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Sample records for methylenetetrahydrofolate reductase polymorphisms

  1. Methylenetetrahydrofolate Reductase gene polymorphism in children with allergic rhinitis.

    PubMed

    Dogru, M; Aydin, H; Aktas, A; Cırık, A A

    2015-01-01

    Methylenetetrahydrofolate Reductase (MTHFR) polymorphisms by impairing folate metabolism may influence the development of allergic diseases. The results of studies evaluating the relationship between MTHFR polymorphisms and atopic disease are controversial. The aim of this study was to investigate the association between the polymorphisms of C677T and A1298C for MTHFR gene and allergic rhinitis (AR) in children. Ninety patients followed up with diagnosis of allergic rhinitis in our clinic and 30 children with no allergic diseases were included in the study. All participants were genotyped for the MTHFR (C677T) and (A1298C) polymorphisms. Vitamin b12, folate and homocysteine levels were measured. The mean age of patients was 9.2±2.9 years; 66.7% of the patients were male. There was no significant difference between patient and control groups regarding gender, age and atopy history of the family (p>0.05). The frequency of homozygotes for MTHFR C677T polymorphism in the patient and control groups was 3.3% and 10%, respectively. The frequency of homozygotes for MTHFR A1298C polymorphism among groups was 26.7% and 16.7%, respectively. The association between allergic rhinitis and polymorphisms of C677T and A1298C for MTHFR gene was not statistically significant in patients compared with controls (p>0.05). There were no statistically significant differences between the patients and the control group in terms of serum vitamin b12, folate and homocysteine levels (p>0.05). We found no evidence for an association between allergic rhinitis and polymorphisms of C677T and A1298C for MTHFR gene in children. Further studies investigating the relationship between MTHFR polymorphism and AR are required. Copyright © 2014 SEICAP. Published by Elsevier Espana. All rights reserved.

  2. Prognostic Relevance of Methylenetetrahydrofolate Reductase Polymorphisms for Prostate Cancer

    PubMed Central

    Lin, Victor C.; Lu, Te-Ling; Yin, Hsin-Ling; Yang, Sheau-Fang; Lee, Yung-Chin; Liu, Chia-Chu; Huang, Chao-Yuan; Yu, Chia-Cheng; Chang, Ta-Yuan; Huang, Shu-Pin; Bao, Bo-Ying

    2016-01-01

    Folate metabolism has been associated with cancers via alterations in nucleotide synthesis, DNA methylation, and DNA repair. We hypothesized that genetic variants in methylenetetrahydrofolate reductase (MTHFR), a key enzyme of folate metabolism, would affect the prognosis of prostate cancer. Three haplotype-tagging single-nucleotide polymorphisms (SNPs) across the MTHFR gene region were genotyped in a cohort of 458 patients with clinically localized prostate cancer treated with radical prostatectomy. One SNP, rs9651118, was associated with disease recurrence, and the association persisted after multivariate analyses adjusting for known risk factors. Public dataset analyses suggested that rs9651118 affects MTHFR expression. Quantitative real-time polymerase chain reaction analysis revealed that MTHFR expression is significantly upregulated in prostate tumor tissues when compared with adjacent normal tissues. Furthermore, overexpression of MTHFR correlates with cancer recurrence and death in two independent publicly available prostate cancer datasets. In conclusion, our data provide rationale to further validate the clinical utility of MTHFR rs9651118 as a biomarker for prognosis in prostate cancer. PMID:27916838

  3. Prognostic Relevance of Methylenetetrahydrofolate Reductase Polymorphisms for Prostate Cancer.

    PubMed

    Lin, Victor C; Lu, Te-Ling; Yin, Hsin-Ling; Yang, Sheau-Fang; Lee, Yung-Chin; Liu, Chia-Chu; Huang, Chao-Yuan; Yu, Chia-Cheng; Chang, Ta-Yuan; Huang, Shu-Pin; Bao, Bo-Ying

    2016-11-29

    Folate metabolism has been associated with cancers via alterations in nucleotide synthesis, DNA methylation, and DNA repair. We hypothesized that genetic variants in methylenetetrahydrofolate reductase (MTHFR), a key enzyme of folate metabolism, would affect the prognosis of prostate cancer. Three haplotype-tagging single-nucleotide polymorphisms (SNPs) across the MTHFR gene region were genotyped in a cohort of 458 patients with clinically localized prostate cancer treated with radical prostatectomy. One SNP, rs9651118, was associated with disease recurrence, and the association persisted after multivariate analyses adjusting for known risk factors. Public dataset analyses suggested that rs9651118 affects MTHFR expression. Quantitative real-time polymerase chain reaction analysis revealed that MTHFR expression is significantly upregulated in prostate tumor tissues when compared with adjacent normal tissues. Furthermore, overexpression of MTHFR correlates with cancer recurrence and death in two independent publicly available prostate cancer datasets. In conclusion, our data provide rationale to further validate the clinical utility of MTHFR rs9651118 as a biomarker for prognosis in prostate cancer.

  4. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in psoriasis in southern Turkey.

    PubMed

    Izmirli, Muzeyyen; Sen, Bilge Bulbul; Rifaioglu, Eminenur; Gogebakan, Bulent; Aldemir, Ozgur; Sen, Tuba; Ekiz, Ozlem; Alptekin, Davut

    2016-01-01

    Psoriasis is a multigenic and multifactorial dermatological disease linked to cardiovascular diseases. Increased levels of homocysteine in patients with psoriasis have been demonstrated in many studies. The most frequently investigated genetic defect that plays a role in homocysteine metabolism is single point substitution (C to T) located on the 677th nucleotide of the methylenetetrahydrofolate reductase gene (MTHFR). In this study, we aimed to investigate methylenetetrahydrofolate C677T polymorphism in psoriasis patients in Turkey. The study included 96 patients with psoriasis and 77 controls from southern Turkey. Methylenetetrahydrofolate C677T polymorphism was analysed using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism methods. In the psoriasis group, 34 CC (35.4%), 46 CT (47.9%) and 16 TT (16.7%) genotypes were found, respectively; while in the control group, the figures were 39 (50.6%), 35 (45.5%), 3 (3.9%). Homozygote and heterozygote T alleles of methylenetetrahydrofolate C677T polymorphism were significantly higher in the psoriasis than in the control group (p=0.013). We firstly found a correlation between methylenetetrahydrofolate C677T polymorphism and psoriasis among the southern Turkish population.

  5. [Methylenetetrahydrofolate reductase and methionine synthase reductase gene polymorphisms in ethnic Han women from Linyi].

    PubMed

    Zhang, Yan-li; Lu, Yan-qiang; Li, Hua-feng; Rui, Xin-yi; Zhang, Li-jun; Wu, Chuan-ye; Fang, Ai-min; Wang, Gui-xi

    2012-12-01

    To explore the distribution of genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) 677C/T, 1298A/C and methionine synthase reductase (MTRR) 66A/G among ethnic Han females from Linyi, and to correlate it with serum level of homocysteine (Hcy). A cross-sectional study was carried out. Oral epithelial cell samples were collected from 825 subjects. MTHFR and MTRR gene polymorphisms were determined with a Taqman-Minor Groove Binder (MGB) method. Distribution of gene polymorphisms was analyzed and compared with others regions of China including Weifang, Zhengzhou, Deyang and Hainan. A biochemical assay was also carried out to determine the total Hcy in plasma of 281 subjects. The reductase activity of MTHFR was classified into decreased and stable groups according to genetic polymorphism of MTHFR. Correlation between MTHFR groups and total Hcy level were also explored. (1) The frequencies of MTHFR677CC, CT and TT genotypes of the selected subjects were 16.7%, 48.3% and 35.0%, respectively. The frequencies of MTHFR 1298AA, AC and CC genotypes were 76.0%, 21.6% and 2.4%, respectively. And those of MTRR 66AA, AG and GG genotypes were 54.7%, 39.4% and 5.9%, respectively. For the selected subjects, their frequency of MTHFR 677TT genotype was higher than that of Deyang and Hainan (P< 0.01), whilst the frequency of MTHFR 1298CC genotype was lower than that of Deyang and Hainan (P < 0.01), and the frequency of MTRR 66 GG genotype was lower than that of Hainan (P< 0.01). (2) The Hcy level for those with decreased MTHFR activity was significantly higher than those with stable MTHFR activity (P< 0.05). MTHFR gene 677C/T, 1298A/C and MTRR 66A/G polymorphisms in ethnic Han women from Linyi have differed significantly from other regions of China. Decreased MTHFR activity caused by genetic polymorphisms is a risk factor for raised Hcy level.

  6. [Alzheimer's disease and methylenetetrahydrofolate reductase gene polymorphisms: a potential nutrigenomic approach for Mexico].

    PubMed

    Castillo-Quan, Jorge I; Pérez-Osorio, Julia M

    2009-01-01

    The establishment of medical genomics in Mexico offers the possibility to study in a more comprehensive manner the etiological factors of different diseases, providing a global view of the interaction between the genome and the environment. Nutrition is recognized as a significant determinant in several diseases, yet its interaction with polymorphisms, and in general with the genome, has not been properly addressed Mexico has a high prevalence of polymorphisms of the methylenetetrahydrofolate reductase gene, and in both clinical and basic studies this has been associated with an increased susceptibility of developing Alzheimer's disease. We propose a potential nutrigenomic approach for the study of Alzheimer disease in Mexico.

  7. The polymorphisms in methylenetetrahydrofolate reductase, methionine synthase, methionine synthase reductase, and the risk of colorectal cancer.

    PubMed

    Zhou, Daijun; Mei, Qiang; Luo, Han; Tang, Bo; Yu, Peiwu

    2012-01-01

    Polymorphisms in genes involved in folate metabolism may modulate the risk of colorectal cancer (CRC), but data from published studies are conflicting. The current meta-analysis was performed to address a more accurate estimation. A total of 41 (17,552 cases and 26,238 controls), 24(8,263 cases and 12,033 controls), 12(3,758 cases and 5,646 controls), and 13 (5,511 cases and 7,265 controls) studies were finally included for the association between methylenetetrahydrofolate reductase (MTHFR) C677T and A1289C, methione synthase reductase (MTRR) A66G, methionine synthase (MTR) A2756G polymorphisms and the risk of CRC, respectively. The data showed that the MTHFR 677T allele was significantly associated with reduced risk of CRC (OR = 0.93, 95%CI 0.90-0.96), while the MTRR 66G allele was significantly associated with increased risk of CRC (OR = 1.11, 95%CI 1.01-1.18). Sub-group analysis by ethnicity revealed that MTHFR C677T polymorphism was significantly associated with reduced risk of CRC in Asians (OR = 0.80, 95%CI 0.72-0.89) and Caucasians (OR = 0.84, 95%CI 0.76-0.93) in recessive genetic model, while the MTRR 66GG genotype was found to significantly increase the risk of CRC in Caucasians (GG vs. AA: OR = 1.18, 95%CI 1.03-1.36). No significant association was found between MTHFR A1298C and MTR A2756G polymorphisms and the risk of CRC. Cumulative meta-analysis showed no particular time trend existed in the summary estimate. Probability of publication bias was low across all comparisons illustrated by the funnel plots and Egger's test. Collectively, this meta-analysis suggested that MTHFR 677T allele might provide protection against CRC in worldwide populations, while MTRR 66G allele might increase the risk of CRC in Caucasians. Since potential confounders could not be ruled out completely, further studies were needed to confirm these results.

  8. The Polymorphisms in Methylenetetrahydrofolate Reductase, Methionine Synthase, Methionine Synthase Reductase, and the Risk of Colorectal Cancer

    PubMed Central

    Zhou, Daijun; Mei, Qiang; Luo, Han; Tang, Bo; Yu, Peiwu

    2012-01-01

    Polymorphisms in genes involved in folate metabolism may modulate the risk of colorectal cancer (CRC), but data from published studies are conflicting. The current meta-analysis was performed to address a more accurate estimation. A total of 41 (17,552 cases and 26,238 controls), 24(8,263 cases and 12,033 controls), 12(3,758 cases and 5,646 controls), and 13 (5,511 cases and 7,265 controls) studies were finally included for the association between methylenetetrahydrofolate reductase (MTHFR) C677T and A1289C, methione synthase reductase (MTRR) A66G, methionine synthase (MTR) A2756G polymorphisms and the risk of CRC, respectively. The data showed that the MTHFR 677T allele was significantly associated with reduced risk of CRC (OR = 0.93, 95%CI 0.90-0.96), while the MTRR 66G allele was significantly associated with increased risk of CRC (OR = 1.11, 95%CI 1.01-1.18). Sub-group analysis by ethnicity revealed that MTHFR C677T polymorphism was significantly associated with reduced risk of CRC in Asians (OR = 0.80, 95%CI 0.72-0.89) and Caucasians (OR = 0.84, 95%CI 0.76-0.93) in recessive genetic model, while the MTRR 66GG genotype was found to significantly increase the risk of CRC in Caucasians (GG vs. AA: OR = 1.18, 95%CI 1.03-1.36). No significant association was found between MTHFR A1298C and MTR A2756G polymorphisms and the risk of CRC. Cumulative meta-analysis showed no particular time trend existed in the summary estimate. Probability of publication bias was low across all comparisons illustrated by the funnel plots and Egger's test. Collectively, this meta-analysis suggested that MTHFR 677T allele might provide protection against CRC in worldwide populations, while MTRR 66G allele might increase the risk of CRC in Caucasians. Since potential confounders could not be ruled out completely, further studies were needed to confirm these results. PMID:22719222

  9. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism: epidemiology, metabolism and the associated diseases.

    PubMed

    Liew, Siaw-Cheok; Gupta, Esha Das

    2015-01-01

    The Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is associated with various diseases (vascular, cancers, neurology, diabetes, psoriasis, etc) with the epidemiology of the polymorphism of the C677T that varies dependent on the geography and ethnicity. The 5,10-Methylenetetrahydrofolate reductase (MTHFR) locus is mapped on chromosome 1 at the end of the short arm (1p36.6). This enzyme is important for the folate metabolism which is an integral process for cell metabolism in the DNA, RNA and protein methylation. The mutation of the MTHFR gene which causes the C677T polymorphism is located at exon 4 which results in the conversion of valine to alanine at codon 222, a common polymorphism that reduces the activity of this enzyme. The homozygous mutated subjects have higher homocysteine levels while the heterozygous mutated subjects have mildly raised homocysteine levels compared with the normal, non-mutated controls. Hyperhomocysteinemia is an emerging risk factor for various cardiovascular diseases and with the increasing significance of this polymorphism in view of the morbidity and mortality impact on the patients, further prevention strategies and nutritional recommendations with the supplementation of vitamin B12 and folic acid which reduces plasma homocysteine level would be necessary as part of future health education. This literature review therefore focuses on the recent evidence-based reports on the associations of the MTHFR C677T polymorphism and the various diseases globally. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism among Gaddi tribe of Indian state of Himachal Pradesh.

    PubMed

    Khan, Simi; Thakur, Sunil; Kallur, Saraswathy Nava; Ghosh, Pradeep Kumar; Sachdeva, Mohinder Pal; Vadlamudi, Raghavendra Rao

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism has been suggested to be positively associated with several disorders. Distribution of the mutant T-allele varies in ethnic and geographical populations of the world. The aim of the present study was to investigate the distribution of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in a transhumant (Gaddi) tribal population of Himachal Pradesh dwelling at high and middle altitude and exposed to strong ultraviolet radiation. A total of 486 samples (141 males and 345 females) were randomly enrolled from the individuals aged 25-75 years who were unrelated up to first cousin. Among Gaddis, genotype frequencies of CC, CT and TT were 67.90%, 27.78% and 4.32%, respectively. Among males and females distribution of genotype frequencies also followed a similar trend. The studied population was in Hardy-Weinberg equilibrium (χ(2 )= 2.213, df = 1, p = 0.136). Frequency of mutant T-allele in the Gaddi population was found to be 0.183, which might be due to European ancestry, endogamous nature and selection.

  11. The Importance of Homozygous Polymorphisms of Methylenetetrahydrofolate Reductase Gene in Romanian Patients with Idiopathic Venous Thromboembolism

    PubMed Central

    Hotoleanu, Cristina; Trifa, Adrian; Popp, Radu; Fodor, Daniela

    2013-01-01

    Background: Methylenetetrahydrofolate reductase (MTHFR) polymorphisms have recently raised the interest as a possible thrombophilic factors. Aims: We aimed to assess the frequency of the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms in idiopathic venous thromboembolism (VTE) in a Romanian population and the associated risk of VTE. Study Design: We performed a case-control transversal study including 90 patients diagnosed with VTE and 75 sex- and age-matched controls. Methods: MTHFR C677T and A1298C polymorphisms were detected using PCR-RFLP method. Results: The homozygous MTHFR 677TT genotype, present in 18.8% of patients with VTE versus 6.6% of controls, was significantly associated with VTE (p= 0.021, OR= 3.26, 95%CI (1.141–9.313)). The heterozygous MTHFR A1298C genotype, presenting the highest prevalence in the VTE group (34.4%) as well as in controls (37.3%), was not associated with VTE (p=0.7). No associations were found for heterozygous MTHFR C677T (with a frequency of 32.2% in VTE and 37.3% in controls, p=0.492), respective homozygous MTHFR A1298C genotype (with a frequency of 1.1% in VTE and 2.6% in controls, p=0.456). Conclusion: Among MTHFR polymorphisms, only homozygosity for MTHFR 677TT may be considered a risk factor for VTE; the MTHFR A1298C polymorphism is not significantly associated with an increased risk of VTE. PMID:25207100

  12. The impact of low molecular weight heparin on obstetric outcomes among unexplained recurrent miscarriages complicated with methylenetetrahydrofolate reductase gene polymorphism.

    PubMed

    Cetin, Orkun; Karaman, Erbil; Cim, Numan; Dirik, Deniz; Sahin, Hanim Guler; Kara, Erdal; Esen, Ramazan

    2017-01-01

    The association between methylenetetrahydrofolate reductase gene polymorphisms and unexplained recurrent miscarriage is elusive. The recommendations for improving pregnancy outcomes in these patients keep changing based on the available evidence. The aim of this study is to analyze the impact of low molecular weight heparin on obstetric outcomes of recurrent miscarriage patients complicated with methylenetetrahydrofolate reductase gene polymorphism. We reviewed medical records of 121 patients with a history of recurrent miscarriage complicated by methylenetetrahydrofolate reductase gene polymorphisms, retrospectively. From among them, 68 patients were treated only with folic acid and iron. The remaining 53 patients were treated with folic acid, iron and prophylactic doses of low molecular weight heparin. The subsequent pregnancy outcomes of these patients were noted. The live birth rate was higher in patients with anticoagulant therapy than in patients without anticoagulant therapy (48.5% vs. 69.8%, respectively, p: 0.015) and the congenital anomaly rate was lower in anticoagulant therapy group (17.6% vs. 3.8%, respectively, p: 0.022). The other obstetric outcomes were found to be similar between the two groups. The current study demonstrated that low molecular weight heparin improved the live birth rates among unex-plained recurrent miscarriage patients complicated with methylenetetrahydrofolate reductase gene polymorphisms. How-ever, the routine use of low molecular weight heparin did not improve the late pregnancy complications in these selected patients in the eastern region of our country. Further studies are needed to discriminate the effect of anticoagulation on the live birth rate of each of methylenetetrahydrofolate reductase gene polymorphism type.

  13. Role of methylenetetrahydrofolate reductase gene (MTHFR) 677C>T polymorphism in pediatric cerebrovascular disorders.

    PubMed

    Alsayouf, Hamza; Zamel, Khaled M; Heyer, Geoffrey L; Khuhro, A Latif; Kahwash, Samir B; de los Reyes, Emily C

    2011-03-01

    Homozygosity for the methylenetetrahydrofolate reductase (MTHFR) 677C>T mutation (MTHFR TT) has been linked to an increased risk for stroke, coronary artery disease, and migraine headaches. The authors analyzed the potential link between MTHFR 677C>T homozygosity and childhood stroke. A true association might facilitate screening, recurrence risk stratification, and treatment in patients with cerebrovascular disease. They performed a retrospective chart review of children tested for the MTHFR 677C>/T mutation; 533 patients underwent MTHFR testing, and 8% were homozygous for the MTHFR 677C>T mutation. There was no difference in the cohort compared with the prevalence in the general population. This suggests that the MTHFR 677 C>T polymorphism played a minimal role or no role in stroke risk. However, the data suggest that the MTHFR TT genotype may influence migraine susceptibility in children because there was a higher proportion of migraine patients (28.6%) with the MTHFR TT homozygous genotype.

  14. Methylenetetrahydrofolate reductase and transcobalamin genetic polymorphisms in human spontaneous abortion: biological and clinical implications

    PubMed Central

    Zetterberg, Henrik

    2004-01-01

    The pathogenesis of human spontaneous abortion involves a complex interaction of several genetic and environmental factors. The firm association between increased homocysteine concentration and neural tube defects (NTD) has led to the hypothesis that high concentrations of homocysteine might be embryotoxic and lead to decreased fetal viability. There are several genetic polymorphisms that are associated with defects in folate- and vitamin B12-dependent homocysteine metabolism. The methylenetetrahydrofolate reductase (MTHFR) 677C>T and 1298A>C polymorphisms cause elevated homocysteine concentration and are associated with an increased risk of NTD. Additionally, low concentration of vitamin B12 (cobalamin) or transcobalamin that delivers vitamin B12 to the cells of the body leads to hyperhomocysteinemia and is associated with NTD. This effect involves the transcobalamin (TC) 776C>G polymorphism. Importantly, the biochemical consequences of these polymorphisms can be modified by folate and vitamin B12 supplementation. In this review, I focus on recent studies on the role of hyperhomocysteinemia-associated polymorphisms in the pathogenesis of human spontaneous abortion and discuss the possibility that periconceptional supplementation with folate and vitamin B12 might lower the incidence of miscarriage in women planning a pregnancy. PMID:14969589

  15. 5,10-Methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTRR), and methionine synthase reductase (MTR) gene polymorphisms and adult meningioma risk.

    PubMed

    Zhang, Jun; Zhou, Yan-Wen; Shi, Hua-Ping; Wang, Yan-Zhong; Li, Gui-Ling; Yu, Hai-Tao; Xie, Xin-You

    2013-11-01

    The causes of meningiomas are not well understood. Folate metabolism gene polymorphisms have been shown to be associated with various human cancers. It is still controversial and ambiguous between the functional polymorphisms of folate metabolism genes 5,10-methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTRR), and methionine synthase reductase (MTR) and risk of adult meningioma. A population-based case–control study involving 600 meningioma patients (World Health Organization [WHO] Grade I, 391 cases; WHO Grade II, 167 cases; WHO Grade III, 42 cases) and 600 controls was done for the MTHFR C677T and A1298C, MTRR A66G, and MTR A2756G variants in Chinese Han population. The folate metabolism gene polymorphisms were determined by using a polymerase chain reaction–restriction fragment length polymorphism assay. Meningioma cases had a significantly lower frequency of MTHFR 677 TT genotype [odds ratio (OR) = 0.49, 95 % confidence interval (CI) 0.33–0.74; P = 0.001] and T allele (OR = 0.80, 95 % CI 0.67–0.95; P = 0.01) than controls. A significant association between risk of meningioma and MTRR 66 GG (OR = 1.41, 95 % CI 1.02–1.96; P = 0.04) was also observed. When stratifying by the WHO grade of meningioma, no association was found. Our study suggested that MTHFR C677T and MTRR A66G variants may affect the risk of adult meningioma in Chinese Han population.

  16. Methylenetetrahydrofolate reductase C677T and A1298C polymorphisms and gastric cancer susceptibility

    PubMed Central

    Xia, Lei-Zhou; Liu, Yi; Xu, Xiao-Zhou; Jiang, Peng-Cheng; Ma, Gui; Bu, Xue-Feng; Zhang, Yong-Jun; Yu, Feng; Xu, Ke-Sen; Li, Hua

    2014-01-01

    AIM: To identify the association between methylenetetrahydrofolate reductase (MTHFR) polymorphisms and gastric cancer (GC) susceptibility. METHODS: Systematic searches were performed on the electronic databases PubMed, ISI, Web of knowledge, CNKI and Wanfang, as well as manual searching of the references of the identified articles. A total of 26 papers were included in this meta-analysis. Overall and subgroup analyses were performed. Odds ratio (OR) and 95%CI were used to evaluate the associations between MTHFR polymorphisms and GC risk. The I2 statistics were used to evaluate between-study heterogeneity. Sensitivity analysis was also performed. RESULTS: Increased risk was found for the MTHFR C677T polymorphism under four genetic models (TT + CT vs CC: OR = 1.23, P = 0.002; T vs C: OR = 1.15, P = 0.001; TT vs CC: OR = 1.37, P = 0.0005; TT vs CT + CC: OR = 1.17, P = 0.0008). Subgroup analysis by ethnicity suggested that C677T polymorphism conferred a risk of GC in eastern but not in western populations. Stratification by tumor site showed an association between the C677T polymorphism and gastric cardia cancer and non-cardia GC in the worldwide population and in eastern populations. Regardless of comparisons with controls or diffuse-type GC, a positive association was found for the C677T polymorphism and an increased risk of intestinal-type GC in the whole population and in western populations. With regard to the A1298C polymorphism, we found that genotype CC was significantly decreased and conferred protection against GC in eastern populations (CC vs AA: OR = 0.44, P = 0.03; CC vs AC + AA: OR = 0.46, P = 0.04). CONCLUSION: MTHFR C677T polymorphism is a risk factor for GC, and the A1298C polymorphism may be a protective factor against GC in eastern populations. PMID:25170232

  17. Folate Pathway Gene Methylenetetrahydrofolate Reductase C677T Polymorphism and Alzheimer Disease Risk in Asian Population.

    PubMed

    Rai, Vandana

    2016-07-01

    The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and susceptibility to Alzheimers disease (AD) was controversial in previous studies. The present meta-analysis was designed to investigate the association of MTHFR C677T polymorphism with AD. Nine studies were identified by search of PubMed, Google Scholar, Elsevier, Springer Link databases, up to January 2013. Odds ratios (ORs) with corresponding 95 % confidence interval (CI) were calculated using fixed effects model or random effects model. All statistical analysis was done by Mix version 1.7. MTHFR C677T polymorphism had a significant association with susceptibility to AD in all genetic models (for T vs C: OR 1.29, 95 % CI 1.15-1.44, p < 0.0001; for TT + CT vs CC: OR 1.38, 95 % CI 1.16-1.364, p = 0.0002; for TT vs CC: OR 1.60, 95 % CI 1.25-2.04, p = 0.0001; for CT vs CC: OR 1.28, 95 % CI 1.1-1.53, p < 0.008; for TT vs CT + CC: OR 1.37, 95 % CI 1.12-1.67, p = 0.002). Results from present meta-analysis supported that the MTHFR C677T polymorphism was associated with an increased risk of AD in Asian population.

  18. Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and susceptibility to ischemic stroke: a meta-analysis.

    PubMed

    Li, Pingping; Qin, Chao

    2014-02-10

    Associations between 5,10-methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism and ischemic stroke have been reported (Ariyaratnam et al., 2007; Banerjee et al., 2007; Casas et al., 2004), but the results of these studies are inconsistent. To investigate the possible associations between the MTHFR gene polymorphism and ischemic stroke, we performed a meta-analysis. Nineteen case-control studies associated with MTHFR gene C667T involving 2223 cases and 2936 controls were included. Heterogeneity among studies was evaluated with I(2) and Egger's test and an inverted funnel plot was used to assess publication bias. Odds ratio (OR) was observed to identify the associations. Statistically significant association with ischemic stroke was identified for allele T polymorphism of MTHFR [fixed-effects OR=1.28, 95% confidence interval (95% CI): 1.17-1.40, P<0.00001] and marginally significant association was detected with genotype CT of MTHFR (fixed-effects OR=1.13, 95% CI: 1.01-127, P=0.04) and genotype TT of MTHFR (fixed-effects OR=1.43, 95% CI: 1.20-1.70, P<0.001). The results suggested that the MTHFR C667T genetic polymorphism was significantly associated with increased risk of ischemic stroke. © 2013.

  19. Individualized supplementation of folic acid according to polymorphisms of methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR) reduced pregnant complications.

    PubMed

    Li, Xiujuan; Jiang, Jing; Xu, Min; Xu, Mei; Yang, Yan; Lu, Wei; Yu, Xuemei; Ma, Jianlin; Pan, Jiakui

    2015-01-01

    This study aimed to detect the genotype distributions and allele frequencies of methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G polymorphisms of pregnant women in Jiaodong region in China, and to investigate whether folic acid supplementation affect the pregnancy complications. A total of 7,812 pregnant women from the Jiaodong region in Shandong province in China. By using Taqman-MGB, 2,928 pregnant women (case group) were tested for the genotype distributions and allele frequencies of MTHFR C677T, A1298C and MTRR A66G polymorphisms. Folic acid metabolism ability was ranked at four levels and then pregnant women in different rank group were supplemented with different doses of folic acid. Their pregnancy complications were followed up and compared with 4,884 pregnant women without folic acid supplementation (control group) in the same hospital. The allele frequencies of MTHFR C677T were 49.1 and 50.9%; those of MTHFR A1298C were 80.2 and 19.8%, and those of MTRR A66G were 74.1 and 25.9%. After supplemented with folic acid, the complication rates in different age groups were significantly reduced, especially for gestational diabetes mellitus and hypertension. Periconceptional folic acid supplementation and healthcare following gene polymorphism testing may be a powerful measure to decrease congenital malformations. © 2015 S. Karger AG, Basel.

  20. Polymorphisms of methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), and thymidylate synthase (TYMS) in multiple myeloma risk.

    PubMed

    Lima, Carmen S P; Ortega, Manoela M; Ozelo, Margareth C; Araujo, Renato C; De Souza, Cármino A; Lorand-Metze, Irene; Annichino-Bizzacchi, Joyce M; Costa, Fernando F

    2008-03-01

    We tested whether the polymorphisms of the methylenetetrahydrofolate reductase gene, MTHFR C677T and A1298C, the methionine synthase gene, MTR A2756G, the methionine synthase reductase gene, MTRR A66G, and the thymidylate synthase gene, TYMS 2R-->3R, involved in folate and methionine metabolism, altered the risk for multiple myeloma (MM). Genomic DNA from 123MM patients and 188 controls was analysed by polymerase chain reaction and restriction digestion for the polymorphism analyses. The frequency of the MTR 2756 AG plus GG genotype was higher in patients than in controls (39.8% versus 23.4%, P=0.001). Individual carriers of the variant allele G had a 2.31 (95% CI: 1.38-3.87)-fold increased risk for MM compared with others. In contrast, similar frequencies of the MTHFR, the MTRR and the TYMS genotypes were seen in patients and controls. These results suggest, for the first time, a role for the MTR A2756G polymorphism in MM risk in our country, but should be confirmed by large-scale epidemiological studies with patients and controls age matched.

  1. Meta-analysis of methylenetetrahydrofolate reductase (MTHFR) polymorphisms affecting methotrexate toxicity

    PubMed Central

    Fisher, Mark C.; Cronstein, Bruce N.

    2008-01-01

    Objective Methotrexate is an effective therapy for Rheumatoid Arthritis (RA) but is also associated with toxicity. Pharmacogenetics is the systematic evaluation of the role of genetic differences in the efficacy and toxicity of therapeutic interventions. Because the results of small pharmacogenetic studies are often misleading, we undertook a meta-analysis of published studies to determine the role of polymorphisms in the therapeutic efficacy and toxicity of methotrexate. Methods A search of PUBMED produced 55 publications which were then reviewed for relevance to methotrexate toxicity and efficacy in patients with RA. To ensure that no studies were missed, each polymorphism found was then entered as an independent search string and all results were again reviewed. Results Only 2 polymorphisms (C677T and A1298C in methylenetetrahydrofolate reductase, MTHFR, total: 8 studies) relevant to methotrexate metabolism and efficacy had sufficient data to perform a meta-analysis of their association with toxicity; there was no polymorphism with sufficient data to perform a meta-analysis of efficacy. In a fixed effects model, the C677T polymorphism was associated with increased toxicity (OR 1.71, CI 1.32 – 2.21, p<0.001). The A1298C polymorphism was not associated with increased toxicity (OR 1.12, CI 0.79 – 1.6, p=0.626). Conclusions As pharmacogenetics evolves, more data are needed to assess the role of various polymorphisms for drug efficacy and toxicity. These results illustrate the paucity of reliable pharmacogenetic data on a commonly used anti-rheumatic drug and the potential role of pharmacogenetics in tailoring drug therapy for an individual patient. PMID:19208607

  2. The effect of methylenetetrahydrofolate reductase polymorphisms on susceptibility to human papilloma virus infection and cervical cancer.

    PubMed

    Hajiesmaeil, Mogge; Tafvizi, Farzaneh; Sarmadi, Soheila

    2016-12-01

    Cervical cancer is the third most common cancer among women worldwide. Several factors lead to cervical cancer, among which human papilloma virus (HPV) infection has a prominent role. Methylenetetrahydrofolate reductase (MTHFR) is crucial in folate metabolic pathway and plays an important role in DNA synthesis and DNA methylation. MTHFR gene polymorphisms, including C677T and A1298C, lead to reduced enzyme activity. This case-control study aims to illustrate the association between MTHFR gene polymorphisms and the risk of cervical cancer. This study was conducted on 196 samples, which included 96 cervical biopsy samples compared to 100 Pap smear samples of normal healthy women without HPV infection. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used for the MTHFR polymorphism detection, followed by fluorescent amplification-based specific hybridization PCR method to detect HPV16 and HPV18. The results show that the MTHFR 677TT genotype plays a protective role in cervical cancer (P=0.0030) (OR=0.21, 95% confidence interval [CI]: 0.07-0.59). Furthermore, there was a strong significant association between MTHFR 1298CC genotype and the risk of cervical cancer (OR=10.69; 95% CI: 4.28-26.71, P=0.0001). It can be concluded that A1298C polymorphism is a genetic risk factor for cervical cancer in the assessed Iranian population group. It seems that MTHFR 1298CC genotype is more susceptible to HPV 16 infection. Combination analysis of MTHFR C677T and A1298C polymorphisms revealed that combined MTHFR 677CC and 1298CC are strongly associated with a risk of cervical cancer.

  3. Methylenetetrahydrofolate reductase (MTHFR) polymorphism susceptibility to schizophrenia and bipolar disorder: an updated meta-analysis.

    PubMed

    Hu, Cai-Yun; Qian, Zhen-Zhong; Gong, Feng-Feng; Lu, Shan-Shan; Feng, Fang; Wu, Yi-Le; Yang, Hui-Yun; Sun, Ye-Huan

    2015-02-01

    Previous studies examining the possible role of the methylenetetrahydrofolate reductase (MTHFR) polymorphisms in the development of schizophrenia (SZ) and bipolar disorder (BPD) have provided inconclusive findings, this meta-analysis was therefore designed to get a more reliable assessment. A total of 38 articles were identified through a search of electronic databases, up to 27 February 2014. Odds ratios (ORs) with 95% confidence interval (CIs) were calculated using random effects models. Meta-analysis showed that MTHFR C677T was significantly associated with SZ, the highest OR was found for the recessive model (for TT vs. CT + CC: OR = 1.34, 95% CI: 1.18-1.53); a marginal association of MTHFR C677T with increased risk of BPD has also been found for the recessive model (OR = 1.26, 95% CI: 1.00-1.59). Subgroup analysis by ethnicity indicated that the significant association with SZ and BPD existed among Asian and African populations, but not for the white. MTHFR A1298C was significant associated with SZ, the highest OR for the dominant model (OR = 1.13, 95% CI: 1.03-1.24). Subgroup analysis indicated a significant association with SZ existed in Asian populations, not among the white populations and no significant association was detected between the MTHFR A1298C and BPD in all groups. We conclude that MTHFR polymorphism is associated with SZ and BPD among Asian, African populations, but not the white.

  4. Is methylenetetrahydrofolate reductase (MTHFR) gene A1298C polymorphism related with varicocele risk?

    PubMed

    Ucar, V B; Nami, B; Acar, H; Kilinç, M

    2015-02-01

    Varicocele is one of the main reasons for male infertility the exact aetiology of which remains unclear. Methylenetetrahydrofolate reductase (MTHFR) is important for DNA synthesis and methylation, which has a key role during spermatogenesis. Numerous literature suggests that the MTHFR polymorphism may be genetic risk factors for male infertility. In this study, we evaluated C677T and A1298C MTHFR gene polymorphism frequency in patients with varicocele and normal men. A total of 107 varicocele patients and 109 fertile healthy individuals were included. Genotyping of the MTHFR gene in C677T and A1298C base pairs carried out by using real-time PCR technique and afterwards, the statistical analysis accomplished. There is a statistical difference for the frequency of 1298AA genotype in patients with varicocele compared with normal controls (P = 0.0051, OR = 2.2750). Instead, subsequently, 1298/A allel frequency in patient group was significantly higher in comparison with control group (P = 0.0174). According to our results, 1298AA genotype in MTHFR gene raises the risk of varicocele approximately 2.3 times more compared with men carrying other genotypes. The results show that genetic factors have an important role in the molecular basis of varicocele. © 2014 Blackwell Verlag GmbH.

  5. Methylenetetrahydrofolate Reductase C677T Polymorphism and Risk for Male Infertility in Asian Population.

    PubMed

    Rai, Vandana; Kumar, Pradeep

    2017-07-01

    Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme of folate pathway and required for DNA synthesis and methylation. MTHFE C677T polymorphisms is reported as risk factors for various diseases and disorders like birth defects, metabolic, neurological, psychiatric disorders, and cancers. Several studies have investigated association between the MTHFR C677T polymorphism and male infertility. To assess the risk associated with MTHFR C677T polymorphism in Asian population, a meta-analysis was performed. Included articles were collected from the following electronic databases: PubMed, Google Scholar, and Science direct up to March 2015. Risk was estimated as pooled odds ratios (ORs) with confidence intervals (CIs) for assessment. Seventeen case-control studies involving 4392 breast infertile males and 3667 fertile males were found suitable for the inclusion in the present meta-analysis. Results showed that the C677T polymorphism was significantly associated with male infertility in Asian population using all the five genetic models (ORT vs. C (allele contrast model) = 1.86, 95% CI 1.7-2.0; ORTT vs. CC (homozygote model) = 1.96, 95% CI 1.67-2.30; ORCT vs. CC (co-dominant model) = 1.40, 95% CI 1.18-1.62; ORTT+CT vs. CC (dominant model) = 1.53, 95% CI 1.30-1.77; ORTT vs. CT+CC (recessive model) = 1.67, 95% CI 1.44-1.92). In conclusion, results of present meta-analysis strongly supported an association between C677T polymorphism and male infertility in Asians.

  6. Association between methylenetetrahydrofolate reductase C677T polymorphism and psoriasis: A meta-analysis.

    PubMed

    Wu, Dongze; Shi, Deshun; Yang, Li; Zhu, Xiaoliang

    2016-02-01

    Several studies have evaluated the associations between methylenetetrahydrofolate reductase (MTHFR) C677T and psoriasis. However, the results remain inconclusive. The objective of the present study was to conduct a qualitative and quantitative meta-analysis investigating the associations between MTHFR C677T and psoriasis. A published work search of PubMed, Embase, Web of Science and Chinese National Knowledge Infrastructure database were conducted to identify all publications concerning MTHFR C677T polymorphism and psoriasis on 1 October 2014. The principal outcome measure for evaluating the strength of the association was crude odds ratios along with their corresponding 95% confidence intervals. Data were extracted and statistical analyses were implemented using STATA version 12.0 software. A total of 1179 psoriatic cases and 937 controls from five case-control studies concentrating on the association between MTHFR C677T polymorphism and psoriasis were included in this qualitative meta-analysis. Pooled analysis revealed that there is no association between this polymorphism and susceptibility to psoriasis in dominant, recessive, allele and additive models under a random-effect model. However, a marginal significant association was found in the overdominant model under fixed-effect model. Subgroup analysis of ethnicity demonstrated that there is no association between MTHFR C677T polymorphism and either Asian or European psoriatic patients. In conclusion, MTHFR C677T polymorphism, qualitatively, is not a genetic factor for the pathogenesis of psoriasis but could quantitatively reflect the severity of psoriasis to some extent. © 2015 Japanese Dermatological Association.

  7. Riboflavin status modifies the effects of methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) polymorphisms on homocysteine.

    PubMed

    García-Minguillán, Carlos J; Fernandez-Ballart, Joan D; Ceruelo, Santiago; Ríos, Lídia; Bueno, Olalla; Berrocal-Zaragoza, Maria Isabel; Molloy, Anne M; Ueland, Per M; Meyer, Klaus; Murphy, Michelle M

    2014-11-01

    Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR), riboflavin-dependent enzymes, participate in homocysteine metabolism. Reported effects of riboflavin status on the association between the MTHFR 677C>T polymorphism and homocysteine vary, and the effects of the MTRR 66A>G or MTRR 524C>T polymorphisms on homocysteine are unclear. We tested the hypothesis that the effects of the MTHFR 677C>T, MTRR 66A>G and MTRR 524C>T polymorphisms on fasting plasma total homocysteine (tHcy) depend on riboflavin status (erythrocyte glutathionine reductase activation coefficient, optimum: <1.2; marginally deficient: 1.2-1.4; deficient: ≥1.4) in 771 adults aged 18-75 years. MTHFR 677T allele carriers with middle or low tertile plasma folate (<14.7 nmol/L) had 8.2 % higher tHcy compared to the 677CC genotype (p < 0.01). This effect was eliminated when riboflavin status was optimal (p for interaction: 0.048). In the lowest cobalamin quartile (≤273 pmol/L), riboflavin status modifies the relationship between the MTRR 66 A>G polymorphism and tHcy (p for interaction: 0.034). tHcy was 6.6 % higher in MTRR 66G allele carriers compared to the 66AA genotype with marginally deficient or optimal riboflavin status, but there was no difference when riboflavin status was deficient (p for interaction: 0.059). tHcy was 13.7 % higher in MTRR 524T allele carriers compared to the 524CC genotype when cobalamin status was low (p < 0.01), but no difference was observed when we stratified by riboflavin status. The effect of the MTHFR 677C>T polymorphism on tHcy depends on riboflavin status, that of the MTRR 66A>G polymorphism on cobalamin and riboflavin status and that of the MTRR 524C>T polymorphism on cobalamin status.

  8. Effects of methionine synthase and methylenetetrahydrofolate reductase gene polymorphisms on markers of one-carbon metabolism.

    PubMed

    Ho, Vikki; Massey, Thomas E; King, Will D

    2013-11-01

    Genetic and nutritional factors play a role in determining the functionality of the one-carbon (1C) metabolism cycle, a network of biochemical reactions critical to intracellular processes. Genes encoding enzymes for methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MTR) may determine biomarkers of the cycle including homocysteine (HCY), S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH). MTHFR C677T is an established genetic determinant of HCY but less is known of its effect on SAM and SAH. Conversely, the relationship between MTR A2756G and HCY remains inconclusive, and its effect on SAM and SAH has only been previously investigated in a female-specific population. Folate and vitamin B12 are essential substrate and cofactor of 1C metabolism; thus, consideration of gene-nutrient interactions may clarify the role of genetic determinants of HCY, SAM and SAH. This cross-sectional study included 570 healthy volunteers from Kingston, Ontario, Ottawa, Ontario and Halifax, Nova Scotia, Canada. Least squares regression was used to examine the effects of MTR and MTHFR polymorphisms on plasma HCY, SAM and SAH concentrations; gene-gene and gene-nutrient interactions were considered with the inclusion of cross-products in the model. Main effects of MTR and MTHFR polymorphisms on HCY concentrations were observed; however, no gene-gene or gene-nutrient interactions were found. No association was observed for SAM. For SAH, interactions between MTR and MTHFR polymorphisms, and MTHFR polymorphism and serum folate were found. The findings of this research provide evidence that HCY and SAH, biomarkers of 1C metabolism, are influenced by genetic and nutritional factors and their interactions.

  9. Methylenetetrahydrofolate Reductase (MTHFR) C677T Polymorphism and Alzheimer Disease Risk: a Meta-Analysis.

    PubMed

    Rai, Vandana

    2017-03-01

    Methylenetetrahydrofolate reductase (MTHFR) is key enzyme of folate/homocysteine pathway. Case control association studies on MTHFR C677T polymorphism and Alzheimer's disease (AD) have been repeatedly performed over the last two decades, but the results are inconclusive. The aim of the present study was to assess the risk of MTHFR C677T polymorphism for AD. Forty-one studies were identified by a search of PubMed, Google Scholar, Elsevier, and Springer Link databases, up to January 2015. Odds ratios (ORs) with corresponding 95 % confidence interval (CI) were calculated using fixed effect model or random effect model. The subgroup analyses based on ethnicity were performed. MTHFR C677T polymorphism had a significant association with susceptibility to AD in all genetic models (for T vs C OR = 1.29, 95 % CI = 1.07-1.56, p = 0.003; for TT + CT vs CC OR = 1.29, 95 % CI = 1.19-1.40, p = 0.0004; for TT vs CC OR = 1.31, 95 % CI = 1.16-1.48, p = 0.001; for CT vs CC OR = 1.24, 95 % CI = 1.13-1.35, p < 0.004; and for TT vs CT + CC OR = 1.13, 95 % CI = 1.00-1.28, p = 0.02). Results of present meta-analysis supported that the MTHFR C677T polymorphism was associated with an increased risk of AD.

  10. Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and FOLFOX response in colorectal cancer patients

    PubMed Central

    Etienne-Grimaldi, Marie-Christine; Milano, Gérard; Maindrault-Gœbel, Frédérique; Chibaudel, Benoist; Formento, Jean-Louis; Francoual, Mireille; Lledo, Gérard; André, Thierry; Mabro, May; Mineur, Laurent; Flesch, Michel; Carola, Elisabeth; de Gramont, Aimery

    2010-01-01

    AIMS To test prospectively the predictive value of germinal gene polymorphisms related to fluorouracil (FU) and oxaliplatin (Oxa) pharmacodynamics on toxicity and responsiveness of colorectal cancer (CRC) patients receiving FOLFOX therapy. METHODS Advanced CRC patients (n= 117) receiving FOLFOX 7 therapy were enrolled. Gene polymorphisms relevant for FU [thymidylate synthase (TYMS, 28 bp repeats including the G→C mutation + 6 bp deletion in 3'UTR), methylenetetrahydrofolate reductase (MTHFR, 677C→T, 1298A→C), dihydropyrimidine deshydrogenase (IVS14+1G→A) and Oxa: glutathione S-transferase (GST) π (105Ile→Val, 114Ala→Val), excision repair cross-complementing group 1 (ERCC1) (118AAT→AAC), ERCC2 (XPD, 751Lys→Gln) and XRCC1 (399Arg→Gln)] were determined (blood mononuclear cells). RESULTS None of the genotypes was predictive of toxicity. Response rate (54.7% complete response + partial response) was related to FU pharmacogenetics, with both 677C→T (P= 0.042) and 1298A→C (P= 0.004) MTHFR genotypes linked to clinical response. Importantly, the score of favourable MTHFR alleles (677T and 1298C) was positively linked to response, with response rates of 37.1, 53.3, 62.5 and 80.0% in patients bearing no, one, two or three favourable alleles, respectively (P= 0.040). Polymorphisms of genes related to Oxa pharmacodynamics showed an influence on progression-free survival, with a better outcome in patients bearing GSTπ 105 Val/Val genotype or XPD 751Lys-containing genotype (P= 0.054). CONCLUSIONS These results show that response to FOLFOX therapy in CRC patients may be driven by MTHFR germinal polymorphisms. PMID:20078613

  11. Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and promoter methylation in cervical oncogenic lesions and cancer

    PubMed Central

    Botezatu, Anca; Socolov, Demetra; Iancu, Iulia V; Huica, Irina; Plesa, Adriana; Ungureanu, Carmen; Anton, Gabriela

    2013-01-01

    The aim of this study was to investigate the role of methylenetetrahydrofolate reductase (MTHFR) polymorphisms and MTHFR methylation pattern in cervical lesions development among women from Romania, a country with high prevalence of human papillomavirus (HPV) cervical infections. To achieve this goal, blood samples and cervical cytology specimens (n = 77)/tumour tissue specimens (n = 23) were investigated. As control, blood and negative cytological smears (n = 50) were used. A statistically significant association was found between T allele of C677T polymorphism and cervical lesions, heterozygote women presenting a threefold increased risk (normal/cervical lesions and tumours: wild homozygote 34/41 (0.68/0.41), heterozygote 14/51 (0.28/0.51), mutant homozygote 2/8 (0.04/0.08); OR = 3.081, P = 0.0035). Using χ square test for the control group, the HPV-negative and HPV-positive patients with cervix lesions, a significant correlation between viral infection and T allele of C677T polymorphism (P = 0.0287) was found. The MTHFR promoter was methylated in all HGSIL and tumour samples, significant differences being noted between HPV-positive samples, control group and cases of cervical dysplastic lesions without HPV DNA (P < 0. 0001) and between samples from patients with high-risk (hr)HPV versus low-risk (lr)HPV (P = 0.0026). No correlations between polymorphisms and methylation were observed. In Romania, individuals carrying T allele are susceptible for cervical lesions. MTHFR promoter methylation is associated with cervical severity lesions and with hrHPV. PMID:23444906

  12. Methylenetetrahydrofolate Reductase Gene Polymorphism and Risk of Type 2 Diabetes Mellitus

    PubMed Central

    Yang, Na-Na; Li, Le-Qun

    2013-01-01

    Objective This review aimed to comprehensively assess the literature examining a possible link between the rs1801133 polymorphism (677C→T) in the gene encoding the methylenetetrahydrofolate reductase (MTHFR) gene and risk of type 2 diabetes mellitus (DM). Research Design and Methods Several research databases were systematically searched for studies examining the genotype at the rs1801133 polymorphism in healthy control individuals and individuals with type 2 DM. Genotype frequency data were examined across all studies and across subsets of studies according to ethnicity and presence of serious DM-related complications. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Results A total of 4855 individuals with type 2 DM and 5242 healthy controls from 15 countries comprising Asian, Caucasian and African ethnicities were found to satisfy the inclusion criteria and included in the review. Genotype at the rs1801133 polymorphism was not consistently associated with either increased or reduced risk of type 2 DM; the OR across all studies was 0.91 (95%CI 0.82 to 1.00) for the C- vs. T-allele, 0.88 (0.75 to 1.03) for CC vs. CT+TT, 0.82 (0.71 to 0.95) for CC vs. TT, and 1.15 (1.03 to 1.29) for TT vs. CC+CT. Similar results were found when the meta-analysis was repeated separately for each ethnic subgroup, and for subgroups with or without serious DM-related complications. Conclusions There does not appear to be compelling evidence of an association between the genotype at the rs1801133 polymorphism of the MTHFR gene and risk of type 2 DM. PMID:24023947

  13. Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and promoter methylation in cervical oncogenic lesions and cancer.

    PubMed

    Botezatu, Anca; Socolov, Demetra; Iancu, Iulia V; Huica, Irina; Plesa, Adriana; Ungureanu, Carmen; Anton, Gabriela

    2013-04-01

    The aim of this study was to investigate the role of methylenetetrahydrofolate reductase (MTHFR) polymorphisms and MTHFR methylation pattern in cervical lesions development among women from Romania, a country with high prevalence of human papillomavirus (HPV) cervical infections. To achieve this goal, blood samples and cervical cytology specimens (n = 77)/tumour tissue specimens (n = 23) were investigated. As control, blood and negative cytological smears (n = 50) were used. A statistically significant association was found between T allele of C677T polymorphism and cervical lesions, heterozygote women presenting a threefold increased risk (normal/cervical lesions and tumours: wild homozygote 34/41 (0.68/0.41), heterozygote 14/51 (0.28/0.51), mutant homozygote 2/8 (0.04/0.08); OR = 3.081, P = 0.0035). Using χ square test for the control group, the HPV-negative and HPV-positive patients with cervix lesions, a significant correlation between viral infection and T allele of C677T polymorphism (P = 0.0287) was found. The MTHFR promoter was methylated in all HGSIL and tumour samples, significant differences being noted between HPV-positive samples, control group and cases of cervical dysplastic lesions without HPV DNA (P < 0. 0001) and between samples from patients with high-risk (hr)HPV versus low-risk (lr)HPV (P = 0.0026). No correlations between polymorphisms and methylation were observed. In Romania, individuals carrying T allele are susceptible for cervical lesions. MTHFR promoter methylation is associated with cervical severity lesions and with hrHPV. © 2013 The Authors. Published by Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

  14. Homocysteine and Stroke Risk: Modifying Effect of Methylenetetrahydrofolate Reductase C677T Polymorphism and Folic Acid Intervention.

    PubMed

    Zhao, Min; Wang, Xiaobin; He, Mingli; Qin, Xianhui; Tang, Genfu; Huo, Yong; Li, Jianping; Fu, Jia; Huang, Xiao; Cheng, Xiaoshu; Wang, Binyan; Hou, Fan Fan; Sun, Ningling; Cai, Yefeng

    2017-05-01

    Elevated blood homocysteine concentration increases the risk of stroke, especially among hypertensive individuals. Homocysteine is largely affected by the methylenetetrahydrofolate reductase C677T polymorphism and folate status. Among hypertensive patients, we aimed to test the hypothesis that the association between homocysteine and stroke can be modified by the methylenetetrahydrofolate reductase C677T polymorphism and folic acid intervention. We analyzed the data of 20 424 hypertensive adults enrolled in the China Stroke Primary Prevention Trial. The participants, first stratified by methylenetetrahydrofolate reductase genotype, were randomly assigned to receive double-blind treatments of 10-mg enalapril and 0.8-mg folic acid or 10-mg enalapril only. The participants were followed up for a median of 4.5 years. In the control group, baseline log-transformed homocysteine was associated with an increased risk of first stroke among participants with the CC/CT genotype (hazard ratio, 3.1; 1.1-9.2), but not among participants with the TT genotype (hazard ratio, 0.7; 0.2-2.1), indicating a significant gene-homocysteine interaction (P=0.008). In the folic acid intervention group, homocysteine showed no significant effect on stroke regardless of genotype. Consistently, folic acid intervention significantly reduced stroke risk in participants with CC/CT genotypes and high homocysteine levels (tertile 3; hazard ratio, 0.73; 0.55-0.97). In Chinese hypertensive patients, the effect of homocysteine on the first stroke was significantly modified by the methylenetetrahydrofolate reductase C677T genotype and folic acid supplementation. Such information may help to more precisely predict stroke risk and develop folic acid interventions tailored to individual genetic background and nutritional status. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00794885. © 2017 American Heart Association, Inc.

  15. Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) gene polymorphisms as risk factors for hepatocellular carcinoma in a Korean population.

    PubMed

    Kwak, Sun Young; Kim, Un Kyung; Cho, Hyo Jin; Lee, Hee Keun; Kim, Hye Jin; Kim, Nam Keun; Hwang, Seong Gyu

    2008-01-01

    Hepatocellular carcinoma (HCC) is the third most frequent cause of cancer death in South Korea, but genetic susceptibility factors of HCC have not been examined extensively. Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) play an essential role in both DNA synthesis and methylation and polymorphisms in the MTHFR gene, 677C>T, 1298A>C and the MTRR gene, 66A>G, are associated with several types of malignancy. In this study, the allelic frequencies and genotype distribution of three polymorphisms in the MTHFR and MTRR genes from 96 hepatocellular carcinoma (HCC) patients and 201 controls were examined to assess the association between these polymorphisms and the development of HCC in this Korean population. The 66AG+GG (G allele-bearing) genotype of the MTRR gene was significantly associated with an increased risk of HCC (odds ratio, OR, 1.687; 95% confidence interval, CI=1.022-2.787). Moreover, the combination of MTHFR 1298AA/MTRR 66AG+GG (OR=1.854, 95% CI=1.005-3.420) and MTHFR 1298AC+CC/MTRR 66AG+GG (OR=2.733, 95% CI=1.195-6.249) showed a significant association with HCC risk. In the data classified by age and etiology, MTRR 66A>G over the age of 65 years, MTHFR 1298A>C under the age of 65 years and the MTRR 66AG+GG genotype in the hepatitis B virus (HBV) patients were increased risk factors for the disease. The MTHFR 1298A>C and the MTRR 66A>G genotypes were associated with an increased risk of HCC in this Korean population. Further studies involving larger and varied populations could provide a potential tool for cancer risk assessment in patients who are at risk of developing HCC.

  16. 5,10 Methylenetetrahydrofolate reductase genetic polymorphism as a risk factor for neural tube defects

    SciTech Connect

    Ou, C.Y.; Brown, V.K.; Khoury, M.J.

    1996-06-28

    Persons with a thermolabile form of the enzyme 5,10 methylenetetrahydrofolate reductase (MTHFR) have reduced enzyme activity and increased plasma homocysteine which can be lowered by supplemental folic acid. Thermolability of the enzyme has recently been shown to be caused by a common mutation (677C{sup {r_arrow}}T) in the MTHFR gene. We studied 41 fibroblast cultures from NTD-affected fetuses and compared their genotypes with those of 109 blood specimens from individuals in the general population. 677C{sup {r_arrow}}T homozygosity was associated with a 7.2 fold increased risk for NTDs (95% confidence interval: 1.8-30.3; p value: 0.001). These preliminary data suggest that the 677C{sup {r_arrow}}T polymorphism of the MTHFR gene is a risk factor for spina bifida and anencephaly that may provide a partial biologic explanation for why folic acid prevents these types of NTD. 13 refs., 1 fig., 1 tab.

  17. Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and susceptibility for cervical lesions: a meta-analysis.

    PubMed

    Long, Shuyu; Yang, Xingliang; Liu, Xiaojiao; Yang, Pei

    2012-01-01

    The association between the methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and the susceptibility to cervical lesions was unclear. This study was designed to investigate their precise association using a large-scale meta-analysis. The previous 16 studies were identified by searching PubMed, Embase and CBM databases. The crude odds ratios and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the MTHFR C677T/A1298C polymorphisms and the susceptibility to the cervical lesions. The subgroup analyses were made on the following: pathological history, geographic region, ethnicity, source of controls and source of DNA for genotyping. Neither of the polymorphisms had a significant association with the susceptibility to the cervical lesions in all genetic models. Similar results were found in the subgroup analyses. No association was found between the MTHFR C677T polymorphism and the cervical lesions in the Asia or the America populations though a significant inverse association was found in the Europe population (additive model: P = 0.006, OR = 0.83, 95% CI = 0.72-0.95; CT vs. CC: P = 0.05, OR = 0.83, 95% CI = 0.69-1.00; TT vs. CC: P = 0.05, OR = 0.73, 95% CI = 0.53-1.00). Interestingly, women with the MTHFR A1298C polymorphisms had a marginally increased susceptibility to invasive cancer (ICC) when compared with no carriers but no statistically significant difference in the dominant model (P = 0.06, OR = 1.21, 95% CI = 0.99-1.49) and AC vs. AA (P = 0.09, OR = 1.21, 95% CI = 0.97-1.51). The MTHFR C677T and A1298C polymorphisms may not increase the susceptibility to cervical lesions. However, the meta-analysis reveals a negative association between the MTHFR C677T polymorphisms and the cervical lesions, especially in the European populations. The marginal association between the MTHFR A1298C polymorphisms and the susceptibility to cervical cancer requires a further study.

  18. Methylenetetrahydrofolate Reductase (MTHFR) Polymorphisms and Susceptibility for Cervical Lesions: A Meta-Analysis

    PubMed Central

    Liu, Xiaojiao; Yang, Pei

    2012-01-01

    Background The association between the methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and the susceptibility to cervical lesions was unclear. This study was designed to investigate their precise association using a large-scale meta-analysis. Methods The previous 16 studies were identified by searching PubMed, Embase and CBM databases. The crude odds ratios and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the MTHFR C677T/A1298C polymorphisms and the susceptibility to the cervical lesions. The subgroup analyses were made on the following: pathological history, geographic region, ethnicity, source of controls and source of DNA for genotyping. Results Neither of the polymorphisms had a significant association with the susceptibility to the cervical lesions in all genetic models. Similar results were found in the subgroup analyses. No association was found between the MTHFR C677T polymorphism and the cervical lesions in the Asia or the America populations though a significant inverse association was found in the Europe population (additive model: P = 0.006, OR = 0.83, 95% CI = 0.72–0.95; CT vs. CC: P = 0.05, OR = 0.83, 95% CI = 0.69–1.00; TT vs. CC: P = 0.05, OR = 0.73, 95% CI = 0.53–1.00). Interestingly, women with the MTHFR A1298C polymorphisms had a marginally increased susceptibility to invasive cancer (ICC) when compared with no carriers but no statistically significant difference in the dominant model (P = 0.06, OR = 1.21, 95% CI = 0.99–1.49) and AC vs. AA (P = 0.09, OR = 1.21, 95% CI = 0.97–1.51). Conclusions The MTHFR C677T and A1298C polymorphisms may not increase the susceptibility to cervical lesions. However, the meta-analysis reveals a negative association between the MTHFR C677T polymorphisms and the cervical lesions, especially in the European populations. The marginal association between the MTHFR A1298C

  19. Methylenetetrahydrofolate reductase C677T genetic polymorphisms and risk of leukaemia among the North Indian population.

    PubMed

    Hussain, Syed Rizwan; Naqvi, Hena; Raza, Syed Tasleem; Ahmed, Faisal; Babu, Sunil G; Kumar, Ashutosh; Zaidi, Zeashan Haider; Mahdi, Farzana

    2012-08-01

    Leukaemia is a heterogeneous disease in which haematopoietic progenitor cells acquire genetic lesions that lead to a block in differentiation, increased self-renewal, and unregulated proliferation. The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR), involved in folate metabolism, plays a crucial role in cells because folate availability is important for DNA integrity. The aim of this case-control study was to evaluate the association of the C677T MTHFR gene polymorphism with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL), chronic myeloid leukaemia (CML) and chronic lymphocytic leukaemia (CLL). A total of 275 leukaemia cases - including AML (n = 112), ALL (n = 81), CML (n = 43), CLL (n = 39) - and 251 age/sex-matched healthy control individuals participated in this study. MTHFR C677T polymorphisms in the cases and controls were evaluated by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The average MTHFR 677CC, 677CT, 677TT genotype frequencies of total leukaemia cases were 68.73%, 19.64%, and 11.64% in cases, and 71.71%, 24.30%, and 3.98% in healthy controls, respectively. The average frequency of the MTHFR 677T allele was 21.45% among the cases compared to 16.13% among the controls. In the present case-control study we have observed a higher frequency of the MTHFR 677TT genotype in cases of leukaemia (AML, ALL, CML and CLL) as compared with controls; this might be due to ethnic and geographic variation. As per our findings, although the frequency of the MTHFR 677T allele is moderately high in AML, ALL and CLL, no statistically significant association was found; on the other hand statistically significant association was found in the context of CML cases. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. [Association between methylene-tetrahydrofolate reductase gene polymorphisms and chronic myeloid leukemia].

    PubMed

    Dorgham, Samia; Aberkane, Meriem; Boughrara, Wefa; Antar Soltan, Badra; Mehalhal, Nemra; Touhami, Hadj; Sidimansour, Noureddine; Merad Boudia, Nadia; Louhibi, Lotfi; Boudjema, Abdallah

    2014-09-01

    Methylene-tetrahydrofolate reductase (MTHFR) is a key enzyme of folate metabolism. Few studies were reported about its relationship with chronic myeloid leukemia (CML). We conducted a case-control study analyzing the prevalence of the polymorphisms MTHFR C677T and MTHFR A1298C in Algerians CML patients. Using TaqMan(®) allelic discrimination assay, we investigate MTHFR C677T and A1298C polymorphism distribution in 90 cases of CML and 100 healthy subjects. The frequencies of 677T alleles and genotypes 677TT and 677CT were significantly higher in cases than in control (P = 1E-6; OR = 6.77 [4.22-10.86]) and (P = 1E-6; OR = 10.38 [4.56-23.6]) respectively. Also, the frequencies of 1298C alleles and genotypes 1298CC and 1298AC were higher in cases (P = 9 E-6; OR = 2.65 [1.71-4.10]) and (P = 0.008; OR = 2.22 [1.21-4.06]) respectively. We report also the higher significance of the haplotype 677T/1298A and 677T/1298C in cases (P = 0.007; OR = 2.57 [1.26-5.24]) and (P = 5 E-6, OR = 6.91 [2.7646-17.2899]) respectively. Our results demonstrate that 677T and 1298C alleles are both associated with an increased risk of CML in Algeria.

  1. [Polymorphisms of methylenetetrahydrofolate reductase C677T and the risk of stomach cancer].

    PubMed

    Gao, Changming; Wu, Jianzhong; Ding, Jianhua; Liu, Yanting; Zang, Yu; Li, Suping; Su, Ping; Hu, Xu; Xu, Tianliang; Toshiro, Takezaki; Kazuo, Tajima

    2002-08-01

    In order to study the relation between polymorphisms of methylenetetrahydrofolate reductase C677T (MTHFR) and susceptibility of stomach cancer (SC). We conducted a case-control study with 107 cases of SC and 200 population-based controls in Huaian city of Jiangsu province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects. MTHFR genotypes were detected by PCR-RFLP method. (1) The frequency of MTHFR variant genotypes (C/T + T/T) among the cases (79.4%) was significantly higher than the controls (68.5%) (P = 0.041 6); the crude OR for SC was 1.78 (95% CI: 0.99 - 3.22). After adjustment for sex and age, the OR for SC was 1.89 (95% CI: 1.08 - 3.32). (2) Subjects who had MTHFR variant genotypes and having smoking habit were at a significantly higher risk of developing SC (OR = 7.72, 95% CI: 2.23 - 26.79) compared with those who had wild-type homozygotes (C/C) genotype and no smoking habit. Individuals who had variant genotypes and who had habit of frequent alcohol drinking were at an increased risk of developing SC (OR = 3.08, 95% CI: 1.30 - 7.23) compared with those with C/C genotype and low consumption of alcohol. As compared with subjects with C/C genotype and low consumption of alcohol and no smoking habit, individuals who had variant genotypes and who had habits of frequent alcohol drinking and smoking had 12.96 (95% CI: 2.76 - 70.46) folds risk developing SC. These results in the present study suggested that the polymorphisms of MTHFR C677T was associated with risk of developing SC, and there was a coordinated effect between MTHFR genotypes and habits of smoking and alcohol drinking in the development of SC.

  2. Association of Blood Lead Levels with Methylenetetrahydrofolate Reductase Polymorphisms among Chinese Pregnant Women in Wuhan City

    PubMed Central

    Shen, Wei; Zhang, Bin; Liu, Shuyun; Wu, Hongling; Gu, Xue; Qin, Lingzhi; Tian, Ping; Zeng, Yun; Ye, Linxiang; Ni, Zemin; Wang, Qi

    2015-01-01

    Background Pregnancy is an important stimulus of bone lead release. Elevated blood lead levels (BLLs) may cause adverse pregnancy outcomes for mothers and harmful lead effects on fetuses. However, the reports about maternal BLL changes during pregnancy are conflicting to some extent. This article is to explore the variations in BLLs among pregnant women. The relationships of BLLs with methylenetetrahydrofolate reductase (MTHFR) gene C677T, A1298C, and G1793A polymorphisms, which are associated with bone resorption, were also studied. A total of 973 women, including 234, 249, and 248 women in their first, second, and third trimesters, respectively, and 242 non-pregnant women, were recruited at the Wuhan Women and Children Medical Health Center. Methods BLLs were determined using a graphite furnace atomic absorption spectrometer. Single-nucleotide polymorphisms of MTHFR were identified with the TaqMan probe method. Results The geometric mean (geometric standard deviation) of BLLs was 16.2 (1.78) μg/L for all participants. All the studied MTHFR alleles were in Hardy-Weinberg equilibrium. Multiple-linear regression analysis revealed the following results. Among the pregnant women, those that carried MTHFR 677CC (i.e. wild-genotype homozygote) and 1298CC (i.e. mutant-genotype homozygote) exhibited higher BLLs than those that carried 677CT/TT (standardized β = 0.074, P = 0.042) and 1298AC/AA (standardized β = 0.077, P = 0.035) when other covariates (e.g., age, no. of children, education and income, etc.) were adjusted. The BLLs of pregnant women consistently decreased during the pregnancy and these levels positively correlated with BMI (standard β = 0.086–0.096, P<0.05). Conclusions The 1298CC mutant-type homozygote in the MTHFR gene is a risk factor for high BLLs among low-level environmental lead-exposed Chinese pregnant women, whose BLLs consistently decreased during gestation. PMID:25723397

  3. Methylenetetrahydrofolate reductase gene C677T polymorphism and breast cancer risk: Evidence for genetic susceptibility

    PubMed Central

    Kumar, Pradeep; Yadav, Upendra; Rai, Vandana

    2015-01-01

    There are several evidences supporting the role of 5–10 methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms in breast cancer (BC). Case control association studies on breast cancer have been repeatedly performed over the last two decades, but results are inconsistent. We performed a meta-analysis to confirm the association between MTHFR C677T polymorphism and BC risk. The articles were retrieved by searching the PubMed, Google Scholar, and Springer Link databases. Crude odds ratios (OR) with 95% confidence intervals (CIs) was used to assess the strength of association between C677T polymorphism and BC. Publication bias was assessed by Egger's and Begg-Mazumdar tests. Meta-analysis was performed with Open Meta Analyst. Total 75 studies with 31,315 cases and 35, 608 controls were found suitable for the inclusion in the present meta-analysis. The results of meta-analysis suggested that there were moderate significant association between C677T polymorphism and BC risk using overall comparisons in five genetic models (T vs. C: OR = 1.08, 95% CI = 1.03–1.13, p = < 0.001; TT + CT vs. CC: OR = 1.06, 95% CI = 1.02–1.09, p = < 0.001; TT vs. CC: OR = 1.17, 95% CI = 1.06–1.28, p = 0.001; CT vs. CC OR = 1.05, 95% CI = 1.01–1.08, p = 0.005; TT vs. CT + CC: OR = 1.12, 95% CI = 1.03–1.22, p = 0.005). In conclusion, results of present meta-analysis showed modest association between MTHFR C677T polymorphism with breast cancer in total studies. However, sub-group analysis results based on ethnicity showed strong significant association between TT genotype and breast cancer (TT vs. CC; OR°=°1.26; 95% CI: 1.06–1.51; p = 0.009) in Asian population but in Caucasian population such association was not observed (TT vs. CC; OR°=°1.08; 95% CI: 0.99–1.14; p = 0.05). PMID:26629412

  4. Methylenetetrahydrofolate reductase gene C677T polymorphism and breast cancer risk: Evidence for genetic susceptibility.

    PubMed

    Kumar, Pradeep; Yadav, Upendra; Rai, Vandana

    2015-12-01

    There are several evidences supporting the role of 5-10 methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms in breast cancer (BC). Case control association studies on breast cancer have been repeatedly performed over the last two decades, but results are inconsistent. We performed a meta-analysis to confirm the association between MTHFR C677T polymorphism and BC risk. The articles were retrieved by searching the PubMed, Google Scholar, and Springer Link databases. Crude odds ratios (OR) with 95% confidence intervals (CIs) was used to assess the strength of association between C677T polymorphism and BC. Publication bias was assessed by Egger's and Begg-Mazumdar tests. Meta-analysis was performed with Open Meta Analyst. Total 75 studies with 31,315 cases and 35, 608 controls were found suitable for the inclusion in the present meta-analysis. The results of meta-analysis suggested that there were moderate significant association between C677T polymorphism and BC risk using overall comparisons in five genetic models (T vs. C: OR = 1.08, 95% CI = 1.03-1.13, p = < 0.001; TT + CT vs. CC: OR = 1.06, 95% CI = 1.02-1.09, p = < 0.001; TT vs. CC: OR = 1.17, 95% CI = 1.06-1.28, p = 0.001; CT vs. CC OR = 1.05, 95% CI = 1.01-1.08, p = 0.005; TT vs. CT + CC: OR = 1.12, 95% CI = 1.03-1.22, p = 0.005). In conclusion, results of present meta-analysis showed modest association between MTHFR C677T polymorphism with breast cancer in total studies. However, sub-group analysis results based on ethnicity showed strong significant association between TT genotype and breast cancer (TT vs. CC; OR°=°1.26; 95% CI: 1.06-1.51; p = 0.009) in Asian population but in Caucasian population such association was not observed (TT vs. CC; OR°=°1.08; 95% CI: 0.99-1.14; p = 0.05).

  5. Association of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with primary glaucoma in Saudi population.

    PubMed

    Al-Shahrani, Hamoud; Al-Dabbagh, Najwa; Al-Dohayan, Nourah; Arfin, Misbahul; Al-Asmari, Mohammad; Rizvi, Sadaf; Al-Asmari, Abdulrahman

    2016-09-01

    Methylenetetrahydrofolate reductase (MTHFR), a critical enzyme in folate metabolism is involved in DNA synthesis, DNA repair and DNA methylation. The functional polymorphism of MTHFR gene, C677T has been shown to impact various diseases and implicated as a risk factor for the development of various neurodegenerative disorders including glaucoma. We investigated MTHFR C677T genotypes and alleles frequencies in primary glaucoma [primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG)] patients and matched healthy controls in a case-control study. Two hundred ten primary glaucoma cases were studied for MTHFR C677T polymorphism and compared with 280 controls taken from the healthy population, employing the polymerase chain reaction-restriction fragment length polymorphism technique (PCR-RFLP). The MTHFR gene was amplified using specific primers. The PCR products (294 bp) was subsequently digested with HinfI (New England Biolabs) at 37 °C for 12 h, separated by electrophoresis on 2 % agarose gels, and visualized with ethidium bromide staining. The restriction digestion yielded 168 and 126 bp fragments for TT, 294, 168 and 126 bp fragments for CT and undigested PCR product 294 bp indicating CC genotype. We found the frequency of the genotypes and alleles of MTHFR C677T differ significantly between cases and controls. The frequencies of allele T and genotype CT were significantly higher while the frequencies of allele C and genotype CC were lower in primary glaucoma patients as compared to controls (p <0.05). Upon stratification of our results into POAG and PACG, significantly higher frequencies of allele T (19.44 %) and genotype CT (38.89 %) were found in POAG patients compared to controls (12.5 % and 25 % respectively). The frequencies of alleles and genotypes were almost similar in PACG and controls (p = 0.8). This study indicates that the allele T and genotype CT of MTHFR C677T polymorphism are significantly associated with POAG

  6. Methionine synthase A2756G polymorphism may predict ulcerative colitis and methylenetetrahydrofolate reductase C677T pancolitis, in Central China

    PubMed Central

    Chen, Min; Peyrin-Biroulet, Laurent; Xia, Bing; Guéant-Rodriguez, Rosa-Maria; Bronowicki, Jean-Pierre; Bigard, Marc-André; Guéant, Jean-Louis

    2008-01-01

    Background The association of genetic polymorphisms related to metabolism of homocysteine with inflammatory bowel disease has been evidenced in Crohn disease and remains an open question in ulcerative colitis. We evaluated the association of the polymorphisms of MTHFR, MTR, MTRR and TCN2 genes with ulcerative colitis in Central China. Methods 168 patients were genotyped for these polymorphisms and compared to 219 matched controls. Results Methionine synthase 2756G allele frequency was higher in ulcerative colitis than in controls 0.15 (95% C.I. 0.11–0.19) vs 0.09 (95% C.I. 0.07 – 0.12), (P = 0.0137) and predicted ulcerative colitis risk in logistic regression, with an Odds ratio at 1.8 (95% C.I. 1.15–2.84). Methylenetetrahydrofolate reductase 677TT genotype was 2.7-fold more prevalent in individuals with pancolitis than in those with left colitis or proctitis, with respective percentages of 27.3 (95% C.I.16.4–42.0) and 10.5 (95% C.I. 6.3–17.1) (P = 0.0123). The carriage of 677TT or 677CT/1298AC genotypes of methylenetetrahydrofolate reductase was more frequent in cases with pancolitis than in subjects with left colitis or proctitis (P = 0.0048), with an Odds ratio adjusted by age and sex at 3.3 (95% C.I. 1.4–7.9), P = 0.0084) in logistic regression. Conclusion Methionine synthase and methylenetetrahydrofolate reductase are genes of vitamin B12 and folate cellular metabolism associated respectively with risk and extent of ulcerative colitis, at least in Central China. This finding may open new insights, particularly for the potential interest in treating patients carrying the 677TT MTHFR genetic trait and a deficit in folate. PMID:18700049

  7. Relationship between genetic polymorphisms of methylenetetrahydrofolate reductase and breast cancer chemotherapy response.

    PubMed

    Yang, L; Wang, X W; Zhu, L P; Wang, H L; Wang, B; Wu, T; Zhao, Q; JinSiHan, D L X T; Wang, X Y

    2016-09-23

    Activity of methylenetetrahydrofolate reductase (MTHFR), an enzyme involved in folate metabolism, is influenced by mutations in the corresponding gene, contributing to a decrease in 5,10-MTHF. Due to such polymorphisms, individuals differ in MTHFR enzyme activity and plasma folate levels. We investigated the relationship between two common MTHFR polymorphisms (C677T and A1298C) and breast cancer (BC) chemotherapy response. From February 2013 to January 2016, 148 advanced BC patients at the Center Hospital of Cangzhou were enrolled and treated with six different chemotherapy regimens. Subjects were genotyped using polymerase chain reaction-restriction fragment length polymorphism. Forty-one (27.7%), 70 (47.3%), and 37 (25.0%) patients carried the C/C, C/T, and T/T C677T genotypes, respectively; 101 (68.2%), 42 (28.4%), and 5 (3.4%) had the A/A, A/C, and C/C genotypes of A1298C, respectively. Total chemotherapy efficacy was 66.9% (99/148), with 7 (4.7%), 92 (62.2%), 36 (24.3%), and 13 (8.8%) cases showing complete response, partial response, no change, and progressive disease, respectively. Chemotherapy regimens did not differ in effectiveness (P > 0.05). Efficacy rates associated with C677T C/C, C/T, and T/T genotypes were 58.5, 58.6, and 91.9%, respectively, with T/T carriers exhibiting significantly better responses than the C/C (P < 0.05) and C/T groups (P < 0.05). Effectiveness among A1298C A/A, A/C, and C/C carriers was 70.6, 64.3, and 0.0%, respectively, but no difference was established between these genotypes in this regard (P > 0.05). The MTHFR C677T genotype may be associated with BC chemotherapy response, and could be of great value in guiding individualized treatment for this disease.

  8. [Polymorphism of methylenetetrahydrofolate reductase and sensitivity of stomach cancer to fluoropyrimidine-based chemotherapy].

    PubMed

    Gao, Chang-Ming; Lu, Jian-Wei; Toshiro, Takezaki; Wu, Jian-Zhong; Cao, Hai-Xia; Chen, Huan-Qiu; Feng, Ji-Feng; Kazuo, Tajima

    2004-12-01

    To investigate the relationship between polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) C677T or A1298C and the response to fluoropyrimidine (5-FU)-based chemotherapy in advanced stomach cancer (SC). 75 cases with advanced SC were analyzed. All patients were treated with 5-FU-based chemotherapy and DNA of peripheral blood leukocytes was obtained before therapy. MTHFR genotypes were detected by PCR-RFLP method. (1) Of all the cases, the frequencies of MTHFR C677T C/C, C/T and T/T genotype were 32.0%, 44.0% and 24.0%, while the frequencies of MTHFR A1298C A/A, A/C and C/C genotype were 69.3%, 29.3% and 1.3%, respectively. The overal response rate to 5-FU-based chemotherapy was 29.3%. (2) The response rate to therapy among MTHFR C677T T/T genotype patients (83.3%) was significantly higher than the C677T C/T genotype (15.2%, chi(2) = 22.27, P = 0.000) or the C677T C/C genotype (8.3%, chi(2) = 23.44, P = 0.000). As compared with patients with C677T C allele, patients with C677T T/T genotype had a 7.64-fold sensitivity to 5-FU-based chemotherapy (adjusted for sex, age, prior adjuvant therapy and chemotherapy program, 95% CI: 3.14 - 18.62). The response rate to therapy among patients with MTHFR A1298C A/A genotype (36.5%) was significantly higher than patients with A1298C C allele (13.0%, chi(2) = 4.19, P = 0.041, adjusted OR = 3.75, 95% CI: 0.94 - 14.87). The response rate to therapy among patients with MTHFR C677T T/T and A1298C A/A genotypes (86.7%) was significantly higher than other groups of C677T and A1298C genotypes (15.0%, Fisher exact: P = 0.000, adjusted OR = 6.57, 95% CI: 2.8 - 15.6). (3) The incidence rates of nausea/vomiting in MTHFR C677T T/T, C/T or A1298C A/A genotypes were significantly higher than other genotypes, but the incidence rates of other treatment-related adverse reaction in MTHFR C677T or A1298C genotypes were not significantly different. These results in the present study suggested that the polymorphisms of MTHFR were

  9. Methylenetetrahydrofolate Reductase C677T Polymorphism and Recurrent Pregnancy Loss Risk in Asian Population: A Meta-analysis.

    PubMed

    Rai, Vandana

    2016-10-01

    The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene was implicated to be associated with thrombophilia due to its role in catalyzing the formation of 5-methylenetetrahydrofolate, a co-substrate for the conversion of homocysteine to methionine. Several case-control studies were investigated MTHFR C677T polymorphism as risk for recurrent pregnancy loss (RPL). These studies rendered contradictory results, some indicating that the polymorphism is associated with the risk of RPL whereas others concluded there is no association. To shed light on these inconclusive findings, a meta-analysis of all available studies published from Asian population relating the C677T polymorphism to the risk of RPL was conducted. The following electronic databases were searched without language restrictions: PubMed, Google Scholars, Elsevier and Springer Link up to December, 2015. Meta-analysis was performed using MetaAnalyst and Mix version 1.7. Meta-analysis results suggested that MTHFR C677T polymorphism contributed to the increased RPL risk in Asian population using all five genetic models (for T vs. C: OR 1.35, 95 % CI 1.09-1.68, p = 0.009; for TT + CT vs. CC: OR 1.44, 95 % CI 1.14-1.82, p = 0.006; for CT vs. CC: OR 1.39, 95 % CI 1.07-1.8, p = 0.01; for TT vs. CC: OR 1.79, 95 % CI 1.23.2.6, p = 0.007; for TT vs. CT + CC: OR 1.61, 95 % CI 1.02-2.56, p = 0.04). In conclusion, this meta-analysis demonstrates a strong association between the MTHFR C677T variant and RPL in Asian population and raising the importance of the use of folate in its treatment and prevention.

  10. Bladder exstrophy-epispadias complex and the role of methylenetetrahydrofolate reductase C677T polymorphism: A case control study

    PubMed Central

    Raman, Venkat Shankar; Bajpai, Minu; Ali, Abid

    2016-01-01

    Purpose: The Bladder Exstrophy-Epispadias Complex (BEEC) is the most serious form of midline abdominal malformation. The etiology of BEEC is unknown and is thought to be multifactorial. Methylenetetrahydrofolate reductase (MTHFR) polymorphism C677T is strongly associated with other midline abnormalities such as neural tube defects. No proper case-control study existed comparing MTHFR polymorphism with BEEC. We sought to find an association with MTHFR polymorphism and patients with bladder exstrophy (BE). Materials and Methods: The design of the study was a case-control study, involving 50 children with BEEC and 50 normal healthy school children. Genetic analysis for MTHFR 677 polymorphism was carried out after DNA extraction and polymerase chain reaction amplification. Epidemiological analysis was done by using the birth defect questionnaire on parents of BEEC. Results: Forty-two classical BE, two cloacal exstrophies (CE), four epispadias, and two exstrophy variant patients were a part of this study. Severe variety of BE had a significant association with C667T MTHFR polymorphism as compared to the normal control population (P = 0.01). Conclusion: C677T MTHFR polymorphism has a strong association with severe variety (CE) of BEEC occurrence. PMID:26862292

  11. Association of methylenetetrahydrofolate reductase (A1298C and C677T) polymorphisms with retinal vein occlusion in Tunisian patients.

    PubMed

    Mrad, Meriem; Wathek, Cheima; Saleh, Mekki Ben; Baatour, Makrem; Rannen, Riadh; Lamine, Khaled; Gabsi, Salem; Gritli, Nasreddine; Fekih-Mrissa, Najiba

    2014-04-01

    The role of two polymorphisms C677T and A1298C of the methylenetetrahydrofolate reductase (MTHFR) gene in the etiology of retinal vein occlusion (RVO) has not been adequately clarified. The aim of this study was to examine the prevalence of these polymorphisms among RVO Tunisian patients with and without systemic risk factors. Seventy-two patients with retinal vein occlusion (RVO) were studied. The control group included140 people matched for age, sex, and risk factors. Participants in the study were genotyped for the MTHFR C677T and A1298C polymorphisms. The genotyping was performed by PCR-RFLP. No significant differences were found in the frequencies of the three genotypes (AA, AC, CC) of the MTHFR A1298C polymorphism between RVO patients and healthy controls. However, the prevalence of the group of mutated genotypes (AC+CC) of the missense variant MTHFR A1298C was significantly different between patients and controls (16.67% vs. 6.42%, p=.01). Additionally, the frequency of the CT genotype as well as the group of combined mutated genotypes (CT+TT) for the C677T variant was significantly higher among RVO patients compared with controls (p<10(-3), p<10(-3)). This suggests an association between this polymorphism and RVO. Large study populations would be required to understand more completely the contribution of these markers in the risk of RVO.

  12. Meta-Prediction of the Effect of Methylenetetrahydrofolate Reductase Polymorphisms and Air Pollution on Alzheimer’s Disease Risk

    PubMed Central

    Wu, Suh-Mian; Chen, Zhao-Feng; Young, Lufei; Shiao, S. Pamela K.

