355T/T polymorphism if CYP1B1 gene occurred in 18 patients (12.9%). Oncogenic HPV was found in 36 (29.3%), out of 123 examined patients. The concomitance of CHEK2 gene mutations or 355T/T polymorphism of CYP1B1 gene and the presence of oncogenic HPV types statistically significantly correlates with histological malignancy grades of urinary bladder carcinoma.

CCAAT/enhancer-binding protein alpha (CEBPA) polymorphisms and mutations in healthy individuals and in patients with peripheral artery disease, ischaemic heart disease and hyperlipidaemia.

PubMed

Fuchs, O; Kostecka, A; Provazníková, D; Krásná, B; Kotlín, R; Stanková, M; Kobylka, P; Dostálová, G; Zeman, M; Chochola, M

2010-01-01

The CCAAT/enhancer-binding protein alpha, encoded by the intronless CEBPA gene, is a transcription factor that induces expression of genes involved in differentiation of granulocytes, monocytes, adipocytes and hepatocytes. Both mono- and bi-allelic CEBPA mutations were detected in acute myeloid leukaemia and myelodysplastic syndrome. In this study we also identified CEBPA mutations in healthy individuals and in patients with peripheral artery disease, ischaemic heart disease and hyperlipidaemia. We found 16 various deletions with the presence of two direct repeats in CEBPA by analysis of 431 individuals. Three most frequent repeats included in these deletions in CEBPA gene are CGCGAG (493- 498_865-870), GG (486-487_885-886), and GCCAAGCAGC (508-517_907-916), all according to GenBank Accession No. NM_004364.2. In one case we identified that a father with ischaemic heart disease and his healthy son had two identical deletions (493_864del and 508_906del, both according to GenBank Accession No. NM_004364.2) in CEBPA. The occurrence of deletions between two repetitive sequences may be caused by recombination events in the repair process. A double-stranded cut in DNA may initiate these recombination events in adjacent DNA sequences. Four types of polymorphisms in the CEBPA gene were also detected in the screened individuals. Polymorphism in CEBPA gene 690 G>T according to GenBank Accession No. NM_004364.2 is the most frequent type in our analysis. Statistical analysis did not find significant differences in the frequency of polymorphisms in CEBPA in patients and in healthy individuals with the exception of P4 polymorphism (580_585dup according to GenBank Accesion No. NM_004364.2). P4 polymorphism was significantly increased in ischaemic heart disease patients.

APPLICATION OF DNA MICROARRAYS TO REPRODUCTIVE TOXICOLOGY AND THE DEVELOPMENT OF A TESTIS ARRAY

EPA Science Inventory

With the advent of sequence information for entire mammalian genomes, it is now possible to analyze gene expression and gene polymorphisms on a genomic scale. The primary tool for analysis of gene expression is the DNA microarray. We have used commercially available cDNA micro...

Checking of individuality by DNA profiling.

PubMed

Brdicka, R; Nürnberg, P

1993-08-25

A review of methods of DNA analysis used in forensic medicine for identification, paternity testing, etc. is provided. Among other techniques, DNA fingerprinting using different probes and polymerase chain reaction-based techniques such as amplified sequence polymorphisms and minisatellite variant repeat mapping are thoroughly described and both theoretical and practical aspects are discussed.

Characterization of early follicular cDNA library suggests evidence for genetic polymorphisms in the inbred strain C108 of Bombyx mori.

PubMed

Mills, D R; Goldsmith, M R

2000-04-01

Recent work towards the completion of a saturated molecular genetic linkage map for the lepidopteran silkworm, Bombyx mori (n = 28), has provided evidence for existing polymorphisms in the inbred strain C108. Two inbred parental strains, p50 and C108, were crossed to produce the F1 (P/C) hybrid offspring. The populations used in this project were comprised of a combination of 29 F2 (F1 x F1) and 31 reciprocal backcross (P/C x C/C, P/C x P/P) progeny. All restriction fragment length polymorphisms (RFLPs) for the initial analysis were hybridized with anonymous probes derived from a random early follicular cDNA (Rcf) library from Bombyx. A total of 19 Rcf probes were selected as showing scorable codominant polymorphic patterns when screened against F2 and backcross DNAs digested with the restriction enzymes EcoRI, HindIII, or PstI, and Southern blotted to nylon membranes for hybridization. Of the newly reported Rcf probes, 7 (37%) were characterized as producing 'simple' polymorphic patterns, while 12 (63%) were characterized as producing 'complex' polymorphic patterns. Further characterization of the complex patterns subdivided this group into two general classes: polymorphisms that contained an additional allele, and multiple bands that contained an easily scored two banded polymorphism. Because the extra allele class was limited to the (P/C x C/C) backcross progeny, it is suggested that the inbred parental strain C108 harbors polymorphic loci that are inherited in a simple Mendelian fashion. A genetic analysis discussing plausible origins and maintenance of these polymorphisms is presented.

The hOGG1 Ser326Cys polymorphism contributes to digestive system cancer susceptibility: evidence from 48 case-control studies.

PubMed

Wang, Yang; Gao, Xujie; Wei, Feng; Zhang, Xinwei; Yu, Jinpu; Zhao, Hua; Sun, Qian; Yan, Fan; Yan, Cihui; Li, Hui; Ren, Xiubao

2015-02-01

The Ser326Cys polymorphism in the human 8-oxogunaine DNA glycosylase (hOGG1) gene had been implicated in cancer susceptibility. Studies investigating the associations between the Ser326Cys polymorphism and digestion cancer susceptibility showed conflicting results. Therefore, a meta-analysis was performed to derive a more precise estimation of the relationship. We conducted a meta-analysis of 48 studies that included 12,073 cancer cases and 19,557 case-free controls. We assessed the strength of the association using odds ratios (ORs) with 95% confidence intervals (CIs). In our analysis, the hOGG1 Ser326Cys polymorphism was significantly associated with the risk of digestive system cancers (Cys/Cys vs. Ser/Ser: OR = 1.17, 95% CI = 1.00-1.35, P < 0.001; Cys/Cys vs. Cys/Ser + Ser/Ser: OR = 1.14, 95% CI = 1.00-1.29, P < 0.001). In subgroup analyses by cancer types, we found that the hOGG1 Ser326Cys polymorphism may increase hepatocellular cancer and colorectal cancer risks, but decrease the risk of oral cancer. These findings supported that hOGG1 Ser326Cys polymorphism may contribute to the susceptibility of digestive cancers.

Detection of IL28B SNP DNA from Buccal Epithelial Cells, Small Amounts of Serum, and Dried Blood Spots

PubMed Central

Halfon, Philippe; Ouzan, Denis; Khiri, Hacène; Pénaranda, Guillaume; Castellani, Paul; Oulès, Valerie; Kahloun, Asma; Amrani, Nolwenn; Fanteria, Lise; Martineau, Agnès; Naldi, Lou; Bourlière, Marc

2012-01-01

Background & Aims Point mutations in the coding region of the interleukin 28 gene (rs12979860) have recently been identified for predicting the outcome of treatment of hepatitis C virus infection. This polymorphism detection was based on whole blood DNA extraction. Alternatively, DNA for genetic diagnosis has been derived from buccal epithelial cells (BEC), dried blood spots (DBS), and genomic DNA from serum. The aim of the study was to investigate the reliability and accuracy of alternative routes of testing for single nucleotide polymorphism allele rs12979860CC. Methods Blood, plasma, and sera samples from 200 patients were extracted (400 µL). Buccal smears were tested using an FTA card. To simulate postal delay, we tested the influence of storage at ambient temperature on the different sources of DNA at five time points (baseline, 48 h, 6 days, 9 days, and 12 days) Results There was 100% concordance between blood, plasma, sera, and BEC, validating the use of DNA extracted from BEC collected on cytology brushes for genetic testing. Genetic variations in HPTR1 gene were detected using smear technique in blood smear (3620 copies) as well as in buccal smears (5870 copies). These results are similar to those for whole blood diluted at 1/10. A minimum of 0.04 µL, 4 µL, and 40 µL was necessary to obtain exploitable results respectively for whole blood, sera, and plasma. No significant variation between each time point was observed for the different sources of DNA. IL28B SNPs analysis at these different time points showed the same results using the four sources of DNA. Conclusion We demonstrated that genomic DNA extraction from buccal cells, small amounts of serum, and dried blood spots is an alternative to DNA extracted from peripheral blood cells and is helpful in retrospective and prospective studies for multiple genetic markers, specifically in hard-to-reach individuals. PMID:22412970

Detection of Rickettsia felis in Wild Mammals from Three Municipalities in Yucatan, Mexico.

PubMed

Panti-May, Jesús Alonso; Torres-Castro, Marco; Hernández-Betancourt, Silvia; Dzul-Rosado, Karla; Zavala-Castro, Jorge; López-Avila, Karina; Tello-Martín, Raúl

2015-09-01

The aim of this study was to provide information of the occurrence of Rickettsia felis in wild mammals from three municipalities in Yucatan, Mexico. The reactivity of rodent serum to Rickettsia antigens was detected in 80.9% (17 of 21) samples using immunofluorescence assay. Polymerase chain reaction identified rickettsial DNA in spleens of 43.5% (10 of 23) rodents and 57.1% (4 of 7) opossums. The identification of the rickettsial DNA was confirmed as R. felis by restriction fragment length polymorphism and DNA sequencing. This study comprises the first report of R. felis detection in wild mammals in Yucatan.

