scholarly journals The Genetic Diversity and Structure of Linkage Disequilibrium of the MTHFR Gene in Populations of Northern Eurasia

Acta Naturae ◽  
2012 ◽  
Vol 4 (1) ◽  
pp. 53-69 ◽  
Author(s):  
E. A. Trifonova ◽  
E. R. Eremina ◽  
F. D. Urnov ◽  
V. A. Stepanov
Keyword(s):  
Linkage Disequilibrium ◽  
Methylenetetrahydrofolate Reductase ◽  
Prognostic Significance ◽  
Complex Diseases ◽  
Mthfr Gene ◽  
Biomedical Science ◽  
Northern Eurasia ◽  
Human Populations ◽  
International Hapmap Project ◽  
Genetic Diversity And Structure

The structure of the haplotypes and linkage disequilibrium (LD) of the methylenetetrahydrofolate reductase gene (MTHFR) in 9 population groups from Northern Eurasia and populations of the international HapMap project was investigated in the present study. The data suggest that the architecture of LD in the human genome is largely determined by the evolutionary history of populations; however, the results of phylogenetic and haplotype analyses seems to suggest that in fact there may be a common old mechanism for the formation of certain patterns of LD. Variability in the structure of LD and the level of diversity of MTHFR haplotypes cause a certain set of tagSNPs with an established prognostic significance for each population. In our opinion, the results obtained in the present study are of considerable interest for understanding multiple genetic phenomena: namely, the association of interpopulation differences in the patterns of LD with structures possessing a genetic susceptibility to complex diseases, and the functional significance of the pleiotropic MTHFR gene effect. Summarizing the results of this study, a conclusion can be made that the genetic variability analysis with emphasis on the structure of LD in human populations is a powerful tool that can make a significant contribution to such areas of biomedical science as human evolutionary biology, functional genomics, genetics of complex diseases, and pharmacogenomics.

Analysis of the 677 C→T Mutation of the Methylenetetrahydrofolate Reductase Gene in Different Ethnic Groups

1998 ◽  
Vol 79 (01) ◽  
pp. 119-121 ◽  
Author(s):  
R. F. Franco ◽  
A. G. Araújo ◽  
J. F. Guerreiro ◽  
J. Elion ◽  
M. A. Zago
Keyword(s):  
Ethnic Groups ◽  
Racial Differences ◽  
Methylenetetrahydrofolate Reductase ◽  
Mthfr Gene ◽  
Human Populations ◽  
Heterogeneous Distribution ◽  
Positive Allele ◽  
Increased Risk ◽  
Reductase Gene ◽  
Low Prevalence

SummaryA recently described mutation in the methylenetetrahydrofolate reductase (MTHFR) gene (a C to T transition at nucleotide 677) is associated with a thermolabile phenotype and decreased enzyme activity. In homozygotes, the mutation is also related to hyperhomocysteinemia and increased risk for atherosclerotic disease and (apparently) venous thrombosis. The prevalence of this mutation in different human populations is unknown. We have investigated the frequency of the 677 C→T mutation in the MTHFR gene in 337 individuals (674 chromosomes) belonging to four ethnic groups: Whites, African and Brazilian Blacks, Asians and Amerindians. The frequencies of the positive allele among Whites and Asians were similar to those previously reported for Caucasian populations. The positive allele seems to be slightly rarer among the Amerindians (frequency 24.0%) in comparison to Whites and Asians, with a heterogeneous distribution among the five Indian tribes analysed. In contrast, the mutation has a very low prevalence in Blacks, especially among the African Blacks, for whom the mutation was absent in homozygosity. Our data indicate that the 677 C→T MTHFR mutation has a significantly heterogeneous distribution among different ethnic groups, a fact that may contribute to explain geographical or racial differences in the risk for vascular disease.

