Association Of Methylenetetrahydrofolate Reductase Polymorphisms Research Articles

Association of MTHFR polymorphism, folic acid and vitamin B12 with serum homocysteine levels in pregnant women.

Homocysteine is known to be associated with adverse vascular and metabolic effects, as well as pregnancy complications. Its serum levels are influenced by the function of the enzyme methylenetetrahydrofolate reductase (MTHFR) and the dietary intake of folic acid, vitamin B12, and methionine. In this cross-sectional study, we investigated the association of genetic polymorphisms of the MTHFR gene with vitamin status in pregnant women during mandatory folic acid supplementation. The study included 102 pregnant women between 24 and 28 weeks of gestation who were attending regular outpatient examinations at the maternity clinic. Homocysteine, folic acid, vitamin B12 levels, and MTHFR gene polymorphisms (C677T and A1298C) were analyzed. Significant associations were found between vitamin B12 and folic acid levels with homocysteine (P < 0.001), with lower serum levels of these vitamins being associated with higher homocysteine levels. Surprisingly, there was no significant association between MTHFR genetic polymorphisms and serum homocysteine levels, likely attributed to the supplementation of folic acid and vitamin B12 in vitamin supplements for pregnant women, which counteracts the effect of the mutation. Remarkably, a high prevalence of MTHFR gene mutations was found, with the C677T polymorphism present in 56.9% and the A1298C polymorphism in 87.2% of pregnant women. These findings emphasize the importance of adequate folic acid and vitamin B12 intake during pregnancy to regulate homocysteine levels. Although the MTHFR gene mutations were highly prevalent, their influence on homocysteine levels in this population appears to be mitigated by vitamin supplementation. Further research is warranted to explore the impact of these mutations on other aspects of pregnancy outcomes. The trial is registrated at Clinicaltrail.gov (NCT04952324).

Association of MTHFR Polymorphisms With Leukoencephalopathy Risk in Patients With Primary CNS Lymphoma Treated With Methotrexate-Based Regimens.

The folate antagonist high-dose methotrexate (HD-MTX) is integral to induction chemotherapy for primary CNS lymphoma (PCNSL); however, it can be associated with leukoencephalopathy. Methylenetetrahydrofolate reductase (MTHFR) is involved in intracellular folate depletion. We assessed whether MTHFR polymorphisms affect the risk of leukoencephalopathy. We retrospectively searched our database at the Massachusetts General Hospital for newly diagnosed PCNSL treated with HD-MTX (without radiotherapy nor intrathecal chemotherapy). Among 68 patients with PCNSL, MTHFR polymorphisms were found in 60 individuals (88.2%) including a 677C→T genotype, a 1298A→C genotype, or a combined 677C→T/1298A→C genotype. Neither MTX clearance nor response to induction therapy was affected by specific genotypes, and complete response was achieved in 72.1% of patients by HD-MTX-based induction. However, the 1298A→C genotype was associated with increased frequency and severity of leukoencephalopathy over time (odds ratio 4.0, CI 1.5-11.4). Such genotype predicted treatment-induced leukoencephalopathy with a sensitivity of 71.0% and a specificity of 62.2% (area under the curve 0.67, CI 0.5-0.8; p = 0.019). While progression-free survival did not differ in genotype-based subgroups, overall survival was lower for the 1298A→C genotype. The MTHFR 1298A→C genotype may serve to identify patients with PCNSL at elevated risk of HD-MTX-induced leukoencephalopathy. This seems to translate into reduced survival, potentially due to decreased functional status.

Association of methylenetetrahydrofolate reductase polymorphism and male infertility in type 2 diabetes mellitus patients