    2017-01-01

    Background: Alzheimer’s disease (AD) is a significant public health issue. AD has been linked with methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, but the findings have been inconsistent. The purpose of this meta-predictive analysis is to examine the associations between MTHFR polymorphisms and epigenetic factors, including air pollution, with AD risk using big data analytics approaches. Methods and Results: Forty-three studies (44 groups) were identified by searching various databases. MTHFR C677T TT and CT genotypes had significant associations with AD risk in all racial populations (RR = 1.13, p = 0.0047; and RR = 1.12, p < 0.0001 respectively). Meta-predictive analysis showed significant increases of percentages of MTHFR C677T polymorphism with increased air pollution levels in both AD case group and control group (p = 0.0021–0.0457); with higher percentages of TT and CT genotypes in the AD case group than that in the control group with increased air pollution levels. Conclusions: The impact of MTHFR C677T polymorphism on susceptibility to AD was modified by level of air pollution. Future studies are needed to further examine the effects of gene-environment interactions including air pollution on AD risk for world populations. PMID:28085050

  13. Meta-Prediction of the Effect of Methylenetetrahydrofolate Reductase Polymorphisms and Air Pollution on Alzheimer's Disease Risk.

    PubMed

    Wu, Suh-Mian; Chen, Zhao-Feng; Young, Lufei; Shiao, S Pamela K

    2017-01-11

    Background: Alzheimer's disease (AD) is a significant public health issue. AD has been linked with methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, but the findings have been inconsistent. The purpose of this meta-predictive analysis is to examine the associations between MTHFR polymorphisms and epigenetic factors, including air pollution, with AD risk using big data analytics approaches. Methods and Results: Forty-three studies (44 groups) were identified by searching various databases. MTHFR C677T TT and CT genotypes had significant associations with AD risk in all racial populations (RR = 1.13, p = 0.0047; and RR = 1.12, p < 0.0001 respectively). Meta-predictive analysis showed significant increases of percentages of MTHFR C677T polymorphism with increased air pollution levels in both AD case group and control group (p = 0.0021-0.0457); with higher percentages of TT and CT genotypes in the AD case group than that in the control group with increased air pollution levels. Conclusions: The impact of MTHFR C677T polymorphism on susceptibility to AD was modified by level of air pollution. Future studies are needed to further examine the effects of gene-environment interactions including air pollution on AD risk for world populations.

  14. Risk of colorectal cancer associated with the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in the Kashmiri population.

    PubMed

    Sameer, A S; Shah, Z A; Nissar, S; Mudassar, S; Siddiqi, M A

    2011-06-21

    Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and is involved in DNA synthesis, DNA repair and DNA methylation. The two common functional polymorphisms of MTHFR, 677 C→T and 1298 A→C, have been shown to impact various diseases, including cancer. The 677 C→T polymorphism has been widely investigated in different cancers and has been implicated as a risk factor for the development of various cancers. We investigated MTHFR C677T genotype frequency in colorectal cancer cases in the Kashmiri population and correlated this information with the known clinicopathological characters of colorectal cancer, in a case-control study. Eighty-six colorectal cancer cases were studied for MTHFR C677T polymorphism, compared to 160 controls taken from the general population, employing the PCR-RFLP technique. We found the frequency of the three different genotypes of MTHFR in our ethnic Kashmir population, i.e., CC, CT and TT, to be 68.6, 20.9 and 10.4% among colorectal cancer cases and 75.6, 16.9 and 7.5% among the general control population, respectively. There was a significant association between the MTHFR TT genotype and colorectal cancer in the higher age group. We conclude that the MTHFR C677T polymorphism slightly increases the risk for colorectal cancer development in our ethnic Kashmir population.

  15. A Meta-Analysis of Association between Methylenetetrahydrofolate Reductase Gene (MTHFR) 677C/T Polymorphism and Diabetic Retinopathy.

    PubMed

    Luo, Shasha; Wang, Furu; Shi, Chao; Wu, Zhifeng

    2016-08-10

    To shed light on the conflicting findings of the association between the methylenetetrahydrofolate reductase gene (MTHFR) 677C/T polymorphism and the risk of diabetic retinopathy (DR), a meta-analysis was conducted. A predefined search was performed on 1747 DR cases and 3146 controls from 18 published studies by searching electronic databases and reference lists of relevant articles. A random-effects or fixed-effects model was used to estimate the sizes of overall and stratification effects of the MTHFR 677C/T polymorphism on the risk of DR, as appropriate. Risks were evaluated by odds ratios (OR) with 95% confidence intervals (95% CI). We found a significant association between the MTHFR 677C/T polymorphism and the risk of DR for each genetic model (recessive model: OR = 1.67; 95% CI: 1.19-2.40 and dominant model: OR = 1.71; 95% CI: 1.28-2.28; respectively). In stratified analysis; we further found that the Asian group with both types of diabetes mellitus (DM) showed a significant association with genetic models (recessive model: OR = 2.16; 95% CI: 1.75-2.60 and dominant model: OR = 1.98; 95% CI: 1.42-2.76; respectively). Our study suggested that the MTHFR 677C/T polymorphism may contribute to DR development, especially in Asian populations. Prospective and additional genome-wide association studies (GWAS) are needed to clarify the real role of the MTHFR gene in determining susceptibility to DR.

  16. Impact of methionine synthase gene and methylenetetrahydrofolate reductase gene polymorphisms on the risk of sudden sensorineural hearing loss.

    PubMed

    Gross, Menachem; Friedman, Gideon; Eliashar, Ron; Koren-Morag, Nira; Goldschmidt, Neta; Atta, Iman Abou; Ben-Yehuda, Arie

    2006-01-01

    Idiopathic sudden sensorineural hearing loss (SSNHL) represents a frequently encountered otological disease of unknown etiology. In recent years, several inherited risk factors have been found in the pathogenesis of vascular diseases. In the present study, we determined whether specific polymorphism or the combination of polymorphisms in folate-dependent homocysteine metabolism genes can act as predisposing inherited vascular risk factors in the development of SSNHL. We conducted a prospective case-control study using DNA samples extracted from 81 patients diagnosed as suffering from SSNHL and 264 healthy control subjects. Three functional polymorphisms were analyzed by polymerase chain reaction amplification, restriction enzyme digestion, and DNA fragment separation by electrophoresis: methylenetetrahydrofolate reductase (MTHFR) C677T, MTHFR A1298C, and methionine synthase (MTR) A2756G polymorphisms. The prevalence of the homozygous genotype of MTR 2756GG in the SSNHL patients (9%) was significantly higher than in the control group (4%) (p = 0.011). The allelic frequency of the G allele of the MTR A2756G polymorphism among SSNHL patients (12.5%) was also significantly higher than in the control group (5%) (p = 0.033). The prevalence of patients possessing two polymorphisms (31%) and three polymorphisms (17%) in the SSNHL group was significantly higher than in the control group (23 and 9%, respectively; p = 0.019). The frequency of patients with a very high rank risk (double homozygous) was significantly higher in the SSNHL group, MTHFR 677TT/MTR 2675GG--7%, than the frequency of patients in the control group, MTHFR 677TT/MTR 2675GG--3% (p = 0.030). Certain polymorphisms in genes encoding enzymes in the folate-dependent homocysteine metabolism are associated with SSNHL. In our case-control study, a significant association between MTR 2756GG genotype and SSNHL was found which may represent an inherited vascular risk factor in the pathogenesis of SSNHL.

  17. Methylenetetrahydrofolate reductase C677T polymorphism and Factor V Leiden variant in Mexican women with preeclampsia/eclampsia.

    PubMed

    Dávalos, I P; Moran, M C; Martínez-Abundis, E; González-Ortiz, M; Flores-Martínez, S E; Machorro, V; Sandoval, L; Figuera, L E; Mena, J P; Oliva, J M; Tlacuilo-Parra, J A; Sánchez-Corona, J; Salazar-Páramo, M

    2005-01-01

    The etiology of preeclampsia is still a matter of controversy. An association between hyperhomocysteinemia and preeclamptic patients has been described. A common missense mutation in the methylenetetrahydrofolate reductase (MTHFR) gene is associated with increased plasma homocysteine concentrations. In addition, the polymorphism of gene encoding for Factor V Leiden G1691A is associated with a prothrombotic state in heterozygous subjects. Both mutations in these thrombophilic proteins appear to have different prevalence in the general population and in patients with preeclampsia/eclampsia (PE/E). We studied single nucleotide polymorphisms for MTHFR C677T and coagulation Factor V Leiden in 33 Mexican patients with PE/E as a genetic risk factor for these diseases, comparing with a normotensive pregnant control group. The genotype and allele frequencies of MTHFR C677T and Factor V Leiden mutations between Mexican women with PE/E and healthy controls were not different. We conclude that these polymorphisms do not contribute in the etiology of PE/E as it has been reported in other populations.

  18. Methylenetetrahydrofolate reductase genetic polymorphisms and esophageal squamous cell carcinoma susceptibility: A meta-analysis of case-control studies

    PubMed Central

    Shujuan, Yang; Jianxing, Zhang; Xin-yue, Chen

    2013-01-01

    Objectives: Genetic factors and environmental factors play a role in pathogenesis of esophageal squamous cell carcinoma (ESCC). Previous studies regarding the association of folate intake and Methylenetetrahydrofolate reductase C677T polymorphism with ESCC was conflicting. We conducted a meta-analysis to investigate the association of MTHFR C677T and folate intake with esophageal cancer risk. Methodology: MEDLINE, EMBASE and the Chinese Biomedical Database were searched in our study. The quality of studies were evaluated by predefined scale, and The association of polymorphisms of MTHFR C677T and folate intake and ESCC risk was estimated by Odds ratio (ORs) with 95% confidence intervals (CIs). Results: Nineteen studies (4239 cases and 5575 controls) were included for meta-analysis. A significant association was seen between individuals with MTHFR 677 CT [OR(95%)=1.47(1.32-1.63)] and TT [OR(95%)=1.69(1.49-1.91)] genotypes and ESCC risk (p<0.05). Low intake of folate had significantly higher risk of esophageal cancer among individuals with CT/TT genotype [OR(95%)=1.65(1.1-2.49)], while high intake of folate did not find significant high risk of esophageal cancer among individuals with CT/TT genotype [OR(95%)=1.64 (0.82-3.26)]. Conclusions: Our meta-analysis indicated the folate intake and MTHFR 677CT/TT are associated with the risk of ESCC, and folate showed a significant interaction with polymorphism of MTHFR C677T. PMID:24353609

  19. Methylenetetrahydrofolate Reductase C677T and A1298C Polymorphisms in Male Partners of Recurrent Miscarriage Couples

    PubMed Central

    Tara, Somayeh-Sadat; Ghaemimanesh, Fatemeh; Zarei, Saeed; Reihani-Sabet, Fakhreddin; Pahlevanzadeh, Zhamak; Modarresi, Mohammad Hosein; Jeddi-Tehrani, Mahmood

    2015-01-01

    Background: Methylenetetrahydrofolate reductase (MTHFR) single-nucleotide polymorphisms (SNPs) C677T and A1298C have been described as strong risk factors for idiopathic recurrent miscarriage (RM). However, very few studies have investigated the association of paternal MTHFR SNPs with RM. The aim of the present study was to evaluate the prevalence of paternal C677T and A1298C SNPs among Iranian RM couples. Methods: The study subjects comprised 225 couples with more than three consecutive pregnancy losses, and 100 control couples with no history of pregnancy complications. All females in the case group had MTHFR polymorphisms; and genotype SNPs were analyzed by PCR-RFLP. Groups were statistically compared using Mann Whitney U-test and Chi-square statistical tests. The p<0.05 were considered significant. Results: Statistically significant difference was detected in the frequency of MTHFR SNPs in male partners of the two groups (p=0.019). Combined heterozygosity of MTHFR polymorphisms was a common phenomenon in the males; 52 (23.1%) and 14 (14%) of males in RM and control groups, respectively. Absence of combined homozygosity for both SNPs in all studied groups/genders was observed. Conclusion: The MTHFR gene composition of male partners of RM couples may contribute to increased risk of miscarriage. PMID:27110516

  20. The relationship between methylenetetrahydrofolate reductase C677T gene polymorphism and diabetic nephropathy in Croatian type 2 diabetic patients.

    PubMed

    Tomić, Nives Gojo; Marusić, Srećko; Bozikov, Velimir; Kusec, Rajko; Bacić-Vrca, Vesna; Tadić, Mario

    2013-09-01

    Methylenetetrahydrofolate reductase (MTHFR) polymorphism has been shown to be associated with the development of diabetic nephropathy in many ethnic groups. In this study, we examined the correlation between MTHFR C677T polymorphism and microalbuminuria in patients with diabetes mellitus type 2 in Croatian patients. 85 patients with diabetes mellitus type 2 were recruited. Patients were classified into two groups--with and without diabetic nephropathy according to urinary albumin excretion rate in urine collected during 24 hours. The C677T genotype was determined by real-time PCR analysis. The genotype frequencies were CC 36.5%, CT 42.3% and TT 21.2% in diabetic patients without nephropathy versus CC 39.4%, CT 45.4% and TT 15.2% in those with nephropathy. There was no statistically significant difference in allele distribution between patients with nephropathy and those without (p = 0.788). Our study did not show a correlation between mutations in the MTHFR gene and diabetic nephropathy in Croatian patients. Diabetic nephropathy is influenced by multiple risk factors which can modify the importance of MTHFR polymorphism in its development.

  1. Methylenetetrahydrofolate Reductase A1298C Polymorphism and Breast Cancer Risk: A Meta-analysis of 33 Studies

    PubMed Central

    Rai, V

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) enzyme is essential for DNA synthesis and DNA methylation, and its gene polymorphisms have been implicated as risk factors for birth defects, neurological disorders, and different types of cancers. Several studies have investigated the association between the MTHFR A1298C polymorphism and breast cancer (BC) risk, but the results were inconclusive. To assess the risk associated with MTHFR A1298C polymorphism, a comprehensive meta-analysis was performed. PubMed, Google Scholar, Elsevier and Springer Link databases were searched for case-control studies relating the association between MTHFR A1298C polymorphism and BC risk and estimated summary odds ratios (ORs) with confidence intervals (CIs) for assessment. Up to January 2014, 33 case-control studies involving 15,919 BC patients and 19,700 controls were included in the present meta-analysis. The results showed that the A1298C polymorphism was not associated with BC risk in all the five genetic models (C vs. A allele (allele contrast): OR = 0.99, 95% confidence interval (CI): 0.93–1.05; AC versus AA (heterozygote/codominant): OR = 0.97, 95% CI: 0.89–1.04; CC versus AA (homozygote): OR = 0.99, 95% CI: 0.91–1.06; CC + AC versus AA (dominant model): OR = 0.97, 95% CI: 0.90–1.05; and CC versus AC + AA (recessive model): OR = 0.99, 95% CI: 0.91–1.07). The present meta-analysis did not support any association between the MTHFR A1298C polymorphism and BC risk. PMID:25506474

  2. Methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and susceptibility to Parkinson's disease: a meta-analysis.

    PubMed

    Wu, Yi-Le; Ding, Xiu-Xiu; Sun, Ye-Huan; Yang, Hui-Yun; Sun, Liang

    2013-12-15

    The association between the methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and susceptibility to Parkinson's disease (PD) was controversial in previous studies. The present study was therefore designed to investigate a more reliable estimate. 15 studies were identified by a search of PubMed, EBMBASE, PDGENE, Elsevier, Springer Link, CBM (Chinese Biomedical Database), CNKI (Chinese National Knowledge Infrastructure), VIP (Chinese), and Wanfang (Chinese) databases, up to April 2013. Odds ratios (ORs) with corresponding 95% confidence interval (CI) were calculated using fixed effects model or random effects model. The subgroup analyses were made on the ethnicity. MTHFR C677T polymorphism had a significant association with susceptibility to PD in all genetic models (for T vs. C: OR=1.24, 95% CI=1.11-1.38; for TT+CT vs. CC: OR=1.27, 95% CI=1.10-1.46; for TT vs. CC: OR=1.56, 95% CI=1.22-1.98; for TT vs. CT+CC: OR=1.43, 95% CI=1.14-1.79). Subgroup analyses by ethnicity revealed that the association between the MTHFR C677T polymorphism and PD existed in Caucasian population and Asian population. However, no association was detected between the MTHFR A1298C polymorphism and PD. Results from this meta-analysis supported that the MTHFR C677T polymorphism was associated with an increased risk of PD. The MTHFR A1298C polymorphism may not increase the susceptibility to PD. Further studies are required to confirm our findings. © 2013.

  3. Impact of methylenetetrahydrofolate reductase (MTHFR) polymorphisms on methotrexate-induced toxicities in acute lymphoblastic leukemia: a meta-analysis.

    PubMed

    Yang, Lin; Hu, Xin; Xu, Luhang

    2012-10-01

    The associations between methylenetetrahydrofolate reductase (MTHFR) polymorphism and methotrexate (MTX)-induced toxicities in patients with acute lymphoblastic leukemia (ALL) have been evaluated in various populations, with the results remained conflicting. Therefore, we conducted a meta-analysis by combining available data to derive a more precise estimation of the association. PubMed, Embase, and China National Knowledge Infrastructure were searched until 21 September 2011 to identify eligible studies. A total of 14 studies were included, with all studies investigating MTHFR C677T polymorphism while nine of them investigating MTHFR A1298C polymorphism only. Results suggested that MTHFR C677T polymorphism was associated with significantly increased risk of MTX-induced toxicity, specifically liver toxicity (TT/CT vs. CC: odds ratio (OR) = 1.70, 95 % confidence interval (CI) = 1.05-2.75), myelosuppression (TT vs. CT/CC: OR = 2.82, 95 %CI = 1.25-6.34), oral mucositis (TT/CT vs. CC: OR = 3.68, 95 %CI = 1.73-7.85), gastrointestinal toxicity (TT/CT vs. CC: OR = 2.36, 95 %CI = 1.36-4.11), and skin toxicity (T vs. C: OR = 2.26, 95 %CI = 1.07-4.74). MTHFR A1298C polymorphism was found to be associated with decreased risk of skin toxicity (CC/AC vs. AA: OR = 0.11, 95 %CI = 0.01-0.85). Genotyping of MTHFR polymorphism, C677T particularly, prior to treatment for ALL is likely to be useful with the aim of tailoring MTX therapy and thus reducing the MTX-related toxicities. However, further studies with larger data set and well-designed models are required to validate our findings.

  4. Relationship between methylenetetrahydrofolate reductase (MTHFR) A1298C gene polymorphism and type 2 diabetic nephropathy risk: a meta-analysis.

    PubMed

    Zhang, Jie; Xiao, Yan; Zhang, Xian-Wen; Gao, Zhi-Qing; Han, Jing-Hui

    2014-07-01

    Relationship between methylenetetrahydrofolate reductase (MTHFR) A1298C gene polymorphism and type 2 diabetic nephropathy (T2DN) risk is still unclear. This study was performed to evaluate if there is an association between the MTHFR A1298C gene polymorphism and T2DN risk using meta-analysis. The relevant reports were searched and identified from PubMed, Cochrane Library on 1 October 2013, and eligible studies were included and synthesized. Eight reports were recruited into this meta-analysis for the association of the MTHFR A1298C gene polymorphism with T2DN risk. The MTHFR A1298C C allele or CC genotype was shown to be not associated with T2DN risk (C allele: OR = 0.76, 95% CI: 0.43-1.34, p = 0.34; CC genotype: OR = 1.18, 95% CI: 0.63-2.22, p = 0.60). Interestingly, AA genotype was associated with the T2DN risk (OR = 0.68, 95% CI: 0.49-0.96, p = 0.03). In the sensitivity analysis according to the Hardy-Weinberg equilibrium (HWE), the results were consistent with those in non-sensitivity analysis. However, in the sensitivity analysis according to the control source from hospital, sample size of case (≥ 100), sample size of case (<100), the MTHFR A1298C gene polymorphism was not associated with T2DN risk. In conclusion, the MTHFR A1298C gene polymorphism was not associated with T2DN risk. However, additional studies are required to firmly establish a correlation between the MTHFR A1298C gene polymorphism and T2DN risk.

  5. Diet folate, DNA methylation and polymorphisms in methylenetetrahydrofolate reductase in association with the susceptibility to gastric cancer.

    PubMed

    Gao, Shang; Ding, Li-Hong; Wang, Jian-Wei; Li, Cun-Bao; Wang, Zhao-Yang

    2013-01-01

    Methylenetetrahydrofolate reductase (MTHFR) has been reported to be associated with DNA methylation, an epigenetic feature frequently found in gastric cancer. We conducted a case-control study to explore the association of MTHFR C677T polymorphisms with gastric cancer risk and its relation with the DNA methylation of COX-2, MGMT, and hMLH1 genes. Genotyping of P16, MGMT and HMLH1 was determined by methylation-specific PCR after sodium bisulfate modification of DNA, and genotyping of MTHFR C677T was conducted by TaqMan assays using the ABI Prism 7911HT Sequence Detection System. Folate intake was calculated with the aid of a questionnaire. Compared with the MTHFR 677CC genotype, the TT genotype was significantly associated with 2.08 fold risk of gastric cancer when adjusting for potential risk factors. Individuals who had an intake of folate above 310 μg/day showed protective effects against gastric cancer risk. The effect of MTHFR C677T polymorphisms on the risk of gastric cancer was modified by folate intake and methylation status of MGMT (P for interaction <0.05).

  6. Polymorphisms of 5,10-methylenetetrahydrofolate reductase and thymidylate synthase, dietary folate intake, and the risk of leukemia in adults.

    PubMed

    Liu, Ping; Zhang, Min; Xie, Xing; Jin, Jie; Holman, C D'Arcy J

    2016-03-01

    The 5,10-methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TS) are critical enzymes in folate metabolism. Previous studies have reported conflicting results on the associations between MTHFR/TS polymorphisms and adult leukemia risk, which may due to the lack of information on folate intake. We investigated the risks of adult leukemia with genetic polymorphisms of folate metabolic enzymes (MTHFR C677T, A1298C, and TS) and evaluated if the associations varied by dietary folate intake from a multicenter case-control study conducted in Chinese. This study comprised 442 incident adult leukemia cases and 442 outpatient controls, individually matched to cases by gender, birth quinquennium, and study site. Genotypes were determined by a polymerase chain reaction (PCR) or PCR-based restriction fragment length polymorphism assay. Dietary folate intake was assessed by face-to-face interviews using a validated food-frequency questionnaire. The MTHFR 677TT genotype conferred a significant higher risk of leukemia in males than in females and exhibited an increased risk of acute myeloid leukemia (AML) but a decreased risk of acute lymphoblastic leukemia (ALL). The MTHFR 1298AC genotype appeared to decrease the risks of leukemia in both genders, in AML and ALL. Stratified analysis by dietary folate intake showed the increased risks of leukemia with the MTHFR 677TT and TS 2R3R/2R2R genotypes were only significant in individuals with low folate intake. A significant interaction between TS polymorphism and dietary folate intake was observed (P = 0.03). This study suggests that dietary folate intake and gender may modify the associations between MTHFR/TS polymorphisms and adult leukemia risk.

  7. Thermolabile Methylenetetrahydrofolate Reductase C677T Polymorphism and Homocysteine Are Risk Factors for Coronary Artery Disease in Moroccan Population

    PubMed Central

    Bennouar, Nawal; Allami, Abdellatif; Azeddoug, Houssine; Bendris, Abdenbi; Laraqui, Abdelilah; El Jaffali, Amal; El Kadiri, Nizar; Benzidia, Rachid; Benomar, Anwar; Fellat, Seddik; Benomar, Mohamed

    2007-01-01

    Increased plasma total homocysteine (tHcy) levels have been shown to be a risk factor for coronary artery disease (CAD). The common methylenetetrahydrofolate reductase C677T (MTHFR C677T) polymorphism has been reported to be a strong predictor of mild hyperhomocysteinaemia (HHcy). We assessed whether this mutation was associated with increased risk of CAD and plasma levels of tHcy. We also evaluated interactions between this polymorphism, mild elevated tHcy levels and conventional risk factors of CAD. Method. Using PCR-RFLP analysis, we studied the frequency of the C677T genotypes and its effect on CAD and on tHcy concentrations in 400 subjects without and with CAD angiographically confirmed. There were 210 subjects with CAD and 190 subjects without CAD. Results. The frequencies of the C677T genotypes were 53% (59.5% in controls versus 48.1% in cases), 34.8% (32.1 in controls versus 37.1 in cases), and 11.8% (8.4% in controls versus 14.8% in cases), respectively, for 677CC, 677CT, and 677TT. The genotype frequencies were significantly different between case and control groups (P < .05). The 677T allele enhances the risk of CAD associated to HHcy (P < .01). In multivariate analysis models, MTHFR C677T polymorphism effect on CAD was masked by other risk factors. HHcy was only and independently influenced by MTHFR polymorphism and smoking habits, and it is a strong predictor of CAD independently of conventional risk factors. Conclusion. Our data suggest that HHcy is strongly and independently associated to CAD risk increase; and MTHFR C677T polymorphism and smoking habits were the main predictors of tHcy levels. The CAD risk increase is mainly associated with mild HHcy in 677TT, whereas in 677CT and 677CC it is mainly associated with the conventional risk factors. PMID:17497026

  8. Methylenetetrahydrofolate reductase C677T and methionine synthase A2756G polymorphisms influence on leukocyte genomic DNA methylation level.

    PubMed

    Weiner, Alexandra S; Boyarskikh, Uljana A; Voronina, Elena N; Mishukova, Olga V; Filipenko, Maxim L

    2014-01-01

    Methionine synthase (MTR) and methylenetetrahydrofolate reductase (MTHFR) enzymes are involved in the metabolism of methyl groups, and thus have an important role in the maintenance of proper DNA methylation level. In our study we aimed to evaluate the effect of the polymorphism A2756G (rs1805087) in the MTR gene on the level of human leukocyte genomic DNA methylation. Since the well-studied polymorphism C677T (rs1801133) in the MTHFR gene has already been shown to affect DNA methylation, we aimed to analyze the effect of MTR A2756G independently of the MTHFR C677T polymorphism. For this purpose, we collected the groups of 80 subjects with the MTR 2756AA genotype and 80 subjects with the MTR 2756GG genotype, having equal numbers of individuals with the MTHFR 677CC and the MTHFR 677TT genotypes, and determined the level of DNA methylation in each group. Individuals homozygous for the mutant MTR 2756G allele showed higher DNA methylation level than those harboring the MTR 2756AA genotype (5.061 ± 1.761% vs. 4.501 ± 1.621%, P=0.0391). Individuals with wild-type MTHFR 677СC genotype displayed higher DNA methylation level than the subjects with mutant MTHFR 677TT genotype (5.103 ± 1.767% vs. 4.323 ± 1.525%, P=0.0034). Our data provide evidence that the MTR A2756G polymorphism increases the level of DNA methylation and confirm the previous reports that the MTHFR C677T polymorphism is associated with DNA hypomethylation. © 2013 Elsevier B.V. All rights reserved.

  9. Association of C677T polymorphism in the methylenetetrahydrofolate reductase gene (MTHFR gene) with ischemic stroke: a meta-analysis.

    PubMed

    Kumar, Amit; Kumar, Pradeep; Prasad, Manya; Sagar, Ram; Yadav, Arun Kumar; Pandit, Awadh Kishor; Jali, Vidishaa Prasad; Pathak, Abhishek

    2015-07-01

    Studies on association between methylenetetrahydrofolate reductase gene (MTHFR) C677T gene polymorphism and ischemic stroke have shown conflicting results. We have conducted a meta-analysis to determine the precise association of the C677T polymorphism of MTHFR gene with risk of ischemic stroke. We searched electronic databases Medline, EMBASE, and Google Scholar (last search dated till August 2014). Pooled odds ratios (ORs) with 95% confidence intervals (CIs) from random or fixed-effects models were calculated. The methodological quality of included studies was determined by the quality assessment scale. Thirty eight case-control studies fulfilled our inclusion criteria comprising 6310 patients and 8297 controls. The significant associations between MTHFR C677T genetic polymorphism and risk of ischemic stroke were observed in dominant (OR, 1·09; 95% CI, 1·06-1·12, P-value < 0·001) and recessive (OR, 1·31; 95% CI, 1·19-1·44, P-value < 0·001) inheritance models. In an Asian population, significant association between the MTHFR polymorphism and ischemic stroke was observed (dominant model: OR 1·36, 95% CI 1·23-1·49 and under recessive model OR, 1·29; 95% CI, 1·15-1·45). In the Caucasian population borderline, non-significant association was observed under dominant model of inheritance (OR, 1·05; 95% CI, 0·99-1·10) but significant association was observed under the recessive model of inheritance (OR, 1·33; 95% CI, 1·13-1·58). The present study results suggest that MTHFR C677T genetic polymorphism is a probable risk of ischemic stroke.

  10. Maternal Methylenetetrahydrofolate Reductase C677T Polymorphism and Down Syndrome Risk: A Meta-Analysis from 34 Studies

    PubMed Central

    Rai, Vandana; Yadav, Upendra; Kumar, Pradeep; Yadav, Sushil Kumar; Mishra, Om Prakesh

    2014-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme of folate metabolic pathway which catalyzes the irreversible conversion of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. 5-methyltetrahydrofolate donates methyl group for the methylation of homocysteine to methionine. Several studies have investigated maternal MTHFR C677T polymorphism as a risk factor for DS, but the results were controversial and inconclusive. To come into a conclusive estimate, authors performed a meta-analysis. Aim A meta-analysis of published case control studies was performed to investigate the association between maternal MTHFR C677T polymorphism and Down syndrome. Methods PubMed, Google Scholar, Elsevier, Springer Link databases were searched to select the eligible case control studies using appropriate keywords. The pooled odds ratio (OR) with 95%confidence interval were calculated for risk assessment. Results Thirty four studies with 3,098 DS case mothers and 4,852 control mothers were included in the present meta-analysis. The pooled OR was estimated under five genetic models and significant association was found between maternal MTHFR 677C>T polymorphism and Down syndrome under four genetic models except recessive model (for T vs. C, OR = 1.26, 95% CI = 1.09–1.46, p = 0.001; for TT vs. CC, OR = 1.49, 95% CI = 1.13–1.97, p = 0.008; for CT vs. CC, OR = 1.29, 95% CI = 1.10–1.51, p = 0.001; for TT+CT vs. CC, OR = 1.35, 95% CI = 1.13–1.60, p = 0.0008; for TT vs. CT+CC, OR = 0.76, 95% CI = 0.60–0.94, p = 0.01). Conclusion The results of the present meta-analysis support that maternal MTHFR C677T polymorphism is a risk factor for DS- affected pregnancy. PMID:25265565

  11. Methylenetetrahydrofolate reductase gene polymorphisms are associated with ischemic and hemorrhagic stroke: Dual effect of MTHFR polymorphisms C677T and A1298C.

    PubMed

    Sazci, Ali; Ergul, Emel; Tuncer, Nese; Akpinar, Gurler; Kara, Ihsan

    2006-12-11

    Hyperhomocysteinemia is an independent risk factor for ischemic stroke. The enzyme methylenetetrahydrofolate reductase (MTHFR) plays a critical role in modulating the levels of plasma homocysteine. Two polymorphisms in the MTHFR gene, C677T, A1298C result in reduced enzyme activity. The mechanisms of ischemic and hemorrhagic stroke are not well understood. Although controversial, previous studies have shown evidence of causality of both stroke subtypes in patients with methylenetetrahydrofolate reductase gene polymorphisms. Therefore, we examined whether the C677T and A1298C polymorphisms of MTHFR gene are genetic risk factors for both ischemic and hemorrhagic stroke in a Turkish Caucasian population. In a case-control study, 120 total unrelated stroke patients (92 ischemic stroke, 28 hemorrhagic stroke), and 259 healthy controls were genotyped for C677T and A1298C polymorphisms of the MTHFR gene using a PCR-RFLP based-method. The MTHFR 1298C allele (chi(2)=8.589; P=0.014), C1298C genotype (OR=2.544; P=0.004), and C677C/C1298C compound genotype (OR=3.020; P=0.001) were associated with overall stroke. The MTHFR 1298C allele (chi(2)=11.166; P=0.004), C1298C genotype (OR=2.950; P=0.001), and C677C/C1298C compound genotype (OR=3.463, P=0.0001) were strongly associated with ischemic stroke. Interestingly however, the MTHFR 677T allele (chi(2)=6.033; P=0.049), T677T genotype (OR=3.120; P=0.014), and T677T/A1298A compound genotype (OR=4.211; P=0.002) were associated with hemorrhagic stroke. In conclusion, the C677T and A1298C polymorphisms of the MTHFR gene are genetic risk factors for hamorrhagic and ischemic stroke respectively, independent of other atherothrombotic risk factors.

  12. A Meta-Analysis of Association between Methylenetetrahydrofolate Reductase Gene (MTHFR) 677C/T Polymorphism and Diabetic Retinopathy

    PubMed Central

    Luo, Shasha; Wang, Furu; Shi, Chao; Wu, Zhifeng

    2016-01-01

    Aims: To shed light on the conflicting findings of the association between the methylenetetrahydrofolate reductase gene (MTHFR) 677C/T polymorphism and the risk of diabetic retinopathy (DR), a meta-analysis was conducted. Methods: A predefined search was performed on 1747 DR cases and 3146 controls from 18 published studies by searching electronic databases and reference lists of relevant articles. A random-effects or fixed-effects model was used to estimate the sizes of overall and stratification effects of the MTHFR 677C/T polymorphism on the risk of DR, as appropriate. Results: Risks were evaluated by odds ratios (OR) with 95% confidence intervals (95% CI). We found a significant association between the MTHFR 677C/T polymorphism and the risk of DR for each genetic model (recessive model: OR = 1.67; 95% CI: 1.19–2.40 and dominant model: OR = 1.71; 95% CI: 1.28–2.28; respectively). In stratified analysis; we further found that the Asian group with both types of diabetes mellitus (DM) showed a significant association with genetic models (recessive model: OR = 2.16; 95% CI: 1.75–2.60 and dominant model: OR = 1.98; 95% CI: 1.42–2.76; respectively). Conclusions: Our study suggested that the MTHFR 677C/T polymorphism may contribute to DR development, especially in Asian populations. Prospective and additional genome-wide association studies (GWAS) are needed to clarify the real role of the MTHFR gene in determining susceptibility to DR. PMID:27517946

  13. Association between the methylenetetrahydrofolate reductase gene C677T polymorphism and sudden sensorineural hearing loss: a meta-analysis.

    PubMed

    Shu, Jingcheng; Yin, Shihua; Tan, An-Zhou; He, Meirong

    2015-09-01

    A variety of epidemiological studies have evaluated the association between methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism and sudden sensorineural hearing loss (SSNHL), but the results were inconsistent. The aim of this meta-analysis was to clarify more accurately the association of this polymorphism with SSNHL. A systematic literature search of the associated studies up to May 1, 2014, was conducted using the following electronic databases: PubMed, Embase, Medline, and the China National Knowledge Infrastructure. Statistical analyses were performed by STATA12.0 software, with odds ratios (ORs) and their 95 % confidence intervals (CIs). Six eligible studies including covering 1,271 objects were identified. A pooled analysis of these studies showed no significant association between C677T polymorphism and risk of SSNHL: T vs. C (OR = 1.334, POR = 0.105); TT vs. CC (OR = 1.580, POR = 0.231); CT vs. CC (OR = 1.500, POR = 0.123); TT vs. CC + CT (OR = 1.326, POR = 0.293); and TT + CT vs. CC (OR = 1.540, POR = 0.102). But in subgroup analysis, a significant association was found in European populations (T vs. C, OR = 1.542, 95 % CI 1.008-2.359, P = 0.046; TT vs. CT + CC, OR = 1.856, 95 % CI 1.245-2.767, P = 0.002). There was no significant association in any model in the Asian populations. The present meta-analysis suggests that MTHFR gene C677T polymorphism is significantly associated with increased risk of SSNHL disease in European populations, but no statistically significant association was found between the MTHFR C677T gene mutation and SSNHL in Asian. Further large and well-designed studies are needed to confirm this association.

  14. Polymorphisms in the methylenetetrahydrofolate reductase gene (MTHFR) are associated with susceptibility to adult acute myeloid leukemia in a Chinese population.

    PubMed

    Huang, Lulu; Deng, Donghong; Peng, Zhigang; Ye, Fanghui; Xiao, Qiang; Zhang, Bing; Ye, Bingbing; Mo, Zengnan; Yang, Xiaobo; Liu, Zhenfang

    2015-06-01

    Methylenetetrahydrofolate reductase (MTHFR) is an essential enzyme in the metabolism of folate. Since acute myeloid leukemia (AML) is characterized by rapidly proliferating tissues that have a high requirement for DNA synthesis, it is possible that the presence of MTHFR polymorphisms could be linked to the multifactorial process of AML development. We evaluated the role of MTHFR C677T and A1298C polymorphisms in a case-control study comprising 98 AML patients and 2016 healthy controls in a Southern Chinese population. We further conducted a sub-study restricted to individuals who neither smoked nor drank alcohol (70 AML patients and 160 healthy controls). MTHFR polymorphisms in the patient and control groups were evaluated by SNaP shot genotype techniques and Illumina BeadChip, respectively. Logistic regression was used to assess the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs). The MTHFR 1298AC genotype and the 677CC/1298AC haplotype were significantly associated with a decreased risk of AML compared with the AA genotype and 677CC/1298AA haplotype (OR=0.60, 95% CI: 0.38-0.95, P=0.03; OR=0.49, 95% CI: 0.27-0.90, P=0.02, respectively). In addition, the 677TT genotype was significantly associated with an increased risk of AML compared with the AA genotype only in non-smokers and non-drinkers (OR=4.78; 95% CI=1.38-16.61, P=0.01). The results might suggest that MTHFR polymorphisms are significantly associated with AML risk. In addition, the role of MTHFR genetic susceptibility could be greater among non-smokers and non-drinkers. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. The methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and tumor risk: evidence from 134 case-control studies.

    PubMed

    Tang, Min; Wang, Shang-Qian; Liu, Bian-Jiang; Cao, Qiang; Li, Bing-Jie; Li, Peng-Chao; Li, Yong-Fei; Qin, Chao; Zhang, Wei

    2014-07-01

    Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism, which is essential for DNA synthesis and methylation. Genetic variations in the MTHFR gene seem to contribute to a decreased activity of MTHFR, ultimately confer increased susceptibility to cancer. As the most extensively studied polymorphism, MTHFR C677T polymorphism was shown to contribute to cancer susceptibility but the results were inconsistent. The authors performed a meta-analysis including 134 studies (46,207 cases and 69,160 controls) to address the issue. Odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to assess the association. Overall, a significant elevated risk of cancer was associated with the MTHFR C677T polymorphism in T-allele versus C-allele comparison (OR = 1.06, 95% CI 1.02-1.11, P(heterogeneity) < 0.001), homozygote model (OR = 1.08, 95% CI 1.01-1.17, P(heterogeneity) < 0.001) and dominant model (OR = 1.05, 95% CI 1.00-1.10, P(heterogeneity) < 0.001). In the stratified analyses, significantly increased cancer risks were indicated among Asians in all genetic models except for heterozygote model. Further analysis revealed that C677T was significantly associated with an increased risk of esophageal and stomach cancer. This meta-analysis supports an association between the MTHFR C677T polymorphism and increased risk of esophageal and stomach cancer, especially among Asians. Additionally, more high-quality studies and that the covariates responsible for heterogeneity should be controlled to obtain a more conclusive response about the function of MTHFR C677T in cancer.

  16. Is the C677T polymorphism in methylenetetrahydrofolate reductase gene or plasma homocysteine a risk factor for diabetic peripheral neuropathy in Chinese individuals?☆

    PubMed Central

    Wang, Hongli; Fan, Dongsheng; Hong, Tianpei

    2012-01-01

    The present study enrolled 251 diabetic patients, including 101 with neuropathy and 150 without neuropathy. Of the 150 patients, 100 had no complications, such as retinopathy, nephropathy, or neuropathy. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to identify methylenetetrahydrofolate reductase gene variants. Plasma homocysteine levels were also measured. Homocysteine levels and the frequency of hyperhomocysteinemia were significantly higher in patients with diabetic peripheral neuropathy compared with diabetic patients without neuropathy (P < 0.05). In logistic regression analysis with neuropathy as the dependent variable, the frequency of C677T in methylenetetrahydrofolate reductase was significantly higher in patients with diabetic peripheral neuropathy compared with patients without diabetic complications. Homocysteine levels were significantly higher in patients with diabetic peripheral neuropathy carrying the 677T allele and low folic acid levels. In conclusion, hyperhomocysteinemia is an independent risk factor for diabetic neuropathy in Chinese patients with diabetes. The C677T polymorphism in methylenetetrahydrofolate reductase and low folic acid levels may be risk factors for diabetic peripheral neuropathy in Chinese patients with diabetes. PMID:25538764

  17. Is the C677T polymorphism in methylenetetrahydrofolate reductase gene or plasma homocysteine a risk factor for diabetic peripheral neuropathy in Chinese individuals?

    PubMed

    Wang, Hongli; Fan, Dongsheng; Hong, Tianpei

    2012-10-25

    The present study enrolled 251 diabetic patients, including 101 with neuropathy and 150 without neuropathy. Of the 150 patients, 100 had no complications, such as retinopathy, nephropathy, or neuropathy. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to identify methylenetetrahydrofolate reductase gene variants. Plasma homocysteine levels were also measured. Homocysteine levels and the frequency of hyperhomocysteinemia were significantly higher in patients with diabetic peripheral neuropathy compared with diabetic patients without neuropathy (P < 0.05). In logistic regression analysis with neuropathy as the dependent variable, the frequency of C677T in methylenetetrahydrofolate reductase was significantly higher in patients with diabetic peripheral neuropathy compared with patients without diabetic complications. Homocysteine levels were significantly higher in patients with diabetic peripheral neuropathy carrying the 677T allele and low folic acid levels. In conclusion, hyperhomocysteinemia is an independent risk factor for diabetic neuropathy in Chinese patients with diabetes. The C677T polymorphism in methylenetetrahydrofolate reductase and low folic acid levels may be risk factors for diabetic peripheral neuropathy in Chinese patients with diabetes.

  18. Methylenetetrahydrofolate Reductase (MTHFR) (C677T and A1298C) Polymorphisms and Vascular Complications in Patients with Type 2 Diabetes.

    PubMed

    Fekih-Mrissa, Najiba; Mrad, Meriem; Ibrahim, Hazard; Akremi, Imen; Sayeh, Aicha; Jaidane, Amel; Ouertani, Haroun; Zidi, Borni; Gritli, Nasreddine

    2017-08-01

    To assess whether 2 polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) gene, C677T and A1298C, are risk factors for vascular complications in Tunisian patients with type 2 diabetes mellitus. The MTHFR polymorphisms were genotyped, and plasma homocysteine levels were evaluated in 160 Tunisian patients with type 2 diabetes mellitus. Prevalence of the 2 heterozygous polymorphisms of the thermolabile MTHFR gene (CT and AC) was encountered more commonly in patients with diabetes mellitus than in the healthy controls (p<10(-3)). Subjects with diabetes had significantly higher homocysteine (Hcy) levels than the control subjects; however, there was no statistical difference in plasma Hcy values between carriers of mutant genotypes (CT/TT for C677T and AC/CC for A1298C) and wild types (CC and AA) in patients with diabetes. Retinopathy was found to be a vascular complication in patients with either the 677CT or the 1298(AC+CC) genotype more commonly than in those with the wild-type genotypes (p=0.003; OR=3.2, 95% CI, 1.4 to 7.4; p<10(-3); OR=5.9, 95% CI, 2.7 to 13). Only patients who carry the A1298C mutation (AC+CC) are at risk for at least 1 complication (p=0.002). Double heterozygous mutants were at the greatest risk for retinopathy and for suffering at least 1 complication (p<10(-3)). Studies involving a larger study population and various ethnic groups are required before ruling out the role of MTHFR gene in type 2 diabetes mellitus and in vascular complications. Copyright © 2017 Diabetes Canada. Published by Elsevier Inc. All rights reserved.

  19. Methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism and diabetic nephropathy susceptibility in patients with type 2 diabetes mellitus.

    PubMed

    Zhou, Tian-Biao; Drummen, Gregor P C; Jiang, Zong-Pei; Li, Hong-Yan

    2015-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme that regulates nucleotide synthesis and DNA methylation. The MTHFR C677T gene polymorphism (rs1801133), a C → T transition at nucleotide 677 in exon 4, is a common gene variant of MTHFR and has been implicated in diabetic nephropathy, albeit with inconsistent results. Here, we performed a meta-analysis to assess the common effect size of this polymorphism on DN susceptibility. Case-control studies on the association of the MTHFR C677T gene polymorphism with DN risk were retrieved from databases up to August 1, 2013, and eligible studies were recruited into the meta-analysis and further analyzed. Of 132 studies, 33 were identified as suitable for this analysis. The results showed that T allele and TT genotype were distinctly associated with DN susceptibility in the overall population and Asians, and might be a risk factor in Caucasians and Africans (T allele: Overall population: p < 0.00001, Asians: p = 0.0002, Caucasians: p = 0.02, Africans: p < 0.00001; TT genotype: Overall population: p < 0.00001, Asians: p = 0.0003, Caucasians: p = 0.008, Africans: p = 0.0003). Furthermore, the analysis suggested that the CC genotype might play a protective role against DN onset in patients with type 2 diabetes for the overall population, Asians, Caucasian and Africans. However, due to the limited sample size in the African population, these results should be interpreted with care. In conclusion, the MTHFR C677T T allele or TT genotype might be a significant genetic molecular marker to determine the risk of DN in patients with type 2 diabetes and help to develop suitable disease prevention and management strategies.

  20. Association between a microRNA-214 binding site polymorphism in the methylenetetrahydrofolate reductase gene and esophageal squamous cell carcinoma.

    PubMed

    Shen, G R; Li, W Z; Liu, Y C; Li, X P; Yuan, H Y

    2016-05-13

    MicroRNAs (miRNAs) are key regulators of gene expression and play an important role in the development and progression of various diseases including esophageal squamous cell carcinoma (ESCC). In this study, we determined whether a polymorphism at the miR-214 binding site in the 3'-untranslated region (3'-UTR) of the methylenetetrahydrofolate reductase gene (MTHFR) is associated with susceptibility to ESCC. A total of 448 ESCC cases and 460 gender- and age-matched subjects were recruited for the study. The genotypes of the rs114673809 single nucleotide polymorphism (SNP) were determined by polymerase chain reaction sequencing. Associations between genotypes of MTHFR rs114673809 and ESCC risk were determined using logistic regression analyses. In the recessive model, when the MTHFR rs114673809 GG homozygote genotype was used as the reference group, the GA genotype was not associated with the risk of ESCC (GA vs GG: OR = 1.261, 95%CI = 0.960-1.657, P = 0.110), but the AA genotype was associated with increased risk of ECSS (AA vs GG: OR = 1.752, 95%CI = 1.076-2.853, P = 0.027). Additionally, the rs114673809 A allele carriers also showed a 1.286-fold increased ESCC risk compared with those carrying the rs114673809 G allele genotype. Furthermore, we observed a significant increase in plasma homocysteine levels in ESCC cases carrying the AA genotype relative to ESCC cases carrying the GG genotype. Our data demonstrate that a polymorphism at the miR-214 binding site in the 3'-UTR of MTHFR is an ESCC susceptibility SNP in the Chinese population.

  1. Methylenetetrahydrofolate reductase C677T polymorphism is associated with increased risk of coronary artery disease in young South African Indians.

    PubMed

    Ramkaran, Prithiksha; Phulukdaree, Alisa; Khan, Sajidah; Moodley, Devapregasan; Chuturgoon, Anil A

    2015-10-15

    Methylenetetrahydrofolate reductase (MTHFR) reduces 5',10'-methylenetetrahydrofolate to 5'-methyltetrahydrofolate, and is involved in remethylation of homocysteine to methionine, two important reactions involved in folate metabolism and methylation pathways. The common MTHFR C677T single nucleotide polymorphism (SNP) (rs1801133) has been associated with raised levels of homocysteine, a well known risk factor for coronary artery disease (CAD). CAD is a major cause of mortality worldwide. The age of onset of this chronic disorder is on the decline, particularly in the Indian population. Indians in South Africa (SA) have a higher prevalence of premature CAD compared to Black South Africans. The MTHFR C677T SNP has not been investigated in the SA Indian population. The present study therefore investigated the MTHFR C677T SNP in young SA Indian males with CAD compared to young Indian and Black male controls. A total of 290 subjects were recruited into this study which included 106 CAD patients (diagnosed on angiography, mean age 37.5, range 24-45 years), 100 Indian male controls (mean age 37.5, range 28-45 years), and 84 Black male controls (mean age 36.4, range 25-45). Polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) was used to genotype CAD patients and healthy controls. Data for clinical markers were obtained from pathology reports. There was a significant association between the 677 MTHFR variant (T) allele and CAD patients compared to the healthy Indian controls (p=0.0353, OR=2.105 95% CI 1.077-4.114). Indian controls presented with a higher frequency of the variant allele compared to Black controls (7% vs. 2% respectively, p=0.0515 OR=3.086 95% CI 0.9958-9.564). The MTHFR C677T SNP did not influence levels of total cholesterol, LDL, HDL, triglycerides, fasting glucose, fasting insulin, HbA1c or hsCRP. The higher frequency of the MTHFR 677 variant allele in South African Indians may be a contributing factor to the higher

  2. Polymorphisms in methylenetetrahydrofolate reductase gene and risk of non-Hodgkin lymphoma in a multi-ethnic population.

    PubMed

    Suthandiram, Sujatha; Gan, Gin Gin; Zain, Shamsul Mohd; Haerian, Batoul Sadat; Bee, Ping Chong; Lian, Lay Hoong; Chang, Kian Meng; Ong, Tee Chuan; Mohamed, Zahurin

    2014-05-01

    An imbalance in folate metabolism can adversely affect DNA synthesis and methylation systems which can lead to susceptibility to non-Hodgkin lymphoma (NHL). Whether single nucleotide polymorphisms (SNPs) and their haplotypes in the methylenetetrahydrofolate reductase (MTHFR) are associated with NHL, remain inconclusive. We investigated the association between MTHFR C677T and A1298C SNPs and NHL risk in a population which is made up of Malay, Chinese and Indian ethnic subgroups. A total of 372 NHL patients and 722 controls were genotyped using the Sequenom MassARRAY platform. Our results of the pooled subjects failed to demonstrate significant association between the MTHFR C677T and A1298C SNPs with NHL and its subtypes. The results were in agreement with the previous meta-analyses. In the Indian ethnic subgroup however, single locus analysis of MTHFR A1298C appears to confer risk to NHL (Odds ratio (OR) 1.91, 95% confidence interval (95% CI) 1.22-3.00, P=0.006). The risk is almost doubled in homozygous carrier of MTHFR 1298CC (OR 4.03, 95% CI 1.56-10.43, P=0.004). Haplotype analysis revealed higher frequency of CC in the Indian NHL patients compared with controls (OR 1.86, 95% CI 1.18-2.93, P=0.007). There is lack of evidence to suggest an association between MTHFR C677T and A1298C with the risk of NHL in the Malays and Chinese. In the Indians however, the MTHFR A1298C confers risk to NHL. This study suggests ethnicity modifies the relationship between polymorphisms in the folate-metabolizing gene and NHL.

  3. Role of 677C→T polymorphism a single substitution in methylenetetrahydrofolate reductase (MTHFR) gene in North Indian infertile men.

    PubMed

    Naqvi, Hena; Hussain, Syed Rizwan; Ahmad, Mohammad Kaleem; Mahdi, Farzana; Jaiswar, Shyam Pyari; Shankhwar, Satya Narayain; Mahdi, Abbas Ali

    2014-02-01

    Failure or severe difficulty in conceiving a child is surprisingly common, worldwide problem. Half of these cases are due to male factors with defects in sperm (1 in 15 men) being the single most common cause. Also about 60-75 % of male infertility cases are idiopathic, since the molecular mechanisms underlying the defects remain unknown. DNA methylation is crucial for spermatogenesis and high methylenetetrahydrofolate reductase (MTHFR) activity in adult testis than other organs in mouse, signifies its critical role in spermatogenesis. According to recent findings there is a correlation of epigenetic regulation of several imprinted genes with disturbed spermatogenesis and fertility. Consequently any change in the MTHFR gene sequence can modify the spermatogenesis including transmission of infertility to the carriers. The aim of the study is to analyze the distribution of the single nucleotide polymorphism C677T in the MTHFR gene in 637 North Indian infertile patients and 364 fertile North Indian men as controls by using PCR-RFLP technique and Chi Square test for statistical analysis. The average MTHFR 677CC, 677CT, 677TT genotype frequencies of total infertile men were 70.17, 24.17, 5.65 % in infertile men and 75.27, 21.7, 2.74 % in controls, respectively. The average frequency of the MTHFR 677T allele was 17.73 % in infertile men as compared to 13.59 % in controls. The statistical difference was significant. Disease risk was found 2.27-folds increased in patients who were carrying T allele. We found an association of C677T polymorphism with male infertility and that it may be a genetic risk factor for male infertility in North Indian population.

  4. Folate intake, serum folate, serum total homocysteine levels and methylenetetrahydrofolate reductase C677T polymorphism in young Japanese women.

    PubMed

    Hiraoka, Mami

    2004-08-01

    Various factors influence folate status and requirements. To investigate the folate status in young Japanese women (n=340, 20-22 y), I determined the serum folate and total homocysteine (tHcy), and examined the influence of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on folate status in a subgroup of 252 of the women. I calculated folate consumption based on records of food intake weighed over 3 d using the standard Tables of Food Composition in Japan (5th revised edition) and the US Food Composition Table based on the USDA nutrient database excluding fortification. Serum folate and total homocysteine (tHcy) levels were determined by chemiluminescent-competitive protein binding assay and HPLC, respectively. The mean intake of folate was 323+/-133 and 196+/-71 microg/d, and 86.5% and 42.1% of the participants consumed more than the RDA of 200 microg of folate, according to the Japanese and US tables, respectively. The main sources of dietary folate were vegetables, green tea and bread. Serum folate levels were significantly correlated with folate intake (r=0.249, p<0.001). Serum tHcy levels were above 15 micromol/L in four participants. I found significant negative correlations between serum tHcy and folate intake (r=-0.175, p<0.05), and between serum tHcy and serum folate (r=-0.297, p<0.0001). The frequencies of the CC, CT and TT genotypes of the MTHFR gene were 32.9, 51.6 and 15.5%, respectively. Among individuals with the TT genotype, serum folate and tHcy levels were lower and higher, respectively, than in those with the other genotypes, regardless of folate intake above RDA. These data suggest that the current RDA of folate estimated based on foreign data might not be sufficient for Japanese and that this value might require reassessment.

  5. Associations between asymmetric dimethylarginine, homocysteine, and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism (rs1801133) in rheumatoid arthritis.

    PubMed

    Dimitroulas, T; Sandoo, A; Hodson, J; Smith, J; Douglas, K M; Kitas, G D

    2016-07-01

    The aim of our study was to determine whether asymmetric dimethylarginine (ADMA) levels are associated with homocysteine (Hcy) and methylenetetrahydrofolate reductase (MTHFR) C677T (rs1801133) gene variants in patients with rheumatoid arthritis (RA). Serum ADMA and Hcy levels were measured in 201 RA individuals [155 (77.1%) females, median age 67 years (interquartile range 59-73)]. The MTHFR C677T polymorphism was assessed by using the LightCyclerTM System. Initially, ADMA was compared across the categories of MTHFR using a one-way analysis of variance (ANOVA), followed by a multivariate model, which accounted for Hcy, age, erythrocyte sedimentation rate (ESR), and homeostatic model assessment (HOMA). In univariable analysis, ADMA differed significantly across the categories of MTHFR (p = 0.037). Patients with the MTHFR 677TT genotype had the highest ADMA levels, with a mean of 0.62 (SE = 0.03), significantly higher than either those patients carrying the MTHFR 677CT (0.55, SE = 0.01) or the MTHFR 677CC (0.55, SE = 0.01) genotype (p = 0.042) in both cases. In the multivariable model, Hcy (p = 0.022) and ESR (p < 0.001) were found to have significant positive associations with ADMA but the relationship between MTHFR gene variants and ADMA was found to be non-significant (p = 0.102). Hcy and ADMA are significantly associated in RA. It is plausible that abnormal Hcy metabolism plays an important role in premature atherosclerosis in RA by promoting ADMA accumulation and leading to the derangement of vascular haemostasis.

  6. Methylenetetrahydrofolate reductase: biochemical characterization and medical significance.

    PubMed

    Trimmer, Elizabeth E

    2013-01-01

    Methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of 5,10-methylenetetrahydofolate (CH2-H4folate) to 5-methyltetrahydrofolate (CH3-H4folate). The enzyme employs a noncovalently-bound flavin adenine dinucleotide (FAD), which accepts reducing equivalents from NAD(P)H and transfers them to CH2-H4folate. The reaction provides the sole source of CH3-H4folate, which is utilized by methionine synthase in the synthesis of methionine from homocysteine. MTHFR plays a key role in folate metabolism and in the homeostasis of homocysteine; mutations in the enzyme lead to hyperhomocyst(e)inemia. A common C677T polymorphism in MTHFR has been associated with an increased risk for the development of cardiovascular disease, Alzheimer's disease, and depression in adults, and of neural tube defects in the fetus. The mutation also confers protection for certain types of cancers. This review presents the current knowledge of the enzyme, its biochemical characterization, and medical significance.

  7. Association between the methylenetetrahydrofolate reductase c.677C>T polymorphism and bone mineral density: an updated meta-analysis.

    PubMed

    Li, Hong-Zhuo; Wang, Wei; Liu, Yi-Ling; He, Xiao-Feng

    2016-02-01

    Many studies have reported an association between the methylenetetrahydrofolate reductase (MTHFR) c.677C>T polymorphism and reduced bone mineral density (BMD), but results have been inconsistent. We, therefore, performed a meta-analysis to further explore this association. Twenty-one studies, comprising 33,045 subjects, analyzed the association of MTHFR c.677C>T with femoral neck BMD. Significant association with reduced BMD was observed in Caucasians (recessive model: WMD = -0.004 g/cm(2), 95 % CI -0.008 to -0.006), post-menopausal women (recessive model: WMD = -0.005 g/cm(2), 95 % CI -0.007 to -0.003), men (dominant model: WMD = -0.004 g/cm(2), 95 % CI -0.005 to -0.004; recessive model: WMD = -0.004 g/cm(2), 95 % CI -0.005 to -0.004; TT vs. CC: WMD = -0.006 g/cm(2), 95 % CI -0.006 to -0.006; CT vs. CC: WMD = -0.003 g/cm(2), 95 % CI -0.003 to -0.003), and cohort studies (recessive model: WMD = -0.003 g/cm(2), 95 % CI -0.006 to -0.001). Twenty-two studies, which included 32,271 subjects, analyzed the MTHFR c.677C>T association with lumbar spine BMD. Significant association with reduced BMD was observed in Caucasians, women, post-menopausal women, men, and cohort studies. Seven studies, comprising 6806 subjects, analyzed the MTHFR c.677C>T association with total hip BMD, but no significant association was observed in any population. Nine studies involving 5591 subjects analyzed the association with total body BMD. Significant association with reduced BMD was observed in overall and women subgroup analyses. In summary, this meta-analysis indicates that the MTHFR c.677C>T polymorphism is associated with reduced BMD in lumbar spine and femoral neck in Caucasians, post-menopausal women, and men, and with total body BMD in women. In addition, our results suggest that new studies examining the association between MTHFR c.677C>T polymorphism and BMD of lumbar spine and femoral neck in Asians is warranted, because I (2) > 75.0 % was observed.

  8. Associations between Methylenetetrahydrofolate Reductase (MTHFR) Polymorphisms and Non-Alcoholic Fatty Liver Disease (NAFLD) Risk: A Meta-Analysis

    PubMed Central

    Sun, Man-Yi; Zhang, Li; Shi, Song-Li; Lin, Jing-Na

    2016-01-01

    Background C677T and A1298C are the most common allelic variants of Methylenetetrahydrofolate Reductase (MTHFR) gene. The association between MTHFR polymorphisms and the occurrence of non-alcoholic fatty liver disease (NAFLD) remains controversial. This study was thus performed to examine whether MTHFR mutations are associated with the susceptibility to NAFLD. Methods A first meta-analysis on the association between the MTHFR polymorphisms and NAFLD risks was carried out via Review Manager 5.0 and Stata/SE 12.0 software. The on-line databases, such as PubMed, EMBASE, CENTRAL, WOS, Scopus and EBSCOhost (updated to April 1st, 2016), were searched for eligible case-control studies. The odd radio (OR), 95% confidence interval (CI) and P value were calculated through Mantel-Haenszel statistics under random- or fixed-effect model. Results Eight articles (785 cases and 1188 controls) contributed data to the current meta-analysis. For C677T, increased NAFLD risks were observed in case group under homozygote model (T/T vs C/C, OR = 1.49, 95% CI = 1.03~2.15, P = 0.04) and recessive model (T/T vs C/C+C/T, OR = 1.42, 95% CI = 1.07~1.88, P = 0.02), but not the other genetics models, compared with control group. For A1298C, significantly increased NAFLD risks were detected in allele model (C vs A, OR = 1.53, 95% CI = 1.13~2.07, P = 0.006), homozygote model (C/C vs A/A, OR = 2.81, 95% CI = 1.63~4.85, P = 0.0002), dominant model (A/C+C/C vs A/A, OR = 1.60, 95% CI = 1.06~2.41, P = 0.03) and recessive model (C/C vs A/A+A/C, OR = 2.08, 95% CI = 1.45~3.00, P<0.0001), but not heterozygote model. Conclusion T/T genotype of MTHFR C677T polymorphism and C/C genotype of MTHFR A1298C are more likely to be associated with the susceptibility to NAFLD. PMID:27128842

  9. Associations between Methylenetetrahydrofolate Reductase (MTHFR) Polymorphisms and Non-Alcoholic Fatty Liver Disease (NAFLD) Risk: A Meta-Analysis.

    PubMed

    Sun, Man-Yi; Zhang, Li; Shi, Song-Li; Lin, Jing-Na

    2016-01-01

    C677T and A1298C are the most common allelic variants of Methylenetetrahydrofolate Reductase (MTHFR) gene. The association between MTHFR polymorphisms and the occurrence of non-alcoholic fatty liver disease (NAFLD) remains controversial. This study was thus performed to examine whether MTHFR mutations are associated with the susceptibility to NAFLD. A first meta-analysis on the association between the MTHFR polymorphisms and NAFLD risks was carried out via Review Manager 5.0 and Stata/SE 12.0 software. The on-line databases, such as PubMed, EMBASE, CENTRAL, WOS, Scopus and EBSCOhost (updated to April 1st, 2016), were searched for eligible case-control studies. The odd radio (OR), 95% confidence interval (CI) and P value were calculated through Mantel-Haenszel statistics under random- or fixed-effect model. Eight articles (785 cases and 1188 controls) contributed data to the current meta-analysis. For C677T, increased NAFLD risks were observed in case group under homozygote model (T/T vs C/C, OR = 1.49, 95% CI = 1.03~2.15, P = 0.04) and recessive model (T/T vs C/C+C/T, OR = 1.42, 95% CI = 1.07~1.88, P = 0.02), but not the other genetics models, compared with control group. For A1298C, significantly increased NAFLD risks were detected in allele model (C vs A, OR = 1.53, 95% CI = 1.13~2.07, P = 0.006), homozygote model (C/C vs A/A, OR = 2.81, 95% CI = 1.63~4.85, P = 0.0002), dominant model (A/C+C/C vs A/A, OR = 1.60, 95% CI = 1.06~2.41, P = 0.03) and recessive model (C/C vs A/A+A/C, OR = 2.08, 95% CI = 1.45~3.00, P<0.0001), but not heterozygote model. T/T genotype of MTHFR C677T polymorphism and C/C genotype of MTHFR A1298C are more likely to be associated with the susceptibility to NAFLD.

  10. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and age at onset of schizophrenia: no consistent evidence for an association in the Nordic population.

    PubMed

    Saetre, Peter; Grove, Jakob; Børglum, Anders D; Mors, Ole; Werge, Thomas; Andreassen, Ole A; Vares, Maria; Agartz, Ingrid; Terenius, Lars; Jönsson, Erik G

    2012-12-01

    Methylenetetrahydrofolate reductase (MTHFR) is an enzyme involved in metabolic pathways of importance for nucleotide synthesis and methylation of DNA, membranes, proteins and lipids. The MTHFR gene includes a common polymorphism (rs1801133 or C677T), which is associated with enzyme activity. The T-allele of the C677T polymorphism has been associated with earlier age at onset of schizophrenia in a Scandinavian population, although no association was found in replication attempts in other populations. Extending the study to five Nordic samples consisting of 2,198 patients with schizophrenia, including the original Scandinavian samples, there was no significant association between MTHFR C677T polymorphism and age at onset in schizophrenia. The present results do not suggest that the investigated MTHFR polymorphism has any significant influence on age at onset of schizophrenia in the Nordic population. Copyright © 2012 Wiley Periodicals, Inc.

  11. Methylenetetrahydrofolate Reductase (MTHFR) C677T Polymorphism and Age at Onset of Schizophrenia: No Consistent Evidence for an Association in the Nordic Population

    PubMed Central

    Saetre, Peter; Grove, Jakob; Børglum, Anders D; Mors, Ole; Werge, Thomas; Andreassen, Ole A; Vares, Maria; Agartz, Ingrid; Terenius, Lars; Jönsson, Erik G

    2012-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is an enzyme involved in metabolic pathways of importance for nucleotide synthesis and methylation of DNA, membranes, proteins and lipids. The MTHFR gene includes a common polymorphism (rs1801133 or C677T), which is associated with enzyme activity. The T-allele of the C677T polymorphism has been associated with earlier age at onset of schizophrenia in a Scandinavian population, although no association was found in replication attempts in other populations. Extending the study to five Nordic samples consisting of 2,198 patients with schizophrenia, including the original Scandinavian samples, there was no significant association between MTHFR C677T polymorphism and age at onset in schizophrenia. The present results do not suggest that the investigated MTHFR polymorphism has any significant influence on age at onset of schizophrenia in the Nordic population. © 2012 Wiley Periodicals, Inc. PMID:23076983

  12. Methylenetetrahydrofolate reductase C677T polymorphism, hypertension and risk of stroke: a prospective, nested case-control study.

    PubMed

    Jiang, Shanqun; Li, Jianping; Zhang, Yan; Venners, Scott A; Tang, Genfu; Wang, Yu; Li, Zhiping; Xu, Xiping; Wang, Binyan; Huo, Yong

    2017-03-01

    Hyperhomocysteinemia is a risk factor for cardiovascular disease. To date, limited prospective studies have examined the joint effects of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, hyperhomocysteinemia and conventional vascular risk factors on risk of stroke and stroke death. A total of 39 165 subjects from nine communities within Anqing, Anhui Province, China were prospectively followed from March 1995 to April 2005, with an average follow-up period of 6.2 years. None of the subjects had any history of vascular events at baseline. At follow-up, 251 incident stroke cases were identified. Using a nested, case-control study design, this analysis includes 106 cases with complete MTHFR C677T genotyping data and plasma samples. We selected 106 controls without vascular events matched for age, sex, community and years of plasma storage. Plasma total homocysteine (tHcy) level was measured by high-performance liquid chromatography. Hypertension was independently associated with incident stroke and stroke death after adjusting for important covariates including plasma log-transformed Hcy level. Relative to non-carriers of the MTHFR 677TT genotype with no hypertension, the adjusted odds ratio (95% confidence interval) of stroke and stroke death among hypertensive carriers of the MTHFR 677TT genotype was 10.6 (3.2 to 34.8), 5.8 (1.6 to 21.3), respectively. After excluding subjects with plasma Hcy above 20 μmol/L, the relative odds for stroke, but not for stroke death, was more significantly pronounced (OR = 24.1, 95% CI: 2.3 to 246.1) among subjects with moderate plasma Hcy levels. However, there was no significant interactive effect between hypertensive status and the MTHFR C677T variant on the odds of the two outcomes as estimated by interaction models. Our major findings suggest that joint effects of the MTHFR C677T polymorphism and hypertension are consistent in predicting a significantly high risk of stroke. In addition for moderate plasma

  13. Serum homocysteine, vitamin B12, folic acid levels and methylenetetrahydrofolate reductase (MTHFR) gene polymorphism in vitiligo.

    PubMed

    Yasar, Ali; Gunduz, Kamer; Onur, Ece; Calkan, Mehmet

    2012-01-01

    The aim of this study was to determine serum vitamin B12, folic acid and homocysteine (Hcy) levels as well as MTHFR (C677, A1298C) gene polymorphisms in patients with vitiligo, and to compare the results with healthy controls. Forty patients with vitiligo and 40 age and sex matched healthy subjects were studied. Serum vitamin B12 and folate levels were determined by enzyme-linked immunosorbent assay. Plasma Hcy levels and MTHFR polymorphisms were determined by chemiluminescence and real time PCR methods, respectively. Mean serum vitamin B12 and Hcy levels were not significantly different while folic acid levels were significantly lower in the control group. There was no significant relationship between disease activity and vitamin B12, folic acid and homocystein levels. No significant difference in C677T gene polymorphism was detected. Heterozygote A1298C gene polymorphism in the patient group was statistically higher than the control group. There was no significant relationship between MTHFR gene polymorphisms and vitamin B12, folic acid and homocysteine levels. In conclusion, vitamin B12, folate and Hcy levels are not altered in vitiligo and MTHFR gene mutations (C677T and A1298C) do not seem to create susceptibility for vitiligo.

  14. Determination of Methylenetetrahydrofolate Reductase (MTHFR) gene polymorphism in Turkish patients with nonsyndromic cleft lip and palate.

    PubMed

    Aşlar, Deniz; Özdiler, Erhan; Altuğ, Ayşe Tuba; Taştan, Hakkı

    2013-07-01

    To investigate the association between MTHFR C677T polymorphism and Turkish patients with nonsyndromic cleft lip and/or palate (nsCL/P) and to determine the prevalence of the Turkish population. Molecular analysis of gene polymorphisms were carried out using polymerase chain reactions and restriction enzyme digestions. In our study, 80 patients with nsCL/P and 125 unrelated individuals from Turkey were studied. We found that MTHFR C677T polymorphism is a significant risk factor for nsCL/P in Turkey (p=0.0004). These results support the impact of MTHFR C677T polymorphism and importance of folic acid intake in the etiology of nsCL/P. MTHFR gene which is localized in the relevant region of chromosome 1p36.3 not been studied Turkish patients with nsCL/P and the prevalence of our country not to be determined. We revealed statistically association between the MTHFR C677T gene polymorphism and nonsyndromic cleft lip and/or palate in the Turkish population. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphism with ischemic stroke in the Eastern Chinese Han population.

    PubMed

    Lv, Q-Q; Lu, J; Sun, H; Zhang, J-S

    2015-04-27

    The association between the MTHFR genetic polymorphism and ischemic stroke has been reported by a number of investigators. However, the results have been controversial and conflicting. The aim of this study was to explore the association between the MTHFR variants C677T and A1298C and the risk of ischemic stroke in an Eastern Chinese Han population. A total of 199 patients with ischemic stroke and 241 controls were recruited. Genotyping of the MTHFR C677T and A1298C polymorphisms was carried out using the Taqman 7900HT Sequence Detection System. The overall estimates (odds ratio: OR) for the allele (C) and genotype (AC+CC) of the A1298C polymorphism were 1.57 [95% confidence interval (CI) = 1.16-2.10], and 2.36 (95%CI = 1.39-4.00), respectively, establishing significant association of the MTHFR A1298C polymorphism with ischemic stroke. In contrast, there were no statistically significant differences compared to controls between MTHFR C677T polymorphic variants in the association ischemic stroke risk. Furthermore, haplotype-based analysis demonstrated that compared with the C-677-A-1298 haplotype, the C-677-C-1298 and T-677-C-1298 haplotypes showed significant increased risk of ischemic stroke (OR = 1.56; 95%CI = 1.07- 2.2; P = 0.02; OR = 1.76; 95%CI = 1.17-2.65; P < 0.01, respectively). We concluded that the A1298C polymorphism and the haplotypes C-677-C-1298 and T-677-C-1298 in MTHFR might modulate the risk of ischemic stroke in the Eastern Chinese Han population.

  16. Methylenetetrahydrofolate reductase gene polymorphism in endometrial cancer: A systematic review and meta-analysis.

    PubMed

    Wang, Xian-Jun; Xu, Li-Hui; Chen, Yue-Ming; Luo, Li; Tu, Qiao-Feng; Mei, Jin

    2015-10-01

    We conducted a meta-analysis of case-controlled prospective or retrospective studies to assess the effect of MTHFR polymorphisms on the risk of developing endometrial cancer. PubMed, Cochrane, EMBASE, and ISI Web of Knowledge were searched (up to March 2014) for prospective or retrospective case-controlled studies that investigated the association of three MTHFR polymorphisms (rs180113 [C677T], rs1801131 [A1289C], and rs2274976 [G1793A]) with endometrial cancer. The patient population included subjects from three separate countries: China, Spain, and the USA. Only one study reported quantitative findings for MTHFR G1793A and, consequently, this polymorphism was not evaluated in our analysis. There were no significant associations of any MTHFR C677T or MTHFR A1298C alleles or genotypes with endometrial cancer (all p > 0.300). This meta-analysis does not support the association of endometrial cancer with two common MTHFR polymorphisms from this patient population. Copyright © 2015. Published by Elsevier B.V.

  17. [A case-control study on the polymorphisms of methylenetetrahydrofolate reductase 1298A-->C and susceptibility of esophageal cancer].

    PubMed

    Gao, Chang-ming; Toshiro, Takezaki; Wu, Jian-zhong; Cao, Hai-xia; Liu, Yan-ting; Ding, Jian-hua; Li, Su-ping; Su, Ping; Hu, Xu; Kai, Hai-tao; Kazuo, Tajima

    2004-04-01

    To investigate the relationship between polymorphisms of methylenetetra-hydrofolate reductase gene 1298A-->C (MTHFR 1298A-->C) and its susceptibility of esophageal cancer (EC). We conducted a case-control study with 141 cases of EC and 228 population-based controls in Huaian city of Jiangsu province, China. Epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects. MTHFR genotypes were identified by polymerase chain reaction. (1) The frequency of MTHFR 1298AA, AC and CC genotype were 63.8%, 34.0% and 2.1% in EC and 71.9%, 28.1% and 0.0% in controls, respectively (chi(2)(MH) = 6.69, P = 0.035). The frequency of the MTHFR 1298C allele was 0.19 for EC and 0.14 for controls. (2) Individuals having MTHFR 1298C allele and smoking habit were at a significantly higher risk of developing EC (adjusted OR = 3.48, 95% CI: 1.57 - 7.71) compared with those who having AA genotype but no smoking habit. Individuals having MTHFR 1298C allele and habit of frequent alcohol drinking were at an increased risk of developing EC (adjusted OR = 2.91, 95% CI: 1.20 - 7.08) compared with those with AA genotype and low consumption of alcohol. Individuals having MTHFR 1298C allele but no habit of tea drinking had a 3.52-fold (95% CI: 1.64 - 7.54) increased risk of developing EC compared with tea drinkers with AA genotype. As compared with subjects having AA genotype, low consumption of alcohol, no smoking habit but having habit of drinking tea, the individuals having 1298C allele, habits of frequent alcohol drinking, smoking but no habit of tea drinking had a 12.64-folds (95% CI: 1.39 - 114.65) increased risk of developing EC. Results in the present study suggested that there was a coordinated effect between MTHFR 1298 genotypes and habits of smoking, alcohol drinking and tea consumption in the development of EC.

  18. Association of methylenetetrahydrofolate reductase gene 677C > T polymorphism and Down syndrome.

    PubMed

    Costa-Lima, Marcelo Aguiar; Amorim, Márcia Rodrigues; Orioli, Iêda Maria

    2013-03-01

    The association between Down syndrome (DS) and maternal polymorphisms in genes encoding folic acid metabolizing enzymes remains a controversial issue. A meta-analysis was performed to evaluate the association of maternal MTHFR 677C > T polymorphism and the risk of having a child with DS. Case-control studies were screened from major literature databases. Twenty articles from 13 countries worldwide, with a total of 2,101 DS and 2,702 control mothers, attended the inclusion criteria. We found a 50 % increase for the association of maternal homozygous TT genotype and DS in both fixed (OR = 1.51; 95 % CI 1.22-1.87) and random effects models (OR 1.54; 95 % 1.15-2.05). Similarly, a significant pooled OR was found for the heterozygote CT, with an OR 1.26; 95 % CI 1.10-1.43 (fixed effects model) and OR 1.28; 95 % 1.08-1.51 (random effects model). As ultra-violet B solar radiation highly depends on latitude, and can promote, in less pigmented skin, intravascular folate photolysis, we stratified the analysis by latitude region, defining as Tropical (between 23.5(°) S and 23.5(°) N), Sub-Tropical (between 23.5(°) and 40(°) N and S), and Northern (≥ 40(o) N). Significant association was only found for Sub-Tropical area, both using fixed and random effect models. In conclusion, MTHFR 677C > T polymorphism is a moderate risk factor for DS for some populations, and populations located in Sub-Tropical region seem to be at greater risk. Latitude, ethnicity, skin pigmentation, and red blood cell folate are important variables to be considered in future studies.

  19. Methylenetetrahydrofolate reductase gene polymorphisms and the risk of anencephaly in Mexico.

    PubMed

    Muñoz, Julia Blanco; Lacasaña, Marina; Cavazos, Ricardo García; Borja-Aburto, Victor Hugo; Galavíz-Hernández, Carlos; Garduño, Clemente Aguilar

    2007-06-01

    The precise etiology of neural tube defects (NTDs) is not known. There is some evidence that mutations in MTHFR gene provide susceptibility to NTDs in some populations; however, other studies have not found this association. One of the problems with previous studies is that they treat NTDs as a homogeneous group, when specific defects could have different etiologies. We conducted a case-control study specifically for anencephaly, based on the Mexican Epidemiological Surveillance System of Neural Tube Defects to evaluate its association with maternal MTHFR 677C > T and 1298A > C polymorphisms, in three states with high frequencies of NTDs: Puebla, Estado de México and Guerrero. We interviewed and collected blood samples from 118 case mothers and 112 control mothers. The questionnaire included information on their reproductive history, socioeconomic characteristics, prenatal care, tobacco and alcohol use, presence of chronic diseases, acute illnesses and fever, consumption of multivitamins and drugs during the periconceptional period. After adjusting for potential confounders, the risk from the mutated homozygous mothers (677TT genotype) was significantly higher than that from mothers with 677CC genotype (OR 3.16, 95% CI 1.29-7.73); in the case of the heterozygous mothers, an increased risk of anencephaly was observed, even though this was not statistically significant (OR 1.81 95% CI 0.78-4.25). The association found between maternal 677TT genotype and anencephaly and the elevated presence of the 677T allele among Mexican women of fertile age urges intensifying folic acid supplementation which has proved to modify this genetic risk in other populations.

  20. Association between methylenetetrahydrofolate reductase (MTHFR) polymorphisms and susceptibility to Graves' ophthalmopathy.

    PubMed

    Lee, Jae Yeun; Kim, Nam Keun; Cho, Yong Wook; Lew, Helen

    2016-09-01

    The pathogenesis of Graves' ophthalmopathy (GO) remains to be entirely elucidated. The present study aimed to determine the association between phenotypic expression of the MTHFR gene and susceptibility to GO in patients with Graves' disease (GD). A prospective case‑controlled study was conducted with 122 patients with GD and GO (n=72) or without GO (n=50) and 100 healthy controls in South Korea. Patient history, including smoking, nutritional status, thyroid function and antithyroid antibodies were investigated and clinical activity score, VISA classification (which includes vision, inflammation, strabismus and appearance/exposure) and orbit computed tomography were evaluated. Fasting plasma total homocysteine (tHcy) concentration was measured, and genotype analysis of the MTHFR gene was conducted. The TT homozygous genotype was associated with a two‑fold increased risk of GO [adjusted odds ratio (AOR), 2.19; 95% confidence interval (CI), 0.78‑6.14]. However, this result was not significant. The TT genotype significantly increased the risk of GO compared with that in healthy controls (AOR, 2.92; 95% CI, 1.11‑7.65). The MTHFR 677CT/1298AA genotype decreased the risk of GO in patients with GD (AOR, 0.26; 95% CI, 0.08‑0.91). tHcy levels in patients with GD without GO were significantly higher than in patients with GO, however, they were within the normal limit. The current study identified an association between MTHFR polymorphisms and GO. These results will aid understanding of the pathogenesis of GO and facilitate development of genetic therapeutic strategies.

  1. Association of the C677T polymorphism in the human methylenetetrahydrofolate reductase (MTHFR) gene with the genetic predisposition for type 2 diabetes mellitus in a Moroccan population.

    PubMed

    Benrahma, Houda; Abidi, Omar; Melouk, Leila; Ajjemami, Maria; Rouba, Hassan; Chadli, Asmaa; Oudghiri, Mounia; Farouqui, Ahmed; Barakat, Abdelhamid

    2012-05-01

    Type 2 diabetes mellitus (T2DM) is a major public health problem around the world. The C677T and A1298C polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) gene have been reported to be associated with T2DM and its complications. This study aimed to investigate this association in the Moroccan population. A case-control study was performed among 282 Moroccan diabetic patients and 232 healthy controls. The MTHFR C677T and A1298C polymorphisms were genotyped by polymerase chain reaction, followed by enzymatic digestion with HinfI and MboII enzymes, respectively. There was a significant association between C677T polymorphism and T2DM in both additive and dominant models. In addition, the 677T allele frequency differed significantly between the diabetic and control groups (26.06% vs. 33.20%, respectively). However, no significant association was found between A1298C polymorphism and T2DM. The frequencies of combined genotypes 677CC/1298AA and 677CT/1298AC differed significantly between the diabetic and control groups (32.62% vs. 20.61% and 9.57% vs. 17.55%, respectively). These results show an evident association between the MTHFR C677T polymorphism and T2DM in Moroccan patients but no significant association with the MTHFR A1298C polymorphism.

  2. The methylenetetrahydrofolate reductase (MTHFR) 677 C>T polymorphism increases the risk of developing chronic myeloid leukemia-a case-control study.

    PubMed

    Bănescu, Claudia; Iancu, Mihaela; Trifa, Adrian P; Macarie, Ioan; Dima, Delia; Dobreanu, Minodora

    2015-04-01

    The methylenetetrahydrofolate reductase (MTHFR) 677 C>T and 1298 A>C polymorphisms are associated with variations in folate levels, a phenomenon linked to the development of various malignancies. The aim of this study was to investigate the influence of the 677 C>T and 1298 A>C polymorphisms in the MTHFR gene on the risk of developing chronic myeloid leukemia (CML). Our study included 151 patients with CML and 305 controls. The MTHFR 677 C>T and 1298 A>C polymorphisms were investigated by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and allele-specific PCR techniques. The CT and TT genotypes of the MTHFR 677 C>T polymorphism were associated with an increased risk of developing CML (odds ratio (OR) = 1.556, 95% confidence interval (CI) = 1.017-2.381, p value = 0.041, and OR = 1.897, 95% CI = 1.046-3.44, p value = 0.035, respectively). No association was observed between the prognostic factors (blasts, basophils, additional chromosomal abnormalities, EUTOS score, Sokal and Hasford risk groups) and the MTHFR 677 C>T and 1298 A>C variant genotypes in CML patients. Our study shows that the MTHFR 677 C>T polymorphism is significantly associated with the risk of CML in Romanian patients.

  3. Methylenetetrahydrofolate reductase (MTHFR) 677C/T polymorphism is associated with antipsychotic-induced weight gain in first-episode schizophrenia.

    PubMed

    Srisawat, Umarat; Reynolds, Gavin P; Zhang, Zhi Jun; Zhang, Xiang Rong; Arranz, Belen; San, Luis; Dalton, Caroline F

    2014-03-01

    Genetic variants of the methylenetetrahydrofolate reductase (MTHFR) gene involved in homocysteine metabolism may be important predictors of antipsychotic drug-induced weight gain (AIWG). We tested whether two functional MTHFR polymorphisms are related to AIWG. Weight gain was studied in two cohorts of first-episode, initially drug-naive schizophrenia patients; Chinese Han (n = 182) and Spanish Caucasians (n = 72) receiving antipsychotics for 10 wk and 3 months respectively. Blood DNA was genotyped for 677C/T and 1298A/C MTHFR polymorphisms. Patients with the 677 CC genotype had a significantly greater increase in BMI compared to T-allele carriers in both Chinese (p = 0.012) and Spanish (p = 0.017) samples. The 677C/T MTHFR polymorphism showed an additive effect, but no significant interaction, with the -759C/T HTR2C polymorphism previously associated with AIWG. These results suggest that the 677C/T MTHFR polymorphism might, along with the -759C/T HTR2C polymorphism and other genetic factors, provide a useful marker for the important and limiting side effect of AIWG.

  4. C677T polymorphism of the methylenetetrahydrofolate reductase gene does not affect folic acid, vitamin B12, and homocysteine serum levels in Turkish children with neural tube defects.