Multilocus Analysis of Genetic Susceptibility to Myocardial Infarction in Russians: Replication Study

Acta Naturae ◽  
2017 ◽  
Vol 9 (4) ◽  
pp. 74-83
Author(s):  
N. G. Kukava ◽  
B. V. Titov ◽  
G. J. Osmak ◽  
N. A. Matveeva ◽  
O. G. Kulakova ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Genetic Markers ◽  
Prognostic Significance ◽  
Cumulative Effect ◽  
Mthfr Gene ◽  
Composite Model ◽  
Replication Study ◽  
Epistatic Interactions ◽  
Multilocus Analysis ◽  
Lipid Metabolism Genes

In search of genetic markers of myocardial infarction (MI) risk, which have prognostic significance for Russians, we performed a replication study of MI association with genetic variants of PCSK9 (rs562556), APOE (epsilon polymorphism, rs7412 and rs429358), LPL (rs320), MTHFR (rs1801133), eNOS (rs2070744), and the 9p21 region (rs1333049) in 405 patients with MI and 198 controls. Significant MI association was observed with variants of the lipid metabolism genes (PCSK9, APOE and LPL), and of eNOS. The SNPs in the MTHFR gene and the 9p21 region were not significantly associated with MI one by one but were included in several different MI-associated allelic combinations identified by multilocus analysis. Since we have not revealed nonlinear epistatic interactions between the components of the identified combinations, we postulate that the cumulative effect of genes that form a combination arises from the summation of their small independent contributions. The prognostic significance of the additive composite model built from the PCSK9, APOE, LPL, and eNOS genes as genetic markers was assessed using ROC analysis. After we included these markers in the previously published composite model of individual genetic risk of MI, the prognostic efficacy in our sample reached AUC = 0.676. However, the results obtained in this study certainly need to be replicated in an independent sample of Russians.

Methylenetetrahydrofolate reductase polymorphisms as risk factors for retinal venous occlusive disease: A literature review

2021 ◽  
pp. 112067212110006
Author(s):  
Manuel Marques ◽  
Francisco Alves ◽  
Miguel Leitão ◽  
Catarina Rodrigues ◽  
Joana Tavares Ferreira
Keyword(s):  
Risk Factors ◽  
Literature Review ◽  
Methylenetetrahydrofolate Reductase ◽  
Mthfr C677t ◽  
Mthfr Gene ◽  
Mthfr Polymorphisms ◽  
Vein Occlusion ◽  
C677t Mutation ◽  
Retinal Vascular Disease

The role of polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene in retinal vein occlusion (RVO) is a theme of discussion since the first reports of RVO in patients with MTHFR C677T mutation and without classic acquired risk factors for retinal vascular disease. The association between MTHFR polymorphisms and RVO has been studied over the last 20 years producing conflicting results. This review aims to summarize the literature concerning the role MTHFR polymorphisms as risk factors for RVO.

scholarly journals COVID‐19 spreading across world correlates with C677T allele of the methylenetetrahydrofolate reductase (MTHFR) gene prevalence

2021 ◽  
Author(s):  
Giovanni Ponti ◽  
Lorenza Pastorino ◽  
Marco Manfredini ◽  
Tomris Ozben ◽  
Gabriella Oliva ◽  
...  
Keyword(s):  
Methylenetetrahydrofolate Reductase ◽  
Mthfr Gene

Correlation between Methylenetetrahydrofolate Reductase Polymorphisms and Hepatocellular Carcinoma: A Meta-Analysis

2019 ◽  
Vol 74 (3) ◽  
pp. 251-256 ◽  
Author(s):  
Hailong Su ◽  
Guo Zhang
Keyword(s):  
Hepatocellular Carcinoma ◽  
Gene Polymorphisms ◽  
Methylenetetrahydrofolate Reductase ◽  
Meta Analysis ◽  
Random Effect ◽  
Recessive Model ◽  
Mthfr Gene ◽  
Systematic Research ◽  
The Relationship ◽  
Random Effect Models