INTRODUCTION: As per World Health Organization, Infertility is a condition which is characterized by not getting conceived with more than 1-year of unprotected sexual intercourse without usage of any contraceptive aids. Folate has a significant role in the metabolism of the cells, like nucleic acids synthesis, gene expression by means of remethylation of the homocysteine into methionine. In the males, deficiency of folate leads to reduced proliferation of the sperm cells. Polymorphisms of methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase genes result in alterations of the methylations resulting pathological conditions being a potential risk factor for male infertility. MATERIALS AND METHODS: A total of 100 diabetic infertile males were selected as the study group and 100 nondiabetic fertile males were included as the control group. Blood samples were analyzed for the MTHFR polymorphisms. DNA extraction was done and the extract is subjected to polymerase chain reaction amplification. The resultant is subjected to electrophoresis for MTHFR gene allele confirmation. Statistical analysis was done using IBM SPSS Statistics 20 package. Chi-square test, odds ratio has been done and P &lt; 0.05 is considered statistically significant. RESULTS: Genotype frequencies of MTHFR C677T, A1298C in all the subjects were analyzed for the Hardy–Weinberg law of genetic equilibrium. Mutant polymorphisms of MTHFR C677T, i.e., thymine-thymine and cytosine-thymine were increased significantly. Similarly, MTHFR A1298C mutant polymorphisms, i.e. adenine-cytosine, cytosine-cytosine were increased significantly in the infertile group than in the fertile group. DISCUSSION: Mutations of both MTHFR C677T, A1298C are found to be linked with lowered enzyme activity. We found that the occurrence of mutant homozygous and mutant heterozygous genotypes was increased in a diabetic male infertile group when compared to nondiabetic fertile group. Hence, it can be concluded that presence of single-nucleotide polymorphisms of MTHFR will increase the risk of infertility in diabetic male population.

Association of MTHFR polymorphisms with nsCL/P in Chinese Uyghur population

BackgroundnsCL/P (nonsyndromic cleft lip with or without cleft palate) is a complex disorder with a multifactorial etiology that involves both genetic and environmental factors. A number of studies identified that MTHFR (methylenetetrahydrofolate reductase) was associated with nsCL/P in different populations. AimIn this study, we aim to investigate the association between the polymorphism in MTHFR gene (rs1801131, rs1801133) and nsCL/P in Chinese Uyghur population. Subjects and methodsWe conducted a case–control study comparing 120 nsCL/P patients to 100 controls. The distribution of MTHFR genotypes and frequency of alleles were compared between patients and controls by chi-square test. The odds ratios (OR) and corresponding 95% confidence intervals (95% CIs) were calculated to estimate the strength of association of MTHFR gene (C677T and A1298C). ResultsFor rs1801131, allele C frequency was higher in cases than in controls (30.4%>19.0%), and the difference was statistically significant (χ2=7.538, P=0.006). The genotype distribution at rs1801131 was different between cases (AC>AA>CC, 49.2%>45.0%>5.8%) and controls (AA>AC>CC, 65.0%>32.0%>3.0%), and the difference was statistically significant (χ2=8.883, P=0.012). AC genotype was found to increase the susceptibility of nsCL/P (OR=2.219, 95% CI=1.266–3.892, P=0.005). No association was found between rs1801133 and nsCL/P. ConclusionThis study indicated that rs1801131 polymorphism in MTHFR was associated with nsCL/P in Chinese Uyghur population. Given the unique genetic and environmental characters of the Uyghur population, these findings may be helpful for exploring the pathogenesis of this complex disease.

THU0144 The Influence of the Methylenetetrahydrofolate Reductase (MTHFR) Polymorphism on Methotrexate Treatment Outcome in Patients with Rheumatoid Arthritis in the EAST Bohemian Region

BackgroundIdentifying genetic predictors of methotrexate (MTX) therapy response in patients with rheumatoid arthritis (RA) may have importance for clinical benefit optimalization. MTX therapeutic effect is achieved by inhibiting enzymes of...

Association between MTHFR Gene Polymorphism and the Risk of Ovarian Cancer: A Meta-analysis of the Literature