    PubMed

    Erdogan, M O; Yildiz, S H; Solak, M; Eser, O; Cosar, E; Eser, B; Koken, R; Buyukbas, S

    2010-06-22

    Association between neural tube defects (NTDs) and C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene was suspected, because the MTHFR gene codes for a key enzyme in folate metabolism. Its deficiency usually leads to significant reductions in plasma concentrations of folate, vitamin B(12) and methionine, whereas homocysteine levels are increased. We examined folate, vitamin B(12) and homocysteine serum concentrations and polymorphism of the C677T MTHFR gene in Turkish children with neural tube defects. Thirty-three children with NTDs, 26 mothers and 48 healthy individuals were studied. C677T MTHFR polymorphism was determined by melting curve analyses (LightCycler). The levels of folate, vitamin B(12) and homocysteine serum concentrations in NTDs were evaluated and compared, along with information concerning alleles of the MTHFR gene. C677T allele frequencies in NTD children and their mothers were similar to those found in controls. Serum folate and vitamin B(12) concentrations were significantly higher in NTD children than that of controls. Serum homocysteine concentrations were not significantly higher in NTD children and mothers. We concluded that C677T MTHFR gene polymorphism does not affect folic acid, vitamin B(12) and homocysteine metabolism in Turkish children with NTDs. C677T polymorphism of the MTHFR gene cannot be regarded as a major risk factor for NTDs in Turkish children.

  5. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and susceptibility to diabetic nephropathy in Chinese type 2 diabetic patients: a meta-analysis.

    PubMed

    Chang, Wei-wei; Zhang, Liu; Yao, Ying-shui; Su, Hong; Jin, Yue-long; Chen, Yan

    2013-08-01

    The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and diabetic nephropathy (DN) or diabetes mellitus (DM) risk has been widely reported, but the results are still debatable. To investigate the role of MTHFR C677T polymorphism on DM or DN, 13 separate studies in the Chinese population on the relation between MTHFR C677T polymorphism and DM or DN were analyzed by a meta-analysis. Five genetic models were used to estimate the association between MTHFR C677T polymorphism and the risk of DM or DN. Overall, our meta-analysis for DN versus healthy controls produced significant results for all genetic contrasts except for the co-dominant model (allele contrast: OR = 2.24, 95%CI: 1.88-2.65, p < 0.00001, Pheterogeneity = 0.49). However, the meta-analysis for DM versus healthy controls produced non-significant results for all contrasts (allele contrast: OR = 1.12, 95%CI: 0.92-1.35, p = 0.25, Pheterogeneity = 0.07). In addition, the meta-analysis for DM versus DN produced significant results for all contrasts (allele contrast: OR = 1.88, 95%CI: 1.65-2.15, p < 0.00001, Pheterogeneity = 0.83). The current meta-analysis suggested that MTHFR C677T polymorphism might influence DN risk, but not for DM in the Chinese population.

  6. Association between methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms and essential hypertension: a systematic review and meta-analysis.

    PubMed

    Wu, Yi-Le; Hu, Cai-Yun; Lu, Shan-Shan; Gong, Feng-Feng; Feng, Fang; Qian, Zhen-Zhong; Ding, Xiu-Xiu; Yang, Hui-Yun; Sun, Ye-Huan

    2014-12-01

    Many studies have investigated the role of 5,10-methylenetetrahydrofolate reductase gene (MTHFR) C677T/A1298C polymorphisms in essential hypertension (EH), but results are inconclusive. The purpose of this meta-analysis was to clarify the effects of MTHFR C677T/A1298C polymorphisms on the risk of EH. Electronic databases were searched to identify relevant studies published until January 2014. Data were extracted by two independent authors. Odds ratios (ORs) with 95%confidence intervals (CIs) were used to assess the association between MTHFR C677T/A1298C polymorphisms and the risk of EH using random effect models or fixed effect models. Finally,30 studies with 5207 cases and 5383 controls were included for C677T polymorphism and 6 studies with 1009 cases and 994 controls were included for A1298C polymorphism. Meta-analysis results indicated that MTHFR C677T polymorphism contributed to an increased risk of EH (for T vs. C: OR=1.30, 95%CI=1.18–1.43; for TT+CT vs. CC: OR=1.34, 95%CI=1.24–1.46; for TT vs. CC: OR=1.62, 95%CI=1.32–1.99; for TT vs. CT+CC: OR=1.41, 95%CI=1.26–1.59). However, no significant association was detected between MTHFR A1298C polymorphism and the risk of EH. This meta-analysis supports that MTHFR C677T polymorphism plays a role in developing EH. MTHFR A1298C polymorphism may not be associated with an increased risk of EH. Further large and well-designed studies are warranted to confirm these findings.

  7. Creatine kinase MM TaqI and methylenetetrahydrofolate reductase C677T and A1298C gene polymorphisms influence exercise-induced C-reactive protein levels.

    PubMed

    Miranda-Vilela, Ana Luisa; Akimoto, Arthur K; Lordelo, Graciana S; Pereira, Luiz C S; Grisolia, Cesar K; Klautau-Guimarães, Maria de Nazaré

    2012-03-01

    Physical training induces beneficial adaptations, but exhausting exercise increases reactive oxygen species, which can cause muscular injuries with consequent inflammatory processes, implying jeopardized performance and possibly overtraining. Acute strenuous exercise almost certainly exceeds the benefits of physical activity; it can compromise performance and may contribute to increased future risk of cardiovascular disease (CVD) in athletes. Polymorphisms in the muscle-type creatine kinase (CK-MM) gene may influence performance and adaptation to training, while many potentially significant genetic variants are reported as risk factors for CVD. Therefore, we investigated the influence of polymorphisms in CK-MM TaqI and NcoI, methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and C-reactive protein (CRP G1059C) genes on exercise-induced damage and inflammation markers. Blood samples were taken immediately after a race (of at least 4 km) that took place outdoors on flat tracks, and were submitted to genotyping and biochemical evaluation of aspartate aminotransferase (AST), CK, CRP and high-sensitivity CRP (hs-CRP). CK-MM TaqI polymorphism significantly influenced results of AST, CK and hs-CRP, and an association between MTHFR C677T and A1298C with CRP level was found, although these levels did not exceed reference values. The results indicate that these polymorphisms can indirectly influence performance, contribute to higher susceptibility to exercise-induced inflammation or protection against it, and perhaps affect future risks of CVD in athletes.

  8. Creatine kinase MM TaqI and methylenetetrahydrofolate reductase C677T and A1298C gene polymorphisms influence exercise-induced C-reactive protein levels.

    PubMed

    Miranda-Vilela, Ana Luisa; Akimoto, Arthur K; Lordelo, Graciana S; Pereira, Luiz C S; Grisolia, Cesar K; Klautau-Guimarães, Maria de Nazaré

    2012-01-01

    Physical training induces beneficial adaptations, but exhausting exercise increases reactive oxygen species, which can cause muscular injuries with consequent inflammatory processes, implying jeopardized performance and possibly overtraining. Acute strenuous exercise almost certainly exceeds the benefits of physical activity; it can compromise performance and may contribute to increased future risk of cardiovascular disease (CVD) in athletes. Polymorphisms in the muscle-type creatine kinase (CK-MM) gene may influence performance and adaptation to training, while many potentially significant genetic variants are reported as risk factors for CVD. Therefore, we investigated the influence of polymorphisms in CK-MM TaqI and NcoI, methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and C-reactive protein (CRP G1059C) genes on exercise-induced damage and inflammation markers. Blood samples were taken immediately after a race (of at least 4 km) that took place outdoors on flat tracks, and were submitted to genotyping and biochemical evaluation of aspartate aminotransferase (AST), CK, CRP and high-sensitivity CRP (hs-CRP). CK-MM TaqI polymorphism significantly influenced results of AST, CK and hs-CRP, and an association between MTHFR C677T and A1298C with CRP level was found, although these levels did not exceed reference values. Results indicate that these polymorphisms can indirectly influence performance, contribute to higher susceptibility to exercise-induced inflammation or protection against it, and perhaps affect future risks of CVD in athletes.

  9. A duplex polymerase chain reaction-restriction fragment length polymorphism for rapid screening of methylenetetrahydrofolate reductase gene variants: Genotyping in acute leukemia.

    PubMed

    Frikha, Rim; Bouayed, Nouha; Ben Rhouma, Bochra; Keskes, Leila; Rebai, Tarek

    2017-04-04

    Methylenetetrahydrofolate reductase (MTHFR; NM_005957.4) is the key enzyme for folate metabolism which plays in DNA biosynthesis and the epigenetic process of DNA methylation. MTHFR gene polymorphisms, the c. 677C>T and c. 1298A>C have been implicated as risk factors for several types of cancers as the acute leukemia. We have optimized a duplex polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP) for the simultaneous detection of both variants in acute leukemia patients, from Tunisia. Genomic DNA was extracted from EDTA-anticoagulant blood samples from a total of 50 patients suffering from acute leukemia (AL). After DNA extraction, the polymerase chain reaction using specific primers, designed using Primer 3 Software. Restriction Fragment Length Polymorphism (RFLP) was performed in two separate tubes followed by agarose gel electrophoresis. This new method has proved to be a rapid, simple, and reliable method that should facilitate high throughput genotyping of MTHFR polymorphisms in acute leukemia. © 2017 Wiley Periodicals, Inc.

  10. Association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with preterm delivery and placental abruption: a systematic review and meta-analysis.

    PubMed

    Chen, Jian; Chen, Liang; Zhu, Li-Hua; Zhang, Si-Tong; Wu, Yi-Le

    2016-02-01

    The aim of this study was to summarize evidence on the association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and odds of preterm delivery and placental abruption. PubMed, EMBASE, CBM (Chinese Biomedical Database) and CNKI (Chinese National Knowledge Infrastructure) were searched to identify eligible studies published in English or Chinese before 12 August 2014. The pooled odds ratios (ORs) with 95% confidence intervals were estimated for the association of MTHFR C677T polymorphism with preterm delivery and placental abruption using random effects models. A total of 22 studies that met inclusion and exclusion criteria were included in this meta-analysis. Regardless of the genetic model tested we found no statistically significant association of MTHFR C677T polymorphism with preterm delivery or placental abruption. Funnel plots inspections, Begg's test and Egger's test did not show evidence of publication bias. This meta-analysis demonstrated that overall there was no association of MTHFR C677T polymorphism with preterm delivery or placental abruption. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

  11. Associations of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms with genetic susceptibility to rheumatoid arthritis: a meta-analysis.

    PubMed

    Cen, Han; Huang, Hua; Zhang, Li-Na; Liu, Li-Ya; Zhou, Li; Xin, Xia-Fei; Zhuo, Ren-Jie

    2017-02-01

    The aim of our study was to conduct a meta-analysis to assess whether combined evidence shows associations between C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase (MTHFR) and genetic susceptibility to rheumatoid arthritis (RA). A total of 11 articles involving 20 comparisons were included, containing 12 comparisons for the MTHFR C677T polymorphism and 8 comparisons for the MTHFR A1298C polymorphism. Significant evidence was detected for the association of RA susceptibility with the MTHFR C677T polymorphism T allele under allelic contrast and dominant model in Asians (T versus C, OR = 1.300, 95 % CI = 1.104-1.531, p = 0.002; TT + CT versus CC, OR = 1.495, 95 % CI = 1.187-1.882, p = 0.001). Significant association between RA susceptibility and the MTHFR A1298C polymorphism A allele under recessive model was found in the overall meta-analysis (AA versus AC + CC, OR = 1.281, 95 % CI = 1.048-1.565, p = 0.016). Our meta-analysis results demonstrate that the MTHFR C677T polymorphism is involved in the genetic susceptibility of RA in Asians, and the MTHFR A1298C polymorphism is associated with genetic susceptibility to RA in the overall population. Given the paucity of studies, especially in non-Asian populations, further studies with larger sample sizes are required to elucidate the role of MTHFR polymorphisms in the genetic basis of RA in different ethnic populations.

  12. Methylenetetrahydrofolate reductase polymorphism (677 C>T) predicts long time to progression in metastatic colon cancer treated with 5-fluorouracil and folinic acid.

    PubMed

    Castillo-Fernández, Omar; Santibáñez, Miguel; Bauza, Aldo; Calderillo, Germán; Castro, Clementina; Herrera, Roberto; Serrano, Alberto; Arrieta, Oscar; Herrera, Luis A

    2010-08-01

    Fluoropyrimidine-based chemotherapy is the most common treatment for unresectable metastatic colorectal cancer (m-CRC). Therapy with 5-FU/folinic acid (FA) continues to be a standard treatment in developing countries. Pharmacogenomics allows the tailoring of cancer therapy to the patient. The polymorphism 677C>T of the methylenetetrahydrofolate reductase (MTHFR) gene seems to influence the effectiveness of treatment with 5-FU. We undertook this study to evaluate the frequency of MTHFR 677C>T polymorphism and its relationship to the time to progression (TTP) and overall survival (OS) in m-CRC treated with 5-FU/FA. The MTHFR 677C>T polymorphism was determined using PCR and allele-specific digestion. The clinical variables, TTP and OS, were analyzed in each case and compared between wild-type and variant polymorphic groups. Among 34 patients (12 males and 22 females), we detected eight wild-type homozygous patients (CC; 24%), nine variant homozygous (TT; 26%), and 17 heterozygous (CT; 50%) individuals. The median TTP in patients with the MTHFR 677 CC, CT, and TT genotypes was 3.43, 4.77, and 4.80 months, respectively (p = 0.047, log rank). A longer TTP was observed in patients with polymorphic variant (CT and TT) compared with the wild-type homozygous patients (4.80 vs. 3.43 months; p = 0.031, log rank). In this study, the frequency of the MTHFR 677C>T polymorphism is 50% among m-CRC Mexican patients. The results of this study appear to show that the presence of the MTHFR 677C>T polymorphism is associated with longer TTP and OS in m-CRC treated with 5-FU/FA. Copyright © 2010 IMSS. Published by Elsevier Inc. All rights reserved.

  13. Association of a miR-34b binding site single nucleotide polymorphism in the 3'-untranslated region of the methylenetetrahydrofolate reductase gene with susceptibility to male infertility.

    PubMed

    Zhang, W; Lin, W-Q; Cao, H-F; Li, C-Y; Li, F

    2015-10-09

    This study aims to explore the possible associations between a genetic variation in the miR-34b binding site in the 3'-untranslated region (UTR) of the methylenetetrahydrofolate reductase (MTHFR) gene (rs55763075) with male infertility in a Chinese population. Genotype distributions of the rs55763075 single nucleotide polymorphism were investigated by polymerase chain reaction and direct sequencing in a Chinese cohort that included 464 infertile men with idiopathic azoospermia or oligospermia and 458 controls with normal fertility. Overall, no significant differences in the distributions of the genotypes of the MTHFR rs55763075 polymorphism were detected between the infertility and control groups. A statistically significant increased risk of male infertility was found for carriers of the rs55763075 AA genotype when compared with homozygous carriers of the rs55763075 GG genotype in the azoospermia subgroup (OR = 1.721; 95% CI = 1.055-2.807; P = 0.031). Furthermore, we found that rs55763075 was associated with folate and homocysteine levels in patients with idiopathic azoospermia. Our results indicated that the MTHFR 3'-UTR rs55763075 polymorphism might modify the susceptibility to male infertility with idiopathic azoospermia.

  14. Methylenetetrahydrofolate reductase C677T and A1298C gene polymorphisms in oral squamous cell carcinoma in south-east Iran.

    PubMed

    Miri-Moghaddam, Ebrahim; Saravani, Shirin; Garme, Yasamn; Khosravi, Arezoo; Bazi, Ali; Motazedian, Jamaledin

    2016-02-01

    Methylenetetrahydrofolate reductase (MTHFR) gene encodes an essential enzyme involving in folate metabolism. Due to the role of folate in DNA integrity, polymorphisms of MTHFR are interesting targets for cancer risk studies. Our goal was to evaluate the prevalence of MTHFR C677T and A1298T single nucleotide polymorphisms in oral squamous cell carcinoma (OSCC). The study was conducted on 57 OSCC patients diagnosed within 2004-2013 along with 62 non-OSCC subjects. DNA was extracted by standard kit protocol. Subsequently, tetra-ARMS (amplification refractory mutation system)-PCR was applied to identify the selected polymorphisms. Data showed that CT and TT genotypes of C677T polymorphisms significantly increased the risk of OSCC [odds ratio (OR) = 2.2, 95% CI: 1-5, P = 0.04]. Although allelic distribution was not significantly different between patients and controls, T allele of C677T polymorphism was closely associated with the risk of OSCC (OR = 2.5; 95% CI: 0.9-6.9; P = 0.07). Results indicated that C677T/A1298C: CC/AC and C677T/A1298C: CC/AA haplotypes were the most common combinations in OSCC patient and control groups, respectively. (OR = 1.5, 95% CI: 0.6-3.8, P > 0.05). Our results highlight the possible impact of C677T polymorphism in increasing the risk of OSCC development. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. [Clinical course of acute coronary syndrome in dependence on containing of homozystein and С677Т methylenetetrahydrofolate reductase gene polymorphism].

    PubMed

    Pristupa, L N; Grek, A V; Ataman, Iu A; Orlovskiy, A V; Opolonska, N A

    2015-01-01

    Nowadays to a numerous factors of IHD development risks hyperhomocysteinemia (HHc), C-reactive protein, fibrogen, as well as genetic disorders are relating. With development of IHD and its complications associated methylentetrahudrofolate reductase gene mutation of С677Т polymorphism. The purpose of the investigation was studying the connection between acute coronary syndrome severity (ACS) in dependence on plasma homocysteine containing and genotype by С677Т polymorphism MTHFR gene. Examined: 161 patients with ACS and 87 almost healthy people. Identification of 4th exon allelic polymorphism MTHFR С677Т gene (rs1801133) was conducted with method of polymerase chain reaction, the investigation of homocysteine containing with immunoenzymated method. The statistic analyze was performed with using of SPSS - 17 programme. According to results of study patients with ACS of homozygote by minor allele T С677Т MTHFR gene polymorphism by main allele C and heterozygote were associated with high homocysteine containing in plasma. While frequencies of T/T genotype was reliably higher in patients with ACS with segment ST elevation and complicated course compare with patients with ACS with segment ST elevation and non-complicated course and ACS without climbs of segment ST. Also, statistically reliable difference in genotypes distribution by C677T MTHFR gene polymorphism in dependence on homocysteine plasma level and clinical course of ACS severity were established.

  16. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and high plasma homocysteine in chronic hepatitis C (CHC) infected patients from the Northeast of Brazil

    PubMed Central

    2011-01-01

    Background/Aim Hyperhomocysteinemia due to Methylenetetrahydrofolate Reductase (MTHFR) gene, in particular the C677T (Ala222Val) polymorphism were recently associated to steatosis and fibrosis. We analyzed the frequency of MTHFR gene in a cross-sectional study of patients affected by Chronic Hepatitis C (CHC) from Northeast of Brazil. Method One hundred seven-four untreated patients with CHC were genotyped for the C677T MTHFR. Genomic DNA was extracted from peripheral blood cells and the C677T MTHFR polymorphism was identified by PCR-RFLP. The homocysteine (Hcy) levels were determined by chemiluminescence method. All patients were negative for markers of Wilson's disease, hemochromatosis and autoimmune diseases and have current and past daily alcohol intake less than 100 g/week. Results Among subjects infected with CHC genotype non-1 the frequency of MTHFR genotypes TT was 9.8% versus 4.4% genotype 1 (p = 0.01). Nevertheless, association was found between the MTHFR genotype TT × CT/CC polymorphism and the degree of steatosis and fibrosis in both hepatitis C genotype (p < 0.05). A significant difference was found on plasma Hcy levels in patients with steatosis regardless of HCV genotype (p = 0.03). Conclusion Our results indicate that plasma Hcy levels is highly prevalent in subjects with chronic hepatits C with steatosis regardless of HCV genotype and vitamin deficiency. The presence of genotype TT of MTHFR C677T polymorphism was more common in CHC genotype non-1 infected patient regardless of histopathological classification and genotype TT+CT frequencies were significant in the presence of fibrosis grade 1+2 and of steatosis in CHC infected patients from the northeast of Brazil regardless of HCV genotype. The genetic susceptibility of MTHFR C677T polymorphism should be confirmed in a large population. PMID:21854603

  17. Are the methylenetetrahydrofolate reductase 1298 and 677 gene polymorphisms related to optic glioma and hamartoma risk in neurofibromatosis type 1 patients?

    PubMed

    Tanyıldız, Hikmet Gülşah; Yeşil, Şule; Bozkurt, Ceyhun; Çandır, Mehmet Onur; Akpınar-Tekgündüz, Sibel; Toprak, Şule; Yüksel, Deniz; Şahin, Gürses

    2016-01-01

    The methylenetetrahydrofolate reductase (MTHFR) gene plays a key role in carcinogenesis through its effects on DNA synthesis and methylation and also has a significant role in the etiology of many disorders, such as diabetes, migraine, and cardiovascular disease. Neurofibromatoses (NF) are autosomal dominant inherited diseases that can affect tissues such as bone and skin and predispose individuals to tumor development in various parts of the nervous system or body. Optic nerve glioma and brain tumors are common in children with NF, and leukemia and lymphoma incidence is also higher than normal. We therefore aimed to investigate the possible relationship between the MTHFR gene polymorphism and accompanying tumors such as neurofibroma, hamartoma, and optic glioma in children with NF1 found to have the MTHFR 677 and MTHFR 1298 gene polymorphism in this study. We included 55 pediatric patients diagnosed with NF1 between 2005 and 2014 in the study group. The control group included 44 healthy subjects without acute or chronic disease findings. A significant relationship was found between the MTHFR A1298C polymorphism and the incidence of optic glioma (p=0.014) (AA vs. AC: OR 11, 95% CI 1.27-95.17; AA vs. CC: OR 7.33, 95% CI 0.35-150.70). We also found a significant relationship between the MTHFR C1298C polymorphism and the incidence of hamartoma (p=0.019) (AA vs. AC: OR 2.12, 95% CI 0.662-6.809; p=0.203). Epilepsy incidence was high in subjects with MTHFR C677C. The MTHFR A1298C, C1298C, and C677C gene polymorphisms can be associated with a higher optic glioma, hamartoma, and epilepsy incidence, respectively, in patients diagnosed with neurofibromatosis type 1.

  18. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and high plasma homocysteine in chronic hepatitis C (CHC) infected patients from the Northeast of Brazil.

    PubMed

    Siqueira, Erika R F; Oliveira, Cláudia P M S; Muniz, Maria T C; Silva, Filipe; Pereira, Leila M M B; Carrilho, Flair J

    2011-08-19

    Hyperhomocysteinemia due to Methylenetetrahydrofolate Reductase (MTHFR) gene, in particular the C677T (Ala222Val) polymorphism were recently associated to steatosis and fibrosis. We analyzed the frequency of MTHFR gene in a cross-sectional study of patients affected by Chronic Hepatitis C (CHC) from Northeast of Brazil. One hundred seven-four untreated patients with CHC were genotyped for the C677T MTHFR. Genomic DNA was extracted from peripheral blood cells and the C677T MTHFR polymorphism was identified by PCR-RFLP. The homocysteine (Hcy) levels were determined by chemiluminescence method. All patients were negative for markers of Wilson's disease, hemochromatosis and autoimmune diseases and have current and past daily alcohol intake less than 100 g/week. Among subjects infected with CHC genotype non-1 the frequency of MTHFR genotypes TT was 9.8% versus 4.4% genotype 1 (p = 0.01). Nevertheless, association was found between the MTHFR genotype TT × CT/CC polymorphism and the degree of steatosis and fibrosis in both hepatitis C genotype (p < 0.05). A significant difference was found on plasma Hcy levels in patients with steatosis regardless of HCV genotype (p = 0.03). Our results indicate that plasma Hcy levels is highly prevalent in subjects with chronic hepatits C with steatosis regardless of HCV genotype and vitamin deficiency. The presence of genotype TT of MTHFR C677T polymorphism was more common in CHC genotype non-1 infected patient regardless of histopathological classification and genotype TT+CT frequencies were significant in the presence of fibrosis grade 1+2 and of steatosis in CHC infected patients from the northeast of Brazil regardless of HCV genotype. The genetic susceptibility of MTHFR C677T polymorphism should be confirmed in a large population.

  19. Genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene Ala222Val and susceptibility to ovary cancer: a systematic review and meta-analysis.

    PubMed

    Pan, Xinwei; Lu, Yan; Long, Ying; Yao, Desheng

    2014-03-01

    Many studies have reported the role of methylenetetrahydrofolate reductase (MTHFR) gene Ala222Val polymorphism with ovary cancer risk, but the results remained controversial. To derive a more precise estimation of the relationship, a meta-analysis was performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association between MTHFR Ala222Val polymorphism and ovary cancer risk. A total of 8 studies including 3,723 cases and 4,001 controls were also involved in this meta-analysis. When all the eligible studies were pooled into this meta-analysis, no significant association between ovary cancer risk and MTHFR Ala222Val polymorphism was found in all genetic models [codominant model: OR = 0.980, 95% CI = 0.756-1.270, P h = 0.088, P = 0.877; dominant model: OR = 1.022, 95% CI = 0.864-1.208, P h = 0.033, P = 0.803; recessive model: OR = 1.050, 95% CI = 0.803-1.373, P h = 0.032, P = 0.723; allele comparison model: OR = 1.028, 95% CI = 0.898-1.178, P h = 0.012, P = 0.685]. In the stratified analysis by ethnicity, no evidence of any associations of this polymorphism with ovary cancer was found in the Caucasian populations. Our meta-analysis supports that the MTHFR Ala222Val polymorphism is not contributed to the risk of ovary cancer from currently available evidence.

  20. Genetic polymorphisms in the methylenetetrahydrofolate reductase gene (MTHFR) and risk of vitiligo in Han Chinese populations: a genotype-phenotype correlation study.

    PubMed

    Chen, J-X; Shi, Q; Wang, X-W; Guo, S; Dai, W; Li, K; Song, P; Wei, C; Wang, G; Li, C-Y; Gao, T-W

    2014-05-01

    Recent evidence has revealed an elevation of total homocysteine (tHcy) in patients with vitiligo. Methylenetetrahydrofolate reductase (MTHFR) is one of the main enzymes regulating homocysteine (Hcy) metabolism. Thus, polymorphisms of MTHFR could potentially contribute to the development of vitiligo by affecting MTHFR activity and tHcy levels. To evaluate the potential association between MTHFR polymorphisms and vitiligo susceptibility. In total, 1000 patients with vitiligo and 1000 age- and sex-matched controls were enrolled in this hospital-based case-control study. Two single-nucleotide polymorphisms of the MTHFR gene (rs1801133 C>T and rs1801131 A>C) were selected and genotyped using polymerase chain reaction (PCR)-restriction fragment length polymorphism and allele-specific PCR, respectively. The MTHFR activity concentration and tHcy level in serum were measured by enzyme-linked immunosorbent assay. We found that allele T of rs1801133 in the MTHFR gene was associated with a significantly reduced risk of vitiligo (adjusted odds ratio 0·58, 95% confidence interval 0·43-0·76, P < 0·001). In addition, the patients with vitiligo had a lower activity concentration of MTHFR and higher level of tHcy than the controls. Correlation between these markers and the risk of vitiligo was also observed. Furthermore, the individuals with a no-risk genotype (CT + TT) of rs1801133 and higher activity concentration of MTHFR or lower level of tHcy had a significantly decreased risk of vitiligo. Our data suggest that MTHFR gene polymorphisms may play a vital role in genetic susceptibility to vitiligo. © 2014 British Association of Dermatologists.

  1. Methylenetetrahydrofolate reductase gene, homocysteine and coronary artery disease: the A1298C polymorphism does matter. Inferences from a case study (Madeira, Portugal).

    PubMed

    Freitas, Ana I; Mendonça, Isabel; Guerra, Graça; Brión, Maria; Reis, Roberto P; Carracedo, Angel; Brehm, António

    2008-01-01

    Elevated levels of plasma homocysteine, an independent risk factor and a strong predictor of mortality in patients with coronary artery disease (CAD), can result from nutritional deficiencies or genetic errors, including methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms. The contribution of these polymorphisms in the development of CAD remains controversial. We analysed the impact of MTHFR C677T and A1298C on fasting homocysteine and CAD in 298 CAD patients proved by angiography and 510 control subjects from the Island of Madeira (Portugal). After adjustment for other risk factors, plasma homocysteine remained independently correlated with CAD. Serum homocysteine was significantly higher in individuals with 677TT and 1298AA genotypes. There was no difference in the distribution of MTHFR677 genotypes between cases and controls but a significant increase in 1298AA prevalence was found in CAD patients. In spite of the clear effect of C677T mutation on elevated homocysteine levels we only found an association between 1298AA genotype and CAD in this population. The simultaneous presence of 677CT and 1298AA genotypes provides a significant risk of developing the disease, while the 1298AC genotype, combined with 677CC, shows a significant trend towards a decrease in CAD occurrence. The data shows an independent association between elevated levels of homocysteine and CAD. Both MTHFR polymorphisms are associated with increased fasting homocysteine (677TT and 1298AA genotypes), but only the 1298AA variant shows an increased prevalence in CAD group. Odds ratio seem to indicate that individuals with the MTHFR 1298AA genotype and the 677CT/1298AA compound genotype had a 1.6-fold increased risk for developing CAD suggesting a possible association of MTHFR polymorphisms with the risk of CAD in Madeira population.

  2. Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms resulting in suboptimal oocyte maturation: a discussion of folate status, neural tube defects, schizophrenia, and vasculopathy

    PubMed Central

    Jongbloet, Piet Hein; Verbeek, André LM; den Heijer, Martin; Roeleveld, Nel

    2008-01-01

    Several conditions apparent at birth, e.g., neural tube defects (NTDs) and cardiac anomalies, are associated with polymorphisms in folate-related genes, such as the 677C → T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene. Similar associations have been established for several constitutional chronic diseases in adulthood, such as schizophrenia, cardiovascular diseases, dementia, and even neoplasias in different organ systems. This spectrum of developmental anomalies and constitutional diseases may be linked to high-risk conceptions related to preovulatory overripeness ovopathy (PrOO). Some developmental anomalies, such as NTDs, are to a large extent prevented by supplementation of folic acid before conception, but supplementation does not seem to prevent cardiovascular disease or cognitive decline. These diverging results can be elucidated by introduction of the PrOO concept, as MTHFR polymorphisms and inherent low folate levels induce both non-optimal maturation of the oocyte and unsuccessful DNA methylation and demethylation, i.e. epigenetic mutations. The PrOO concept is testable and predicts in a random population the following: (1) female carriers of specific genetic MTHFR variants exhibit more ovulatory disturbances and inherent subfecundity traits, (2) descendents from a carrier mother, when compared with those from a wild-type mother, are more frequently conceived in PrOO high-risk conditions and, thus, (3) disadvantaged in life expectancy. If so, some MTHFR polymorphisms represent a novel, genetically determined, PrOO high-risk conception category comparable to those which are environmentally and behaviorly influenced. These high-risk conditions may cause developmental anomalies and defective epigenetic reprogramming in progeny. The interaction between genetic and environmental factors is a plausible mechanism of multifactorial inheritance. PMID:18616826

  3. Methylenetetrahydrofolate reductase C677T and methionine synthase A2756G gene polymorphisms and associated risk of cardiovascular diseases: A study from Jammu region.

    PubMed

    Raina, Jyotdeep K; Sharma, Minakashee; Panjaliya, Rakesh K; Bhagat, Minakshi; Sharma, Ravi; Bakaya, Ashok; Kumar, Parvinder

    2016-01-01

    Potent risk factors at both genetic and non-genetic levels are accountable for susceptibility and instigation of different cardiovascular phenotypes. Recently, homocysteine is being identified as an important predictor for cardiovascular diseases. Homocysteine remethylation plays a key role in the synthesis of methionine and S-adenosine methionine. Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MTR) genes are known to regulate the homocysteine remethylation reaction and higher homocysteine level is significantly associated with diverse cardiovascular phenotypes. In this context, we aimed to carry out a study on the association of MTHFR (C677T) and MTR (A2756G) gene polymorphism with CVD in population of Jammu region of J&K state. A total of 435 individuals were enrolled (195 CVD patients and 240 controls) for the case-control study. Genotyping of MTHFR C677T and MTR A2756G gene polymorphism was done by PCR-RFLP technique. Biochemical parameters were estimated by biochemical analyser. Metabolic variables such as serum LDL-C, TC and TG were significantly higher in patients (p<0.0001), whereas serum HDL-C was higher in controls. Majority of the patients were having history of hypertension (57.44%; p<0.0001) as a concomitant condition. The evaluation of genetic association showed that, MTHFR C6877T (OR: 8.89, 95% CI: 2.01-39.40) and MTR A2756G (OR: 1.48, 95% CI: 1.09-2.00) polymorphisms associated with higher risk of CVD. The present study reveals significant differences in nongenetic variables among patients and control as well as association of gene polymorphisms with CVD risk. Copyright © 2016. Published by Elsevier B.V.

  4. Ethnic variation of the C677T and A1298C polymorphisms in the methylenetetrahydrofolate-reductase (MTHFR) gene in southwestern Mexico.

    PubMed

    Antonio-Véjar, V; Del Moral-Hernández, O; Alarcón-Romero, L C; Flores-Alfaro, E; Leyva-Vázquez, M A; Hernández-Sotelo, D; Illades-Aguiar, B

    2014-09-29

    In this study, we examined the distribution of genotype and allele frequencies of the C677T and A1298C polymorphisms in the methylenetetrahydrofolate-reductase gene (MTHFR) in two ethnic groups in the State of Guerrero, Mexico, which were compared with those of the Mestizo population of the region. A comparative study was conducted on 455 women from two ethnic groups and a group of Mestizo women of the State of Guerrero, Mexico: 135 Nahuas, 124 Mixtecas, and 196 Mestizas. Genotyping of both polymorphisms were performed by using polymerase chain reaction-restriction fragment length polymorphism methods. We found that the 677TT genotype was more frequent in Nahua and Mixteca women compared to Mestiza women (P = 0.008), and the most prevalent genotype in both ethnic groups was the 1298AA genotype (P < 0.001). We also compared the 677T allele frequency obtained from the groups studied with the frequencies reported in other ethnic groups of Mexico (Huichol, Tarahumara, and Purepecha). There were significant differences between the three ethnic groups compared to Nahuas (Huicholes, P = 0.004; Tarahumaras, P < 0.001; Purepechas, P = 0.042). Our results indicated significant differences in the frequencies of the C677T and A1298C polymorphisms between the two ethnic groups and the Mestizo population of the State of Guerrero. In addition, we found strong differences with other ethnic groups in Mexico. These results could be useful for future studies investigating diseases related to folate metabolism, and could help the government to design specific nutrition programs for different ethnic groups.

  5. Meta- and Pooled Analyses of the Methylenetetrahydrofolate Reductase (MTHFR) C677T Polymorphism and Colorectal Cancer: A HuGE-GSEC Review

    PubMed Central

    Taioli, E.; Garza, M. A.; Ahn, Y. O.; Bishop, D. T.; Bost, J.; Budai, B.; Chen, K.; Gemignani, F.; Keku, T.; Lima, C. S. P.; Le Marchand, L.; Matsuo, K.; Moreno, V.; Plaschke, J.; Pufulete, M.; Thomas, S. B.; Toffoli, G.; Wolf, C. R.; Moore, C. G.; Little, J.

    2009-01-01

    Worldwide, over 1 million cases of colorectal cancer (CRC) were reported in 2002, with a 50% mortality rate, making CRC the second most common cancer in adults. Certain racial/ethnic populations continue to experience a disproportionate burden of CRC. A common polymorphism in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has been associated with a lower risk of CRC. The authors performed both a meta-analysis (29 studies; 11,936 cases, 18,714 controls) and a pooled analysis (14 studies; 5,068 cases, 7,876 controls) of the C677T MTHFR polymorphism and CRC, with stratification by racial/ethnic population and behavioral risk factors. There were few studies on different racial/ethnic populations. The overall meta-analysis odds ratio for CRC for persons with the TT genotype was 0.83 (95% confidence interval (CI): 0.77, 0.90). An inverse association was observed in whites (odds ratio = 0.83, 95% CI: 0.74, 0.94) and Asians (odds ratio = 0.80, 95% CI: 0.67, 0.96) but not in Latinos or blacks. Similar results were observed for Asians, Latinos, and blacks in the pooled analysis. The inverse association between the MTHFR 677TT polymorphism and CRC was not significantly modified by smoking status or body mass index; however, it was present in regular alcohol users only. The MTHFR 677TT polymorphism seems to be associated with a reduced risk of CRC, but this may not hold true for all populations. PMID:19846566

  6. Influence of methylenetetrahydrofolate reductase gene polymorphisms on the outcome of pediatric patients with non-Hodgkin lymphoma treated with high-dose methotrexate.

    PubMed

    D'Angelo, Velia; Ramaglia, Maria; Iannotta, Adriana; Francese, Matteo; Pota, Elvira; Affinita, Maria Carmen; Pecoraro, Giulia; Indolfi, Cristiana; Di Martino, Martina; Di Pinto, Daniela; Buffardi, Salvatore; Poggi, Vincenzo; Indolfi, Paolo; Casale, Fiorina

    2013-12-01

    High-dose methotrexate (MTX) is a key component of most treatment protocols for childhood and adolescent non-Hodgkin lymphoma (NHL). Recent studies have suggested that the toxicity of antifolate drugs, such as MTX, is affected by inherited single nucleotide polymorphisms (SNPs) in folate metabolizing genes. The aim of our study was to investigate the potential influence of the C677T and A1298C genetic variants of the methylenetetrahydrofolate reductase (MTHFR) gene on the clinical toxicity and efficacy of MTX in pediatric patients with NHL (n = 95) treated with therapeutic protocols Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) LNH-97 and EURO LB-02. We demonstrated that patients with the 677T genotype had an approximately six-fold greater risk of developing hematological toxicity compared with wild-type carriers, especially in the 1 g/m(2) treatment group (p = 0.01). Moreover, we identified a correlation between the risk of relapse and the T genotype: T carriers had reduced disease-free survival compared with wild-type patients (67% vs. 100%). Our data suggest a pharmacogenetic influence on the adverse effects of high-dose MTX in the 1 g/m(2) treatment group.

  7. Analysis of genetic polymorphisms of brain-derived neurotrophic factor and methylenetetrahydrofolate reductase in depressed patients in a Slovak (Caucasian) population.

    PubMed

    Evinova, Andrea; Babusikova, Eva; Straka, Stanislav; Ondrejka, Igor; Lehotsky, Jan

    2012-12-01

    Major depressive disorder (MDD) is a complex neuropsychiatric disorder where both gene-gene and gene-environment interactions play an important role, but the clues are still not fully understood. One carbon metabolism in the CNS plays a critical role in the synthesis and release of neurotransmitters which are relevant to depressive disorder. We studied genetic polymorphisms of the brain derived neurotrophic factor (BDNF) and the methylenetetrahydrofolate reductase (MTHFR) in association with major depressive disorder. We genotyped the BDNF G196A, the MTHFR C677T, and A1298C polymorphisms in 134 patients diagnosed with major depression and 143 control subjects in Slovak (Caucasian) cohort of patients and probands. We found no significant association of either the BDNF G196A or MTHFR C677T polymorphisms with major depressive disorder neither in female nor male group of patients. However, the MTHFR A1298C genotype distribution was 36.6% (for AA genotype), 48.5% (AC) and 14.9% (CC) for the depressed patients, and 48.9% (AA), 42.7% (AC) and 8.4% (CC), respectively, for the control subjects. Patients with MDD had a higher prevalence of the CC genotype (OR = 2.38; 95% CI = 1.07-5.32; p = 0.032) and the AC + CC genotype (OR = 1.67; 95% CI = 1.03-2.69; p = 0.037) in comparison with the control subjects. This study shows that CC genotype of the MTHFR A1298C is associated with higher risk of MDD in Slovak population.

  8. Association of Methylenetetrahydrofolate Reductase (MTHFR-677 and MTHFR-1298) Genetic Polymorphisms with Occlusive Artery Disease and Deep Venous Thrombosis in Macedonians

    PubMed Central

    Spiroski, Igor; Kedev, Sashko; Antov, Slobodan; Arsov, Todor; Krstevska, Marija; Dzhekova-Stojkova, Sloboda; Kostovska, Stojanka; Trajkov, Dejan; Petlichkovski, Aleksandar; Strezova, Ana; Efinska-Mladenovska, Olivija; Spiroski, Mirko

    2008-01-01

    Aim To analyze the association of methylenetetrahydrofolate reductase polymorphisms (MTHFR-677 and MTHFR-1298) with occlusive artery disease and deep venous thrombosis in Macedonians. Methods We examined 83 healthy respondents, 76 patients with occlusive artery disease, and 67 patients with deep venous thrombosis. Blood samples were collected and DNA was isolated from peripheral blood leukocytes. Identification of MTHFR mutations was done with CVD StripAssay (ViennaLab, Labordiagnostika GmbH, Vienna, Austria) and the population genetics analysis package, PyPop, was used for the analysis. Pearson P values, crude odds ratio, and Wald’s 95% confidence intervals were calculated. Results The frequency of C alleles of MTHFR-677 was 0.575 in patients with deep venous thrombosis, 0.612 in patients with occlusive artery disease, and 0.645 in healthy participants. The frequency of T allele of MTHFR-677 was lower in healthy participants (0.355) than in patients with occlusive artery disease (0.388) and deep venous thrombosis (0.425). The frequency of A allele for MTHFR-1298 was 0.729 in healthy participants, 0.770 in patients with occlusive artery disease, and 0.746 in patients with deep venous thrombosis. The frequency of C allele of MTHFR-1298 was 0.271 in healthy participants, 0.230 in patients with occlusive artery disease, and 0.425 in patients with deep venous thrombosis. No association of MTHFR-677 and MTHFR-1289 polymorphisms with occlusive artery disease and deep venous thrombosis was found, except for the protective effect of MTHFR/CA:CC diplotype for occlusive artery disease. Conclusion We could not confirm a significant association of MTHFR-677 and MTHFR-1289 polymorphisms with occlusive artery disease or deep venous thrombosis in Macedonians, except for the protective effect of MTHFR/CA:CC diplotype against occlusive artery disease. PMID:18293456

  9. Methylenetetrahydrofolate reductase C677T polymorphism and type 2 diabetes mellitus in Chinese population: a meta-analysis of 29 case-control studies.

    PubMed

    Zhu, Bo; Wu, Xiaomei; Zhi, Xueyuan; Liu, Lei; Zheng, Quanmei; Sun, Guifan

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR), a key enzyme in folate metabolism, had significant effects on the homocysteine levels. The common functional MTHFR C677T polymorphism had been extensively researched. Several studies had evaluated the relationship between MTHFR C677T polymorphism and type 2 diabetes mellitus (T2DM), but the results were still controversial in the Chinese Han population. This meta-analysis was conducted to evaluate the relationship between MTHFR C677T polymorphism and T2DM in the Chinese Han population. We searched the relevant studies in multiple electronic databases, which published up to December 2013. We reviewed and extracted data from all the included studies on the relationship between MTHFR C677T polymorphism and T2DM in the Chinese Han population. The odds ratios (ORs) and their 95% confidence intervals (95%CIs) were used to evaluate the relationship. Fixed-effects and random-effects meta-analysis were used to pool ORs by the heterogeneity. Publication bias and sensitivity analysis were also examined. 29 studies were finally included in our meta-analysis, which contained 4656 individuals with T2DM and 2127 healthy controls. There was a significant relationship between MTHFR C677T polymorphism and T2DM under dominant (OR: 1.70, 95% CI: 1.42-2.02), recessive (OR: 1.48, 95% CI: 1.21-1.80), homozygous (OR: 1.89, 95% CI: 1.47-2.42), heterozygous (OR: 1.58, 95% CI: 1.33-1.87), and additive (OR: 1.46, 95% CI: 1.28-1.68) genetic model in a random-effects model. Subgroup analysis also reached similar results. Sensitivity analysis indicated that the overall result were dependable. There was a significant relationship between MTHFR C677T polymorphism and T2DM in the Chinese Han population. The results of our meta-analysis suggested that MTHFR 677T allele might be a risk genetic factor of T2DM in the Chinese Han population.

  10. Methylenetetrahydrofolate Reductase C677T Polymorphism and Type 2 Diabetes Mellitus in Chinese Population: A Meta-Analysis of 29 Case-Control Studies

    PubMed Central

    Zhu, Bo; Wu, Xiaomei; Zhi, Xueyuan; Liu, Lei; Zheng, Quanmei; Sun, Guifan

    2014-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR), a key enzyme in folate metabolism, had significant effects on the homocysteine levels. The common functional MTHFR C677T polymorphism had been extensively researched. Several studies had evaluated the relationship between MTHFR C677T polymorphism and type 2 diabetes mellitus (T2DM), but the results were still controversial in the Chinese Han population. This meta-analysis was conducted to evaluate the relationship between MTHFR C677T polymorphism and T2DM in the Chinese Han population. Methods We searched the relevant studies in multiple electronic databases, which published up to December 2013. We reviewed and extracted data from all the included studies on the relationship between MTHFR C677T polymorphism and T2DM in the Chinese Han population. The odds ratios (ORs) and their 95% confidence intervals (95%CIs) were used to evaluate the relationship. Fixed-effects and random-effects meta-analysis were used to pool ORs by the heterogeneity. Publication bias and sensitivity analysis were also examined. Results 29 studies were finally included in our meta-analysis, which contained 4656 individuals with T2DM and 2127 healthy controls. There was a significant relationship between MTHFR C677T polymorphism and T2DM under dominant (OR: 1.70, 95% CI: 1.42–2.02), recessive (OR: 1.48, 95% CI: 1.21–1.80), homozygous (OR: 1.89, 95% CI: 1.47–2.42), heterozygous (OR: 1.58, 95% CI: 1.33–1.87), and additive (OR: 1.46, 95% CI: 1.28–1.68) genetic model in a random-effects model. Subgroup analysis also reached similar results. Sensitivity analysis indicated that the overall result were dependable. Conclusions There was a significant relationship between MTHFR C677T polymorphism and T2DM in the Chinese Han population. The results of our meta-analysis suggested that MTHFR 677T allele might be a risk genetic factor of T2DM in the Chinese Han population. PMID:25047451

  11. Impact of methylenetetrahydrofolate reductase polymorphisms and folate intake on the risk of gastric cancer and their association with Helicobacter pylori infection and tumor site.

    PubMed

    Chen, J; Yuan, L; Duan, Y Q; Jiang, J Q; Zhang, R; Huang, Z J; Xiao, X R

    2014-01-24

    Folic acid and methylenetetrahydrofolate reductase (MTHFR) may both affect the development of human cancer. We conducted a population-based case-control study in a Chinese population to investigate the potential role of folate intake and MTHFR gene polymorphisms in gastric cancer, and their interaction with infection by Helicobacter pylori and tumor location. A total of 767 patients with newly diagnosed gastric cancer and 775 controls were selected for this study. Genotyping of MTHFR C677T and A1298C was conducted by TaqMan assays using the ABI Prism 7911HT Sequence Detection System, and information on folate intake was collected by questionnaire. Compared with the CC genotype of MTHFR C677T, the TT genotype was significantly associated with a decreased risk of gastric cancer when the analysis was adjusted for other potential risk factors. We found a marginal significantly decreased risk of gastric cancer for individuals carrying the T allele [adjusted odds ratio (OR) = 0.83; 95% confidence interval (CI) = 0.65-1.01]. We detected an inverse relationship between folate intake and risk of gastric cancer, and the adjusted ORs (95%CI) for moderate and high folate intake were 0.97 (0.74-1.25) and 0.64 (0.49-0.87), respectively. Moreover, H. pylori infection, folate intake, and location of the tumor showed a significant interaction with the MTHFR C677T polymorphism. Our study suggests a protective role of MTHFR 677TT and high folate intake against gastric cancer, and the effect of the MTHFR C677T genotype may differ by H. pylori infection, folate consumption, and tumor site.

  12. Genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) in ethnic populations in Texas; a report of a novel MTHFR polymorphic site, G1793A.

    PubMed

    Rady, Peter L; Szucs, Sylvia; Grady, James; Hudnall, S David; Kellner, Leonard H; Nitowsky, Harold; Tyring, Stephen K; Matalon, Reuben K

    2002-01-15

    The importance of hyperhomocysteinemia, birth defects, and vascular diseases has been the subject of intense investigations. The polymorphic MTHFR mutations (C677T and A1298C) cause mild hyperhomocysteinemia, especially in homozygotes for C677T, but also in compound heterozygotes for C677T/A1298C. The subject of this report is the frequency of the polymorphic mutations in the MTHFR gene C677T, C1298A, and newly discovered mutation G1793A, as well as the association with MTRR polymorphic site A66G in different ethnic groups. Four ethnic groups were studied: African-Americans, Caucasians, Hispanics, and Ashkenazi Jews. There are statistically significant differences in the frequency of these alleles in the different populations studied, which impacts compound heterozygosity for such alleles in these populations. DNA samples obtained from the blood of healthy individuals of African-Americans, Hispanics, and Caucasians from south Texas were analyzed and compared to those obtained from Ashkenazi Jewish individuals. The polymorphic site, the G1793A allele, is least frequent among Ashkenazi individuals, 1.3%, compared to 6.9% among Caucasians (P = 0.001), 5.8% among Hispanics (P = 0.012), and 3.1% among African-Americans. The MTRR polymorphic site shows the lowest allele frequency among Hispanics, 28.6%, compared to 34% among African-Americans, 43.1% among Ashkenazi Jews (P = 0.002), and 54.4% among Caucasians (P < 0.0001). Statistically significant differences in allele frequencies of C677T and C1298A polymorphisms were also observed in these populations. Compound heterozygosity for multiple polymorphic alleles may play a role in birth defects and vascular diseases. Copyright 2001 Wiley-Liss, Inc.

  13. B-vitamins, methylenetetrahydrofolate reductase (MTHFR) and hypertension.

    PubMed

    Ward, Mary; Wilson, Carol P; Strain, J J; Horigan, Geraldine; Scott, John M; McNulty, Helene

    2011-07-01

    Hypertension is a leading risk factor for cardiovascular disease (CVD) and stroke. A common polymorphism in the gene encoding the enzyme methylenetetrahydrofolate reductase (MTHFR), previously identified as the main genetic determinant of elevated homocysteine concentration and also recognized as a risk factor for CVD, appears to be independently associated with hypertension. The B-vitamin riboflavin is required as a cofactor by MTHFR and recent evidence suggests it may have a role in modulating blood pressure, specifically in those with the homozygous mutant MTHFR 677 TT genotype. If studies confirm that this genetic predisposition to hypertension is correctable by low-dose riboflavin, the findings could have important implications for the management of hypertension given that the frequency of this polymorphism ranges from 3 to 32 % worldwide.

  14. Primary thrombophilia in Mexico. II. Factor V G1691A (Leiden), prothrombin G20210A, and methylenetetrahydrofolate reductase C677T polymorphism in thrombophilic Mexican mestizos.

    PubMed

    Ruiz-Argüelles, G J; Garcés-Eisele, J; Reyes-Núñez, V; Ramírez-Cisneros, F J

    2001-01-01

    We have shown that in Mexican mestizo patients with clinical features of primary thrombophilia, 39% have activated protein C resistance phenotype, 5% protein C deficiency, and 2% protein S deficiency. In the present study, in a group of 37 thrombophilic Mexicans and 50 normal controls, we assessed the factor V G1691A (Leiden), the prothrombin G20210A, and the methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphisms. Four patients were found to be heterozygous for factor V Leiden, 5 heterozygous for the prothrombin 20210, 16 heterozygous, and 6 homozygous for the MTHFR 677. There were four individuals with co-segregation of alleles: two heterozygotes for the factor V Leiden/prothrombin 20210, one heterozygote for prothrombin 20210/MTHFR 677, and one heterozygote for prothrombin 20210/homozygote for MTHFR 677. For factor V Leiden, prothrombin 20210, and MTHFR 677 mutations, the allele frequencies were respectively 1% (+/-0.2%, alpha = 0.05), <1% and 51% (+/-5%, alpha = 0.05), with calculated relative risks for thrombosis of 5.94 (P = 0.08), >7.66 (P < 0.05), and 0.44 (P NS), respectively. In Mexican mestizo thrombophilic patients, the low prevalence of the factor V Leiden mutation (10.8%) and the high prevalence of the prothrombin 20210 mutation (13.5%) contrast with those identified in Caucasian thrombophilic patients (21% and 6%, respectively; P < 0.01). On the other hand, the high prevalence of the MTHFR 677 mutation gene both in normal controls (78%) and thrombophilic patients (61%) does not support a role of this mutation in the thrombogenesis of Mexican mestizo patients.

  15. The effects of polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and methionine synthase reductase (MTRR) on the risk of cervical intraepithelial neoplasia and cervical cancer in Korean women.

    PubMed

    Tong, Seo-Yun; Lee, Jong-Min; Song, Eun-Seop; Lee, Kwang-Beom; Kim, Mi-Kyung; Yun, Young Mi; Lee, Jae-Kwan; Son, Sung-Kyong; Lee, Jung-Pil; Kim, Jae-Hoon; Hur, Soo-Young; Kwon, Yong-Il

    2010-01-01

    The purpose of the study was to investigate the association between cervical cancer risk and single-nucleotide polymorphisms (SNPs) in three one-carbon metabolism genes, methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and methionine synthase reductase (MTRR) in Korean women. Twelve SNPs were identified in MTHFR, MTR, and MTRR in the 927 case-control samples, which included 165 cervical intraepithelial neoplasia 1 (CIN1), 167 cervical intraepithelial neoplasia 2 and 3 (CIN2/3), 155 cervical cancer patients, and 440 normal controls. The frequencies of the genotypes and haplotypes were assessed in the controls, CINs, and cervical cancers. Individual carriers of the variant allele C of MTHFR A1298C (rs1801131) had a 0.64-fold [95% confidence interval (CI): 0.42-0.98] decreased risk for CIN2/3 compared with common homozygotes. However, no significant association was found between most other variants and cervical cancer risk. The results also identified an increased CIN1 risk in carriers with at least one copy of haplotype 3 in the MTHFR gene (odds ratio, 1.88; 95% CI: 1.03-3.42). In conclusion, there was no significant association between most SNPs in MTHFR, MTR, or MTRR and the risk of CIN and cervical cancer in Korean women. In addition, there was no significant association of MTHFR haplotypes with risk of CIN2/3 and cervical cancer.

  16. Methylenetetrahydrofolate reductase (MTHFR) 677C>T and methionine synthase reductase (MTRR) 66A>G polymorphisms: association with serum homocysteine and angiographic coronary artery disease in the era of flour products fortified with folic acid.

    PubMed

    Brilakis, Emmanouil S; Berger, Peter B; Ballman, Karla V; Rozen, Rima

    2003-06-01

    We analyzed the association between the methylenetetrahydrofolate reductase (MTHFR) 677C>T and methionine synthase reductase (MTRR) 66A>G polymorphisms with serum homocysteine and with coronary artery disease (CAD) in 504 patients undergoing clinically-indicated angiography between July 1998 and January 1999. Significant CAD (>/=50% stenosis in >/=one artery, blinded to risk factors) was present in 271 patients (54%). Median homocysteine (micromol/l) was 8.8 (interquartile range: 7.5-10.7). The prevalence of the MTHFR TT, CT, and CC genotypes was 11, 44 and 45%, respectively. Median tHcy (with interquartile ranges) for the entire population was 8.8 (7.5-10.7), and for the TT, CT, and CC genotypes was 9.7 (8.2-11.4), 8.8 (7.5-10.7), and 8.6 (7.3-10.6) micromol/l, respectively (P=0.04). On multiple logistic regression analysis, the MTHFR TT genotype was associated with hyperhomocysteinemia (adjusted OR=3.57; 95% CI, 1.47-8.70), but not with significant CAD. The prevalence of the MTRR AA, AG, GG genotypes was 19, 50 and 31%, respectively. There were no differences in mean homocysteine, prevalence of hyperhomocysteinemia and significant CAD between the three genotypes. On multivariate analysis, the MTRR genotypes were not associated with serum homocysteine or with significant CAD.

  17. Relationship of the 1793G-A and 677C-T polymorphisms of the 5,10-methylenetetrahydrofolate reductase gene to coronary artery disease.

    PubMed

    Kebert, Cory B; Eichner, June E; Moore, William E; Schechter, Eliot; Yaoi, Takuro; Vogel, Steve; Allen, Richard A; Dunn, S Terence

    2006-01-01

    Numerous studies have investigated the relationship between polymorphisms, in particular 677C-T and 1298A-C, of the methylene-tetrahydrofolate reductase (MTHFR) gene and coronary artery disease (CAD) with conflicting results. This study investigates the potential association of two point mutations in MTHFR, 677C-T and 1793G-A, along with other risk factors, with CAD. This is the first hospital-based study to investigate 1793G-A in this context. Genotype analysis was performed on 729 Caucasians and 66 African Americans undergoing coronary angiography using a novel PCR-based assay involving formation of Holliday junctions. Allelic frequencies for 677C-T were 66.2% C and 33.8% T for Caucasians and 90.9% C and 9.1% T for African Americans. With respect to the 1793G-A polymorphism, allelic frequencies were 94.7% G and 5.3% A for Caucasians and 99.2% G and 0.8% A for African Americans. Disease associations were examined in the Caucasian patients due to their greater genotype variability and larger number in the patient cohort. Results suggest that neither 677CT heterozygotes (OR-1.36; 95% CI 0.95 to 1.96) nor mutant homozygotes (OR-0.73; 95% CI 0.44 to 1.20) have either an increased or decreased risk for CAD compared to the 677CC genotype. Likewise, the 1793GA genotype did not demonstrate a statistically significant association with CAD compared to 1793GG patients (OR-0.79; 95% CI 0.47 to 1.33). Mean homocysteine levels (mumol/L) increased from normal to mutant for 677C-T (677CC: 10.2; 677CT: 11.0; 677TT: 11.6) and normal to heterozygous in 1793G-A (1793GG: 10.7; 1793GA: 11.5). These MTHFR polymorphisms did not contribute to the prediction of clinically defined CAD in Caucasians.

  18. Relationship of the 1793G-A and 677C-T Polymorphisms of the 5,10-Methylenetetrahydrofolate Reductase Gene to Coronary Artery Disease

    PubMed Central

    Kebert, Cory B.; Eichner, June E.; Moore, William E.; Schechter, Eliot; Yaoi, Takuro; Vogel, Steve; Allen, Richard A.; Dunn, S. Terence

    2006-01-01

    Numerous studies have investigated the relationship between polymorphisms, in particular 677C-T and 1298A-C, of the methylene-tetrahydrofolate reductase (MTHFR) gene and coronary artery disease (CAD) with conflicting results. This study investigates the potential association of two point mutations in MTHFR, 677C-T and 1793G-A, along with other risk factors, with CAD. This is the first hospital-based study to investigate 1793G-A in this context. Genotype analysis was performed on 729 Caucasians and 66 African Americans undergoing coronary angiography using a novel PCR-based assay involving formation of Holliday junctions. Allelic frequencies for 677C-T were 66.2% C and 33.8% T for Caucasians and 90.9% C and 9.1% T for African Americans. With respect to the 1793G-A polymorphism, allelic frequencies were 94.7% G and 5.3% A for Caucasians and 99.2% G and 0.8% A for African Americans. Disease associations were examined in the Caucasian patients due to their greater genotype variability and larger number in the patient cohort. Results suggest that neither 677CT heterozygotes (OR-1.36; 95% CI 0.95 to 1.96) nor mutant homozygotes (OR-0.73; 95% CI 0.44 to 1.20) have either an increased or decreased risk for CAD compared to the 677CC genotype. Likewise, the 1793GA genotype did not demonstrate a statistically significant association with CAD compared to 1793GG patients (OR-0.79; 95% CI 0.47 to 1.33). Mean homocysteine levels (μmol/L) increased from normal to mutant for 677C-T (677CC: 10.2; 677CT: 11.0; 677TT: 11.6) and normal to heterozygous in 1793G-A (1793GG: 10.7; 1793GA: 11.5). These MTHFR polymorphisms did not contribute to the prediction of clinically defined CAD in Caucasians. PMID:17264399

  19. Association of methylenetetrahydrofolate reductase C677T polymorphism and serum lipid levels in the Guangxi Bai Ku Yao and Han populations

    PubMed Central

    2010-01-01

    Background The association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphism and serum lipid profiles is still controversial in diverse ethnics. Bai Ku Yao is an isolated subgroup of the Yao minority in China. The aim of the present study was to eveluate the association of MTHFR C677T polymorphism and several environmental factors with serum lipid levels in the Guangxi Bai Ku Yao and Han populations. Methods A total of 780 subjects of Bai Ku Yao and 686 participants of Han Chinese were randomly selected from our previous stratified randomized cluster samples. Genotyping of the MTHFR C677T was performed by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. Results The levels of serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein (Apo) AI and ApoB were lower in Bai Ku Yao than in Han (P < 0.05-0.001). The frequency of C and T alleles was 77.4% and 22.6% in Bai Ku Yao, and 60.9% and 39.1% in Han (P < 0.001); respectively. The frequency of CC, CT and TT genotypes was 58.7%, 37.3% and 4.0% in Bai Ku Yao, and 32.6%, 56.4% and 11.0% in Han (P < 0.001); respectively. The levels of TC and LDL-C in both ethnic groups were significant differences among the three genotypes (P < 0.05-0.01). The T allele carriers had higher serum TC and LDL-C levels than the T allele noncarriers. The levels of ApoB in Han were significant differences among the three genotypes (P < 0.05). The T allele carriers had higher serum ApoB levels as compared with the T allele noncarriers. The levels of TC, TG and LDL-C in Bai Ku Yao were correlated with genotypes (P < 0.05-0.001), whereas the levels of LDL-C in Han were associated with genotypes (P < 0.001). Serum lipid parameters were also correlated with sex, age, body mass index, alcohol consumption, cigarette smoking, and blood pressure in the both ethnic

  20. Effects of Maternal 5,10-Methylenetetrahydrofolate Reductase C677T and A1298C Polymorphisms and Tobacco Smoking on Infant Birth Weight in a Japanese Population

    PubMed Central

    Yila, Thamar Ayo; Sasaki, Seiko; Miyashita, Chihiro; Braimoh, Titilola Serifat; Kashino, Ikuko; Kobayashi, Sumitaka; Okada, Emiko; Baba, Toshiaki; Yoshioka, Eiji; Minakami, Hisanori; Endo, Toshiaki; Sengoku, Kazuo; Kishi, Reiko

    2012-01-01

    Background Intracellular folate hemostasis depends on the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene. Because 5,10-MTHFR 677TT homozygosity and tobacco smoking are associated with low folate status, we tested the hypothesis that smoking in mothers with 5,10-MTHFR C677T or A1298C polymorphisms would be independently associated with lower birth weight among their offspring. Methods We assessed 1784 native Japanese mother-child pairs drawn from the ongoing birth cohort of The Hokkaido Study on Environment and Children’s Health. Data (demographic information, hospital birth records, and biological specimens) were extracted from recruitments that took place during the period from February 2003 to March 2006. Maternal serum folate were assayed by chemiluminescent immunoassay, and genotyping of 5,10-MTHFR C677T/A1298C polymorphisms was done using a TaqMan allelic discrimination assay. Results The prevalence of folate deficiency (<6.8 nmol/L) was 0.3%. The 5,10-MTHFR 677CT genotype was independently associated with an increase of 36.40 g (95% CI: 2.60 to 70.30, P = 0.035) in mean infant birth weight and an increase of 90.70 g (95% CI: 6.00 to 175.50, P = 0.036) among male infants of nonsmokers. Female infants of 677TT homozygous passive smokers were 99.00 g (95% CI: −190.26 to −7.56, P = 0.034) lighter. The birth weight of the offspring of smokers with 5,10-MTHFR 1298AA homozygosity was lower by 107.00 g (95% CI: −180.00 to −33.90, P = 0.004). Conclusions The results suggest that, in this population, maternal 5,10-MTHFR C677T polymorphism, but not the 5,10-MTHFR A1298C variant, is independently associated with improvement in infant birth weight, especially among nonsmokers. However, 5,10-MTHFR 1298AA might be associated with folate impairment and could interact with tobacco smoke to further decrease birth weight. PMID:22277790

  1. Association of methylenetetrahydrofolate reductase (MTHFR 677C>T) and thymidylate synthase (TSER and TS 1494del6) polymorphisms with premature ovarian failure in Korean women.

    PubMed

    Rah, HyungChul; Jeon, Young Joo; Choi, Youngsok; Shim, Sung Han; Yoon, Tae Ki; Choi, Dong Hee; Cha, Sun Hee; Kim, Nam Keun

    2012-11-01

    The aim of our study was to investigate whether methylenetetrahydrofolate reductase (MTHFR) gene variant (MTHFR 677C>T) and thymidylate synthase (TS) gene variants (TS enhancer region [TSER] and TS 1494del6) confer a risk for premature ovarian failure (POF). We genotyped 136 POF patients and 236 controls among Korean women for the three single nucleotide polymorphism sites using polymerase chain reaction restriction fragment length polymorphism analysis. Differences in the MTHFR 677C>T, TSER, and TS 1494del6 genotype frequencies between POF patients and controls were compared, and odds ratios (ORs) and 95% CIs were determined as a measure of the strength of the association between genotypes and POF. The MTHFR 677CT and CT + TT variant genotypes were more frequent in POF patients than in controls (OR, 2.249; 95% CI, 1.317-3.843; and OR, 2.132; 95% CI, 1.268-3.585, respectively). The combined genotype frequencies of MTHFR 677CT + TT/TSER 3R3R and 677CT + TT/TS 1494del6 del6/del6 were higher in patients than in controls (OR, 2.300; 95% CI, 1.219-4.337; and OR, 3.314; 95% CI, 1.623-6.767, respectively). The T-3R-del6 and T-2R-del6 (MTHFR 677C>T/TSER/TS 1494del6) haplotypes were more frequent in patients (OR, 1.450; 95% CI, 1.050-2.002; and OR, 2.911; 95% CI, 1.191-7.117, respectively), whereas the C-2R-del6 haplotype was less frequent in patients (OR, 0.372; 95% CI, 0.152-0.912). The T-del6 (MTHFR 677/TS 1494del6) haplotype frequency was higher among patients (OR, 1.653; 95% CI, 1.206-2.266), whereas the C-del6 haplotype frequency was lower among patients (OR, 0.700; 95% CI, 0.516-0.950). We did not find an association between TSER or TS 1494del6 polymorphisms and POF. Our data suggest that the MTHFR 677T allele may increase the risk for POF, which could lead to the development of novel genetic markers for predicting the risk of POF in patients.

  2. Genetic susceptibility of methylenetetrahydrofolate reductase (MTHFR) gene C677T, A1298C, and G1793A polymorphisms with risk for bladder transitional cell carcinoma in men.

    PubMed

    Safarinejad, Mohammad Reza; Shafiei, Nayyer; Safarinejad, Shiva

    2011-12-01

    We performed a case-control study of 158 bladder transitional cell carcinoma (TCC) cases and 316 controls to investigate the association between methylenetetrahydrofolate reductase (MTHFR) C677T, A1298G, and G1793A polymorphisms and bladder cancer susceptibility by polymerase chain reaction restriction fragment length polymorphism (PCR-RLFP) technique. The controls were frequency-matched to the cases by age (± 5 years), ethnicity, and smoking status. We also measured serum levels of total homocysteine (tHcy), folate, and vitamin B12. It was found that the 1298AC (odds ratio, OR = 3.74; 95% confidence interval, CI = 2.34-5.47; P = 0.001) and 1298CC (OR = 3.46, 95% CI = 2.37-5.52; P = 0.001) genotypes of MTHFR A1298C were significantly associated with increased risk of bladder TCC. The MTHFR C677T and G1793A polymorphisms were not associated with bladder TCC. After stratification for grade and stage, we observed that the 677TT (OR = 4.47, 95% CI = 2.74-6.72; P = 0.001) and MTHFR 1298CC (OR = 4.78, 95% CI = 2.82-6.89; P = 0.001) genotypes of MTHFR were associated with increased risk of muscle-invasive bladder TCC. We also found that the MTHFR 677CT+1298AA genotypes were associated with an approximately 70% reduction in risk of bladder cancer (OR = 0.31; 95% CI = 0.15-0.68) compared to the combined referent genotype. There were 8 haplotypes and 16 haplotype genotypes based on these three variants. When we used the haplotypes and assumed that the 677T, 1298C, and 1793G alleles were risk alleles, the adjusted odds ratios increased as the number of risk alleles increased: 1.00 for 0-1 variant, 1.88 (1.4-2.7) for any two risk alleles and 2.07 (1.6-2.8) for any three risk alleles. Serum tHcy levels were significantly higher in carriers of the 677T, 1298C, and 1793G alleles compared to noncarriers (all P < 0.01). There was no significant correlation between serum levels of tHcy and folate and bladder cancer risk. Further studies in larger samples size and different

  3. Association between the methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism and ischemic stroke in the Chinese population: a meta-analysis.

    PubMed

    Zhu, Xiao-Yan; Hou, Rong-Yao; Pan, Xu-Dong; Wang, Yu-Chun; Zhang, Zheng-Shou; Guo, Rui-You

    2015-01-01

    The association between the methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism and ischemic stroke (IS) has been extensively studied; however, the results from genetic association studies have been inconsistent even in the Chinese population. As far as we know, there was no previous meta-analysis concerning this association in the Chinese population. Therefore, the aim of our meta-analysis was to further evaluate the association in the Chinese population. We collected all of the relevant studies from Pubmed, OVID, Embase, Chinese Wan Fang database, CNKI, Chongqing VIP database and CBM up to August 2014. The available data was analyzed by Stata (version 12.0). We used odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to present the strength of the association. Heterogeneity was evaluated by the Q-test and I(2) statistic. Different genetic models, subgroup analysis, publication bias and sensitivity analysis were used to improve the comprehensive understanding. The results showed a significant association between the MTHFR gene C677T polymorphism and IS in six genetic models (additive model: OR = 1.34, 95%CI: 1.17 ∼ 1.54, p < 0.001; dominant model: OR = 1.44, 95% CI:1.26 ∼ 1.64, p < 0.001; recessive model: OR = 1.45, 95% CI: 1.15 ∼ 1.83, p = 0.001; heterozygote model: OR = 1.35, 95% CI: 1.18 ∼ 1.55, p < 0.001; homozygote model: OR = 1.80, 95% CI: 1.34 ∼ 2.41, p < 0.001; and allelic model: OR = 1.34, 95% CI: 1.17 ∼ 1.53, p < 0.001) based on the overall population, as well as subgroup analysis. In addition, the similar results were obtained in the sensitivity analysis based on studies with the high quality. This meta-analysis presented a significant association between the MTHFR gene C677T polymorphism and IS, the T allele might be a risk factor for IS in the Chinese population.

  4. Pregnancy-associated osteoporosis with a heterozygous deactivating LDL receptor-related protein 5 (LRP5) mutation and a homozygous methylenetetrahydrofolate reductase (MTHFR) polymorphism.

    PubMed

    Cook, Fiona J; Mumm, Steven; Whyte, Michael P; Wenkert, Deborah

    2014-04-01

    Pregnancy-associated osteoporosis (PAO) is a rare, idiopathic disorder that usually presents with vertebral compression fractures (VCFs) within 6 months of a first pregnancy and delivery. Spontaneous improvement is typical. There is no known genetic basis for PAO. A 26-year-old primagravida with a neonatal history of unilateral blindness attributable to hyperplastic primary vitreous sustained postpartum VCFs consistent with PAO. Her low bone mineral density (BMD) seemed to respond to vitamin D and calcium therapy, with no fractures after her next successful pregnancy. Investigation of subsequent fetal losses revealed homozygosity for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism associated both with fetal loss and with osteoporosis (OP). Because her neonatal unilateral blindness and OP were suggestive of loss-of-function mutation(s) in the gene that encodes LDL receptor-related protein 5 (LRP5), LRP5 exon and splice site sequencing was also performed. This revealed a unique heterozygous 12-bp deletion in exon 21 (c.4454_4465del, p.1485_1488del SSSS) in the patient, her mother and sons, but not her father or brother. Her mother had a normal BMD, no history of fractures, PAO, ophthalmopathy, or fetal loss. Her two sons had no ophthalmopathy and no skeletal issues. Her osteoporotic father (with a family history of blindness) and brother had low BMDs first documented at ages ∼40 and 32 years, respectively. Serum biochemical and bone turnover studies were unremarkable in all subjects. We postulate that our patient's heterozygous LRP5 mutation together with her homozygous MTHFR polymorphism likely predisposed her to low peak BMD. However, OP did not cosegregate in her family with the LRP5 mutation, the homozygous MTHFR polymorphism, or even the combination of the two, implicating additional genetic or nongenetic factors in her PAO. Nevertheless, exploration for potential genetic contributions to PAO may explain part of the pathogenesis of this

  5. Impact of Genetic Polymorphism of methylenetetrahydrofolate reductase C677T on Development of Hyperhomocysteinemia and Related Oxidative Changes in Egyptian β-Thalassemia Major Patients

    PubMed Central

    Abd-Elmawla, Mai A.; Rizk, Sherine M.; Youssry, Ilham; Shaheen, Amira A.

    2016-01-01

    Background β-thalasemia major (β-TM) patients often suffer from various vascular complications together with increased oxidative stress. Hyperhomocysteinemia (Hhcy) has been defined as a risk factor for these complications. Genetic polymorphism of methylenetetrahydrofolate reductase (MTHFR) C677T has been shown to cause Hhcy particularly in individuals with low B-vitamins. However, the status of homocysteine (hcy) in β-TM has not yet been adequately defined. Aim To evaluate the genetic polymorphism of MTHFR C677T among β-TM patients and its prospective contribution to Hhcy and related oxidative changes. Subjects and Methods Genotyping for MTHFR C677T was done by PCR-RFLP technique. Plasma hcy, vitamin B12, folate, malondialdehyde (MDA), total antioxidant capacity (TAC), oxidized low density lipoprotein (oxLDL), total nitric oxide (NOx) and lipid profile were determined in 66 β-TM patients and 66 control subjects of matched age and sex. Results The prevalence of MTHFR 677TT genotype was significant among β-TM patients (12%) compared to (3%) controls (OR = 4.9, 95%CI:1.2–24.2,P = 0.03). A strong association between Hhcy and MTHFR TT genotype was observed (OR = 7.7, 95%CI:2.8–20.9) where all β-TM patients with TT genotype were hyperhomocystienemic (≥ 15 μmol/l) and having sub-optimal folate level than those with CT or CC genotypes. Hyperhomocystienemic patients have suffered from increased oxidative stress characterized by significant increase in plasma MDA and oxLDL, and a significant reduction of plasma TAC and total NOx. Lipid profile of those patients was severely affected indicated by reduction in HDL and HDL/LDL and elevation in atherogenic index as compared with CC genotype. Other measured parameters were not significantly different among β-TM patients with different MTHFR genotypes. Conclusion This study suggests that Egyptian β-TM patients with MTHFR 677TT genotype could be at increasing risk of developing Hhcy particularly with folate

  6. Polymorphisms in methylenetetrahydrofolate reductase and cystathionine beta-synthase in oral cancer - a case-control study in southeastern Brazilians.

    PubMed

    Barbosa, Andressa; Dos Santos, Marcelo; de Podestá, José Roberto Vasconcelos; Gouvêa, Sônia Alves; Von Zeidler, Sandra Ventorin; Louro, Iúri Drumond; Cordeiro-Silva, Melissa de Freitas

    2016-01-01

    Oral squamous cell carcinoma (OSCC) is a serious public health problem, due to its high mortality rate and worldwide rising incidence. OSCC susceptibility is mediated by interactions between genetic and environmental factors. Studies suggest that genetic variants encoding enzymes involved in folate metabolism may modulate OSCC risk by altering DNA synthesis/repair and methylation process. The goals of this study were to evaluate the association of three genotypic polymorphism (MTHFR C677T, MTHFR A1298C and CBS 844ins68) and oral cancer risk in southeastern Brazilians and evaluate the interactions between polymorphisms and clinical histopathological parameters. This case-control study included 101 cases and 102 controls in the state of Espírito Santo, Brazil. MTHFR genotyping was done by PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism) and CBS genotyping by PCR (polymerase chain reaction) analysis. MTHFR C677T polymorphism was associated with lymph node involvement. Genotype CT+TT acted as a protective factor. MTHFR A1298C AC+CC genotype was associated with tumor differentiation, and possibly with a better prognosis. In risk analysis, no correlation was observed between genotypes and OSCC. We concluded that MTHFR C677T, MTHFR A1298C and CBS 844ins68 polymorphisms were not associated with OSCC risk in southeastern Brazilians; however, we suggest a prognosis effect associated with MTHFR C677T and A1298C polymorphisms in OSCC. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  7. Genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene and susceptibility to depression in Asian population: a systematic meta-analysis.

    PubMed

    Rai, V

    2014-01-01

    Genetic association studies on MTHFR C677 T polymorphism and depression have been repeatedly performed over the last two decades and results are generally inconsistent. The aim of the present study was to assess the risk of MTHFR C677T polymorphism for depression in Asian population. The author performed a meta-analysis and pooled data from individual case-control studies that examined the association between C677T polymorphism and depression (meta-analysis: 13 studies, 1,120 cases and 1,688 controls).The pooled Odd Ratios (OR) were estimated by both fixed effects and random effects models. Overall, there was an association between MTHFR C677T polymorphism and increased risk of depression under five genetic models (OR T vs. C=1.44, 95% CI= 1.56-1.78, P=0.001; OR TT vs. CC= 1.78, 95% CI 1.17– 2.69, P=0.006; OR CT vs CC=1.102, 95% CI=0.91-1.32,P=0.31; OR TT vs. CT+CC=1.73, 95% CI= 0.87-3.41, P=0.11; OR TT+CT vs. CC=1.26, 95% CI=0.96-1.64, P=0.08). Sensitivity analysis suggested exclusion of any single study did not alter the overall pooled Ors. In conclusion results of present meta-analysis supports that there is a significant association between MTHFR C677T polymorphism and depression risk, and MTHFR 677T allele contributes to increased risk of depression in Asian individuals.

  8. Comparison of the frequency of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in depressed versus nondepressed patients.

    PubMed

    Lizer, Mitsi H; Bogdan, Renee L; Kidd, Robert S

    2011-11-01

    Numerous studies have found an association between low serum folate levels and incidence of depression. Folic acid supplementation has been successfully used as an adjunct to treat depression in these patients. However, some individuals have a genetic deficiency in the methylene tetrahydrofolate reductase (MTHFR) gene that limits conversion of folic acid to its biologically active form, L-methylfolate. Several studies have identified a higher frequency of genetic variations in the MTHFR gene in depressed patients than in nondepressed controls. This study evaluated the frequency of the most common genetic variation MTHFR C667T in a group of depressed U.S. Caucasians and compared results with those of a control group of nondepressed U.S. Caucasians. Subjects were recruited from a psychiatric practice, an ambulatory care clinic, and the community. Informed consent and a cheek swab sample were obtained from each subject for analysis using real-time polymerase chain reaction (PCR). Allele and genotype frequencies were compared using Pearson X2 analysis. Complete data were obtained for 156 subjects. No significant differences were found in frequency of the MTHFR C667T T allele (0.415 vs 0.365; p=0.408) or the MTHFR C667T TT genotype (20.7% vs 17.6%; p=0.619) between the depressed and non-depressed controls, respectively. Therefore, use of L-methylfolate without an additional indication of need does not appear to be warranted in this group of U.S. Caucasians. Some patients may benefit from L-methylfolate, but an evidence-based approach, such as MTHFR genotyping, should be used to identify these specific patients. Additional research is also needed to confirm the benefit of L-methylfolate in specific patient populations (e.g., MTHFR TT genotype).

  9. [Investigation of detoxification polymorphisms genes, methylenetetrahydrofolate-reductase (MTHFR) and P53 in the radiosensitive human cells].

    PubMed

    Shagirova, Zh M; Ushenkova, L N; Mikhaĭlov, V F; Kurbatova, L A; Kuz'mina, N S; Semiachkina, A N; Vasil'eva, I M; Mazurik, V K; Zasukhina, G D

    2010-01-01

    The genes of detoxication, MTHFR and p53 were studied in Down' and Ehlers-Danlos syndrome cells. The frequency GSTM1(0/0) genotype in Down syndrome patients was in 1.5 times higher than in control cells (p < 0.069). Opposite the frequency GSTM1(0/0) genotype in Ehlers-Danlos syndrome was 23.3% 2 times lower than in control cells (p < 0.034). This indication was in 2 times lower in women cells than in men cells and in 3 times lower than in control cells (p < 0.026). The mutations of p53 gene (7th exon) were detected in 4 from 11 Down patients (36.7%; in 2 cases af women and men), in Ehlers-Danlos patients--in 5 cases and only in men (29.4% among all the observed patients). The observations 24 healthy donors weren't revealed any mutations (p < 0.013-0.001). The hypothesis about the connection between gene polymorphisms which take a part in genome stability and radiosensitivity in Down and Ehlers-Danlos patients was developed.

  10. The Impact of Methylenetetrahydrofolate Reductase C677T Polymorphism on Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplantation with Methotrexate Prophylaxis

    PubMed Central

    Shin, Dong-Yeop; Koh, Youngil; Yoon, Sung-Soo; Seong, Moon-Woo; Park, Sung Sup; Kim, Jin Hee; Lee, Yun-Gyoo; Kim, Inho

    2016-01-01

    Pharmacogenomics can explain the inter-individual differences in response to drugs, including methotrexate (MTX) used for acute graft-versus-host disease (aGVHD) prophylaxis during hematopoietic stem cell transplantation (HSCT). In real-world practice, preplanned MTX dose is arbitrarily modified according to observed toxicity which can lead to unexpected and severe aGVHD development. We aimed to validate the influence of MTHFR C677T polymorphism on the outcomes of allogenic HSCT in a relatively under-represented homogenous Asian population. A total of 177 patients were divided into 677TT group versus 677C-carriers (677CT+677CC), and clinical outcomes along with baseline characteristics were analyzed and compared. Although there was a tendency towards increased peak liver function test results and accordingly greater delta values between the highest and the baseline in 677TT group, we found no associations between genotypes and hepatotoxicity. However, the incidence of acute liver GVHD (≥ grade 2) was significantly higher in the 677TT group than in the 677CC + 677CT group (P = 0.016). A total of 25 patients (14.1%) expired due to transplantation related mortality (TRM) during the first 180 days after HSCT. Patients carrying 677TT genotype were more likely to experience early TRM than 677C-carriers. The same pattern was observed in the cumulative TRM rate, and 677TT genotype patients were more prone to cumulative TRM (P = 0.010). This translated into shorter OS for patients with 677TT compared to 677C-carriers (P = 0.010). The 3-year survival after HSCT was 29.9% for 677TT cases and 47.1% for 677C-carriers. The multivariate analysis identified 677TT genotype (HR = 1.775. 95% CI 1.122–2.808, P = 0.014) and non-CR state (HR = 2.841. 95% CI 1.627–4.960, P<0.001) as predictors for survival. In conclusion, the MTHFR 677TT genotype appears to be associated with acute liver GVHD, and represent a risk factor for TRM and survival in patients undergoing HSCT with MTX as

  11. Methylenetetrahydrofolate reductase (MTHFR) deficiency enhances resistance against cytomegalovirus infection.

    PubMed

    Fodil-Cornu, N; Kozij, N; Wu, Q; Rozen, R; Vidal, S M

    2009-10-01

    Folates provide one-carbon units for nucleotide synthesis and methylation reactions. A common polymorphism in the MTHFR gene (677C --> T) results in reduced enzymatic activity, and is associated with an increased risk for neural tube defects and cardiovascular disease. The high prevalence of this polymorphism suggests that it may have experienced a selective advantage under environmental pressure, possibly an infectious agent. To test the hypothesis that methylenetetrahydrofolate reductase (MTHFR) genotype influences the outcome of infectious disease, we examined the response of Mthfr-deficient mice against mouse cytomegalovirus (MCMV) infection. Acute MCMV infection of Mthfr(-/-) mice resulted in early control of cytokine secretion, decreased viral titer and preservation of spleen immune cells, in contrast to Mthfr wild-type littermates. The phenotype was abolished in MTHFR transgenic mice carrying an extra copy of the gene. Infection of primary fibroblasts with MCMV showed a decrease in viral replication and in the number of productively infected cells in Mthfr(+/-) fibroblasts compared with wild-type cells. These results indicate that Mthfr deficiency protects against MCMV infection in vivo and in vitro, suggesting that human genetic variants may provide an advantage in the host response against certain pathogens.

  12. Effect of the methylenetetrahydrofolate reductase gene polymorphisms on homocysteine, folate and vitamin B12 in patients with bipolar disorder and relatives.

    PubMed

    Ozbek, Zeynep; Kucukali, Cem Ismail; Ozkok, Elif; Orhan, Nurcan; Aydin, Makbule; Kilic, Gamze; Sazci, Ali; Kara, Ihsan

    2008-07-01

    We investigated the effect of polymorphic variants of c.1298A>C (Glu429Ala) and c.677C>T (Ala222Val) in methylenetetrahydrofolate (MTHFR) gene on the total homocysteine (tHcy), folate and B12 levels in patients with bipolar disorder, first-degree relatives of patients, and controls. The c.677C>T and c.1298A>C polymorphisms in MTHFR were determined by polymerase chain reaction-restriction fragment length polymorphism in 197 bipolar patients, 278 relatives and 238 controls. tHcy and folate and vitamin B12 levels were measured by Fluorescence Polarization Immunoassay and Electrochemiluminescence, respectively. The tHcy was significantly increased in patients and relatives. In contrast, folate and B12 were significantly lower in patients and relatives. Gender was not considered as a significant determinant in the multivariate analysis. Genotypes of c.1298A>C and c.677C>T were correlated with tHcy, folate and B12. Patients and relatives carrying TT and/or AA and AC genotypes had elevated tHcy and reduced folate and B12 levels. High tHcy but low folate and vitamin B12 levels may be a risk factor for development of bipolar disorder.