Background: The correlation between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and hepatocellular carcinoma (HCC) remains controversial. Objectives: We performed this study to better assess the relationship between MTHFR gene polymorphisms and the likelihood of HCC. Methods: A systematic research of PubMed, Medline, and Embase was performed to retrieve relevant articles. ORs and 95% CIs were calculated. Results: A total of 15 studies with 8,378 participants were analyzed. In overall analyses, a significant association with the likelihood of HCC was detected for the rs1801131 polymorphism with fixed-effect models (FEMs) in recessive comparison (p = 0.002, OR 0.62, 95% CI 0.43–0.82). However, no positive results were detected for the rs1801133 polymorphism in any comparison. Further subgroup analyses revealed that the rs1801131 polymorphism was significantly associated with the likelihood of HCC in Asians with both FEMs (recessive model: p < 0.0001, OR 0.42, 95% CI 0.29–0.62; allele model: p = 0.004, OR 1.20, 95% CI 1.06–1.35) and random-effect models (recessive model: p = 0.002, OR 0.47, 95% CI 0.29–0.75). Nevertheless, we failed to detect any significant correlation between the rs1801133 polymorphism and HCC. Conclusions: Our findings indicated that the rs1801131 polymorphism may serve as a genetic biomarker of HCC in Asians.

MTHFR 677T-1298C haplotype in acute lymphoblastic leukemia: Impact on methotrexate therapy

2021 ◽  
pp. 107815522110171
Author(s):  
Rim Frikha ◽  
Moez Elloumi ◽  
Tarek Rebai ◽  
Hassen Kamoun
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Methylenetetrahydrofolate Reductase ◽  
Fragment Length Polymorphism ◽  
Lymphoblastic Leukemia ◽  
Allelic Frequency ◽  
Mthfr Gene ◽  
Methotrexate Therapy ◽  
Wild Type ◽  
Functional Variants ◽  
Toxicity Score

Introduction Functional variants of the Methylenetetrahydrofolate reductase ( MTHFR) gene, the C677T and A1298C, have largely investigated in pharmacogenomics of Methotrexate (MTX) in acute lymphoblastic leukemia (ALL), yet the conclusions are inconsistent. In addition; most of these studies do not analyze haplotypes. Here, we investigate the MTHFR 677/1298 genotypes and the 677-1298 haplotype and characterize the MTX response in Northern African ALL patients. Methods Genomic DNA was extracted from whole venous from a total of 28 patients with ALL. Genotyping were carried out with restriction fragment length polymorphism (RFLP). A toxicity score (TS) is calculated for each patient and correlate to the haplotype. Results The allelic frequency of MTHFR 677T-1298C haplotype was 10.7% in ALL patients. According to the toxicity’s score (TS) there was no significant differences between haplotype groups (p = 0.79): TS was higher with wild type of MTHFR (TS = 3.43; SEM ± 0.85) followed by combined genotype (677T-1298C) (TS = 2.67; SEM ± 0.88) and isolated variant (C677T or A1298C) (TS = 2.64; SEM ± 0.92). Conclusion Despite the limitation of this study; our results suggest that the MTHFR 677T-1298C haplotype is common in ALL and may be a promising HD-MTX chemotherapy-related adverse effects biomarker.

Ethnic Differences in the Frequency of the C677T Mutation in the Methylenetetrahydrofolate Reductase (MTHFR) Gene in Healthy Israeli Populations

2000 ◽  
Vol 4 (3) ◽  
pp. 309-311 ◽  
Author(s):  
Rivka Dresner Pollak ◽  
Yechiel Friedlander ◽  
Arthur Pollak ◽  
Maria Idelson ◽  
Idit Bejarano-Achache ◽  
...  
Keyword(s):  
Ethnic Differences ◽  
Methylenetetrahydrofolate Reductase ◽  
Mthfr Gene ◽  
C677t Mutation

scholarly journals Is MTHFR polymorphism a risk factor for Alzheimer's disease like APOE?