Association and family studies of DRD2 gene polymorphisms in alcohol dependence syndrome.

PubMed

Małecka, Iwona; Jasiewicz, Andrzej; Suchanecka, Aleksandra; Samochowiec, Jerzy; Grzywacz, Anna

2014-11-06

The human dopamine receptor 2 gene DRD2 plays a central role in susceptibility to Alcohol Dependence Syndrome (ADS). The aim of this study was to evaluate 3 single nucleotide polymorphisms: D2 (rs1076560), Tag1D (rs1800498), Tag1B (rs1079597) located in dopamine receptor 2 DRD2 gene and its role in alcohol dependence. DNA was provided from alcohol dependent (AD) patients (n=171) and healthy control subjects (n=160) all of Polish descent. The history of alcoholism was obtained using the Polish version of the SSAGA (Semi-Structured Assessment for the Genetics of Alcoholism). We conducted case-control association study and transmission disequilibrium test (TDT). Samples were genotyped using real-time PCR method. We did not confirm the association between studied polymorphisms and alcohol dependence syndrome. TDT reveled an adequate transmission of both alleles in the group of alcohol families. The lack of association of studied polymorphisms and ADS does not preclude its participation in the pathogenesis. Further research is needed to determine the actual contribution of DRD2 gene in the pathogenesis of alcoholism.

Discovery of human inversion polymorphisms by comparative analysis of human and chimpanzee DNA sequence assemblies.

PubMed

Feuk, Lars; MacDonald, Jeffrey R; Tang, Terence; Carson, Andrew R; Li, Martin; Rao, Girish; Khaja, Razi; Scherer, Stephen W

2005-10-01

With a draft genome-sequence assembly for the chimpanzee available, it is now possible to perform genome-wide analyses to identify, at a submicroscopic level, structural rearrangements that have occurred between chimpanzees and humans. The goal of this study was to investigate chromosomal regions that are inverted between the chimpanzee and human genomes. Using the net alignments for the builds of the human and chimpanzee genome assemblies, we identified a total of 1,576 putative regions of inverted orientation, covering more than 154 mega-bases of DNA. The DNA segments are distributed throughout the genome and range from 23 base pairs to 62 mega-bases in length. For the 66 inversions more than 25 kilobases (kb) in length, 75% were flanked on one or both sides by (often unrelated) segmental duplications. Using PCR and fluorescence in situ hybridization we experimentally validated 23 of 27 (85%) semi-randomly chosen regions; the largest novel inversion confirmed was 4.3 mega-bases at human Chromosome 7p14. Gorilla was used as an out-group to assign ancestral status to the variants. All experimentally validated inversion regions were then assayed against a panel of human samples and three of the 23 (13%) regions were found to be polymorphic in the human genome. These polymorphic inversions include 730 kb (at 7p22), 13 kb (at 7q11), and 1 kb (at 16q24) fragments with a 5%, 30%, and 48% minor allele frequency, respectively. Our results suggest that inversions are an important source of variation in primate genome evolution. The finding of at least three novel inversion polymorphisms in humans indicates this type of structural variation may be a more common feature of our genome than previously realized.

High-dose folic acid supplementation alters the human sperm methylome and is influenced by the MTHFR C677T polymorphism

PubMed Central

Aarabi, Mahmoud; San Gabriel, Maria C.; Chan, Donovan; Behan, Nathalie A.; Caron, Maxime; Pastinen, Tomi; Bourque, Guillaume; MacFarlane, Amanda J.; Zini, Armand; Trasler, Jacquetta

2015-01-01

Dietary folate is a major source of methyl groups required for DNA methylation, an epigenetic modification that is actively maintained and remodeled during spermatogenesis. While high-dose folic acid supplementation (up to 10 times the daily recommended dose) has been shown to improve sperm parameters in infertile men, the effects of supplementation on the sperm epigenome are unknown. To assess the impact of 6 months of high-dose folic acid supplementation on the sperm epigenome, we studied 30 men with idiopathic infertility. Blood folate concentrations increased significantly after supplementation with no significant improvements in sperm parameters. Methylation levels of the differentially methylated regions of several imprinted loci (H19, DLK1/GTL2, MEST, SNRPN, PLAGL1, KCNQ1OT1) were normal both before and after supplementation. Reduced representation bisulfite sequencing (RRBS) revealed a significant global loss of methylation across different regions of the sperm genome. The most marked loss of DNA methylation was found in sperm from patients homozygous for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, a common polymorphism in a key enzyme required for folate metabolism. RRBS analysis also showed that most of the differentially methylated tiles were located in DNA repeats, low CpG-density and intergenic regions. Ingenuity Pathway Analysis revealed that methylation of promoter regions was altered in several genes involved in cancer and neurobehavioral disorders including CBFA2T3, PTPN6, COL18A1, ALDH2, UBE4B, ERBB2, GABRB3, CNTNAP4 and NIPA1. Our data reveal alterations of the human sperm epigenome associated with high-dose folic acid supplementation, effects that were exacerbated by a common polymorphism in MTHFR. PMID:26307085

Genes tagging and molecular diversity of red rot susceptible/tolerant sugarcane hybrids using c-DNA and unigene derived markers.

PubMed

Singh, R K; Singh, R B; Singh, S P; Sharma, M L

2012-04-01

Sugarcane is an important international commodity as a valuable agricultural crop especially in tropical and subtropical countries. Two bulked DNA used to screen polymorphic primers from commercial hybrids (varieties) with moderately resistant and highly susceptible to red rot disease. Among 145 simple sequence repeat and unigene primers screened, 37 (25%) were found to be highly robust and polymorphic with Polymorphism Information Content values ranging from 0.50 to 1.00 with the mean value of 0.82. Among these microsatellites, twenty one were used in the study of genetic relationships and marker identification in sugarcane varieties for red rot resistance. A total of 105 polymorphic DNA bands were identified, with their fragment size ranging from 54 to 1,280 bp. Jaccard's similarity coefficient value recorded between closely related hybrids was 0.986 while lowest coefficient value of 0.341 was detected with distantly related hybrids. The average similarity coefficient among these hybrids was 0.663. Cluster analysis resulted in a dendrogram with two major clusters separating the moderately resistant varieties from highly susceptible varieties. Three group specific fragments amplified by unigene Saccharum microsatellite primers viz; two markers UGSM316(850) and UGSM316(60) were closely associated with moderately resistant varieties by appearing bands in this region but the bands were absent in highly susceptible varieties. Similarly UGSM316(400) marker was tightly linked with highly susceptible varieties by amplifying uniformly in sugarcane varieties showing highly susceptible reaction to red rot but it was absent in moderately resistant varietal groups. Validation of red rot resistance/susceptibility associated markers on a group of different mapping populations for red rot resistant/susceptible traits is in progress.

hOGG1 Ser326Cys polymorphism and G:C-to-T:A mutations: no evidence for a role in tobacco-related non small cell lung cancer.

PubMed

Hu, Ying Chuan; Ahrendt, Steven A

2005-04-10

Human 8-oxoguanine DNA glycosylase 1 (hOGG1) plays a major role in the repair of 8-hydroxyguanine, one of the major forms of DNA damage generated by reactive oxygen species in tobacco smoke. If left unrepaired by hOGG1, 8-hydroxyguanine can produce G:C-to-T:A transversions. Recent studies have suggested that the hOGG1 Ser326Cys polymorphism is associated with both a decrease in enzyme activity and an increased risk of lung cancer. To define the interaction between tobacco carcinogens, hOGG1-mediated DNA repair and DNA damage, we examined the role of the hOGG1 Ser326Cys polymorphism in mutation of the p53 gene in non small cell lung cancer (NSCLC). Tumor and nonneoplastic DNA were collected from 141 cigarette smokers with NSCLC. p53 mutations were detected by direct dideoxy sequencing and/or the GeneChip p53 assay in 74 of the 141 (52%) tumors. hOGG1 codon 326 polymorphisms were identified by polymerase chain reaction-restriction fragment length polymorphism analysis. The distribution of hOGG1 codon 326 genotypes was Ser/Ser, 90 of 141 (64%); Ser/Cys, 45 of 141 (32%); and Cys/Cys, 6 of 141 (4%). p53 mutations were significantly (p = 0.04) less common in NSCLC from patients with codon 326 Ser/Cys or Cys/Cys genotypes (21 of 51; 41%) than in NSCLC from Ser/Ser homozygotes (53 of 90; 59%). The decrease in p53 mutation frequency among carriers of the Cys allele was more evident in lung squamous cell cancer [7 of 17 (41%) for Cys/Cys and Ser/Cys vs. 27 of 38 (71%) for Ser/Ser; p = 0.04] than in nonbronchoalveolar adenocarcinoma [11 of 26 (42%) for Cys/Cys and Ser/Cys vs. 20 of 35 (57%) for Ser/Ser; p = 0.25]. The prevalence of G:C-to-T:A transversions was similar among hOGG1 codon 326 genotypes. In summary, the hOGG1 codon 326 Cys allele was associated with a decrease in p53 mutations and no effect on G:C-to-T:A transversions in NSCLC. This decrease in p53 mutations in vivo is not consistent with a decrease in the repair of 8-hydroxyguanine among carriers of the hOGG1 codon 326 Cys allele in vitro. (c) 2004 Wiley-Liss, Inc.