  13. Methylenetetrahydrofolate reductase C677T polymorphism and the risks of polycystic ovary syndrome: an updated meta-analysis of 14 studies.

    PubMed

    Wang, Lihong; Xu, Wenting; Wang, Caihong; Tang, Mengyu; Zhou, Yujia

    2017-08-29

    Some studies have reported an association between the Methylenetetrahydrofolate reductase (MTHFR) C667T genetic variant and risk of polycystic ovary syndrome (PCOS), although the results remain controversial. A systematic search was conducted on PubMed, Web of Science, EMBASE, Ovid, Chinese National Knowledge Databases and WanFang databases with relevant keywords. Fourteen studies of sixteen distinct populations involving 1478 PCOS cases and used to conduct a meta-analysis. The T allele was not significantly associated with increased risk of PCOS [OR: 1.08; 95% CI: 0.96-1.21]. In the stratified analysis by ethnicity, the T allele significantly increases risks for the Asian [OR = 1.31; 95% CI: 1.09-1.58] population. No significant associations were detected for the Middle Eastern population [OR = 1.26; 95% CI: 0.96-1.67] and the T allele was found to be protective in the Caucasian population [OR = 0.82; 95% CI: 0.68-0.99]. In conclusion, this meta-analysis suggests that MTHFR C667T variant can increase, decrease, or have no effect on the risks of PCOS depending on the ethnicity.

  14. Plasma folate, methylenetetrahydrofolate reductase (MTHFR), and colorectal cancer risk in three large nested case-control studies

    USDA-ARS?s Scientific Manuscript database

    Few prospective studies have examined the associations between blood levels of folate, in conjunction with methylenetetrahydrofolate reductase (MTHFR) polymorphisms, and colorectal cancer. We evaluated the associations between plasma folate, MTHFR C677T, and A1298C, and colorectal cancer in three la...

  15. Evidence for a Hexaheteromeric Methylenetetrahydrofolate Reductase in Moorella thermoacetica

    PubMed Central

    Mock, Johanna; Wang, Shuning; Huang, Haiyan; Kahnt, Jörg

    2014-01-01

    Moorella thermoacetica can grow with H2 and CO2, forming acetic acid from 2 CO2 via the Wood-Ljungdahl pathway. All enzymes involved in this pathway have been characterized to date, except for methylenetetrahydrofolate reductase (MetF). We report here that the M. thermoacetica gene that putatively encodes this enzyme, metF, is part of a transcription unit also containing the genes hdrCBA, mvhD, and metV. MetF copurified with the other five proteins encoded in the unit in a hexaheteromeric complex with an apparent molecular mass in the 320-kDa range. The 40-fold-enriched preparation contained per mg protein 3.1 nmol flavin adenine dinucleotide (FAD), 3.4 nmol flavin mononucleotide (FMN), and 110 nmol iron, almost as predicted from the primary structure of the six subunits. It catalyzed the reduction of methylenetetrahydrofolate with reduced benzyl viologen but not with NAD(P)H in either the absence or presence of oxidized ferredoxin. It also catalyzed the reversible reduction of benzyl viologen with NADH (diaphorase activity). Heterologous expression of the metF gene in Escherichia coli revealed that the subunit MetF contains one FMN rather than FAD. MetF exhibited 70-fold-higher methylenetetrahydrofolate reductase activity with benzyl viologen when produced together with MetV, which in part shows sequence similarity to MetF. Heterologously produced HdrA contained 2 FADs and had NAD-specific diaphorase activity. Our results suggested that the physiological electron donor for methylenetetrahydrofolate reduction in M. thermoacetica is NADH and that the exergonic reduction of methylenetetrahydrofolate with NADH is coupled via flavin-based electron bifurcation with the endergonic reduction of an electron acceptor, whose identity remains unknown. PMID:25002540

  16. Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, intakes of folate and related B vitamins and colorectal cancer: a case-control study in a population with relatively low folate intake.

    PubMed

    Sharp, Linda; Little, Julian; Brockton, Nigel T; Cotton, Seonaidh C; Masson, Lindsey F; Haites, Neva E; Cassidy, Jim

    2008-02-01

    Folate is key in one-carbon metabolism, disruption of which can interfere with DNA synthesis, repair, and methylation. Efficient one-carbon metabolism requires other B vitamins and the optimal activity of enzymes including 5,10-methylenetetrahydrofolate reductase (MTHFR). We report a population-based case-control study of folate intake, related dietary factors and MTHFR polymorphisms (C677T, A1298C) and colorectal cancer in a population with relatively high colorectal cancer incidence and relatively low folate intake. A total of 264 cases with histologically confirmed incident colorectal cancer and 408 controls participated. There was no clear trend in risk with reported intakes of total, or dietary, folate, riboflavin, vitamin B12 or vitamin B6, nor were there interactions between folate intake and the other B vitamins or alcohol. For C677T, risk decreased with increasing variant alleles (multivariate OR for CT v. CC = 0.77 (95 % CI 0.52, 1.16); OR for TT v. CC = 0.62 (95 % CI 0.31, 1.24)), which, although not statistically significant, was consistent with previous studies. For A1298C, compared with AA subjects, CC subjects had modest, non-significant, reduced risk (multivariate OR = 0.81 (95 % CI 0.45, 1.49)). There were significant interactions between total folate and C677T (P = 0.029) and A1298C (P = 0.025), and total vitamin B6 and both polymorphisms (C677T, P = 0.016; A1298C, P = 0.033), although the patterns observed differed from previous studies. Seen against the setting of low folate intake, the results suggest that the role of folate metabolism in colorectal cancer aetiology may be more complex than previously thought. Investigation of particular folate vitamers (for example, tetrahydrofolate, 5,10-methylenetetrahydrofolate) may help clarify carcinogenesis pathways.

  17. The C677T polymorphism of the methylenetetrahydrofolate reductase gene in Mexican mestizo neural-tube defect parents, control mestizo and native populations.

    PubMed

    Dávalos, I P; Olivares, N; Castillo, M T; Cantú, J M; Ibarra, B; Sandoval, L; Morán, M C; Gallegos, M P; Chakraborty, R; Rivas, F

    2000-01-01

    The C677T mutation of the methylenetetrahydrofolate reductase (MTHFR) gene, associated with the thermolabile form of the enzyme, has reportedly been found to be increased in neural-tube defects (NTD), though this association is still unclear. A group of 107 mestizo parents of NTD children and five control populations: 101 mestizo (M), 50 Huichol (H), 38 Tarahumara (T), 21 Purepecha (P) and 20 Caucasian (C) individuals were typed for the MTHFR C677T variant by the PCR/RFLP (HinfI) method. Genotype frequencies were in agreement with the Hardy-Weinberg expectations in all six populations. Allele frequency (%) of the C677T variant was 45 in NTD, 44 in M, 56 in H, 36 in T, 57 in P, 35 in C. Pairwise inter-population comparisons of allele frequency disclosed a very similar distribution between NTD and M groups (exact test, P=0.92). Among controls, differences between M and individual native groups were NS (0.06

  18. Association study of methylenetetrahydrofolate reductase C677T mutation with cerebral venous thrombosis in an Iranian population.

    PubMed

    Ghaznavi, Habib; Soheili, Zahra; Samiei, Shahram; Soltanpour, Mohammad S

    2015-12-01

    There are limited data on the role of methylenetetrahydrofolate reductase C677T polymorphism and hyperhomocysteinemia as risk factors for cerebral venous thrombosis in Iranian population. We examined a possible association between fasting plasma homocysteine levels, methylenetetrahydrofolate reductase C677T polymorphism, and cerebral venous thrombosis in 50 patients with a diagnosis of cerebral venous thrombosis (20-63 years old) and 75 healthy controls (18-65 years old). Genotyping of the methylenetetrahydrofolate reductase C677T gene polymorphism was performed by PCR-restriction fragment length polymorphism analysis, and homocysteine levels were measured by enzyme immunoassay. Fasting plasma homocysteine levels were significantly higher in cerebral venous thrombosis patients than in controls (P = 0.015). Moreover, plasma homocysteine levels were significantly higher in methylenetetrahydrofolate reductase 677TT genotype compared to 677CT and 677CC genotypes in both cerebral venous thrombosis patients (P = 0.01) and controls (P = 0.03). Neither 677CT heterozygote genotype [odds ratio (OR) 1.35, 95% confidence interval (CI) 0.64-2.84, P = 0.556] nor 677TT homozygote genotype (OR 1.73, 95% CI 0.32-9.21, P = 0.833) was significantly associated with cerebral venous thrombosis. Additionally, no significant differences in the frequency of 677T allele between cerebral venous thrombosis patients and controls were identified (OR 1.31, 95% CI 0.69-2.50, P = 0.512). In conclusion, our study demonstrated that elevated plasma homocysteine levels are significant risk factors for cerebral venous thrombosis. Also, methylenetetrahydrofolate reductase 677TT genotype is not linked with cerebral venous thrombosis, but is a determinant of elevated plasma homocysteine levels.

  19. Influence of Methylenetetrahydrofolate Reductase C677T Polymorphism on the Risk of Lung Cancer and the Clinical Response to Platinum-Based Chemotherapy for Advanced Non-Small Cell Lung Cancer: An Updated Meta-Analysis

    PubMed Central

    Zhu, Ning; Gong, Yi; He, Jian; Xia, Jingwen

    2013-01-01

    Purpose Methylenetetrahydrofolate reductase (MTHFR) has been implicated in lung cancer risk and response to platinum-based chemotherapy in advanced non-small cell lung cancer (NSCLC). However, the results are controversial. We performed meta-analysis to investigate the effect of MTHFR C677T polymorphism on lung cancer risk and response to platinum-based chemotherapy in advanced NSCLC. Materials and Methods The databases of PubMed, Ovid, Wanfang and Chinese Biomedicine were searched for eligible studies. Nineteen studies on MTHFR C677T polymorphism and lung cancer risk and three articles on C677T polymorphism and response to platinum-based chemotherapy in advanced NSCLC, were identified. Results The results indicated that the allelic contrast, homozygous contrast and recessive model of the MTHFR C677T polymorphism were associated significantly with increased lung cancer risk. In the subgroup analysis, the C677T polymorphism was significantly correlated with an increased risk of NSCLC, with the exception of the recessive model. The dominant model and the variant T allele showed a significant association with lung cancer susceptibility of ever smokers. Male TT homozygote carriers had a higher susceptibility, but the allelic contrast and homozygote model had a protective effect in females. No relationship was observed for SCLC in any comparison model. In addition, MTHFR 677TT homozygote carriers had a better response to platinum-based chemotherapy in advanced NSCLC in the recessive model. Conclusion The MTHFR C677T polymorphism might be a genetic marker for lung cancer risk or response to platinum-based chemotherapy in advanced NSCLC. However, our results require further verification. PMID:24142642

  20. The prognostic significance of genetic polymorphisms (Methylenetetrahydrofolate Reductase C677T, Methionine Synthase A2756G, Thymidilate Synthase tandem repeat polymorphism) in multimodally treated oesophageal squamous cell carcinoma.

    PubMed

    Sarbia, M; Stahl, M; von Weyhern, C; Weirich, G; Pühringer-Oppermann, F

    2006-01-30

    The present study retrospectively examined the correlation between the outcome of patients with locally advanced oesophageal squamous cell carcinoma (cT3-4 cN0-1 cM0) after multimodal treatment (radiochemotherapy+/-surgical resection), and the presence of genetic polymorphisms in genes involved in folate metabolism. In total, 68 patients who took part in a prospective multicentric trial received 5-fluorouracil (FU)-based radiochemotherapy, optionally followed by surgery. DNA was extracted from pretherapeutic tumour biopsies and was subsequently genotyped for common genetic polymorphisms of three genes (MTHFR C677T, MTR A2756G, TS tandem repeat polymorphism) involved in folate metabolism and potentially in sensitivity to 5-FU-based chemotherapy. The genotypes were correlated with tumour response to polychemotherapy, radiochemotherapy and with overall survival. Tumours with the MTR wild-type genotype (2756AA) showed a median survival time of 16 months, whereas tumours with an MTR variant genotype (2756AG/2756GG) showed a median survival time of 42 months (P=0.0463). No prognostic impact could be verified for the genotypes of the MTHFR genes and the TS gene. Among tumours treated with radiochemotherapy and subsequent resection, MTR variant genotype showed higher histopathological response rate than tumours with MTR wild-type genotype (P=0.0442). In contrast, no significant relationship between clinically determined tumour regression after polychemotherapy and polymorphisms of the three genes under analysis was observed. In conclusion, pretherapeutic determination of the MTR A2756G polymorphism may predict survival of multimodally treated oesophageal squamous cell carcinomas. Determination of MTHFR C677T and TS tandem repeat polymorphism has no predictive value.

  1. The prognostic significance of genetic polymorphisms (Methylenetetrahydrofolate Reductase C677T, Methionine Synthase A2756G, Thymidilate Synthase tandem repeat polymorphism) in multimodally treated oesophageal squamous cell carcinoma

    PubMed Central

    Sarbia, M; Stahl, M; von Weyhern, C; Weirich, G; Pühringer-Oppermann, F

    2006-01-01

    The present study retrospectively examined the correlation between the outcome of patients with locally advanced oesophageal squamous cell carcinoma (cT3-4 cN0-1 cM0) after multimodal treatment (radiochemotherapy±surgical resection), and the presence of genetic polymorphisms in genes involved in folate metabolism. In total, 68 patients who took part in a prospective multicentric trial received 5-fluorouracil (FU)-based radiochemotherapy, optionally followed by surgery. DNA was extracted from pretherapeutic tumour biopsies and was subsequently genotyped for common genetic polymorphisms of three genes (MTHFR C677T, MTR A2756G, TS tandem repeat polymorphism) involved in folate metabolism and potentially in sensitivity to 5-FU-based chemotherapy. The genotypes were correlated with tumour response to polychemotherapy, radiochemotherapy and with overall survival. Tumours with the MTR wild-type genotype (2756AA) showed a median survival time of 16 months, whereas tumours with an MTR variant genotype (2756AG/2756GG) showed a median survival time of 42 months (P=0.0463). No prognostic impact could be verified for the genotypes of the MTHFR genes and the TS gene. Among tumours treated with radiochemotherapy and subsequent resection, MTR variant genotype showed higher histopathological response rate than tumours with MTR wild-type genotype (P=0.0442). In contrast, no significant relationship between clinically determined tumour regression after polychemotherapy and polymorphisms of the three genes under analysis was observed. In conclusion, pretherapeutic determination of the MTR A2756G polymorphism may predict survival of multimodally treated oesophageal squamous cell carcinomas. Determination of MTHFR C677T and TS tandem repeat polymorphism has no predictive value. PMID:16333305

  2. A new and improved method based on polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for the determination of A1298C mutation in the methylenetetrahydrofolate reductase (MTHFR) gene.

    PubMed

    Machnik, Grzegorz; Zapala, Malgorzata; Pelc, Ewa; Gasecka-Czapla, Monika; Kaczmarczyk, Grzegorz; Okopien, Boguslaw

    2013-01-01

    Intracellular folate homeostasis and metabolism is regulated by numerous genes. Among them, 5,10-methylenetetrahydrofolate reductase (MTHFR) is of special interest because of its involvement in regulation of the homocysteine level in the body as a result of folate metabolism. Moreover, some studies demonstrated that the homocysteine plasma level in individuals may be influenced by polymorphisms present in the MTHFR gene. Two common, clinically relevant mutations have been described: MTHFR C677T and MTHFR A1298C. Although several laboratory techniques allow genotyping of both polymorphisms, PCR-RFLP analysis is simple to perform, relatively cheap, and thus one of the most utilized. In the case of A1298C, the PCR-RFLP technique that utilizes MboII endonuclease class II requires an acrylamide gel electrophoresis, since agarose gel electrophoresis is unable to resolve short deoxyribonucleic acid (DNA) fragments after restriction digestion. Agarose gel electrophoresis is commonly preferred over that of acrylamide. To resolve this inconvenience, a novel PCR-RFLP, AjuI-based method to genotype A1298C alleles has been developed that can be performed on standard agarose gel.

  3. Interactions among methylenetetrahydrofolate reductase (MTHFR) and cystathionine β-synthase (CBS) polymorphisms - a cross-sectional study: multiple heterozygosis as a risk factor for higher homocysteine levels and vaso-occlusive episodes.

    PubMed

    Amaral, F M; Miranda-Vilela, A L; Lordelo, G S; Ribeiro, I F; Daldegan, M B; Grisolia, C K

    2017-02-23

    High plasma homocysteine (Hcy) ​​levels may be responsible for vaso-occlusive episodes and may have acquired and/or genetic causes. This cross-sectional study aimed to investigate the role of methylenetetrahydrofolate reductase (MTHFR; C677T; A1298C) and cystathionine-β-synthase (CBS; T833C/844ins68, G919A) polymorphisms in serum levels of folic acid, vitamin B12 and Hcy, and to verify a possible association between these polymorphisms and the clinical variability. Blood samples of Brazilian patients with a diagnosis of thrombosis were submitted to genotyping by PCR-based methods and serum dosages of folic acid, vitamin B12 and Hcy. Except for the CBS G919A polymorphism, all other genetic markers were in Hardy-Weinberg equilibrium. An increased risk for venous thrombosis was found for the MTHFR 1298CC carriers (OR = 1.688; 95%CI = 0.839-3.398, P = 0.018) and those homozygously mutant for the CBS haplotype 844ins68/T833C (OR = 2.488; 95%CI = 0.501-12.363, P = 0.031), while heterozygous for this CBS haplotype showed an increased risk for higher Hcy levels (OR = 5.900; 95%CI = 1.003-34.691, P = 0.030). Significant interactions were observed among the MTHFR C677T, MTHFR A1298C and CBS haplotype 844ins68/T833C polymorphisms in the results for Hcy levels (P = 0.000), where heterozygous had higher values. Interactions among these polymorphisms can affect serum Hcy levels, where multiple heterozygosis could be a risk factor for vaso-occlusive episodes.

  4. Methylenetetrahydrofolate Reductase C677T: Hypoplastic Left Heart and Thrombosis.

    PubMed

    Spronk, Kimberly J; Olivero, Anthony D; Haw, Marcus P; Vettukattil, Joseph J

    2015-10-01

    The incidence of congenital heart defects is higher in infants with mutation of methylenetetrahydrofolate reductase (MTHFR) gene. The MTHFR C677T gene decreases the bioavailability of folate and increases plasma homocysteine, a risk factor for thrombosis. There have been no reported cases in the literature on the clinical implications of this procoagulable state in the setting of cyanotic heart disease, which itself has prothrombotic predisposition. Two patients with hypoplastic left heart syndrome developed postoperative thrombotic complications, both were homozygous for MTHFR C677T. We present these cases and highlight the implications of MTHFR mutation in the management of complex congenital heart disease. © The Author(s) 2015.

  5. 5,10-Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms: genotype frequency and association with homocysteine and folate levels in middle-southern Italian adults.

    PubMed

    Zappacosta, Bruno; Graziano, Mirella; Persichilli, Silvia; Di Castelnuovo, Augusto; Mastroiacovo, Pierpaolo; Iacoviello, Licia

    2014-01-01

    Two genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene (C677T and A1298C) can influence the plasma homocysteine (Hcy) levels, especially in the presence of an inadequate folate status. The aim of this study was to evaluate the frequencies of C677T and of A1298C MTHFR polymorphisms and their correlation with Hcy and serum folate concentrations in a population of blood donors living in a region of middle-southern Italy (the Molise Region). One hundred ninety seven blood donors were studied for total plasma Hcy, serum folate and C677T and A1298C MTHFR genotypes. The frequency of C677T genotypes was 20.8% (CC), 49.8% (CT) and 29.4% (TT); for the A1298C genotypes: 48.7% (AA), 43.7% (AC) and 7.6% (CC). Hcy and serum folate concentrations were significantly different among genotypes of the C677T polymorphism (CC versus CT versus TT: <0.0001 both for Hcy and folate), with Hcy values increasing, and serum folate decreasing, from CC to TT subjects. Regarding to A1298C polymorphism, the difference among genotypes (AA versus AC versus CC; p: 0.026 for Hcy and 0.014 for serum folate), showed an opposite trend for both parameters, with Hcy higher in the wild-type and lower in the homozygotes and serum folate higher in CC than in AA subjects. In conclusion, we found a high frequency of MTHFR allele associated with high level of Hcy and low levels of folate in an Italian southern population. Copyright © 2013 John Wiley & Sons, Ltd.

  6. Role of polymorphisms in factor V (FV Leiden), prothrombin, plasminogen activator inhibitor type-1 (PAI-1), methylenetetrahydrofolate reductase (MTHFR) and cystathionine β-synthase (CBS) genes as risk factors for thrombophilias.

    PubMed

    Miranda-Vilela, A L

    2012-09-01

    Thrombophilias are defined as a predisposition to thrombosis due to hematological changes which induce blood hypercoagulability; they can be inherited or acquired. They are individually characterized by a large phenotypic variability, even when they occur within the same family. Hereditary thrombophilias are, in most cases, due to changes related to physiological coagulation inhibitors or mutations in the genes of coagulation factors. High levels of plasma homocysteine may also be responsible for vaso-occlusive episodes and may have acquired (nutritional deficiencies of folate and vitamins B6 and B12) and/or genetic causes (mutations in the genes responsible for expression of enzymes involved in the intracellular metabolism of homocysteine). Considering that: (1) thromboses are events of multigenic and multifactorial etiopathology; (2) the presence of mutations in several genes significantly increases the risk of their occurrence; (3) the vascular territory (venous and/or arterial) affected involves different pathophysiological mechanisms and treatments, knowledge of genetic variants that may contribute to the risk and variability of the phenotypic manifestations of these diseases is extremely important. This understanding may provide support for a more individualized and therefore more effective treatment for thrombophilia carriers. Thus, this mini-review aims to address a comprehensive summary of thrombophilias and thrombosis, and discuss the role of polymorphisms in Factor V (FV Leiden), Prothrombin, Plasminogen activator inhibitor type-1 (PAI-1), Methylenetetrahydrofolate reductase (MTHFR) and Cystathionine β-synthase (CBS) genes as risk factors for thrombophilias.

  7. Presence of the methylenetetrahydrofolate reductase gene polymorphism MTHFR C677T in molar tissue but not maternal blood predicts failure of methotrexate treatment for low-risk gestational trophoblastic neoplasia.

    PubMed

    Qu, Jia; Usui, Hirokazu; Kaku, Hiroshi; Shozu, Makio

    2017-01-05

    Gestational trophoblastic neoplasia (GTN) is a rare tumor, and its genomic constitution is different from the maternal genome because of its gestational origin. Methotrexate (MTX) is a standard chemotherapeutic agent for low-risk GTN. An association between polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) gene and MTX treatment outcome has been reported in various diseases. Thus, we examined the association between clinical outcome and MTHFR polymorphisms in both tumor and blood DNA of low-risk GTN patients. MTHFR C677T (rs1801133) and A1298C (rs1801131) were genotyped using high-resolution melting assays in 62 Japanese low-risk GTN patients and in 52 antecedent molar tissues. We compared the genotypes of MTHFR polymorphisms with the clinical outcome of 5-day MTX treatment. Twenty-five patients entered remission and 37 patients developed drug resistance or adverse effects that necessitated a drug change. The MTHFR 677T allele in molar tissue was significantly related to the need for drug change (P=0.006; odds ratio [OR], 3.13; 95% confidence interval [CI], 1.31-7.49), in contrast to MTHFR 1298C (P=0.18; OR, 0.63; 95% CI, 0.32-1.25). The MTHFR 677T and 1298C alleles obtained from patients' blood DNA were not related to MTX treatment outcome (P=0.49; OR 1.31; 95% CI, 0.61-2.91 and P=0.10; OR 0.52; 95% CI, 0.22-1.15, respectively). These data demonstrate for the first time that the genotype of MTHFR 677TT in molar tissue is associated with ineffective MTX treatment in Japanese low-risk GTN patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Methylenetetrahydrofolate reductase (MTHFR) polymorphism A1298C (Glu429Ala) predicts decline in renal function over time in the African-American Study of Kidney Disease and Hypertension (AASK) Trial and Veterans Affairs Hypertension Cohort (VAHC)

    PubMed Central

    Salem, Rany M.; Lipkowitz, Michael S.; Bhatnagar, Vibha; Pandey, Braj; Schork, Nicholas J.; O’Connor, Daniel T.

    2012-01-01

    Background. Hyperhomocysteinemia is associated with increased venous thrombosis and cardiovascular disease (CVD). Mutations in the human methylenetetrahydrofolate reductase (MTHFR) gene have been associated with increased homocysteine levels and risks of CVD in various populations including those with kidney disease. Here, we evaluated the influence of MTHFR variants on progressive loss of kidney function. Methods. We analyzed 821 subjects with hypertensive nephrosclerosis from the longitudinal National Institute of Diabetes and Digestive and Kidney Diseases African-American Study of Kidney Disease and Hypertension (AASK) Trial to determine whether decline in glomerular filtration rate (GFR) over ∼4.2 years was predicted by common genetic variation within MTHFR at non-synonymous positions C677T (Ala222Val) and A1298C (Glu429Ala) or by MTHFR haplotypes. The effect on GFR decline was then supported by a study of 1333 subjects from the San Diego Veterans Affairs Hypertension Cohort (VAHC), followed over ∼4.5 years. Linear effect models were utilized to determine both genotype [single-nucleotide polymorphism (SNP)] and genotype (SNP)-by-time interactions. Results. In AASK, the polymorphism at A1298C predicted the rate of GFR decline: A1298/A1298 major allele homozygosity resulted in a less pronounced decline of GFR, with a significant SNP-by-time interaction. An independent follow-up study in the San Diego VAHC subjects supports that A1298/A1298 homozygotes have the greatest estimated GFR throughout the study. Haplotype analysis with C677T yielded concurring results. Conclusion. We conclude that the MTHFR-coding polymorphism at A1298C is associated with renal decline in African-Americans with hypertensive nephrosclerosis and is supported by a veteran cohort with a primary care diagnosis of hypertension. Further investigation is needed to confirm such findings and to determine what molecular mechanism may contribute to this association. PMID:21613384

  9. Relationship between glutathione S-transferase P1 (GSTP1), X-ray repair cross complementing group 1 (XRCC1) and 5,10-methylenetetrahydrofolate reductase (5,10-MTHFR) gene polymorphisms and response to chemotherapy in advanced gastric cancer.

    PubMed

    Ji, Mei; Xu, Bin; Jiang, Jing-Ting; Wu, Jun; Li, Xiao-Dong; Zhao, Wei-Qing; Zhang, Hong-Yu; Zhou, Wen-Jie; Wu, Chang-Ping

    2013-01-01

    Our study aimed to investigate the relationship between glutathione S-transferase P1 (GSTP1), 5,10-methylenetetrahydrofolate reductase (5,10-MTHFR) and X-ray repair cross complementing group 1 (XRCC1) gene polymorphisms and the response to chemotherapy in advanced gastric cancer. 59 cases of advanced gastric cancer were enrolled. All patients were treated with the DCF regimen comprising docetaxel, cisplatin, and 5-fluorouracil. All patients' genotypes regarding GSTP1, XRCC1, and 5,10-MTHFR were analyzed by polymerase chain reaction/ligase detection reaction (PCR-LDR). There were 15 (25.42%) cases of G/G genotype, 21 (35.59%) of G/A genotype, and 23 (38.98%) of A/A genotype for GSTP1, 16 (27.12%) cases of A/A genotype, 18 (30.51%) of G/A genotype, and 25 (42.37%) of G/G genotype for XRCC1, and 21 (35.59%) cases of C/C genotype, 22 (37.29%) of C/T genotype, and 16 (27.12%) of T/T genotype for 5,10-MTHFR. After 2 cycles of chemotherapy, there were 4 cases of complete remission, 14 of partial remission, 19 of stable disease, and 22 of advanced disease, with a total effective rate of 30.51%. Better survival was shown for GSTP1 G/G genotype, XRCC1 A/A genotype, and 5,10-MTHFR T/T genotype (p < 0.05). The gene polymorphisms of GSTP1 G/G, XRCC1 A/A, and 5,10-MTHFR T/T have clinical value for predicting the response to the DCF regimen for advanced gastric cancer. © 2013 S. Karger GmbH, Freiburg.

  10. Seven novel mutations in the methylenetetrahydrofolate reductase gene and genotype/phenotype correlations in severe methylenetetrahydrofolate reductase deficiency

    SciTech Connect

    Goyette, P.; Frosst, P.; Rosenblatt, D.S.; Rozen. R.

    1995-05-01

    5-Methyltetrahydrofolate, the major form of folate in plasma, is a carbon donor for the remethylation of homocysteine to methionine. This form of folate is generated from 5,10-methylenetetrahydrofolate through the action of 5,10-methylenetetrahydrofolate reductase (MTHFR), a cytosolic flavoprotein. Patients with an autosomal recessive severe deficiency of MTHFR have homocystinuria and a wide range of neurological and vascular disturbances. We have recently described the isolation of a cDNA for MTHFR and the identification of two mutations in patients with severe MTHFR deficiency. We report here the characterization of seven novel mutations in this gene: six missense mutations and a 5{prime} splice-site defect that activates a cryptic splice in the coding sequence. We also present a preliminary analysis of the relationship between genotype and phenotype for all nine mutations identified thus far in this gene. A nonsense mutation and two missense mutations (proline to leucine and threonine to methionine) in the homozygous state are associated with extremely low activity (0%-3%) and onset of symptoms within the 1st year of age. Other missense mutations (arginine to cysteine and arginine to glutamine) are associated with higher enzyme activity and later onset of symptoms. 19 refs., 4 figs., 2 tabs.

  11. Relationship between three polymorphisms of methylenetetrahydrofolate reductase (MTHFR C677T, A1298C, and G1793A) gene and risk of prostate cancer: a case-control study.

    PubMed

    Safarinejad, Mohammad Reza; Shafiei, Nayyer; Safarinejad, Shiva

    2010-11-01

    We hypothesized that genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR) gene are associated with prostate cancer risk. We genotyped three MTHFR polymorphisms (C677T, A1298C, and G1793A) and measured serum total homocysteine (tHcy), folate, and vitamin B12 levels in a case-control study of 174 cases and 348 normal healthy controls. The cancer-free controls were frequency matched to the cases by age (±2 years), educational level, occupational status, ethnicity, and smoking status. We found that the MTHFR 677TT and 1298CC genotypes were associated with an about 40% reduction in risk of prostate cancer (adjusted OR = 0.59, 95% CI = 0.41-0.94, and adjusted OR = 0.58, 95% CI = 0.32-0.91, respectively) compared to the 677CC, and 1298AA genotypes. The combined variant genotypes of 1298AC + 677CC were associated with a 30% reduction in risk of prostate cancer (OR = 0.70; 95% CI = 0.53-0.79). In contrast, the variant genotypes of 1793GA + 677CT were associated with slightly increased risk for prostate cancer (OR = 1.64; 95% CI = 0.86-2.15). Regarding prostate cancer aggressiveness, the 677TT genotype was associated with more than 50% decreased risk of high-grade prostate cancer (Gleason score >7) compared with the 677CC and 677CT genotypes (OR = 0.35, 95% CI = 0.24-0.64; P = 0.001). There was no significant difference in plasma levels of tHcy, folate, and vitamin B12 between the two groups with any genotypes. These data suggest that all three MTHFR polymorphisms may play a pivotal role in the developing prostate cancer. Larger studies in different ethnic populations and incorporating dietary folate intake are needed to replicate our findings.

  12. Assessing the association between the methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphism and blood folate concentrations: a systematic review and meta-analysis of trials and observational studies.

    PubMed

    Tsang, Becky L; Devine, Owen J; Cordero, Amy M; Marchetta, Claire M; Mulinare, Joseph; Mersereau, Patricia; Guo, Jing; Qi, Yan Ping; Berry, Robert J; Rosenthal, Jorge; Crider, Krista S; Hamner, Heather C

    2015-06-01

    The methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphism is a risk factor for neural tube defects. The T allele produces an enzyme with reduced folate-processing capacity, which has been associated with lower blood folate concentrations. We assessed the association between MTHFR C677T genotypes and blood folate concentrations among healthy women aged 12-49 y. We conducted a systematic review of the literature published from January 1992 to March 2014 to identify trials and observational studies that reported serum, plasma, or red blood cell (RBC) folate concentrations and MTHFR C677T genotype. We conducted a meta-analysis for estimates of percentage differences in blood folate concentrations between genotypes. Forty studies met the inclusion criteria. Of the 6 studies that used the microbiologic assay (MA) to measure serum or plasma (S/P) and RBC folate concentrations, the percentage difference between genotypes showed a clear pattern of CC > CT > TT. The percentage difference was greatest for CC > TT [S/P: 13%; 95% credible interval (CrI): 7%, 18%; RBC: 16%; 95% CrI: 12%, 20%] followed by CC > CT (S/P: 7%; 95% CrI: 1%, 12%; RBC: 8%; 95% CrI: 4%, 12%) and CT > TT (S/P: 6%; 95% CrI: 1%, 11%; RBC: 9%; 95% CrI: 5%, 13%). S/P folate concentrations measured by using protein-binding assays (PBAs) also showed this pattern but to a greater extent (e.g., CC > TT: 20%; 95% CrI: 17%, 22%). In contrast, RBC folate concentrations measured by using PBAs did not show the same pattern and are presented in the Supplemental Material only. Meta-analysis results (limited to the MA, the recommended population assessment method) indicated a consistent percentage difference in S/P and RBC folate concentrations across MTHFR C677T genotypes. Lower blood folate concentrations associated with this polymorphism could have implications for a population-level risk of neural tube defects. © 2015 American Society for Nutrition.

  13. Genetic variants in 3'-UTRs of methylenetetrahydrofolate reductase (MTHFR) predict colorectal cancer susceptibility in Koreans.

    PubMed

    Jeon, Young Joo; Kim, Jong Woo; Park, Hye Mi; Kim, Jung O; Jang, Hyo Geun; Oh, Jisu; Hwang, Seong Gyu; Kwon, Sung Won; Oh, Doyeun; Kim, Nam Keun

    2015-06-05

    Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) play important roles in tumor development, progression, and metastasis. Moreover, recent studies have reported that a number of 3'-UTR polymorphisms potentially bind to specific microRNAs in a variety of cancers. The aim of this study was to investigate the association of four MTHFR polymorphisms, 2572C>A [rs4846049], 4869C>G [rs1537514], 5488C>T [rs3737967], and 6685T>C [rs4846048] with colorectal cancer (CRC) in Koreans. A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of MTHFR 3'-UTR polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis or TaqMan allelic discrimination assay. We found that MTHFR 2572C>A, 4869C>G, and 5488C>T genotypes were substantially associated with CRC susceptibility. Of the potentially susceptible polymorphisms, MTHFR 2572C>A was associated with increased homocysteine and decreased folate levels in the plasma based on MTHFR 677CC. Our study provides the evidences for 3'-UTR variants in MTHFR gene as potential biomarkers for use in CRC prevention.

  14. Distribution of common methylenetetrahydrofolate reductase gene mutations in patients with obstructive sleep apnoea.

    PubMed

    Bekci, T T; Kocak, N; Kesli, R

    2009-01-01

    Homocysteine levels have been investigated in patients with obstructive sleep apnoea syndrome (OSAS), a syndrome associated with a high level of comorbid cardiovascular disease (CVD). While significant increases in homocysteine levels have been observed in OSAS patients with CVD, no increases have been noted in OSAS patients without CVD. This study was designed to investigate the methylenetetrahydrofolate reductase (MTHFR) gene, which is essential for homocysteine metabolism and has been shown to have a causal role in the development of CVD. Eighty subjects, 30 diagnosed with OSAS by polysomnography and 50 controls (healthy volunteers with no symptoms of OSAS) were enrolled. Two mutations in the MTHFR gene were investigated using polymerase chain reactions and restriction fragment length polymorphisms. No significant differences were found in mean age, body mass index, homocysteine levels, or MTHFR allele or genotype distributions between patient and control groups.

  15. Severe scoliosis in a patient with severe methylenetetrahydrofolate reductase deficiency.

    PubMed

    Munoz, Tatiana; Patel, Jinesh; Badilla-Porras, Ramses; Kronick, Jonathan; Mercimek-Mahmutoglu, Saadet

    2015-01-01

    Severe methylenetetrahydrofolate reductase (MTHFR) deficiency is a rare autosomal recessively inherited inborn error of folate metabolism. We report a new patient with severe MTHFR deficiency who presented at age 4 months with early onset severe scoliosis associated with severe hypotonia. Markedly decreased MTHFR enzyme activity (0.3 nmoles CHO/mg protein/h; reference range>9) and compound heterozygous mutations (c. 1304T>C; p.Phe435Ser and c.1539dup; p.Glu514Argfs∗24) in the MTHFR gene confirmed the diagnosis. She was treated with vitamin B12, folic acid and betaine supplementation and showed improvements in her developmental milestones and hypotonia. To the best of our knowledge, this is the first patient with MTHFR deficiency reported with severe early onset scoliosis. Despite the late diagnosis and treatment initiation, she showed favorable short-term neurodevelopmental outcome. This case suggests that homocysteine measurement should be included in the investigations of patients with developmental delay, hypotonia and scoliosis within first year of life prior to organizing genetic investigations.

  16. Betaine rescue of an animal model with methylenetetrahydrofolate reductase deficiency

    PubMed Central

    2004-01-01

    MTHFR (methylenetetrahydrofolate reductase) catalyses the synthesis of 5-methyltetrahydrofolate, the folate derivative utilized in homocysteine remethylation to methionine. A severe deficiency of MTHFR results in hyperhomocysteinaemia and homocystinuria. Betaine supplementation has proven effective in ameliorating the biochemical abnormalities and the clinical course in patients with this deficiency. Mice with a complete knockout of MTHFR serve as a good animal model for homocystinuria; early postnatal death of these mice is common, as with some neonates with low residual MTHFR activity. We attempted to rescue Mthfr−/− mice from postnatal death by betaine supplementation to their mothers throughout pregnancy and lactation. Betaine decreased the mortality of Mthfr−/− mice from 83% to 26% and significantly improved somatic development from postnatal day 1, compared with Mthfr−/− mice from unsupplemented dams. Biochemical evaluations demonstrated higher availability of betaine in suckling pups, decreased accumulation of homocysteine, and decreased flux through the trans-sulphuration pathway in liver and brain of Mthfr−/− pups from betaine-supplemented dams. We observed disturbances in proliferation and differentiation in the cerebellum and hippocampus in the knockout mice; these changes were ameliorated by betaine supplementation. The dramatic effects of betaine on survival and growth, and the partial reversibility of the biochemical and developmental anomalies in the brains of MTHFR-deficient mice, emphasize an important role for choline and betaine depletion in the pathogenesis of homocystinuria due to MTHFR deficiency. PMID:15217352

  17. Mutation Update and Review of Severe Methylenetetrahydrofolate Reductase Deficiency.

    PubMed

    Froese, D Sean; Huemer, Martina; Suormala, Terttu; Burda, Patricie; Coelho, David; Guéant, Jean-Louis; Landolt, Markus A; Kožich, Viktor; Fowler, Brian; Baumgartner, Matthias R

    2016-05-01

    Severe 5,10-methylenetetrahydrofolate reductase (MTHFR) deficiency is caused by mutations in the MTHFR gene and results in hyperhomocysteinemia and varying severity of disease, ranging from neonatal lethal to adult onset. Including those described here, 109 MTHFR mutations have been reported in 171 families, consisting of 70 missense mutations, 17 that primarily affect splicing, 11 nonsense mutations, seven small deletions, two no-stop mutations, one small duplication, and one large duplication. Only 36% of mutations recur in unrelated families, indicating that most are "private." The most common mutation is c.1530A>G (numbered from NM_005957.4, p.Lys510 = ) causing a splicing defect, found in 13 families; the most common missense mutation is c.1129C>T (p.Arg377Cys) identified in 10 families. To increase disease understanding, we report enzymatic activity, detected mutations, and clinical onset information (early, <1 year; or late, >1 year) for all published patients available, demonstrating that patients with early onset have less residual enzyme activity than those presenting later. We also review animal models, diagnostic approaches, clinical presentations, and treatment options. This is the first large review of mutations in MTHFR, highlighting the wide spectrum of disease-causing mutations. © 2016 WILEY PERIODICALS, INC.

  18. Methylenetetrahydrofolate reductase (MTHFR) gene C677T, A1298C and G1793A polymorphisms: association with risk for clear cell renal cell carcinoma and tumour behaviour in men.

    PubMed

    Safarinejad, M R; Shafiei, N; Safarinejad, S

    2012-05-01

    Methylenetetrahydrofolate reductase (MTHFR) plays a crucial role in regulating folate metabolism, which affects DNA synthesis and methylation. This study investigated whether MTHFR C677T, A1298C and G1793A polymorphisms modified clear cell renal cell carcinoma (CCRCC) risk independently as well as in combination with serum total homocysteine (Hcy) and folate levels. A case-control study of 152 cases (men) and 304 age-matched healthy controls was conducted in one geographical area of Iran. Genotyping of MTHFR gene polymorphisms was carried out using a polymerase chain reaction restriction fragment length polymorphism technique. Serum levels of total Hcy, folate and vitamin B12 were also determined. The MTHFR 677T and 1298C allele frequencies were 42.8 and 47.4% in cases, compared with 33.7 and 33.1% in controls. After controlling for confounding factors, a significant increase in CCRCC risk was found among carriers of the 677CT genotype compared with those with the 677CC genotype (odds ratio 2.21, 95% confidence interval 1.31-3.76), with a significant trend (P=0.014). Statistically significant odds ratios were also found in patients homozygous for MTHFR C677T, who have a 1.58-fold higher risk of developing CCRCC (95% confidence interval=1.21-2.44; P=0.024). Compared with the MTHFR 677CC genotype, the odds ratio (95% confidence interval) for the MTHFR 677TT genotype was 6.18 (95% confidence interval=4.75-8.34) for stage IV cancer and 4.68 (95% confidence interval=2.72-6.54) for grade 3 CCRCC (both P=0.0001). After adjustment for selected variants, the MTHFR 1298AC genotype showed a significantly increased risk of CCRCC compared with the wild-type (odds ratio=3.71, 95% confidence interval=2.22-5.33; P=0.001), and the 1298C allele carrier showed a positive association with the risk of CCRCC compared with the wild-type (odds ratio=3.9, 95% confidence interval=2.55-6.02; P=0.001). Furthermore, subjects carrying at least one copy of the variant allele showed a 4.4 times

  19. Folic acid rivals methylenetetrahydrofolate reductase (MTHFR) gene-silencing effect on MEPM cell proliferation and apoptosis.

    PubMed

    Xiao, Wen-Lin; Wu, Min; Shi, Bing

    2006-11-01

    It's clear that environmental factors play a role in the aetiology of orofacial clefting (OFC) and an important area of future research will be to unravel interactions that occur between candidate genes and environmental factors during early development of the embryo. Periconceptional folic acid supplementation may reduce the risk of OFC. Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene reduce availability of 5-methylenetetrahydrofolate, the predominant circulating form of folic acid. To determine the effect of MTHFR gene mutation on murine embryonic palatal mesenchymal (MEPM) cells and the interaction with folic acid supplement, we used RNAi study in the primary cultures of MEPM cells. The cells of MTHFR gene silencing grew slower and the apoptosis cell number was more than the cells of control. Supplement with 20 microg/ml folic acid was the best to preventing teratogenic effect of MTHFR gene silencing. By flow cytometry analysis of cell cycle, results were shown that the MEPM cells were retarded in G(0)/G(1) after MTHFR gene silencing. While using 20 microg/ml folic acid supplements could make cell transit the G(1)/S restriction point and the cells growth was close to normal level.

  20. The one-carbon-cycle and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in recurrent major depressive disorder; influence of antidepressant use and depressive state?

    PubMed

    Lok, A; Mocking, R J T; Assies, J; Koeter, M W; Bockting, C L; de Vries, G J; Visser, I; Derks, E M; Kayser, M; Schene, A H

    2014-09-01

    An important biological factor suggested in the pathophysiology of (recurrent) Major Depressive Disorder (MDD) concerns a polymorphism in a gene encoding for the MTHFR-enzyme of the one-carbon (1-C)-metabolism. Integratively investigating key 1-C-components (folate, homocysteine, vitamin B6 and B12), including the possible effects of antidepressant medication and depressive state, could provide more insight in the possible association between the MTHFR-polymorphism and recurrent MDD. We compared the MTHFR C677T-polymorphism together with the key 1-C-components in clinically ascertained patients with recurrent MDD (n=137) to age- and gender-matched healthy controls (n=73). First, patients had lower folate (t=2.25; p=.025) as compared to controls; a difference that resolved after correction for demographics (t=1.22; p=.223). Second, patients that were depressed during sampling had lower vitamin B6 (t=-2.070; p=.038) and higher homocysteine (t=2.404; p=.016) compared to those in remission. Finally, current use of antidepressants had no influence on the 1-C-components. Despite investigation of a specific recurrently depressed patient population, we found no clear associations with the 1-C-cycle, except for higher homocysteine and lower vitamin B6 during the depressed state. This suggests that 1-C-cycle alterations in MDD are state-associated, possibly resulting from high levels of acute (psychological) stress, and may provide a treatment target to reduce cardiovascular risk in this population. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Association of methylenetetrahydrofolate reductase and methionine synthase polymorphisms with breast cancer risk and interaction with folate, vitamin B6, and vitamin B 12 intakes.

    PubMed

    Jiang-Hua, Qiao; De-Chuang, Jiao; Zhen-Duo, Lu; Shu-de, Cui; Zhenzhen, Liu

    2014-12-01

    We assessed the association between dietary intake of folate and the MTHFR genotype with breast cancer in a Chinese population, with additional analysis of the interactions of gene polymorphisms and dietary intake of folate, vitamin B6, and vitamin B12. A case-control study was performed, and 535 patients with newly diagnosed breast cancer and 673 controls were enrolled into this study. The MTHFR 667TT genotype (odds ratio (OR) = 1.82, 95 % confidence interval (CI) = 1.24-2.97) and T allele (OR 0= 1.48, 95 % CI = 1.15-1.78) were correlated with a moderately significant increased risk of breast cancer when compared with the CC genotype. Individuals carrying the MTR 2756GG genotype (OR = 1.66, 95 % CI = 1.16-2.56) and G allele (OR = 1.42, 95 % CI = 1.26-1.81) had a higher risk of breast cancer when compared with subjects with the AA genotype. The MTHFR 667 T allele and MTR 2756 G allele were associated with a higher risk of breast cancer in individuals with low folate intake, vitamin B6, and vitamin B12, but the association disappeared among subjects with moderate and high intake of folate, vitamin B6, and vitamin B12. This case-control study found that the MTHFR C677T and MTR A2756G polymorphisms are associated with risk of breast cancer, and folate, vitamin B6, and vitamin B12 intakes influence these associations.

  2. Maternal Supplementary Folate Intake, Methylenetetrahydrofolate Reductase (MTHFR) C677T and A1298C Polymorphisms and the Risk of Orofacial Cleft in Iranian Children

    PubMed Central

    Ebadifar, Asghar; KhorramKhorshid, Hamid Reza; Kamali, Koorosh; Salehi Zeinabadi, Mehdi; Khoshbakht, Tayyebeh; Ameli, Nazila

    2015-01-01

    Background: The purpose of this study was to describe the association of MTHFR gene single nucleotide polymorphisms (C677T and A1298C) and maternal supplementary folate intake with orofacial clefts in the Iranian population. Methods: In this case-control study, peripheral venous blood was taken from 65 patients with orofacial clefts and 215 unaffected controls for DNA extraction and kept in EDTA for further analysis. The genotyping was carried out using Polymerase Chain Reaction (PCR) followed by Restriction Fragment Length Polymorphism (RFLP) and gel electrophoresis. Data were analyzed using Chi square test and logistic regression tests. Results: Genotype frequencies of 677TT were reported to be 13.5 and 36.1% in controls and CL/P patients, respectively, which showed a significant difference compared to CC as reference (OR=4.118; 95% CI=1.997–8.492; p=0.001). Conversely, 1298CC with frequencies of 10.8 and 12.7% in controls and patients, respectively, showed no significant difference compared to AA (OR=2.359; 95% CI=0.792–7.023; p=0.123). Comparing patients whose mothers did not report the folate supplement intake during pregnancy, to controls, it was observed that lack of folate intake was a predisposing factor for having a child with oral clefts (OR=5/718, p=0.000). Conclusion: Children carrying the 677TT variant of the MTHFR gene may have an increased risk of CL/P. In addition, the finding that the risk associated with this allele was obviously higher when the mothers didn’t use folic acid, supports the hypothesis that folic acid may play a role in the etiology of CL/P. PMID:26140186

  3. Association of C677T transition of the human methylenetetrahydrofolate reductase (MTHFR) gene with male infertility.

    PubMed

    Karimian, Mohammad; Colagar, Abasalt Hosseinzadeh

    2016-04-01

    The human methylenetetrahydrofolate reductase (MTHFR) gene encodes one of the key enzymes in folate metabolism. This gene is located on chromosome 1 (1p36.3), which has 12 exons. The aim of the present study was to investigate the possible association of the two (C677T and A1298C) polymorphisms of this gene with male infertility. In a case-control study, 250 blood samples were collected from IVF centres in Sari and Babol (Iran): 118 samples were from oligospermic men and 132 were from controls. Two single nucleotide polymorphisms of the MTHFR genotype were detected using polymerase chain reaction-restriction fragment length polymorphism. There was no association found between the A1298C variant and male infertility. However, carriers of the 677T allele (CT and TT genotypes) were at a higher risk of infertility than individuals with other genotypes (odds ratio 1.84; 95% confidence interval 1.11-3.04; P=0.0174). Structural analysis of human MTHFR flavoprotein showed that C677T transition played an important role in the change in affinity of the MTHFR-Flavin adenine dinucleotide binding site. Based on our results, we suggest that C677T transition in MTHFR may increase the risk of male infertility, and detection of the C677T polymorphism biomarker may be helpful in the screening of idiopathic male infertility.

  4. Status of vitamin B-12 and B-6 but not of folate, homocysteine and the methylenetetrahydrofolate reductase C677T polymorphism are associated with impaired cognition and depression in adults

    USDA-ARS?s Scientific Manuscript database

    The C677T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene differs in frequency in different ethnic groups which have differing prevalence of age-related cognitive impairments. We used a battery of neuropsychological tests to examine association of the MTHFR C677T polymorphism w...

  5. Methylenetetrahydrofolate reductase (MTHFR) genotype, smoking habit, metastasis and oral cancer in Taiwan.

    PubMed

    Tsai, Chia-Wen; Hsu, Chia-Fang; Tsai, Ming-Hsui; Tsou, Yung-An; Hua, Chun-Hung; Chang, Wen-Shin; Lin, Cheng-Chieh; Bau, Da-Tian

    2011-06-01

    The aim of this study was to evaluate the association and interaction of genotypic polymorphism in methylenetetrahydrofolate reductase (MTHFR) with smoking habits and oral cancer in Taiwan. Two well-known polymorphic variants of MTHFR, C677T (rs1801133) and A1298C (rs1801131), were analyzed in association with oral cancer risk, and their joint effects with individual smoking habits on oral cancer risk are discussed. In total, 620 oral cancer patients and 620 non-cancer controls in central Taiwan were recruited and genotyped. The MTHFR C677T genotype, but not the A1298C, was differently distributed between the oral cancer and control groups. The T allele of MTHFR C677T was significantly more frequently found in controls than in oral cancer patients. Joint effects of smoking and MTHFR C677T genotype significantly affected oral cancer susceptibility. The MTHFR C677T CT and TT genotypes in association with smoking conferred lower odds ratios of 0.66 and 0.54 (95% confidence interval=0.49-0.82 and 0.39-0.86), respectively. Those patients with MTHFR C677T CT and TT genotypes also had a lower risk of oral cancer metastasis. MTHFR C677T genotype may have joint effects with smoking on oral carcinogenesis, and may be a useful biomarker for prediction and prognosis of oral cancer.

  6. The association between end-stage diabetic nephropathy and methylenetetrahydrofolate reductase genotype with macroangiopathy in type 2 diabetes mellitus.

    PubMed

    Hasegawa, G; Obayashi, H; Kamiuchi, K; Nakai, M; Kanatsuna, T; Yamaguchi, M; Tanaka, T; Shigeta, H; Fujii, M; Yoshikawa, T; Nakamura, N

    2003-05-01

    The T/T genotype of the methylenetetrahydrofolate reductase C677 T gene polymorphism is associated with elevated homocysteine levels and presumably with increased atherosclerotic risk. We evaluated the interaction between this gene polymorphism and end-stage diabetic nephropathy on the observed prevalence of macroangiopathy in type 2 diabetes mellitus. The methylenetetrahydrofolate reductase 677 C/T genotypes were determined in 174 type 2 diabetic patients: 80 with and 94 without renal failure due to diabetic nephropathy. In the patients with renal failure, the T/T genotype and T allele were significantly associated with macroangiopathy (T/T; 31 % vs. 2 %, P = 0.0001 T allele; 59 % vs. 29 %, P = 0.00014), whereas the associations were not significant in the patients without renal failure. In the multiple logistic regression analysis, age (10 years OR 4.05 [1.79 - 9.31], P < 0.0005) and 677 T allele (6.84 [2.12 - 22.05], P = 0.0013) were significantly associated with macroangiopathy in the patients with renal failure. In conclusion, this study demonstrated that the 677 T/T genotype and T allele of MTHFR were significantly associated with macroangiopathy in type 2 diabetic patients with renal failure. The MTHFR 677 T allele, together with renal dysfunction due to diabetic nephropathy, could be a strong risk factor for atherosclerotic disease.

  7. Folate metabolism gene 5,10-methylenetetrahydrofolate reductase (MTHFR) is associated with ADHD in myelomeningocele patients.

    PubMed

    Spellicy, Catherine J; Northrup, Hope; Fletcher, Jack M; Cirino, Paul T; Dennis, Maureen; Morrison, Alanna C; Martinez, Carla A; Au, Kit Sing

    2012-01-01

    The objective of this study was to examine the relation between the 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene and behaviors related to attention- deficit/hyperactivity disorder (ADHD) in individuals with myelomeningocele. The rationale for the study was twofold: folate metabolizing genes, (e.g. MTHFR), are important not only in the etiology of neural tube defects but are also critical to cognitive function; and individuals with myelomeningocele have an elevated incidence of ADHD. Here, we tested 478 individuals with myelomeningocele for attention-deficit hyperactivity disorder behavior using the Swanson Nolan Achenbach Pelham-IV ADHD rating scale. Myelomeningocele participants in this group for whom DNAs were available were genotyped for seven single nucleotide polymorphisms (SNPs) in the MTHFR gene. The SNPs were evaluated for an association with manifestation of the ADHD phenotype in children with myelomeningocele. The data show that 28.7% of myelomeningocele participants exhibit rating scale elevations consistent with ADHD; of these 70.1% had scores consistent with the predominantly inattentive subtype. In addition, we also show a positive association between the SNP rs4846049 in the 3'-untranslated region of the MTHFR gene and the attention-deficit hyperactivity disorder phenotype in myelomeningocele participants. These results lend further support to the finding that behavior related to ADHD is more prevalent in patients with myelomeningocele than in the general population. These data also indicate the potential importance of the MTHFR gene in the etiology of the ADHD phenotype.

  8. Expression and clinical significance of methylenetetrahydrofolate reductase in patients with colorectal cancer.

    PubMed

    Odin, Elisabeth; Wettergren, Yvonne; Carlsson, Göran; Danenberg, Peter V; Termini, Angelo; Willén, Roger; Gustavsson, Bengt

    2006-01-01

    The aim of the study was to investigate the influence of methylenetetrahydrofolate reductase (MTHFR) gene expression levels and MTHFR polymorphism C677T on the outcome of patients with colorectal cancer (CRC). Furthermore, we wanted to evaluate the interaction between MTHFR and thymidylate synthase (TS) and folylpolyglutamate synthase (FPGS) and to investigate the impact of folate concentration on patients with CRC with different MTHFR genotypes. The frequency of MTHFR polymorphism C677T was determined (n = 147), and gene expression levels of MTHFR, TS, and FPGS were quantified with real-time polymerase chain reaction (n = 157). Reduced folates in tissue were measured with a binding assay (n = 40). We observed a significantly lower concentration of tetrahydrofolate (THF) in patients with CT or TT genotypes compared with patients having the CC genotype. Twenty-six patients with Dukes A to C tumors who had not been subjected to chemotherapy relapsed. Out of these, 18 had CT or TT genotypes, and only 8 had the CC genotype (P = 0.045). Furthermore, 75 patients did not relapse, and out of these, 35 had CT or TT genotypes, and 40 had the CC genotype. The relative gene expression level of MTHFR in patients subgrouped by CC and CT or TT genotypes was significantly lower in carcinomas compared with adjacent mucosa (P < 0.0001 and P < 0.0001, respectively). A significant difference in MTHFR expression level was also observed according to MTHFR genotype in the tumor but not in adjacent mucosa. The MTHFR gene expression level in mucosa was a prognostic parameter independent of the clinicopathologic factors with regard to survival for patients with MTHFR C677T mutation. Our results showed that it is possible to identify patients with CRC with a higher risk for relapse. Furthermore, patients with a mutant genotype in combination with low MTHFR expression have a poor clinical outcome.

  9. The Association of Methylenetetrahydrofolate Reductase Genotypes with the Risk of Childhood Leukemia in Taiwan

    PubMed Central

    Chang, Wen-Shin; Ji, Hong-Xue; Hsiao, Chieh-Lun; Miao, Chia-En; Hsu, Yuan-Nian; Bau, Da-Tian

    2015-01-01

    Background Acute lymphoblastic leukemia (ALL) is the most prevalent type of pediatric cancer, the causes of which are likely to involve an interaction between genetic and environmental factors. To evaluate the effects of the genotypic polymorphisms in methylenetetrahydrofolate reductase (MTHFR) on childhood ALL risk in Taiwan, two well-known polymorphic genotypes of MTHFR, C677T (rs1801133) and A1298C (rs1801131), were analyzed to examine the extent of their associations with childhood ALL susceptibility and to discuss the MTHFR genotypic contribution to childhood ALL risk among different populations. Methodology/Principal Findings In total, 266 patients with childhood ALL and an equal number of non-cancer controls recruited were genotyped utilizing PCR-RFLP methodology. The MTHFR C677T genotype, but not the A1298C, was differently distributed between childhood ALL and control groups. The CT and TT of MTHFR C677T genotypes were significantly more frequently found in controls than in childhood ALL patients (odds ratios=0.60 and 0.48, 95% confidence intervals=0.42–0.87 and 0.24–0.97, respectively). As for gender, the boys carrying the MTHFR C677T CT or TT genotype conferred a lower odds ratio of 0.51 (95% confidence interval=0.32–0.81, P=0.0113) for childhood ALL. As for age, those equal to or greater than 3.5 years of age at onset of disease carrying the MTHFR C677T CT or TT genotype were of lower risk (odds ratio= 0.43 and 95% confidence interval=0.26–0.71, P=0.0016). Conclusions Our results indicated that the MTHFR C677T T allele was a protective biomarker for childhood ALL in Taiwan, and the association was more significant in male patients and in patients 3.5 years of age or older at onset of disease. PMID:25793509

  10. Genetic variability in the methylenetetrahydrofolate reductase gene (MTHFR) affects clinical expression of Wilson's disease.

    PubMed

    Gromadzka, Grażyna; Rudnicka, Magdalena; Chabik, Grzegorz; Przybyłkowski, Adam; Członkowska, Anna

    2011-10-01

    Wilson's disease (WND) is an autosomal recessive disorder of copper (Cu) transport, resulting from pathogenic mutations in the ATP7B gene. The reason for the high variability in phenotypic expressions of WND is unknown. Hepatotoxic and neurotoxic effects of homocysteine (Hcy), as well as interrelationships between Hcy and Cu toxicity, were documented. We genotyped the two 5,10-methylenetetrahydrofolate reductase (one of the key folate/Hcy pathway enzymes) gene (MTHFR) polymorphisms: C677T and A1298C in 245 WND patients. Next, we tested the modulation of WND phenotypes by genotypes of MTHFR. MTHFR C677T genotype distribution deviated from that expected from a population in Hardy-Weinberg equilibrium (C677T, χ(2) = 12.14, p = 0.0005). Patients with the MTHFR 1298C allele were younger at symptoms' onset than those without this allele (median (IQR) age, 24.9 (14.0) years vs. 28.5 (12.0) years, p = 0.006). Carriers of MTHFR "high activity" diplotype (double wild-type homozygotes 677CC/1298AA) manifested WND at older age, than non-carriers (median (IQR) age, 33.5 (9.0) years vs. 25.0 (13.0) years, p = 0.0009). Patients with the MTHFR 677T allele less frequently exhibited the neurological WND phenotype (31 (29.5%) vs. 36 (48.0%)), and more frequently presented with hepatic WND (44 (41.9%) vs. 22 (29.3%)), compared with subjects MTHFR 677T(-). We postulate that MTHFR polymorphism contributes to the phenotypic variability of WND. Copyright © 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  11. Genetic variants in 3′-UTRs of methylenetetrahydrofolate reductase (MTHFR) predict colorectal cancer susceptibility in Koreans

    PubMed Central

    Joo Jeon, Young; Woo Kim, Jong; Mi Park, Hye; Kim, Jung O; Geun Jang, Hyo; Oh, Jisu; Gyu Hwang, Seong; Won Kwon, Sung; Oh, Doyeun; Keun Kim, Nam

    2015-01-01

    Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) play important roles in tumor development, progression, and metastasis. Moreover, recent studies have reported that a number of 3′-UTR polymorphisms potentially bind to specific microRNAs in a variety of cancers. The aim of this study was to investigate the association of four MTHFR polymorphisms, 2572C>A [rs4846049], 4869C>G [rs1537514], 5488C>T [rs3737967], and 6685T>C [rs4846048] with colorectal cancer (CRC) in Koreans. A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of MTHFR 3′-UTR polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis or TaqMan allelic discrimination assay. We found that MTHFR 2572C>A, 4869C>G, and 5488C>T genotypes were substantially associated with CRC susceptibility. Of the potentially susceptible polymorphisms, MTHFR 2572C>A was associated with increased homocysteine and decreased folate levels in the plasma based on MTHFR 677CC. Our study provides the evidences for 3′-UTR variants in MTHFR gene as potential biomarkers for use in CRC prevention. PMID:26046315

  12. Risk of colorectal cancer associated with the C677T polymorphism in 5,10-methylenetetrahydrofolate reductase in Portuguese patients depends on the intake of methyl-donor nutrients.

    PubMed

    Guerreiro, Catarina Sousa; Carmona, Bruno; Gonçalves, Susana; Carolino, Elisabete; Fidalgo, Paulo; Brito, Miguel; Leitão, Carlos Nobre; Cravo, Marília

    2008-11-01

    Polymorphisms located in genes involved in the metabolism of folate and some methyl-related nutrients are implicated in colorectal cancer (CRC). We evaluated the association of 3 genetic polymorphisms [C677T MTHFR (methylene tetrahydrofolate reductase), A2756G MTR (methionine synthase), and C1420T SHMT (serine hydroxymethyltransferase)] with the intake of methyl-donor nutrients in CRC risk. Patients with CRC (n = 196) and healthy controls (n = 200) matched for age and sex were evaluated for intake of methyl-donor nutrients and the 3 polymorphisms. Except for folate intake, which was significantly lower in patients (P = 0.02), no differences were observed in the dietary intake of other methyl-donor nutrients between groups. High intake of folate (>406.7 microg/d) was associated with a significantly lower risk of CRC (odds ratio: 0.67; 95% CI: 0.45, 0.99). The A2756G MTR polymorphism was not associated with the risk of developing CRC. In contrast, homozygosity for the C677T MTHFR variant (TT) presented a 3.0-fold increased risk of CRC (95% CI: 1.3, 6.7). Similarly, homozygosity for the C1420T SHMT polymorphism also had a 2.6-fold increased risk (95% CI: 1.1, 5.9) of developing CRC. When interactions between variables were studied, low intake of all methyl-donor nutrients was associated with an increased risk of CRC in homozygous participants for the C677T MTHFR polymorphism, but a statistically significant interaction was only observed for folate (odds ratio: 14.0; 95% CI: 1.8, 108.5). No significant associations were seen for MTR or SHMT polymorphisms. These results show an association between the C677T MTHFR variant and different folate intakes on risk of CRC.

  13. Free-floating thrombus of the carotid artery with a homozygous methylenetetrahydrofolate reductase gene mutation: a case report.

    PubMed

    Colak, Necmettin; Nazli, Yunus; Kosehan, Dilek; Alpay, Mehmet Fatih; Cakir, Omer

    2013-02-01

    Free-floating thrombus (FFT) of the carotid artery is a rare condition of currently unknown etiology. We describe a symptomatic patient with an FFT in the left common carotid artery. A duplex ultrasonography scan showed the presence of a mobile floating thrombus moving in cyclical motion with the cardiac cycles in the left common carotid artery. During emergency surgery, an FFT was seen at this location and removed. No underlying wall defect was seen at the time of surgery. In a genetic screening test, TT homozygous for the methylenetetrahydrofolate reductase (MTHFR) C677T genetic polymorphisms was detected. The patient recovered uneventfully, with no neurogical events. Lifelong anticoagulant therapy was recommended. An aggressive surgical approach is recommended in the patient to prevent embolic episodes.

  14. Neonatal stroke associated with de novo antiphospholipid antibody and homozygous 1298C/C methylenetetrahydrofolate reductase mutation

    PubMed Central

    Rego Sousa, Paulo; Figueira, Ricardo; Vasconcellos, Rui

    2012-01-01

    Antiphospholipid antibodies are a recognised prothrombotic risk factor associated with acute ischaemic infarction. Most autoimmune diseases are rare in infants, and in the neonatal period, autoimmunity is related to transplacental passage of maternal immunoglobulin G autoantibodies. Distinguishing between de novo and acquired autoimmunity has important therapeutic implications and is crucial for determining the prognosis. We present a case of a neonatal thrombotic stroke associated with de novo synthesis of antiphospholipid antibodies, a homozygous 1298C/C methylene-tetrahydrofolate reductase mutation and a double-homozygous plasminogen activator inhibitor 1 polymorphism (PAI-1 844A/A and 675 4G/4G), which may have increased the final thrombotic risk. Her mother was not positive for antiphospholipid antibodies. The authors highlight an unequivocal evidence of a de novo case of paediatric antiphospholipid antibody syndrome and emphasise the need for a thorough investigation in cases of neonatal stroke including molecular thrombophilia study. PMID:23162020

  15. Methylenetetrahydrofolate reductase homozygous mutation in a young boy with cerebellar infarction.

    PubMed

    Spalice, Alberto; Del Balzo, Francesca; Perla, Francesco Massimo; Properzi, Enrico; Carducci, Carla; Antonozzi, Italo; Iannetti, Paola

    2009-06-08

    Posterior circulation vascular occlusive disease in children is a rare and uncommonly reported event. Among the numerous risk factors, the methylenetetrahydrofolate reductase (MTHFR) mutation is considered to be a common genetic cause of thrombosis in adults and children. Recently, a link between the MTHFR mutation and cerebrovascular disorders was reported in children. Diffusion tensor imaging (DTI) is a great improvement on magnetic resonance imaging (MRI), making the in vivo anatomical and pathological study of the brain and its fibers possible. In our patient cerebellar infarction was associated with MTHFR mutation and, in a standard neurological examination, DTI revealed normal white matter tracts.

  16. Genistein inhibits activities of methylenetetrahydrofolate reductase and lactate dehydrogenase, enzymes which use NADH as a substrate.

    PubMed

    Grabowski, Michał; Banecki, Bogdan; Kadziński, Leszek; Jakóbkiewicz-Banecka, Joanna; Kaźmierkiewicz, Rajmund; Gabig-Cimińska, Magdalena; Węgrzyn, Grzegorz; Węgrzyn, Alicja; Banecka-Majkutewicz, Zyta

    2015-09-25

    Genistein (5, 7-dihydroxy-3- (4-hydroxyphenyl)-4H-1-benzopyran-4-one) is a natural isoflavone revealing many biological activities. Thus, it is considered as a therapeutic compound in as various disorders as cancer, infections and genetic diseases. Here, we demonstrate for the first time that genistein inhibits activities of bacterial methylenetetrahydrofolate reductase (MetF) and lactate dehydrogenase (LDH). Both enzymes use NADH as a substrate, and results of biochemical as well as molecular modeling studies with MetF suggest that genistein may interfere with binding of this dinucleotide to the enzyme. These results have implications for our understanding of biological functions of genistein and its effects on cellular metabolism.

  17. A founder mutation causing a severe methylenetetrahydrofolate reductase (MTHFR) deficiency in Bukharian Jews.

    PubMed

    Ben-Shachar, Shay; Zvi, Tal; Rolfs, Arndt; Breda Klobus, Andrea; Yaron, Yuval; Bar-Shira, Anat; Orr-Urtreger, Avi

    2012-11-01

    Methylenetetrahydrofolate reductase (MTHFR) deficiency is a rare autosomal recessive disorder. A novel homozygous MTHFR c.474A>T (p.G158G) mutation was detected in two unrelated children of Jewish Bukharian origin. This mutation generates an abnormal splicing and early termination codon. A carrier frequency of 1:39 (5/196) was determined among unrelated healthy Bukharian Jews. Given the disease severity and allele frequency, a population screening for individuals of this ancestry is warranted in order to allow prenatal, or preimplantation diagnosis. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Population distribution of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C risk alleles for methotrexate toxicity in Israel.

    PubMed

    Efrati, Edna; Elkin, Hela; Nahum, Sagi; Krivoy, Norberto

    2013-04-01

    Methylenetetrahydrofolate reductase (MTHFR) is a central regulatory enzyme in the folate pathway. Two non-synonymous single nucleotide polymorphisms in MTHFR, C677T (rs1801133) and A1298C (rs1801131) have been associated with reduced MTHFR enzyme activity. These polymorphisms, especially C677T, appear to be linked with methotrexate-related toxicity, particularly hepatotoxicity; thus, pretreatment identification of individuals carrying these polymorphisms may be of clinical relevance. The purpose of this study was to determine the frequency and distribution of MTHFR polymorphic variants, known to functionally impair MTHFR activity, in the highly heterogeneous Israeli population. MTHFR genotyping was carried out in the representatives of three major demographic groups in Israel by PCR-restriction fragment length polymorphism and high-resolution melting. The relative distribution of variant alleles 677T and 1298C was found to be similar in individuals of Jewish, Druze and Arab Moslem descent (p = 0.09). However, Ashkenazi Jews displayed a 1.9-fold higher frequency of variant 677T and a 1.8-fold lower frequency of variant 1298C compared to non-Ashkenazi Jews (p < 0.001). Distinct differences in the relative frequencies of both polymorphisms were also found between Ashkenazi Jews and Druze (p < 0.01 for C677T, p < 0.01 for A1298C) or Ashkenazi Jews and Arab Moslem (p < 0.01 for C677T, p < 0.05 for A1298C). These data underscore the importance of geographic genetic analysis for a better understanding of human pharmacotherapy and personalized medicine.

  19. Alteration of the alkaloid profile in genetically modified tobacco reveals a role of methylenetetrahydrofolate reductase in nicotine N-demethylation

    USDA-ARS?s Scientific Manuscript database

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme of the tetrahydrofolate (THF)-mediated one-carbon (C1) metabolic network. This enzyme catalyzes reduction of 5,10-methylene-THF to 5-methyl-THF. The latter donates its methyl group to homocysteine forming Met, which is then used for the syn...

  20. [Posterior-predominant leukoencephalopathy which was caused by methylenetetrahydrofolate reductase deficiency and successfully treated with folic acid].

    PubMed

    Tamura, Asako; Sasaki, Ryogen; Kagawa, Ken; Nakatani, Kaname; Osaka, Hitoshi; Tomimoto, Hidekazu

    2014-01-01

    A 35-year-old woman was admitted with subacute intellectual deterioration. Laboratory studies showed elevated total homocysteine and decreased folic acid. MRI revealed leukoencephalopathy with a posterior predominance, and hyperintensity in the pyramidal tracts on T2-weighted and FLAIR images. The enzyme assay showed a deficiency of methylenetetrahydrofolate reductase (MTHFR) activity with low residual activity of 4.2% of the mean control value in cultured fibroblasts. Sequence analysis of the MTHFR gene demonstrated two homozygous missense mutations, c.677C>T (p.Ala222Val) and c.685A>C (p.Ile225Leu). c.677C>T (p.Ala222Val) is known as a common polymorphism and c.685A>C (p.Ile225Leu) is considered to be a novel polymorphism. A diagnosis of MTHFR deficiency was made. Treatment with folic acid, vitamin B12 and B6 made significant improvement of intellectual deterioration and reduction in the total homocysteine level. They also made marked resolution of leukoencephalopathy. Posterior-predominant leukoencephalopathy was found to be an excellent marker of MTHFR deficiency, and may help to establish the diagnosis.

  1. Folic acid supplementation and methylenetetrahydrofolate reductase (MTHFR) gene variations in relation to in vitro fertilization pregnancy outcome.

    PubMed

    Murto, Tiina; Kallak, Theodora K; Hoas, Annica; Altmäe, Signe; Salumets, Andres; Nilsson, Torbjörn K; Skoog Svanberg, Agneta; Wånggren, Kjell; Yngve, Agneta; Stavreus-Evers, Anneli

    2015-01-01

    To study folic acid intake, folate status and pregnancy outcome after infertility treatment in women with different infertility diagnoses in relation to methylenetetrahydrofolate reductase (MTHFR) 677C>T, 1298A>C and 1793G>A polymorphisms. Also the use of folic acid supplements, folate status and the frequency of different gene variations were studied in women undergoing infertility treatment and fertile women. Observational study. University hospital. Women undergoing infertility treatment and healthy, fertile, non-pregnant women. A questionnaire was used to assess general background data and use of dietary supplements. Blood samples were taken to determine plasma folate and homocysteine levels, and for genomic DNA extraction. A comparison of four studies was performed to assess pregnancy outcome in relation to MTHFR 677 TT vs. CC, and 1298 CC vs. AA polymorphisms. Folic acid supplement intake, and plasma folate, homocysteine and genomic assays. Women in the infertility group used significantly more folic acid supplements and had better folate status than fertile women, but pregnancy outcome after fertility treatment was not dependent on folic acid intake, folate status or MTHFR gene variations. High folic acid intakes and MTHFR gene variations seem not to be associated with helping women to achieve pregnancy during or after fertility treatment. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

  2. Heterotrimeric NADH-oxidizing methylenetetrahydrofolate reductase from the acetogenic bacterium Acetobacterium woodii.

    PubMed

    Bertsch, Johannes; Öppinger, Christian; Hess, Verena; Langer, Julian D; Müller, Volker

    2015-05-01

    The methylenetetrahydrofolate reductase (MTHFR) of acetogenic bacteria catalyzes the reduction of methylene-THF, which is highly exergonic with NADH as the reductant. Therefore, the enzyme was suggested to be involved in energy conservation by reducing ferredoxin via electron bifurcation, followed by Na(+) translocation by the Rnf complex. The enzyme was purified from Acetobacterium woodii and shown to have an unprecedented subunit composition containing the three subunits RnfC2, MetF, and MetV. The stable complex contained 2 flavin mononucleotides (FMN), 23.5 ± 1.2 Fe and 24.5 ± 1.5 S, which fits well to the predicted six [4Fe4S] clusters in MetV and RnfC2. The enzyme catalyzed NADH:methylviologen and NADH:ferricyanide oxidoreductase activity but also methylene-tetrahydrofolate (THF) reduction with NADH as the reductant. The NADH:methylene-THF reductase activity was high (248 U/mg) and not stimulated by ferredoxin. Furthermore, reduction of ferredoxin, alone or in the presence of methylene-THF and NADH, was never observed. MetF or MetVF was not able to catalyze the methylene-THF-dependent oxidation of NADH, but MetVF could reduce methylene-THF using methyl viologen as the electron donor. The purified MTHFR complex did not catalyze the reverse reaction, the endergonic oxidation of methyl-THF with NAD(+) as the acceptor, and this reaction could not be driven by reduced ferredoxin. However, addition of protein fractions made the oxidation of methyl-THF to methylene-THF coupled to NAD(+) reduction possible. Our data demonstrate that the MTHFR of A. woodii catalyzes methylene-THF reduction according to the following reaction: NADH + methylene-THF → methyl-THF + NAD(+). The differences in the subunit compositions of MTHFRs of bacteria are discussed in the light of their different functions. Energy conservation in the acetogenic bacterium Acetobacterium woodii involves ferredoxin reduction followed by a chemiosmotic mechanism involving Na(+)-translocating ferredoxin

  3. Heterotrimeric NADH-Oxidizing Methylenetetrahydrofolate Reductase from the Acetogenic Bacterium Acetobacterium woodii

    PubMed Central

    Bertsch, Johannes; Öppinger, Christian; Hess, Verena; Langer, Julian D.

    2015-01-01

    ABSTRACT The methylenetetrahydrofolate reductase (MTHFR) of acetogenic bacteria catalyzes the reduction of methylene-THF, which is highly exergonic with NADH as the reductant. Therefore, the enzyme was suggested to be involved in energy conservation by reducing ferredoxin via electron bifurcation, followed by Na+ translocation by the Rnf complex. The enzyme was purified from Acetobacterium woodii and shown to have an unprecedented subunit composition containing the three subunits RnfC2, MetF, and MetV. The stable complex contained 2 flavin mononucleotides (FMN), 23.5 ± 1.2 Fe and 24.5 ± 1.5 S, which fits well to the predicted six [4Fe4S] clusters in MetV and RnfC2. The enzyme catalyzed NADH:methylviologen and NADH:ferricyanide oxidoreductase activity but also methylene-tetrahydrofolate (THF) reduction with NADH as the reductant. The NADH:methylene-THF reductase activity was high (248 U/mg) and not stimulated by ferredoxin. Furthermore, reduction of ferredoxin, alone or in the presence of methylene-THF and NADH, was never observed. MetF or MetVF was not able to catalyze the methylene-THF-dependent oxidation of NADH, but MetVF could reduce methylene-THF using methyl viologen as the electron donor. The purified MTHFR complex did not catalyze the reverse reaction, the endergonic oxidation of methyl-THF with NAD+ as the acceptor, and this reaction could not be driven by reduced ferredoxin. However, addition of protein fractions made the oxidation of methyl-THF to methylene-THF coupled to NAD+ reduction possible. Our data demonstrate that the MTHFR of A. woodii catalyzes methylene-THF reduction according to the following reaction: NADH + methylene-THF → methyl-THF + NAD+. The differences in the subunit compositions of MTHFRs of bacteria are discussed in the light of their different functions. IMPORTANCE Energy conservation in the acetogenic bacterium Acetobacterium woodii involves ferredoxin reduction followed by a chemiosmotic mechanism involving Na

  4. Methylenetetrahydrofolate Reductase 677TT Genotype may be Associated with an Increased Lung Cancer Risk in North China: An Updated Meta

    PubMed Central

    Liu, Nan-Bo; Li, Jun; Qi, Jia-Feng; Zhang, Zhen-Zhong; Wu, Xu; Zhang, Jun-Hua

    2014-01-01

    Background Although many epidemiology studies have investigated the methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and their associations with lung cancer (LC), definite conclusions cannot be drawn. To clarify the effects of MTHFR polymorphisms on the risk of LC, we performed a meta-analysis in Chinese populations. Material/Methods Related studies were identified from PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biology Medicine (CBM) until 16 February 2014. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. Results A total of 11 studies with 2487 LC cases and 3228 controls were included in this meta-analysis. Overall, no significant association was found between MTHFR C677T polymorphism and LC risk when all studies in Chinese populations were pooled into this meta-analysis. In subgroup analyses stratified by geographical location and source of controls, significantly increased risk was found in North China (T vs. C: OR=1.28, 95% CI: 1.14–1.44; TT vs. CC: OR=1.67, 95% CI: 1.33–2.10; TT + CT vs. CC, OR=1.39, 95% CI=1.15–1.69; TT vs. CC + CT: OR=1.46, 95% CI: 1.03–2.06) and in population-based studies (TT vs. CC: OR=1.37, 95% CI: 1.14–1.65; TT vs. CC + CT: OR=1.25, 95% CI: 1.07–1.45). Conclusions This meta-analysis provides evidence that MTHFR C677T polymorphism may contribute to LC development in North China. Studies with larger sample sizes and wider spectrum of populations are warranted to verify this finding. PMID:25544260

  5. Methylenetetrahydrofolate reductase deficiency alters levels of glutamate and γ-aminobutyric acid in brain tissue.

    PubMed

    Jadavji, N M; Wieske, F; Dirnagl, U; Winter, C

    2015-06-01

    Methylenetetrahydrofolate reductase (MTHFR) is an enzyme key regulator in folate metabolism. Deficiencies in MTHFR result in increased levels of homocysteine, which leads to reduced levels of S-adenosylmethionine (SAM). In the brain, SAM donates methyl groups to catechol-O-methyltransferase (COMT), which is involved in neurotransmitter analysis. Using the MTHFR-deficient mouse model the purpose of this study was to investigate levels of monoamine neurotransmitters and amino acid levels in brain tissue. MTHFR deficiency affected levels of both glutamate and γ-aminobutyric acid in within the cerebellum and hippocampus. Mthfr (-/-) mice had reduced levels of glutamate in the amygdala and γ-aminobutyric acid in the thalamus. The excitatory mechanisms of homocysteine through activation of the N-methyl-d-aspartate receptor in brain tissue might alter levels of glutamate and γ-aminobutyric acid.

  6. Combined choroidal neovascularization and hypopituitarism in a patient with homozygous mutation in methylenetetrahydrofolate reductase gene

    PubMed Central

    Aydogdu, Aydogan; Haymana, Cem; Baskoy, Kamil; Durukan, Ali H.; Ozgur, Gokhan; Azal, Omer

    2014-01-01

    We report a case of choroidal neovascularization (CNV) secondary to methylenetetrahydrofolate reductase (MTHFR) gene mutation in a 20-year-old male patient with hypopituitarism. Treatment with three consecutive injections of intravitreal ranibizumab (anti-vascular endothelial growth factor) resulted in significant improvement of the patient's vision and the appearance of the macula. A search of the literature produced no previously reported case of MTHFR gene mutation associated both CNV and possibly hypopituitarism. With hormone replacement therapy of hypopituitarism, acetyl salicylic acid 100 mg/day also was started. The patient was clinically stable both for CNV and other thromboembolic disorders over a 6-month follow-up and also 1-year follow-up period. PMID:24672570

  7. Effect of multivitamins on plasma homocysteine in patients with the 5,10 methylenetetrahydrofolate reductase C677T homozygous state.

    PubMed

    Dell'edera, Domenico; Tinelli, Andrea; Milazzo, Giusi Natalia; Malvasi, Antonio; Domenico, Carone; Pacella, Elena; Pierluigi, Compagnoni; Giuseppe, Tarantino; Marcello, Guido; Francesco, Lomurno; Epifania, Annunziata Anna

    2013-08-01

    The role of hyperhomocysteinemia (HHcy) as a cardiovascular risk factor remains a matter of debate, while it correlates with folates, it demonstrates inverse correlation with plasma homocysteine (Hcy) levels and vitamin B12 levels and reduces plasma Hcy levels following supplementation with multivitamins. The purpose of this study was to demonstrate that administering multivitamins at specific doses for 90 days restores normal plasma Hcy levels in women who are homozygous for the thermolabile variant of 5,10 methylenetetrahydrofolate reductase (MTHFR C677T). We enrolled 106 healthy females aged between 30 and 42 years, who were non-smokers, non-vegetarian, normotensive and who had no history of food abuse in the previous months. Only females were enrolled in order to rule out any bias due to the variation in Hcy plasma concentrations between males and females. Patient blood sampling was performed in order to determine plasma Hcy, serum folic acid and vitamin B12 levels. Furthermore, molecular characterization of the C677T polymorphism present in the MTHFR gene, was also performed. The results of this study demonstrated that supplementation with specific multivitamins restores normal plasma Hcy levels, regardless of the MTHFR genotype. Furthermore, it is unnecessary to adminster high doses of folate to reduce plasma Hcy levels, and administering high doses of folate may cause pro-inflammatory and pro-proliferative effects.

  8. Seven novel mutations at the 5,10-methylenetetrahydrofolate reductase locus

    SciTech Connect

    Goyette, P.; Frosst, P.; Rosenblatt, D.S.; Rozen, R.