2005 ◽  
Vol 63 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Liana Lisboa Fernandez ◽  
Rosane Machado Scheibe
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Risk Factor ◽  
Methylenetetrahydrofolate Reductase ◽  
Venous Blood ◽  
Dna Amplification ◽  
Mthfr Gene ◽  
Chi Square ◽  
Mthfr Polymorphism ◽  
Significant Difference

BACKGROUND: The role of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms as risk factors for the occurence of Alzheimer's disease (AD) is still controversial: OBJECTIVE: To verify the association between MTHFR and apolipoprotein E (APOE) polymorphisms and Alzheimer's disease. METHOD: This work was conducted as a case-control study. Cases included thirty patients with probable AD. Controls were constituted by 29 individuals without dementia according to neuropsychological tests paired to age, sex, race and educational level. DNA was isolated from peripheral leukocytes of anticoagulated venous blood. Genotyping of APOE and MTHFR were performed by DNA amplification and digestion. The frequences of APOE and MTHFR genotypes were submitted by chi-square test corrected by Fisher test; the APOE genotypes, to chi-square linear tendency test and the frequences of MTHFR mutant and AD, by stratificated anlysis adjust by Mantel-Haenszel method. RESULTS: There was significant difference about APOE4 and APOE2 in the groups. (p=0.002) The odds ratio increased exponentially with the increased number of E4 allele (chi2 linear tendency test). No significant difference was detected on MTHFR genotypes in both case and control groups. CONCLUSION: The APOE4 is a risk factor and demonstrated a dose-depenent effect while APOE2 allele conferred a protection to AD. The MTHFR mutation had no correlation with AD.

scholarly journals Should MTHFR 1298 A>C be tested together with MTHFR 677 C>T polymorphism in women with reproductive challenges?

Genetika ◽  
2017 ◽  
Vol 49 (2) ◽  
pp. 377-386
Author(s):  
Jelena Djurovic ◽  
Oliver Stojkovic ◽  
Jelena Todorovic ◽  
Kristina Savic ◽  
Gorana Stamenkovic
Keyword(s):  
Genomic Dna ◽  
Methylenetetrahydrofolate Reductase ◽  
Critical Role ◽  
Mthfr Gene ◽  
Elevated Risk ◽  
Similar Frequency ◽  
Mthfr Polymorphisms ◽  
Healthy Female ◽  
Healthy Control ◽  
Associated Conditions

Methylenetetrahydrofolate reductase (MTHFR) plays a critical role in the folate metabolism. The polymorphism 677C>T of the MTHFR gene, producing thermolabile enzyme with decreased function, is widely studied and associated with many conditions. Additionally, it has been shown that another polymorphism, 1298A>C, also reduces the activity of this enzyme, although to a lesser extent. The aim of this study is to evaluate the clinical informativeness of testing both MTHFR polymorphisms. Genomic DNA, were extracted from peripheral blood of 180 female patients with pregnancy complications and 183 healthy female controls, and genotyped for MTHFR 677C>T and 1298A>C loci, using TaqMan assays. Our study found similar frequency of alleles and genotypes between two groups. Based on MTHFR 677C>T genotype, 11.7% of patients homozygous for this mutation were under the possible risk. When the position 1298 was included in the testing, 22.8% of the patients were heterozygous for both polymorphisms. Additionally, 8.9% of the patients were homozygous only for the MTHFR 1298 mutation. Although,s there was no differences compared to healthy control (p>0.05), 43% of patients were found to have elevated risk which is about four time highers than results with only MTHFR 677C>T genotyping. After obtaining information for the 677 position, testing for the second polymorphism (1298A>C) should be considered, since we have shown that it dramatically increases the rate of detection of patients who are potentially at risk for MTHFR associated conditions.

scholarly journals Forward-time Simulations of Human Populations with Complex Diseases

PLoS Genetics ◽  
2005 ◽  
Vol preprint (2007) ◽  
pp. e47
Author(s):  
Bo Peng ◽  
Christopher Amos ◽  
Marek Kimmel
Keyword(s):  
Complex Diseases ◽  
Human Populations
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