Differential structural status of the RNA counterpart of an undecamer quasi-palindromic DNA sequence present in LCR of human β-globin gene cluster.

PubMed

Kaushik, Mahima; Kukreti, Shrikant

2015-01-01

Our previous work on structural polymorphism shown at a single nucleotide polymorphism (SNP) (A → G) site located on HS4 region of locus control region (LCR) of β-globin gene has established a hairpin → duplex equilibrium corresponding to A → B like DNA transition (Kaushik M, Kukreti, R., Grover, D., Brahmachari, S.K. and Kukreti S. Nucleic Acids Res. 2003; Kaushik M, Kukreti S. Nucleic Acids Res. 2006). The G-allele of A → G SNP has been shown to be significantly associated with the occurrence of β-thalassemia. Considering the significance of this 11-nt long quasi-palindromic sequence [5'-TGGGG(G/A)CCCCA; HP(G/A)11] of β-globin gene LCR, we further explored the differential behavior of the same DNA sequence with its RNA counterpart, using various biophysical and biochemical techniques. In contrast to its DNA counterpart exhibiting a A → B structural transition and an equilibrium between duplex and hairpin forms, the studied RNA oligonucleotide sequence [5'-UGGGG(G/A)CCCCA; RHP(G/A)11] existed only in duplex form (A-conformation) and did not form hairpin. The single residue difference from A to G led to the unusual thermal stability of the RNA structure formed by the studied sequence. Since, naturally occurring mutations and various SNP sites may stabilize or destabilize the local DNA/RNA secondary structures, these structural transitions may affect the gene expression by a change in the protein-DNA recognition patterns.

Philopatry of male marine turtles inferred from mitochondrial DNA markers

PubMed Central

FitzSimmons, Nancy N.; Limpus, Colin J.; Norman, Janette A.; Goldizen, Alan R.; Miller, Jeffrey D.; Moritz, Craig

1997-01-01

Recent studies of mitochondrial DNA (mtDNA) variation among marine turtle populations are consistent with the hypothesis that females return to beaches in their natal region to nest as adults. In contrast, less is known about breeding migrations of male marine turtles and whether they too are philopatric to natal regions. Studies of geographic structuring of restriction fragment and microsatellite polymorphisms at anonymous nuclear loci in green turtle (Chelonia mydas) populations indicate that nuclear gene flow is higher than estimates from mtDNA analyses. Regional populations from the northern and southern Great Barrier Reef were distinct for mtDNA but indistinguishable at nuclear loci, whereas the Gulf of Carpentaria (northern Australia) population was distinct for both types of marker. To assess whether this result was due to reduced philopatry of males across the Great Barrier Reef, we determined the mtDNA haplotypes of breeding males at courtship areas for comparison with breeding females from the same three locations. We used a PCR-restriction fragment length polymorphism approach to determine control region haplotypes and designed mismatch primers for the identification of specific haplotypes. The mtDNA haplotype frequencies were not significantly different between males and females at any of the three areas and estimates of Fst among the regions were similar for males and females (Fst = 0.78 and 0.73, respectively). We conclude that breeding males, like females, are philopatric to courtship areas within their natal region. Nuclear gene flow between populations is most likely occurring through matings during migrations of both males and females through nonnatal courtship areas. PMID:9238077

New polymorphic markers in the vicinity of the pearl locus on mouse chromosome 13.

PubMed

Xu, H P; Yanak, B L; Wigler, M H; Gorin, M B

1996-01-01

We have used a Mus domesticus/-Mus spretus congenic animal that was selected for retention of Mus spretus DNA around the pearl locus to create a highly polymorphic region suitable for screening new markers. Representation difference analysis (RDA) was performed with either DNA from the congenic animal or C57BL/6J as the driver for subtraction. Four clones were identified, characterized, and converted to PCR-based polymorphic markers. Three of the four markers equally subdivide a 10-cM interval containing the pearl locus, with the fourth located centromeric to it. These markers have been placed on the mouse genetic map by use of an interspecific backcross panel between Mus domesticus (C57BL/6J) and Mus spretus generated by The Jackson Laboratory.

Impact of the Ile105Val Polymorphism of the Glutathione S-transferase P1 (GSTP1) Gene on Obesity and Markers of Cardiometabolic Risk in Young Adult Population.

PubMed

Chielle, E O; Trott, A; da Silva Rosa, B; Casarin, J N; Fortuna, P C; da Cruz, I B M; Moretto, M B; Moresco, R N

2017-05-01

The aim of the study was to investigate the association between Glutathione S-transferase P1 (GSTP1) gene polymorphism with obesity and markers of cardiometabolic risk. A cross-sectional study was carried out in individuals aged≥18 and ≤30 years. The study included 54 normal weight, 27 overweight and 68 obese volunteers. Anthropometric measurements and biochemical parameters were evaluated, the DNA was extracted from blood samples and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to measure GSTP1 Ile 105 Val gene polymorphism of the study participants. Also, biochemical analysis and hormone assays were carried out. A positive association between GSTP1 polymorphism and obesity was observed on subjects carrying at least one G allele (AG and GG). GG genotype was found only in the obese group. The G allele carriers presented 2.4 times higher chance of obesity when compared to those with the AA genotype. These results were independent of sex and age. We suggest that despite a study in population regional (south of Brazil), the GSTP1 gene polymorphism may play a significant role in the increase of susceptibility of obesity and contribute to identify the cardiovascular risk in young adults. © Georg Thieme Verlag KG Stuttgart · New York.

A meta-analysis of xeroderma pigmentosum gene D Ls751Gln polymorphism and susceptibility to hepatocellular carcinoma.

PubMed

Wang, Yu; Zhao, Yingren; Zhang, Aiyun; Ma, Juan; Wang, Zhenzhen; Zhang, Xu

2015-01-01

Hepatocellular carcinoma (HCC) is one of most common malignant tumors worldwide, but with unclear mechanisms. Xeroderma pigmentosum gene D (XPD) is one important DNA damage repair gene and can be involved in protein mutation. Currently little has been known about XPD polymorphism and HCC susceptibility in Chinese people. This study used a meta-analysis approach to comprehensively investigate the correlation between XPD polymorphism and HCC susceptibility in Chinese population, based on previously published literatures. A computer retrieval system was used to collect all case-control studies about XPD Lys751Gln polymorphism and HCC susceptibility. Data in literatures were extracted for meta-analysis. After the primary screening, four independent studies, which were published in 3 English articles and one Chinese article, were recruited in this study. There were 1,717 samples included in all studies. Using Gln/Gln + Lys/Gln, Lys/Lys + Lys/Gln and Lys allels as the reference, HCC disease alleles including Lys/Lys, Gln/Gln and Gln had OR values (95% CI, I(2)) of 1.007 (0.657~4.672, 91%), 3.516 (0.220~20.661, 48%) and 3.225 (0.278~12.326, 84%), respectively. The polymorphism of XPD751 loci is closely correlated with primary HCC. Lys751Gln polymorphism of XPD gene can be used as one susceptibility factor for HCC.

Overstretching of B-DNA with various pulling protocols: Appearance of structural polymorphism and S-DNA

NASA Astrophysics Data System (ADS)

Garai, Ashok; Mogurampelly, Santosh; Bag, Saientan; Maiti, Prabal K.

2017-12-01

We report a structural polymorphism of the S-DNA when a canonical B-DNA is stretched under different pulling protocols and provide a fundamental molecular understanding of the DNA stretching mechanism. Extensive all atom molecular dynamics simulations reveal a clear formation of S-DNA when the B-DNA is stretched along the 3' directions of the opposite strands (OS3) and is characterized by the changes in the number of H-bonds, entropy, and free energy. Stretching along the 5' directions of the opposite strands (OS5) leads to force induced melting form of the DNA. Interestingly, stretching along the opposite ends of the same strand leads to a coexistence of both the S- and melted M-DNA structures. We also do the structural characterization of the S-DNA by calculating various helical parameters. We find that the S-DNA has a twist of ˜10° which corresponds to a helical repeat length of ˜36 base pairs in close agreement with the previous experimental results. Moreover, we find that the free energy barrier between the canonical and overstretched states of DNA is higher for the same termini pulling protocol in comparison to all other protocols considered in this work. Overall, our observations not only reconcile with the available experimental results qualitatively but also enhance the understanding of different overstretched DNA structures.

Molecular profiles of Venezuelan isolates of Trypanosoma sp. by random amplified polymorphic DNA method.