    1994-09-01

    5,10-methylenetetrahydrofolate reductase (MTHFR), a flavoprotein, catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a cofactor for methionine synthase in the methylation of homocysteine to methionine. Severe MTHFR deficiency, which causes homocysteinemia, is an autosomal recessive disorder with variable clinical features; developmental delay, perinatal death, mental retardation and asymptomatic individuals have been observed. A milder deficiency has been reported in patients with cardiovascular disease. We have recently described the isolation of a cDNA for MTHFR and the identification of 2 mutations in patients with severe MTHFR deficiency. We report here the characterization of 7 additional mutations at this locus: 5 missense mutations and 2 splicing mutations. Mutation analysis was performed by SSCP on PCR products generated either from reverse transcription-PCR of patients` total fibroblast RNA or from PCR of patients` genomic DNA. The 5 missense mutations are as follows: 1 Arg to Cys substitution in a hydrophilic segment proposed to be the hinge region that connects the catalytic and regulatory domains, 2 different Arg to Cys substitutions in 2 patients whose enzymatic thermolability is responsive to FAD, 1 Thr to Met substitution affecting an evolutionarily-conserved residue and a Pro to Leu substitution. The 2 splicing mutations affect the 5{prime} splice site and the 3{prime} splice site of 2 introns, respectively. The 5{prime} splice site mutation generates a 57 bp in-frame deletion of the RNA through the utilization of a cryptic 5{prime} splice site within the coding sequence. The identification of 9 mutations at this locus has allowed us to make preliminary correlations between genotype and phenotype and to contribute to a structure:function analysis of the enzyme.

  9. Plasma folate, methylenetetrahydrofolate reductase (MTHFR), and colorectal cancer risk in three large nested case-control studies.

    PubMed

    Lee, Jung Eun; Wei, Esther K; Fuchs, Charles S; Hunter, David J; Lee, I-Min; Selhub, Jacob; Stampfer, Meir J; Willett, Walter C; Ma, Jing; Giovannucci, Edward

    2012-04-01

    Few prospective studies have examined the associations between blood levels of folate, in conjunction with methylenetetrahydrofolate reductase (MTHFR) polymorphisms, and colorectal cancer. We evaluated the associations between plasma folate, MTHFR C677T, and A1298C, and colorectal cancer in three large prospective studies: the Nurses' Health Study, the Health Professionals Follow-up Study, and the Physicians' Health Study. A total of 602 incident cases were identified and individually matched to controls who provided blood specimens. We used conditional logistic regression to calculate the relative risk (RR) and 95% confidence interval (95% CI) and then pooled the estimates using a random effects model. We found a lower risk of colorectal cancer among participants with low plasma folate levels: compared with the lowest quartile, RRs (95% CIs) for each successively higher quartile of plasma folate levels were 1.55 (1.14-2.11), 1.37 (1.00-1.88), and 1.47 (1.07-2.01; P for trend = 0.10). For the MTHFR polymorphisms, RRs (95% CIs) were 0.62 (0.44-0.90) for 677TT versus CC/CT and 0.68 (0.31-1.51) for 1298CC versus AC/AA, and these lower-risk genotypes were associated with lower circulating plasma folate levels. When we partitioned the variation in plasma folate levels, variation due to folate intake was not positively associated with colorectal cancer risk. We found that low plasma folate levels were associated with lower risk of colorectal cancer. The reasons underlying a lower risk of colorectal cancer with low plasma folate levels require elucidation because plasma folate levels can reflect dietary intake, genetic influences, and other factors.

  10. [Methylenetetrahydrofolate reductase deficiency-induced schizophrenia in a school-age boy].

    PubMed

    Wang, Qiao; Liu, Jing; Liu, Yu-Peng; Li, Xi-Yuan; Ma, Yan-Yan; Wu, Tong-Fei; Ding, Yuan; Song, Jin-Qing; Wang, Yu-Jie; Yang, Yan-Ling

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) deficiency is a rare autosomal recessive disorder. It is known that MTHFR deficiency may result in hyperhomocysteinemia, but MTHFR deficiency-induced schizophrenia has been rarely reported. Here we present the clinical course, biochemical and genetic characteristics of schizophrenia resulted from MTHFR deficiency in a school-age boy. He was 13 years old. He was admitted with a two-year history of fear, auditory hallucination, learning difficulty, sleeping problems, irascibility, drowsing and giggling. At admission, he had significantly elevated plasma and urine levels of total homocysteine, significantly decreased levels of folate in serum and cerebrospinal fluid, and a normal blood concentration of methionine. Further DNA sequencing analysis showed 665C>T homozygous mutations in the MTHFR gene. The patient was diagnosed with MTHFR deficiency-associated schizophrenia and treatment with calcium folinate, vitamin B12, vitamin B6, and betaine was initiated. After the treatment for 1 week, his plasma and urine levels of homocysteine were decreased to a normal range and the clinical symptoms were significantly improved. After 3 months of treatment, the patient returned to school. He is now living with normal school life. In summary, children with late-onset MTHFR deficiency and secondary cerebral folate deficiency may lead to schizophrenia. This rare condition can be early diagnosed through analyses of blood and urine total homocysteine, amino acids in blood and folate in blood and cerebral fluid and successfully treated with folinic acid, vitamin B6, vitamin B12 and betaine.

  11. 5,10-Methylenetetrahydrofolate reductase deficiency with progressive polyneuropathy in an infant.

    PubMed

    Tsuji, Megumi; Takagi, Atsushi; Sameshima, Kiyoko; Iai, Mizue; Yamashita, Sumimasa; Shinbo, Hiroko; Furuya, Noritaka; Kurosawa, Kenji; Osaka, Hitoshi

    2011-06-01

    5,10-Methylenetetrahydrofolate reductase (MTHFR) deficiency is the most prevalent inborn error of folate metabolism, and has variable clinical manifestations from asymptomatic to severe psychomotor retardation, microcephalus and seizure. In untreated infantile cases, it predominantly affects the central nervous system, which is sometimes fatal. On the other hand, peripheral nerve involvement is uncommon. We present a severe infantile case of MTHFR deficiency that manifested unilateral phrenic nerve palsy with communicating hydrocephalus, developmental delay and died at 11months of age. An enzymatic study confirmed MTHFR deficiency with residual activity of 0.75% of mean control values in cultured fibroblasts. Mutation analysis of the MTHFR gene revealed homozygous, tandem missense mutations c.[446G>T; 447C>T] in exon 3 of the MTHFR gene converting glycine to valine (Gly149Val). In MTHFR deficiency, betaine may improve the symptoms if started immediately after birth by reducing the level of serum homocysteine and increasing that of methionine. Our results show that we should be aware of possible inborn errors of folate metabolism such as MTHFR deficiency, in infants with unexplained developmental delay manifesting rapidly progressive polyneuropathy.

  12. The C677T mutation in the methylenetetrahydrofolate reductase gene among the Indonesian Javanese population.

    PubMed

    Sadewa, Ahmad Hamim; Sunarti; Sutomo, Retno; Hayashi, Chiyo; Lee, Myeong Jin; Ayaki, Hitoshi; Sofro, Abdul Salam M; Matsuo, Masafumi; Nishio, Hisahide

    2002-12-01

    The presence of the C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene has been regarded as a genetic risk factor for coronary artery diseases and neural tube defects. Although the prevalence of this mutation has been reported from various ethnic populations, few data concerning Indonesian populations are available. We have investigated the frequency of the mutation in 68 Indonesian Javanese (residents of Java Island) and compared it with the data from 244 Japanese (residents of Honshu Island). The frequencies of the three genotypes in Javanese were C/C 0.84, C/T 0.16 and T/T 0.00, whereas those in Japanese were C/C 0.39, C/T 0.48 and T/T 0.13. The rarity of the T/T genotype in the Indonesian Javanese population may be due to malnutrition in pregnant women, because insufficient intake of folate is considered to be a survival disadvantage for fetuses with the T/T genotype. In conclusion, homozygosity for the C677T mutation in the MTHFR gene does not constitute a genetic risk factor for coronary artery diseases and neural tube defects in the Indonesian Javanese population.

  13. Prevention of brain disease from severe 5,10-methylenetetrahydrofolate reductase deficiency.

    PubMed

    Strauss, Kevin A; Morton, D Holmes; Puffenberger, Erik G; Hendrickson, Christine; Robinson, Donna L; Wagner, Conrad; Stabler, Sally P; Allen, Robert H; Chwatko, Grazyna; Jakubowski, Hieronim; Niculescu, Mihai D; Mudd, S Harvey

    2007-06-01

    Over a four-year period, we collected clinical and biochemical data from five Amish children who were homozygous for missense mutations in 5,10-methylenetetrahydrofolate reductase (MTHFR c.1129C>T). The four oldest patients had irreversible brain damage prior to diagnosis. The youngest child, diagnosed and started on betaine therapy as a newborn, is healthy at her present age of three years. We compared biochemical data among four groups: 16 control subjects, eight heterozygous parents, and five affected children (for the latter group, both before and during treatment with betaine anhydrous). Plasma amino acid concentrations were used to estimate changes in cerebral methionine uptake resulting from betaine therapy. In all affected children, treatment with betaine (534+/-222 mg/kg/day) increased plasma S-adenosylmethionine, improved markers of tissue methyltransferase activity, and resulted in a threefold increase of calculated brain methionine uptake. Betaine therapy did not normalize plasma total homocysteine, nor did it correct cerebral 5-methyltetrahydrofolate deficiency. We conclude that when the 5-methyltetrahydrofolate content of brain tissue is low, dietary betaine sufficient to increase brain methionine uptake may compensate for impaired cerebral methionine recycling. To effectively support the metabolic requirements of rapid brain growth, a large dose of betaine should be started early in life.

  14. Gene-wide association study between the methylenetetrahydrofolate reductase gene (MTHFR) and schizophrenia in the Japanese population, with an updated meta-analysis on currently available data.

    PubMed

    Yoshimi, Akira; Aleksic, Branko; Kawamura, Yukiko; Takahashi, Nagahide; Yamada, Shinnosuke; Usui, Hinako; Saito, Shinichi; Ito, Yoshihito; Iwata, Nakao; Inada, Toshiya; Noda, Yukihiro; Yamada, Kiyofumi; Ozaki, Norio

    2010-12-01

    Methylenetetrahydrofolate reductase (MTHFR) is a critical molecule for single-carbon transfer reactions. Recent evidence suggests that polymorphisms of MTHFR are related to neural tube deficits and the pathogenesis of schizophrenia. While several studies have demonstrated associations between the gene encoding the MTHFR (MTHFR) polymorphisms and schizophrenia, these studies lack consistency. Therefore, we conducted a gene-wide association study (patients with schizophrenia = 696, control subjects = 747) and performed imputation analysis. Additionally, we performed meta-analysis on currently available data from 18 studies for two common functional polymorphisms (rs1801131 and rs1801133). There were no significant associations with schizophrenia in the single marker analysis for the seven tagging SNPs of MTHFR. In the haplotypic analysis, a nominally significant association was observed between the haplotypes, which included four SNPs (rs1801133, rs17421511, rs17037396, and rs9651118) and the schizophrenic patients. Additionally, the imputation analysis demonstrated there were several associated markers on the MTHFR chromosomal region. However, confirmatory analyses of three tagging SNPs (rs1801133, rs17037396, and rs9651118) and the top SNP (rs17421511) for the imputation results (patients with schizophrenia = 797, control subjects = 1025) failed to replicate the haplotypic analysis and the imputation results. These findings suggest that MTHFR polymorphisms are unlikely to be related to the development of schizophrenia in the Japanese population. However, since our meta-analysis results demonstrated strong support for association of rs1801133 with schizophrenia, further replication studies based on a gene-wide approach need to be considered.

  15. C677T methylenetetrahydrofolate reductase and plasma homocysteine levels among Thai vegans and omnivores.

    PubMed

    Kajanachumpol, Saowanee; Atamasirikul, Kalayanee; Tantibhedhyangkul, Phieuvit

    2013-01-01

    Hyperhomocysteinemia among vegetarians and vegans is caused mostly by vitamin B12 deficiency. A C-to-T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene results in a thermolabile MTHFR, which may affect homocysteine (Hcy) levels. The importance of this gene mutation among populations depends on the T allele frequency. Blood Hcy, vitamin B12, folate, vitamin B6, and MTHFR C677T mutation status were determined in 109 vegans and 86 omnivores aged 30 - 50 years. The vegans had significantly higher Hcy levels than the omnivores, geometric means (95 % CI) 19.2 (17.0 - 21.7) µmol/L vs. 8.53 (8.12 - 8.95) µmol/L, p < 0.001. A C-to-T mutation in the vegans increased plasma Hcy, albeit insignificantly; geometric means 18.2 µmol/L, 20.4 µmol/L, and 30.0 µmol/L respectively in CC, CT, and TT MTHFR genotypes. There was also a significant decrease in serum folate; geometric means 12.1 ng/mL, 9.33 ng/mL, and 7.20 ng/mL respectively, in the CC, CT, and TT mutants, p = 0.006, and particularly, in the TT mutant compared with the CC wild type, 7.20 ng/mL vs. 12.1 ng/mL, p = 0.023. These findings were not seen in the omnivores. It was concluded that hyperhomocysteinemia is prevalent among Thai vegans due to vitamin B12 deficiency. C-to-T MTHFR mutation contributes only modestly to the hyperhomocysteinemia.

  16. Molecular characterization of five patients with homocystinuria due to severe methylenetetrahydrofolate reductase deficiency.

    PubMed

    Urreizti, R; Moya-García, A A; Pino-Ángeles, A; Cozar, M; Langkilde, A; Fanhoe, U; Esteves, C; Arribas, J; Vilaseca, M A; Pérez-Dueñas, B; Pineda, M; González, V; Artuch, R; Baldellou, A; Vilarinho, L; Fowler, B; Ribes, A; Sánchez-Jiménez, F; Grinberg, D; Balcells, S

    2010-11-01

    Methylenetetrahydrofolate reductase (MTHFR) plays a major role in folate metabolism. Disturbed function of the enzyme results in hyperhomocysteinemia and causes severe vascular and neurological disorders and developmental delay. Five patients suspected of having non-classical homocystinuria due to MTHFR deficiency were examined with respect to their symptoms, MTHFR enzyme activity and genotypes of the MTHFR gene. All patients presented symptoms of severe central nervous system disease. Two patients died, at the ages of 15 months and 14 years. One patient is currently 32 years old, and is being treated with betaine and folinic acid. The other two patients, with an early diagnosis and a severe course of the disease, are currently improving under treatment. MTHFR enzyme activity in the fibroblasts of four of the patients was practically undetectable. We found four novel mutations, three of which were missense changes c.664G> T (p.V218L), c.1316T> C (p.F435S) and c.1733T> G (p.V574G), and the fourth was the 1-bp deletion c.1780delC (p.L590CfsX72). We also found the previously reported nonsense mutation c.1420G> T (p.E470X). All the patients were homozygous. Molecular modelling of the double mutant allele (p.V218L; p.A222V) revealed that affinity for FAD was not affected in this mutant. For the p.E470X mutation, the evidence pointed to nonsense-mediated mRNA decay. In general, genotype-phenotype analysis predicts milder outcomes for patients with missense changes than for those in which mutations led to severe alterations of the MTHFR protein.

  17. Properties and Crystal Structure of Methylenetetrahydrofolate Reductase from Thermus thermophilus HB8

    PubMed Central

    Igari, Sayaka; Ohtaki, Akashi; Yamanaka, Yasuaki; Sato, Yuichi; Yohda, Masafumi; Odaka, Masafumi; Noguchi, Keiichi; Yamada, Kazuhiro

    2011-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) is one of the enzymes involved in homocysteine metabolism. Despite considerable genetic and clinical attention, the reaction mechanism and regulation of this enzyme are not fully understood because of difficult production and poor stability. While recombinant enzymes from thermophilic organisms are often stable and easy to prepare, properties of thermostable MTHFRs have not yet been reported. Methodology/Principal Findings MTHFR from Thermus thermophilus HB8, a homologue of Escherichia coli MetF, has been expressed in E. coli and purified. The purified MTHFR was chiefly obtained as a heterodimer of apo- and holo-subunits, that is, one flavin adenine dinucleotide (FAD) prosthetic group bound per dimer. The crystal structure of the holo-subunit was quite similar to the β8α8 barrel of E. coli MTHFR, while that of the apo-subunit was a previously unobserved closed form. In addition, the intersubunit interface of the dimer in the crystals was different from any of the subunit interfaces of the tetramer of E. coli MTHFR. Free FAD could be incorporated into the apo-subunit of the purified Thermus enzyme after purification, forming a homodimer of holo-subunits. Comparison of the crystal structures of the heterodimer and the homodimer revealed different intersubunit interfaces, indicating a large conformational change upon FAD binding. Most of the biochemical properties of the heterodimer and the homodimer were the same, except that the homodimer showed ≈50% activity per FAD-bound subunit in folate-dependent reactions. Conclusions/Significance The different intersubunit interfaces and rearrangement of subunits of Thermus MTHFR may be related to human enzyme properties, such as the allosteric regulation by S-adenosylmethionine and the enhanced instability of the Ala222Val mutant upon loss of FAD. Whereas E. coli MTHFR was the only structural model for human MTHFR to date, our findings suggest that Thermus MTHFR will

  18. Methylenetetrahydrofolate reductase C677T and glutathione S-transferase P1 A313G are associated with a reduced risk of preeclampsia in Maya-Mestizo women.

    PubMed

    Canto, Patricia; Canto-Cetina, Thelma; Juárez-Velázquez, Rocio; Rosas-Vargas, Haydee; Rangel-Villalobos, Héctor; Canizales-Quinteros, Samuel; Velázquez-Wong, Ana C; Villarreal-Molina, María T; Fernández, Genny; Coral-Vázquez, Ramón

    2008-05-01

    Preeclampsia, a common complication of pregnancy, is characterized by elevated blood pressure and proteinuria developing after 20 weeks' gestational age. Susceptibility to this syndrome is believed to have a genetic component. The aim of this study was to investigate whether or not the 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T and glutathione S-transferase P1 (GSTP1) A313G polymorphisms are associated with preeclampsia in Maya-Mestizo women. A case-control study was performed, in which 125 preeclamptic patients and 274 healthy controls were genotyped for the MTHFR C677T and GSTP1 A313G polymorphisms by real-time PCR allelic discrimination. Allele and genotype frequencies were compared using the chi2 tests. The MTHFR 677T allele and the 677TT genotype were significantly more frequent in the controls, suggesting an association with a decreased risk of preeclampsia (p = 0.017 and p = 0.007, respectively). Similarly, GSTP1 313GG/GC genotypes and the G allele were more frequent in controls, showing a significant association with reduced risk of preeclampsia (p = 0.008 and p = 0.013, respectively). Our results suggest, for the first time, that the MTHFR 677T and GSTP1 313G polymorphisms confer a significantly decreased risk of developing preeclampsia in the Mexican Maya-Mestizo population.

  19. Common 677C-->T mutation of the 5,10-methylenetetrahydrofolate reductase gene affects follicular estradiol synthesis.

    PubMed

    Hecht, Stephanie; Pavlik, Roman; Lohse, Peter; Noss, Ulrich; Friese, Klaus; Thaler, Christian J

    2009-01-01

    To investigate the influence of the 5,10-methylenetetrahydrofolate reductase 677C-->T mutation on the E(2) synthesis in human granulosa cells (GCs). In vitro cell culture study. Research laboratory of a university hospital. Follicular fluids (n = 139) and GCs (n = 66) were obtained from patients undergoing controlled ovarian hyperstimulation for IVF with or without ICSI. Granulosa cells were cultured for a total of 5 days. On day 3, the cells either were stimulated with recombinant (r-) FSH or r-LH (80 IU/L for 48 h) or were sham stimulated. Estradiol and protein content were measured in the pooled follicular fluids of each individual. At the end of each GC-culturing period, the concentrations of E(2) were measured in the supernatants of triplicate cultures by immunoassays. The 5,10-methylenetetrahydrofolate reductase 677C-->T genotype was determined by RFLP analysis. The E(2)-protein ratio of homozygous T/T carriers was significantly lower compared with that of homozygous C/C individuals. Furthermore, basal and r-FSH- as well as r-LH-stimulated E(2) synthesis of GC obtained from homozygous T/T patients was significantly reduced, compared with GC from heterozygous C/T and homozygous C/C subjects. Decreased E(2) in follicular fluid and decreased E(2) synthesis of GC from homozygous T/T individuals suggest that reduced follicular E(2) is a result of impaired E(2) production of human GC.

  20. Genotype prevalence and allele frequencies of 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T mutation in two caste groups of India.

    PubMed

    Rai, V; Yadav, U; Kumar, P

    2012-06-15

    The aim of the present study was to investigate the distribution of 5,10-methylenetetrahydrofolate reductase (MTHFR) polymorphism in two caste group populations of eastern Uttar Pradesh. This mutation has been suggested to be positively associated with the risk of several congenital and multifactorial disorders. Frequency of mutant T allele differs in various ethnic and geographical populations of the world. MTHFR C677T mutation analysis was carried out by PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism) method and the samples studied were randomly selected from the healthy individuals belonging to two caste populations. In Brahmin samples, genotype frequencies of CC, CT and TT were 0.727, 0.25 and 0.023 respectively whereas in Rajput samples, CC genotype was observed in 88 samples, CT genotype in 25 and TT genotype was found in 2 samples. Frequency of mutant T allele was found to be 0.147 in Brahmin and 0.126 in Rajput populations. The percentage of CT genotype and C allele were high in both the populations.

  1. Insights into severe 5,10-methylenetetrahydrofolate reductase deficiency: molecular genetic and enzymatic characterization of 76 patients.

    PubMed

    Burda, Patricie; Schäfer, Alexandra; Suormala, Terttu; Rummel, Till; Bürer, Céline; Heuberger, Dorothea; Frapolli, Michele; Giunta, Cecilia; Sokolová, Jitka; Vlášková, Hana; Kožich, Viktor; Koch, Hans Georg; Fowler, Brian; Froese, D Sean; Baumgartner, Matthias R

    2015-06-01

    5,10-Methylenetetrahydrofolate reductase (MTHFR) deficiency is the most common inherited disorder of folate metabolism and causes severe hyperhomocysteinaemia. To better understand the relationship between mutation and function, we performed molecular genetic analysis of 76 MTHFR deficient patients, followed by extensive enzymatic characterization of fibroblasts from 72 of these. A deleterious mutation was detected on each of the 152 patient alleles, with one allele harboring two mutations. Sixty five different mutations (42 novel) were detected, including a common splicing mutation (c.1542G>A) found in 21 alleles. Using an enzyme assay in the physiological direction, we found residual activity (1.7%-42% of control) in 42 cell lines, of which 28 showed reduced affinity for nicotinamide adenine dinucleotide phosphate (NADPH), one reduced affinity for methylenetetrahydrofolate, five flavin adenine dinucleotide-responsiveness, and 24 abnormal kinetics of S-adenosylmethionine inhibition. Missense mutations causing virtually absent activity were found exclusively in the N-terminal catalytic domain, whereas missense mutations in the C-terminal regulatory domain caused decreased NADPH binding and disturbed inhibition by S-adenosylmethionine. Characterization of patients in this way provides a basis for improved diagnosis using expanded enzymatic criteria, increases understanding of the molecular basis of MTHFR dysfunction, and points to the possible role of cofactor or substrate in the treatment of patients with specific mutations.

  2. Acute renal infarction associated with homozygous methylenetetrahydrofolate reductase mutation C677T and IgA beta-2-glycoprotein antibodies.

    PubMed

    Vlachostergios, Panagiotis J; Dufresne, François

    2015-07-01

    Arterial thrombosis of the kidney(s) is a rare clinical entity usually presenting as a result of cardioembolic disease, though rare inherited hypercoagulable states have also been implicated. Within this context, both hyperhomocysteinemia triggered by a mutated methylenetetrahydrofolate reductase (MTHFR) gene product and the presence of antiphospholipid antibodies have been separately associated with arterial thrombotic events, including renal artery embolism. We present a case of combined homozygous MTHFR C677T mutation and IgA beta-2-glycoprotein antibody positivity resulting in acute renal infarction and previous silent myocardial infarction. An acute and otherwise unexplained thrombotic event of unusual location always warrants further investigation, which should include testing for hereditary thrombophilic disorders.

  3. Mutations in cystathionine beta-synthase or methylenetetrahydrofolate reductase gene increase N-homocysteinylated protein levels in humans.

    PubMed

    Jakubowski, Hieronim; Boers, Godfried H J; Strauss, Kevin A

    2008-12-01

    Severely elevated plasma homocysteine (Hcy) levels observed in genetic disorders of Hcy metabolism are associated with pathologies in multiple organs and lead to premature death due to vascular complications. In addition to elevating plasma Hcy, mutations in cystathionine beta-synthase (CBS) or methylenetetrahydrofolate reductase (MTHFR) gene lead to markedly elevated levels of circulating Hcy-thiolactone. The thiooester chemistry of Hcy-thiolactone underlies its ability to form isopeptide bonds with protein lysine residues (N-Hcy-protein), which may impair or alter the protein's function. However, it was not known whether genetic deficiencies in Hcy metabolism affect N-Hcy-protein levels in humans. Here we show that plasma N-Hcy-protein levels are significantly elevated in CBS- and MTHFR-deficient patients. We also show that CBS-deficient patients have significantly elevated plasma levels of prothrombotic N-Hcy-fibrinogen. These results provide a possible explanation for increased atherothrombosis observed in CBS-deficient patients.

  4. Genetic determinants of hyperhomocysteinaemia: the roles of cystathionine beta-synthase and 5,10-methylenetetrahydrofolate reductase.

    PubMed

    Blom, H J

    2000-12-01

    Over the last decade mild hyperhomocysteinaemia has widely been recognised as a new risk factor for arteriosclerosis and thrombosis. Main regulating enzymes of homocysteine (Hcy) metabolism are cystathionine beta-synthase (CBS), methionine synthase and methylenetetrahydrofolate reductase (MTHFR). Early studies on patients with vascular disease described elevated Hcy concentrations after methionine loading and decreased CBS activity, resembling heterozygotes for CBS deficiency. Therefore, heterozygosity for CBS deficiency was proposed as the main cause of mild hyperhomocysteinaemia. However, more recent enzymatic and molecular genetic studies have demonstrated that heterozygosity for CBS deficiency is not or only a very minor cause of mild hyperhomocysteinaemia in vascular disease. We discovered two common genetic causes of mild hyperhomocysteinaemia, the 677C > T and the 1298A > C mutations in the coding region of MTHFR. The 677C > T mutation causes reduced enzyme activity with thermolabile protein properties, elevated Hcy and low-normal or decreased plasma folate levels. The 1298A > C mutation relates also to decreased enzyme activity, but not to thermolabile protein, and Hcy and folate levels are not influenced. However, compound heterozygosity for these two mutations, i.e. individuals with the 677CT/1298AC genotype, have elevated Hcy and decreased plasma folate levels. Gene-enviroment interactions between 677C > T and folate is demonstrated in individuals with the 677TT genotype. Those with low-normal folate have elevated Hcy, whereas those with high-normal folate have normal Hcy concentrations. The elevated Hcy levels due to these mutations can be normalised by administration of folate, but whether folate reduces the risk of cardiovascular disease remains to be established. Heterozygosity for cystathionine beta-synthase deficiency is a minor cause of hyperhomocysteinaemia. The current data on mutations in the methylenetetrahydrofolate reductase gene do not tell

  5. Methylenetetrahydrofolate reductase gene germ-line C677T and A1298C SNPs are associated with colorectal cancer risk in the Turkish population.

    PubMed

    Ozen, Filiz; Sen, Metin; Ozdemir, Ozturk

    2014-01-01

    Colorectal cancer (CRC) is the third most common cause of death due to cancer in the worldwide and the incidence is also increasing in Turkey. Our present aim was to investigate any association between germ-line methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and CRC risk in Turkey. A total of 86 CRC cases and 212 control individuals of the same ethnicity were included in the current study. Peripheral blood-DNA samples were used for genotyping by StripAssay technique, based on the reverse- hybridization principle and real-time PCR methods. Results were compared in Pearson Chi-square and multiple logistic regression models. The MTHFR 677TT (homozygous) genotype was found in 20.9% and the T allele frequency 4.2-fold increased in CRC when compared with the control group.The second SNP MTHFR 1298CC (homozygous) genotype was found in 14.0% and the C allele frequency 1.4-fold elevated in the CRC group. The current data suggest strong associations between both SNPs of germ-line MTHFR 677 C>T and 1298 A>C genotypes and CRC susceptibility in the Turkish population. Now the results need to be confirmed with a larger sample size.

  6. Methylenetetrahydrofolate reductase (MTHFR) genetic variation and major depressive disorder prognosis: A five-year prospective cohort study of primary care attendees.

    PubMed

    Bousman, Chad A; Potiriadis, Maria; Everall, Ian P; Gunn, Jane M

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) genetic variation has been associated with the diagnosis of major depressive disorder (MDD) but no study to date has examined the effect MTHFR variation has on MDD prognosis. We sought to examine the prospective effects of two common MTHFR variants (C677T and A1298C) as well as seven haplotype-tagging single nucleotide polymorphisms (htSNPs) on MDD prognosis over a 5-year (60-month) period. Participants were 147 depressed primary care attendees enrolled in the Diagnosis, Management and Outcomes of Depression in Primary Care (diamond) prospective cohort study. Prognosis of MDD was measured using three methods: (1) DSM-IV criteria, (2) Primary Care Evaluation of Mental Disorders Patient Health Questionnaire-9 (PHQ-9), and (3) Center for Epidemiologic Studies Depression Scale (CESD). DSM-IV criteria for MDD was assessed using the Composite International Diagnostic Interview at baseline and 24, 36, 48, and 60 months post-baseline; whereas, PHQ-9 and CESD measures were employed at baseline and 12, 24, 36, 48, and 60 months post-baseline. Repeated measures analysis of variance showed that PHQ-9 symptom severity trajectories differed by C677T genotype (F = 3.34, df = 2,144, P = 0.038), with 677CC genotype showing the most severe symptom severity course over the 60 months of observation. Neither the A1298C polymorphism nor any of the htSNPs were associated with MDD prognosis regardless of measure used. Our results suggest that the MTHFR C677T polymorphism may serve as a marker for MDD prognosis pending independent replication. © 2013 Wiley Periodicals, Inc.

  7. Meta-analysis of Methylenetetrahydrofolate reductase maternal gene in Down syndrome: increased susceptibility in women carriers of the MTHFR 677T allele.

    PubMed

    Victorino, D B; Godoy, M F; Goloni-Bertollo, E M; Pavarino, E C

    2014-08-01

    Because a number of data studies include some controversial results about Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and Down syndrome (DS), we performed a meta-analysis to determine a more precise estimation of this association. Studies were searched on PubMed, EMBASE and Lilacs-Scielo, up to April 2013, and they were eligible if they included case mothers (DSM) that have gave birth to children with DS, and controls mothers (CM) that have gave birth to healthy children without chromosomal abnormality, syndrome or malformation. The combined odds ratio with 95% confidence intervals was calculated by fixed or random effects models to assess the strength of associations. Potential sources of heterogeneity between studies were evaluated using Q test and the I(2). Publication bias was estimated using Begg's test and Egger's linear regression test. Sensitivity analyses were performed by using allelic, dominant, recessive and codominant genetic models, Hardy-Weinberg equilibrium (HWE) and ethnicity. Twenty-two studies with 2,223 DSM and 2,807 CM were included for MTHFR C677T and 15 studies with 1,601 DSM and 1,849 CM were included for MTHFR A1298C. Overall analysis suggests an association of the MTHFR C677T polymorphism with maternal risk for DS. Moreover, no association between the MTHFR A1298C polymorphism and maternal risk for DS was found. There is also evidence of higher heterogeneity, with I(2) test values ranging from 8 to 89%. No evidence of publication bias was found. Taken together, our meta-analysis implied that the T allele carriers might carry an increased maternal risk for DS.

  8. Life-threatening methylenetetrahydrofolate reductase (MTHFR) deficiency with extremely early onset: characterization of two novel mutations in compound heterozygous patients.

    PubMed

    Forges, Thierry; Chery, Céline; Audonnet, Sandra; Feillet, François; Gueant, Jean-Louis

    2010-06-01

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzymatic component of the folate cycle, converting 5,10-methylenetetrahydrofolate into 5-methyltetrahydrofolate, the methyl donor for remethylation of homocysteine into methionine. Severe MTHFR deficiency is a rare recessive disease leading to major hyperhomocysteinemia, homocystinuria, and progressive neurological distress within the two first decades of life. More than 50 mutations have been reported so far in affected patients but only a few cases with very early onset of symptoms during the first weeks have been described, most of them showing a particular severe clinical course. We detected two novel mutations by direct sequencing of MTHFR in compound heterozygous patients with extremely low or undetectable enzyme activity; one of them had clinical onset during the first week of life and fatal issue at the age of six weeks. Prenatal diagnosis of his sibling allowed for early treatment with B vitamins and betaine and a favorable outcome. One of these mutations (c.523G>A) led to an Ala>Thr transition in the catalytic domain of the enzyme, the other (c.1166G>A) induced alternative splicing of exon 7 at the junction of the catalytic and regulatory domains. Both parents carried only one of these mutations and presented with moderate and intermediate hyperhomocysteinemia, respectively, without neurological symptoms. Severe MTHFR deficiency thus has to be taken into consideration when investigating neurological distress even in the newborn, regarding the need for an earliest possible treatment. Characterization of the relatives further allows for preventive measure to limit the risks of chronic hyperhomocysteinemia.

  9. Association of Methylenetetrahydrafolate Reductase Gene Polymorphism (MTHFR) in Patients with Gallbladder Cancer.

    PubMed

    Dixit, Ruhi; Singh, Gyanendra; Pandey, Manoj; Basu, Somprakas; Bhartiya, Satyanam Kumar; Singh, K K; Shukla, Vijay Kumar

    2016-03-01

    5,10-Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in folate metabolism and plays a major role in DNA methylation. There are two popular MTHFR polymorphisms known as C677T and A1298C which are found to be involved in folate metabolism and lowering the enzyme activity, thus may be linked with cancer development. This study aims to look at the association of these polymorphisms in gallbladder cancer. Thirty patients each with gallbladder cancer, cholelithiasis, and normal gallbladder were genotyped for the above-given polymorphisms by PCR-restriction fragment length polymorphism (RFLP) method. C677T MTHFR polymorphism was not associated (χ(2) = 2.44, p = 0.85) with an increased likelihood of having gallbladder cancer. A1298C was significantly associated (χ(2) = 28.87, p < 0.001) with risk of developing gallbladder cancer. A1298C was significantly correlated with grade (r = 0.337, p < 0.001) and histopathology (r = 0.446, p < 0.001). This study proposed that MTHFR A1298C polymorphism may be associated with risk of developing gallbladder cancer, and there is no association between C677T polymorphism and gallbladder cancer.

  10. Association between methionine synthase reductase A66G polymorphism and primary infertility in Chinese males.

    PubMed

    Li, X Y; Ye, J Z; Ding, X P; Zhang, X H; Ma, T J; Zhong, R; Ren, H Y

    2015-04-15

    We examined the association between the methionine synthase reductase (MTRR A66G), methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), and methionine synthase (MS A2756G) genotypes and non-obstructive male infertility in a Chinese population. This case-control study included 162 infertile Chinese patients with azoospermia (N = 100) or oligoasthenozoospermia (N = 62) and 120 fertile men as controls. The polymorphisms MTRR A66G, MTHFR C677T, A1298C, and MS A2756G were identified by direct DNA sequencing and the results were statistically analyzed. We found no association between the incidence of any of these variants in azoospermia patients and control populations. The frequency of the MTRR66 polymorphic genotypes (AG, AG+GG) was significantly higher in the oligoasthenozoospermia group compared to the controls (P = 0.013, 0.012). Our findings revealed an association between the single-nucleotide polymorphism A66G in the MTRR gene and male infertility, particularly in oligoasthenozoospermia males, suggesting that this polymorphism is a genetic risk factor for male infertility in Chinese men.

  11. The maize brown midrib2 (bm2) gene encodes a methylenetetrahydrofolate reductase that contributes to lignin accumulation.

    PubMed

    Tang, Ho Man; Liu, Sanzhen; Hill-Skinner, Sarah; Wu, Wei; Reed, Danielle; Yeh, Cheng-Ting; Nettleton, Dan; Schnable, Patrick S

    2014-02-01

    The midribs of maize brown midrib (bm) mutants exhibit a reddish-brown color associated with reductions in lignin concentration and alterations in lignin composition. Here, we report the mapping, cloning, and functional and biochemical analyses of the bm2 gene. The bm2 gene was mapped to a small region of chromosome 1 that contains a putative methylenetetrahydrofolate reductase (MTHFR) gene, which is down-regulated in bm2 mutant plants. Analyses of multiple Mu-induced bm2-Mu mutant alleles confirmed that this constitutively expressed gene is bm2. Yeast complementation experiments and a previously published biochemical characterization show that the bm2 gene encodes a functional MTHFR. Quantitative RT-PCR analyses demonstrated that the bm2 mutants accumulate substantially reduced levels of bm2 transcript. Alteration of MTHFR function is expected to influence accumulation of the methyl donor S-adenosyl-L-methionine (SAM). Because SAM is consumed by two methyltransferases in the lignin pathway (Ye et al., ), the finding that bm2 encodes a functional MTHFR is consistent with its lignin phenotype. Consistent with this functional assignment of bm2, the expression patterns of genes in a variety of SAM-dependent or -related pathways, including lignin biosynthesis, are altered in the bm2 mutant. Biochemical assays confirmed that bm2 mutants accumulate reduced levels of lignin with altered composition compared to wild-type. Hence, this study demonstrates a role for MTHFR in lignin biosynthesis.

  12. Mutations in methylenetetrahydrofolate reductase and in cysthationine beta synthase: is there a link to homocysteine levels in peripheral arterial disease?

    PubMed

    Santos, Maria E R C; das C L E Silva, Francisco; Gomes, Karina B; Fernandes, Ana Paula M; Freitas, Fernanda R; Faria, Mayara C; Mota, Ana Paula L; Carvalho, Maria G

    2011-06-01

    Peripheral arterial disease (PAD) is an atherosclerotic disturbance characterized by a progressive obstruction of lower limb arteries. Many risk factors associated with PAD development have being reported in the literature. The present study aimed to investigate whether mutations in the methylenetetrahydrofolate reductase (MTHFR) or in the cystathionine beta synthase (CBS) genes are associated with higher levels of homocysteine and the risk of PAD in patients from Brazil. This study analyzed 39 patients with PAD and 32 without PAD in whom risk factors and C677T mutations in the MTHFR gene and both 844ins68 and T833C mutations in the CBS gene were investigated. Although higher levels of homocysteine could be observed in patients with PAD compared to controls, no association between the increase of homocysteine and the frequency of C677T, 844ins68, and T833C mutations could be observed. The results suggest that these mutations do not appear to be related to either homocysteine levels or the development of the disease. However, hyperhomocysteinemia and smoking are important factors in PAD development.

  13. The MET13 methylenetetrahydrofolate reductase gene is essential for infection-related morphogenesis in the rice blast fungus Magnaporthe oryzae.

    PubMed

    Yan, Xia; Que, Yawei; Wang, Hong; Wang, Congcong; Li, Ya; Yue, Xiaofeng; Ma, Zhonghua; Talbot, Nicholas J; Wang, Zhengyi

    2013-01-01

    Methylenetetrahydrofolate reductases (MTHFRs) play a key role in the biosynthesis of methionine in both prokaryotic and eukaryotic organisms. In this study, we report the identification of a novel T-DNA-tagged mutant WH672 in the rice blast fungus Magnaporthe oryzae, which was defective in vegetative growth, conidiation and pathogenicity. Analysis of the mutation confirmed a single T-DNA insertion upstream of MET13, which encodes a 626-amino-acid protein encoding a MTHFR. Targeted gene deletion of MET13 resulted in mutants that were non-pathogenic and significantly impaired in aerial growth and melanin pigmentation. All phenotypes associated with Δmet13 mutants could be overcome by addition of exogenous methionine. The M. oryzae genome contains a second predicted MTHFR-encoding gene, MET12. The deduced amino acid sequences of Met13 and Met12 share 32% identity. Interestingly, Δmet12 mutants produced significantly less conidia compared with the isogenic wild-type strain and grew very poorly in the absence of methionine, but were fully pathogenic. Deletion of both genes resulted in Δmet13Δmet12 mutants that showed similar phenotypes to single Δmet13 mutants. Taken together, we conclude that the MTHFR gene, MET13, is essential for infection-related morphogenesis by the rice blast fungus M. oryzae.

  14. Positional cloning in Cryptococcus neoformans and its application for identification and cloning of the gene encoding methylenetetrahydrofolate reductase.

    PubMed

    Toh-E, Akio; Ohkusu, Misako; Shimizu, Kiminori; Kawamoto, Susumu

    2015-03-01

    Cryptococcus neoformans, a basidiomycetous human pathogenic yeast, has been widely used in research fields in medical mycology as well as basic biology. Gene cloning or identification of the gene responsible for a mutation of interest is a key step for functional analysis of a particular gene. The availability therefore, of the multiple methods for cloning is desirable. In this study, we proposed a method for a mapping-based gene identification/cloning (positional cloning) method in C. neoformans. To this end, we constructed a series of tester strains, one of whose chromosomes was labeled with the URA5 gene. A heterozygous diploid constructed by crossing one of the tester strains to a mutant strain of interest loses a chromosome(s) spontaneously, which is the basis for assigning a recessive mutant gene to a particular chromosome in the mitotic mapping method. Once the gene of interest is mapped to one of the 14 chromosomes, classical genetic crosses can then be performed to determine its more precise location. The positional information thus obtained can then be used to significantly narrow down candidate genes by referring to the Cryptococcus genome database. Each candidate gene is then examined whether it would complement the mutation. We successfully applied this method to identify CNA07390 encoding methylenetetrahydrofolate reductase as the gene responsible for a methionine-requiring mutant in our mutant collection.

  15. The methylenetetrahydrofolate reductase C677T genotype and the risk of obesity in three large population-based cohorts.

    PubMed

    Lewis, Sarah J; Lawlor, Debbie A; Nordestgaard, Børge G; Tybjaerg-Hansen, Anne; Ebrahim, Shah; Zacho, Jeppe; Ness, Andy; Leary, Sam; Smith, George Davey

    2008-07-01

    Epidemiological studies have shown that low folate levels are associated with a high body mass index (BMI). These findings have potentially important health implications and warrant further investigation to determine whether a causal relationship exists and the direction of this relationship. The methylenetetrahydrofolate reductase (MTHFR) C677T TT genotype is associated with reduced folate availability and may be a surrogate for measuring folate levels. We sought to determine whether MTHFR C677T genotype was associated with obesity. We carried out our study on four populations from three longitudinal studies based in the UK and Denmark in which DNA for genotyping was obtained along with measures of obesity. Our subjects were taken from the British Women's Heart and Health Study (BWHHS), the Avon Longitudinal Study of Parents and Children (two populations: mothers and children) and the Copenhagen City Heart Study. We performed analyses separately by population, and then carried out a meta-analysis, combining similar populations. Initial findings in the BWHHS suggested that the TT genotype may be associated with an increased risk of obesity BMI > or =30, however, no association was found with BMI or central adiposity in this cohort. This genotype was not associated with obesity in our other cohorts. Our results suggest that the initial positive finding with obesity in the BWHHS was a chance finding. Our findings do not support a causal effect of low folate on obesity.

  16. Moderately elevated plasma homocysteine, methylenetetrahydrofolate reductase genotype, and risk for stroke, vascular dementia, and Alzheimer disease in Northern Ireland.

    PubMed

    McIlroy, Stephen P; Dynan, Kevin B; Lawson, John T; Patterson, Christopher C; Passmore, A Peter

    2002-10-01

    Elevated plasma homocysteine level has been associated with increased risk for cardiovascular and cerebrovascular disease. Variation in the levels of this amino acid has been shown to be due to nutritional status and methylenetetrahydrofolate reductase (MTHFR) genotype. Under a case-control design we compared fasting levels of homocysteine and MTHFR genotypes in groups of subjects consisting of stroke, vascular dementia (VaD), and Alzheimer disease patients and normal controls from Northern Ireland. A significant increase in plasma homocysteine was observed in all 3 disease groups compared with controls. This remained significant after allowance for confounding factors (age, sex, hypertension, cholesterol, smoking, creatinine, and nutritional measures). MTHFR genotype was not found to influence homocysteine levels, although the T allele was found to increase risk for VaD and perhaps dementia after stroke. We report that moderately high plasma levels of homocysteine are associated with stroke, VaD, and Alzheimer disease. This is not due to vascular risk factors, nutritional status, or MTHFR genotype.

  17. Alteration of the alkaloid profile in genetically modified tobacco reveals a role of methylenetetrahydrofolate reductase in nicotine N-demethylation.

    PubMed

    Hung, Chiu-Yueh; Fan, Longjiang; Kittur, Farooqahmed S; Sun, Kehan; Qiu, Jie; Tang, She; Holliday, Bronwyn M; Xiao, Bingguang; Burkey, Kent O; Bush, Lowell P; Conkling, Mark A; Roje, Sanja; Xie, Jiahua

    2013-02-01

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme of the tetrahydrofolate (THF)-mediated one-carbon (C1) metabolic network. This enzyme catalyzes the reduction of 5,10-methylene-THF to 5-methyl-THF. The latter donates its methyl group to homocysteine, forming methionine, which is then used for the synthesis of S-adenosyl-methionine, a universal methyl donor for numerous methylation reactions, to produce primary and secondary metabolites. Here, we demonstrate that manipulating tobacco (Nicotiana tabacum) MTHFR gene (NtMTHFR1) expression dramatically alters the alkaloid profile in transgenic tobacco plants by negatively regulating the expression of a secondary metabolic pathway nicotine N-demethylase gene, CYP82E4. Quantitative real-time polymerase chain reaction and alkaloid analyses revealed that reducing NtMTHFR expression by RNA interference dramatically induced CYP82E4 expression, resulting in higher nicotine-to-nornicotine conversion rates. Conversely, overexpressing NtMTHFR1 suppressed CYP82E4 expression, leading to lower nicotine-to-nornicotine conversion rates. However, the reduced expression of NtMTHFR did not affect the methionine and S-adenosyl-methionine levels in the knockdown lines. Our finding reveals a new regulatory role of NtMTHFR1 in nicotine N-demethylation and suggests that the negative regulation of CYP82E4 expression may serve to recruit methyl groups from nicotine into the C1 pool under C1-deficient conditions.

  18. The MET13 Methylenetetrahydrofolate Reductase Gene Is Essential for Infection-Related Morphogenesis in the Rice Blast Fungus Magnaporthe oryzae

    PubMed Central

    Wang, Hong; Wang, Congcong; Li, Ya; Yue, Xiaofeng; Ma, Zhonghua; Talbot, Nicholas J.; Wang, Zhengyi

    2013-01-01

    Methylenetetrahydrofolate reductases (MTHFRs) play a key role in the biosynthesis of methionine in both prokaryotic and eukaryotic organisms. In this study, we report the identification of a novel T-DNA-tagged mutant WH672 in the rice blast fungus Magnaporthe oryzae, which was defective in vegetative growth, conidiation and pathogenicity. Analysis of the mutation confirmed a single T-DNA insertion upstream of MET13, which encodes a 626-amino-acid protein encoding a MTHFR. Targeted gene deletion of MET13 resulted in mutants that were non-pathogenic and significantly impaired in aerial growth and melanin pigmentation. All phenotypes associated with Δmet13 mutants could be overcome by addition of exogenous methionine. The M. oryzae genome contains a second predicted MTHFR-encoding gene, MET12. The deduced amino acid sequences of Met13 and Met12 share 32% identity. Interestingly, Δmet12 mutants produced significantly less conidia compared with the isogenic wild-type strain and grew very poorly in the absence of methionine, but were fully pathogenic. Deletion of both genes resulted in Δmet13Δmet12 mutants that showed similar phenotypes to single Δmet13 mutants. Taken together, we conclude that the MTHFR gene, MET13, is essential for infection-related morphogenesis by the rice blast fungus M. oryzae. PMID:24116181

  19. Severe methylenetetrahydrofolate reductase deficiency: clinical clues to a potentially treatable cause of adult-onset hereditary spastic paraplegia.

    PubMed

    Lossos, Alexander; Teltsh, Omri; Milman, Tsipi; Meiner, Vardiella; Rozen, Rima; Leclerc, Daniel; Schwahn, Bernd C; Karp, Natalya; Rosenblatt, David S; Watkins, David; Shaag, Avraham; Korman, Stanley H; Heyman, Samuel N; Gal, Aya; Newman, J P; Steiner-Birmanns, Bettina; Abramsky, Oded; Kohn, Yoav

    2014-07-01

    Hereditary spastic paraplegia is a highly heterogeneous group of neurogenetic disorders with pure and complicated clinical phenotypes. No treatment is available for these disorders. We identified 2 unrelated families, each with 2 siblings with severe methylenetetrahydrofolate reductase (MTHFR) deficiency manifesting a complicated form of adult-onset hereditary spastic paraparesis partially responsive to betaine therapy. Both pairs of siblings presented with a similar combination of progressive spastic paraparesis and polyneuropathy, variably associated with behavioral changes, cognitive impairment, psychosis, seizures, and leukoencephalopathy, beginning between the ages of 29 and 50 years. By the time of diagnosis a decade later, 3 patients were ambulatory and 1 was bedridden. Investigations have revealed severe hyperhomocysteinemia and hypomethioninemia, reduced fibroblast MTHFR enzymatic activity (18%-52% of control participants), and 3 novel pathogenic MTHFR mutations, 2 as compound heterozygotes in one family and 1 as a homozygous mutation in the other family. Treatment with betaine produced a rapid decline of homocysteine by 50% to 70% in all 4 patients and, over 9 to 15 years, improved the conditions of the 3 ambulatory patients. Although severe MTHFR deficiency is a rare cause of complicated spastic paraparesis in adults, it should be considered in select patients because of the potential therapeutic benefit of betaine supplementation.

  20. Rapidly progressive psychotic symptoms triggered by infection in a patient with methylenetetrahydrofolate reductase deficiency: a case report.

    PubMed

    Iida, Shin; Nakamura, Masataka; Asayama, Shinya; Kunieda, Takenobu; Kaneko, Satoshi; Osaka, Hitoshi; Kusaka, Hirofumi

    2017-02-28

    Methylenetetrahydrofolate reductase (MTHFR) deficiency is a rare inborn error of metabolism inherited in autosomal recessive pattern and is associated with a wide spectrum of neurological abnormalities. We herein describe a 15-year-old boy with MTHFR deficiency who presented with a slowly progressive decline of school performance and a spastic gait. Rapidly deteriorating psychosis and repetitive seizures triggered by a febrile infection prompted neurological investigation. He had significantly elevated total plasma homocysteine and urinary homocystine levels, as well as a decreased plasma methionine level. Brain magnetic resonance imaging (MRI) revealed leukoencephalopathy. DNA gene sequencing showed c.446_447 del GC ins TT and c.137G > A, and c.665C > T heterozygous mutations in the MTHFR gene of the patient. Oral administration of betaine drastically improved his clinical symptoms within a few months. After 8 months of treatment, his total plasma homocysteine level moderately decreased; and the plasma methionine concentration became normalized. Furthermore, the white matter lesions on MRI had disappeared. This patient demonstrates the possibility that MTHFR deficiency should be considered in mentally retarded adolescents who display an abnormally elevated plasma level of homocysteine in association with progressive neurological dysfunction and leukoencephalopathy. Febrile infections may be an aggravating factor in patients with MTHFR deficiency.

  1. Severe 5,10-methylenetetrahydrofolate reductase deficiency and two MTHFR variants in an adolescent with progressive myoclonic epilepsy.

    PubMed

    D'Aco, Kristin E; Bearden, David; Watkins, David; Hyland, Keith; Rosenblatt, David S; Ficicioglu, Can

    2014-08-01

    5,10-Methylenetetrahydrofolate reductase (MTHFR) deficiency is an inborn error of the folate-recycling pathway that affects the remethylation of homocysteine to methionine. The clinical presentation of MTHFR deficiency is highly variable ranging from early neurological deterioration and death in infancy to a mild thrombophilia in adults. We describe an adolescent girl with a history of mild learning disabilities who presented at age 14 years with an epilepsy syndrome initially thought to be juvenile myoclonic epilepsy. She later developed intractable epilepsy with myoclonus, leg weakness, cognitive decline, and ataxia consistent with the syndrome of progressive myoclonic epilepsy. This prompted further evaluation that revealed elevated plasma homocysteine and decreased plasma methionine. The diagnosis of MTHFR deficiency was confirmed based on extremely reduced fibroblast MTHFR activity (0.3 nmol CHO/mg prot/hr) as well as mutation analysis that revealed two variants in the MTHFR gene, a splice site mutation p (IVS5-1G>A), as well as a missense mutation (c.155 G>A; p. Arg52Gln). Therapy with folinic acid, betaine, and methionine has produced significant clinical improvement, including improved strength, less severe ataxia, and decreased seizure frequency, as well as improvements in her electroencephalography and electromyography. This patient demonstrates the importance of considering MTHFR deficiency in the differential diagnosis of progressive myoclonic epilepsy because it is one of the few causes for which specific treatment is available. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. The maize brown midrib2 (bm2) gene encodes a methylenetetrahydrofolate reductase that contributes to lignin accumulation

    PubMed Central

    Tang, Ho Man; Liu, Sanzhen; Hill-Skinner, Sarah; Wu, Wei; Reed, Danielle; Yeh, Cheng-Ting; Nettleton, Dan; Schnable, Patrick S

    2014-01-01

    The midribs of maize brown midrib (bm) mutants exhibit a reddish-brown color associated with reductions in lignin concentration and alterations in lignin composition. Here, we report the mapping, cloning, and functional and biochemical analyses of the bm2 gene. The bm2 gene was mapped to a small region of chromosome 1 that contains a putative methylenetetrahydrofolate reductase (MTHFR) gene, which is down-regulated in bm2 mutant plants. Analyses of multiple Mu-induced bm2-Mu mutant alleles confirmed that this constitutively expressed gene is bm2. Yeast complementation experiments and a previously published biochemical characterization show that the bm2 gene encodes a functional MTHFR. Quantitative RT-PCR analyses demonstrated that the bm2 mutants accumulate substantially reduced levels of bm2 transcript. Alteration of MTHFR function is expected to influence accumulation of the methyl donor S-adenosyl-l-methionine (SAM). Because SAM is consumed by two methyltransferases in the lignin pathway (Ye et al., 1994), the finding that bm2 encodes a functional MTHFR is consistent with its lignin phenotype. Consistent with this functional assignment of bm2, the expression patterns of genes in a variety of SAM-dependent or -related pathways, including lignin biosynthesis, are altered in the bm2 mutant. Biochemical assays confirmed that bm2 mutants accumulate reduced levels of lignin with altered composition compared to wild-type. Hence, this study demonstrates a role for MTHFR in lignin biosynthesis. PMID:24286468

  3. The prevalence of methylenetetrahydrofolate reductase 677 C-T, factor V 1691 G-A, and prothrombin 20210 G-A mutations in healthy populations in Setif, Algeria.

    PubMed

    Bourouba, Romyla; Houcher, Bakhouche; Djabi, Farida; Egin, Yonca; Akar, Nejat

    2009-10-01

    The polymorphic mutation 677 C-T in the methylenetetrahydrofolate reductase (MTHFR) gene presents a heterogeneous worldwide distribution and is associated with different disorders such as cardiovascular disease. Its frequency shows great ethnic and geographic variations. The aim of this work is to determine the frequency of MTHFR 677 C-T and coexistence of MTHFR 677 C-T with 2 other common, hereditary thrombophilia causes-namely, factor V 1691 G-A and prothrombin (PT) 20210 G-A mutation-in the Sétif region of Algeria. The study involved 147 apparently healthy participants (82 men and 65 women). Genotyping was carried out by a real-time polymerase chain reaction. The MTHFR 677T carrier frequency was found to be 54.4% (80/147); 59 individuals were heterozygous (40.1%), and 21 were homozygous (14.3%). The frequency of MTHFR 677T was found to be 34.3%. Among the 147 individuals, 3 (2.0%) had factor V Leiden, and 5 (3.4%) had PT 20210 A mutation. Of the 80 participants with MTHFR 677T mutation, 2 had heterozygote factor V 1691 G-A gene mutation, and 4 had heterozygote PT 20210 G-A gene mutation. The results showed that MTHFR 677T prevalence is quite high: an allelic frequency of 34.3% with a genotype frequency of 14.3%. Factor V 1691 G-A and PT 20210 G-A gene mutations are rare in the healthy population of the Sétif region of Algeria.

  4. Individual and Joint Associations of Methylenetetrahydrofolate Reductase C677T Genotype and Plasma Homocysteine With Dyslipidemia in a Chinese Population With Hypertension.

    PubMed

    Liu, Yanhong; Li, Kang; Venners, Scott A; Hsu, Yi-Hsiang; Jiang, Shanqun; Weinstock, Justin; Wang, Binyan; Tang, Genfu; Xu, Xiping

    2017-04-01

    We aimed to examine the cross-sectional associations of plasma total homocysteine (tHcy) concentrations and methylenetetrahydrofolate reductase ( MTHFR) C677T genotype with dyslipidemia. A total of 231 patients with mild-to-moderate essential hypertension were enrolled from the Huoqiu and Yuexi communities in Anhui Province, China. Plasma tHcy levels were measured by high-performance liquid chromatography. Genotyping was performed by TaqMan allelic discrimination technique. Compared with MTHFR 677 CC + CT genotype carriers, TT genotype carriers had higher odds of hypercholesterolemia (adjusted odds ratio [OR] [95% confidence interval (CI)]: 2.7 [1.4-5.2]; P = .004) and higher odds of abnormal low-density lipoprotein cholesterol (adjusted OR [95% CI]: 2.3 [1.1-4.8]; P = .030). The individuals with the TT genotype had higher concentrations of log(tHcy) than those with the 677 CC + CT genotype (adjusted β [standard error]: .2 [0.03]; P < .001). Patients with tHcy ≥ 10 μmol/L had significantly higher odds of hypercholesterolemia (adjusted OR [95% CI]: 2.4 [1.2-4.7]; P = .010). Furthermore, patients with both the TT genotype and the tHcy ≥ 10 μmol/L had the highest odds of hypercholesterolemia (adjusted OR [95% CI]: 4.1 [1.8-9.4]; P = .001) and low-density lipoprotein cholesterol (adjusted OR [95% CI]: 2.4 [1.0-6.0]; P = .064). This study suggests that both tHcy and the MTHFR C677T gene polymorphism may be important determinants of the incidence of dyslipidemia in Chinese patients with essential hypertension. Further studies are needed to confirm the role of tHcy and the MTHFR C677T mutation in the development of dyslipidemia in a larger sample.

  5. Altered protein phosphatase 2A methylation and Tau phosphorylation in the young and aged brain of methylenetetrahydrofolate reductase (MTHFR) deficient mice

    PubMed Central

    Sontag, Jean-Marie; Wasek, Brandi; Taleski, Goce; Smith, Josephine; Arning, Erland; Sontag, Estelle; Bottiglieri, Teodoro

    2014-01-01

    Common functional polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, a key enzyme in folate and homocysteine metabolism, influence risk for a variety of complex disorders, including developmental, vascular, and neurological diseases. MTHFR deficiency is associated with elevation of homocysteine levels and alterations in the methylation cycle. Here, using young and aged Mthfr knockout mouse models, we show that mild MTHFR deficiency can lead to brain-region specific impairment of the methylation of Ser/Thr protein phosphatase 2A (PP2A). Relative to wild-type controls, decreased expression levels of PP2A and leucine carboxyl methyltransferase (LCMT1) were primarily observed in the hippocampus and cerebellum, and to a lesser extent in the cortex of young null Mthfr−/− and aged heterozygous Mthfr+/− mice. A marked down regulation of LCMT1 correlated with the loss of PP2A/Bα holoenzymes. Dietary folate deficiency significantly decreased LCMT1, methylated PP2A and PP2A/Bα levels in all brain regions examined from aged Mthfr+/+ mice, and further exacerbated the regional effects of MTHFR deficiency in aged Mthfr+/− mice. In turn, the down regulation of PP2A/Bα was associated with enhanced phosphorylation of Tau, a neuropathological hallmark of Alzheimer’s disease (AD). Our findings identify hypomethylation of PP2A enzymes, which are major CNS phosphatases, as a novel mechanism by which MTHFR deficiency and Mthfr gene-diet interactions could lead to disruption of neuronal homeostasis, and increase the risk for a variety of neuropsychiatric disorders, including age-related diseases like sporadic AD. PMID:25202269

  6. A common mutation in the 5,10-methylenetetrahydrofolate reductase gene affects genomic DNA methylation through an interaction with folate status

    PubMed Central

    Friso, Simonetta; Choi, Sang-Woon; Girelli, Domenico; Mason, Joel B.; Dolnikowski, Gregory G.; Bagley, Pamela J.; Olivieri, Oliviero; Jacques, Paul F.; Rosenberg, Irwin H.; Corrocher, Roberto; Selhub, Jacob

    2002-01-01

    DNA methylation, an essential epigenetic feature of DNA that modulates gene expression and genomic integrity, is catalyzed by methyltransferases that use the universal methyl donor S-adenosyl-l-methionine. Methylenetetrahydrofolate reductase (MTHFR) catalyzes the synthesis of 5-methyltetrahydrofolate (5-methylTHF), the methyl donor for synthesis of methionine from homocysteine and precursor of S-adenosyl-l-methionine. In the present study we sought to determine the effect of folate status on genomic DNA methylation with an emphasis on the interaction with the common C677T mutation in the MTHFR gene. A liquid chromatography/MS method for the analysis of nucleotide bases was used to assess genomic DNA methylation in peripheral blood mononuclear cell DNA from 105 subjects homozygous for this mutation (T/T) and 187 homozygous for the wild-type (C/C) MTHFR genotype. The results show that genomic DNA methylation directly correlates with folate status and inversely with plasma homocysteine (tHcy) levels (P < 0.01). T/T genotypes had a diminished level of DNA methylation compared with those with the C/C wild-type (32.23 vs.62.24 ng 5-methylcytosine/μg DNA, P < 0.0001). When analyzed according to folate status, however, only the T/T subjects with low levels of folate accounted for the diminished DNA methylation (P < 0.0001). Moreover, in T/T subjects DNA methylation status correlated with the methylated proportion of red blood cell folate and was inversely related to the formylated proportion of red blood cell folates (P < 0.03) that is known to be solely represented in those individuals. These results indicate that the MTHFR C677T polymorphism influences DNA methylation status through an interaction with folate status. PMID:11929966

  7. Methylenetetrahydrofolate reductase activity is involved in the plasma membrane redox system required for pigment biosynthesis in filamentous fungi.

    PubMed

    Frandsen, Rasmus J N; Albertsen, Klaus Selk; Stougaard, Peter; Sørensen, Jens L; Nielsen, Kristian F; Olsson, Stefan; Giese, Henriette

    2010-08-01

    Methylenetetrahydrofolate reductases (MTHFRs) play a key role in biosynthesis of methionine and S-adenosyl-l-methionine (SAM) via the recharging methionine biosynthetic pathway. Analysis of 32 complete fungal genomes showed that fungi were unique among eukaryotes by having two MTHFRs, MET12 and MET13. The MET12 type contained an additional conserved sequence motif compared to the sequences of MET13 and MTHFRs from other eukaryotes and bacteria. Targeted gene replacement of either of the two MTHFR encoding genes in Fusarium graminearum showed that they were essential for survival but could be rescued by exogenous methionine. The F. graminearum strain with a mutation of MET12 (FgDeltaMET12) displayed a delay in the production of the mycelium pigment aurofusarin and instead accumulated nor-rubrofusarin and rubrofusarin. High methionine concentrations or prolonged incubation eventually led to production of aurofusarin in the MET12 mutant. This suggested that the chemotype was caused by a lack of SAM units for the methylation of nor-rubrofusarin to yield rubrofusarin, thereby imposing a rate-limiting step in aurofusarin biosynthesis. The FgDeltaMET13 mutant, however, remained aurofusarin deficient at all tested methionine concentrations and instead accumulated nor-rubrofusarin and rubrofusarin. Analysis of MET13 mutants in F. graminearum and Aspergillus nidulans showed that both lacked extracellular reduction potential and were unable to complete mycelium pigment biosynthesis. These results are the first to show that MET13, in addition to its function in methionine biosynthesis, is required for the generation of the extracellular reduction potential necessary for pigment production in filamentous fungi.

  8. C677T mutation in methylenetetrahydrofolate reductase gene and neural tube defects: should Japanese women undergo gene screening before pregnancy?

    PubMed

    Kondo, Atsuo; Fukuda, Hiromi; Matsuo, Takuya; Shinozaki, Keiko; Okai, Ikuyo

    2014-02-01

    We analyzed the role of maternal C677T mutation in methylenetetrahydrofolate reductase (MTHFR) gene on spina bifida development in newborns. A total of 115 mothers who had given birth to a spina bifida child (SB mothers) gave 10 mL of blood together with written informed consent. The genotype distribution of C677T mutation was assessed and compared with that of the 4517 control individuals. The prevalence of the homozygous genotype (TT) among SB mothers was not significantly different from that among the controls (odds ratio [OR] = 0.65; 95% confidence interval [CI] = 0.31-1.25; P = 0.182), suggesting that MTHFR 677TT genotype in Japan is not associated with spina bifida development in newborns. The T allele frequency was not increased in SB mothers (34.8%) as compared to that of the control individuals (38.2%). Further, the internationally reported association between the two groups was found to be similar in all 15 countries studied except the Netherlands, where the TT genotype was found to be a genetic risk factor for spina bifida. For the prevention of affected pregnancy every woman planning to conceive has to take folic acid supplements 400 μg a day and the government is asked to take action in implementing food fortification with folic acid in the near future. In conclusion, it is not necessary for Japanese women to undergo genetic screening C677T mutation of the MTHFR gene as a predictive marker for spina bifida prior to pregnancy, because the TT genotype is not a risk factor for having an affected infant.

  9. A second common mutation in the methylenetetrahydrofolate reductase gene: an additional risk factor for neural-tube defects?

    PubMed Central

    van der Put, N M; Gabreëls, F; Stevens, E M; Smeitink, J A; Trijbels, F J; Eskes, T K; van den Heuvel, L P; Blom, H J

    1998-01-01

    Recently, we showed that homozygosity for the common 677(C-->T) mutation in the methylenetetrahydrofolate reductase (MTHFR) gene, causing thermolability of the enzyme, is a risk factor for neural-tube defects (NTDs). We now report on another mutation in the same gene, the 1298(A-->C) mutation, which changes a glutamate into an alanine residue. This mutation destroys an MboII recognition site and has an allele frequency of .33. This 1298(A-->C) mutation results in decreased MTHFR activity (one-way analysis of variance [ANOVA] P < .0001), which is more pronounced in the homozygous than heterozygous state. Neither the homozygous nor the heterozygous state is associated with higher plasma homocysteine (Hcy) or a lower plasma folate concentration-phenomena that are evident with homozygosity for the 677(C-->T) mutation. However, there appears to be an interaction between these two common mutations. When compared with heterozygosity for either the 677(C-->T) or 1298(A-->C) mutations, the combined heterozygosity for the 1298(A-->C) and 677(C-->T) mutations was associated with reduced MTHFR specific activity (ANOVA P < .0001), higher Hcy, and decreased plasma folate levels (ANOVA P <.03). Thus, combined heterozygosity for both MTHFR mutations results in similar features as observed in homozygotes for the 677(C-->T) mutation. This combined heterozygosity was observed in 28% (n =86) of the NTD patients compared with 20% (n =403) among controls, resulting in an odds ratio of 2.04 (95% confidence interval: .9-4.7). These data suggest that the combined heterozygosity for the two MTHFR common mutations accounts for a proportion of folate-related NTDs, which is not explained by homozygosity for the 677(C-->T) mutation, and can be an additional genetic risk factor for NTDs. PMID:9545395

  10. Methylenetetrahydrofolate Reductase Activity Is Involved in the Plasma Membrane Redox System Required for Pigment Biosynthesis in Filamentous Fungi ▿ †

    PubMed Central

    Frandsen, Rasmus J. N.; Albertsen, Klaus Selk; Stougaard, Peter; Sørensen, Jens L.; Nielsen, Kristian F.; Olsson, Stefan; Giese, Henriette

    2010-01-01

    Methylenetetrahydrofolate reductases (MTHFRs) play a key role in biosynthesis of methionine and S-adenosyl-l-methionine (SAM) via the recharging methionine biosynthetic pathway. Analysis of 32 complete fungal genomes showed that fungi were unique among eukaryotes by having two MTHFRs, MET12 and MET13. The MET12 type contained an additional conserved sequence motif compared to the sequences of MET13 and MTHFRs from other eukaryotes and bacteria. Targeted gene replacement of either of the two MTHFR encoding genes in Fusarium graminearum showed that they were essential for survival but could be rescued by exogenous methionine. The F. graminearum strain with a mutation of MET12 (FgΔMET12) displayed a delay in the production of the mycelium pigment aurofusarin and instead accumulated nor-rubrofusarin and rubrofusarin. High methionine concentrations or prolonged incubation eventually led to production of aurofusarin in the MET12 mutant. This suggested that the chemotype was caused by a lack of SAM units for the methylation of nor-rubrofusarin to yield rubrofusarin, thereby imposing a rate-limiting step in aurofusarin biosynthesis. The FgΔMET13 mutant, however, remained aurofusarin deficient at all tested methionine concentrations and instead accumulated nor-rubrofusarin and rubrofusarin. Analysis of MET13 mutants in F. graminearum and Aspergillus nidulans showed that both lacked extracellular reduction potential and were unable to complete mycelium pigment biosynthesis. These results are the first to show that MET13, in addition to its function in methionine biosynthesis, is required for the generation of the extracellular reduction potential necessary for pigment production in filamentous fungi. PMID:20543064

  11. Clinical pattern, mutations and in vitro residual activity in 33 patients with severe 5, 10 methylenetetrahydrofolate reductase (MTHFR) deficiency.

    PubMed

    Huemer, Martina; Mulder-Bleile, Regina; Burda, Patricie; Froese, D Sean; Suormala, Terttu; Zeev, Bruria Ben; Chinnery, Patrick F; Dionisi-Vici, Carlo; Dobbelaere, Dries; Gökcay, Gülden; Demirkol, Mübeccel; Häberle, Johannes; Lossos, Alexander; Mengel, Eugen; Morris, Andrew A; Niezen-Koning, Klary E; Plecko, Barbara; Parini, Rossella; Rokicki, Dariusz; Schiff, Manuel; Schimmel, Mareike; Sewell, Adrian C; Sperl, Wolfgang; Spiekerkoetter, Ute; Steinmann, Beat; Taddeucci, Grazia; Trejo-Gabriel-Galán, Jose M; Trefz, Friedrich; Tsuji, Megumi; Vilaseca, María Antònia; von Kleist-Retzow, Jürgen-Christoph; Walker, Valerie; Zeman, Jiri; Baumgartner, Matthias R; Fowler, Brian

    2016-01-01

    Severe methylenetetrahydrofolate reductase (MTHFR) deficiency is a rare inborn defect disturbing the remethylation of homocysteine to methionine (<200 reported cases). This retrospective study evaluates clinical, biochemical genetic and in vitro enzymatic data in a cohort of 33 patients. Clinical, biochemical and treatment data was obtained from physicians by using a questionnaire. MTHFR activity was measured in primary fibroblasts; genomic DNA was extracted from cultured fibroblasts. Thirty-three patients (mean age at follow-up 11.4 years; four deceased; median age at first presentation 5 weeks; 17 females) were included. Patients with very low (<1.5%) mean control values of enzyme activity (n = 14) presented earlier and with a pattern of feeding problems, encephalopathy, muscular hypotonia, neurocognitive impairment, apnoea, hydrocephalus, microcephaly and epilepsy. Patients with higher (>1.7-34.8%) residual enzyme activity had mainly psychiatric symptoms, mental retardation, myelopathy, ataxia and spasticity. Treatment with various combinations of betaine, methionine, folate and cobalamin improved the biochemical and clinical phenotype. During the disease course, patients with very low enzyme activity showed a progression of feeding problems, neurological symptoms, mental retardation, and psychiatric disease while in patients with higher residual enzyme activity, myelopathy, ataxia and spasticity increased. All other symptoms remained stable or improved in both groups upon treatment as did brain imaging in some cases. No clear genotype-phenotype correlation was obvious. MTHFR deficiency is a severe disease primarily affecting the central nervous system. Age at presentation and clinical pattern are correlated with residual enzyme activity. Treatment alleviates biochemical abnormalities and clinical symptoms partially.

  12. Plasma homocysteine in adolescents depends on the interaction between methylenetetrahydrofolate reductase genotype, lipids and folate: a seroepidemiological study

    PubMed Central

    Gil-Prieto, Ruth; Hernández, Valentín; Cano, Beatriz; Oya, Manuel; Gil, Ángel

    2009-01-01

    Background Many publications link high homocysteine levels to cardiovascular disease. In Spain there is little information on the prevalence of hyperhomocysteinaemia and associated vitamin factors among the general population, and less still among children. Cardiovascular risk factors in the childhood population may be related to the appearance of cardiovascular disease at adult age. The aim of this study is to establish a definition of hyperhomocysteinaemia in adolescents and to analyze the influence of vitamin and metabolic factors in homocysteine levels in this population group. Methods Descriptive, cross-sectional epidemiological study to estimate serum homocysteine, vitamin B12 and folate levels, as well as plasma total, HDL- and LDL- cholesterol in a schoolgoing population aged 13 to 17 years in Madrid, Spain. Spearman correlation analysis was performed to ascertain quantitative comparison, Pearson's χ2 test (frequency < 5, Fisher) was used for comparison of prevalences, Mann-Whitney U and Kruskal-Wallis test were used for comparison of means and Bonferroni correction was used for post-hoc tests. A multivariate logistic regression model was performed in the multivariate analysis. Results Based on the classic values for definition of hyperhomocysteinaemia in adults, prevalence of hyperhomocysteinaemia in the study population was: 1.26% for 15 μmol/L; and 2.52% for 12 μmol/L. Deficits in HDL cholesterol and serum folate levels yielded adjusted Odds Ratios (OR) for hyperhomocysteinemia of 2.786, 95% CI (1.089-7.126), and 5.140, 95% CI (2.347-11.256) respectively. Mutation of the methylenetetrahydrofolate reductase (MTHFR) C677T genotype also raises the risk of hyperhomocysteinaemia (CC→CT: OR = 2.362; 95% CI (1.107-5.042) CC→TT: OR = 6.124, 95% CI (2.301-16.303)) Conclusion A good definition of hyperhomocysteinaemia in adolescents is the 90th percentile, equivalent to 8.23 μmol/L. Risk factors for hyperhomocysteinaemia are cHDL and folate deficiency, and

  13. The Prevalence of Factor V Leiden (G1691A) and Methylenetetrahydrofolate Reductase C677T Mutations in Sickle Cell Disease in Western India.

    PubMed

    Kangne, Harshada K; Jijina, Farah F; Italia, Yazdi M; Jain, Dipti L; Nadkarni, Anita H; Ghosh, Kanjaksha K; Colah, Roshan B

    2015-03-01

    The prevalence of the Factor V Leiden (FVL; G1691A) mutation and the methylenetetrahydrofolate reductase (MTHFR; C677T) mutation was determined in 180 patients with sickle cell (SS) disease (126 sickle homozygous and 54 sickle β-thalassaemia--age 1-47 years) and in 130 healthy controls. The FVL mutation in the heterozygous state was present in only 3 patients with SS disease and was absent in the controls. Genotyping of MTHFR 677C > T revealed increased frequency of the C allele than the T allele in patients as well as in controls. This suggests that these genetic markers may not be major risk factors for a hypercoagulable state in Indian patients with SS disease.

  14. Thyroid vein thrombosis in a young woman with methylenetetrahydrofolate reductase gene mutation receiving cyproterone acetate/ethinylestradiol treatment for polycystic ovary syndrome: a case report.

    PubMed

    Nazli, Yunus; Colak, Necmettin; Aksoy, Omer N; Cakir, Omer

    2011-06-01

    Thyroid vein thrombosis is a rare variety of venous thrombosis. The use of oral contraceptives and heterozygous methylenetetrahydrofolate reductase (MTHFR) gene mutation could have synergistic effects on the onset of venous thromboembolism. We report a 28-year-old woman with thyroid vein thrombosis. The thrombosis was possibly provoked by a combination of heterozygous MTHFR gene mutation and the use of a combined oral contraceptive (COC) containing cyproterone acetate/ethinylestradiol (CPA/EE) for polycystic ovary syndrome (PCOS). The patient was treated successfully with low molecular weight heparin and oral anticoagulation. The thyroid vein thrombosis resolved and the patient was advised to maintain lifelong use of anticoagulation therapy. Our report emphasizes that the combination of heterozygous MTHFR gene mutation, PCOS, and the use of a COC-containing CPA/EE could increase risk of thyroid vein thrombosis in young adults.

  15. Identification of a putative methylenetetrahydrofolate reductase by sequence analysis of a 6.8 kb DNA fragment of yeast chromosome VII.

    PubMed

    Tizon, B; Rodríguez-Torres, M; Rodríguez-Belmonte, E; Cadahia, J L; Cerdan, E

    1996-09-01

    We report the sequence analysis of a 6.8 kb DNA fragment from Saccharomyces cerevisiae chromosome VII. This sequence contains five open reading frames (ORFs) greater than 100 amino acids. There is also an incomplete ORF flanking one of the extremes, G2868, which is the 3' end of the SCS3 gene (Hosaka et al., 1994). The translated sequence of ORF G2882 shows similarity to the human methylenetetrahydrofolate reductase (Goyette et al., 1994). ORF G2889 shows no significant homologies with the sequences compiled in databases. ORF G2893 corresponds to the gene SUP44, coding for the yeast ribosomal protein S4 (All-Robin et al., 1990). G2873 and G2896 are internal ORFs.

  16. Increased resistance to malaria in mice with methylenetetrahydrofolate reductase (Mthfr) deficiency suggests a mechanism for selection of the MTHFR 677C>T (c.665C>T) variant.

    PubMed

    Meadows, Danielle N; Pyzik, Michal; Wu, Qing; Torre, Sabrina; Gros, Philippe; Vidal, Silvia M; Rozen, Rima

    2014-05-01

    The polymorphism 677C>T (NM_005957.4:c.665C>T/p.Ala222Val, rs1801133:C>T) in methylenetetrahydrofolate reductase (MTHFR) results in mild enzymatic deficiency and increased risk for several complex traits including adverse reproductive outcomes, birth defects, and heart disease. Despite these deleterious effects, homozygosity is high (5%-15%) in many populations, and among the highest in Mediterranean regions, where malaria was historically endemic and may have conferred a selective advantage for other mutations. We infected Mthfr-deficient (Mthfr(+) (/-) ) and MTHFR overexpressing (MTHFR(Tg) ) mice with Plasmodium berghei ANKA to induce cerebral malaria. Mthfr(+/-) mice survived longer (P < 0.02, log-rank test), and MTHFR(Tg) mice died earlier (P < 0.05, log-rank test) after infection compared with wild-type littermates. Flow cytometry revealed increased lymphocyte populations and increased CCR4(+) NK cells in spleen of Mthfr(+) (/-) mice; MTHFR(Tg) animals had decreased numbers of these NK cells. Interferon-γ and interleukin-10 immunoreactive proteins were increased and decreased, respectively, in brain of Mthfr(+/-) mice compared with wild-type. We suggest that mild MTHFR deficiency protects against malarial infection and that this phenomenon may have led to the high frequency of the 677C>T/c.665C>T variant in human populations. © 2014 WILEY PERIODICALS, INC.

  17. The methylenetetrahydrofolate reductase C677T mutation induces cell-specific changes in genomic DNA methylation and uracil misincorporation: a possible molecular basis for the site-specific cancer risk modification.

    PubMed

    Sohn, Kyoung-Jin; Jang, Hyeran; Campan, Mihaela; Weisenberger, Daniel J; Dickhout, Jeffrey; Wang, Yi-Cheng; Cho, Robert C; Yates, Zoe; Lucock, Mark; Chiang, En-Pei; Austin, Richard C; Choi, Sang-Woon; Laird, Peter W; Kim, Young-In

    2009-05-01

    The C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene is associated with a decreased risk of colon cancer although it may increase the risk of breast cancer. This polymorphism is associated with changes in intracellular folate cofactors, which may affect DNA methylation and synthesis via altered one-carbon transfer reactions. We investigated the effect of this mutation on DNA methylation and uracil misincorporation and its interaction with exogenous folate in further modulating these biomarkers of one-carbon transfer reactions in an in vitro model of the MTHFR 677T mutation in HCT116 colon and MDA-MB-435 breast adenocarcinoma cells. In HCT116 cells, the MTHFR 677T mutation was associated with significantly increased genomic DNA methylation when folate supply was adequate or high; however, in the setting of folate insufficiency, this mutation was associated with significantly decreased genomic DNA methylation. In contrast, in MDA-MB-435 cells, the MTHFR 677T mutation was associated with significantly decreased genomic DNA methylation when folate supply was adequate or high and with no effect when folate supply was low. The MTHFR 677T mutation was associated with a nonsignificant trend toward decreased and increased uracil misincorporation in HCT116 and MDA-MB-435 cells, respectively. Our data demonstrate for the first time a functional consequence of changes in intracellular folate cofactors resulting from the MTHFR 677T mutation in cells derived from the target organs of interest, thus providing a plausible cellular mechanism that may partly explain the site-specific modification of colon and breast cancer risks associated with the MTHFR C677T mutation.

  18. Association of Methylentetraydrofolate Reductase (MTHFR) 677 C > T gene polymorphism and homocysteine levels in psoriasis vulgaris patients from Malaysia: a case-control study

    PubMed Central

    2012-01-01

    Background The methylenetetrahydrofolate reductase (MTHFR) enzyme catalyzes the reduction of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate and methyl donors. The methyl donors are required for the conversion of homocysteine to methionine. Mutation of MTHFR 677 C > T disrupts its thermostability therefore leads to defective enzyme activities and dysregulation of homocysteine levels. Methods This case-control study (n = 367) was conducted to investigate the correlation of the MTHFR gene polymorphism [NM_005957] and psoriasis vulgaris amongst the Malaysian population. Overnight fasting blood samples were collected from a subgroup of consented psoriasis vulgaris patients and matched controls (n = 84) for the quantification of homocysteine, vitamin B12 and folic acid levels. Results There was no significant increase of the MTHFR 677 C > T mutation in patients with psoriasis vulgaris compared with controls (χ2 = 0.733, p = 0.392). No significant association between homocysteine levels and MTHFR gene polymorphism in cases and controls were observed (F = 0.91, df = 3, 80, p = 0.44). However, homocysteine levels in cases were negatively correlated with vitamin B12 (r = -0.173) and folic acid (r = -0.345) levels. Vitamin B12 and folic acid levels in cases were also negatively correlated (r = -0.164). Conclusions Our results indicate that there was no significant association between the MTHFR gene polymorphism and psoriasis vulgaris in the Malaysian population. There was no significant increase of the plasma homocysteine level in the psoriasis patients compared to the controls. PMID:22217364

  19. Massive pulmonary embolism associated with Factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase gene mutations in a young patient on oral contraceptive pills: a case report.

    PubMed

    Charafeddine, Khalil M; Mahfouz, Rami A; Ibrahim, Georges Y; Taher, Ali T; Hoballah, Jamal J; Taha, Assad M

    2010-10-01

    Factor V Leiden (Factor V G1691A), prothrombin gene mutation G20210A, and homozygous C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene are known to predispose venous thromboembolism (VTE). We present herein a rare case of a young woman heterozygous for these mutations and taking oral contraceptive pills for less than 2 months, diagnosed to have massive deep venous thrombosis and bilateral pulmonary embolism. The patient was managed for 10 days in the hospital and discharged home on oral anticoagulants. This case suggests that screening for these factors in people with family history of thrombosis and in relatives of patients with these mutations is highly recommended to prevent fatal consequences. In addition, a new guideline for treatment and prophylaxis with anticoagulant for these patients and others who are at risk of developing VTE (American College of Chest Physicians [ACCP] guidelines-Chest 2008) has been published recently. Our recommendation is to promote for the internationally published algorithms through their application, where necessary, to prevent any future thrombotic morbidity or mortality incidents.

  20. Recurrent cerebral venous thrombosis associated with heterozygote methylenetetrahydrofolate reductase C677T mutation and sickle cell trait without homocysteinemia: an autopsy case report and review of literature.

    PubMed

    Ali, Z; Troncoso, J C; Fowler, D R

    2014-09-01

    Elevated blood homocysteine concentration and certain genetic mutations have been associated with increased risk for developing arterial and venous thrombosis. A common mutation of methylenetetrahydrofolate reductase, MTHFR C677T, has been associated with elevated homocysteine concentration and increased risk for developing thrombosis in homozygote carriers. Heterozygote carriers for this gene mutation, if associated with other major or minor risk factors for thrombophilia, appear to be prone to develop thrombosis. A postmortem genetic testing for common mutations resulting in thrombophilia should be performed in all individuals who die as a result of thrombosis, regardless of predisposing risk factors, to determine the true prevalence of mutations in these individuals, and to assess the true role of a certain mutation, such as heterozygote MTHFR C677T, in the pathogenesis of thrombosis. Postmortem genetic testing for common mutations associated with thrombophilia in selected cases has potentially life-saving importance to surviving family members. We report a case of recurrent cerebral venous thrombosis in a 19 year old male with history of sickle cell trait, obesity, and high normal blood homocysteine, who was heterozygote for MTHFR C677T mutation.