PubMed

Perrone, T M; Gonzatti, M I; Villamizar, G; Escalante, A; Aso, P M

2009-05-12

Nine Trypanosoma sp. Venezuelan isolates, initially presumed to be T. evansi, were collected from three different hosts, capybara (Apure state), horse (Apure state) and donkey (Guarico state) and compared by the random amplification polymorphic DNA technique (RAPD). Thirty-one to 46 reproducible fragments were obtained with 12 of the 40 primers that were used. Most of the primers detected molecular profiles with few polymorphisms between the seven horse, capybara and donkey isolates. Quantitative analyses of the RAPD profiles of these isolates revealed a high degree of genetic conservation with similarity coefficients between 85.7% and 98.5%. Ten of the primers generated polymorphic RAPD profiles with two of the three Trypanosoma sp. horse isolates, namely TeAp-N/D1 and TeGu-N/D1. The similarity coefficient between these two isolates and the rest, ranged from 57.9% to 68.4% and the corresponding dendrogram clustered TeAp-N/D1 and Te Gu-N/D1 in a genetically distinct group.

A polymorphic DNA marker that represents a conserved expressed sequence in the region of the Huntington disease gene.

PubMed Central

Hayden, M R; Hewitt, J; Wasmuth, J J; Kastelein, J J; Langlois, S; Conneally, M; Haines, J; Smith, B; Hilbert, C; Allard, D

1988-01-01

A polymorphic marker (D4S62) that is genetically closely linked to D4S10 and is in the region of the gene for Huntington disease is described. A four-allele polymorphism is detected when HincII-digested DNA is hybridized with D4S62. D4S62 maps, by Southern blot analysis using somatic-cell hybrids, to 4p16.1 closer to the centromere than does D4S10. The use of the polymorphisms detected by D4S62 increases the informativeness of markers close to the gene for Huntington disease and will be useful for preclinical diagnosis. D4S62 detects transcripts of approximately 6,000 nucleotides in rat, mouse, and monkey liver and brain. This represents the first demonstration of conserved expressed sequences close to the gene for Huntington disease. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 PMID:2892395

Development of SCAR Markers for the DNA-Based Detection of the Asian Long-Horned Beetle; Anoplophora glabripennis (Motschulsky)

Treesearch

Damodar R. Kethidi; David B. Roden; Tim R. Ladd; Peter J. Krell; Arthur Ratnakaran; Qili Feng

2003-01-01

DNA markers were identified for the molecular detection of the Asian long-horned beetle (ALB), Anoplophora glabripennis (Mot.), based on sequence charaterized amplified regions (SCARS) derived from random amplified polymorphic DNA (RAPD) fragments. A 2,740-bp DNA fragment that was present only in ALB and not in other Cerambycids was identified after...

DNA fingerprinting of Chinese melon provides evidentiary support of seed quality appraisal.

PubMed

Gao, Peng; Ma, Hongyan; Luan, Feishi; Song, Haibin

2012-01-01

Melon, Cucumis melo L. is an important vegetable crop worldwide. At present, there are phenomena of homonyms and synonyms present in the melon seed markets of China, which could cause variety authenticity issues influencing the process of melon breeding, production, marketing and other aspects. Molecular markers, especially microsatellites or simple sequence repeats (SSRs) are playing increasingly important roles for cultivar identification. The aim of this study was to construct a DNA fingerprinting database of major melon cultivars, which could provide a possibility for the establishment of a technical standard system for purity and authenticity identification of melon seeds. In this study, to develop the core set SSR markers, 470 polymorphic SSRs were selected as the candidate markers from 1219 SSRs using 20 representative melon varieties (lines). Eighteen SSR markers, evenly distributed across the genome and with the highest contents of polymorphism information (PIC) were identified as the core marker set for melon DNA fingerprinting analysis. Fingerprint codes for 471 melon varieties (lines) were established. There were 51 materials which were classified into17 groups based on sharing the same fingerprint code, while field traits survey results showed that these plants in the same group were synonyms because of the same or similar field characters. Furthermore, DNA fingerprinting quick response (QR) codes of 471 melon varieties (lines) were constructed. Due to its fast readability and large storage capacity, QR coding melon DNA fingerprinting is in favor of read convenience and commercial applications.

DNA Fingerprinting of Chinese Melon Provides Evidentiary Support of Seed Quality Appraisal

PubMed Central

Gao, Peng; Ma, Hongyan; Luan, Feishi; Song, Haibin

2012-01-01

Melon, Cucumis melo L. is an important vegetable crop worldwide. At present, there are phenomena of homonyms and synonyms present in the melon seed markets of China, which could cause variety authenticity issues influencing the process of melon breeding, production, marketing and other aspects. Molecular markers, especially microsatellites or simple sequence repeats (SSRs) are playing increasingly important roles for cultivar identification. The aim of this study was to construct a DNA fingerprinting database of major melon cultivars, which could provide a possibility for the establishment of a technical standard system for purity and authenticity identification of melon seeds. In this study, to develop the core set SSR markers, 470 polymorphic SSRs were selected as the candidate markers from 1219 SSRs using 20 representative melon varieties (lines). Eighteen SSR markers, evenly distributed across the genome and with the highest contents of polymorphism information (PIC) were identified as the core marker set for melon DNA fingerprinting analysis. Fingerprint codes for 471 melon varieties (lines) were established. There were 51 materials which were classified into17 groups based on sharing the same fingerprint code, while field traits survey results showed that these plants in the same group were synonyms because of the same or similar field characters. Furthermore, DNA fingerprinting quick response (QR) codes of 471 melon varieties (lines) were constructed. Due to its fast readability and large storage capacity, QR coding melon DNA fingerprinting is in favor of read convenience and commercial applications. PMID:23285039

A novel single-nucleotide polymorphism of the visfatin gene and its associations with performance traits in the chicken.

PubMed

Han, R-L; Lan, X-Y; Zhang, L-Z; Ren, G; Jing, Y-J; Li, M-J; Zhang, B; Zhao, M; Guo, Y-K; Kang, X-T; Chen, H

2010-01-01

Visfatin is a peptide that is predominantly expressed in visceral adipose tissue and is hypothesized to be related to obesity and insulin resistance. In this study, a novel silent single-nucleotide polymorphism (SNP) was found in exon 7 of the chicken visfatin gene (also known as PBEF1) by single-stranded conformation polymorphism (SSCP) and DNA sequencing. In total, 836 chickens forming an F2 resource population of Gushi chicken crossed with Anka broiler were genotyped by XbaI forced RFLP, and the associations of this polymorphism with chicken growth, carcass characteristics, and meat quality were analyzed. Significant associations were found between the polymorphism and 4-week body weight (BW4), 6-week body weight (BW6), 4-week body slanting length (BSL4), fat bandwidth (FBW), breast muscle water loss rate (BWLR) and breast muscle fiber density (BFD) (P < 0.05), as well as 4-week breastbone length (BBL4) (P < 0.01). These observations suggested that the polymorphism in exon7 of the visfatin gene had significant effects on the early growth traits of chicken.

Genomic polymorphism, recombination, and linkage disequilibrium in human major histocompatibility complex-encoded antigen-processing genes.

PubMed Central

van Endert, P M; Lopez, M T; Patel, S D; Monaco, J J; McDevitt, H O

1992-01-01

Recently, two subunits of a large cytosolic protease and two putative peptide transporter proteins were found to be encoded by genes within the class II region of the major histocompatibility complex (MHC). These genes have been suggested to be involved in the processing of antigenic proteins for presentation by MHC class I molecules. Because of the high degree of polymorphism in MHC genes, and previous evidence for both functional and polypeptide sequence polymorphism in the proteins encoded by the antigen-processing genes, we tested DNA from 27 consanguineous human cell lines for genomic polymorphism by restriction fragment length polymorphism (RFLP) analysis. These studies demonstrate a strong linkage disequilibrium between TAP1 and LMP2 RFLPs. Moreover, RFLPs, as well as a polymorphic stop codon in the telomeric TAP2 gene, appear to be in linkage disequilibrium with HLA-DR alleles and RFLPs in the HLA-DO gene. A high rate of recombination, however, seems to occur in the center of the complex, between the TAP1 and TAP2 genes. Images PMID:1360671

Associations of Epstein-Barr Virus DNA in PBMCs and the Subtypes with Breast Cancer Risk

PubMed Central

Zhang, Wei; Wang, Min-Yi; Wei, Xue-Ling; Lin, Ying; Su, Feng-Xi; Xie, Xiao-Ming; Tang, Lu-Ying; Ren, Ze-Fang