  1. Factor V Leiden, factor V Cambridge, factor II GA20210, and methylenetetrahydrofolate reductase in cerebral venous and sinus thrombosis: A case-control study

    PubMed Central

    Saadatnia, Mohammad; Salehi, Mansour; Movahedian, Ahmad; Shariat, Seyed Ziaeddin Samsam; Salari, Mehri; Tajmirriahi, Marzieh; Asadimobarakeh, Elham; Salehi, Rasoul; Amini, Gilda; Ebrahimi, Homa; Kheradmand, Ehsan

    2015-01-01

    Background: Factor V G1691A (FV Leiden), FII GA20210, and methylenetetrahydrofolate reductase (MTHFR) C677T mutations are the most common genetic risk factors for thromboembolism in the Western countries. However, there is rare data in Iran about cerebral venous and sinus thrombosis (CVST) patients. The aim of this study was to evaluate the frequency of common genetic thrombophilic factors in CVST patients. Materials and Methods: Forty consequently CVST patients from two University Hospital in Isfahan University of Medical Sciences aged more than 15 years from January 2009 to January 2011 were recruited. In parallel, 51 healthy subjects with the same age and race from similar population selected as controls. FV Leiden, FII GA20210, MTHFR C677T, and FV Cambridge gene mutations by polymerase chain reaction technique were evaluated in case and control groups. Results: FV Leiden, FII GA20210, and FV Cambridge gene mutations had very low prevalence in both case (5%, 2%, 0%) and control (2.5%, 0%, 0%) and were not found any significant difference between groups. MTHFR C677T mutations was in 22 (55%) of patients in case group and 18 (35.5%) of control group (P = 0.09). Conclusion: This study showed that the prevalence of FV Leiden, FII GA20210, and FV Cambridge were low. Laboratory investigations of these mutations as a routine test for all patients with CVST may not be cost benefit. PMID:26600830

  2. Factor V Leiden, factor V Cambridge, factor II GA20210, and methylenetetrahydrofolate reductase in cerebral venous and sinus thrombosis: A case-control study.

    PubMed

    Saadatnia, Mohammad; Salehi, Mansour; Movahedian, Ahmad; Shariat, Seyed Ziaeddin Samsam; Salari, Mehri; Tajmirriahi, Marzieh; Asadimobarakeh, Elham; Salehi, Rasoul; Amini, Gilda; Ebrahimi, Homa; Kheradmand, Ehsan

    2015-06-01

    Factor V G1691A (FV Leiden), FII GA20210, and methylenetetrahydrofolate reductase (MTHFR) C677T mutations are the most common genetic risk factors for thromboembolism in the Western countries. However, there is rare data in Iran about cerebral venous and sinus thrombosis (CVST) patients. The aim of this study was to evaluate the frequency of common genetic thrombophilic factors in CVST patients. Forty consequently CVST patients from two University Hospital in Isfahan University of Medical Sciences aged more than 15 years from January 2009 to January 2011 were recruited. In parallel, 51 healthy subjects with the same age and race from similar population selected as controls. FV Leiden, FII GA20210, MTHFR C677T, and FV Cambridge gene mutations by polymerase chain reaction technique were evaluated in case and control groups. FV Leiden, FII GA20210, and FV Cambridge gene mutations had very low prevalence in both case (5%, 2%, 0%) and control (2.5%, 0%, 0%) and were not found any significant difference between groups. MTHFR C677T mutations was in 22 (55%) of patients in case group and 18 (35.5%) of control group (P = 0.09). This study showed that the prevalence of FV Leiden, FII GA20210, and FV Cambridge were low. Laboratory investigations of these mutations as a routine test for all patients with CVST may not be cost benefit.

  3. Alteration of the Alkaloid Profile in Genetically Modified Tobacco Reveals a Role of Methylenetetrahydrofolate Reductase in Nicotine N-Demethylation1[C][W][OA

    PubMed Central

    Hung, Chiu-Yueh; Fan, Longjiang; Kittur, Farooqahmed S.; Sun, Kehan; Qiu, Jie; Tang, She; Holliday, Bronwyn M.; Xiao, Bingguang; Burkey, Kent O.; Bush, Lowell P.; Conkling, Mark A.; Roje, Sanja; Xie, Jiahua

    2013-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme of the tetrahydrofolate (THF)-mediated one-carbon (C1) metabolic network. This enzyme catalyzes the reduction of 5,10-methylene-THF to 5-methyl-THF. The latter donates its methyl group to homocysteine, forming methionine, which is then used for the synthesis of S-adenosyl-methionine, a universal methyl donor for numerous methylation reactions, to produce primary and secondary metabolites. Here, we demonstrate that manipulating tobacco (Nicotiana tabacum) MTHFR gene (NtMTHFR1) expression dramatically alters the alkaloid profile in transgenic tobacco plants by negatively regulating the expression of a secondary metabolic pathway nicotine N-demethylase gene, CYP82E4. Quantitative real-time polymerase chain reaction and alkaloid analyses revealed that reducing NtMTHFR expression by RNA interference dramatically induced CYP82E4 expression, resulting in higher nicotine-to-nornicotine conversion rates. Conversely, overexpressing NtMTHFR1 suppressed CYP82E4 expression, leading to lower nicotine-to-nornicotine conversion rates. However, the reduced expression of NtMTHFR did not affect the methionine and S-adenosyl-methionine levels in the knockdown lines. Our finding reveals a new regulatory role of NtMTHFR1 in nicotine N-demethylation and suggests that the negative regulation of CYP82E4 expression may serve to recruit methyl groups from nicotine into the C1 pool under C1-deficient conditions. PMID:23221678

  4. Frequency of the C677T variant of the methylenetetrahydrofolate reductase (MTHFR) gene in patients with migraine with or without aura - a preliminary report.

    PubMed

    Szczygioł, Dorota; Motta, Ewa; Gołba, Anna; Stęposz, Arkadiusz; Witecka, Joanna; Dębski, Marek; Błaszkiewicz, Daria; Sieroń, Aleksander

    2012-01-01

    The aim of our study was to evaluate the frequency of the C677T variant in the methylenetetrahydrofolate reductase (MTHFR) gene in patients with migraine with or without aura and to find an association between this variant and vascular lesions in magnetic resonance imaging of the head, presence of patent foramen ovale (PFO) and increased level of homocysteine. Ninety-one patients with migraine, aged 19-57, were investigated in this study. The MTHFR C677T variant was genotyped in this group and levels of homocysteine, folic acid and vitamin B12 were measured. Transcranial Doppler sonography with test for PFO detection by injection of air contrast during the Valsalva manoeuvre was performed in each patient. Frequency of the C677T variant in the MTHFR gene was similar in patients and controls. Hyperhomocysteinaemia was significantly more frequent in migraine patients with the C677T variant. The prevalence of PFO was significantly higher in migraine patients with aura and the homozygous variant of the MTHFR gene. Frequency of the C677T variant in the MTHFR gene was similar in patients and controls. Significantly more frequent prevalence of PFO in migraine patients with aura (with homozygous recessive genotype of MTHFR probably suggests their common genetic basis. Hyperhomocysteinaemia was significantly more frequent in migraine patients with the C677T variant, which could be an additional risk factor of this disease.

  5. Elevated total plasma homocysteine and 667C{r_arrow}T mutation of the 5,10-methylenetetrahydrofolate reductase gene in thrombotic vascular disease

    SciTech Connect

    De Franchis, R.; Sebastio, G.; Andria, G.

    1996-07-01

    Moderate elevation of total plasma homocysteine (tHcy) has been reported as an independent risk factor for thrombotic vascular disease, a well-known multifactorial disorder. Possible genetic causes of elevated tHcy include defects of the sulfur-containing amino acids metabolism due to deficiencies of cystathionine {Beta}-synthase, of 5,10-methylenetetrahydrofolate reductase (MTHFR), and of the enzymes of cobalamin metabolism. An impaired activity of MTHFR due to a thermolabile form of the enzyme has been observed in {le}28% of hyperhomocysteinemic patients with premature vascular disease. More recently, the molecular basis of such enzymatic thermolability has been related to a common mutation of the MTHFR gene, causing a C-to-T substitution at nt 677 (677C{r_arrow}T). This mutation was found in 38% of unselected chromosomes from 57 French Canadian individuals. The homozygous state for the mutation was present in 12% of these subjects and correlated with significantly elevated tHcy. Preliminary evidence indicates that the frequency of homozygotes for the 677C{r_arrow}T mutation may vary significantly in populations from different geographic areas. 5 refs., 2 tabs.

  6. Divergent effects of the 677C>T mutation of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene on ovarian responsiveness and anti-Müllerian hormone concentrations.

    PubMed

    Pavlik, Roman; Hecht, Stephanie; Ochsenkühn, Robert; Noss, Ulrich; Lohse, Peter; Thaler, Christian J

    2011-06-01

    To investigate the influence of the 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C>T mutation on serum anti-Müllerian hormone (AMH) concentrations and on the numbers of oocytes retrieved (NOR) following controlled ovarian hyperstimulation (COH). Prospective cohort study. University-based infertility clinic. Two hundred and seventy women undergoing COH for IVF with or without intracytoplasmic sperm injection. None. AMH levels were determined from blood samples collected after 10 days of GnRH superagonist treatment and before COH. The MTHFR 677C>T genotype was characterized by a TaqMan 5' nuclease assay. AMH serum concentrations correlated significantly with the NOR in all individuals studied. Average (±SD) AMH levels of TT carriers (2.85±2.23 ng/mL) were significantly higher than those of homozygous CC (1.91±1.59 ng/mL) or heterozygous CT individuals (2.23±1.74 ng/mL). When evaluated by multiple regression analysis, AMH had a significant positive effect on NOR, whereas age and MTHFR 677TT genotype had significant negative effects. The MTHFR 677TT genotype is associated with higher serum AMH concentrations and has a negative effect on NOR. This apparent paradox might be resolved in light of recent findings describing a negative feedback function of AMH in the coordination of follicle development. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. The model homologue of the partially defective human 5,10-methylenetetrahydrofolate reductase, considered as a risk factor for stroke due to increased homocysteine level, can be protected and reactivated by heat shock proteins.

    PubMed

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

    2016-10-01

    The A222 V substitution in the human MTHFR gene product (5,10-methylenetetrahydrofolate reductase) is responsible for a decreased activity of this enzyme. This may cause an increased homocysteine level, considered as a risk factor for arteriosclerosis and stroke. The bacterial homologue of the human enzyme, MetF, has been found to be a useful model in genetic and biochemical studies. The similarity of Escherichia coli MetF and human MTHFR proteins is so high that particular mutations in the corresponding human gene can be reflected by the bacterial mutants. For example, the A222 V substitution in MTHFR (caused by the C667T substitution in the MTHFR gene) can be ascribed to the A117 V substitution in MetF. Here, it is reported that a temperature-sensitive MetF117 (A117 V) protein can be partially protected from a thermal inactivation by the heat shock proteins from the Hsp70/100 systems. Moreover, activity of the thermally denatured enzyme can be partially restored by the same heat shock proteins. High temperature protein G (HtpG) had no effect on MetF117 activity in both experimental systems. The presented results indicate that functions of heat shock proteins may be required for maintenance of the MetF117 function. This may have implications for the mechanisms of arteriosclerosis and stroke, especially in the light of previous findings that the A222 V MTHFR polymorphism may be a risk factor for stroke, as well as recently published results which demonstrated the increased levels of antibodies against heat shock proteins in stroke patients.

  8. Choline Intake, Plasma Riboflavin, and the Phosphatidylethanolamine N-Methyltransferase G5465A Genotype Predict Plasma Homocysteine in Folate-Deplete Mexican-American Men with the Methylenetetrahydrofolate Reductase 677TT Genotype12

    PubMed Central

    Caudill, Marie A.; Dellschaft, Neele; Solis, Claudia; Hinkis, Sabrina; Ivanov, Alexandre A.; Nash-Barboza, Susan; Randall, Katharine E.; Jackson, Brandi; Solomita, Gina N.; Vermeylen, Francoise

    2009-01-01

    We previously showed that provision of the folate recommended dietary allowance and either 300, 550, 1100, or 2200 mg/d choline for 12 wk resulted in diminished folate status and a tripling of plasma total homocysteine (tHcy) in men with the methylenetetrahydrofolate reductase (MTHFR) 677TT genotype. However, the substantial variation in tHcy within the 677TT genotype at wk 12 implied that several factors were interacting with this genotype to affect homocysteine. As an extension of this work, the present study sought to identify the main predictors of wk-12 plasma tHcy, alone and together with the MTHFR C677T genotype (29 TT, 31 CC), using linear regression analysis. A basic model explaining 82.5% of the variation (i.e. adjusted R2 = 0.825) was constructed. However, the effects of the variables within this model were dependent upon the MTHFR C677T genotype (P for interaction ≤ 0.021). Within the 677TT genotype, serum folate (P = 0.005) and plasma riboflavin (P = 0.002) were strong negative predictors (inversely related) explaining 12 and 15%, respectively, of the variation in tHcy, whereas choline intake (P = 0.003) and serum creatinine (P < 0.001) were strong positive predictors, explaining 19 and 25% of the variation. None of these variables, except creatinine (P = 0.021), correlated with tHcy within the 677CC genotype. Of the 8 additional polymorphisms tested, none appeared to influence tHcy. However, when creatinine was not in the model, the phosphatidylethanolamine N-methyltransferase 5465G→A variant predicted lower tHcy (P < 0.001); an effect confined to the MTHFR 677TT genotype. Thus, in folate-deplete men, several factors with roles in 1-carbon metabolism interact with the MTHFR C677T genotype to affect plasma tHcy. PMID:19211833

  9. A cross-sectional study to find out the relationship of methylenetetrahydrofolate reductase (MTHFR) C677T genotype with plasma levels of folate and total homocysteine by daily folate intake in Japanese.

    PubMed

    Fukuda, Nana; Hamajima, Nobuyuki; Wakai, Kenji; Suzuki, Koji

    2014-01-01

    In those with the methylenetetrahydrofolate reductase (MTHFR) 677TT genotype, enzyme activity is lowered. Therefore, these individuals might require an increased intake of folate to maintain or control blood levels of plasma folate or total homocysteine (tHcy). We examined associations of dietary folate intake with fasting plasma folate and total homocysteine (tHcy) according to genotype among 554 Japanese (207 men and 347 women aged 39-89 y) recruited in 2009. Intake of folate was estimated with a food frequency questionnaire. The MTHFR polymorphism was genotyped by a polymerase chain reaction with confronting two-pair primers. The log-transformed concentration of folate or tHcy was regressed on energy-adjusted folate intake in a linear regression analysis. Higher folate intake was associated with higher plasma folate among those with the CC (β=0.165, p=0.066) or CT (β=0.248, p<0.001) genotypes, and with lower tHcy levels only among those with the CC (β=-0.141, p=0.013) genotype. Plasma folate was significantly and inversely associated with tHcy, irrespective of MTHFR genotype. When the analysis was restricted to those with tHcy levels higher than the reference range (≥13.5 nmol/mL, n=20), these significant associations were not found. The interaction between folate intake or plasma folate and genotype was not significant in any analysis. In conclusion, dietary folate intake was positively associated with plasma folate among those with the CC or CT genotypes and inversely associated with tHcy among those with the CC genotype, but the associations were not clear among those with higher levels of tHcy.

  10. Molecular genetic analysis in mild hyperhomocysteinemia: A common mutation in the methylenetetrahydrofolate reductase gene is a genetic risk factor for cardiovascular disease

    SciTech Connect

    Kluijtmans, L.A.J.; Heuvel, L.P.W.J. van den; Stevens, E.M.B.

    1996-01-01

    Mild hyperhomocysteinemia is an established risk factor for cardiovascular disease. Genetic aberrations in the cystathionine P-synthase (CBS) and methylenetetrahydrofolate reductase (MTHFR) genes may account for reduced enzyme activities and elevated plasma homocysteine levels. In 15 unrelated Dutch patients with homozygous CBS deficiency, we observed the 833T{yields}C (1278T) mutation in 50% of the alleles. Very recently, we identified a common mutation (677C{yields}T; A{yields}V) in the MTHFR gene, which, in homozygous state, is responsible for the thermolabile phenotype and which is associated with decreased specific MTHFR activity and elevated homocysteine levels. We screened 60 cardiovascular patients and 111 controls for these two mutations, to determine whether these mutations are risk factors for premature cardiovascular disease. Heterozygosity for the 833T{yields}C mutation in the CBS gene was observed in one individual of the control group but was absent in patients with premature cardiovascular disease. Homozygosity for the 677C-{yields}T mutation in the MTHFR gene was found in 9 (15%) of 60 cardiovascular patients and in only 6 ({approximately}5%) of 111 control individuals (odds ratio 3.1 [95% confidence interval 1.0-9.21]). Because of both the high prevalence of the 833T-{yields}C mutation among homozygotes for CBS deficiency and its absence in 60 cardiovascular patients, we may conclude that heterozygosity for CBS deficiency does not appear to be involved in premature cardiovascular disease. However, a frequent homozygous mutation in the MTHFR gene is associated with a threefold increase in risk for premature cardiovascular disease. 35 refs., 3 figs., 1 tab.

  11. Association of Transforming Growth Factor Alpha and Methylenetetrahydrofolate reductase gene variants with nonsyndromic cleft lip and palate in the Indian population.

    PubMed

    Desai, Asavari L; Dinesh, M R; Amarnath, B C; Dharma, R M; Akshai, K R; Prashanth, C S

    2014-07-01

    The aim was to evaluate the relationship of the K-primer variant of the transforming growth factor-alpha (TGF-α) gene and C677T variant of the methylenetetrahydrofolate reductase (MTHFR) gene with nonsyndromic cleft lip and palate (CL/P) in the Indian population. The study group consisted of DNA samples of 25 subjects with nonsyndromic CL with or without cleft palate and 25 unrelated controls, already existing in the Department of Orthodontics, D.A.P.M.R.V. Dental College, Bengaluru, Karnataka, India. THE DNA SAMPLES WERE DIVIDED INTO TWO CATEGORIES: Group A which included the 25 subjects with nonsyndromic CL/P; and Group B, which consisted of the 25 unrelated controls. The polymerase chain reaction (PCR) test was done for amplification of the region of interest from the DNA samples. Restriction digestion was then performed on the amplified product using the restriction enzyme HinfI, separately for each of the variants. The digested PCR products were separated into channels on a 1.5% agarose gel containing ethidium bromide in an electrophoretic chamber. A U.V. transilluminator was used to see the specific bands of base pairs of the digested PCR products. In Group A, the TGF-α gene variant was present in 16 subjects (P = 0.001) and MTHFR gene variant was present in 8 subjects (P = 0.185). A combination of both gene variants were present in seven subjects, which was an interesting finding. In Group B, four subjects tested positive for the TGF-α and MTHFR gene variants. The TGF-α gene variant and a combination of TGF-α + MTHFR gene variants significantly contribute to the development of nonsyndromic CL/P and can be considered as genetic markers for Indian population. The MTHFR gene variant, though a minor risk factor, cannot be considered as a genetic marker.

  12. Molecular genetic analysis in mild hyperhomocysteinemia: a common mutation in the methylenetetrahydrofolate reductase gene is a genetic risk factor for cardiovascular disease.

    PubMed Central

    Kluijtmans, L. A.; van den Heuvel, L. P.; Boers, G. H.; Frosst, P.; Stevens, E. M.; van Oost, B. A.; den Heijer, M.; Trijbels, F. J.; Rozen, R.; Blom, H. J.

    1996-01-01

    Mild hyperhomocysteinemia is an established risk factor for cardiovascular disease. Genetic aberrations in the cystathionine beta-synthase (CBS) and methylenetetrahydrofolate reductase (MTHFR) genes may account for reduced enzyme activities and elevated plasma homocysteine levels. In 15 unrelated Dutch patients with homozygous CBS deficiency, we observed the 833T-->C (I278T) mutation in 50% of the alleles. Very recently, we identified a common mutation (677C-->T; A-->V) in the MTHFR gene, which, in homozygous state, is responsible for the thermolabile phenotype and which is associated with decreased specific MTHRF activity and elevated homocysteine levels. We screened 60 cardiovascular patients and 111 controls for these two mutations, to determine whether these mutations are risk factors for premature cardiovascular disease. Heterozygosity for the 833T-->C mutation in the CBS gene was observed in one individual of the control group but was absent in patients with premature cardiovascular disease. Homozygosity for the 677C-->T mutation in the MTHFR gene was found in (15%) of 60 cardiovascular patients and in only 6 (approximately 5%) of 111 control individuals (odds ratio 3.1 [95% confidence interval 1.0-9.2]). Because of both the high prevalence of the 833T-->C mutation among homozygotes for CBS deficiency and its absence in 60 cardiovascular patients, we may conclude that heterozygosity for CBS deficiency does not appear to be involved in premature cardiovascular disease. However, a frequent homozygous mutation in the MTHFR gene is associated with a threefold increase in risk for premature cardiovascular disease. PMID:8554066

  13. Complete deficiency of methylenetetrahydrofolate reductase in mice is associated with impaired retinal function and variable mortality, hematological profiles, and reproductive outcomes.

    PubMed

    Lawrance, Andrea K; Racine, Julie; Deng, Liyuan; Wang, Xiaoling; Lachapelle, Pierre; Rozen, Rima

    2011-02-01

    Severe deficiency of methylenetetrahydrofolate reductase (MTHFR) with homocystinuria can result in early demise or later-onset neurological impairment, including developmental delay, motor dysfunction, and seizures. We previously characterized BALB/c Mthfr (-/-)mice as a model for this disorder and have recently backcrossed the disrupted allele onto the C57Bl/6 background to examine the variable phenotypes in MTHFR deficiency. Compared with BALB/c Mthfr (-/-)mice, C57Bl/6 Mthfr (-/-)mice have enhanced survival rates (81% vs 26.5%). Four-day-old BALB/c mutant pups had lower body, brain, and spleen weights relative to their wild-type counterparts compared with C57Bl/6 mutants. Pregnant BALB/c Mthfr (+/-)mice had increased resorptions and embryonic delays compared with wild-type littermates, whereas these outcomes in C57Bl/6 c Mthfr (+/-)mice were similar to those of wild-type C57Bl/6 mice. BALB/c-mutant pups had altered hematological profiles (higher hematocrit, hemoglobin, and white blood cell counts, with lower platelet counts) compared with C57Bl/6 mutants. Mutants of both strains had similar degrees of hepatic steatosis, hepatic activity of betaine:homocysteine methyltransferase, and altered cerebellar histology. Electroretinograms (ERG) in C57Bl/6 Mthfr (-/-)mice revealed decreased amplitude of scotopic and photopic waves in 6-week-old mice, with normalized ERGs at 13 weeks. Plasma homocysteine was modestly higher in C57Bl/6 compared with BALB/c mice. Our results emphasize the variable presentation of MTHFR deficiency in different genetic backgrounds and suggest that plasma homocysteine is not a predictor of severity. In addition, our novel findings of decreased spleen weights, thrombocytopenia, and impaired retinal function warrant investigation in patients with severe MTHFR deficiency or other forms of homocystinuria.

  14. The "thermolabile" variant of methylenetetrahydrofolate reductase and neural tube defects: An evaluation of genetic risk and the relative importance of the genotypes of the embryo and the mother.

    PubMed Central

    Shields, D C; Kirke, P N; Mills, J L; Ramsbottom, D; Molloy, A M; Burke, H; Weir, D G; Scott, J M; Whitehead, A S

    1999-01-01

    Recent reports have implicated the "thermolabile" (T) variant of methylenetetrahydrofolate reductase (MTHFR) in the causation of folate-dependent neural tube defects (NTDs). We report herein the largest genetic study of NTD cases (n=271) and families (n=218) to date, establishing that, in Ireland, the "TT" genotype is found in 18.8% of cases versus 8.3% of controls (odds ratio 2.57; confidence interval [CI] 1.48-4.45; P=.0005). The maternal and paternal TT genotypes have intermediate frequencies of 13.8% and 11.9%, respectively, indicating that the predominant MTHFR-related genetic effect acts via the TT genotype of the developing embryo. Analysis of the 218 family triads of mother, father, and affected child with log-linear models supports this interpretation, providing significant evidence that the case TT genotype is associated with NTDs (P=.02) but no evidence of a maternal TT genotypic effect (P=. 83). The log-linear model predicted that the risk of NTDs conferred by the case TT genotype is 1.61 (CI 1.06-2.46), consistent with the paramount importance of the case TT genotype in determining risk. There is no compelling evidence for more than a modest additional risk conferred by a maternal TT genotype. These results favor a biological model of MTHFR-related NTD pathogenesis in which suboptimal maternal folate status imposes biochemical stress on the developing embryo, a stress it is ill-equipped to tolerate if it has a TT genotype. PMID:10090889

  15. Methylenetetrahydrofolate Reductase Variants Associated with Hypertension and Cardiovascular Disease Interact with Dietary Polyunsaturated Fatty Acids to Modulate Plasma Homocysteine in Puerto Rican Adults123

    PubMed Central

    Huang, Tao; Tucker, Katherine L.; Lee, Yu-Chi; Crott, Jimmy W.; Parnell, Laurence D.; Shen, Jian; Smith, Caren E.; Ordovas, Jose M.; Li, Duo; Lai, Chao-Qiang

    2011-01-01

    Although methylenetetrahydrofolate reductase (MTHFR) genetic variants are associated with plasma homocysteine (Hcy) and cardiovascular disease (CVD), little is known whether dietary fatty acid intake modulates these associations. The goal was to examine the interaction of MTHFR variants with dietary fatty acids influencing plasma Hcy in 995 Boston Puerto Rican adults. We found that plasma Hcy concentration was negatively correlated with (n-3) PUFA intake (r = −0.117; P = 0.022), and the ratio of (n-3):(n-6) PUFA in the diet (r = −0.122; P = 0.009). Further, 2 functional MTHFR variants, 1298A>C and 677C>T, which are not in linkage disequilibrium in this population, were significantly associated with hypertension (OR = 1.72, P = 0.024, and OR = 1.60, P = 0.002, respectively). In addition, the 1298A>C variant was significantly associated with CVD (OR = 3.32; P = 0.030). Importantly, this variant exhibited significant interactions with intakes of total and (n-6) PUFA and the (n-3):(n-6) PUFA ratio of the diet. The plasma Hcy concentration of carriers of risk allele 1298C was greater than that of noncarriers only when participants had consumed a high-PUFA diet (>7.8% energy) but was not greater when they had low intake of PUFA (≤7.8% energy). In addition, participants with combined genotypes of both SNP (677 TT with 1298 AC or CC) who consumed high levels of (n-3) PUFA (>0.66% energy) had lower plasma Hcy compared with those who had the same genotype and consumed low levels of (n-3) PUFA (≤0.66% energy). Our study suggests that dietary PUFA intake modulates the effect of 2 MTHFR variants on plasma Hcy in Boston Puerto Rican adults. PMID:21270364

  16. Methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and G1793A genotypes, and the relationship between maternal folate intake, tibia lead and infant size at birth

    PubMed Central

    Kordas, Katarzyna; Ettinger, Adrienne S.; Lamadrid-Figueroa, Héctor; Tellez-Rojo, Martha M.; Hérnandez-Avila, Mauricio; Hu, Howard; Wright, Robert O.

    2011-01-01

    Small size at birth continues to be a problem worldwide and many factors, including reduced folate intake and Pb exposure, are associated with it. However, single factors rarely explain the variability in birth weight, suggesting a need for more complex explanatory models. We investigated environment–gene interactions to understand whether folate intake and maternal Pb exposure were associated with smaller newborn size in 474 women with uncomplicated pregnancies delivering term infants in Mexico City. We examined if folate intake modified the negative effects of maternal Pb burden on birth size. We also asked if maternal and infant methylenetetrahydrofolate reductase (MTHFR) genotypes (C677T, A1298C and G1793A) modified the effects of folate intake or Pb exposure on birth size. Women were aged 24·6 (SD 5·1) years; 43·5 % were primiparous. Maternal blood Pb at delivery was 86 (SD 42) μg/l, with 26·7 % having levels ≥100 μg/l. Tibia Pb level was 9·9 (SD 9·8) μg/g. Of the women, 35·3 % had folate intakes <400 μg/d. Birth weight was 3170 (SD 422) g. In covariate-adjusted regressions, higher folate intake was associated with higher birth weight (β 0·04; P<0·05). Higher bone Pb was associated with lower birth weight (β −4·9; P<0·05). Folate intake did not modify the effects of Pb on birth size, nor did MTHFR modify the association between Pb or folate intake on birth size. Although modest, the relationship between maternal nutrition, Pb burden and birth size does underscore the importance of environmental exposures to child health because patterns of fetal growth may affect health outcomes well into adulthood. PMID:19338708

  17. Genetic Variation of Methylenetetrahydrofolate Reductase (MTHFR) and Thymidylate Synthase (TS) Genes Is Associated with Idiopathic Recurrent Implantation Failure

    PubMed Central

    Shim, Sung Han; Lee, Yubin; Kim, Ji Hyang; Jeon, Young Joo; Ko, Jung Jae; Lee, Woo Sik; Kim, Nam Keun

    2016-01-01

    The one-carbon metabolism pathway disorder was important role in successful pregnancy. The MTHFR and TS protein were crucial factor in one-carbon metabolism. To investigate the association between recurrent implantation failure (RIF) and enzymes in the one-carbon metabolism pathway. A total of 120 women diagnosed with RIF and 125 control subjects were genotyped for MTHFR 677C>T, 1298A>C, TSER 2R/3R and TS 1494del/ins by a polymerase chain reaction-restriction fragment length polymorphism assay. According to the gene-gene combination analysis, the MTHFR 677/MTHFR 1298 (TT/AA) and MTHFR 677/TS 1494 (TT/6bp6bp) genetic combinations were associated with relatively higher risks [adjusted odds ratio (AOR), 2.764; 95% CI, 1.065–7.174; P = 0.037 and AOR, 3.186; 95% CI, 1.241–8.178; P = 0.016] in RIF patients compared to the CC/AA (MTHFR 677/MTHFR 1298) and TT/6bp6bp (MTHFR 677/TS 1494) combinations, respectively. The results suggested that the combined MTHFR 677/MTHFR 1298 genotype might be associated with increased risk of RIF. To the best of our knowledge, this study is the first to elucidate the potential association of MTHFR, TS and TSER polymorphisms with RIF risk in Korean patients. PMID:27560137

  18. Genetic Variation of Methylenetetrahydrofolate Reductase (MTHFR) and Thymidylate Synthase (TS) Genes Is Associated with Idiopathic Recurrent Implantation Failure.

    PubMed

    Choi, Youngsok; Kim, Jung Oh; Shim, Sung Han; Lee, Yubin; Kim, Ji Hyang; Jeon, Young Joo; Ko, Jung Jae; Lee, Woo Sik; Kim, Nam Keun

    2016-01-01

    The one-carbon metabolism pathway disorder was important role in successful pregnancy. The MTHFR and TS protein were crucial factor in one-carbon metabolism. To investigate the association between recurrent implantation failure (RIF) and enzymes in the one-carbon metabolism pathway. A total of 120 women diagnosed with RIF and 125 control subjects were genotyped for MTHFR 677C>T, 1298A>C, TSER 2R/3R and TS 1494del/ins by a polymerase chain reaction-restriction fragment length polymorphism assay. According to the gene-gene combination analysis, the MTHFR 677/MTHFR 1298 (TT/AA) and MTHFR 677/TS 1494 (TT/6bp6bp) genetic combinations were associated with relatively higher risks [adjusted odds ratio (AOR), 2.764; 95% CI, 1.065-7.174; P = 0.037 and AOR, 3.186; 95% CI, 1.241-8.178; P = 0.016] in RIF patients compared to the CC/AA (MTHFR 677/MTHFR 1298) and TT/6bp6bp (MTHFR 677/TS 1494) combinations, respectively. The results suggested that the combined MTHFR 677/MTHFR 1298 genotype might be associated with increased risk of RIF. To the best of our knowledge, this study is the first to elucidate the potential association of MTHFR, TS and TSER polymorphisms with RIF risk in Korean patients.

  19. [C677T polymorphism of the methylentetrahydrofolate reductase gene in mothers of children affected with neural tube defects].

    PubMed

    Morales de Machín, Alisandra; Méndez, Karile; Solís, Ernesto; Borjas de Borjas, Lisbeth; Bracho, Ana; Hernández, María Luisa; Negrón, Aimara; Delgado, Wilmer; Sánchez, Yanira

    2015-09-01

    Neural tube defects (NTD) are the most common congenital anomalies of the central nervous system, with a multifactorial pattern of inheritance, presumably involving the interaction of several genetic and environmental factors. The methylenetetrahydrofolate reductase (MTHFR) gene 677C>T polymorphism has been implicated as a risk factor for NTD. The main objective of this research was to investigate the association of the 677C>T polymorphism of the MTHFR gene as a genetic risk factor for NTD. Molecular analysis was performed in DNA samples from 52 mothers with antecedent of NTD offspring and from 119 healthy control mothers. Using the Polymerase Chain Reaction, a 198 bases pairs fragment was digested with the restriction enzyme Hinfi. 677T MTHFR allele frequencies for the problem and the control groups were 51.92% and 34.45%, respectively, and 677C MTHFR allele frequencies were 48.08% and 65.55%, respectively. There were significant differences in allele (p: 0.002) and genotype (p: 0.007) frequencies between these two groups. The odds ratio (OR) to the TT genotype vs. the CC genotype was estimated as OR: 4.9 [95% CI: 1,347-6.416] p: 0.002; CT+TT vs. CC: OR: 2.9 [95% CI: 1.347-6.416] p: 0.005; TT vs. CT+CC: OR: 2.675 [95% CI: 1,111-6.441] p: 0.024. The data presented in this study support the relationship between MTHFR 677C>T polymorphism and risk in mothers with antecedent of NTD offspring.

  20. Regulation of Folate-Mediated One-Carbon Metabolism by Glycine N-Methyltransferase (GNMT) and Methylenetetrahydrofolate Reductase (MTHFR).

    PubMed

    Wang, Yi-Cheng; Wu, Ming-Tsung; Lin, Yan-Jun; Tang, Feng-Yao; Ko, Hsin-An; Chiang, En-Pei

    2015-01-01

    Folate-mediated one-carbon metabolism is an important therapeutic target of human diseases. We extensively investigated how gene-nutrient interactions may modulate human cancer risk in 2 major folate metabolic genes, MTHFR and GNMT. The biochemical impacts of MTHFR and GNMT on methyl group supply, global DNA methylation, nucleotide biosynthesis, DNA damage, and partitioning of the folate dependent 1-carbon group were carefully studied. The distinct model systems used included: EB virus-transformed lymphoblasts expressing human MTHFR polymorphic genotypes; liver-derived GNMT-null cell-lines with and without GNMT overexpression; and HepG2 cells with stabilized inhibition of MTHFR using shRNA, GNMT wildtype, heterozygotous (GNMT(het)) and knockout (GNMT(nul)) mice. We discovered that the MTHFR TT genotype significantly reduces folate-dependent remethylation under folate restriction, but it assists purine synthesis when folate is adequate. The advantage of de novo purine synthesis found in the MTHFR TT genotype may account for the protective effect of MTHFR in human hematological malignancies. GNMT affects transmethylation kinetics and S-adenosylmethionine (adoMet) synthesis, and facilitates the conservation of methyl groups by limiting homocysteine remethylation fluxes. Restoring GNMT assists methylfolate-dependent reactions and ameliorates the consequences of folate depletion. GNMT expression in vivo improves folate retention and bioavailability in the liver. Loss of GNMT impairs nucleotide biosynthesis. Over-expression of GNMT enhances nucleotide biosynthesis and improves DNA integrity by reducing uracil misincorporation in DNA both in vitro and in vivo. The systematic series of studies gives new insights into the underlying mechanisms by which MTHFR and GNMT may participate in human tumor prevention.

  1. [Association between methylenetetrahydrofolate reductase gene haplotypes and the susceptibility of chromosomal damage in coke-oven workers].

    PubMed

    Sun, Yao-feng; Dai, Yu-fei; Cheng, Juan; Leng, Shu-guang

    2006-07-01

    To investigate the association between MTHFR gene variances and chromosomal damage levels in peripheral blood lymphocyte in coke-oven workers exposed to polycyclic aromatic hydrocarbons (PAHs). One-hundred and forty coke-oven workers who exposed to a high level of PAHs and sixty-six non-exposed controls were selected as the study subjects. Chromosomal damage in peripheral lymphocyte was measured by the cytokinesis-block micronucleus (CBMN) assay. Urinary 1-hydroxypyrene (1-OHP) levels were measured as the internal dose of PAHs exposure. Two single nucleotide polymorphisms(SNPs) in MTHFR gene, including C677T, A1298C were detected by PCR-RFLP. The MTHFR haplotypes were estimated by Bayesian statistical method with the software of PHASE Version 2.1. The associations between haplotype pairs and CBMN were assessed by analysis of covariance in the coke-oven workers and controls. The variant allele frequencies for MTHFRC677T and A1298C were 0.56 and 0.16 respectively, which consistent with Hardy-Weinberg equilibrium. There was linkage disequilibrium between the two SNPs (D' = 0.99) in this study. Four haplotypes were calculated by PHASE, in terms of 677T - 1298A, 677C-1298A, 677C-1298C and 677T-1298C, the frequencies were 0.555,0.279,0.163 and 0.003 respectively. In coke-oven workers, the frequencies of total micronucleus of non-677C-1298A/677C-1298A haplotype pair was significantly higher than 677C-1298A/677C-1298A (1.00 +/- 0.67 vs 0.60 +/- 0.41, P = 0.04). The frequencies of total micronucleus of 677T-1298A/677T-1298A haplotype pair was significantly higher than 677C-1298A/677C-1298A (1.08 +/- 0.71 vs 0.60 +/- 0.41, P = 0.04). In coke-oven workers, the frequencies of total micronucleus among the different SNPs were not significant differences, either in the controls. The haplotypes of MTHFR gene might be one genetic susceptibility factors of PAH induced chromosomal damage in coke-oven workers.

  2. Fundamental Role of Methylenetetrahydrofolate Reductase 677 C → T Genotype and Flavin Compounds in Biochemical Phenotypes for Schizophrenia and Schizoaffective Psychosis

    PubMed Central

    Fryar-Williams, Stephanie

    2016-01-01

    The Mental Health Biomarker Project (2010–2016) explored variables for psychosis in schizophrenia and schizoaffective disorder. Blood samples from 67, highly characterized symptomatic cases and 67 gender and age matched control participants were analyzed for methyl tetrahydrofolate reductase (MTHFR) 677C → T gene variants and for vitamin B6, B12 and D, folate, unbound copper, zinc cofactors for enzymes in the methylation cycle, and related catecholamine pathways. Urine samples were analyzed for indole-catecholamines, their metabolites, and oxidative-stress marker, hydroxylpyrolline-2-one (HPL). Rating scales were Brief Psychiatric Rating Scale, Positive and Negative Syndrome Scale, Global Assessment of Function scale, Clinical Global Impression (CGI) score, and Social and Occupational Functioning Assessment Scale (SOFAS). Analysis used Spearman’s correlates, receiver operating characteristics and structural equation modeling (SEM). The correlative pattern of variables in the overall participant sample strongly implicated monoamine oxidase (MAO) enzyme inactivity so the significant role of MAO’s cofactor flavin adenine nucleotide and its precursor flavin adenine mononucleotide (FMN) within the biochemical pathways was investigated and confirmed as 71% on SEM of the total sample. Splitting the data sets for MTHFR 677C → T polymorphism variants coding for the MTHFR enzyme, discovered that biochemistry variables relating to the wild-type enzyme differed markedly in pattern from those coded by the homozygous variant and that the hereozygous-variant pattern resembled the wild-type-coded pattern. The MTHFR 677C → T-wild and -heterozygous gene variants have a pattern of depleted vitamin cofactors characteristic of flavin insufficiency with under-methylation and severe oxidative stress. The second homozygous MTHFR 677TT pattern related to elevated copper:zinc ratio and a vitamin pattern related to flavin sufficiency and risk of over-methylation. The

  3. Prothrombin G20210A and methylenetetrahydrofolate reductase C677T polymorphisms in peripheral capillary nonperfusion: a case report.

    PubMed

    Wathek, Chaima; Mrad, Meriem; Abdessalem, Nadia Ben; Maalej, Afef; Gritli, Nasreddine; Gabsi, Salem; Rannen, Riadh; Fekih-Mrissa, Najiba

    2015-09-01

    The G20210A mutation in the prothrombin gene is an established risk factor for venous thrombosis. However, there is some controversy as to the role played by this mutation in arterial thrombotic disease. The association of peripheral capillary nonperfusion with prothrombin G20210A mutation has never been reported before. We present the case of 34-year-old man who presented with peripheral capillary nonperfusion. The fundus examination of his right eye revealed an epiretinal membrane, peripheral (mainly temporally) retinal haemorrhages, exudates and microaneurismal alterations of the vascular bed. Fluorescein angiography of his right eye demonstrated an extended area of capillary nonperfusion distal to the microaneurismal lesions. Evaluation revealed mutations of the G20210A prothrombin and MTHFR genes. Screening for hereditary thrombophilia should be considered, regardless of patient age, in patients with peripheral retinal ischemia. The prothrombin G20210A mutation, a genetic risk factor, may be associated with peripheral capillary nonperfusion.

  4. Structures of NADH and CH[subscript 3]-H[subscript 4] Folate Complexes of Escherichia coli Methylenetetrahydrofolate Reductase Reveal a Spartan Strategy for a Ping-Pong Reaction

    SciTech Connect

    Pejchal, Robert; Sargeant, Ryan; Ludwig, Martha L.

    2010-03-08

    Methylenetetrahydrofolate reductases (MTHFRs; EC 1.7.99.5) catalyze the NAD(P)H-dependent reduction of 5,10-methylenetetrahydrofolate (CH{sub 2}-H{sub 4}folate) to 5-methyltetrahydrofolate (CH{sub 3}-H{sub 4}folate) using flavin adenine dinucleotide (FAD) as a cofactor. The initial X-ray structure of Escherichia coli MTHFR revealed that this 33-kDa polypeptide is a ({beta}{alpha}){sub 8} barrel that aggregates to form an unusual tetramer with only 2-fold symmetry. Structures of reduced enzyme complexed with NADH and of oxidized Glu28Gln enzyme complexed with CH{sub 3}-H{sub 4}folate have now been determined at resolutions of 1.95 and 1.85 {angstrom}, respectively. The NADH complex reveals a rare mode of dinucleotide binding; NADH adopts a hairpin conformation and is sandwiched between a conserved phenylalanine, Phe223, and the isoalloxazine ring of FAD. The nicotinamide of the bound pyridine nucleotide is stacked against the si face of the flavin ring with C4 adjoining the N5 of FAD, implying that this structure models a complex that is competent for hydride transfer. In the complex with CH{sub 3}-H{sub 4}folate, the pterin ring is also stacked against FAD in an orientation that is favorable for hydride transfer. Thus, the binding sites for the two substrates overlap, as expected for many enzymes that catalyze ping-pong reactions, and several invariant residues interact with both folate and pyridine nucleotide substrates. Comparisons of liganded and substrate-free structures reveal multiple conformations for the loops {beta}2-{alpha}2 (L2), {beta}3-{alpha}3 (L3), and {beta}4-{alpha}4 (L4) and suggest that motions of these loops facilitate the ping-pong reaction. In particular, the L4 loop adopts a 'closed' conformation that allows Asp120 to hydrogen bond to the pterin ring in the folate complex but must move to an 'open' conformation to allow NADH to bind.

  5. [The C677T polymorphism in the methylene tetrahydrofolate reductase gene among Tunisian population].

    PubMed

    Jerbi, Z; Abdennebi, M; Douik, H; Ben Romdhane, H; Harzallah, L; Guemira, F; Ghanem, A

    2005-01-01

    The 5,10 methylene tetrahydrofolate reductase (MTHFR) is an enzyme that catalyzes the irreversible reduction of 5,10 methylene tetrahydrofolate into 5 methyl tetrahydrofolate. It is coded by a gene where several polymorphisms have been identified. The most common is the C677T polymorphism described as presenting an heterogeneous worldwide distribution and associated with different disorders such as cardiovascular and cancerous diseases. The aim of this work was to determine the allelic and genotypic frequencies of the C677T polymorphism among a Tunisian healthy population. The study concerned 185 subjects apparently healthy. It was carried out by the PCR/RFLP method, using the restriction enzyme Hinf I. The results has showed an allelic frequency of 17.8% with a genotype frequency of 5.4%. These values are intermediate between those observed in Africa and those observed in Western countries. They must be considered in the evaluation of the clinic significance of a predisposition to diseases.

  6. [Vascular diseases, spina bifida and schizophrenia in a single family associated with the heterozygote mutation of the heat-sensitive variant of methylenetetrahydrofolate reductase].

    PubMed

    Horváth, A; Morava, E; Tóth, G; Czakó, M; Melegh, B; Kosztolányi, G

    2001-07-08

    Homozygous mutation of the thermolabile variant of methylene tetrahydrofolate reductase (MTHFR) may result in hyperhomocystinemia, leading to an increased risk for early cardiovascular disease, neural tube defects, and possibly major depression, schizophrenia. According to recent studies heterozygosity for the thermolabile variant of the MTHFR gene mutation is also more frequent in patients with thrombotic disease compared to that in the average population. We report on a family with different types of early vascular disease. In four consecutive generations MTHFR heterozygosity was detected: in the proband and in her mother, grandfather and daughter. Further conditions of the family members, possibly due to carrying the mutation, came to light by the pedigree analysis and examinations. The patient had pulmonary emboli at young age, her aunt died of spina bifida shortly after birth. The patient's mother suffers from schizophrenia and depression. The grandfather had pulmonary emboli, her sister with spina bifida occulta also carries the same mutation, as does her daughter who is sofar asymptomatic. In other asymptomatic members of the family no mutations were found. Unexpectedly, hyperhomocystinemia was detected in all heterozygote individuals. Our study demonstrates the necessity for folic acid therapy in mutation carriers to prevent early vascular events, depression and schizophrenia, and also to reduce the risk for neural tube defects in a preconception setting.

  7. Genetic variation in Glutathione S-Transferase Omega-1, Arsenic Methyltransferase and Methylene-tetrahydrofolate Reductase, arsenic exposure and bladder cancer: a case–control study

    PubMed Central

    2012-01-01

    Background Ingestion of groundwater with high concentrations of inorganic arsenic has been linked to adverse health outcomes, including bladder cancer, however studies have not consistently observed any elevation in risk at lower concentrations. Genetic variability in the metabolism and clearance of arsenic is an important consideration in any investigation of its potential health risks. Therefore, we examined the association between genes thought to play a role in the metabolism of arsenic and bladder cancer. Methods Single nucleotide polymorphisms (SNPs) in GSTO-1, As3MT and MTHFR were genotyped using DNA from 219 bladder cancer cases and 273 controls participating in a case–control study in Southeastern Michigan and exposed to low to moderate (<50 μg/L) levels of arsenic in their drinking water. A time-weighted measure of arsenic exposure was constructed using measures from household water samples combined with past residential history, geocoded and merged with archived arsenic data predicted from multiple resources. Results While no single SNP in As3MT was significantly associated with bladder cancer overall, several SNPs were associated with bladder cancer among those exposed to higher arsenic levels. Individuals with one or more copies of the C allele in rs11191439 (the Met287Thr polymorphism) had an elevated risk of bladder cancer (OR = 1.17; 95% CI = 1.04-1.32 per 1 μg/L increase in average exposure). However, no association was observed between average arsenic exposure and bladder cancer among TT homozygotes in the same SNP. Bladder cancer cases were also 60% less likely to be homozygotes for the A allele in rs1476413 in MTHFR compared to controls (OR = 0.40; 95% CI = 0.18-0.88). Conclusions Variation in As3MT and MTHFR is associated with bladder cancer among those exposed to relatively low concentrations of inorganic arsenic. Further investigation is warranted to confirm these findings. PMID:22747749

  8. Analysis of methionine synthase reductase polymorphism (A66G) in Indian Muslim population

    PubMed Central

    Rai, Vandana; Yadav, Upendra; Kumar, Pradeep; Yadav, Sushil Kumar

    2013-01-01

    BACKGROUND AND OBJECTIVES: Methionine synthase reductase (MTRR) is a vital enzyme of homocysteine/methionine metabolic pathway and is required for the conversion of inactive form of methionine synthase (MTR) to its active form. A clinically important allelic variant of MTRR A66G, with less enzymatic activity is reported with worldwide prevalence rate of ~ 30%. The present study was designed to determine the frequency of MTRR A66G polymorphism in rural Sunni Muslim population of Eastern Uttar Pradesh. MATERIALS AND METHODS: Total 56 subjects were analyzed for MTRR A66G polymorphism. A66G mutation analysis was carried out according to the polymerase chain reaction-restriction fragment length polymorphism method of Wilson et al. [1] amplification with MTRR specific primers followed by amplicon digestion with NdeI enzyme was used for the identification of different MTRR genotypes in subjects. RESULTS AND DISCUSSION: The AA genotype was found in 5 subjects, AG in 23 subjects, and GG genotype in 28 subjects. Genotype frequencies of AA, AG, and GG were 0.089, 0.41, and 0.5 respectively. The allele frequency of A allele was found to be 0.298 and G allele was 0.705. CONCLUSION: It is evident from the present study that the percentage of homozygous genotype GG and frequency of G allele is high in the target Muslim population. PMID:24019620

  9. Malaria antifolate resistance with contrasting Plasmodium falciparum dihydrofolate reductase (DHFR) polymorphisms in humans and Anopheles mosquitoes

    PubMed Central

    Mharakurwa, Sungano; Kumwenda, Taida; Mkulama, Mtawa A. P.; Musapa, Mulenga; Chishimba, Sandra; Shiff, Clive J.; Sullivan, David J.; Thuma, Philip E.; Liu, Kun; Agre, Peter

    2011-01-01

    Surveillance for drug-resistant parasites in human blood is a major effort in malaria control. Here we report contrasting antifolate resistance polymorphisms in Plasmodium falciparum when parasites in human blood were compared with parasites in Anopheles vector mosquitoes from sleeping huts in rural Zambia. DNA encoding P. falciparum dihydrofolate reductase (EC 1.5.1.3) was amplified by PCR with allele-specific restriction enzyme digestions. Markedly prevalent pyrimethamine-resistant mutants were evident in human P. falciparum infections—S108N (>90%), with N51I, C59R, and 108N+51I+59R triple mutants (30–80%). This resistance level may be from selection pressure due to decades of sulfadoxine/pyrimethamine use in the region. In contrast, cycloguanil-resistant mutants were detected in very low frequency in parasites from human blood samples—S108T (13%), with A16V and 108T+16V double mutants (∼4%). Surprisingly, pyrimethamine-resistant mutants were of very low prevalence (2–12%) in the midguts of Anopheles arabiensis vector mosquitoes, but cycloguanil-resistant mutants were highly prevalent—S108T (90%), with A16V and the 108T+16V double mutant (49–57%). Structural analysis of the dihydrofolate reductase by in silico modeling revealed a key difference in the enzyme within the NADPH binding pocket, predicting the S108N enzyme to have reduced stability but the S108T enzyme to have increased stability. We conclude that P. falciparum can bear highly host-specific drug-resistant polymorphisms, most likely reflecting different selective pressures found in humans and mosquitoes. Thus, it may be useful to sample both human and mosquito vector infections to accurately ascertain the epidemiological status of drug-resistant alleles. PMID:22065788

  10. Plasma homocysteine levels, methylene tetrahydrofolate reductase polymorphisms, and the risk of thromboembolism in children.

    PubMed

    Nahar, Akash; Sabo, Cynthia; Chitlur, Meera; Ravindranath, Yaddanapudi; Lusher, Jeanne; Rajpurkar, Madhvi

    2011-07-01

    Hyperhomocystenemia (HHcy) is a risk factor for thrombosis in adults. Polymorphisms in methylene tetrahydrofolate reductase (MTHFR) enzyme may cause HHcy. Data on their role in pediatric thromboembolism (TE) are sparse. Charts of patients from 1989 to 2007, with documented TE, were reviewed. Homocysteine (Hcy) levels were defined both as per the adult normal range and the age-specific normal ranges from literature. A total of 141 patients (67 females, 74 males) were identified. With age-specific normal ranges for Hcy, 15 patients were found to have HHcy: 6 had CT, 9 patients had CC, and none had TT MTHFR genotype. When adult normal range was used, HHcy (>12 μmol/L) was seen in 7 patients: 4 had CT and 3 had the CC genotype. Again, none had TT genotype. In addition, the mean Hcy levels were unaffected by sex and ethnicities, but universal folic acid supplementation (post 1996) lowered the mean. (1) Age-specific ranges for Hcy should be used in pediatrics for accurate diagnosis of HHcy. (2) MTHFR C677T polymorphism is not a risk factor in pediatric TE. (3) Folic acid supplementation could play a role in lowering the prevalence of HHcy.

  11. Human Aldo-Keto Reductases: Function, Gene Regulation, and Single Nucleotide Polymorphisms

    PubMed Central

    Penning, Trevor M.; Drury, Jason E.

    2007-01-01

    Aldo-Keto Reductases (AKRs) are a superfamily of NAD(P)H linked oxidoreductases that are generally monomeric 34- 37 kDa proteins present in all phyla. The superfamily consists of 15 families, which contains 151 members (www.med.upenn.edu/akr). Thirteen human AKRs exist that use endogenous substrates (sugar and lipid aldehydes, prostaglandins, retinals and steroid hormones), and in many instances they regulate nuclear receptor signaling. Exogenous substrates include metabolites implicated in chemical carcinogenesis: NNK (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone), polycyclic aromatic hydrocarbon trans-dihydrodiols, and aflatoxin dialdehyde. Promoter analysis of the human genes identifies common elements involved in their regulation which include osmotic response elements, antioxidant response elements, xenobiotic response elements, AP-1 sites and steroid response elements. The human AKRs are highly polymorphic, and in some instances single nucleotide polymorphisms (SNPs) of high penetrance exist. This suggests that there will be inter-individual variation in endogenous and xenobiotic metabolism which in turn affect susceptibility to nuclear receptor signaling and chemical carcinogenesis. PMID:17537398

  12. The Drop That Spilled the Cup: Acute Myocardial Infarction in a Young Woman with Underlying Thrombophilic Polymorphisms and Oral Contraceptive Use

    PubMed Central

    Capilli, Gianfranco; Patané, Anella Antonietta

    2014-01-01

    We present the case of a 28-year-old woman who was admitted to our cardiology unit for acute coronary syndrome. Her history was notable for cardiovascular disease familiarity, active smoking, and oral contraceptive use. On further analysis, she was noted to have thrombophilic polymorphisms involving the plasminogen activator inhibitor (PAI), angiotensin-converting enzyme (ACE), and methylenetetrahydrofolate reductase (MTHFR) genes. We discuss the implications that these cofactors may have had in the genesis of the disease. PMID:25587456

  13. Survival and risk of relapse of acute lymphoblastic leukemia in a Mexican population is affected by dihydrofolate reductase gene polymorphisms

    PubMed Central

    GÓMEZ-GÓMEZ, YAZMÍN; ORGANISTA-NAVA, JORGE; SAAVEDRA-HERRERA, MÓNICA VIRGINIA; RIVERA-RAMÍREZ, ANA BERTHA; TERÁN-PORCAYO, MARCO ANTONIO; DEL CARMEN ALARCÓN-ROMERO, LUZ; ILLADES-AGUIAR, BERENICE; LEYVA-VÁZQUEZ, MARCO ANTONIO

    2012-01-01

    Dihydrofolate reductase (DHFR) is the major target of methotrexate, a key component in childhood acute lymphoblastic leukemia (ALL) treatment. Polymorphisms in the gene coding for DHFR have been associated with adverse event treatment. This study evaluated the effect of the -A317G and C829T polymorphisms in the DHFR gene on survival and risk of relapse of ALL. Seventy patients with ALL and 100 healthy individuals were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method. An association between the polymorphisms and the risk of relapse was found (p<0.05); patients with the -317G/G genotype were found to have an 8.55 (95% CI 1.84–39.70) higher chance of relapse and carriers of the 829T/T genotype had a 14.0 (95% CI 1.13–172.63) higher chance of relapse. Other variables, such as age and leukocyte count, were associated (p<0.05) with the risk of relapse of the disease. Individuals with the G/G and T/T genotype of the -A317G and C829T polymorphisms had poorer survival compared to other genotype groups (log-rank test; p<0.05). Although preliminary, these data seem to suggest a role for the DHFR polymorphisms in the risk of relapse of ALL and the mortality risk in these patients. PMID:22969948

  14. The methylenetetrahydrofolate reductase polymorphism (MTHFR c.677C>T) and elevated plasma homocysteine levels in a U.S. pediatric population with incident thromboembolism.

    PubMed

    Joachim, Emily; Goldenberg, Neil A; Bernard, Timothy J; Armstrong-Wells, Jennifer; Stabler, Sally; Manco-Johnson, Marilyn J

    2013-08-01

    Elevated plasma homocysteine (tHcy) and the MTHFR c.677C>T variant have been postulated to increase the risk of venous thromboembolism (VTE), although mechanisms and implications to pediatrics remain incompletely understood. The objectives of this study were to determine the prevalences of elevated tHcy and MTHFR variant in a pediatric population with VTE or arterial ischemic stroke (AIS), and to determine associations with thrombus outcomes. Subjects were enrolled in an institution-based prospective cohort of children with VTE or AIS. Inclusion criteria consisted of objectively confirmed thrombus, ≤21years at diagnosis, tHcy measured and MTHFR c.677C>T mutation analysis. Clinical and laboratory data were collected. Frequencies for elevated tHcy and MTHFR variant were compared with NHANES values for healthy US children and also between study groups (VTE vs AIS, provoked vs idiopathic) and by age. The prevalences of hyperhomocysteinemia or MTHFR variant were not increased in comparison to NHANES. tHcy did not differ between those with wild-type MTHFR versus either c.677C>T heterozygotes or homozygotes. There was no association between tHcy or MTHFR variant and thrombus outcomes. In this cohort of US children with VTE or AIS, neither the prevalence of hyperhomocysteinemia nor that of MTHFR variant was increased relative to reference values, and adverse thrombus outcomes were not definitively associated with either. While it is important to consider that milder forms of pyridoxine-responsive classical homocystinuria will be detected only by tHcy, we suggest that routine testing of MTHFR c.677C>T genotype as part of a thrombophilia evaluation in children with incident thromboembolism is not warranted until larger studies have been performed in order to establish or refute a link between MTHFR and adverse outcomes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Association of aldose reductase gene polymorphism (C-106T) in susceptibility of diabetic peripheral neuropathy among north Indian population.

    PubMed

    Gupta, Balram; Singh, S K

    2017-07-01

    Polymorphism in aldose reductase (ALR) gene at nucleotide C(-106)T (rs759853) in the promoter region is associated with susceptibility to development of diabetic peripheral neuropathy. The aim of this study was to detect the association of the C (-106)T polymorphism of ALR gene and its frequency among patients with type 2 diabetes mellitus with and without peripheral neuropathy. The study subjects were divided into three groups. Group I included 356 patients with diabetes having peripheral neuropathy. Group II included 294 patients with diabetes without peripheral neuropathy and group III included 181 healthy subjects. Genotyping of ALR C(-106)T SNPs was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing methods. The genetic risk among the groups was compared and tested by calculating odds ratio with 95% class interval. ALR 106TT genotype was significantly higher in group I compared to group II with an odds ratio of 2.12 (95% CI: 1.22-3.67; p<0.01). Recessive model (CC+CT vs. TT), as well as T allele distribution also showed significant association to develop neuropathy with relative risk of 1.97 (95% CI: 1.16-3.35; p<0.01) and 1.36 (95% CI: 1.07-1.72; p=0.01) respectively. In conclusion, the ALR C-106T polymorphism was associated with higher risk of peripheral neuropathy in patients with type 2 diabetes mellitus. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Adaptive developmental plasticity in methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism limits its frequency in South Indians.

    PubMed

    Naushad, Shaik Mohammad; Krishnaprasad, Chintakindi; Devi, Akella Radha Rama

    2014-05-01

    Methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism shows considerable heterogeneity in its distribution in humans worldwide. The current study was conducted to investigate whether this polymorphism exhibited adaptive developmental plasticity in the control of the TT-genotype frequency. We screened 1,818 South Indian subjects (895 males and 923 females) for MTHFR C677T polymorphism using PCR-restriction fragment length polymorphism approach. MTHFR 677T-allele frequency in males and females was 9.1 and 11.0%, respectively. Compared to females, males had lower frequency of TT-genotype [odds ratio 0.31, 95% confidence interval (CI) 0.08-1.01]. The frequency of MTHFR 677T-allele was highest in the age group of 20-40 years and it gradually decreased from 40-60 to 60-80 years (P trend<0.0001). MTHFR 677TT-genotype was associated with 7.02-folds (95% CI: 2.12-25.63, P<0.0001) cumulative risk for recurrent pregnancy loss (RPL), neural tube defects (NTDs) and deep vein thrombosis (DVT). Linear regression model suggested that male gender exhibited increased homocysteine levels by 9.35 μmol/L while each MTHFR 677T-allele contributed to 4.63 μmol/L increase in homocysteine. Plasma homocysteine showed inverse correlation with dietary folate (r=-0.17, P<0.0001), B2 (r=-0.14, P<0.0001) and B6 (r=-0.07, P=0.03). Examination of the spontaneously aborted fetuses (n=35) showed no significant association of fetal genotype on its in utero viability. From the current study, it was concluded that C677T seemed to have acquired adaptive developmental plasticity among South Indians due to environmental influences thus contributing to hyperhomocysteinemia and its associated complications such as RPL, NTDs, DVT, etc.

  17. Polymorphisms in Methionine Synthase Reductase and Betaine-Homocysteine S-Methyltransferase Genes: Risk of Placental Abruption

    PubMed Central

    Ananth, Cande V.; Elsasser, Denise; Kinzler, Wendy L.; Peltier, Morgan R.; Getahun, Darios; Leclerc, Daniel; Rozen, Rima R.

    2007-01-01

    Objective Methionine Synthase Reductase (MTRR) and Betaine-Homocysteine S-Methyltransferase (BHMT) are 2 enzymes that regulate homocysteine metabolism. Elevated homocysteine (hyperhomocysteinemia) is associated with adverse pregnancy outcomes and vascular disease. We assessed whether polymorphisms in MTRR (66A→G; I22M) and BHMT (742G→A; R239Q) were associated with abruption. We further evaluated whether homocysteine levels differed between cases and controls for MTRR and BHMT genotypes. Methods Data were derived from the New Jersey Placental Abruption Study (NJ-PAS)—an ongoing, multicenter, case-control study since August 2002. Women with a clinical diagnosis of abruption were recruited as incident cases (n=196), and controls (n=191) were matched to cases based on maternal race/ethnicity and parity. Total plasma homocysteine concentrations were evaluated in a subset of 136 cases and 136 controls. DNA was genotyped for the MTRR and BHMT polymorphisms. Results Frequencies of the minor allele of MTRR were 40.8% and 42.2% in cases and controls, respectively (adjusted OR 0.79, 95% CI 0.45, 1.40). The corresponding rates for BHMT were 33.9% and 31.7%, respectively (adjusted OR 1.93, 95% CI 0.99, 4.09). Distributions for the homozygous mutant form of MTRR were similar between cases and controls (OR 1.18, 95% CI 0.62, 2.24). The rate of homozygous mutant BHMT genotype was 2.8-fold (OR 2.82, 95% CI 1.84, 4.97) higher in cases than controls. Stratification of analyses based on maternal race did not reveal any patterns in association. Conclusions In this population, there was an association between the homozygous mutant form of BHMT (742G→A) polymorphism and increased risk for placental abruption. PMID:17376725

  18. Additive effect of aldose reductase Z-4 microsatellite polymorphism and glycaemic control on cataract development in type 2 diabetes.

    PubMed

    Wang, Ying; Luk, Andrea O Y; Ng, Maggie C Y; Pang, Calvin C P; Lam, Vincent; Lee, Shao C; Lam, Dennis S C; Choy, Kwong Wai; Ma, Ronald C W; So, Wing-Yee; Chan, Juliana C N

    2014-01-01

    To examine the additive effect of the z-4 microsatellite polymorphism of aldose reductase gene (ALR2) and glycaemic control on risk of cataract in a prospective cohort of Chinese type 2 diabetic patients. The (CA)n microsatellite polymorphism of ALR2 was determined using PCR followed by capillary gel electrophoresis. Cataract was defined by presence of lens opacity on direct ophthalmoscopy or history of cataract surgery. A non-linear curve approach was used to identify the threshold of glycated hemoglobin (HbA1c) at which the odds ratio (OR) for cataract started to increase. The association of z-4 allele with cataract, above and below this threshold, was assessed using multiple logistic regression analysis. Of the 5823 patients analyzed, 28.1% had cataracts. After adjusting for conventional risk factors and using non-z-4 carriers with HbA1c<8.0% as referent group (n = 3173), the OR (95% confidence intervals) for cataract was highest in z-4 carriers with HbA1c ≥ 8.0% [1.43 (1.05-1.96), n = 244], compared to non-z-4 carriers with HbA1c ≥ 8.0 [1.27 (1.10-1.47), n = 1836] and z-4 carriers with HbA1c<8.0%[1.01 (0.77-1.29), n = 420, P(trend) < 0.001]. This additive association remained significant after additional adjustments for drug use (P(trend) = 0.002) and renal function (P(trend) = 0.01). In type 2 diabetic patients with suboptimal glycaemic control, the z-4 allele of ALR2 (CA)n polymorphism was independently associated with increased susceptibility to cataracts. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. A common haplotype on methylenetetrahydrofolate reductase gene modifies the effect of angiotensin-converting enzyme inhibitor on blood pressure in essential hypertension patients--a family-based association study.

    PubMed

    Jiang, Shanqun; Hsu, Yi-Hsiang; Niu, Tianhua; Xu, Xin; Xing, Houxun; Chen, Changzhong; Wang, Xiaobin; Zhang, Yan; Peng, Shaojie; Xu, Xiping

    2005-08-01

    Our recent study indicated that MTHFR C677T polymorphism may involve in genetic control of blood pressure response to treatment by benazepril, an ACE inhibitor. Currently, we proposed to further investigate whether short-term blood pressure response to benazepril, was modulated by haplotypes re-constructed from both C677T and A1298C polymorphisms in MTHFR gene. A total of 410 hypertensive patients recruited from 344 nuclear families were treated orally with benazepril at a daily dosage of 10 mg for 15 consecutive days. Blood pressures were measured at baseline and on the 16th day of treatment. In addition, 689 family members of these patients were also genotyped. Among these patients, the frequency of MTHFR A1298C AA, AC and CC genotypes was 74.4%, 23.9%, and 1.7%, respectively. The frequency of MTHFR C677T CC, CT and TT genotypes was 23.7%, 51.2%, and 25.1%, respectively. Only three haplotypes, 677T-1298A (50.8%), 677C-1298A (35.7%), and 677C-1298C (13.5%) were re-constructed. Multivariate regression models with generalized estimating equation (GEE) correction detected that the individuals carrying one copy of haplotype 677C-1298C had significantly lower diastolic and systolic blood pressure response (DeltaDBP and DeltaSBP) to benazepril treatment (p= 0.003 and p =0.043, respectively), in comparison to those without haplotype 677C-1298C. The results of family-based association test further confirmed that haplotype 677C-1298C was more frequently transmitted in subjects with either lower residual of DeltaDBP or DeltaSBP. For residual of DeltaDBP, the p-values are 0.007 in an additive model and 0.005 in a dominant model. For residual of DeltaSBP, the p-values are 0.009 in an additive model and 0.006 in a dominant model. Our findings suggest that MTHFR 677C-1298C haplotype modulate blood pressure responsiveness to shortterm treatment of ACE inhibitor in Chinese essential hypertensive patients.

  20. Polymorphisms in thioredoxin reductase and selenoprotein K genes and selenium status modulate risk of prostate cancer.

    PubMed

    Méplan, Catherine; Rohrmann, Sabine; Steinbrecher, Astrid; Schomburg, Lutz; Jansen, Eugène; Linseisen, Jakob; Hesketh, John

    2012-01-01

    Increased dietary intake of Selenium (Se) has been suggested to lower prostate cancer mortality, but supplementation trials have produced conflicting results. Se is incorporated into 25 selenoproteins. The aim of this work was to assess whether risk of prostate cancer is affected by genetic variants in genes coding for selenoproteins, either alone or in combination with Se status. 248 cases and 492 controls from an EPIC-Heidelberg nested case-control study were subjected to two-stage genotyping with an initial screening phase in which 384 tagging-SNPs covering 72 Se-related genes were determined in 94 cases and 94 controls using the Illumina Goldengate methodology. This analysis was followed by a second phase in which genotyping for candidate SNPs identified in the first phase was carried out in the full study using Sequenom. Risk of high-grade or advanced stage prostate cancer was modified by interactions between serum markers of Se status and genotypes for rs9880056 in SELK, rs9605030 and rs9605031 in TXNRD2, and rs7310505 in TXNRD1. No significant effects of SNPs on prostate cancer risk were observed when grade or Se status was not taken into account. In conclusion, the risk of high-grade or advanced-stage prostate cancer is significantly altered by a combination of genotype for SNPs in selenoprotein genes and Se status. The findings contribute to explaining the biological effects of selenium intake and genetic factors in prostate cancer development and highlight potential roles of thioredoxin reductases and selenoprotein K in tumour progression.

  1. Polymorphisms in Thioredoxin Reductase and Selenoprotein K Genes and Selenium Status Modulate Risk of Prostate Cancer

    PubMed Central

    Méplan, Catherine; Rohrmann, Sabine; Steinbrecher, Astrid; Schomburg, Lutz; Jansen, Eugène; Linseisen, Jakob; Hesketh, John

    2012-01-01

    Increased dietary intake of Selenium (Se) has been suggested to lower prostate cancer mortality, but supplementation trials have produced conflicting results. Se is incorporated into 25 selenoproteins. The aim of this work was to assess whether risk of prostate cancer is affected by genetic variants in genes coding for selenoproteins, either alone or in combination with Se status. 248 cases and 492 controls from an EPIC-Heidelberg nested case-control study were subjected to two-stage genotyping with an initial screening phase in which 384 tagging-SNPs covering 72 Se-related genes were determined in 94 cases and 94 controls using the Illumina Goldengate methodology. This analysis was followed by a second phase in which genotyping for candidate SNPs identified in the first phase was carried out in the full study using Sequenom. Risk of high-grade or advanced stage prostate cancer was modified by interactions between serum markers of Se status and genotypes for rs9880056 in SELK, rs9605030 and rs9605031 in TXNRD2, and rs7310505 in TXNRD1. No significant effects of SNPs on prostate cancer risk were observed when grade or Se status was not taken into account. In conclusion, the risk of high-grade or advanced-stage prostate cancer is significantly altered by a combination of genotype for SNPs in selenoprotein genes and Se status. The findings contribute to explaining the biological effects of selenium intake and genetic factors in prostate cancer development and highlight potential roles of thioredoxin reductases and selenoprotein K in tumour progression. PMID:23133653

  2. Polymorphisms in folate-related enzyme genes in idiopathic infertile Brazilian men.

    PubMed

    Gava, Marcello M; Kayaki, Erika A; Bianco, Bianca; Teles, Juliana S; Christofolini, Denise M; Pompeo, Antonio C L; Glina, Sidney; Barbosa, Caio P

    2011-12-01

    The aim of the study was to analyze the distribution of the methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), and methionine synthase (MTR) polymorphisms in idiopathic infertile Brazilian men and fertile men. Case-control study comprising 133 idiopathic infertile Brazilian men with nonobstructive azoospermia ([NOA] n = 55) or severe oligozoospermia ([SO] n = 78) and 173 fertile men as controls. MTHFR C677T, A1298C, and G1793A; MTRR A66G; and MTR A2756G polymorphisms were studied by quantitative polymerase chain reaction (qPCR). The results were analyzed statistically and a P value <.05 was considered significant. Single-marker analysis revealed a significant association among MTHFR C677T polymorphism and both NOA group (P = .018) and SO group (P < .001). Considering the MTHFR A1298C, MTHFR G1793A, and MTRR A66G polymorphisms, no difference was found between NOA group and SO group. Regarding the MTR A2756G polymorphism, a significant difference was found between NOA and controls, P = .017. However, statistical analysis revealed no association between SO group and controls. Combined genotypes of 3 MTHFR polymorphisms did not identify a haplotype associated with idiopathic infertility. The combinatory analysis of the 3 polymorphisms MTHFR, MTRR, and MTR did not show difference between cases and controls. The findings suggest the MTHFR C677T and MTR A2756G polymorphisms could be an important genetic factor predisposing to idiopathic infertility in Brazilian men.

  3. [Analysis on correlation between 3-hydroxy-3-methylglutary-coenzyme A reductase gene polymorphism of Glycyrrhiza uralensis and content of glycyrrhizic acid].

    PubMed

    Liu, Ying; Xu, Qiao-Xian; Wang, Xue-Yong; Liu, Chun-Sheng; Chen, Hong-Hao

    2012-12-01

    To reveal the 3-hydroxy-3-methylglutary-coenzyme A reductase (HMGR) gene polymorphism of Glycyrrhiza uralensis, and the correlation between HMGR gene polymorphism and the content of glycyrrhizic acid. Liquorice plants containing different content of glycyrrhizic acid were used as materials. RT-PCR was used to amplify their HMGR gene sequences, which were connected with vector pMD19-T for clone sequencing. Multiple alignments were performed to analyse HMGR gene polymorphism of G. uralensis. Then the correlation between HMGR gene polymorphism and the content of glycyrrhizic acid was revealed. HMGR gene sequences polymorphism included codon mutation, base substitution mutation, copy number polymorphism and allele heterozygosity. There were 4 types of mutations in HMGR gene coding amino acid sequences, namely -HSL, -HSV, GALLV, GALSV. Among them, -HSV type was common in liquorice plants, -HSL type only existed in liquorice plants with low content of glycyrrhizic acid, and GALSV type only existed in liquorice plants with high content of glycyrrhizic acid. HMGR gene sequences of G. uralensis are highly polymorphic and related to the content of glycyrrhizic acid.

  4. Polymorphism C776G in the transcobalamin II gene and homocysteine, folate and vitamin B12 concentrations. Association with MTHFR C677T and A1298C and MTRR A66G polymorphisms in healthy children.

    PubMed

    Aléssio, Ana C M; Höehr, Nelci F; Siqueira, Lúcia H; Bydlowski, Sérgio P; Annichino-Bizzacchi, Joyce M

    2007-01-01

    One of the etiologies of hyperhomocysteinemia is decreased vitamin B(12). Genetic variation in the transcobalamin II gene, the transporter of vitamin B(12) to the cells, may produce altered homocysteine levels. We determined transcobalamin II C776G polymorphism, homocysteine, folate and vitamin B(12) levels and analyzed the interactive effect with the methylenetetrahydrofolate reductase C677T and A1298C and methionine synthase reductase A66G polymorphisms in 207 healthy Brazilian children. The prevalence of GG genotype of transcobalamin II C776G polymorphism in this Brazilian population, a highly miscigeneous population was 12.5% and the statistical analysis showed that this population is in Hardy-Weinberg equilibrium, it could be considered representative of the general population. We observed a significant increase in homocysteine in the 776GG vs. 776CC genotype, corroborating the influence of age as a determinant of homocysteine in relation to this polymorphism. When we analyzed vitamin B(12) and its relationship with the C776G polymorphism, we found no significant differences. Only 776CG/66AA or 776GG/66AG genotypes presented a significant increase in homocysteine when compared with other groups. In the multivariate analysis, transcobalamin II C776G (CC/CG vs. GG), methylenetetrahydrofolate reductase C677T (CC/CT vs. TT), folate, gender and age presented statistical significance in relation to the homocysteine. These can be considered independent risk factors for hyperhomocysteinemia in this children group. Our results, if confirmed in other populations, highlight the necessity for investigation of the transcobalamin II C776G polymorphism in the research for hyperhomocysteinemia risk factors.

  5. Analysis of Polymorphisms in Genes (AGT, MTHFR, GPIIIa, and GSTP1) Associated with Hypertension, Thrombophilia and Oxidative Stress in Mestizo and Amerindian Populations of México

    PubMed Central

    Juárez-Velázquez, Rocio; Canto, Patricia; Canto-Cetina, Thelma; Rangel-Villalobos, Hector; Rosas-Vargas, Haydee; Rodríguez, Maricela; Canizales-Quinteros, Samuel; Velázquez Wong, Ana Claudia; Ordoñez-Razo, Rosa María; Vilchis-Dorantes, Guadalupe; Coral-Vázquez, Ramón Mauricio

    2010-01-01

    Several polymorphisms related to hypertension, thrombophilia, and oxidative stress has been associated with the development of cardiovascular disease. We analyzed the frequency of M235T angiotensinogen (AGT), A222V 5,10 methylenete-trahydrofolate reductase (MTHFR), L33P glycoprotein IIIa (GPIIIa), and I105V glutathione S-transferase P1 (GSTP1) polymorphisms in 285 individuals belonging to Mexican-Mestizo and five Amerindian population from México, by real time PCR allelic discrimination. Allele and genotype frequencies were compared using χ2 tests. All populations followed the Hardy Weinberg equilibrium for assay markers with the exception of the Triki, whose were in Hardy Weinberg dysequilibrium for the glutathione S-transferase P1 polymorphism. Interestingly, according to all the analyzed single nucleotide polymorphisms (SNPs), the Triki population was the most differentiated and homogeneous group of the six populations analyzed. A comparison of our data with those previously published for some Caucasian, Asian and Black populations showed quite significant differences. These differences were remarkable with all the Mexican populations having a lower frequency of the 105V allele of the glutathione S-transferase P1 and reduced occurrence of the 222A allele of the 5,10 methylenetetrahydrofolate reductase. Our results show the genetic diversity among different Mexican populations and with other racial groups. PMID:20592457

  6. Analysis of polymorphisms in genes (AGT, MTHFR, GPIIIa, and GSTP1) associated with hypertension, thrombophilia and oxidative stress in Mestizo and Amerindian populations of México.

    PubMed

    Juárez-Velázquez, Rocio; Canto, Patricia; Canto-Cetina, Thelma; Rangel-Villalobos, Hector; Rosas-Vargas, Haydee; Rodríguez, Maricela; Canizales-Quinteros, Samuel; Velázquez Wong, Ana Claudia; Ordoñez-Razo, Rosa María; Vilchis-Dorantes, Guadalupe; Coral-Vázquez, Ramón Mauricio

    2010-01-01

    Several polymorphisms related to hypertension, thrombophilia, and oxidative stress has been associated with the development of cardiovascular disease. We analyzed the frequency of M235T angiotensinogen (AGT), A222V 5,10 methylenete-trahydrofolate reductase (MTHFR), L33P glycoprotein IIIa (GPIIIa), and I105V glutathione S-transferase P1 (GSTP1)} polymorphisms in 285 individuals belonging to Mexican-Mestizo and five Amerindian population from México, by real time PCR allelic discrimination. Allele and genotype frequencies were compared using chi square tests. All populations followed the Hardy Weinberg equilibrium for assay markers with the exception of the Triki, whose were in Hardy Weinberg dysequilibrium for the glutathione S-transferase P1 polymorphism. Interestingly, according to all the analyzed single nucleotide polymorphisms (SNPs), the Triki population was the most differentiated and homogeneous group of the six populations analyzed. A comparison of our data with those previously published for some Caucasian, Asian and Black populations showed quite significant differences. These differences were remarkable with all the Mexican populations having a lower frequency of the 105V allele of the glutathione S-transferase P1 and reduced occurrence of the 222A allele of the 5,10 methylenetetrahydrofolate reductase. Our results show the genetic diversity among different Mexican populations and with other racial groups.

  7. Real-Time PCR for Dihydrofolate Reductase Gene Single-Nucleotide Polymorphisms in Plasmodium vivax Isolates

    PubMed Central

    Brega, Sara; de Monbrison, Frédérique; Severini, Carlo; Udomsangpetch, Rachanee; Sutanto, Inge; Ruckert, Paul; Peyron, François; Picot, Stéphane

    2004-01-01

    Mutations in the dhfr gene of Plasmodium vivax (pvdhfr) are associated with resistance to the antifolate antimalarial drugs. Polymorphisms in the pvdhfr gene were assessed by hybridization probe technology on the LightCycler instrument with 134 P. vivax-infected blood samples from Turkey (n = 24), Azerbaijan (n = 39), Thailand (n = 16), Indonesia (n = 53), and travelers (n = 19). Double mutations (S58R and S117N) or quadruple mutations (F57L/I, S58R, T61M, and S117N) in the pvdhfr genes were found in all Thai samples (100%). pvdhfr mutant-type alleles were significantly more common in samples from travelers (42%) than in those from patients from Indonesia (5%). Surprisingly, the pvdhfr single-mutation allele (S117N) was identified at a high frequency in parasites from Turkey and Azerbaijan (71 and 36%, respectively), where sulfadoxine-pyrimethamine is not recommended for the treatment of P. vivax malaria by the World Health Organization and the Malaria National Programs. PMID:15215112

  8. [Gene polymorphisms in the dihydrofolate reductase ( dhfr ) and dihydropteroate synthase ( dhps ) genes and structural modelling of the dhps gene in Colombian isolates of Toxoplasma gondii].

    PubMed

    Cortés, Liliana Jazmín; Duque, Sofía; López, Miryam Consuelo; Moncada, Diego; Molina, Diego; Gómez-Marín, Jorge Enrique; Gunturiz, María Luz

    2014-01-01

    There are no reports describing polymorphisms in target genes of anti- Toxoplasma drugs in South American isolates. This study sought to perform cloning and sequencing of the dihydrofolate reductase ( dhfr ) and dihydropteroate-synthase ( dhps ) genes of the reference Rh strain and two Colombian isolates of Toxoplasma gondii . Two isolates were obtained from the cerebrospinal fluid of HIV-infected patients with cerebral toxoplasmosis. A DNA extraction technique and PCR assay for the dhfr and dhps genes were standardized, and the products of amplification were cloned into Escherichia coli and sequenced. One polymorphism (A « G) was found at position 235 of exon 2 in the dhps gene. In addition, two polymorphisms (G « C) at positions 259 and 260 and one polymorphism (T « G) at position 371 within exon 4 of the dhps gene were detected. In this last exon, a bioinformatic analysis revealed a non-synonymous polymorphism in the coding region that could lead to the substitution of Glu (CAA or CAG) for His (encoded by codons AAU or AAC). A structural model of the T. gondii DHPS protein was calculated, and the results revealed modifications in secondary structure due to mutations. The methods described in this study can be used as a tool to search for polymorphisms in samples from patients with different clinical manifestations of toxoplasmosis and to examine their relationship with the therapeutic response.

  9. The use of B vitamins for cutaneous ulcerations mimicking pyoderma gangrenosum in patients with MTHFR polymorphism.

    PubMed

    New, Douglas; Eaton, Philip; Knable, Al; Callen, Jeffrey P

    2011-04-01

    Methylenetetrahydrofolate reductase (MTHFR) polymorphisms are associated with thrombophilia and vasculopathy that may result in cutaneous ulceration. Pyoderma gangrenosum (PG) is a clinical diagnosis that may be made following exclusion of alternate causes of ulceration, including vascular inflammatory or occlusive disease, infection, and malignant neoplasm. We describe 2 patients with MTHFR polymorphisms discovered during hypercoagulable evaluation for cutaneous ulcerations on the lower extremities. Both patients showed a rapid improvement following treatment with oral vitamin supplementation and local wound care. One patient developed several subsequent ulcers when he decided to discontinue his therapy, and following reinitiation of therapy, the new ulcerations healed. The treatment was tolerated well without any adverse effects. MTHFR polymorphisms should be part of a comprehensive laboratory evaluation during hypercoagulable workup. Vitamin supplementation with folic acid (B(9)), pyridoxine hydrochloride (B(6)), and cyanocobalamin (B(12)) may result in healing of cutaneous ulcerations in some patients with MTHFR mutations.

  10. Association of MTHFR, MTR, and MTRR polymorphisms with Parkinson's disease among ethnic Chinese in Taiwan.

    PubMed

    Fong, Chin-Shih; Shyu, Hann-Yeh; Shieh, Jia-Ching; Fu, Yi-Ping; Chin, Ting-Yu; Wang, Hsiao-Wei; Cheng, Chun-Wen

    2011-01-30

    Influence of folate/homocysteine conversion is considered to be important in the pathogenesis of Parkinson's disease (PD). However, association of the folate metabolic pathway gene polymorphisms with PD susceptibility remains unclear. To test this possibility in PD, we conducted a hospital-based case-control study constituting 211 patients and 218 age- and sex-matched controls of ethnic Chinese in Taiwan. Genotyping assay was performed to screen for polymorphisms of the methylenetetrahydrofolate reductase (MTHFR C677T), methyltetrahydrofolate-homocysteine methyltransferase (MTR A2756G), and 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR A1049G and C1783T) genes and assess the association between these genotype polymorphisms and PD risk using logistic regression analysis. Of these four non-synonymous polymorphisms, the MTRR 1049GG variant was significantly associated with PD susceptibility (OR=3.17, 95%CI=1.08-9.35). Furthermore, we stratified our patients based on the MTHFR 677TT genotype in different strata, a significant association between the joint effect of polymorphisms and PD risk was observed in those patients whose genotypes were MTRR A1049G/MTR A2756G or MTRR C1783T/MTR A2756G (P<0.05). Our findings provide support for the synergistic effects of polymorphisms in the folate metabolic pathway genes in PD susceptibility; the increased PD risk would be more significant in carriers with the polymorphisms of MTHFR, MTR, and MTRR genes. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Quinone Reductase 2 Is a Catechol Quinone Reductase

    SciTech Connect

    Fu, Yue; Buryanovskyy, Leonid; Zhang, Zhongtao

    2008-09-05

    The functions of quinone reductase 2 have eluded researchers for decades even though a genetic polymorphism is associated with various neurological disorders. Employing enzymatic studies using adrenochrome as a substrate, we show that quinone reductase 2 is specific for the reduction of adrenochrome, whereas quinone reductase 1 shows no activity. We also solved the crystal structure of quinone reductase 2 in complexes with dopamine and adrenochrome, two compounds that are structurally related to catecholamine quinones. Detailed structural analyses delineate the mechanism of quinone reductase 2 specificity toward catechol quinones in comparison with quinone reductase 1; a side-chain rotational difference between quinone reductase 1 and quinone reductase 2 of a single residue, phenylalanine 106, determines the specificity of enzymatic activities. These results infer functional differences between two homologous enzymes and indicate that quinone reductase 2 could play important roles in the regulation of catecholamine oxidation processes that may be involved in the etiology of Parkinson disease.

  12. [Interactions between lifestyle, methylanetetrahydrofolate reductase gene and polymorphisms in thymidylate synthase gene with risk of stomach cancer].

    PubMed

    Gao, Chang-ming; Wu, Jian-zhong; Liu, Yan-ting; Ding, Jian-hua; Li, Su-ping; Su, Ping; Hu, Xu; Kai, Hai-tao; Toshiro, Takezaki; Kazuo, Tajima

    2003-07-01

    To evaluate interactions between lifestyle, methylanetetrahydrofolate reductase gene (MTHFR) and polymorphisms in the 3'-untranslated region (3'-UTR) of the thymidylate synthase gene (TS) with reference to development of stomach cancer (SC). We conducted a case-control study with 107 cases of SC and 200 population-based controls in Huaian city of Jiangsu province, China. TS genotypes were identified by polymerase chain reaction. (1) The frequencies of TS genotypes (+6 bp/+6 bp, +6 bp/-6 bp and -6 bp/-6 bp) among the cases were 5.6%, 47.7% and 46.7% and among the controls were 9.0%, 54.0% and 37.0%, respectively. Individuals identified as -6 bp/-6 bp genotype had a slightly higher risk for SC than those individuals with +6 bp alleles (the crude OR = 1.49, 95% CI: 0.90 - 2.47; adjusted OR = 1.36, 95% CI: 1.00 - 1.78, P = 0.047). (2) Individuals having TS -6 bp/-6 bp genotype and having smoking habit were at a significantly higher risk of developing SC (adjusted OR = 2.79, 95% CI: 1.51 - 5.18) compared with those who had +6 bp alleles with no smoking habit. Individuals having TS -6 bp/-6 bp genotype and habit of frequent alcohol drinking were at an increased risk of developing SC (adjusted OR = 1.76, 95% CI: 1.07 - 2.90) compared with those with +6 bp alleles and low consumption of alcohol. As compared with individuals with +6 bp alleles and who had habit of tea drinking, individuals who had TS -6 bp/-6 bp genotype and but without habit of tea drinking had an increased risk of developing SC (adjusted OR = 2.34, 95% CI: 1.43 - 3.82). (3) Individuals with TS -6 bp/-6 bp genotype and with MTHFR T alleles had an increased risk of developing SC (adjusted OR = 2.67, 95% CI: 1.07 - 6.70) compared with those with +6 bp alleles and with MTHRF C/C genotype. Results in the present study suggested that there was a combined effect between lifestyle, MTHFR C/T or T/T genotype and TS -6 bp/-6 bp genotype in the development of SC.

  13. Combined folate gene MTHFD and TC polymorphisms as maternal risk factors for Down syndrome in China.

    PubMed

    Liao, Y P; Zhang, D; Zhou, W; Meng, F M; Bao, M S; Xiang, P; Liu, C Q

    2014-03-17

    We examined whether polymorphisms in the methylenetetrahydrofolate dehydrogenase (MTHFD) and transcobalamin (TC) genes, which are involved in folate metabolism, affect maternal risk for Down syndrome. We investigated 76 Down syndrome mothers and 115 control mothers from Bengbu, China. Genomic DNA was isolated from the peripheral lymphocytes. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFD G1958A and TC C776G. The frequencies of the polymorphic alleles were 24.3 and 19.1% for MTHFD 1958A, 53.9 and 54.2% for TC 776G, in the case and control groups, respectively. No significant differences were found between two groups in relation to either the allele or the genotype frequency for both polymorphisms. However, when gene-gene interactions between these two polymorphisms together with previous studied C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene were analyzed, the combined MTHFR 677CT/TT and MTHFD 1958AA/GA genotype was found to be significantly associated with the risk of having a Down syndrome child [odds ratio (OR) = 3.11; 95% confidence interval (95%CI) = 1.07-9.02]. In addition, the combined TC 776CG and MTHFR 677TT genotype increased the risk of having a child with Down syndrome 3.64-fold (OR = 3.64; 95%CI = 1.28-10.31). In conclusion, neither MTHFD G1958A nor TC C776G polymorphisms are an independent risk factor for Down syndrome. However, the combined MTHFD/MTHFR, TC/MTHFR genotypes play a role in the risk of bearing a Down syndrome child in the Chinese population.

  14. [Study of correlationship between congenital heart disease and 5, 10-methylenetetra hydrofolate reductase gene's polymorphism or folacin intakes].

    PubMed

    Li, Dong; Jing, Xue-an; Wang, Hua-yi; Ye, Wen-jing; Fan, Hua

    2009-08-01

    To investigate the correlationship between congenital heart disease and 5, 10-methylenetetra hydrofolate reductase (MTHFR)'s C677T or folacin intakes, and to study the interaction of them in the occurring of congenital heart disease. We used case-control study (case = 104, control = 208) method. Cases and controls were chosen by age, sex and other conditions. The MTHFR C677T genotype distribution was analyzed by using polymerase chain reaction restricted fragment length polymorphism (PCR-RFLP), and non-conditional and multi-conditional logistic regression analysis were also used to analyze the correlationship and interaction of the factors. In case group, the number of people in low folacin intake level was 38 (36.54%), which in control group was 21(10.10%). The intake level of folacin during pregnancy was related to congenital heart disease (chi(2) = 31.614, nu = 1, P < 0.0001). The value of OR was 1.417 with 95%CI 1.216 - 1.651, indicating that the low level of folacin intakes was a risk factor to the congenital heart disease. In case group, the number of TT genotype was 46 (44.24%), the number of CT genotype was 42 (40.38%), the number of CC genotype was 16 (15.38%). In control group, the number of TT genotype was 39 (18.75%), the number of CT genotype was 114 (54.81%), the number of CC genotype was 55 (26.44%). A significant genotype distribution difference was identified between case and control group (chi(2) = 23.13, nu = 2, P < 0.0001). Genotype MTHFR 677TT was a risk factor of congenital heart disease and the OR value was 3.437 (95%CI: 2.042 - 5.784). The interaction analysis suggested that the low level of folacin intakes and the MTHFR 677TT genotype had a positive adding effect in the occurring of congenital heart disease. After adjusted some factors such as the ages of parents, fetus age and sex, the effect values of interaction were 13.343 and 15.911 respectively, and the percentages of attributable interaction effects were 0.619 and 0.612. The

  15. MTHFR polymorphisms in childhood acute lymphoblastic leukemia: influence on methotrexate therapy

    PubMed Central

    Umerez, Maitane; Gutierrez-Camino, Ángela; Muñoz-Maldonado, Carmen; Martin-Guerrero, Idoia; Garcia-Orad, Africa

    2017-01-01

    Methotrexate (MTX) is an important component in the therapy used to treat childhood acute lymphoblastic leukemia (ALL). Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme for MTX pharmacokinetics. Two single-nucleotide polymorphisms in MTHFR gene, C677T and A1298C, affecting MTHFR activity, have been widely studied as potential markers of MTX toxicity and/or outcome in pediatric ALL. In this review, we show that the majority of published reports do not find association or present opposite effect. Therefore, MTHFR C677T and A1298C polymorphisms do not seem to be good markers of MTX-related toxicity and/or outcome in pediatric ALL. The efforts should be focused on other genes, such as transporter genes or microRNA-related genes. PMID:28392709

  16. The Dihydrofolate Reductase 19 bp Polymorphism Is Not Associated with Biomarkers of Folate Status in Healthy Young Adults, Irrespective of Folic Acid Intake.

    PubMed

    Ozaki, Mari; Molloy, Anne M; Mills, James L; Fan, Ruzong; Wang, Yifan; Gibney, Eileen R; Shane, Barry; Brody, Lawrence C; Parle-McDermott, Anne

    2015-10-01

    Dihydrofolate reductase (DHFR) is essential for the conversion of folic acid to active folate needed for one-carbon metabolism. Common genetic variation within DHFR is restricted to the noncoding regions, and previous studies have focused on a 19 bp deletion/insertion polymorphism (rs70991108) within intron 1. Reports of an association between this polymorphism and blood folate biomarker concentrations are conflicting. In this study, we evaluated whether the DHFR 19 bp deletion/insertion polymorphism affects circulating folate biomarkers in, to our knowledge, the largest cohort to address this question to date. Healthy young Irish individuals (n = 2507) between 19 and 36 y of age were recruited between February 2003 and February 2004. Folic acid intake from supplements and fortified foods was assessed with the use of a customized food intake questionnaire. Concentrations of serum folate and vitamin B-12, red blood cell (RBC) folate, and plasma total homocysteine (tHcy) were measured. Data were analyzed with the use of linear regression models. Folic acid intake was positively associated with serum (P < 0.0001) and RBC (P = 0.0005) folate concentration and was inversely associated with plasma tHcy (P = 0.001) as expected. The DHFR 19 bp polymorphism was not significantly associated with either serum (P = 0.82) or RBC (P = 0.21) folate, or plasma tHcy (P = 0.20), even in those within the highest quintile of folic acid intake (>326 μg folic acid/d; P = 0.96). A nonsignificant trend toward lower RBC folate by genotype (P = 0.09) was observed in the lowest folic acid intake quintile (0-51 μg/d). In this cohort of healthy young individuals, the DHFR 19 bp deletion allele did not significantly affect circulating folate status, irrespective of folic acid intake. Our data rule out a strong functional effect from this polymorphism on blood folate concentrations. © 2015 American Society for Nutrition.

  17. A variety of gene polymorphisms associated with idiopathic granulomatous mastitis

    PubMed Central

    Destek, Sebahattin; Gul, Vahit Onur; Ahioglu, Serkan

    2016-01-01

    Idiopathic granulomatous mastitis (IGM) is a rare and chronic inflammatory disorder. IGM mimics breast cancer regarding its clinical and radiological features. Etiology of IGM remains unclarified. Our patient was 37-year-old and 14 weeks pregnant. There was pain, redness and swelling in the right breast. The mass suggestive of malignancy was detected in sonography. Serum CA 125 and CA 15-3 levels were high. Genetic analysis was performed for the etiology. methylenetetrahydrofolate reductase (MTHFR) C 677 TT, β-fibrinogen-455 G>A, plasminogen activator inhibitor (PAI)-1 5 G/5 G, angiotensin-converting enzyme (ACE) I/D mutation was found. IGM was diagnosed by cor biopsy. An association was also reported between breast cancer and mutations in MTHFR-C 677 T, PAI-1, ACE genes. Genetic polymorphisms may involve in the development of IGM as it was seen in our case. Further studies should be conducted to better clarify this plausible association. PMID:27619324

  18. Genetic polymorphisms involved in folate metabolism and elevated plasma concentrations of homocysteine: maternal risk factors for Down syndrome in Brazil.

    PubMed

    Biselli, J M; Goloni-Bertollo, E M; Zampieri, B L; Haddad, R; Eberlin, M N; Pavarino-Bertelli, E C

    2008-01-22

    The aim of the present study was to investigate the effect of polymorphisms C677T and A1298C in the methylenetetrahydrofolate reductase (MTHFR) gene, A2756G in methionine synthase reductase (MTR) gene and A80G in reduced folate carrier 1 (RFC1) gene, and plasma homocysteine (Hcy), on the maternal risk for Down syndrome (DS). Seventy-two DS mothers and 194 mothers who had no children with DS were evaluated. The investigation of the MTHFR C677T, MTR A2756G and RFC1 A80G polymorphisms was performed by polymerase chain reaction and enzyme digestion and the MTHFR A1298C polymorphism by allele-specific polymerase chain reaction. Hcy quantification was carried out by liquid chromatography-tandem mass spectrometry. The median number of polymorphic alleles for the four loci tested was greater in DS mothers compared to the control group, and the presence of three or more polymorphic alleles increased the risk for having a child with DS 1.74 times. Elevated maternal risk for DS was also observed when plasma Hcy concentration was higher than 4.99 micromol/L. In conclusion, the presence of three or more polymorphic alleles for MTHFR C677T, MTHFR A1298C, MTR A2756G, and RFC1 A80G, and plasma Hcy concentrations higher than 4.99 micromol/L are maternal risk factors for DS.

  19. Evaluation of AC(n) and C(-106)T polymorphisms of the aldose reductase gene in Brazilian patients with DM1 and susceptibility to diabetic retinopathy

    PubMed Central

    Richeti, Flávio; Noronha, Renata Maria; Waetge, Ricardo Temudo Lessa; Cabral de Vasconcellos, José Paulo; Francisco de Souza, Osías; Kneipp, Bianca; Assis, Nilma; Rocha, Mylene Neves; Calliari, Luís Eduardo Procópio; Longui, Carlos Alberto; Monte, Osmar

    2007-01-01

    Purpose Diabetic retinopathy (DR) is one of the most important microvascular complications in both type 1 and type 2 diabetes. In Brazil, its proliferative form is the second cause of irreversible blindness among adults of working age. Despite the strong association of DR with disease duration and degree of chronic hyperglycemia, genetic predisposition has been recognized as a possible trigger in the development of this complication. Recent studies have demonstrated that the development of DR in patients with type 1 diabetes is associated with the occurrence of polymorphisms at the 5'-end of the aldose reductase gene (ALR2). There are no reports investigating these polymorphisms in type 1 diabetes Brazilian patients. The aim of this study was to investigate the relationship between the AC(n) repeat and C(-106)T polymorphisms of the ALR2 gene with the susceptibility to the development of DR in Brazilian patients with type 1 diabetes. Methods We selected 64 patients who had diabetes for at least 10 years from Santa Casa de São Paulo and State University of Campinas. The study group was divided into the following: Group 1, patients with no evidence of diabetic retinopathy; group 2, patients with nonproliferative diabetic retinopathy (NPDR); and group 3, patients with proliferative diabetic retinopathy (PDR), confirmed by fundoscopy. The AC(n) microsatellite region was evaluated through polymerase chain reaction (PCR) and automated genotyping and the C(-106)T substitution through polymerase chain reaction/restriction fragment length polymorphism (RFLP). Results When each allele of the AC(n) polymorphism was evaluated, the Z allele (24 repeats) was significantly associated with the development of PDR (p=0.014). The C allele of the C(-106)T substitution wasn't associated with the susceptibility to this microvascular complication (p=0.153). When the Z and C allele were concomitantly evaluated regarding their presence or absence a positive correlation was observed for the

  20. Susceptibility to diabetic neuropathy in patients with insulin dependent diabetes mellitus is associated with a polymorphism at the 5' end of the aldose reductase gene

    PubMed Central

    Heesom, A.; Millward, A.; Demaine, A.

    1998-01-01

    OBJECTIVES—There is evidence that the polyol pathway is involved in the pathogenesis of diabetic neuropathy. Aldose reductase (ALR2) is the first and rate limiting enzyme of this pathway and recent studies have suggested that polymorphisms in and around the gene are associated with the development of diabetic microvascular disease. The aim was to examine the role of ALR2 in the susceptibility to diabetic neuropathy in patients with insulin dependent diabetes mellitus (IDDM).
METHODS—One hundred and fifty nine British white patients with IDDM and 102 normal healthy controls were studied using the polymerase chain reaction to test for a highly polymorphic microsatellite marker 2.1 kilobase (kb) upstream of the initiation site of the ALR2 gene.
RESULTS—Seven alleles were detected (Z-6, Z-4, Z-2, Z, Z+2, Z+4, and Z+6). There was a highly significant decrease in the frequency of the Z+2 allele in those patients with overt neuropathy compared with those with no neuropathy after 20 years duration of diabetes (14.1% v 38.2%, χ2 =17.3, p<0.00001). A similar difference was also found between the neuropathy group and those patients who have had diabetes for< five years with no overt neuropathy (14.1% v 30.2%, χ2=9.0, p<0.0025). The neuropathy group also had a significant decrease in the frequency of the Z/Z+2 genotype compared with those patients who have no neuropathy after 20 years duration of diabetes (14.0% v 44.7%, χ2=13.0, p<0.0005).
CONCLUSION—These results suggest that the aldose reductase gene is intimately involved in the pathogenesis of diabetic neuropathy.

 PMID:9489533

  1. Lack of association between the methylenetetrahydropholate reductase gene A1298C polymorphism and neural tube defects in a Turkish study group.

    PubMed

    Yildiz, S H; Ozdemir Erdogan, M; Solak, M; Eser, O; Arıkan Terzi, E S; Eser, B; Kocabaş, V; Aslan, A

    2016-06-03

    The etiology underlying neural tube defects (NTDs) is not fully understood and is believed to involve a complex milieu of genetic and environmental factors. The A1298C polymorphism in the methylenetetrahydropholate reductase gene (MTHFR) has been associated with mild risk for NTDs. In this study, the genotype distribution of the MTHFR gene A1298C polymorphism and the levels of serum homocysteine, vitamin B12, and folate were evaluated in 33 children with NTDs, their mothers, and 46 healthy controls. Genotyping of the A1298C polymorphism was performed by real-time polymerase chain reaction. The A and C allele frequencies in children with NTDs and their mothers were similar to controls (P = 0.160). The 1298AA and 1298CC genotype frequencies (P = 0.551 and 0.062, respectively) in children with NTDs and their mothers did not differ from controls. On the other hand, the 1298AC genotype frequencies in children with NTDs and their mothers were significantly different from controls (P = 0.025). The genotype frequency of 1298AC was lower in children with NTDs than in controls. There was no significant association between clinical distribution of NTDs and 1298AA/AC/CC genotypes (P > 0.05). Serum vitamin B12 levels were higher in children with NTDs than their mothers and controls (P = 0.001). There were no differences among serum homocysteine and folate levels in all groups (P = 0.494 and 0.141, respectively). Both genetic and nutritional factors are important in the etiology of NTDs. Thus, the A1298C polymorphism cannot be regarded as a major risk factor for NTDs.

  2. A 19-base pair deletion polymorphism in dihydrofolate reductase is associated with increased unmetabolized folic acid in plasma and decreased red blood cell folate.

    PubMed

    Kalmbach, Renee D; Choumenkovitch, Silvina F; Troen, Aron P; Jacques, Paul F; D'Agostino, Ralph; Selhub, Jacob

    2008-12-01

    Dihydrofolate reductase (DHFR) catalyzes the reduction of folic acid to tetrahydrofolate (THF). A 19-bp noncoding deletion allele maps to intron 1, beginning 60 bases from the splice donor site, and has been implicated in neural tube defects and cancer, presumably by influencing folate metabolism. The functional impact of this polymorphism has not yet been demonstrated. The objective of this research was to determine the effects of the DHFR mutation with respect to folate status and assess influence of folic acid intake on these relations. The relationship between DHFR genotype and plasma concentrations of circulating folic acid, total folate, total homocysteine, and concentrations of RBC folate was determined in 1215 subjects from the Framingham Offspring Study. There was a significant interaction between DHFR genotype and folic acid intake with respect to the prevalence of high circulating unmetabolized folic acid (defined as >85th percentile). Folic acid intake of >or=500 microg/d increased the prevalence of high circulating unmetabolized folic acid in subjects with the deletion (del/del genotype (47.0%) compared with the wild type (WT)/del (21.4%) and wild type (WT)/WT genotypes (24.4%) (P for interaction = 0.03). Interaction between the DHFR polymorphism and folic acid intake was also seen with respect to RBC folate (P for interaction = 0.01). When folic acid intake was <250 microg/d, the del/del genotype was associated with significantly lower RBC folate (732.3 nmol/L) compared with the WT/WT genotype (844.4 nmol/L). Our results suggest the del/del polymorphism in DHFR is a functional polymorphism, because it limits assimilation of folic acid into cellular folate stores at high and low folic acid intakes.

  3. Association of methionine synthase rs1801394 and methionine synthase reductase rs1805087 polymorphisms with meningioma in adults: A meta-analysis

    PubMed Central

    ZENG, XIAN-TAO; LU, JUN-TI; TANG, XIANG-JUN; WENG, HONG; LUO, JIE

    2014-01-01

    Several epidemiological studies suggested that methionine synthase (MTRR) rs1801394 and methionine synthase reductase (MTR) rs1805087 polymorphisms may be involved in the risk of meningioma in adults; however, the results from different case-control studies have been inconsistent. Therefore, we performed a meta-analysis to investigate the association of MTRR and MTR polymorphisms with meningioma. PubMed, Web of Knowledge, China National Knowledge Infrastructure and Wanfang databases were searched up to October 30, 2013 and 3 publications, involving 7 case-control studies, were finally included. Following data extraction, a meta-analysis was conducted using Stata 12.0 software. The pooled results based on the fixed effects model demonstrated that the MTRR rs1801394 polymorphism was associated with an increased risk of meningioma [odds ratio (OR)=1.18, 95% confidence interval (CI): 1.05–1.32 for G vs. A; OR=1.41, 95% CI: 1.12–1.77 for GG vs. AA; OR=1.08, 95% CI: 0.94–1.33 for AG vs. AA; OR=1.19, 95% CI: 1.01–1.40 for (AG+GG) vs. AA; and OR=1.32, 95% CI: 1.07–1.63 for GG vs. (AG+AA)]; however, an association between the MTR rs1805087 polymorphism and the risk of meningioma was not identified [OR=0.99, 95% CI: 0.88–1.12 for G vs. A; OR=1.09, 95% CI: 0.80–1.48 for GG vs. AA; OR=0.95, 95% CI: 0.82–1.11 for AG vs. AA; OR=0.97, 95% CI: 0.84–1.13 for (AG+GG) vs. AA; and OR=1.09, 95% CI: 0.80–1.48 for GG vs. (AG+AA)]. Therefore, the currently available evidence suggests that the MTRR rs1801394 polymorphism may increase the risk of meningioma, whereas the MTRR rs1801394 polymorphism is not associated with meningioma. PMID:24748989

  4. One-carbon metabolism-related gene polymorphisms and risk of head and neck squamous cell carcinoma: case-control study.

    PubMed

    Suzuki, Takeshi; Matsuo, Keitaro; Hasegawa, Yasuhisa; Hiraki, Akio; Wakai, Kenji; Hirose, Kaoru; Saito, Toshiko; Sato, Shigeki; Ueda, Ryuzo; Tajima, Kazuo

    2007-09-01

    Low consumption of vegetables and fruits, which leads to insufficient folate intake, is associated with increased risk of several types of cancer, including head and neck squamous cell carcinoma (HNSCC). Functional polymorphisms in genes encoding one-carbon metabolism enzymes, such as methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MTR A2756G), methionine synthase reductase (MTRR A66G) and thymidylate synthase (TS), influence folate metabolism and thus might impact on HNSCC risk. We conducted a case-control study with 237 HNSCC cases newly and histologically diagnosed and 711 age- and sex-matched non-cancer controls to clarify associations with these five polymorphisms. Gene-environment interactions between polymorphisms and smoking and drinking habit and folate consumption were also evaluated by logistic regression analysis. Dietary folate intake was inversely associated with HNSCC risk. None of the polymorphisms showed any significant impact on HNSCC risk by genotype alone, but we found interactions between drinking habit and MTHFR C667T (P = 0.04), MTR A2756G (P = 0.04) and MTRR A66G (P = 0.03) polymorphisms. The results suggest that there may be interactions between one-carbon metabolism-related polymorphisms and alcohol drinking for HNSCC risk.

  5. Genetic polymorphisms in one-carbon metabolism: associations with CpG island methylator phenotype (CIMP) in colon cancer and the modifying effects of diet

    PubMed Central

    Curtin, Karen; Slattery, Martha L.; Ulrich, Cornelia M.; Bigler, Jeannette; Levin, Theodore R.; Wolff, Roger K.; Albertsen, Hans; Potter, John D.; Samowitz, Wade S.

    2008-01-01

    This study investigated associations between CpG island methylator phenotype (CIMP) colon cancer and genetic polymorphisms relevant to one-carbon metabolism and thus, potentially the provision of methyl groups and risk of colon cancer. Data from a large, population-based case–control study (916 incident colon cancer cases and 1972 matched controls) were used. Candidate polymorphisms in methylenetetrahydrofolate reductase (MTHFR), thymidylate synthase (TS), transcobalamin II (TCNII), methionine synthase (MTR), reduced folate carrier (RFC), methylene-tetrahydrofolate dehydrogenase 1 (MTHFD1), dihydrofolate reductase (DHFR) and alcohol dehydrogenase 3 (ADH3) were evaluated. CIMP− or CIMP+ phenotype was based on five CpG island markers: MINT1, MINT2, MINT31, p16 and MLH1. The influence of specific dietary factors (folate, methionine, vitamin B12 and alcohol) on these associations was also analyzed. We hypothesized that polymorphisms involved in the provision of methyl groups would be associated with CIMP+ tumors (two or more of five markers methylated), potentially modified by diet. Few associations specific to CIMP+ tumors were observed overall, which does not support the hypothesis that the provision of methyl groups is important in defining a methylator phenotype. However, our data suggest that genetic polymorphisms in MTHFR 1298A > C, interacting with diet, may be involved in the development of highly CpG-methylated colon cancers. AC and CC genotypes in conjunction with a high-risk dietary pattern (low folate and methionine intake and high alcohol use) were associated with CIMP+ (OR = 2.1, 95% CI = 1.3–3.4 versus AA/high risk; P-interaction = 0.03). These results provide only limited support for a role of polymorphisms in one-carbon metabolism in the etiology of CIMP colon cancer. PMID:17449906

  6. MTRR and MTHFR polymorphism: link to Down syndrome?

    PubMed

    O'Leary, Valerie B; Parle-McDermott, Anne; Molloy, Anne M; Kirke, Peadar N; Johnson, Zachary; Conley, Mary; Scott, John M; Mills, James L

    2002-01-15

    Polymorphisms in genes encoding the folate metabolizing enzymes methylenetetrahydrofolate reductase (MTHFR C677T) and methionine synthase reductase (MTRR A66G) have been linked to the etiology of Down syndrome. We examined the prevalence of these variant genotypes in mothers who had given birth to a child with Down syndrome (n = 48) and in control mothers (n = 192), and investigated the biochemical factors influenced by the presence of MTRR A66G and MTHFR C677T. The frequency of the MTRR variant genotypes (AG, GG) was significantly higher in mothers of children with Down syndrome compared to controls (P = 0.0028). MTHFR C677T genotype frequencies were not significantly altered in mothers of children with Down syndrome (P = 0.74). However, mothers who had a MTHFR CT or TT genotype and a MTRR GG genotype had a 2.98-fold increased risk of having a child with Down syndrome (P = 0.02). The MTRR polymorphism did not increase plasma homocysteine. Higher homocysteine was found with the presence of the MTHFR T allele. In conclusion, MTRR A66G is significantly more common in mothers of children with Down syndrome but does not appear to increase the risk for Down syndrome by changing homocysteine metabolism. Women who have both the MTRR and MTHFR variant genotypes are also at increased risk of producing offspring with Down syndrome.

  7. Fetal anticonvulsant syndromes and polymorphisms in MTHFR, MTR, and MTRR.

    PubMed

    Dean, John; Robertson, Zoe; Reid, V; Wang, Q Diana; Hailey, Hazel; Moore, Sue; Rasalam, A Dee; Turnpenny, Peter; Lloyd, David; Cardy, Amanda; Shaw, Duncan; Little, Julian

    2007-10-01

    The malformations found in fetal anticonvulsant syndromes (FACS) are associated with folic acid deficiency and methylene-tetrahydrofolate reductase (MTHFR) polymorphisms in the general population. To investigate a possible association between FACS and MTHFR genotype, we recruited 200 mothers who had taken anti-epileptic drugs in pregnancy, and delivered at Aberdeen Maternity Hospital over a 26-year period. Clinical findings in the mothers and their 337 children were documented. A clinical algorithm was devised to diagnose FACS objectively. Case-parent triads were genotyped for polymorphisms in MTHFR, serine hydroxymethyl transferase (SHMT1), methionine synthase (MTR), and methionine synthase reductase (MTRR), and analyzed by log-linear regression. No effect of the child's genotype on congenital malformation, neurodevelopmental disorder or FACS was detected using this method. The risk of having a child with congenital malformation or FACS was three to four times higher for mothers who were MTHFR 677TT homozygotes compared with MTHFR 677CC homozygotes. MTR 2756A > G and MTRR 66A > G genotype frequencies in children with FACS and neurodevelopmental disorder were different from those in healthy blood donor controls. 2007 Wiley-Liss, Inc

  8. Combined effect of polymorphisms in type III 5-α reductase and androgen receptor gene with the risk of benign prostatic hyperplasia in Korea

    PubMed Central

    Lee, Chung Lyul; Lee, Jaegeun; Na, Yong Gil; Song, Ki Hak

    2016-01-01

    We evaluated whether type III 5-alpha reductase (SRD5A3; steroid reductase 5-alpha 3) polymorphism was associated with susceptibility of benign prostate hyperplasia (BPH) and the combined effects in BPH risk between the type of short tandem repeat (STR) in SRD5A3 and the length of trinucleotide (CAG) repeats in androgen receptor (AR) gene. We compared the length of AC repeats in STR region of SRD5A3 gene and a CAG repeat in AR in 188 BPH patients who underwent transurethral resection of prostate (TURP) and 98 controls by polymerase chain reaction-based methods. We defined short type was less than 21 copies of AC repeats. The odds ratio for BPH between the men with at least one of short type and with both large types of STR in SRD5A3 gene was 3.10 (95% confidence interval [CI], 1.87–5.16; P=0.000). And BPH was 2.35 times more likely to occur in with less than 23 copies of CAG repeats than men equal or greater than 23 copies in AR gene (95% CI, 1.18–2.36; P=0.016). The men with the large type of STR and ≥23 copies of CAG repeats have 5.3 times BPH risk compared to the reference group with the at least one of the short type of STR and <23 copies (P<0.000). In conclusion, these results suggest that shorter AC repeats of SRD5A3 gene and shorter CAG repeats of AR gene were associated with an increased risk for BPH. However, the interaction between above two factors was not affected in risk of BPH. PMID:27807533

  9. Polymorphisms in the CBS gene and homocysteine, folate and vitamin B12 levels: association with polymorphisms in the MTHFR and MTRR genes in Brazilian children.

    PubMed

    Aléssio, Ana C M; Siqueira, Lúcia H; Bydlowski, Sérgio P; Höehr, Nelci F; Annichino-Bizzacchi, Joyce M

    2008-10-15

    Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR) and cystathionine beta-synthase (CBS) genes, involved in the intracellular metabolism of homocysteine (Hcy), can result in hyperhomocysteinemia. The objective of this study was to evaluate prevalence estimates of CBS T833C, G919A and the insertion of 68-bp (844ins68) polymorphisms and their correlation with Hcy, folate and B(12) in 220 children previously genotyped for MTHFR C677T, A1298C, and MTRR A66G. The prevalence of heterozygote children for 844ins68 was 19.5%. The T833C CBS mutation was identified in association with 844ins68 in all the carriers of the insertion. Genotyping for CBS G919A mutation showed that all the children presented the GG genotype. Analysis of Hcy, B(12) and folate, according to the combination of the different genotypes of the C677T and A1298C MTHFR, A66G MTRR, and 844ins68 CBS showed that the 677TT/1298AA/68WW genotype is associated with an increase in Hcy, when compared to the 677CC/1298AC/68WW (P = 0.033) and the 677CT/1298AA/68WW genotypes (P = 0.034). Since B(12) and folate were not different between these groups, a genetic interaction between diverse polymorphisms probably influences Hcy. Our results emphasize the role of genetic interactions in Hcy levels. 2008 Wiley-Liss, Inc.

  10. A single-nucleotide polymorphism in the methylene tetrahydrofolate reductase (MTHFR) gene is associated with risk of radiation pneumonitis in lung cancer patients treated with thoracic radiation therapy.

    PubMed

    Mak, Raymond H; Alexander, Brian M; Asomaning, Kofi; Heist, Rebecca S; Liu, Chen-yu; Su, Li; Zhai, Rihong; Ancukiewicz, Marek; Napolitano, Brian; Niemierko, Andrzej; Willers, Henning; Choi, Noah C; Christiani, David C

    2012-07-15

    This study examined the association between functional single-nucleotide polymorphisms in candidate genes from oxidative stress pathways and risk of radiation pneumonitis (RP) in patients treated with thoracic radiation therapy for locally advanced lung cancer. A review was conducted of 136 patients treated with radiation therapy for lung cancer between 2001 and 2007, and who had prior genotyping of functional single-nucleotide polymorphisms in oxidative stress genes including superoxide dismutase 2 (SOD2; rs4880) and methylene tetrahydrofolate reductase (MTHFR; rs1801131, rs1801133). RP events were retrospectively scored using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0. Cox proportional hazard regression was performed to identify clinical variables and genotypes associated with risk of RP of grades ≥2 and ≥3 on univariate and multivariate analysis, respectively. P values were corrected for multiple hypothesis esting. With a median follow-up of 21.4 months, the incidence of grade ≥2 RP was 29% and grade ≥3 RP was 14%. On multivariate analysis, after adjusting for clinical factors such as concurrent chemotherapy and consolidation docetaxel, and lung dosimetric parameters such as volume receiving greater than 20 Gy and mean lung dose, MTHFR genotype (rs1801131; AA versus AC/CC) was significantly associated with risk of grade ≥2 RP (hazard ratio: 0.37; 95% confidence interval: 0.18-0.76; P = .006, corrected P = .018) and grade ≥3 RP (hazard ratio: 0.21; 95% confidence interval: 0.06-0.70; P = .01; corrected P = .03). SOD2 genotype was not associated with RP. This study showed an association between MTHFR genotype and risk of clinically significant RP. Further study of MTHFR-related pathways may provide insight into the mechanisms behind RP. Copyright © 2011 American Cancer Society.

  11. The association of 5-alpha reductase type 2 (SRD5A2) gene polymorphisms with prostate cancer in a Korean population.

    PubMed

    Choi, Se Young; Kim, Hae Jong; Cheong, Hyun Sub; Myung, Soon Chul

    2015-01-01

    Steroid 5-alpha reductase type 2 (SRD5A2) modifies testosterone to dihydrotestosterone (DHT) in the prostate. Single-nucleotide polymorphisms (SNPs) of the SRD5A2 gene might affect DHT. We sought to understand the relationship of SRD5A2 SNPs to prostate cancer in the Korean population. Twenty-six common SNPs in the SRD5A2 gene were assessed in 272 prostate cancer cases and 173 controls. Single-locus analyses were conducted by using conditional logistic regression. Additionally, we performed a haplotype analysis for the SRD5A2 SNPs tested. Among the 20 SNPs and 4 haplotypes, there were no statistically significant results in the prostate cancer patients and the controls. In the logistic analysis of SRD5A2 polymorphisms with prostate-specific antigen (PSA) criteria, two SNPs (rs508562, rs11675297) and haplotype 1 displayed significant results (odds ratio [OR], 1.76; p=0.05; OR, 1.88-2.02; p=0.01-0.04; OR, 0.59; p=0.02, respectively). rs508562, rs11675297, rs2208532, and haplotype 1 (OR, 1.49; p=0.05; OR, 2.02; p=0.05; OR, 2.01; p=0.04; OR, 0.56-0.64, p=0.03-0.04, respectively) had significant associations with Gleason score. rs508562, rs11675297, and haplotype 1 (OR, 1.41-2.34; p=0.004-0.05; OR, 1.74-1.82; p=0.03-0.05; OR, 0.42-0.67; p=0.0005-0.03, respectively) were significantly associated with clinical stage. We conclude that there was no significant association between SRD5A2 SNPs and the risk of prostate cancer in the Korean population. However, we found that some SNPs and 1 haplotype influenced PSA level, Gleason score, and clinical stage.

  12. Association between C677T polymorphism of methylene tetrahydrofolate reductase and congenital heart disease: meta-analysis of 7697 cases and 13,125 controls.

    PubMed

    Mamasoula, Chrysovalanto; Prentice, R Reid; Pierscionek, Tomasz; Pangilinan, Faith; Mills, James L; Druschel, Charlotte; Pass, Kenneth; Russell, Mark W; Hall, Darroch; Töpf, Ana; Brown, Danielle L; Zelenika, Diana; Bentham, Jamie; Cosgrove, Catherine; Bhattacharya, Shoumo; Riveron, Javier Granados; Setchfield, Kerry; Brook, J David; Bu'Lock, Frances A; Thornborough, Chris; Rahman, Thahira J; Doza, Julian Palomino; Tan, Huay L; O'Sullivan, John; Stuart, A Graham; Blue, Gillian; Winlaw, David; Postma, Alex V; Mulder, Barbara J M; Zwinderman, Aelko H; van Engelen, Klaartje; Moorman, Antoon F M; Rauch, Anita; Gewillig, Marc; Breckpot, Jeroen; Devriendt, Koen; Lathrop, G Mark; Farrall, Martin; Goodship, Judith A; Cordell, Heather J; Brody, Lawrence C; Keavney, Bernard D

    2013-08-01

    Association between the C677T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene and congenital heart disease (CHD) is contentious. We compared genotypes between CHD cases and controls and between mothers of CHD cases and controls. We placed our results in context by conducting meta-analyses of previously published studies. Among 5814 cases with primary genotype data and 10 056 controls, there was no evidence of association between MTHFR C677T genotype and CHD risk (odds ratio [OR], 0.96 [95% confidence interval, 0.87-1.07]). A random-effects meta-analysis of all studies (involving 7697 cases and 13 125 controls) suggested the presence of association (OR, 1.25 [95% confidence interval, 1.03-1.51]; P=0.022) but with substantial heterogeneity among contributing studies (I(2)=64.4%) and evidence of publication bias. Meta-analysis of large studies only (defined by a variance of the log OR <0.05), which together contributed 83% of all cases, yielded no evidence of association (OR, 0.97 [95% confidence interval, 0.91-1.03]) without significant heterogeneity (I(2)=0). Moreover, meta-analysis of 1781 mothers of CHD cases (829 of whom were genotyped in this study) and 19 861 controls revealed no evidence of association between maternal C677T genotype and risk of CHD in offspring (OR, 1.13 [95% confidence interval, 0.87-1.47]). There was no significant association between MTHFR genotype and CHD risk in large studies from regions with different levels of dietary folate. The MTHFR C677T polymorphism, which directly influences plasma folate levels, is not associated with CHD risk. Publication biases appear to substantially contaminate the literature with regard to this genetic association.

  13. Association between C677T Polymorphism of Methylene Tetrahydrofolate Reductase and Congenital Heart Disease: Meta-Analysis of 7,697 Cases and 13,125 Controls

    PubMed Central

    Mamasoula, Chrysovalanto; Prentice, R. Reid; Pierscionek, Tomasz; Pangilinan, Faith; Mills, James L.; Druschel, Charlotte; Pass, Kenneth; Russell, Mark W.; Hall, Darroch; Töpf, Ana; Brown, Danielle L.; Zelenika, Diana; Bentham, Jamie; Cosgrove, Catherine; Bhattacharya, Shoumo; Riveron, Javier Granados; Setchfield, Kerry; Brook, J. David; Bu'Lock, Frances A.; Thornborough, Chris; Rahman, Thahira J.; Doza, Julian Palomino; Tan, Huay L.; O'Sullivan, John; Stuart, A. Graham; Blue, Gillian; Winlaw, David; Postma, Alex V.; Mulder, Barbara J.M.; Zwinderman, Aelko H.; van Engelen, Klaartje; Moorman, Antoon F.M.; Rauch, Anita; Gewillig, Marc; Breckpot, Jeroen; Devriendt, Koen; Lathrop, G. Mark; Farrall, Martin; Goodship, Judith A.; Cordell, Heather J.; Brody, Lawrence C.; Keavney, Bernard D.

    2013-01-01

    Background Association between the C677T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene and congenital heart disease (CHD) is contentious. Methods and Results We compared genotypes between CHD cases and controls, and between mothers of CHD cases and controls. We placed our results in context by conducting metaanalyses of previously published studies. Among 5,814 cases with primary genotype data and 10,056 controls, there was no evidence of association between MTHFR C677T genotype and CHD risk (OR 0.96 [95% CI 0.87-1.07]). A random-effects meta-analysis of all studies (involving 7,697 cases and 13,125 controls) suggested the presence of association (OR 1.25 [95% CI 1.03-1.51]; p=0.022), but with substantial heterogeneity among contributing studies (I2=64.4%), and evidence of publication bias. Meta-analysis of large studies only (defined by a variance of the log OR less than 0.05), which together contributed 83% of all cases, yielded no evidence of association (OR 0.97 [95% CI 0.91-1.03]), without significant heterogeneity (I2=0). Moreover, meta-analysis of 1,781 mothers of CHD cases (829 of whom were genotyped in this study) and 19,861 controls revealed no evidence of association between maternal C677T genotype and risk of CHD in offspring (OR 1.13 [95% CI 0.87-1.47]). There was no significant association between MTHFR genotype and CHD risk in large studies from regions with different levels of dietary folate. Conclusions The MTHFR C677T polymorphism, which directly influences plasma folate levels, is not associated with CHD risk. Publication biases appear to substantially contaminate the literature with regard to this genetic association. PMID:23876493

  14. "Polymorphisms in folate metabolism genes as maternal risk factor for neural tube defects: an updated meta-analysis".

    PubMed

    Yadav, Upendra; Kumar, Pradeep; Yadav, Sushil Kumar; Mishra, Om Prakash; Rai, Vandana

    2015-02-01

    Epidemiological studies have evaluated the association between maternal methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G polymorphisms and risk of neural tube defects (NTDs) in offspring. However, the results from the published studies on the association between these three polymorphisms and NTD risk are conflicting. To derive a clearer picture of association between these three maternal polymorphisms and risk of NTD, we performed meta-analysis. A comprehensive search was conducted to identify all case-control studies of maternal MTHFR and MTRR polymorphisms and NTD risk. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. Overall, we found that maternal MTHFR C677T polymorphism (OR(TvsC) =1.20; 95% CI = 1.13-1.28) and MTRR A66G polymorphism (OR(GvsA) = 1.21; 95% CI = 0.98-1.49) were risk factors for producing offspring with NTD but maternal MTHFR A1298C polymorphism (OR(CvsA) = 0.91; 95% CI = 0.78-1.07) was not associated with NTD risk. However, in stratified analysis by geographical regions, we found that the maternal C677T polymorphism was significantly associated with the risk of NTD in Asian (OR(TvsC) = 1.43; 95% CI: 1.05-1.94), European (OR(TvsC) = 1.13; 95% CI: 1.04-1.24) and American (OR(TvsC) = 1.26; 95% CI: 1.13-1.41) populations. In conclusion, present meta-analysis supports that the maternal MTHFR C677T and MTRR A66G are polymorphisms contributory to risk for NTD.

  15. Are MTHFR C677T and MTRR A66G Polymorphisms Associated with Overweight/Obesity Risk? From a Case-Control to a Meta-Analysis of 30,327 Subjects.

    PubMed

    Fan, Shu-Jun; Yang, Bo-Yi; Zhi, Xue-Yuan; He, Miao; Wang, Da; Wang, Yan-Xun; Wang, Yi-Nuo; Wei, Jian; Zheng, Quan-Mei; Sun, Gui-Fan

    2015-05-26

    Several studies have examined the associations of methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase reductase (MTRR) A66G polymorphisms with being overweight/obesity. However, the results are still controversial. We therefore conducted a case-control study (517 cases and 741 controls) in a Chinese Han population and then performed a meta-analysis by combining previous studies (5431 cases and 24,896 controls). In our case-control study, the MTHFR C677T polymorphism was not significantly associated with being overweight/obesity when examining homozygous codominant, heterozygous codominant, dominant, recessive and allelic genetic models. The following meta-analysis confirmed our case-control results. Heterogeneity was minimal in the overall analysis, and sensitivity analyses and publication bias tests indicated that the meta-analytic results were reliable. Similarly, both the case-control study and meta-analysis found no significant association between the MTRR A66G polymorphism and being overweight/obesity. However, sensitivity analyses showed that the associations between the MTRR A66G polymorphism and being overweight/obesity became significant in the dominant, heterozygous codominant and allelic models after excluding our case-control study. The results from our case-control study and meta-analysis suggest that both of the two polymorphisms are not associated with being overweight/obesity. Further large-scale population-based studies, especially for the MTRR A66G polymorphism, are still needed to confirm or refute our findings.

  16. Are MTHFR C677T and MTRR A66G Polymorphisms Associated with Overweight/Obesity Risk? From a Case-Control to a Meta-Analysis of 30,327 Subjects

    PubMed Central

    Fan, Shu-Jun; Yang, Bo-Yi; Zhi, Xue-Yuan; He, Miao; Wang, Da; Wang, Yan-Xun; Wang, Yi-Nuo; Wei, Jian; Zheng, Quan-Mei; Sun, Gui-Fan

    2015-01-01

    Several studies have examined the associations of methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase reductase (MTRR) A66G polymorphisms with being overweight/obesity. However, the results are still controversial. We therefore conducted a case-control study (517 cases and 741 controls) in a Chinese Han population and then performed a meta-analysis by combining previous studies (5431 cases and 24,896 controls). In our case-control study, the MTHFR C677T polymorphism was not significantly associated with being overweight/obesity when examining homozygous codominant, heterozygous codominant, dominant, recessive and allelic genetic models. The following meta-analysis confirmed our case-control results. Heterogeneity was minimal in the overall analysis, and sensitivity analyses and publication bias tests indicated that the meta-analytic results were reliable. Similarly, both the case-control study and meta-analysis found no significant association between the MTRR A66G polymorphism and being overweight/obesity. However, sensitivity analyses showed that the associations between the MTRR A66G polymorphism and being overweight/obesity became significant in the dominant, heterozygous codominant and allelic models after excluding our case-control study. The results from our case-control study and meta-analysis suggest that both of the two polymorphisms are not associated with being overweight/obesity. Further large-scale population-based studies, especially for the MTRR A66G polymorphism, are still needed to confirm or refute our findings. PMID:26016497

  17. Association of MTHFR C677T and A1298C polymorphisms with non-Hodgkin lymphoma susceptibility: Evidence from a meta-analysis

    PubMed Central

    He, Jing; Liao, Xiao-Yu; Zhu, Jin-Hong; Xue, Wen-Qiong; Shen, Guo-Ping; Huang, Shao-Yi; Chen, Wei; Jia, Wei-Hua

    2014-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism and DNA synthesis. A number of studies have examined the association of MTHFR C677T and A1298C polymorphisms with non-Hodgkin lymphoma (NHL) susceptibility; however, the conclusions were contradictory. We searched available publications assessing the polymorphisms of MTHFR and NHL susceptibility from MEDLINE, EMBASE and CBM. Genotype-based mRNA expression analysis was performed using data from 270 individuals with three different ethnicities. Ultimately, a total of 7448 cases and 11146 controls from 25 studies were included for the C677T polymorphism, 6173 cases and 9725 controls from 19 studies for the A1298C polymorphism. Pooled results indicated that neither C677T nor A1298C polymorphism was associated with NHL susceptibility. However, C677T polymorphism showed a statistically significantly increased risk for Caucasians, but a decreased risk for Asians in the subgroup analysis by ethnicity. The same variants may confer increased susceptibility to develop follicular lymphoma (FL). Moreover, A1298C polymorphism was associated with increased NHL risk for Asians. This meta-analysis indicated that C677T polymorphism was associated with altered NHL susceptibility for Caucasians, Asians and FL. Increased NHL risk was also shown for A1298C among Asians. These findings warrant validation in large and well-designed prospective studies. PMID:25146845

  18. Methylene Tetrahydrofolate Reductase (MTHFR) rs868014 Polymorphism Regulated by miR-1203 Associates with Risk and Short Term Outcome of Ischemic Stroke.

    PubMed

    He, Wei; Lu, Minzhi; Li, Guoqing; Sun, Zhigang; Liu, Dinghua; Gu, Lujun

    2017-01-01

    Genetic polymorphisms of methylene tetrahydrofolate reductase (MTHFR) were associated with ischemic stroke risk. This study analyzed MTHFR polymorphisms at the 3'-untranslated region for association with risk and outcome of ischemic stroke in a Chinese Han population. 500 patients and 600 healthy volunteers were enrolled for MTHFR rs868014 genotyping identified bioinformatically. The binding of miR-1203 to MTHFR rs868014 was determined by luciferase assay, MTHFR expression was assessed using qRT-PCR, and plasma homocysteine levels were assayed by ELISA. Cigarette smoking, alcohol consumption, diabetes, hypertension (all P <0.001), low levels of serum high-density lipoprotein-C (P = 0.01), and high levels of serum low-density lipoprotein-C (P = 0.005) were associated with an increased risk of developing ischemic stroke. BMI and total serum cholesterol concentration was not associated with ischemic stroke. MTHFR rs868014 TC and CC genotypes were significantly associated with increased risk of ischemic stroke compared with the TT genotype (OR: 1.52; 95% CI: 1.01-3.39 for TC genotype, while OR: 1.99; 95% CI: 1.29-3.88 for CC genotype). Furthermore, the MTHFR rs868014 SNP was associated with a poor short-term ischemic stroke outcome. qRT-PCR confirmed that MTHFR rs868014 TC or CC genotypes could facilitate miR-1203 binding leading to low MTHFR levels in cells. In addition, patients carrying the MTHFR rs868014 TC or CC genotypes were associated with accumulation of serum tHcy and a poor ischemic stroke outcome. Linkage disequilibrium analysis indicated that the newly identified SNP rs868014 was strongly linked with the MTHFR A1298C polymorphism. This study demonstrates that the MTHFR rs868014 SNP is associated with increased risk in developing ischemic stroke, miR-1203 binding, low MTHFR levels in cells, and poor shot term outcome of patients. © 2017 The Author(s)Published by S. Karger AG, Basel.

  19. C677T (RS1801133 ) MTHFR gene polymorphism frequency in a colombian population

    PubMed Central

    Gómez-Gutierrez, Alberto; Gómez, Piedad Elena; Casas-Gomez, Maria Consuelo; Briceño, Ignacio

    2015-01-01

    Introduction: Abnormal levels of the enzyme methylenetetrahydrofolate reductase (MTHFR) are associated with an increased risk of both cardiovascular and cerebrovascular disease and higher concentrations of homocysteine. Abnormal levels are also related to birth defects, pregnancy complications, cancer and toxicity to methotrexate (MTX). Polymorphisms of MTHFR affect the activity of the enzyme. Genetic associations have been related to treatment efficacy. Objective: To establish the frequency of the C> T polymorphism at nucleotide 677 of the MTHFR gene in a group of Colombian individuals. Methods: Data from pharmacogenetic microarrays that include MTX sensibility-associated polymorphisms were retrospectively collected (Pathway Genomics®). The frequency of the C> T MTHFR rs1801133 marker polymorphism was analyzed. Results: Microarray data from 68 men and 84 women were analyzed. Comparisons of genotype C/C vs. C/T and T/T were statistically significantly different (p= 0.00, p= 0.026, respectively), as were C/T and T / T (p= 0.0001). Conclusions: Results for the C/C and C/T genotypes in a Colombian population are similar to other previously studied groups of healthy subjects. Subjects from our population might be at risk of developing diseases associated with MTHFR polymorphisms and might present toxicity and adverse effects if treated with MTX, which suggests the need to evaluate therapeutic alternatives based on individual pharmacogenetic studies. PMID:26309343

  20. C677T (RS1801133 ) MTHFR gene polymorphism frequency in a colombian population.

    PubMed

    Romero-Sánchez, Consuelo; Gómez-Gutierrez, Alberto; Gómez, Piedad Elena; Casas-Gomez, Maria Consuelo; Briceño, Ignacio

    2015-01-01

    Abnormal levels of the enzyme methylenetetrahydrofolate reductase (MTHFR) are associated with an increased risk of both cardiovascular and cerebrovascular disease and higher concentrations of homocysteine. Abnormal levels are also related to birth defects, pregnancy complications, cancer and toxicity to methotrexate (MTX). Polymorphisms of MTHFR affect the activity of the enzyme. Genetic associations have been related to treatment efficacy. To establish the frequency of the C> T polymorphism at nucleotide 677 of the MTHFR gene in a group of Colombian individuals. Data from pharmacogenetic microarrays that include MTX sensibility-associated polymorphisms were retrospectively collected (Pathway Genomics(®)). The frequency of the C> T MTHFR rs1801133 marker polymorphism was analyzed. Microarray data from 68 men and 84 women were analyzed. Comparisons of genotype C/C vs. C/T and T/T were statistically significantly different (p= 0.00, p= 0.026, respectively), as were C/T and T / T (p= 0.0001). Results for the C/C and C/T genotypes in a Colombian population are similar to other previously studied groups of healthy subjects. Subjects from our population might be at risk of developing diseases associated with MTHFR polymorphisms and might present toxicity and adverse effects if treated with MTX, which suggests the need to evaluate therapeutic alternatives based on individual pharmacogenetic studies.

  1. Associations of MTHFR C677T and MTRR A66G gene polymorphisms with metabolic syndrome: a case-control study in Northern China.

    PubMed

    Yang, Boyi; Fan, Shujun; Zhi, Xueyuan; Wang, Da; Li, Yongfang; Wang, Yinuo; Wang, Yanxun; Wei, Jian; Zheng, Quanmei; Sun, Guifan

    2014-11-25

    Prior evidence indicates that homocysteine plays a role in the development of metabolic syndrome (MetS). Methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase reductase (MTRR) A66G polymorphisms are common genetic determinants of homocysteine levels. To investigate the associations of the MTHFR C677T and MTRR A66G polymorphisms with MetS, 692 Chinese Han subjects with MetS and 878 controls were recruited. The component traits of MetS and the MTHFR C677T and MTRR A66G genotypes were determined. A significant association was observed between the MTHFR 677T allele and increased risk of MetS, high fasting blood glucose, high waist circumference, and increasing number of MetS components. The MTRR A66G polymorphism was associated with an increased risk of MetS when combined with the MTHFR 677TT genotype, although there was no association found between MetS and MTRR A66G alone. Furthermore, the MTRR 66GG genotype was associated with high fasting blood glucose and triglycerides. Our data suggest that the MTHFR 677T allele may contribute to an increased risk of MetS in the northern Chinese Han population. The MTRR A66G polymorphism is not associated with MetS. However, it may exacerbate the effect of the MTHFR C677T variant alone. Further large prospective population-based studies are required to confirm our findings.

  2. Associations of MTHFR C677T and MTRR A66G Gene Polymorphisms with Metabolic Syndrome: A Case-Control Study in Northern China

    PubMed Central

    Yang, Boyi; Fan, Shujun; Zhi, Xueyuan; Wang, Da; Li, Yongfang; Wang, Yinuo; Wang, Yanxun; Wei, Jian; Zheng, Quanmei; Sun, Guifan

    2014-01-01

    Prior evidence indicates that homocysteine plays a role in the development of metabolic syndrome (MetS). Methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase reductase (MTRR) A66G polymorphisms are common genetic determinants of homocysteine levels. To investigate the associations of the MTHFR C677T and MTRR A66G polymorphisms with MetS, 692 Chinese Han subjects with MetS and 878 controls were recruited. The component traits of MetS and the MTHFR C677T and MTRR A66G genotypes were determined. A significant association was observed between the MTHFR 677T allele and increased risk of MetS, high fasting blood glucose, high waist circumference, and increasing number of MetS components. The MTRR A66G polymorphism was associated with an increased risk of MetS when combined with the MTHFR 677TT genotype, although there was no association found between MetS and MTRR A66G alone. Furthermore, the MTRR 66GG genotype was associated with high fasting blood glucose and triglycerides. Our data suggest that the MTHFR 677T allele may contribute to an increased risk of MetS in the northern Chinese Han population. The MTRR A66G polymorphism is not associated with MetS. However, it may exacerbate the effect of the MTHFR C677T variant alone. Further large prospective population-based studies are required to confirm our findings. PMID:25429430

  3. Geographical and Ethnic Distributions of the MTHFR C677T, A1298C and MTRR A66G Gene Polymorphisms in Chinese Populations: A Meta-Analysis.

    PubMed

    Wang, Xingmin; Fu, Jinjian; Li, Qianxi; Zeng, Dingyuan

    2016-01-01

    The geographical and ethnic distributions of the polymorphic methylenetetrahydrofolate reductase (MTHFR) mutations (C677T and A1298C) and methionine synthase reductase (MTRR) mutation (A66G) remain heterogeneous in China. The goal of this study was to estimate the pooled frequencies of the alleles and associated genotypes of these gene polymorphisms among healthy populations in Mainland China. We systematically reviewed published epidemiological studies on the distributions of 3 genetic variants in Chinese healthy populations living in Mainland China through a meta-analysis. The relevant electronic databases were searched. All of the raw data of the eligible citations were extracted. The frequency estimates were stratified by geography, ethnicity and sex. Sixty-six studies were identified with a total of 92277 study participants. The meta-analysis revealed that the frequencies of the MTHFR C677T, A1298C, and MTRR A66G gene polymorphisms varied significantly between different ethnic groups and along geographical gradients. The frequencies of the 677T allele and 677TT genotype increased along the southern-central-northern direction across Mainland China (all Pvalues≤0.001). The frequencies of the 1298C, 1298CC, 66G and 66GG genotypes decreased along the south-central-north direction across the country (all Pvalues≤0.001). Our meta-analysis strongly indicates significant geographical and ethnic variations in the frequencies of the C677T, A1298C, and A66G gene polymorphisms in the folate metabolism pathway among Chinese populations.

  4. Anthracycline-Related Cardiomyopathy After Childhood Cancer: Role of Polymorphisms in Carbonyl Reductase Genes—A Report From the Children's Oncology Group

    PubMed Central

    Blanco, Javier G.; Sun, Can-Lan; Landier, Wendy; Chen, Lu; Esparza-Duran, Diego; Leisenring, Wendy; Mays, Allison; Friedman, Debra L.; Ginsberg, Jill P.; Hudson, Melissa M.; Neglia, Joseph P.; Oeffinger, Kevin C.; Ritchey, A. Kim; Villaluna, Doojduen; Relling, Mary V.; Bhatia, Smita

    2012-01-01

    Purpose Carbonyl reductases (CBRs) catalyze reduction of anthracyclines to cardiotoxic alcohol metabolites. Polymorphisms in CBR1 and CBR3 influence synthesis of these metabolites. We examined whether single nucleotide polymorphisms in CBR1 (CBR1 1096G>A) and/or CBR3 (CBR3 V244M) modified the dose-dependent risk of anthracycline-related cardiomyopathy in childhood cancer survivors. Patients and Methods One hundred seventy survivors with cardiomyopathy (patient cases) were compared with 317 survivors with no cardiomyopathy (controls; matched on cancer diagnosis, year of diagnosis, length of follow-up, and race/ethnicity) using conditional logistic regression techniques. Results A dose-dependent association was observed between cumulative anthracycline exposure and cardiomyopathy risk (0 mg/m2: reference; 1 to 100 mg/m2: odds ratio [OR], 1.65; 101 to 150 mg/m2: OR, 3.85; 151 to 200 mg/m2: OR, 3.69; 201 to 250 mg/m2: OR, 7.23; 251 to 300 mg/m2: OR, 23.47; > 300 mg/m2: OR, 27.59; Ptrend < .001). Among individuals carrying the variant A allele (CBR1:GA/AA and/or CBR3:GA/AA), exposure to low- to moderate-dose anthracyclines (1 to 250 mg/m2) did not increase the risk of cardiomyopathy. Among individuals with CBR3 V244M homozygous G genotypes (CBR3:GG), exposure to low- to moderate-dose anthracyclines increased cardiomyopathy risk when compared with individuals with CBR3:GA/AA genotypes unexposed to anthracyclines (OR, 5.48; P = .003), as well as exposed to low- to moderate-dose anthracyclines (OR, 3.30; P = .006). High-dose anthracyclines (> 250 mg/m2) were associated with increased cardiomyopathy risk, irrespective of CBR genotype status. Conclusion This study demonstrates increased anthracycline-related cardiomyopathy risk at doses as low as 101 to 150 mg/m2. Homozygosis for G allele in CBR3 contributes to increased cardiomyopathy risk associated with low- to moderate-dose anthracyclines, such that there seems to be no safe dose for patients homozygous for the CBR3 V244

  5. Dihydrofolate reductase 19-bp deletion polymorphism modifies the association of folate status with memory in a cross-sectional multi-ethnic study of adults123

    PubMed Central

    Philip, Dana; Buch, Assaf; Moorthy, Denish; Scott, Tammy M; Parnell, Laurence D; Lai, Chao-Qiang; Ordovás, José M; Selhub, Jacob; Rosenberg, Irwin H; Tucker, Katherine L; Troen, Aron M

    2015-01-01

    Background: Folate status has been positively associated with cognitive function in many studies; however, some studies have observed associations of poor cognitive outcomes with high folate. In search of an explanation, we hypothesized that the association of folate with cognition would be modified by the interaction of high-folate status with a common 19-bp deletion polymorphism in the dihydrofolate reductase (DHFR) gene. To our knowledge, the cognitive effects of this gene have not been studied previously. Objective: We examined the association between cognitive outcomes with the 19-bp deletion DHFR polymorphism, folate status, and their interaction with high or normal plasma folate. Design: This was a pooled cross-sectional study of the following 2 Boston-based cohorts of community living adults: the Boston Puerto Rican Health Study and the Nutrition, Aging, and Memory in Elders study. Individuals were genotyped for the DHFR 19-bp deletion genotype, and plasma folate status was determined. Cognitive outcomes included the Mini-Mental State Examination, Center for Epidemiologic Studies Depression Scale, and factor scores for the domains of memory, executive function, and attention from a set of cognitive tests. Results: The prevalence of the homozygous deletion (del/del) genotype was 23%. In a multivariable analysis, high folate status (>17.8 ng/mL) was associated with better memory scores than was normal-folate status (fourth–fifth quintiles compared with first–third quintiles: β ± SE = −0.22 ± 0.06, P < 0.01). Carriers of the DHFR del/del genotype had worse memory scores (β ± SE = −0.24 ± 0.10, P < 0.05) and worse executive scores (β = −0.19, P < 0.05) than did those with the del/ins and ins/ins genotypes. Finally, we observed an interaction such that carriers of the del/del genotype with high folate had significantly worse memory scores than those of both noncarriers with high-folate and del/del carriers with normal-folate (β-interaction = 0

  6. No association between MTHFR A1298C and MTRR A66G polymorphisms, and MS in an Australian cohort.

    PubMed

    Szvetko, A L; Fowdar, J; Nelson, J; Colson, N; Tajouri, L; Csurhes, P A; Pender, M P; Griffiths, L R

    2007-01-15

    Multiple sclerosis (MS) is a complex neurological disease that affects the central nervous system (CNS) resulting in debilitating neuropathology. Pathogenesis is primarily defined by CNS inflammation and demyelination of nerve axons. Methionine synthase reductase (MTRR) is an enzyme that catalyzes the remethylation of homocysteine (Hcy) to methionine via cobalamin and folate dependant reactions. Cobalamin acts as an intermediate methyl carrier between methylenetetrahydrofolate reductase (MTHFR) and Hcy. MTRR plays a critical role in maintaining cobalamin in an active form and is consequently an important determinant of total plasma Hcy (pHcy) concentrations. Elevated intracellular pHcy levels have been suggested to play a role in CNS dysfunction, neurodegenerative, and cerebrovascular diseases. Our investigation entailed the genotyping of a cohort of 140 cases and matched controls for MTRR and MTHFR, by restriction length polymorphism (RFLP) techniques. Two polymorphisms: MTRR A66G and MTHFR A1298C were investigated in an Australian age and gender matched case-control study. No significant allelic frequency difference was observed between cases and controls at the alpha = 0.05 level (MTRR chi2 = 0.005, P = 0.95, MTHFR chi2 = 1.15, P = 0.28). Our preliminary findings suggest no association between the MTRR A66G and MTHFR A1298C polymorphisms and MS.

  7. Folate Deficiency and Gene Polymorphisms of MTHFR, MTR and MTRR Elevate the Hyperhomocysteinemia Risk.

    PubMed

    Li, Wen-Xing; Cheng, Fei; Zhang, A-Jie; Dai, Shao-Xing; Li, Gong-Hua; Lv, Wen-Wen; Zhou, Tao; Zhang, Qiang; Zhang, Hong; Zhang, Tao; Liu, Fang; Liu, Dahai; Huang, Jing-Fei

    2017-03-01

    Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular diseases (CVDs). We aimed to investigate the joint effect of homocysteine metabolism gene polymorphisms, as well as the folate deficiency on the risk of HHcy in a Chinese hypertensive population. This study enrolled 480 hypertensive patients aged 28 - 75 from six hospitals in different Chinese regions from 9/2005 - 12/2005. Known genotypes of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, and methionine synthase reductase (MTRR) A66G were detected by PCRRFLP methods. Serum Hcy was measured by high-performance liquid chromatography and serum folate was measured by chemiluminescent immunoassay. MTHFR C677T and MTR A2756G can independently elevate the risk of HHcy (TT vs. CC + CT, p < 0.001 and AG + GG vs. AA, p = 0.026, respectively), whereas MTHFR A1298C decreased HHcy risk (AC + CC vs. AA, p < 0.001) and showed a protective effect against HHcy risk. Importantly, the joint effect of these risk genotypes showed significantly higher odds of HHcy than non-risk genotypes, especially the patients with four risk genotypes. It is noteworthy that this deleterious effect was aggravated by folate deficiency. These findings were verified by generalized multifactor dimensionality reduction model (p = 0.001) and a cumulative effects model (p < 0.001). We have first demonstrated that the joint effect of homocysteine metabolism gene polymorphisms and folate deficiency lead to dramatic elevations in the HHcy risk.

  8. [Geographical distribution of MTHFR and MTRR gene polymorphisms among the Han women in Zhengzhou city].

    PubMed

    Cui, Huiling; Lu, Yanqiang; Ma, Shaojie; Xue, Yan; Wang, Ting; Duan, Gehong; Yang, Qi

    2015-07-01

    To explore the genotype distribution of 5,10-methylenetetrahydrofolate reductase (MTHFR) and 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR) among Chinese Han women in Zhengzhou. 
 A total of 1 253 women were recruited from Zhengzhou city. The genotype of MTHFR C677T, A1298C and MTRR A66G was detected to analyze the distribution of gene polymorphisms and to compare them with the published data from other Han women.
 The frequency of the MTHFR 1298CC genotypes (1.3%) in Zhengzhou was lower than that in Xiangtan (4.8%), Yanbian (3.8%), Zhenjiang (3.5%), Jingzhou (3.2%), Kunming (2.7%), Deyang (6.3%), Huizhou (7.2%) and Wulumuqi (3.4%) (all P<0.05). The difference in allele frequency was significant compared with that in Yantai, Yanbian, Wulumuqi, Zhenjiang, Jingzhou, Kunming, Dezhou, Xiangtan or Huizhou (all P<0.05). The frequency of the MTRR 66GG genotypes (5.4%) in Zhengzhou was lower than that in Deyang (8.2%) (P<0.01) and allele frequency between them was significant difference (P<0.05). 
 The gene polymorphism of MTHFR A1298C and MTRR A66G among the Han women in Zhengzhou is statistically different from that in some regions of China.

  9. A Study on MTHFR C677T Gene Polymorphism and Alcohol Dependence among Meiteis of Manipur, India.

    PubMed

    Singh, Huidrom Suraj; Salam, Kabita; Saraswathy, Kallur Nava

    2014-01-01

    Chronic alcohol consumption is reported to be associated with increase in plasma homocysteine levels which is further influenced by the polymorphism in methylenetetrahydrofolate reductase (MTHFR) gene. The present study aims to understand the extent of the MTHFR C677T polymorphism in alcohol dependent (AD) cases of Meiteis of Manipur, a Mendelian population of India. MTHFR C677T polymorphism was screened in 313 controls and 139 alcohol dependent (AD) cases who all met DSM-IV criteria for alcohol dependence. Both AD cases and controls were unrelated up to 1st cousin. Among the control group, different drinking patterns like abstainer/nondrinkers (NDs), occasional drinkers (ODs), and moderate drinkers (MDs) are included. Both the groups were found to be in Hardy-Weinberg equilibrium (P > 0.05). Genotypic and allelic frequency distribution of MTHFR C677T polymorphism did not differ significantly between AD cases and controls (P > 0.05). However, individuals carrying mutant (T) allele show more than 1-fold increased risk for AD though not significant (OR = 1.43; 95% CI 0.41-5.01, P > 0.05). In conclusion, MTHFR C677T polymorphism is not found to be risk marker for AD in present studied population. However, higher prevalence of the mutant T allele may exacerbate deleterious health risk in future especially among alcohol drinkers.

  10. Association of MTHFR C677T polymorphism with loneliness but not depression in cognitively normal elderly males.

    PubMed

    Lan, Wen-Hsuan; Yang, Albert C; Hwang, Jen-Ping; Hong, Chen-Jee; Liou, Ying-Jay; Yeh, Heng-Liang; Liu, Mu-En; Tsai, Shih-Jen

    2012-07-11

    Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is involved in folate and homocysteine metabolism, and has been associated with geriatric disorders, including dementia and late-life depression. The present work aimed to investigate the effect of MTHFR C677T polymorphism on the presence of depression and loneliness in cognitively normal male subjects. A total of 323 cognitively normal male subjects were included in this study (mean age=80.6; SD=5.3). Depression was assessed by the Geriatric Depression Scale-Short Form (GDS-SF) and loneliness by UCLA loneliness scales. Analysis of variance (ANOVA) was used to test the between MTHFR genotype difference in depression and loneliness. Multiple regression was used to test the effect of MTHFR polymorphism on the loneliness, controlling for age, education, cognitive function, and depression. ANOVA showed a significant between-genotype difference in loneliness scores (P=0.015), and post hoc comparisons showed that subjects with C/C genotype had significantly higher loneliness ratings, compared to those with C/T or T/T genotype. Regression analysis indicated that the effect of MTHFR polymorphism on loneliness was independent of age, education, cognitive function, and depression. Our findings suggest that MTHFR C677T polymorphism may be linked more to loneliness than depression in the cognitively normal elderly males, and may be implicated in the pathophysiology of late-life depression in relation to MTHFR genes.

  11. Epistasis Between Polymorphisms in COMT, ESR1, and GCH1 Influences COMT Enzyme Activity and Pain

    PubMed Central

    Smith, Shad B.; Reenilä, Ilkka; Männistö, Pekka T.; Slade, Gary D.; Maixner, William; Diatchenko, Luda; Nackley, Andrea G.

    2014-01-01

    Abnormalities in the enzymatic activity of catechol-O-methyltransferase (COMT) contribute to chronic pain conditions, such as temporomandibular disorders (TMD). Thus, we sought to determine the effects of polymorphisms in COMT and functionally-related pain genes in the COMT pathway (estrogen receptor 1: ESR1, guanosine-5-triphosphate cyclohydrolase 1: GCH1, methylenetetrahydrofolate reductase: MTHFR) on COMT enzymatic activity, musculoskeletal pain, and pain-related intermediate phenotypes among TMD cases and healthy controls. Results demonstrate that the COMT rs4680 (val158met) polymorphism is most strongly associated with outcome measures, such that individuals with the minor A allele (met) exhibit reduced COMT activity, increased TMD risk, and increased musculoskeletal pain. Epistatic interactions were observed between the COMT rs4680 polymorphism and polymorphisms in GCH1 and ESR1. Among individuals with the COMT met allele, those with two copies of the GCH1 rs10483639 minor G allele exhibit normalized COMT activity and increased mechanical pain thresholds. Among individuals with the COMT val allele, those with two copies of the ESR1 rs3020377 minor A allele exhibit reduced COMT activity, increased bodily pain, and poorer self-reported health. These data reveal that the GCH1 minor G allele confers a protective advantage among met carriers, while the ESR1 minor A allele is disadvantageous among val carriers. Furthermore, these data suggest that the ability to predict the downstream effects of genetic variation on COMT activity is critically important to understanding the molecular basis of chronic pain conditions. PMID:25218601

  12. Epistasis between polymorphisms in COMT, ESR1, and GCH1 influences COMT enzyme activity and pain.

    PubMed

    Smith, Shad B; Reenilä, Ilkka; Männistö, Pekka T; Slade, Gary D; Maixner, William; Diatchenko, Luda; Nackley, Andrea G

    2014-11-01

    Abnormalities in the enzymatic activity of catechol-O-methyltransferase (COMT) contribute to chronic pain conditions, such as temporomandibular disorders (TMD). Thus, we sought to determine the effects of polymorphisms in COMT and functionally related pain genes in the COMT pathway (estrogen receptor 1 [ESR1], guanosine-5-triphosphate cyclohydrolase 1 [GCH1], methylenetetrahydrofolate reductase [MTHFR]) on COMT enzymatic activity, musculoskeletal pain, and pain-related intermediate phenotypes among TMD cases and healthy control subjects. Results show that the COMT rs4680 (val(158)met) polymorphism is most strongly associated with outcome measures, such that individuals with the minor A allele (met) exhibit reduced COMT activity, increased TMD risk, and increased musculoskeletal pain. Epistatic interactions were observed between the COMT rs4680 polymorphism and polymorphisms in GCH1 and ESR1. Among individuals with the COMT met allele, those with 2 copies of the GCH1 rs10483639 minor G allele exhibit normalized COMT activity and increased mechanical pain thresholds. Among individuals with the COMT val allele, those with 2 copies of the ESR1 rs3020377 minor A allele exhibit reduced COMT activity, increased bodily pain, and poorer self-reported health. These data reveal that the GCH1 minor G allele confers a protective advantage among met carriers, whereas the ESR1 minor A allele is disadvantageous among val carriers. Furthermore, these data suggest that the ability to predict the downstream effects of genetic variation on COMT activity is critically important to understanding the molecular basis of chronic pain conditions.

  13. Association of MTHFR C677T and A1298C polymorphisms with oral cancer susceptibility: evidence from a meta-analysis

    PubMed Central

    Jiang, Sui; Xu, Jin-Dong; Zhuo, Zhen-Jian; Hua, Zhu-Ming

    2017-01-01

    Methylenetetrahydrofolate reductase (MTHFR) is a central enzyme involved in folate metabolism and plays an important role in DNA synthesis and methylation. Several studies have been conducted to illustrate the associations between MTHFR C677T and A1298C polymorphisms with oral cancer susceptibility; however, the results are inconsistent. Therefore, we conducted an updated meta-analysis to obtain a more reliable estimation of the associations. We retrieved eligible studies from PubMed, EMBASE, and CBM databases through September 2016. Ultimately, pooled analyses involved 10 studies with 1443 cases and 1640 controls for the C677T polymorphism, as well as five studies with 973 cases and 1024 controls for the A1298C polymorphism. Risk estimates were presented as odds ratios (ORs) and 95% confidence intervals (95% CIs). Pooled results indicated that neither C677T nor A1298C polymorphism was associated with oral cancer susceptibility. However, a borderline significant association was detected between MTHFR C677T polymorphism and a decreased oral cancer risk (homozygous model: OR=0.71, 95% CI=0.50–1.00) in hospital-based studies. Our results suggested that MTHFR C677T and A1298C polymorphisms might not be associated with oral cancer risk. However, more evidence is needed to further confirm these findings in the future. PMID:28138253

  14. Polymorphism of SLC25A32, the folate transporter gene, is associated with plasma folate levels and bone fractures in Japanese postmenopausal women.

    PubMed

    Urano, Tomohiko; Shiraki, Masataka; Saito, Mitsuru; Sasaki, Noriko; Ouchi, Yasuyoshi; Inoue, Satoshi

    2014-10-01

    Elevation of homocysteine is associated with an increased risk for bone fractures. We previously reported that the methylenetetrahydrofolate reductase (MTHFR) gene polymorphism is associated with homocysteine levels and fracture. The association between the fracture and folate levels or their related gene polymorphisms is not completely clear. We speculated that the SLC25A32 gene, the mitochondrial inner membrane folate transporter, also could be implicated in the regulation of folate metabolism and fracture. A total of 851 Japanese postmenopausal women participated in the association study between the single nucleotide polymorphism genotype and plasma homocysteine or folate. We also tested the association between the candidate single nucleotide polymorphism and 663 postmenopausal women. The AA genotype of rs2241777 single nucleotide polymorphism at the 3'UTR region in the SLC25A32 gene was associated with lower plasma folate concentration compared with the other genotypes in 851 postmenopausal women. A total of 674 postmenopausal ambulatory Japanese women were followed up for 5.5 ± 0.1 years (mean ± SE). The AA genotype groups also showed an apparently higher rate and earlier onset of incident fractures than the other genotypes. A total of 407 participants had >70% young-adult mean bone mineral density at the start of the observation. These results show that the SLC25A32 gene polymorphism could be a risk factor for lower folate concentration and future fracture. © 2013 Japan Geriatrics Society.

  15. MTHFR C677 T gene polymorphism in lymphoproliferative diseases.

    PubMed

    Deligezer, Ugur; Akisik, Ebru E; Yaman, Fulya; Erten, Nilgün; Dalay, Nejat

    2006-01-01

    Methylenetetrahydrofolate reductase (MTHFR), a key enzyme in folate metabolism, has been implicated in cancer risk. In the present study we used a melting curve analysis to investigate the association of the common MTHFR C677 T polymorphism with lymphoproliferative diseases. Patients (n=117) were compared with age- and sex-matched control subjects (n=154). Our results indicate that the 677 T variant occurred less frequently in patients (26%) than in the control group (33.7%; P=0.05). Investigation of the variant allele (677 T) frequency in the subgroups with Hodgkin's lymphoma (HL) and B-cell neoplasms (BCNs) revealed that this difference was a result of the significantly lower distribution of the variant allele in patients with HL (20.5%; P=0.01). This was accompanied by a significantly higher frequency of the homozygote normal genotype (677CC) among the patients with HL. In patients with BCNs the distribution of the variant allele (30.3%) was comparable to that in the control group (P=0.47). However, the difference between HL (20.5%) and BCNs (30.3%) did not reach statistical significance (P=0.09). Our results suggest that the distribution of the C677 T polymorphism may vary among lymphoproliferative diseases.

  16. Risk of prostate cancer and thrombosis-related factor polymorphisms

    PubMed Central

    GHASEMI, SOMAYEHSADAT; TAVAKOLI, AYDIN; MOGHADAM, MOHAMAD; ZARGAR, MOHAMAD ALI; ABBASPOUR, MARYAM; HATAMNEJADIAN, NASIM; EBRAHIMI, AHMAD

    2014-01-01

    Venous thromboembolism (VTE) is a complication commonly encountered in cancer patients and is considered to be a major cause of morbidity and mortality. The genetic polymorphisms of thrombophilic factors in cancer patients have been focused on during the last few years. However, the number of available studies on the association between prostate cancer and thromboembolic diseases is limited. Prostate cancer is one of the four major types of cancer and its development is affected by a variety of environmental and genetic factors. In the present study we aimed to focus on the effects of thromboembolic factor gene variations on the risk of prostate cancer. In order to conduct our prospective study, we used amplification-refractory mutation system-polymerase chain reaction to investigate three polymorphisms [factor V Leiden (FVL) G1691A, factor II (prothrombin, PTH) G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T] in prostate cancer patients, via comparison with normal individuals. The results demonstrated no significant differences in FVL and PTH gene variations between cases and controls (P>0.05). Although some cases with the T allele of MTHFR 677 were identified, no significant solidarity was established by statistical analysis (P>0.05). Therefore, non-genetic factors that may disturb homeostatic balance should also be considered in future studies, in order to determine the exact association between VTE and prostate cancer. PMID:24649068

  17. Association among polymorphisms in the steroid 5alpha-reductase type II (SRD5A2) gene, prostate cancer risk, and pathologic characteristics of prostate tumors in an Ecuadorian population.

    PubMed

    Paz-y-Miño, César; Witte, Tania; Robles, Paulo; Llumipanta, William; Díaz, Myriam; Arévalo, Melissa

    2009-03-01

    Androgens are essential to normal prostate growth and development. It is therefore possible that polymorphisms in the androgen synthesis gene 5alpha-reductase type II (SRD5A2) may be involved in the progression of prostate tumors. We evaluated the relationship of two single-nucleotide polymorphisms, A49T and V89L, with prostate cancer risk in a case-control study. A total of 114 prostate cancer patients and 144 healthy control males were genotyped. We found highly significant differences between the two polymorphisms, the risk of developing prostate cancer, and some of the clinical-pathologic characteristics. Individuals who carry at least one V allele may have a higher risk of developing prostate cancer [odds ratio (OR) = 7.5, 95% confidence interval (CI) = 2.57-22.08, P<0.001]. In addition, individuals with LL genotype showed reduction in the progression to a higher tumor stage (OR = 0.10, 95%CI = 0.040-0.27, P<0.001). The A49T substitution was associated with a higher pTNM stage (OR = 2.87, 95%CI 1.14-7.21, P = 0.003) and elevated Gleason grade (OR = 3.14, 95%CI = 1.12-8.78; P = 0.004). Furthermore, the allelic frequencies of the A49T variant (33% controls and 45% cases) are the highest reported worldwide. These findings suggest that among the Ecuadorian population, these polymorphisms influence the risk of developing prostate cancer.

  18. Association between decreased vitamin levels and MTHFR, MTR and MTRR gene polymorphisms as determinants for elevated total homocysteine concentrations in pregnant women.

    PubMed

    Barbosa, P R; Stabler, S P; Machado, A L K; Braga, R C; Hirata, R D C; Hirata, M H; Sampaio-Neto, L F; Allen, R H; Guerra-Shinohara, E M

    2008-08-01

    To examine the association between methylenetetrahydrofolate reductase (MTHFR) (C677T and A1298C), methionine synthase (MTR) A2756G and methionine synthase reductase (MTRR) A66G gene polymorphisms and total homocysteine (tHcy), methylmalonic acid (MMA) and S-adenosylmethionine/S-adenosylhomocysteine (SAM/SAH) levels; and to evaluate the potential interactions with folate or cobalamin (Cbl) status. Two hundred seventy-five healthy women at labor who delivered full-term normal babies. Cbl, folate, tHcy, MMA, SAM and SAH were measured in serum specimens. The genotypes for polymorphisms were determined by PCR-restriction fragment length polymorphism (RFLP). Serum folate, MTHFR 677T allele and MTR 2756AA genotypes were the predictors of tHcy levels in pregnant women. Serum Cbl and creatinine were the predictors of SAM/SAH ratio and MMA levels, respectively. The gene polymorphisms were not determinants for MMA levels and SAM/SAH ratios. Low levels of serum folate were associated with elevated tHcy in pregnant women, independently of the gene polymorphisms. In pregnant women carrying MTHFR 677T allele, or MTHFR 1298AA or MTRR 66AA genotypes, lower Cbl levels were associated with higher levels of tHcy. Lower SAM/SAH ratio was found in MTHFR 677CC or MTRR A2756AA genotypes carriers when Cbl levels were lower than 142 pmol/l. Serum folate and MTHFR C677T and MTR A2576G gene polymorphisms were the determinants for tHcy levels. The interaction between low levels of serum Cbl and MTHFR (C677T or A1298C) or MTRR A66G gene polymorphisms was associated with increased tHcy.

  19. Possible selection of host folate pathway gene polymorphisms in patients with malaria from a malaria endemic region in North East India

    PubMed Central

    Mirgal, Darshana; Ghosh, Kanjaksha; Mahanta, Jagadish; Dutta, Prafulla; Shetty, Shrimati

    2016-01-01

    Background Recent studies in experimental mice have shown that mild deficiency of methylenetetrahydrofolate reductase (MTHFR) enzyme confers protection against malaria, thus providing an important basis for the hypothesis that MTHFR polymorphism, i.e. C677T, might have been subjected to selection pressure against malaria. The present study was undertaken in a malaria endemic region in North East India to assess whether a similar selection advantage exists for other genes in folate metabolism pathway. Methods A total of 401 subjects including 131 symptomatic malaria, 97 asymptomatic malaria and 173 normal healthy controls were analysed for nine polymorphisms (single-nucleotide polymorphisms [SNPs] in eight genes and insertion/deletion in one gene): MTHFR C677T, methionine synthase reductase (MTRR) A66G, glutamate carboxypeptidase II (GCPII) C1561T, cystathionine beta-synthase (CBS) 844ins68, reduced folate carrier-1 (RFC-1) G80A, serine hydroxymethyltransferase (SHMT) C1420T, methionine synthase (MTR) A2756G, MTHFR G1793A (D 919G), glycine N-methyltransferase (GNMT) 1289 by PCR-RFLP technique. Differences in frequencies of genotype distribution of each polymorphic marker between these groups were evaluated. Results MTRR A2756G, SHMT C1420T, GCPII C1561T, MTRR A2756G and GNMT C1289T and RFC1 G80A polymorphisms showed significantly different prevalence between different groups analyzed. No significant differences were seen in the distribution of other polymorphisms. Conclusions The study gives a clue for the possible selection of specific polymorphisms in the genes involved in the folate metabolism pathway by malaria parasite. PMID:27198213

  20. Association of MTHFR C677T polymorphism with bone mineral density of osteoporosis in postmenopausal Thai women.

    PubMed

    Tongboonchoo, Chutaporn; Tungtrongchitr, Anchalee; Phonrat, Benjaluck; Preutthipan, Sangchai; Tungtrongchitr, Rungsunn

    2013-02-01

    Osteoporosis and osteopenia is rising with the increase in numbers of postmenopausal women. Methylenetetrahydrofolate reductase (MTHFR), a homocysteine catabolizing enzyme, is involved in the regulation of bone mineral density (BMD). The association between MTHFR C677T polymorphism with osteoporosis in postmenopausal Thai women is hitherto unclear. To investigate the association between MTHFR C677T and BMD in postmenopausal Thai women. The study subjects consisted of 346 postmenopausal Thai women volunteers. Standard dual-energy X-ray absorptiometry (DXA) was used for measurement of BMD T-score. Restriction fragment length polymorphism (RFLP) analysis was used for measurement of MTHFR C677T polymorphism. In the evaluation of 346 postmenopausal Thai women heterozygous (CT) genotype had a risk of osteopenia than normal control (odds ratio (OR) = 5.66, p < 0.001). BMD T-scores at each bone position revealed that heterozygous (CT) genotype had increased risk of osteopenic bones than normal controls at lumbar spines 1, 2, and 4 (OR = 2.48, p < 0.001, OR = 1.98, p = 0.008 and OR = 1.83, p = 0.016 respectively), ward's triangle (OR = 2.08, p = 0.008), and head of radius (OR = 2.95, p = 0.008). These results indicate the possibility of using MTHFR C677T polymorphism to identify postmenopausal Thai women at high risk of osteopenia.