2017-01-01

Objective: Epstein-Barr virus (EBV) has been found to be implicated in the development of breast cancer. The purpose of the present study was to identify the associations of EBV DNA and the subtypes in peripheral blood mononuclear cells (PBMCs) with the risk of breast cancer. Material and Methods: A case-control study with 671 breast cancer cases and 859 age-matched controls was conducted in Guangzhou, China. Face-to-face interviews were performed and blood samples were collected immediately after admission to the hospital for patients or after the interview for controls. EBV DNA in PBMCs and the subtypes were detected using Polymerase Chain Reaction (PCR) and restricted fragment length polymorphisms (RFLP). IgA antibodies against EBV VCA-p18 and EBNA-1 were examined using commercial enzyme-linked immunosorbent assay kits. Unconditional logistic regression analysis was applied to evaluate the associations of the DNA positivity and subtypes of EBV with the risk of breast cancer. Results: Among the 1530 subjects, 164 cases (24.4 %) and 206 controls (24.0 %) were positive for EBV DNA in PBMCs and no significant difference occurred between cases and controls. The presence of EBV DNA was related to the positivity of EBV IgA antibodies. Of the DNA positive samples, 71 cases and 109 controls for F/f subtype and 58 cases and 112 controls for C/D subtype were successfully obtained. The D subtype was associated with an increased breast cancer risk compared with the C subtype [OR (95% CI): 2.86 (1.25~6.53)]. We did not find an association of the F/f polymorphism with breast cancer risk. Conclusions: The present study suggested that the presence of EBV DNA in PBMCs may not be an appropriate biomarker for breast cancer risk. The subtype D of EBV was likely to be related to breast tumorigenesis. PMID:28928885

C677T polymorphism in the methylenetetrahydrofolate reductase gene is associated with primary closed angle glaucoma

PubMed Central

Michael, Shazia; Qamar, Raheel; Akhtar, Farah; Khan, Wajid Ali

2008-01-01

Purpose To determine whether or not there is an association of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with disease in cohorts of primary open-angle glaucoma (POAG) and primary closed-angle glaucoma (PCAG) from Pakistan. Methods This was a prospective study consisting of 150 patients (90 POAG and 60 PCAG) and 70 control subjects. Genomic DNA was extracted from leukocytes of the peripheral blood. MTHFR C677T polymorphism analysis was performed by the polymerase chain reaction-restriction fragment length polymorphism (RFLP) technique. Results The prevalence of the MTHFR C/T genotype was 22.2% in POAG, 13.3% in PACG, and 18.6% in controls whereas the MTHFR T/T genotype was present solely in the PACG group (6.9%). The difference regarding the T/T genotype between PACG and controls was statistically significant (p<0.01). Conclusions The MTHFR C677T polymorphism was found to be associated with PCAG but not POAG in patients of Pakistani origin. PMID:18385801

Methods for detection of ataxia telangiectasia mutations

DOEpatents

Gatti, Richard A.

2005-10-04

The present invention is directed to a method of screening large, complex, polyexonic eukaryotic genes such as the ATM gene for mutations and polymorphisms by an improved version of single strand conformation polymorphism (SSCP) electrophoresis that allows electrophoresis of two or three amplified segments in a single lane. The present invention also is directed to new mutations and polymorphisms in the ATM gene that are useful in performing more accurate screening of human DNA samples for mutations and in distinguishing mutations from polymorphisms, thereby improving the efficiency of automated screening methods.

Modified SSCP method using sequential electrophoresis of multiple nucleic acid segments

DOEpatents

Gatti, Richard A.

2002-10-01

The present invention is directed to a method of screening large, complex, polyexonic eukaryotic genes such as the ATM gene for mutations and polymorphisms by an improved version of single strand conformation polymorphism (SSCP) electrophoresis that allows electrophoresis of two or three amplified segments in a single lane. The present invention also is directed to new mutations and polymorphisms in the ATM gene that are useful in performing more accurate screening of human DNA samples for mutations and in distinguishing mutations from polymorphisms, thereby improving the efficiency of automated screening methods.

Lack of association between FokI polymorphism in vitamin D receptor gene (VDR) & type 2 diabetes mellitus in the Tunisian population

PubMed Central

Mahjoubi, Imen; Kallel, Amani; Sbaï, Mohamed Hédi; Ftouhi, Bochra; ben Halima, Meriam; Jemaa, Zeineb; Feki, Moncef; Slimane, Hedia; Jemaa, Riadh; Kaabachi, Naziha

2016-01-01

Background & objectives: The impact of several environmental and genetic factors on diabetes is well documented. Though the association between the vitamin D receptor (VDR) gene polymorphisms and type 2 diabetes mellitus (T2DM) has been analyzed in different ethnic groups, the results have been inconsistent. The aim of this study was to evaluate the possible association between VDR FokI polymorphism and genetic susceptibility to T2DM in Tunisian population. Methods: A total of 439 unrelated patients with T2DM and 302 healthy controls were included in the study. Genomic DNA was extracted from blood and genotyped for the single nucleotide polymorphism (SNP) of FokI (T/C: (rs2228570) by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. Results: The genotype distribution and the relative allelic frequencies for the FokI polymorphism were not significantly different between T2DM and controls: in T2DM patients the frequencies of the CC, CT, and TT genotypes were 52.6, 41.0, and 6.1 per cent, respectively, and in controls the genotype frequencies were 55.6, 38.7, and 5.6 per cent, respectively. In our study, the TT genotype of the FokI polymorphism was not associated with T2DM (OR =1.19, 95% CI 0.63 - 2.25, P=0.577). Interpretation & conclusions: Our study showed no significant association of the FokI polymorphism in the vitamin D receptor gene with type 2 diabetes mellitus in Tunisian population. PMID:27834325

Whole-loop mitochondrial DNA D-loop sequence variability in Egyptian Arabian equine matrilines

PubMed Central

Hudson, William

2017-01-01

Background Egyptian Arabian horses have been maintained in a state of genetic isolation for over a hundred years. There is only limited genetic proof that the studbook records of female lines of Egyptian Arabian pedigrees are reliable. This study characterized the mitochondrial DNA (mtDNA) signatures of 126 horses representing 14 matrilines in the Egyptian Agricultural Organization (EAO) horse-breeding program. Findings Analysis of the whole D-loop sequence yielded additional information compared to hypervariable region-1 (HVR1) analysis alone, with 42 polymorphic sites representing ten haplotypes compared to 16 polymorphic sites representing nine haplotypes, respectively. Most EAO haplotypes belonged to ancient haplogroups, suggesting origin from a wide geographical area over many thousands of years, although one haplotype was novel. Conclusions Historical families share haplotypes and some individuals from different strains belonged to the same haplogroup: the classical EAO strain designation is not equivalent to modern monophyletic matrilineal groups. Phylogenetic inference showed that the foundation mares of the historical haplotypes were highly likely to have the same haplotypes as the animals studied (p > 0.998 in all cases), confirming the reliability of EAO studbook records and providing the opportunity for breeders to confirm the ancestry of their horses. PMID:28859174

Association of transforming growth-factor alpha gene polymorphisms with nonsyndromic cleft palate only (CPO)

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

Shiang, R.; Lidral, A.C.; Ardinger, H.H.

1993-10-01

Genetic analysis and tissue-specific expression studies support a role for transforming growth-factor alpha (TGFA) in craniofacial development. Previous studies have confirmed an association of alleles for TGFA with nonsyndromic cleft lip with or without cleft palate (CL/P) in humans. The authors carried out a retrospective association study to determine whether specific allelic variants of the TGFA gene are also associated with cleft palate only (CPO). The PCR products from 12 overlapping sets of primers to the TGFA cDNA were examined by using single-strand conformational polymorphism analysis. Four DNA polymorphic sites for TGFA were identified in the 3[prime] untranslated region ofmore » the TGFA gene. These variants, as well as previously identified RFLPs for TGFA, were characterized in case and control populations for CPO by using X[sup 2] analysis. A significant association between alleles of TGFA and CPO was identified which further supports a role for this gene as one of the genetic determinants of craniofacial development. Sequence analysis of the variants disclosed a cluster of three variable sites within 30 bp of each other in the 3[prime] untranslated region previously associated with an antisense transcript. These studies extend the role for TGFA in craniofacial morphogenesis and support an interrelated mechanism underlying nonsyndromic forms of CL/P. 46 refs., 3 figs., 3 tabs.« less

Toll-like receptor 3 polymorphism rs3775291 is not associated with choroidal neovascularization or polypoidal choroidal vasculopathy in Chinese subjects.

PubMed

Sng, Chelvin C A; Cackett, Peter D; Yeo, Ian Y; Thalamuthu, Anbupalam; Venkatraman, Anandalakshmi; Venkataraman, Divya; Koh, Adrian H; Tai, E-Shyong; Wong, Tien Y; Aung, Tin; Vithana, Eranga N

2011-01-01

Age-related macular degeneration (AMD) is a leading cause of visual impairment. A single-nucleotide polymorphism (SNP; rs3775291) in the Toll-like receptor 3 (TLR3) gene has recently been implicated in the pathogenesis of AMD in Caucasian populations. The aim of this study was to examine this association in Chinese persons with choroidal neovascularization (CNV) secondary to AMD and polypoidal choroidal vasculopathy (PCV). This was an observational cross-sectional study in Singapore. Study subjects were of Chinese ethnicity and included patients with exudative maculopathy and normal control subjects. The diagnoses of CNV and PCV were made based on fundus examination, fluorescein angiography and indocyanine green angiography findings. Genomic DNA was extracted, and genotypes were determined by bidirectional DNA sequencing. We compared the allele and genotype frequencies between subjects with CNV and PCV with controls using the software PLINK. A total of 246 subjects with exudative maculopathy (consisting of 126 with CNV and 120 with PCV) and 274 normal control subjects were recruited. The distribution of rs3775291 SNP genotypes for CNV and PCV was not significantly different from that for normal controls. This study indicates that the TLR3 rs3775291 gene polymorphism is not associated with CNV and PCV in Singaporean Chinese patients. Copyright © 2010 S. Karger AG, Basel.