  1. Does the MTHFR A1298C Polymorphism Modulate the Cardiorespiratory Response to Training?

    PubMed

    Cięszczyk, Paweł; Zarębska, Aleksandra; Jastrzębski, Zbigniew; Sawczyn, Michał; Kozakiewicz-Drobnik, Izabela; Leońska-Duniec, Agata; Kaczmarczyk, Mariusz; Maciejewska-Skrendo, Agnieszka; Żmijewski, Piotr; Trybek, Grzegorz; Smółka, Wojciech; Pilch, Jan; Leźnicka, Katarzyna; Lulińska-Kuklik, Ewelina; Sawczuk, Marek; Massidda, Myosotis

    2016-12-01

    The 5,10-methylenetetrahydrofolate reductase gene (MTHFR) A1298C polymorphic variant is a candidate to explain the individual differences in trainability and response to exercise training. Therefore, the aim of the study was to verify whether the A1298C polymorphism influenced the aerobic and anaerobic performance as well as body and mass composition in young Polish women following low-high impact aerobic exercise training. Two hundred and one women aged 21 ± 1 years (range 19-24) were included in the study. All of them completed a 12-week exercise training program and were measured for selected somatic features, aerobic capacity and cardiorespiratory fitness indices as well as peak anaerobic power and anaerobic capacity, before and after the intervention. A mixed 2 x 2 ANOVA for 20 dependent variables grouped in three categories was conducted. No significant interaction of the genotype with training for body mass and body composition variables was observed. Although, there were three significant genotype x training interactions for maximal oxygen uptake variables, regardless of body mass i.e.: for VO2max (p < 0.05), HRmax (p < 0.0001) and HRAT/HRmax (p < 0.0001). Significantly greater improvement in VO2max was gained by the CC+AC group compared to the AA genotype group. The present results support the hypothesis that individual differences in trainability are at least in part determined by the genetic component and MTHFR A1298C seems to be one of the many polymorphisms involved.

  2. Dietary consumption of B vitamins, maternal MTHFR polymorphisms and risk for spontaneous abortion

    PubMed Central

    Rodríguez-Guillén, María del Rosario; Torres-Sánchez, Luisa; Chen, Jia; Galván-Portillo, Marcia; Silva-Zolezzi, Irma; Blanco-Muñoz, Julia; Hernández-Valero, María A.; López-Carrillo, Lizbeth

    2010-01-01

    Objective To asses he association between intake of folate and B vitamins and the incidence of spontaneous abortion (SA) according to the maternal methylenetetrahydrofolate reductase (MTHFR) polymorphisms (677 C>T and 1298 A>C). Material and Methods We conducted a nested case-control study within a perinatal cohort of women recruited in the state of Morelos, Mexico. Twenty-three women with SA were compared to 74 women whose pregnancy survived beyond week 20th. Intake of folate and B vitamins respectively, was estimated using a validated food frequency questionnaire. Maternal MTHFR polymorphisms were determined by PCR-RFLP and serum homocysteine levels by HPLC. Results Carriers of MTHFR 677TT and 1298AC genotypes respectively showed an increased risk of SA (OR 677TT vs. CC/CT=5.0; 95% CI: 1.2, 20.9 and OR 1298 AC vs. AA=5.5; 95% CI: 1.1, 26.6). Conclusions Our results support the role of MTHFR polymorphisms as a risk factor for SA, regardless of dietary intake of B vitamins. PMID:19180309

  3. A 19-base pair deletion polymorphism in dihydrofolate reductase is associated with increased unmetabolized folic acid in plasma and decreased red blood cell folate

    USDA-ARS?s Scientific Manuscript database

    Dihydrofolate reductase (DHFR) catalyzes the reduction of folic acid to tetrahydrofolate (THF). A 19-bp noncoding deletion allele maps to intron 1, beginning 60 bases from the splice donor site, and has been implicated in neural tube defects and cancer, presumably by influencing folate metabolism. T...

  4. MTHFR 677C>T polymorphism and cluster headache.

    PubMed

    Schürks, Markus; Neumann, Franziska A; Kessler, Christof; Diener, Hans-Christoph; Kroemer, Heyo K; Kurth, Tobias; Völzke, Henry; Rosskopf, Dieter

    2011-02-01

    An association between the 677C>T polymorphism (rs1801133) in the methylenetetrahydrofolate reductase gene (MTHFR) and cluster headache is plausible, but has not been investigated. To investigate this association among Caucasians. Case-control study among 147 cluster headache patients and 599 population-based age- and gender-matched controls. Cluster headache was diagnosed according to the criteria of the International Headache Society. Genotypes of the MTHFR 677C>T polymorphism were detected by restriction fragment length polymorphism analysis. We used logistic regression analysis to investigate the association between cluster headache and genotypes with additive, dominant, and recessive models. We considered a Bonferroni-corrected P value <.004 as significant. Mean age at study entry among patients was 44.9 years (SD 11.4), of whom 76.2% were men. The genotype distribution among controls and patients was in Hardy-Weinberg equilibrium. The genotype and allele distribution did not differ between patients with any cluster headache and controls. We also did not find an association when assuming additive, dominant or recessive genetic models. When we looked at subgroups, the effect estimates suggested an increased risk for chronic cluster headache (dominant model: odds ratio = 2.82; 99.6% confidence interval = 0.72-11.07; P = .03). Data from our case-control study do not indicate an association between genotypes of the MTHFR 677C>T polymorphism and cluster headache overall. Subgroup analyses suggested that carriers of the MTHFR 677T allele may have an increased risk for chronic cluster headache. This may be regarded as hypothesis-generating and should be further investigated in independent studies. © 2010 American Headache Society.

  5. MAOA, MTHFR, and TNF-β genes polymorphisms and personality traits in the pathogenesis of migraine.

    PubMed

    Ishii, Masakazu; Shimizu, Shunichi; Sakairi, Yuki; Nagamine, Ayumu; Naito, Yuika; Hosaka, Yukiko; Naito, Yuko; Kurihara, Tatsuya; Onaya, Tomomi; Oyamada, Hideto; Imagawa, Atsuko; Shida, Kenji; Takahashi, Johji; Oguchi, Katsuji; Masuda, Yutaka; Hara, Hajime; Usami, Shino; Kiuchi, Yuji

    2012-04-01

    Migraine is a multifactorial disease with various factors, such as genetic polymorphisms and personality traits, but the contribution of those factors is not clear. To clarify the pathogenesis of migraine, the contributions of genetic polymorphisms and personality traits were simultaneously investigated using multivariate analysis. Ninety-one migraine patients and 119 non-headache healthy volunteers were enrolled. The 12 gene polymorphisms analysis and NEO-FFI personality test were performed. At first, the univariate analysis was performed to extract the contributing factors to pathogenesis of migraine. We then extracted the factors that independently contributed to the pathogenesis of migraine using multivariate stepwise logistic regression analysis. Using the multivariate analysis, three gene polymorphisms including monoamine oxidase A (MAOA) T941G, methylenetetrahydrofolate reductase (MTHFR) C677T, and tumor necrosis factor beta (TNF-β) G252Α, and the neuroticism and conscientiousness scores in NEO-FFI were selected as significant factors that independently contributed to the pathogenesis of migraine. Their odds ratios were 1.099 (per point of neuroticism score), 1.080 (per point of conscientiousness score), 2.272 (T and T/T or T/G vs G and G/G genotype of MAOA), 1.939 (C/T or T/T vs C/C genotype of MTHFR), and 2.748 (G/A or A/A vs G/G genotype of TNF-β), respectively. We suggested that multiple factors, such as gene polymorphisms and personality traits, contribute to the pathogenesis of migraine. The contribution of polymorphisms, such as MAOA T941G, MTHFR C677T, and TNF-β G252A, were more important than personality traits in the pathogenesis of migraine, a multifactorial disorder.

  6. MTHFR 677C>T Polymorphism and the Risk of Breast Cancer: Evidence from an Original Study and Pooled Data for 28031 Cases and 31880 Controls

    PubMed Central

    Sekhar, Deepa; Francis, Amirtharaj; Gupta, Nishi; Konwar, Rituraj; Kumar, Sandeep; Kumar, Surender; Thangaraj, Kumarasamy; Rajender, Singh

    2015-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) acts at an important metabolic point in the regulation of cellular methylation reaction. It assists in the conversion of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. The latter aids in remethylation of homocysteine to de novo methionine that is required for DNA synthesis. The objective of this study was to examine the effect of MTHFR 677 C>T polymorphism on the risk of breast cancer in the Indian sub-continent. Methods and Results We genotyped 677 C>T locus in 1096 individuals that were classified into cases (N=588) and controls (N=508). Genotype data were analyzed using chi-square test. No significant difference was observed in the distribution of genotypes between cases and controls in north Indian (P = 0.932), south Indian (P = 0.865), and pooled data (P = 0.680). To develop a consensus regarding the impact of 677C>T polymorphism on breast cancer risk, we also conducted a meta-analysis on 28031 cases and 31880 controls that were pooled from sixty one studies. The overall summary estimate upon meta-analysis suggested no significant correlation between the 677C>T substitution and breast cancer in the dominant model (Fixed effect model: OR = 0.97, P=0.072, Random effects model: OR = 0.96, P = 0.084) or the recessive model (Fixed effect model: OR = 1.05, P = 0.089; Random effects model: OR= 1.08, P= 0.067). Conclusion 677 C>T substitution does not affect breast cancer risk in the Indo-European and Dravidian populations of India. Analysis on pooled data further ruled out association between the 677 C>T polymorphism and breast cancer. Therefore, 677 C>T substitution does not appear to influence the risk of breast cancer. PMID:25803740

  7. Homocysteine Metabolism Gene Polymorphisms (MTHFR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G) Jointly Elevate the Risk of Folate Deficiency.

    PubMed

    Li, Wen-Xing; Dai, Shao-Xing; Zheng, Jun-Juan; Liu, Jia-Qian; Huang, Jing-Fei

    2015-08-10

    Folate deficiency is strongly associated with cardiovascular disease. We aimed to explore the joint effect of the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, and methionine synthase reductase (MTRR) A66G polymorphisms on folate deficiency in a Chinese hypertensive population. A total of 480 subjects aged 28-75 were enrolled in this study from September 2005-December 2005 from six hospitals in different Chinese regions. Known genotypes were detected by PCR-RFLP methods and serum folate was measured by chemiluminescence immunoassay. Our results showed that MTHFR 677TT and MTR 2756AG + GG were independently associated with a higher risk of folate deficiency (TT vs. CC + CT, p < 0.001 and AG + GG vs. AA p = 0.030, respectively). However, the MTHFR A1298C mutation may confer protection by elevating the serum folate level (p = 0.025). Furthermore, patients carrying two or more risk genotypes showed higher odds of folate deficiency than null risk genotype carriers, especially those carrying four risk genotypes. These findings were verified by generalized multifactor dimensionality reduction (p = 0.0107) and a cumulative effects model (p = 0.001). The results of this study have shown that interactions among homocysteine metabolism gene polymorphisms lead to dramatic elevations in the folate deficiency risk.

  8. Association of polymorphisms in DNMT1, DNMT3A, DNMT3B, MTHFR and MTRR genes with global DNA methylation levels and prognosis of autoimmune thyroid disease.

    PubMed

    Arakawa, Y; Watanabe, M; Inoue, N; Sarumaru, M; Hidaka, Y; Iwatani, Y

    2012-11-01

    To clarify the association between factors regulating DNA methylation and the prognosis of autoimmune thyroid diseases (AITDs), we genotyped single nucleotide polymorphisms in genes encoding DNA methyltransferase 1 (DNMT1), DNMT3A, DNMT3B, methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR), which are enzymes essential for DNA methylation. Subjects for this study included 125 patients with Hashimoto's disease (HD), including 48 patients with severe HD and 49 patients with mild HD; 176 patients with Graves' disease (GD), including 79 patients with intractable GD and 47 patients with GD in remission; and 83 healthy volunteers (control subjects). The DNMT1+32204GG genotype was more frequent in patients with intractable GD than in patients with GD in remission. Genomic DNA showed significantly lower levels of global methylation in individuals with the DNMT1+32204GG genotype than in those with the AA genotype. The MTRR+66AA genotype was observed to be more frequent in patients with severe HD than in those with mild HD. The DNMT1+14395A/G, DNMT3B-579G/T, MTHFR+677C/T and +1298A/C polymorphisms were not correlated with the development or prognosis of AITD. Our study indicates that the DNMT1+32204GG genotype correlates with DNA hypomethylation and with the intractability of GD, and that the MTRR+66AA genotype may correlate with the severity of HD. © 2012 Osaka University. Clinical and Experimental Immunology © 2012 British Society for Immunology.

  9. Association of polymorphisms in DNMT1, DNMT3A, DNMT3B, MTHFR and MTRR genes with global DNA methylation levels and prognosis of autoimmune thyroid disease

    PubMed Central

    Arakawa, Y; Watanabe, M; Inoue, N; Sarumaru, M; Hidaka, Y; Iwatani, Y

    2012-01-01

    To clarify the association between factors regulating DNA methylation and the prognosis of autoimmune thyroid diseases (AITDs), we genotyped single nucleotide polymorphisms in genes encoding DNA methyltransferase 1 (DNMT1), DNMT3A, DNMT3B, methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR), which are enzymes essential for DNA methylation. Subjects for this study included 125 patients with Hashimoto's disease (HD), including 48 patients with severe HD and 49 patients with mild HD; 176 patients with Graves’ disease (GD), including 79 patients with intractable GD and 47 patients with GD in remission; and 83 healthy volunteers (control subjects). The DNMT1+32204GG genotype was more frequent in patients with intractable GD than in patients with GD in remission. Genomic DNA showed significantly lower levels of global methylation in individuals with the DNMT1+32204GG genotype than in those with the AA genotype. The MTRR+66AA genotype was observed to be more frequent in patients with severe HD than in those with mild HD. The DNMT1+14395A/G, DNMT3B−579G/T, MTHFR+677C/T and +1298A/C polymorphisms were not correlated with the development or prognosis of AITD. Our study indicates that the DNMT1+32204GG genotype correlates with DNA hypomethylation and with the intractability of GD, and that the MTRR+66AA genotype may correlate with the severity of HD. PMID:23039890

  10. Homocysteine Metabolism Gene Polymorphisms (MTHFR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G) Jointly Elevate the Risk of Folate Deficiency

    PubMed Central

    Li, Wen-Xing; Dai, Shao-Xing; Zheng, Jun-Juan; Liu, Jia-Qian; Huang, Jing-Fei

    2015-01-01

    Folate deficiency is strongly associated with cardiovascular disease. We aimed to explore the joint effect of the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, and methionine synthase reductase (MTRR) A66G polymorphisms on folate deficiency in a Chinese hypertensive population. A total of 480 subjects aged 28–75 were enrolled in this study from September 2005–December 2005 from six hospitals in different Chinese regions. Known genotypes were detected by PCR-RFLP methods and serum folate was measured by chemiluminescence immunoassay. Our results showed that MTHFR 677TT and MTR 2756AG + GG were independently associated with a higher risk of folate deficiency (TT vs. CC + CT, p < 0.001 and AG + GG vs. AA p = 0.030, respectively). However, the MTHFR A1298C mutation may confer protection by elevating the serum folate level (p = 0.025). Furthermore, patients carrying two or more risk genotypes showed higher odds of folate deficiency than null risk genotype carriers, especially those carrying four risk genotypes. These findings were verified by generalized multifactor dimensionality reduction (p = 0.0107) and a cumulative effects model (p = 0.001). The results of this study have shown that interactions among homocysteine metabolism gene polymorphisms lead to dramatic elevations in the folate deficiency risk. PMID:26266420

  11. The effects of genomic polymorphisms in one-carbon metabolism pathways on survival of gastric cancer patients received fluorouracil-based adjuvant therapy

    PubMed Central

    Zhao, Tingting; Xu, Zhi; Gu, Dongying; Wu, Peng; Huo, Xinying; Wei, Xiaowei; Tang, Yongfei; Gong, Weida; He, Ming-Liang; Chen, Jinfei

    2016-01-01

    5-fluorouracil (5-FU) is widely used to treat patients with gastric cancer (GC). However, the response rate is quite heterogeneous. The single nucleotide polymorphisms (SNPs) and their interactions of genes in the one-carbon metabolism (OCM) pathway, including Methylenetetrahydrofolate reductase (MTHFR), Methionine synthase reductase (MTRR), Methionine synthase (MTR), and Thymidylate synthase (TS), significantly affect 5-FU metabolism. In this study, 650 stage II-III patients were recruited from 1998 to 2006. Among them, 251 received 5-FU treatment and other 399 patients were untreated. The Cox regression analysis, log-rank tests and Kaplan–Meier plots were adopted. In the chemotherapy cohort, MTRR 66 GA + GG genotypes decreased death risk, however, the protect effect of MTRR 66 GA + GG disappeared when GC patients simultaneously had MTHFR 677TT + TC or MTR 2756GG + GA genotypes. TS 5′-UTR 2R3R + 3R3R genotypes also prolonged overall survival of patients treated with 5-FU. And this favorable prognosis obviously enhanced when GC patients simultaneously had TS 3′-UTR DD + DI and TS 5′-UTR 2R3R + 3R3R genotypes. Our findings showed that the polymorphisms of MTRR 66 A > G and TS 5′-UTR 3R > 2R may be potential prognostic factors for GC patients receiving 5-FU. PMID:27456431

  12. The 844ins68 cystathionine beta-synthase and C677T MTHFR gene polymorphism and the vaso-occlusive event risk in sickle cell disease

    PubMed Central

    Alves Jacob, Maza; da Cunha Bastos, Celso; Regina Bonini-Domingos, Claudia

    2011-01-01

    Introduction Sickle cell disease (SCD) is an inflammatory condition with an increase in the adhesion of sickled erythrocytes, and it is a potential cause of vaso-occlusive episodes, an event related to clinical manifestations, morbidity and mortality. The cystathionine beta-synthase enzyme gene (CBS) and the methylenetetrahydrofolate reductase enzyme gene (MTHFR) are risk factors for thromboembolic disorders. This study evaluated the frequency of the 844ins68 CBS and C677T MTHFR gene polymorphisms and their possibility to be risk factors for vaso-occlusive crises. Material and methods In total 91 blood samples from SCD patients were studied by PCR-RFLP and PCR-allele-specific, for the SCD genotype confirmation and polymorphism identification. Results The presence of clinical manifestations related to vaso-occlusive crises were more frequent among patients with the Hb SS genotype (p = 0.007). The CBS enzyme gene was three times more frequent (p = 0.011) among patients with vaso-occlusive complications. The MTHFR gene mutation frequency showed no increased risk for vaso-occlusive crises in SCD patients (p = 0.193). The interaction between the two polymorphisms was evaluated in 12.08% of the SCD patients and doubled the vaso-occlusive disease risk (relative risk: 2.16). Conclusions We conclude that the presence of 844ins68 CBS and C677T MTHFR gene polymorphism was a risk factor for vaso-occlusive episodes in the SCD patients evaluated. PMID:22291740

  13. Homocysteine and the C677T Gene Polymorphism of Its Key Metabolic Enzyme MTHFR Are Risk Factors of Early Renal Damage in Hypertension in a Chinese Han Population

    PubMed Central

    Yun, Lin; Xu, Rui; Li, Guohua; Yao, Yucai; Li, Jiamin; Cong, Dehong; Xu, Xingshun; Zhang, Lihua

    2015-01-01

    Abstract The combined hyperhomocysteinemia condition is a feature of the Chinese hypertensive population. This study used the case-control method to investigate the association between plasma homocysteine and the C677T gene polymorphism of its key metabolic enzyme, 5, 10-methylenetetrahydrofolate reductase (MTHFR), and early renal damage in a hypertensive Chinese Han population. A total of 379 adult essential hypertensive patients were selected as the study subjects. The personal information, clinical indicators, and the C677T gene polymorphism of MTHFR were texted. This study used the urine microalbumin/urine creatinine ratio (UACR) as a grouping basis: the hypertension without renal damage group (NRD group) and the hypertension combined with early renal damage group (ERD group). Early renal damage in the Chinese hypertensive population was associated with body weight, systolic pressure, diastolic pressure, urea nitrogen, serum creatinine, cystatin C, uric acid, aldosterone, and glomerular filtration rate. The homocysteine level and the UACR in the TT genotype group were higher than those in the CC genotype group. The binary logistic regression analysis results showed that after sex and age were adjusted, the MTHFR C677T gene polymorphism was correlated with early renal damage in hypertension in both the recessive model and in the additive model. Plasma homocysteine and the C677T gene polymorphism of its key metabolic enzyme MTHFR might be independent risk factors of early renal damage in the hypertensive Chinese Han population. PMID:26717388

  14. Association between MTHFR C677T Polymorphism and Risk of Acute Lymphoblastic Leukemia: A Meta-Analysis Based on 51 Case-Control Studies

    PubMed Central

    Li, Su-yi; Ye, Jie-yu; Liang, En-yu; Zhou, Li-xia; Yang, Mo

    2015-01-01

    Background Studies and systematic reviews have reached inconsistent conclusions on the role of 5, 10-methylenetetrahydrofolate reductase (MTHFR) polymorphism C677T in acute lymphoblastic leukemia (ALL) risk. Material/Methods The present meta-analysis comprising of 51 case-control studies, including 7892 cases and 14 280 controls was performed to reevaluate the association between MTHFR C677T polymorphism and ALL risk. Results Statistical differences were found in the dominant model (TT+CT vs. CC, odd ratio (OR)=0.89, 95% CI, 0.79–1.00, P=0.04) and the CT vs. CC (OR=0.89, 95% CI, 0.80–1.00, P=0.05), but not in the allele contrast model (T vs. C, OR=0.92, 95% CI, 0.84–1.01, P=0.08), additive model (TT vs. CC, OR=0.87, 95% CI, 0.73–1.05, P=0.15), or recessive model (TT vs. CT+CC, OR=0.94, 95% CI, 0.81–1.10, P=0.44) in overall populations. In the subgroup analyses stratified by age (children and adults) and ethnicity (Asian and Caucasian), no significant associations between MTHFR C677T polymorphism and ALL risk were observed. Conclusions The current study found no sufficient evidence of a protective role of MTHFR C677T polymorphism in ALL susceptibility. PMID:25761797

  15. Screening of polymorphisms for MTHFR and DHFR genes in spina bifida children and their mothers

    NASA Astrophysics Data System (ADS)

    Husna, M. Z.; Endom, I.; Ibrahim, S.; Selvi, N. Amaramalar; Fakhrurazi, H.; Htwe, R. Ohnmar; Kanehaswari, Y.; Halim, A. R. Abdul; Wong, S. W.; Subashini, K.; Syahira, O. Nur; Aishah, S.

    2013-11-01

    Mechanism underlying the beneficial effect of folic acid supplementation in reducing the risk of neural tube defect is still not well understood. Current evidences show the involvement of folic acid metabolic gene's polymorphism as contributing factors that regulate this pathway. Therefore, the objective of this research was to determine the presence of C677T polymorphism for methylenetetrahydrofolate reductase (MTHFR) and dihydrofolate reductase (DHFR-19 bp deletion) genes between mother-children pairs of case and control. With the approval of UKMMC ethic committee, genomic DNA was extracted from one hundred and forty consented bloods. Polymerase chain reaction (PCR), PCR-RFLP (Restriction Fragment Length Polymorphism) and sequencing were employed to verify each nucleotide change. Our result shows that mutant MTHFR and DHFR alleles are present in all Malaysian sub-ethnic groups, case and control. Even though mutant MTHFR are found to be slightly higher in the case groups, 75% of the affected child is a non carrier for this allele and 62.5% of the mothers with an affected child are genotypically normal. For DHFR, almost all (87.5-100%) investigated samples are a carrier or having a double DHFR deletion be it a case or control pairs. However, strong maternal inheritance shown by the deleted allele might be due to a cascade effect of lacks of folate consumption or maternal uniparental disomy. In conclusion, the use of MTHFR and DHFR as markers in determining the risk of having spina bifida baby is uninformative and plays a small indirect role as the genetic causes of spina bifida. Therefore, spina bifida remains etiologically unknown polygenic and quantitative developmental trait whereby the searches for positive genetic marker need to be continued.

  16. Gene polymorphisms in folate metabolizing enzymes in adult acute lymphoblastic leukemia: effects on methotrexate-related toxicity and survival

    PubMed Central

    Ongaro, Alessia; De Mattei, Monica; Della Porta, Matteo Giovanni; Rigolin, GianMatteo; Ambrosio, Cristina; Di Raimondo, Francesco; Pellati, Agnese; Masieri, Federica Francesca; Caruso, Angelo; Catozzi, Linda; Gemmati, Donato

    2009-01-01

    Background The antifolate agent methotrexate is an important component of maintenance therapy in acute lymphoblastic leukemia, although methotrexate-related toxicity is often a reason for interruption of chemotherapy. Prediction of toxicity is difficult because of inter-individual variability susceptibility to antileukemic agents. Methotrexate interferes with folate metabolism leading to depletion of reduced folates. Design and Methods The aim of this study was to investigate the influence of polymorphisms for folate metabolizing enzymes with respect to toxicity and survival in adult patients with acute lymphoblastic leukemia treated with methotrexate maintenance therapy. To this purpose, we evaluated possible associations between genotype and hematologic and non-hematologic toxicity and effects on survival at 2 years of follow-up in patients with acute lymphoblastic leukemia. Results Polymorphisms in the genes encoding for methylenetetrahydrofolate reductase (MTHFR 677C>T) and in dihydrofolate reductase (DHFR 19 bp deletion) significantly increased the risk of hepatotoxicity in single (odds ratio 5.23, 95% confidence interval 1.13–21.95 and odds ratio 4.57, 95% confidence interval 1.01–20.77, respectively) and in combined analysis (odds ratio 6.82, 95% confidence interval 1.38–33.59). MTHFR 677C>T also increased the risk of leukopenia and gastrointestinal toxicity, whilst thymidylate synthase 28 bp repeat polymorphism increased the risk of anemia (odds ratio 8.48, 95% confidence interval 2.00–36.09). Finally, patients with MTHFR 677TT had a decreased overall survival rate (hazard ratio 2.37, 95% confidence interval 1.46–8.45). Conclusions Genotyping of folate polymorphisms might be useful in adult acute lymphoblastic leukemia to optimize methotrexate therapy, reducing the associated toxicity with possible effects on survival. PMID:19648163

  17. Cytochrome P450 (CYP2C9*2,*3) & vitamin-K epoxide reductase complex (VKORC1 -1639Gpolymorphisms & their effect on acenocoumarol dose in patients with mechanical heart valve replacement

    PubMed Central

    Kaur, Anupriya; Khan, Farah; Agrawal, Suraksha S.; Kapoor, Aditya; Agarwal, Surendra K.; Phadke, Shubha R.

    2013-01-01

    Background & objectives: Studies have demonstrated the effect of CYP2C9 (cytochrome P450) and VKORC1 (vitamin K epoxide reductase complex) gene polymorphisms on the dose of acenocoumarol. The data from India about these gene polymorphisms and their effects on acenocoumarol dose are scarce. The aim of this study was to determine the occurrence of CYP2C9*2,*3 and VKORC 1 -1639G>A gene polymorphisms and to study their effects on the dose of acenocoumarol required to maintain a target International Normalized Ratio (INR) in patients with mechanical heart valve replacement. Methods: Patients from the anticoagulation clinic of a tertiary care hospital in north India were studied. The anticoagulation profile, INR (International Normalized Ratio) values and administered acenocoumarol dose were obtained from the clinical records of patients. Determination of the CYP2C9*2,*3 and VKORC1 -1639G>A genotypes was done by PCR-RFLP (restriction fragment length polymorphism). Results: A total of 111 patients were studied. The genotype frequencies of CYP2C9 *1/*1,*1/*2,*1/*3 were as 0.883, 0.072, 0.036 and that of VKORC1 -1639G>A for GG, AG, and AA genotypes were 0.883, 0.090, and 0.027, respectively. The percentage of patients carrying any of the variant alleles of CYP2C9 and VKORC1 in heterozygous or homozygous form was 34% among those receiving a low dose of ≤20 mg/wk while it was 13.8 per cent in those receiving >20 mg/wk (P=0.014). A tendency of lower dose requirements was seen among carriers of the studied polymorphisms. There was considerable variability in the dose requirements of patients with and without variant alleles. Interpretation & conclusions: The study findings point towards the role of CYP2C9 and VKORC1 gene polymorphisms in determining the inter-individual dose variability of acenocoumarol in the Indian patients with mechanical heart valve replacement. PMID:23481074

  18. Analysis of MTHFR and MTRR Gene Polymorphisms in Iranian Ventricular Septal Defect Subjects

    PubMed Central

    Pishva, Seyyed Reza; Vasudevan, Ramachandran; Etemad, Ali; Heidari, Farzad; Komara, Makanko; Ismail, Patimah; Othman, Fauziah; Karimi, Abdollah; Sabri, Mohammad Reza

    2013-01-01

    Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects. PMID:23358257

  19. Analysis of MTHFR and MTRR Gene Polymorphisms in Iranian Ventricular Septal Defect Subjects.

    PubMed

    Pishva, Seyyed Reza; Vasudevan, Ramachandran; Etemad, Ali; Heidari, Farzad; Komara, Makanko; Ismail, Patimah; Othman, Fauziah; Karimi, Abdollah; Sabri, Mohammad Reza

    2013-01-28

    Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects.

  20. Thioredoxin reductase.

    PubMed Central

    Mustacich, D; Powis, G

    2000-01-01

    The mammalian thioredoxin reductases (TrxRs) are a family of selenium-containing pyridine nucleotide-disulphide oxidoreductases with mechanistic and sequence identity, including a conserved -Cys-Val-Asn-Val-Gly-Cys- redox catalytic site, to glutathione reductases. TrxRs catalyse the NADPH-dependent reduction of the redox protein thioredoxin (Trx), as well as of other endogenous and exogenous compounds. The broad substrate specificity of mammalian TrxRs is due to a second redox-active site, a C-terminal -Cys-SeCys- (where SeCys is selenocysteine), that is not found in glutathione reductase or Escherichia coli TrxR. There are currently two confirmed forms of mammalian TrxRs, TrxR1 and TrxR2, and it is possible that other forms will be identified. The availability of Se is a key factor determining TrxR activity both in cell culture and in vivo, and the mechanism(s) for the incorporation of Se into TrxRs, as well as the regulation of TrxR activity, have only recently begun to be investigated. The importance of Trx to many aspects of cell function make it likely that TrxRs also play a role in protection against oxidant injury, cell growth and transformation, and the recycling of ascorbate from its oxidized form. Since TrxRs are able to reduce a number of substrates other than Trx, it is likely that additional biological effects will be discovered for TrxR. Furthermore, inhibiting TrxR with drugs may lead to new treatments for human diseases such as cancer, AIDS and autoimmune diseases. PMID:10657232

  1. Triplex tetra-primer ARMS-PCR method for the simultaneous detection of MTHFR c.677C>T and c.1298A>C, and MTRR c.66A>G polymorphisms of the folate-homocysteine metabolic pathway.

    PubMed

    Lajin, Bassam; Alachkar, Amal; Sakur, Amir Alhaj

    2012-02-01

    The folate-homocysteine metabolic pathway was shown to play an important role in several diseases such as cancers, cardiovascular diseases, and neurodegenerative diseases. The c.677C>T and c.1298A>C polymorphisms of the Methylenetetrahydrofolate reductase (MTHFR) gene, and c.66A>G of the Methionine synthase reductase (MTRR) gene are the most commonly investigated polymorphisms in the folate-homocysteine metabolic pathway. The currently used methods for the detection of the three polymorphisms are either slow and laborious or extremely expensive. In this paper, a new highly optimized method for the simultaneous detection of the three single nucleotide polymorphisms is described. The proposed method utilizes 12 primers in a single PCR reaction to detect the three polymorphisms simultaneously based on the principle of tetra-primer ARMS-PCR (also known as PCR-CTPP). The proposed method offers extremely fast, economical, and simple detection. Validation by PCR-RFLP showed 100% concordance in genotype assignment. The proposed method was successfully applied to a sample of the Syrian population (n=126), which was not previously genotyped for any of the three SNPs. The variant allele frequencies were found to be 31, 29, and 43% for the c.677C>T, c.1298A>C, and c.66A>G polymorphisms, respectively. The proposed method is the first to detect three SNPs in a single PCR reaction based on tetra-primer ARMS-PCR or PCR-CTPP. We suggest that the use of Betaine may play an important role in multiplex tetra-primer ARMS-PCR or PCR-CTPP based on its potential capacity to close the gap in melting temperature between different primers. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Folate and One-Carbon Metabolism Gene Polymorphisms and Their Associations With Oral Facial Clefts

    PubMed Central

    Boyles, Abee L.; Wilcox, Allen J.; Taylor, Jack A.; Meyer, Klaus; Fredriksen, Åse; Ueland, Per Magne; Drevon, Christian A.; Vollset, Stein Emil; Lie, Rolv Terje

    2008-01-01

    Folate metabolism plays a critical role in embryonic development. Prenatal folate supplementation reduces the risk of neural tube defects and probably oral facial clefts. Previous studies of related metabolic genes have associated polymorphisms in cystathionine-beta-synthase (CBS) and 5,10-methylenetetrahydrofolate reductase (MTHFR) with cleft risk. We explored associations between genes related to one-carbon metabolism and clefts in a Norwegian population-based study that included 362 families with cleft lip with or without cleft palate (CL/P) and 191 families with cleft palate only (CPO). We previously showed a 39% reduction in risk of CL/P with folic acid supplementation in this population. In the present study we genotyped 12 polymorphisms in nine genes related to one-carbon metabolism and looked for associations of clefting risk with fetal polymorphisms, maternal polymorphisms, as well as parent-of-origin effects, using combined likelihood-ratio tests (LRT). We also stratified by maternal periconceptional intake of folic acid (>400 μg) to explore gene-exposure interactions. We found a reduced risk of CL/P with mothers who carried the CBS C699T variant (rs234706); relative risk was 0.94 with one copy of the T allele (95% CI 0.63-1.4) and 0.50 (95% CI 0.26-0.96) with two copies (P = 0.008). We found no evidence of interaction of this variant with folate status. We saw no evidence of risk from the MTHFR C677T variant (rs1801133) either overall or after stratifying by maternal folate intake. No associations were found between any of the polymorphisms and CPO. Genetic variations in the nine metabolic genes examined here do not confer a substantial degree of risk for clefts. Published 2008 Wiley-Liss, Inc.† PMID:18203168

  3. Polymorphisms in folate and homocysteine metabolizing genes and chromosome damage in mothers of Down syndrome children.

    PubMed

    Coppedè, Fabio; Colognato, Renato; Bonelli, Alessia; Astrea, Guja; Bargagna, Stefania; Siciliano, Gabriele; Migliore, Lucia

    2007-09-01

    We recently observed an association between combinations of polymorphisms in the methylenetetrahydrofolate reductase (MTHFR 677C > T or 1298A > C) and reduced folate carrier (RFC-1 80G > A) genes and the risk of a Down syndrome (DS) pregnancy in young Italian women. Others have observed an association between a methionine synthase (MTR 2756A > G) gene polymorphism and the risk of a DS offspring in Italy. Moreover, in a separate study, we observed an increased frequency of both binucleated micronucleated cells (BNMN) and chromosome malsegregation events in peripheral lymphocytes of mothers of DS individuals aged less than 35 years at conception (MDS) in respect to controls. The aim of the present study was to evaluate chromosome damage, measured by means of the micronucleus assay, in peripheral lymphocytes of a group of women (n = 34) who had a DS child in young age (<35 years) and in a control group (n = 35), and to correlate them with MTHFR 677C > T and 1298A > C, RFC-1 80G > A and MTR 2756A > G polymorphisms. We observed an increased frequency of BNMN in the MDS group compared to the control group (17.13 +/- 8.31 per thousand vs. 10.28 +/- 4.53 per thousand; P < 0.001), and, in the general population, a correlation between years of age and BNMN frequency (P = 0.05). A significant correlation between the frequency of BNMN and the MTHFR 677C > T polymorphism (P = 0.038) was also found. Present results indicate that MDS are more prone to chromosome damage than control mothers; moreover the contribution of folate and homocysteine metabolizing gene polymorphisms seems to have an effect on the baseline frequency of BNMN lymphocytes. Copyright 2007 Wiley-Liss, Inc.

  4. Association between MTHFR A1298C polymorphism and male infertility: A meta-analysis.

    PubMed

    Zhang, Qiang; Yin, Guo-Ying; Liu, Juan; Liang, Yue; Li, Yao-Yan; Zhao, Jing-Yu; Zhang, Li-Wen; Wang, Bai-Qi; Tang, Nai-Jun

    2017-04-01

    There have been several epidemiological studies evaluating the potential association between the methylenetetrahydrofolate reductase (MTHFR) A1298C polymorphism and the risk of male infertility. However, the results obtained were inconsistent. Therefore, we performed a meta-analysis to further examine the association between the MTHFR A1298C polymorphism and male infertility. A comprehensive search was conducted to identify all eligible studies from the online literature databases published prior to January 15th, 2016. A total of 20 studies with 4293 cases and 4507 controls were included. An odds ratio (OR) and a 95% confidence interval (95% CI) were calculated to assess the strength of the association. A cumulative meta-analysis, sensitivity analysis and assessment of the publication bias were also performed in this study. The results showed that in the overall analysis, the association between the MTHFR A1298C polymorphism and male infertility was not significant. A stratified analysis by ethnicity revealed a significant increase in the risk of male infertility in the Asian population with the MTHFR A1298C polymorphism (especially in the heterozygote model: OR=1.20, 95% CI=1.01-1.44, P=0.994; the dominant model: OR=1.23, 95% CI=1.04-1.45, P=0.996; and the allele model: OR=1.20, 95% CI=1.04-1.39, P=0.985) but not in the Caucasian population. In the stratified analyses, no significant association was observed between the different types of male infertility. This meta-analysis suggests the MTHFR A1298C polymorphism may be a potential risk factor for male infertility, especially in the Asian population.

  5. Meta-analysis of the association of MTHFR polymorphisms with multiple myeloma risk

    PubMed Central

    Ma, Li-Min; Ruan, Lin-Hai; Yang, Hai-Ping

    2015-01-01

    The association of methylenetetrahydrofolate reductase (MTHFR) polymorphisms with multiple myeloma (MM) risk has been explored, but the results remain controversial. Thus, a meta-analysis was performed to provide a comprehensively estimate. The case-control studies about MTHFR C677T and A1298C polymorphisms with MM risk were collected by searching PubMed, Elsevier, China National Knowledge Infrastructure and Wanfang Databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the strength of association. Overall, no significant association was found between MTHFR A1298C polymorphism and MM risk under all four genetic models (AC vs. AA, OR = 0.99, 95%CI = 0.82-1.20; CC vs. AA, OR = 1.14, 95%CI = 0.77-1.68; recessive model, OR = 1.10, 95%CI = 0.76-1.59; dominant model, OR = 1.01, 95%CI = 0.84-1.22). The risk was also not significantly altered for C677T polymorphism and MM in overall comparisons (CT vs. CC, OR = 1.04, 95%CI = 0.93-1.17; TT vs. CC, OR = 1.16, 95%CI = 0.98-1.37; recessive model, OR = 1.13, 95%CI = 0.98-1.32; dominant model, OR = 1.07, 95%CI = 0.96-1.20). In subgroup analyses by ethnicity, no significant association was observed in both Caucasians and Asians. This meta-analysis suggested that MTHFR polymorphisms were not associated with MM risk. PMID:26022785

  6. Functional Polymorphism rs13306560 of the MTHFR Gene Is Associated With Essential Hypertension in a Mexican-Mestizo Population.

    PubMed

    Pérez-Razo, Juan Carlos; Cano-Martínez, Luis Javier; Vargas Alarcón, Gilberto; Canizales-Quinteros, Samuel; Martínez-Rodríguez, Nancy; Canto, Patricia; Roque-Ramírez, Bladimir; Palma-Flores, Carlos; Esteban-Martínez, Rosa; López-Hernández, Luz Berenice; Rojano-Mejía, David; Coral-Vázquez, Ramón M

    2015-08-01

    Polymorphisms of methylenetetrahydrofolate reductase (MTHFR) have been associated with diastolic blood pressure, hypertension, and other cardiovascular diseases; however, results of these studies are still controversial. In this study, we sought to determine whether 2 functional variants (rs1801133 and rs13306560) within the MTHFR are associated with hypertension in Mexican-Mestizos. We performed a case-control study with 1214 subjects including adults and children to test for the association of both single nucleotide polymorphisms with essential hypertension. The adult group included 764 participants (372 patients and 391 controls) and the group of children included 418 participants (209 patients and 209 controls). rs13306560 was associated with essential hypertension in adults (odds ratio, 4.281; 95% confidence interval, 1.841-9.955; P=0.0003) with a statistical power >0.8. In children, none of the polymorphisms was associated with essential hypertension. In addition, we assessed the effect of the rs13306560 polymorphism on the MTHFR promoter region by means of luciferase reporter gene assays using human umbilical vein endothelial cells. Cells transfected with the pMTHFRaLUC construct showed an ≈25% reduction in luciferase activity (P=0.003). Furthermore, the promoter activity was reduced considerably by in vitro methylation of CpG sequences. Our data suggest that the rs13306560 polymorphism of the MTHFR may be part of the observed hypertension process in Mexican-Mestizo populations, but further studies are warranted. In addition, the allele A of the rs13306560 polymorphism as well as the in vitro methylation of CpGs reduced the promoter activity of the MTHFR regulatory region. © 2015 American Heart Association, Inc.

  7. MTHFR 677C>T Polymorphism Increases the Male Infertility Risk: A Meta-Analysis Involving 26 Studies

    PubMed Central

    Gong, Mancheng; Dong, Wenjing; He, Tingyu; Shi, Zhirong; Huang, Guiying; Ren, Rui; Huang, Sichong; Qiu, Shaopeng; Yuan, Runqiang

    2015-01-01

    Background and Objectives Methylenetetrahydrofolate reductase (MTHFR) polymorphism may be a risk factor for male infertility. However, the epidemiologic studies showed inconsistent results regarding MTHFR polymorphism and the risk of male infertility. Therefore, we performed a meta-analysis of published case-control studies to re-examine the controversy. Methods Electronic searches of PubMed, EMBASE, Google Scholar and China National Knowledge Infrastructure (CNKI) were conducted to select eligible literatures for this meta-analysis (updated to June 19, 2014). According to our inclusion criteria and the Newcastle-Ottawa Scale (NOS), only high quality studies that observed the association between MTHFR polymorphism and male infertility risk were included. Crude odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of association between the MTHFR polymorphism and male infertility risk. Results Twenty-six studies involving 5,575 cases and 5,447 controls were recruited. Overall, MTHFR 677C>T polymorphism showed significant associations with male infertility risk in both fixed effects (CT+TT vs. CC: OR = 1.34, 95% CI: 1.23–1.46) and random effects models (CT+TT vs. CC: OR = 1.39, 95% CI: 1.19–1.62). Further, when stratified by ethnicity, sperm concentration and control sources, the similar results were observed in Asians, Caucasians, Azoo or OAT subgroup and both in population-based and hospital-based controls. Nevertheless, no significant association was only observed in oligo subgroup. Conclusions Our results indicated that the MTHFR polymorphism is associated with an increased risk of male infertility. Further well-designed analytical studies are necessary to confirm our conclusions and evaluate gene-environment interactions with male infertility risk. PMID:25793386

  8. Clinical Relevance of MTHFR, eNOS, ACE, and ApoE Gene Polymorphisms and Serum Vitamin Profile among Malay Patients with Ischemic Stroke.

    PubMed

    Wei, Loo Keat; Au, Anthony; Menon, Saras; Gan, Siew Hua; Griffiths, Lyn R

    2015-09-01

    The purpose of this study was threefold. First, it was to determine the relationship between serum vitamin profiles and ischemic stroke. The second purpose was to investigate the association of methylenetetrahydrofolate reductase (MTHFR), endothelial nitric oxide synthase (eNOS), angiotensin converting enzyme (ACE), and apolipoprotein-E (ApoE) gene polymorphisms with ischemic stroke and further correlate with serum vitamin profiles among ischemic stroke patients. The third purpose of the study was to highlight the interaction of MTHFR and eNOS haplotypes with serum vitamin profiles and ischemic stroke risks. Polymorphisms of these genes were analyzed in age-, sex-, and ethnicity-matched case-controls (n = 594); serum vitamin profiles were determined using immunoassays. The MTHFR 677C>T, 1298A>C, eNOS intron 4a/b, and ApoE polymorphisms were significantly associated with the increased risk of ischemic stroke. Elevated serum homocysteine and vitamin B12 levels were associated with MTHFR 677C>T and eNOS intron 4a/b polymorphisms. The ApoE and eNOS -786T>C polymorphisms were associated with increased serum vitamin B12 levels. However, none of the polymorphisms influenced serum folate levels except for the MTHFR 1298A>C. Different patterns of MTHFR and eNOS haplotypes tend to affect serum vitamin profiles to different degrees, which contribute to either different susceptibility risk or protective effect on ischemic stroke. Overall, increased levels of serum homocysteine and vitamin B12 levels were associated with higher risk of ischemic stroke in the investigated population. The present study suggests that the genotypes and haplotypes of MTHFR 677C>T and eNOS intron 4a/b polymorphisms are potential serum biomarkers in the pathophysiological processes of ischemic stroke, by modulating homocysteine and vitamin B12 levels. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  9. Interaction of MTHFR C677T and A1298C, and MTR A2756G gene polymorphisms in breast cancer risk in a population in Northeast Brazil.

    PubMed

    de Cássia Carvalho Barbosa, Rita; da Costa, Débora Menezes; Cordeiro, Denise Ellen Francelino; Vieira, Ana Patricia Freitas; Rabenhorst, Silvia Helena Barem

    2012-11-01

    Polymorphisms in genes encoding enzymes of folate metabolism are a focus of breast cancer risk studies due of the role of these enzymes in DNA methylation, synthesis, and repair. MTHFR, encoding for 5,10-methylenetetrahydrofolate reductase, is one of the most studied genes in this regard, but findings are controversial, and the majority of studies have analyzed polymorphisms individually. In this case control study, we examined the combination of the polymorphisms MTHFR C677T and A1298C with MTR A2756G, where MTR, methionine synthase, is an important enzyme of the folate cycle in the methylation pathway. One hundred and forty-two patients with breast cancer and controls were included and the genotypes were determined using PCR-RFLP. In the population studied, individuals carrying the polymorphic allele in the heterozygous state for both enzymes, MTHFR C677T and MTR A2756G, had an increased risk [odds ratio, OR=2.77 (95% confidence interval, CI=1.19-6.52)] for disease, compared to those with the wild genotype. In addition, individuals carrying the MTR 2756 genotype AG had an increased risk when this was combined with the MTHFR 1298 genotype CC [OR=5.13 (95% CI=0.87-38.82)]. No significant results were found from the analyses associating the MTHFR C677T and A1298C genotypes. However, when stratifying the patients by age (50 years old as the cut-off), patients over 50 years old had greater risk, with the presence of both MTHFR polymorphisms in the heterozygous state [OR=5.33 (95% CI=1.42-21.03)]. This study points out the importance of the interactions between the MTHFR C677T, MTHFR A1298C and MTR A2756G polymorphisms, and also highlights the relevance of the MTR A2756G polymorphism and age in breast cancer risk.

  10. Association of Polymorphisms in BDNF, MTHFR, and Genes Involved in the Dopaminergic Pathway with Memory in a Healthy Chinese Population

    ERIC Educational Resources Information Center

    Yeh, Ting-Kuang; Hu, Chung-Yi; Yeh, Ting-Chi; Lin, Pei-Jung; Wu, Chung-Hsin; Lee, Po-Lei; Chang, Chun-Yen

    2012-01-01

    The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single…

  11. Association of Polymorphisms in BDNF, MTHFR, and Genes Involved in the Dopaminergic Pathway with Memory in a Healthy Chinese Population

    ERIC Educational Resources Information Center

    Yeh, Ting-Kuang; Hu, Chung-Yi; Yeh, Ting-Chi; Lin, Pei-Jung; Wu, Chung-Hsin; Lee, Po-Lei; Chang, Chun-Yen

    2012-01-01

    The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single…

  12. MTHFR C677T polymorphism, homocysteine and B-vitamins status in a sample of Chinese and Malay subjects in Universiti Putra Malaysia.

    PubMed

    Choo, S C; Loh, S P; Khor, G L; Sabariah, M N; Rozita, R

    2011-08-01

    Methylenetetrahydrofolate reductase (MTHFR) C677T is involved in folate and homocysteine metabolism. Disruption in the activity of this enzyme will alter their levels in the body. This study assessed MTHFR C677T polymorphism and its relationship with serum homocysteine and B-vitamins levels in a sample of Chinese and Malays subjects in UPM, Serdang. One hundred subjects were randomly selected from among the university population. Folate, vitamin B12, B6, and homocysteine levels were determined using MBA, ECLIA, and HPLC, respectively. PCR coupled with HinfI digestion was used for detection of MTHFR C677T polymorphism. The frequency of T allele was higher in the Chinese subjects (0.40) compared to the Malay (0.14). Folate, vitamin B12 and B6 levels were highest in the wild genotype in both ethnic groups. Subjects with heterozygous and homozygous genotype showed the highest homocysteine levels. The serum folate and homocysteine were mainly affected by homozygous genotype. MTHFR C677T polymorphism plays an important role in influencing the folate and homocysteine metabolism.

  13. Maternal gene polymorphisms involved in folate metabolism and the risk of having a Down syndrome offspring: a meta-analysis.

    PubMed

    Yang, Mei; Gong, Tian; Lin, Xiaofang; Qi, Ling; Guo, Yiyang; Cao, Zhongqiang; Shen, Min; Du, Yukai

    2013-11-01

    Down syndrome (DS) is the most common chromosomal abnormality. Many studies have assessed the association between maternal gene polymorphisms involved in folate metabolism and the risk of having a DS offspring, but data are conflicting. Our study aimed to arrive at a more accurate estimation. Therefore, we carried out a meta-analysis of 26, 17, 9, 15, 9 and 6 case-control studies on the relationship between maternal methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, methionine synthase reductase (MTRR) A66G, reduced folate carrier 1 A80G and cystathionine β-synthase 844ins68 polymorphisms and the risk of having a DS offspring. The allele contrast and model-free approach were used. Results showed marginal significant associations for MTHFR C677T, overall [odds ratio (OR) = 1.28 (1.22, 1.46) and generalised odds ratio (ORG) = 1.35 (1.16, 1.57)] and in Caucasian [OR = 1.15 (1.03, 1.29) and ORG = 1.20 (1.04, 1.38)], Asian [OR = 1.68 (1.08, 2.63) and ORG = 1.74 (1.08, 2.80)] and Brazilian [OR = 1.22 (1.04, 1.43) and ORG = 1.28 (1.06, 1.55)] populations; for MTRR A66G, overall [OR = 1.22 (1.02, 1.46) and ORG = 1.31 (1.06, 1.62)]; and for RFC1 A80G, overall [OR = 1.16 (1.02, 1.31) and ORG = 1.18 (1.01, 1.37)]. MTHFR A1298C, MTR 12756G and CBS 844ins68 polymorphisms produced non-significant results. Since potential confounders could not be ruled out completely in this meta-analysis, further studies are needed to confirm these results.

  14. Geographical and Ethnic Distributions of the MTHFR C677T, A1298C and MTRR A66G Gene Polymorphisms in Chinese Populations: A Meta-Analysis

    PubMed Central

    Zeng, Dingyuan

    2016-01-01

    Background The geographical and ethnic distributions of the polymorphic methylenetetrahydrofolate reductase (MTHFR) mutations (C677T and A1298C) and methionine synthase reductase (MTRR) mutation (A66G) remain heterogeneous in China. The goal of this study was to estimate the pooled frequencies of the alleles and associated genotypes of these gene polymorphisms among healthy populations in Mainland China. Objective and Methods We systematically reviewed published epidemiological studies on the distributions of 3 genetic variants in Chinese healthy populations living in Mainland China through a meta-analysis. The relevant electronic databases were searched. All of the raw data of the eligible citations were extracted. The frequency estimates were stratified by geography, ethnicity and sex. Results Sixty-six studies were identified with a total of 92277 study participants. The meta-analysis revealed that the frequencies of the MTHFR C677T, A1298C, and MTRR A66G gene polymorphisms varied significantly between different ethnic groups and along geographical gradients. The frequencies of the 677T allele and 677TT genotype increased along the southern-central-northern direction across Mainland China (all Pvalues≤0.001). The frequencies of the 1298C, 1298CC, 66G and 66GG genotypes decreased along the south-central-north direction across the country (all Pvalues≤0.001). Conclusions Our meta-analysis strongly indicates significant geographical and ethnic variations in the frequencies of the C677T, A1298C, and A66G gene polymorphisms in the folate metabolism pathway among Chinese populations. PMID:27089387

  15. Evaluation of C677T polymorphism of the methylenetetra hydrofolate reductase gene and its association with levels of serum homocysteine, folate, and vitamin B12 as maternal risk factors for Down syndrome

    PubMed Central

    Mohanty, Pankaj K.; Kapoor, Seema; Dubey, Anand P.; Pandey, Sanjeev; Shah, Renuka; Nayak, Hemant K.; Polipalli, Sunil K.

    2012-01-01

    AIMS AND OBJECTIVE: Evaluation of C677T polymorphisms of the methylenetetra hydrofolate reductase (MTHFR) gene and its association with level of serum homocysteine, folate, and vitamin B12 as possible maternal risk factors for Down syndrome. DESIGN: This was a case–control study. MATERIAL AND METHODS Fifty-two mothers (mean age 27.6 years) with babies having free trisomy 21 of North Indian ethnicity and 52 control nonlactating mothers (mean age 24.9 years) of same ethnicity attending services of genetic lab for bloodletting for other causes were enrolled after informed written consent. Fasting blood was collected and was used for determination of plasma homocysteine, vitamin B12, and folate (serum and RBC), and for PCR amplification of the MTHFR gene. RESULTS: The prevalence of MTHFR C677T polymorphism in north Indian mothers of babies with trisomy 21 Down syndrome was 15.38% compared to 5.88 % in controls. The difference between two groups was not statistically significant (P = 0.124). Low serum folate was demonstrated in 34.62% of cases vs. 11.54% in controls, which was significant (P = 0.005). Low RBC folate was found in 30.7% of cases versus 11.53% in controls, which was not significant (P = 0.059), when analyzed independently. But on multiple regression analysis the difference was statistically significant. Low serum vitamin B12 was found in 42.31% of cases versus 34.62% in controls, which was not significant (P = 0.118). The mean serum homocysteine in cases was 10.35 ± 0.68 while controls were 9.02 ± 0.535. CONCLUSION: Serum levels of folate were low in cases. The RBC folate levels were comparable in both groups. However the combined serum folate and RBC folate were low in cases compared to control groups. Homocysteine levels in our study were higher in Down syndrome mothers compared to controls; however high-serum level of Homocysteine had no association with MTHFR polymorphism. No association of serum vitamin B12 with MTHFR polymorphism in occurrence of

  16. Genetic polymorphisms in MTHFR (C677T, A1298C), MTR (A2756G) and MTRR (A66G) genes associated with pathological characteristics of prostate cancer in the Ecuadorian population.

    PubMed

    López-Cortés, Andrés; Jaramillo-Koupermann, Gabriela; Muñoz, María J; Cabrera, Alejandro; Echeverría, Carolina; Rosales, Felipe; Vivar, Nicolás; Paz-y-Miño, César

    2013-12-01

    The methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR) and MTR reductase (MTRR) enzymes act in the folate metabolism, which is essential in methylation and synthesis of nucleic acids. The single nucleotide polymorphisms, MTHFR C677T, A1298C, MTR A2756G and MTRR A66G, cause alteration in the homocysteine levels and reduced enzymatic activity that generates deficiency in the assimilation of folates associated with DNA damage; that is, why it is important to know if the single nucleotide polymorphisms are associated with the pathological characteristics and development of prostate cancer, through a case-control retrospective study. DNA was extracted from 110 healthy and 104 affected men. The genotypes were determined by means of the polymerase chain reaction-restriction fragment length polymorphism and confirmed with genomic sequencing. We found significant association between the genotypes of the MTHFR C677T polymorphism: C/T (odds ratio [OR] = 2.2; 95% confidence interval [CI] = 1.3-3.9; P = 0.008) and C/T + T/T (OR = 2.2; 95% CI = 1.3-3.9; P = 0.009) with the risk of prostate cancer development, and a slight association with MTRR A66G. Regarding pathological characteristics, we found significant risk between the C/T + T/T genotypes and the Gleason score (7-10) of poorly differentiated carcinoma (OR = 5.2; 95% CI = 1.7-16.2; P = 0.007). On the other hand, a significant association between A1298C, A66G, and A2756G with the pathological characteristics was not found (P > 0.05). The MTHFR C677T polymorphism has significant effects on susceptibility to prostate cancer in Ecuadorian population, especially with the Gleason grade.

  17. Homocysteine, methylenetetrahydrofolate reductase, folate status and atherothrombosis: A mechanistic and clinical perspective.

    PubMed

    Santilli, Francesca; Davì, Giovanni; Patrono, Carlo

    2016-03-01

    Observational studies consistently reported an association between plasma total homocysteine concentrations and the risk of vascular events. In contrast, data from randomized trials largely support the hypothesis that mild elevations in homocysteine level have a modest effect on cardiovascular risk. A substantial body of evidence suggests that platelet activation is, at least in part, a transducer of the effects of high homocysteine in promoting atherothrombosis. The larger treatment effect recorded in several supplementation trials by subjects not on antiplatelet agents may support this hypothesis and justify, at least in part, the success of folate therapy in primary prevention. Circulating folate and homocysteine levels as well as MTHFR genotype, while emerging as major predictors of the risk of vascular events and of the efficacy of folic acid therapy, have also proved to be determinants of an interindividual variability in the degree of lipid peroxidation and platelet activation, and of the extent of their downregulation by folic acid. This may justify a variability in folate requirements, to be further characterized with dose-finding studies using biochemical endpoints. The combination of low-dose aspirin and low-dose folate would appear to be ideally suited for the primary prevention of both coronary and cerebrovascular events, and additional clinical trials should assess the efficacy and safety of these agents.

  18. Associations of MTHFR and MTRR polymorphisms with serum lipid levels in Chinese hypertensive patients.

    PubMed

    Jiang, Shanqun; Zhao, Ruimeng; Pan, Mingluo; Venners, Scott A; Zhong, Guisheng; Hsu, Yi-Hsiang

    2014-05-01

    To examine the effects of the methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) gene polymorphisms and their interactions with environmental factors on serum lipid levels. We investigated totally 340 patients with essential hypertension, from Dongzhi community, Anhui, China. High-throughput TaqMan allelic discrimination assay was used for the genotyping of MTHFR C677T (Ala222Val), MTHFR A1298C (Glu429Ala), MTRR A66G (Ile22Met), and MTRR His595Tyr. Compared with the MTRR 66AA genotype carriers, the GG genotype carriers had lower serum total cholesterol (TC) levels (adjusted β ± standard error [SE]: -0.5 ± 0.2 mmol/L; P = .003) and low-density lipoprotein cholesterol (LDL-C) levels (adjusted β ± SE: -0.4 ± 0.2 mmol/L; P = .005). Their false discovery rate (FDR)-adjusted P values were 0.056 and 0.056, respectively. We further found that there was a statistically significant interaction between 677TT genotype and sex in their associations with LDL levels (P interaction = .020), and significant interaction between 677TT genotype and smoking on LDL levels (P interaction = .036). A similar pattern of interaction was found between 66GG and drinking on levels of TC (P interaction = .034) and LDL (P interaction = .020). However, there were no significant interactions observed after FDR adjustment. Both MTHFR and MTRR gene polymorphisms could be important genetic determinants of serum lipid levels in Chinese patients with hypertension. These findings need to be replicated in a larger sample.

  19. Single-nucleotide polymorphism in the 5-α-reductase gene (SRD5A2) is associated with increased prevalence of metabolic syndrome in chemotherapy-treated testicular cancer survivors.

    PubMed

    Boer, Hink; Westerink, Nico-Derk L; Altena, Renske; Nuver, Janine; Dijck-Brouwer, D A Janneke; van Faassen, Martijn; Klont, Frank; Kema, Ido P; Lefrandt, Joop D; Zwart, Nynke; Boezen, H Marike; Smit, Andries J; Meijer, Coby; Gietema, Jourik A

    2016-02-01

    Chemotherapy-treated testicular cancer survivors are at risk for development of the metabolic syndrome, especially in case of decreased androgen levels. Polymorphisms in the gene encoding steroid 5-α-reductase type II (SRD5A2) are involved in altered androgen metabolism. We investigated whether single-nucleotide polymorphisms (SNPs) rs523349 (V89L) and rs9282858 (A49T) in SRD5A2 are associated with cardiometabolic status in testicular cancer survivors. In 173 chemotherapy-treated testicular cancer survivors, hormone levels and cardiometabolic status were evaluated cross-sectionally (median 5 years [range 3-20] after chemotherapy) and correlated with SNPs in SRD5A2. The metabolic syndrome was more prevalent in survivors who were homozygous or heterozygous variant for SRD5A2 rs523349 compared to wild type (33% versus 19%, P = 0.032). In particular, patients with lower testosterone levels (<15 nmol/l) and a variant genotype showed a high prevalence of the metabolic syndrome (66.7%). Mean intima-media thickness of the carotid artery and urinary albumin excretion, both markers of vascular damage, were higher in the group of survivors homozygous or heterozygous variant for rs523349 (0.62 versus 0.57 mm, P = 0.026; 5.6 versus 3.1 mg/24 h, P = 0.017, respectively). No association was found between cardiometabolic status and SNP rs9282858 in SRD5A2. Metabolic syndrome develops more frequently in testicular cancer survivors homozygous or heterozygous variant for SNP rs523349 in SRD5A2. Altered androgen sensitivity appears to be involved in the development of adverse metabolic and vascular changes in testicular cancer survivors and is a target for intervention. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Association of MTHFR A1298C polymorphism with conotruncal heart disease.

    PubMed

    Sayin Kocakap, Beyza D; Sanli, Cihat; Cabuk, Feryal; Koc, Murat; Kutsal, Ali

    2015-10-01

    Congenital heart diseases are common congenital anomalies with 1% prevalence worldwide and are associated with significant childhood morbidity and mortality. Among a wide range of aetiologically heterogeneous conditions, conotruncal anomalies account for approximately one-third of all congenital heart defects. The aetiology of conotruncal heart diseases is complex, with both environmental and genetic causes. Hyperhomocysteinaemia, which is often accompanied by the defects of folic acid metabolism, is known to cause conotruncal heart anomalies. In this study, we have evaluated three polymorphisms in the following two hyperhomocysteinaemia-related genes: methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and nicotinamide N-methyl transferase (NNMT rs694539) in 79 children with conotruncal heart disease and 99 children without conotruncal heart disease. Genotype distribution of the MTHFR A1298C polymorphism showed a statistically significant difference between the two groups. In the case group, AC and CC genotypes were higher than the control group (p<0.05). We have found that MTHFR A1298C polymorphism is associated with conotruncal heart disease; C allele (p=0.028), AC (OR[95% CI]=2.48[1.24-4.95], p=0.010), CC (OR[95% CI]=3.01[1.16-7.83], p=0.023), and AC+CC (OR[95% CI]=2.60[1.36-4.99], p=0.004) genotypes are more frequent in the patient group. Genotype distributions of the MTHFR C677T and NNMT rs694539 polymorphisms were similar in the two groups when evaluated separately and also according to the dominant genetic model (p>0.05). Our results suggest that MTHFR 1298C allele is a risk factor for conotruncal heart disease.

  1. DNA promoter methylation in breast tumors: No association with genetic polymorphisms in MTHFR and MTR

    PubMed Central

    Tao, Meng Hua; Shields, Peter G.; Nie, Jing; Marian, Catalin; Ambrosone, Christine B.; McCann, Susan E.; Platek, Mary; Krishnan, Shiva S.; Xie, Bin; Edge, Stephen B.; Winston, Janet; Vito, Dominica; Trevisan, Maurizio; Freudenheim, Jo L.

    2013-01-01

    Aberrant promoter methylation is recognized as an important feature of breast carcinogenesis. We hypothesized that genetic variation of genes for methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MTR), two critical enzymes in one-carbon metabolism, may alter DNA methylation levels, and thus influence DNA methylation in breast cancer. We evaluated case-control association of MTHFR C677T, A1298C, and MTR A2756G polymorphisms for cases strata defined by promoter methylation status for each of three genes, E- cadherin, p16, and RAR-β2 in breast cancer; in addition, we evaluated case-case comparisons of likelihood of promoter methylation in relation to genotypes using a population-based case-control study conducted in Western New York State. Methylation was evaluated with real time methylation-specific PCRs for 803 paraffin embedded breast tumor tissues from women with primary, incident breast cancer. We applied unordered polytomous regression and unconditional logistic regression to derive adjusted odds ratios (OR) and 95% confidence intervals (CI). We did not find any association of MTHFR and MTR polymorphisms with breast cancer risk stratified by methylation status nor between polymorphisms and likelihood of promoter methylation of any of the genes. There was no evidence of difference within strata defined by menopausal status, ER status, folate intake and lifetime alcohol consumption. Overall, we found no evidence that these common polymorphisms of the MTHFR and MTR genes are associated with promoter methylation of E- cadherin, p16, and RAR-β2 genes in breast cancer. PMID:19240236

  2. Combined genotype and haplotype distributions of MTHFR C677T and A1298C polymorphisms

    PubMed Central

    Fan, Shujun; Yang, Boyi; Zhi, Xueyuan; Wang, Yanxun; Zheng, Quanmei; Sun, Guifan

    2016-01-01

    Abstract Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms are, independently and/or in combination, associated with many disorders. However, data on the combined genotype and haplotype distributions of the 2 polymorphisms in Chinese population were limited. We recruited 13,473 adult women from 9 Chinese provinces, collected buccal cell samples, and determined genotypes, to estimate the combined genotype and haplotype distributions of the MTHFR C677T and A1298C polymorphisms. In the total sample, the 6 common combined genotypes were CT/AA (29.5%), TT/AA (21.9%), CC/AA (15.4%), CC/AC (14.9%), CT/AC (13.7%), and CC/CC (3.4%); the 3 frequent haplotypes were 677T-1298A (43.6%), 677C-1298A (37.9%), and 677C-1298C (17.6%). Importantly, we observed that there were 51 (0.4%) individuals with the CT/CC genotype, 92 (0.7%) with the TT/AC genotype, 17 (0.1%) with the TT/CC genotype, and that the frequency of the 677T-1298C haplotype was 0.9%. In addition, the prevalence of some combined genotypes and haplotypes varied among populations residing in different areas and even showed apparent geographical gradients. Further linkage disequilibrium analysis showed that the D’ and r2 values were 0.883 and 0.143, respectively. In summary, the findings of our study provide further strong evidence that the MTHFR C677T and A1298C polymorphisms are usually in trans and occasionally in cis configurations. The frequencies of mutant genotype combinations were relatively higher in Chinese population than other populations, and showed geographical variations. These baseline data would be useful for future related studies and for developing health management programs. PMID:27902594

  3. MTHFR Gene Polymorphism-Mutations and Air Pollution as Risk Factors for Breast Cancer

    PubMed Central

    Gonzales, Mildred C.; Yu, Pojui; Shiao, S. Pamela K.

    2017-01-01

    Background The methylenetetrahydrofolate reductase gene (MTHFR) is one of the most investigated genes associated with breast cancer for its role in epigenetic pathways. Objectives The objectives of this metaprediction study were to examine the polymorphism-mutation risk subtypes of MTHFR and air pollution as contributing factors for breast cancer. Methods For triangulation purposes in metapredictive analyses, we used a recursive partition tree, nonlinear association curve fit, and heat maps for data visualization, in addition to the conventional comparison procedure and pooled analyses. Results We included 36,683 breast cancer cases and 40,689 controls across 82 studies for MTHFR 677 and 23,252 cases and 27,094 controls across 50 studies for MTHFR 1298. MTHFR 677 TT was a risk genotype for breast cancer (p = .0004) and in the East Asian subgroup (p = .005). On global maps, the most polymorphism-mutations on MTHFR 677 TT were found in the Middle East, Europe, Asia, and the Americas, whereas the most mutations on MTHFR 1298 CC were located in Europe and the Middle East for the control group. The geographic information system maps further revealed that MTHFR 677 TT mutations yielded a higher risk of breast cancer for Australia, East Asia, the Middle East, South Europe, Morocco, and the Americas and that MTHFR 1298 CC mutations yielded a higher risk in Asia, the Middle East, South Europe, and South America. Metapredictive analysis revealed that air pollution level was significantly associated with MTHFR 677 TT polymorphism-mutation genotype. Discussion We present the most comprehensive analyses to date of MTHFR polymorphism-mutations and breast cancer risk. Future nursing studies are needed to investigate the health impact on breast cancer of epigenetics and air pollution across populations. PMID:28114181

  4. Association of MTHFR (C677T) Gene Polymorphism With Breast Cancer in North India

    PubMed Central

    Waseem, Mohammad; Hussain, Syed Rizwan; Kumar, Shashank; Serajuddin, Mohammad; Mahdi, Farzana; Sonkar, Satyendra Kumar; Bansal, Cherry; Ahmad, Mohammad Kaleem

    2016-01-01

    BACKGROUND Breast cancer is one of the most common malignancies in women and is associated with a variety of risk factors. The functional single-nucleotide polymorphism (SNP) C677T in the gene encoding 5,10-methylenetetrahydrofolate reductase (MTHFR) may lead to decreased enzyme activity and affect the chemosensitivity of tumor cells. This study was designed to investigate the association of MTHFR gene polymorphism (SNP) in the pathogenesis of breast cancer among the North Indian women population. MATERIALS AND METHODS Genotyping was performed by polymerase chain reaction (PCR) using genomic DNA, extracted from the peripheral blood of subjects with (275 cases) or without (275 controls) breast cancer. Restriction fragment length polymorphism was used to study C677T polymorphism in the study groups. RESULTS The distribution of MTHFR (C677T) genotype frequencies, ie, CC, TT, and CT, among the patients was 64.7%, 2.18%, and 33.09%, respectively. In the healthy control group, the CC, TT, and CT frequencies were 78.91%, 1.09%, and 20.1%, respectively. The frequencies of C and T alleles were 81.2% and 18.7%, respectively, in the patient subjects, while they were 88.9% and 11.09%, respectively, among the healthy control group. Frequencies of the CT genotype and the T allele were significantly different (P = 0.007 and P = 0.005, respectively) between the control and the case subjects. CONCLUSION This study shows an association of the CT genotype and the T allele of the MTHFR (C667T) gene with increased genetic risk for breast cancer among Indian women. PMID:27721657

  5. DNA promoter methylation in breast tumors: no association with genetic polymorphisms in MTHFR and MTR.

    PubMed

    Tao, Meng Hua; Shields, Peter G; Nie, Jing; Marian, Catalin; Ambrosone, Christine B; McCann, Susan E; Platek, Mary; Krishnan, Shiva S; Xie, Bin; Edge, Stephen B; Winston, Janet; Vito, Dominica; Trevisan, Maurizio; Freudenheim, Jo L

    2009-03-01

    Aberrant promoter methylation is recognized as an important feature of breast carcinogenesis. We hypothesized that genetic variation of genes for methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MTR), two critical enzymes in the one-carbon metabolism, may alter DNA methylation levels and thus influence DNA methylation in breast cancer. We evaluated case-control association of MTHFR C677T, A1298C, and MTR A2756G polymorphisms for cases strata-defined by promoter methylation status for each of three genes, E-cadherin, p16, and RAR-beta2 in breast cancer; in addition, we evaluated case-case comparisons of the likelihood of promoter methylation in relation to genotypes using a population-based case-control study conducted in Western New York State. Methylation was evaluated with real-time methylation-specific PCRs for 803 paraffin-embedded breast tumor tissues from women with primary, incident breast cancer. We applied unordered polytomous regression and unconditional logistic regression to derive adjusted odds ratios and 95% confidence intervals. We did not find any association of MTHFR and MTR polymorphisms with breast cancer risk stratified by methylation status nor between polymorphisms and likelihood of promoter methylation of any of the genes. There was no evidence of difference within strata defined by menopausal status, estrogen receptor status, folate intake, and lifetime alcohol consumption. Overall, we found no evidence that these common polymorphisms of the MTHFR and MTR genes are associated with promoter methylation of E-cadherin, p16, and RAR-beta2 genes in breast cancer.

  6. MTHFR gene C677T mutation and ACE gene I/D polymorphism in Turkish patients with osteoarthritis.

    PubMed

    Inanir, Ahmet; Yigit, Serbulent; Tural, Sengul; Cecen, Osman; Yildirim, Eren

    2013-01-01

    Osteoarthritis is a degenerative joint disorder resulting in destruction of articular cartilage, osteophyte formation, and subchondral bone sclerosis. In recent years, numerous genetic factors have been identified and implicated in osteoarthritis. The aim of the current study was to examine the influence of methylenetetrahydrofolate reductase (MTHFR) gene C677T mutation and angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) variations on the risk of osteoarthritis. Genomic DNA is obtained from 421 persons (221 patients with osteoarthritis and 200 healthy controls). ACE gene I/D polymorphism genotypes were determined using polymerase chain reaction using I and D allele-specific primers. The MTHFR C677T mutation was analyzed by polymerase chain reaction (PCR) based restriction fragment length polymorphism (RFLP) methods. We found significant difference between the groups with respect to both ACE and MTHFR genotype distributions (p< 0.001, p< 0.001 respectively). Our study suggests that ACE gene DD genotype and MTHFR gene CC genotype could be used as genetic markers in osteoarthritis in Turkish study populations.

  7. Role of MTHFR C677T and MTR A2756G polymorphisms in thyroid and breast cancer development.

    PubMed

    Zara-Lopes, T; Gimenez-Martins, A P A; Nascimento-Filho, C H V; Castanhole-Nunes, M M U; Galbiatti-Dias, A L S; Padovani-Júnior, J A; Maniglia, J V; Francisco, J L E; Pavarino, E C; Goloni-Bertollo, E M

    2016-05-09

    Folate metabolism is essential for DNA synthesis and repair. Alterations in genes that participate in folate metabolism can be associated with several types of malignant neoplasms, including thyroid and breast cancer. In the present case-control study, we examined the association between methylenetetrahydrofolate reductase (MTHFR C677T, rs1801133) and methionine synthase (MTR A2756G, rs1805087) polymorphisms and risk for thyroid and breast cancer. Polymerase chain reaction-restriction fragment length technique was used to determine the specific genotypes in the genes of interest. Statistical analysis was performed by multiple logistic regression test. We found an association between MTHFR C677T polymorphism and risks to both thyroid (OR = 2.50; 95%CI = 1.15-5.46; P = 0.02) and breast cancer (OR = 2.53; 95%CI = 1.08-5.93; P = 0.03). Tobacco consumption and high body mass index were also associated with thyroid cancer. In addition, increased age (≥50 years) and alcohol consumption were found to be associated with breast cancer. Our results indicated that MTHFR C677T is significantly associated with thyroid and breast cancer risks. Thus, these factors may be used as potential prognostic markers for thyroid and breast cancers.

  8. Does the MTHFR C677T gene polymorphism indicate cardiovascular disease risk in type 2 diabetes mellitus patients?

    PubMed

    Bahadır, Anzel; Eroz, Recep; Türker, Yasin

    2015-07-01

    Diabetes mellitus is a major risk factor for cardiovascular disease (CVD). We investigated the relationship among biochemical and cardiac risk parameters with the methylenetetrahydrofolate reductase (MTHFR) C677T genotype in type 2 diabetes mellitus (T2DM) patients. One hundred seven T2DM subjects with severe CVD diagnosed by angiography were included consecutively in this cross-sectional study. Biochemical and clinical parameters were obtained from patients who were not positive for nephropathy and retinopathy. MTHFR C677T genotypes were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Normally and abnormally distributed continuous variables were analyzed using student t- and Mann-Whitney U tests. Categorical variables were analyzed using chi-square test. In the study, 31 T2DM subjects had the CC (29.0%), 62 had the CT (57.9%), and 14 had the TT (13.1%) genotypes. There were no significant differences between subjects with wild-type (677CC) and with mutant (677CT+677TT) alleles in terms of diabetes duration, visceral fat area, total cholesterol, triglyceride, fasting plasma glucose, systolic blood pressure, diastolic blood pressure, high-sensitivity C-reactive protein, homocysteine (Hcy), and carotid intima-media thickness values. This study suggests that MTHFR gene polymorphisms can not be used as a marker for the assessment of cardiovascular risk in T2DM patients.

  9. Does the MTHFR C677T gene polymorphism indicate cardiovascular disease risk in type 2 diabetes mellitus patients?

    PubMed Central

    Bahadır, Anzel; Eroz, Recep; Türker, Yasin

    2015-01-01

    Objective: Diabetes mellitus is a major risk factor for cardiovascular disease (CVD). We investigated the relationship among biochemical and cardiac risk parameters with the methylenetetrahydrofolate reductase (MTHFR) C677T genotype in type 2 diabetes mellitus (T2DM) patients. Methods: One hundred seven T2DM subjects with severe CVD diagnosed by angiography were included consecutively in this cross-sectional study. Biochemical and clinical parameters were obtained from patients who were not positive for nephropathy and retinopathy. MTHFR C677T genotypes were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Normally and abnormally distributed continuous variables were analyzed using student t- and Mann-Whitney U tests. Categorical variables were analyzed using chi-square test. Results: In the study, 31 T2DM subjects had the CC (29.0%), 62 had the CT (57.9%), and 14 had the TT (13.1%) genotypes. There were no significant differences between subjects with wild-type (677CC) and with mutant (677CT+677TT) alleles in terms of diabetes duration, visceral fat area, total cholesterol, triglyceride, fasting plasma glucose, systolic blood pressure, diastolic blood pressure, high-sensitivity C-reactive protein, homocysteine (Hcy), and carotid intima-media thickness values. Conclusion: This study suggests that MTHFR gene polymorphisms can not be used as a marker for the assessment of cardiovascular risk in T2DM patients. PMID:25537992

  10. Role of MTHFR C677T gene polymorphism in the susceptibility of schizophrenia: An updated meta-analysis.

    PubMed

    Yadav, Upendra; Kumar, Pradeep; Gupta, Sanjay; Rai, Vandana

    2016-04-01

    Methylenetetrahydrofolate reductase (MTHFR) is the key enzyme of folate/homocysteine metabolic pathway. C677T polymorphism of MTHFR gene was reported as risk factor for congenital defects, metabolic and neuropsychiatric disorders. Numerous case-control studies investigated C677T polymorphism as risk factor for schizophrenia but results of these studies were contradictory. To draw a conclusion, a meta-analysis of all available case-control studies was performed. PubMed, Google Scholar, Springer Link and Elsevier databases were searched for eligible case-control studies. Pooled odds ratio with 95%CI was used as an association measure and all statistical analyses were performed by Open Meta-Analyst and MIX software. Total 38 studies with 10,069 cases and 13,372 controls were included in the present meta-analysis. Results of meta-analysis showed significant associated between C677T polymorphism and risk of schizophrenia (ORTvsC=1.18, 95%CI=1.10-1.27, p=<0.001; ORCTvsCC=1.10, 95%CI=1.04-1.17, p=<0.001; ORTTvsCC=1.40, 95%CI=1.20-1.64, p=<0.001; ORTT+CTvsCC=1.19, 95%CI=1.09-1.30, p=<0.001). We also performed subgroup and sensitivity analyses. Subgroup analysis was done according to ethnicity and significant association was found between C677T polymorphism and risk of schizophrenia in all three ethnic populations-African (OR=2.51; 95%CI=1.86-3.40; p=<0.001), Asian (OR=1.21; 95%CI=1.10-1.33; p=<0.001) and Caucasian (OR=1.07; 95%CI=1.01-1.14; p=0.01). In conclusion the results of the present meta-analysis suggested that the MTHFR C677T polymorphism is a risk factor for schizophrenia.

  11. Molecular Cloning, Expression Pattern and Polymorphisms of NADPH-Cytochrome P450 Reductase in the Bird Cherry-Oat Aphid Rhopalosiphum padi (L.)

    PubMed Central

    Zuo, Yayun; Li, Yuting

    2016-01-01

    NADPH–cytochrome P450 reductase (CPR) plays an important role in the cytochrome P450 (CYP)-mediated metabolism of endogenous and exogenous substrates. CPR has been found to be associated with insecticide metabolism and resistance in many insects. However, information regarding CPR in the bird cherry-oat aphid, Rhopalosiphum padi, is unavailable. In the current study, a full-length cDNA (2,476 bp) of CPR (RpCPR) encoding 681 amino acids was cloned from R. padi. Nucleotide sequence and deduced amino acid sequence analysis showed that RpCPR exhibits characteristics of classical CPRs and shares high identities with those of other insects, especially with the pea aphid, Acyrthosiphon pisum. The mRNA of RpCPR was expressed at all developmental stages, with the highest expression level found in the second instar and the lowest in adult. Expression levels of RpCPR in isoprocarb-resistant and imidacloprid-resistant strains were 3.74- and 3.53-fold higher, respectively, than that of a susceptible strain. RpCPR expression could also be induced by low concentrations (LC30) of isoprocarb and imidacloprid. Moreover, we sequenced the open reading frame (ORF) of RpCPR from 167 field samples collected in 11 geographical populations. Three hundred and thirty-four SNPs were detected, of which, 65 were found in more than two individuals. One hundred and ninety-four missense mutations were present in the amino acid sequence, of which, the P484S mutant had an allele frequency of 35.1%. The present results suggest that RpCPR may play an important role in the P450-mediated insecticide resistance of R. padi to isoprocarb and imidacloprid and possibly other insecticides. Meanwhile, RpCPRmaintains high genetic diversity in natural individuals, which provides the possibility of studying potential correlations between variants and certain special physiological characters. PMID:27124302

  12. Association of the Maternal MTHFR C677T Polymorphism with Susceptibility to Neural Tube Defects in Offsprings: Evidence from 25 Case-Control Studies

    PubMed Central

    Zou, Peng; Ji, Guixiang; Gu, Aihua; Zhao, Peng

    2012-01-01

    Background Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and is involved in DNA methylation, DNA synthesis, and DNA repair. In addition, it is a possible risk factor in neural tube defects (NTDs). The association of the C677T polymorphism in the MTHFR gene and NTD susceptibility has been widely demonstrated, but the results remain inconclusive. In this study, we performed a meta-analysis with 2429 cases and 3570 controls to investigate the effect of the MTHFR C677T polymorphism on NTDs. Methods An electronic search of PubMed and Embase database for papers on the MTHFR C677T polymorphism and NTD risk was performed. All data were analysed with STATA (version 11). Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association. Sensitivity analysis, test of heterogeneity, cumulative meta-analysis, and assessment of bias were performed in our meta-analysis. Results A significant association between the MTHFR C677T polymorphism and NTD susceptibility was revealed in our meta-analysis ( TT versus CC: OR  = 2.022, 95% CI: 1.508, 2.712; CT+TT versus CC: OR  = 1.303, 95% CI: 1.089, 1.558; TT versus CC+CT: OR  = 1.716, 95% CI: 1.448, 2.033; 2TT+CT versus 2CC+CT: OR  = 1.330, 95% CI: 1.160, 1.525). Moreover, an increased NTD risk was found after stratification of the MTHFR C677T variant data by ethnicity and source of controls. Conclusion The results suggested the maternal MTHFR C677T polymorphism is a genetic risk factor for NTDs. Further functional studies to investigate folate-related gene polymorphisms, periconceptional multivitamin supplements, complex interactions, and the development of NTDs are warranted. PMID:23056169

  13. Dietary intake of folate, vitamin B2, vitamin B6, vitamin B12, genetic polymorphism of related enzymes, and risk of breast cancer: a case-control study in Japan.

    PubMed

    Ma, Enbo; Iwasaki, Motoki; Kobayashi, Minatsu; Kasuga, Yoshio; Yokoyama, Shiro; Onuma, Hiroshi; Nishimura, Hideki; Kusama, Ritsu; Tsugane, Shoichiro

    2009-01-01

    We investigated associations among intake of folate, vitamin B2, vitamin B6, vitamin B12, and polymorphisms of 5,10-