Evaluation of DNA extraction methods for the analysis of microbial community in biological activated carbon.

PubMed

Zheng, Lu; Gao, Naiyun; Deng, Yang

2012-01-01

It is difficult to isolate DNA from biological activated carbon (BAC) samples used in water treatment plants, owing to the scarcity of microorganisms in BAC samples. The aim of this study was to identify DNA extraction methods suitable for a long-term, comprehensive ecological analysis of BAC microbial communities. To identify a procedure that can produce high molecular weight DNA, maximizes detectable diversity and is relatively free from contaminants, the microwave extraction method, the cetyltrimethylammonium bromide (CTAB) extraction method, a commercial DNA extraction kit, and the ultrasonic extraction method were used for the extraction of DNA from BAC samples. Spectrophotometry, agarose gel electrophoresis and polymerase chain reaction (PCR)-restriction fragment length polymorphisms (RFLP) analysis were conducted to compare the yield and quality of DNA obtained using these methods. The results showed that the CTAB method produce the highest yield and genetic diversity of DNA from BAC samples, but DNA purity was slightly less than that obtained with the DNA extraction-kit method. This study provides a theoretical basis for establishing and selecting DNA extraction methods for BAC samples.

Nuclear Ribosomal DNA Variation and Pathogenic Specialization in Alternaria Fungi Known To Produce Host-Specific Toxins †

PubMed Central

Kusaba, Motoaki; Tsuge, Takashi

1994-01-01

A total of 99 strains of 11 Alternaria species, including 68 strains of seven fungi known to produce host-specific toxins, were subjected to analysis of restriction fragment length polymorphism (RFLP) in nuclear ribosomal DNA (rDNA). Total DNA was digested with XbaI, and the Southern blots were probed with a nuclear rDNA clone of Alternaria kikuchiana. The hybridization gave 17 different RFLPs from the 99 strains. On the basis of these RFLPs, populations of host-specific toxin-producing fungi could not be differentiated from one another nor from nonpathogenic A. alternata. Each population of the toxin-producing fungi carried rDNA variants. Nine different types, named A1 to A6 and B1 to B3, were detected among the toxin-producing fungi and nonpathogenic A. alternata. All of the populations contained the type A4 variant, and the other rDNA types were also shared by different toxin-producing fungi and A. alternata. In contrast, Alternaria species that are morphologically distinguishable from A. alternata could be differentiated from A. alternata on the basis of the rDNA RFLPs. Polymorphisms in rDNA digested with HaeIII and MspI were also evaluated in 61 Alternaria strains. These restriction enzymes produced 31 variations among all of the samples. The seven toxin-producing fungi and nonpathogenic A. alternata could not be resolved by phylogenetic analysis based on the RFLPs, although they could be differentiated from the other Alternaria species studied. These results provide support for the hypothesis that Alternaria fungi known to produce host-specific toxins are intraspecific variants of A. alternata specialized in pathogenicity. Images PMID:16349367

Genetic variants of the DNA repair genes from Exome Aggregation Consortium (EXAC) database: significance in cancer.

PubMed

Das, Raima; Ghosh, Sankar Kumar

2017-04-01

DNA repair pathway is a primary defense system that eliminates wide varieties of DNA damage. Any deficiencies in them are likely to cause the chromosomal instability that leads to cell malfunctioning and tumorigenesis. Genetic polymorphisms in DNA repair genes have demonstrated a significant association with cancer risk. Our study attempts to give a glimpse of the overall scenario of the germline polymorphisms in the DNA repair genes by taking into account of the Exome Aggregation Consortium (ExAC) database as well as the Human Gene Mutation Database (HGMD) for evaluating the disease link, particularly in cancer. It has been found that ExAC DNA repair dataset (which consists of 228 DNA repair genes) comprises 30.4% missense, 12.5% dbSNP reported and 3.2% ClinVar significant variants. 27% of all the missense variants has the deleterious SIFT score of 0.00 and 6% variants carrying the most damaging Polyphen-2 score of 1.00, thus affecting the protein structure and function. However, as per HGMD, only a fraction (1.2%) of ExAC DNA repair variants was found to be cancer-related, indicating remaining variants reported in both the databases to be further analyzed. This, in turn, may provide an increased spectrum of the reported cancer linked variants in the DNA repair genes present in ExAC database. Moreover, further in silico functional assay of the identified vital cancer-associated variants, which is essential to get their actual biological significance, may shed some lights in the field of targeted drug development in near future. Copyright © 2017. Published by Elsevier B.V.

A new single-nucleotide polymorphism database for rainbow trout generated through whole genome re-sequencing

USDA-ARS?s Scientific Manuscript database

Single-nucleotide polymorphisms (SNPs) are highly abundant markers, which are broadly distributed in animal genomes. For rainbow trout, SNP discovery has been done through sequencing of restriction-site associated DNA (RAD) libraries, reduced representation libraries (RRL), RNA sequencing, and whole...

Complex Relationships between Occupation, Environment, DNA Adducts, Genetic Polymorphisms and Bladder Cancer in a Case-Control Study Using a Structural Equation Modeling

PubMed Central

Porru, Stefano; Pavanello, Sofia; Carta, Angela; Arici, Cecilia; Simeone, Claudio; Izzotti, Alberto; Mastrangelo, Giuseppe

2014-01-01

DNA adducts are considered an integrate measure of carcinogen exposure and the initial step of carcinogenesis. Their levels in more accessible peripheral blood lymphocytes (PBLs) mirror that in the bladder tissue. In this study we explore whether the formation of PBL DNA adducts may be associated with bladder cancer (BC) risk, and how this relationship is modulated by genetic polymorphisms, environmental and occupational risk factors for BC. These complex interrelationships, including direct and indirect effects of each variable, were appraised using the structural equation modeling (SEM) analysis. Within the framework of a hospital-based case/control study, study population included 199 BC cases and 213 non-cancer controls, all Caucasian males. Data were collected on lifetime smoking, coffee drinking, dietary habits and lifetime occupation, with particular reference to exposure to aromatic amines (AAs) and polycyclic aromatic hydrocarbons (PAHs). No indirect paths were found, disproving hypothesis on association between PBL DNA adducts and BC risk. DNA adducts were instead positively associated with occupational cumulative exposure to AAs (p = 0.028), whereas XRCC1 Arg 399 (p<0.006) was related with a decreased adduct levels, but with no impact on BC risk. Previous findings on increased BC risk by packyears (p<0.001), coffee (p<0.001), cumulative AAs exposure (p = 0.041) and MnSOD (p = 0.009) and a decreased risk by MPO (p<0.008) were also confirmed by SEM analysis. Our results for the first time make evident an association between occupational cumulative exposure to AAs with DNA adducts and BC risk, strengthening the central role of AAs in bladder carcinogenesis. However the lack of an association between PBL DNA adducts and BC risk advises that these snapshot measurements are not representative of relevant exposures. This would envisage new scenarios for biomarker discovery and new challenges such as repeated measurements at different critical life stages. PMID:24722645

Production and characterization of interspecific somatic hybrids between Brassica oleracea var. botrytis and B. nigra and their progenies for the selection of advanced pre-breeding materials.

PubMed

Wang, Gui-xiang; Tang, Yu; Yan, Hong; Sheng, Xiao-guang; Hao, Wei-Wei; Zhang, Li; Lu, Kun; Liu, Fan

2011-10-01

Somatic hybridization is a potential method for gene transfer from wild relatives to cultivated crops that can overcome sexual incompatibilities of two distantly related species. In this study, interspecific asymmetric somatic hybrids of Brassica oleracea var. botrytis (cauliflower) and Brassica nigra (black mustard) were obtained by protoplast fusion and their backcrossed (BC(3)) and selfed (S(3)) offspring were analyzed. Cytological analysis showed that the B. nigra chromosomes were successively eliminated in the backcrosses with cauliflower. The fertility of the hybrid progenies was quite different due to the asynchronous and abnormal chromosome behavior of pollen mother cells (PMC) during meiosis. Analysis of sequence-related amplified polymorphism (SRAP) showed that all of these hybrids mainly had the DNA banding pattern from the two parents with some alterations. Genetically, the selfed generations were closer to B. nigra, while the backcrossed generations were closer to the cauliflower parent. Analysis of cleaved amplified polymorphic sequences (CAPS) and restriction fragment length polymorphisms (RFLP) showed that all somatic hybrids in this study contained chloroplast (cp) DNA of the donor parent black mustard, while mitochondrial (mt) DNA showed evidence of recombination and variations in the regions analyzed. Furthermore, three BC(3) plants (originated from somatic hybrids 3, 4, 10) with 2-8 B. nigra-derived chromosomes shown by genomic in situ hybridization (GISH) displayed a more cauliflower-like morphology and high resistance to black-rot. These plants were obtained as bridge materials for further analysis and breeding.

Assessment of genetic and epigenetic variation during long-term Taxus cell culture.

PubMed

Fu, Chunhua; Li, Liqin; Wu, Wenjuan; Li, Maoteng; Yu, Xiaoqing; Yu, Longjiang

2012-07-01

Gradual loss of secondary metabolite production is a common obstacle in the development of a large-scale plant cell production system. In this study, cell morphology, paclitaxel (Taxol®) biosynthetic ability, and genetic and epigenetic variations in the long-term culture of Taxus media cv Hicksii cells were assessed over a 5-year period to evaluate the mechanisms of the loss of secondary metabolites biosynthesis capacity in Taxus cell. The results revealed that morphological variations, gradual loss of paclitaxel yield and decreased transcriptional level of paclitaxel biosynthesis key genes occurred during long-term subculture. Genetic and epigenetic variations in these cultures were also studied at different times during culture using amplified fragment-length polymorphism (AFLP), methylation-sensitive amplified polymorphism (MSAP), and high-performance liquid chromatography (HPLC) analyses. A total of 32 primer combinations were used in AFLP amplification, and none of the AFLP loci were found to be polymorphic, thus no major genetic rearrangements were detected in any of the tested samples. However, results from both MSAP and HPLC indicated that there was a higher level of DNA methylation in the low-paclitaxel yielding cell line after long-term culture. Based on these results, we proposed that accumulation of paclitaxel in Taxus cell cultures might be regulated by DNA methylation. To our knowledge, this is the first report of increased methylation with the prolongation of culture time in Taxus cell culture. It provides substantial clues for exploring the gradual loss of the taxol biosynthesis capacity of Taxus cell lines during long-term subculture. DNA methylation maybe involved in the regulation of paclitaxel biosynthesis in Taxus cell culture.

[Polymorphism g.37190613 G>A of the ELMO1 gene in the Mexican population: potential marker for clinical-surgical pathology].

PubMed

Topete-González, Luz Rosalba; Ramirez-Garcia, Sergio Alberto; Charles-Niño, Claudia; Villa-Ruano, Nemesio; Mosso-González, Clemente; Dávalos-Rodríguez, Nory Omayra

2014-01-01

ELMO1 is a gene located at locus 7p14.2-14.1 that codifies a regulatory protein involved in fibrogenesis, cell migration, phagocytosis and apoptosis. This gene presents a single nucleotide polymorphism, which appears to be linked with the development of diabetic nephropathy. Currently, there are no studies in regard to the presence of such polymorphism in the Mexican population. Therefore, the aim of this work was to estimate the frequency rate of alleles and genotypes of polymorphism rs1345365 from ELMO1 in Mexican mestizos who inhabit the west and the southeast regions of Mexico in order to generate reliable data for further association studies. There were 322 individuals who were screened for the identification of polymorphism rs1345365 using genomic DNA from leucocytes as a template for PCR-PASA reactions. Amplicons were separated in 7% PAGE and visualized after staining with silver nitrate. The reference allele (A) was the most frequent in both western and southeastern populations of Mexico. In addition, a different genotype distribution was found with respect to other populations. The results of this study indicate that both populations are in Hardy-Weinberg equilibrium. This study also reveals a low frequency rate of the ancestral genotype for the polymorphism rs1345365 in mestizos from the western and southeastern regions of Mexico.

The contribution of DNA apurinic/apyrimidinic endonuclease genotype and smoking habit to Taiwan lung cancer risk.

PubMed

Chen, Wei-Chun; Tsai, Chia-Wen; Hsia, Te-Chun; Chang, Wen-Shin; Lin, Liang-Yi; Liang, Shinn-Jye; Tu, Chih-Yen; Cheng, Wei-Erh; Chen, Hung-Jen; Wang, Shu-Ming; Bau, da-Tian

2013-06-01

To evaluate the association and interaction of genotypic polymorphism the gene for DNA-apurinic/apyrimidinic endonuclease (APEX1) with personal smoking habit and lung cancer risk in Taiwan, the polymorphic variants of APEX1, Asp(148)Glu (rs1130409), were analyzed in association with lung cancer risk, and their joint effect with personal smoking habits on lung cancer susceptibility was discussed. In this hospital-based case-control study, 358 patients with lung cancer and 716 cancer-free controls, frequency-matched by age and sex, were recruited and genotyped by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The results showed that the percentages of TT, TG and GG APEX1 Asp(148)Glu genotypes were not significantly different at 43.0%, 41.1% and 15.9% in the lung cancer patient group and 39.9%, 46.1% and 14.0% in non-cancer control group, respectively. We further analyzed the genetic-lifestyle effects on lung cancer risk and found the contribution of APEX1 Asp(148)Glu genotypes to lung cancer susceptibility was neither enhanced in the cigarette smokers nor in the non-smokers (p=0.3550 and 0.8019, respectively). Our results provide evidence that the non-synonymous polymorphism of APEX1 Asp(148)Glu may not be directly associated with lung cancer risk, nor enhance the effects of smoking habit on lung cancer development.

[Using IRAP markers for analysis of genetic variability in populations of resource and rare species of plants].

PubMed

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.

DNA cards: determinants of DNA yield and quality in collecting genetic samples for pharmacogenetic studies.

PubMed

Mas, Sergi; Crescenti, Anna; Gassó, Patricia; Vidal-Taboada, Jose M; Lafuente, Amalia

2007-08-01

As pharmacogenetic studies frequently require establishment of DNA banks containing large cohorts with multi-centric designs, inexpensive methods for collecting and storing high-quality DNA are needed. The aims of this study were two-fold: to compare the amount and quality of DNA obtained from two different DNA cards (IsoCode Cards or FTA Classic Cards, Whatman plc, Brentford, Middlesex, UK); and to evaluate the effects of time and storage temperature, as well as the influence of anticoagulant ethylenediaminetetraacetic acid on the DNA elution procedure. The samples were genotyped by several methods typically used in pharmacogenetic studies: multiplex PCR, PCR-restriction fragment length polymorphism, single nucleotide primer extension, and allelic discrimination assay. In addition, they were amplified by whole genome amplification to increase genomic DNA mass. Time, storage temperature and ethylenediaminetetraacetic acid had no significant effects on either DNA card. This study reveals the importance of drying blood spots prior to isolation to avoid haemoglobin interference. Moreover, our results demonstrate that re-isolation protocols could be applied to increase the amount of DNA recovered. The samples analysed were accurately genotyped with all the methods examined herein. In conclusion, our study shows that both DNA cards, IsoCode Cards and FTA Classic Cards, facilitate genetic and pharmacogenetic testing for routine clinical practice.

Introducing Human Population Biology through an Easy Laboratory Exercise on Mitochondrial DNA

ERIC Educational Resources Information Center

Pardinas, Antonio F.; Dopico, Eduardo; Roca, Agustin; Garcia-Vazquez, Eva; Lopez, Belen

2010-01-01

This article describes an easy and cheap laboratory exercise for students to discover their own mitochondrial haplogroup. Students use buccal swabs to obtain mucosa cells as noninvasive tissue samples, extract DNA, and with a simple polymerase chain reaction-restriction fragment length polymorphism analysis they can obtain DNA fragments of…

Use PCR and a Single Hair To Produce a "DNA Fingerprint."

ERIC Educational Resources Information Center

Campbell, A. Malcolm; And Others

1997-01-01

Presents a laboratory procedure that involves students extracting their own DNA from a single hair follicle, using the polymerase chain reaction (PCR) to amplify a polymorphic locus, performing electrophoresis on the PCR products on an agarose gel, and visualizing the alleles to generate a "DNA fingerprint." Discusses theoretical background,…

Extracellular DNA in single- and multiple-species unsaturated biofilms.

PubMed

Steinberger, R E; Holden, P A

2005-09-01

The extracellular polymeric substances (EPS) of bacterial biofilms form a hydrated barrier between cells and their external environment. Better characterization of EPS could be useful in understanding biofilm physiology. The EPS are chemically complex, changing with both bacterial strain and culture conditions. Previously, we reported that Pseudomonas aeruginosa unsaturated biofilm EPS contains large amounts of extracellular DNA (eDNA) (R. E. Steinberger, A. R. Allen, H. G. Hansma, and P. A. Holden, Microb. Ecol. 43:416-423, 2002). Here, we investigated the compositional similarity of eDNA to cellular DNA, the relative quantity of eDNA, and the terminal restriction fragment length polymorphism (TRFLP) community profile of eDNA in multiple-species biofilms. By randomly amplified polymorphic DNA analysis, cellular DNA and eDNA appear identical for P. aeruginosa biofilms. Significantly more eDNA was produced in P. aeruginosa and Pseudomonas putida biofilms than in Rhodococcus erythropolis or Variovorax paradoxus biofilms. While the amount of eDNA in dual-species biofilms was of the same order of magnitude as that of of single-species biofilms, the amounts were not predictable from single-strain measurements. By the Shannon diversity index and principle components analysis of TRFLP profiles generated from 16S rRNA genes, eDNA of four-species biofilms differed significantly from either cellular or total DNA of the same biofilm. However, total DNA- and cellular DNA-based TRFLP analyses of this biofilm community yielded identical results. We conclude that extracellular DNA production in unsaturated biofilms is species dependent and that the phylogenetic information contained in this DNA pool is quantifiable and distinct from either total or cellular DNA.

Association between AMELX polymorphisms and dental caries in Koreans.

PubMed

Kang, S W; Yoon, I; Lee, H W; Cho, J

2011-05-01

Dental caries is greatly influenced disease by environmental factors, but recently there are increasing evidences for a genetic component in caries susceptibility. AMELX is the gene coding amelogenin, which is the most important factor for normal enamel development. The aim of this study was to examine the relationship between dental caries and single nucleotide polymorphisms (SNPs) in AMELX. For this study, we used DNA samples collected from 120 unrelated individuals older than 12 years of age. All of them were examined for their oral and dental status under the WHO recommended criteria, and clinical information such as DMFT and DMFS were evaluated. Individuals whose DMFT and DMFS index lower than 2 were designated 'very low caries experience' and higher than 3 were designated 'higher caries experience'. Genomic DNA was extracted from hair samples, and single nucleotide polymorphisms of AMELX were genotyped. Genotyping of three SNPs (rs17878486, rs5933871, rs5934997, intron) in AMELX gene was determined by direct sequencing and analyzed with SNPStats. There were significant associations between rs5933871 and rs5934997 SNP and caries susceptibility in the water fluoridation group. These results suggest that SNPs of AMELX might be associated with dental caries susceptibility in Korean population. © 2010 John Wiley & Sons A/S.

Genome-wide DNA polymorphisms in Kavuni, a traditional rice cultivar with nutritional and therapeutic properties.

PubMed

Rathinasabapathi, Pasupathi; Purushothaman, Natarajan; Parani, Madasamy

2016-05-01

Although rice genome was sequenced in the year 2002, efforts in resequencing the large number of available accessions, landraces, traditional cultivars, and improved varieties of this important food crop are limited. We have initiated resequencing of the traditional cultivars from India. Kavuni is an important traditional rice cultivar from South India that attracts premium price for its nutritional and therapeutic properties. Whole-genome sequencing of Kavuni using Illumina platform and SNPs analysis using Nipponbare reference genome identified 1 150 711 SNPs of which 377 381 SNPs were located in the genic regions. Non-synonymous SNPs (62 708) were distributed in 19 251 genes, and their number varied between 1 and 115 per gene. Large-effect DNA polymorphisms (7769) were present in 3475 genes. Pathway mapping of these polymorphisms revealed the involvement of genes related to carbohydrate metabolism, translation, protein-folding, and cell death. Analysis of the starch biosynthesis related genes revealed that the granule-bound starch synthase I gene had T/G SNPs at the first intron/exon junction and a two-nucleotide combination, which were reported to favour high amylose content and low glycemic index. The present study provided a valuable genomics resource to study the rice varieties with nutritional and medicinal properties.

Epigenetic Variability in the Genetically Uniform Forest Tree Species Pinus pinea L

PubMed Central

Sáez-Laguna, Enrique; Guevara, María-Ángeles; Díaz, Luis-Manuel; Sánchez-Gómez, David; Collada, Carmen; Aranda, Ismael; Cervera, María-Teresa

2014-01-01

There is an increasing interest in understanding the role of epigenetic variability in forest species and how it may contribute to their rapid adaptation to changing environments. In this study we have conducted a genome-wide analysis of cytosine methylation pattern in Pinus pinea, a species characterized by very low levels of genetic variation and a remarkable degree of phenotypic plasticity. DNA methylation profiles of different vegetatively propagated trees from representative natural Spanish populations of P. pinea were analyzed with the Methylation Sensitive Amplified Polymorphism (MSAP) technique. A high degree of cytosine methylation was detected (64.36% of all scored DNA fragments). Furthermore, high levels of epigenetic variation were observed among the studied individuals. This high epigenetic variation found in P. pinea contrasted with the lack of genetic variation based on Amplified Fragment Length Polymorphism (AFLP) data. In this manner, variable epigenetic markers clearly discriminate individuals and differentiates two well represented populations while the lack of genetic variation revealed with the AFLP markers fail to differentiate at both, individual or population levels. In addition, the use of different replicated trees allowed identifying common polymorphic methylation sensitive MSAP markers among replicates of a given propagated tree. This set of MSAPs allowed discrimination of the 70% of the analyzed trees. PMID:25084460

Epigenetic variability in the genetically uniform forest tree species Pinus pinea L.

PubMed

Sáez-Laguna, Enrique; Guevara, María-Ángeles; Díaz, Luis-Manuel; Sánchez-Gómez, David; Collada, Carmen; Aranda, Ismael; Cervera, María-Teresa

2014-01-01

There is an increasing interest in understanding the role of epigenetic variability in forest species and how it may contribute to their rapid adaptation to changing environments. In this study we have conducted a genome-wide analysis of cytosine methylation pattern in Pinus pinea, a species characterized by very low levels of genetic variation and a remarkable degree of phenotypic plasticity. DNA methylation profiles of different vegetatively propagated trees from representative natural Spanish populations of P. pinea were analyzed with the Methylation Sensitive Amplified Polymorphism (MSAP) technique. A high degree of cytosine methylation was detected (64.36% of all scored DNA fragments). Furthermore, high levels of epigenetic variation were observed among the studied individuals. This high epigenetic variation found in P. pinea contrasted with the lack of genetic variation based on Amplified Fragment Length Polymorphism (AFLP) data. In this manner, variable epigenetic markers clearly discriminate individuals and differentiates two well represented populations while the lack of genetic variation revealed with the AFLP markers fail to differentiate at both, individual or population levels. In addition, the use of different replicated trees allowed identifying common polymorphic methylation sensitive MSAP markers among replicates of a given propagated tree. This set of MSAPs allowed discrimination of the 70% of the analyzed trees.

Genetic and epigenetic stability of cryopreserved and cold-stored hops (Humulus lupulus L.).

PubMed

Peredo, Elena L; Arroyo-García, Rosa; Reed, Barbara M; Revilla, M Angeles

2008-12-01

Conventional cold storage and cryopreservation methods for hops (Humulus lupulus L.) are available but, to our knowledge, the genetic and epigenetic stability of the recovered plants have not been tested. This study analyzed 51 accessions of hop using the molecular techniques, Random Amplified DNA Polymorphism (RAPD) and Amplified Fragment Length Polymorphism (AFLP), revealing no genetic variation among greenhouse-grown controls and cold stored or cryopreserved plants. Epigenetic stability was evaluated using Methylation Sensitive Amplified Polymorphism (MSAP). Over 36% of the loci were polymorphic when the cold and cryo-treated plants were compared to greenhouse plants. The main changes were demethylation events and they were common to the cryopreserved and cold stored plants indicating the possible effect of the in vitro establishment process, an essential step in both protocols. Protocol-specific methylation patterns were also detected indicating that both methods produced epigenetic changes in plants following cold storage and cryopreservation.

Single Nucleotide Polymorphism in ATM Gene, Cooking Oil Fumes and Lung Adenocarcinoma Susceptibility in Chinese Female Non-Smokers: A Case-Control Study

PubMed Central

Shen, Li; Yin, Zhihua; Wu, Wei; Ren, Yangwu; Li, Xuelian; Zhou, Baosen

2014-01-01

Background The ataxia-telangiectasia mutated (ATM) gene plays an important role in the DNA double-strand breaks repair pathway. Single nucleotide polymorphisms (SNPs) of DNA repair genes are suspected to influence the risk of lung cancer. This study aimed to investigate the association between the ATM -111G>A (rs189037) polymorphism, environmental risk factors and the risk of lung adenocarcinoma in Chinese female non-smokers. Methods A hospital-based case-control study of 487 lung cancer patients and 516 matched cancer-free controls was conducted. Information concerning demographic and environmental risk factors was obtained for each case and control by a trained interviewer. After informed consent was obtained, 10 ml venous blood was collected from each subject for biomarker testing. Single nucleotide polymorphism was determined by using TaqMan method. Results This study showed that the individuals with ATM rs189037 AA genotype were at an increased risk for lung adenocarcinoma compared with those carrying the GA or GG genotype (adjusted odds ratios (OR) 1.44, 95% confidence interval (CI) 1.02–2.02, P = 0.039). The stratified analysis suggested that increased risk associated with ATM rs189037 AA genotype in individuals who never or seldom were exposed to cooking oil fumes (adjusted OR 1.89, 95%CI 1.03–3.49, P = 0.040). Conclusions ATM rs189037 might be associated with the risk of lung adenocarcinoma in Chinese non-smoking females. Furthermore, ATM rs189037 AA genotype might be a risk factor of lung adenocarcinoma among female non-smokers without cooking oil fume exposure. PMID:24819391