Methylenetetrahydrofolate reductase (MTHFR) is an essential enzyme for DNA biosynthesis and the epigenetic process of DNA methylation. MTHFR gene polymorphisms have been implicated as risk factors for several types of cancers. However, reports on the association of MTHFR polymorphisms with ovarian cancers are inconclusive. The aim of this study is to summarize on the reported data and meta-analytically investigate the relationship between the MTHFR C677T and A1298C polymorphism and the risk of ovarian cancer. We searched for all published articles indexed in MEDLINE (1950-2012), EMBASE (1974-2012), and CNKI (1994-2012). Case-control or cohort studies that relating to MTHFR polymorphism and ovarian cancer women were included and data were extracted independently by two reviewers. The search yielded 21 articles, from which 7 studies met the inclusion criteria. We performed a metaanalysis involving 3493 patients with ovarian cancer and 3863 controls with Review Manager 5.1 software. Odds ratio (OR) and 95% confidence intervals (CIs) were used to evaluate the ovarian cancer risk. All the available data considered together, no association between the MTHFR C677T polymorphism and ovarian cancer risk was found in any genetic variations. However, in the subgroup analysis by ethnicity of Asian and Caucasian, MTHFR 677T was associated with significantly increased ovarian cancer risk among Asian [T allele vs. C allele: OR=1.50, 95% CI: 1.25-1.81, P<0.0001; CT + TT vs. CC (dominant model): OR=1.49, 95% CI: 1.18-1.88, P=0.0009; TT vs. CT + CC (recessive model): OR=2.33, 95% CI: 1.57-3.45, P<0.00001], while, there was no significant increased risk in Caucasian. As for MTHFR A1298C polymorphism, no marked association was found in either group of Caucasian population, while no data was available to analyze in Asian population. The C677T polymorphism of the MTHFR gene is associated with the susceptibility of ovarian cancer in Asian population, suggesting that TT genotype may serve as a risk factor of ovarian cancer among Asian but not Caucasians. In addition, there is no association between A1298C gene polymorphism and ovarian cancer, including Caucasian and Asian women.

Association between MTHFR Gene Polymorphisms and the Risk of Autism Spectrum Disorders: A Meta‐Analysis

Methylenetetrahydrofolate reductase (MTHFR) is essential for DNA biosynthesis and the epigenetic process of DNA methylation, and its gene polymorphisms have been implicated as risk factors for birth defects, neurological disorders, and cancers. However, reports on the association of MTHFR polymorphisms with autism spectrum disorders (ASD) are inconclusive. Therefore, we investigated the relationship of the MTHFR polymorphisms (C677T and A1298C) and the risk of ASD by meta-analysis. Up to December 2012, eight case-control studies involving 1672 patients with ASD and 6760 controls were included for meta-analysis. The results showed that the C677T polymorphism was associated with significantly increased ASD risk in all the comparison models [T vs. C allele (frequency of allele): odds ratio (OR) = 1.42, 95% confidence interval (CI): 1.09-1.85; CT vs. CC (heterozygote): OR = 1.48, 95% CI: 1.09-2.00; TT vs. CC (homozygote): OR = 1.86, 95% CI: 1.08-3.20; CT+TT vs. CC (dominant model): OR = 1.56, 95% CI: 1.12-2.18; and TT vs. CC+CT (recessive model): OR = 1.51, 95% CI: 1.02-2.22], whereas the A1298C polymorphism was found to be significantly associated with reduced ASD risk but only in a recessive model (CC vs. AA+AC: OR = 0.73, 95% CI: 0.56-0.97). In addition, we stratified the patient population based on whether they were from a country with food fortification of folic acid or not. The meta-analysis showed that the C677T polymorphism was found to be associated with ASD only in children from countries without food fortification. Our study indicated that the MTHFR C677T polymorphism contributes to increased ASD risk, and periconceptional folic acid may reduce ASD risk in those with MTHFR 677C>T polymorphism.

Association of methylenetetrahydrofolate reductase polymorphisms with susceptibility to Alzheimer's disease

BackgroundGenetic risk factors play an important role in the pathogenesis of Alzheimer's disease (AD). In this case-control study, we examined the C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and their correlation with this pathology. ObjectiveTo verify the association between MTHFR C677T and A1298C polymorphisms and Alzheimer's disease. MethodThis work was conducted as a case–control study. Cases consisted of thirty-eight patients and 100 individuals without dementia constituted the control group. Genotyping of MTHFR polymorphisms was performed on patients and controls. ResultGenetic analyses did not indicate a significant association between the MTHFR C677T mutation and AD (C/T: 63.15% versus 39%, p=0.087). However, the genotype prevalence of the missense variant MTHFR A1298C was significantly different between patients and controls (A/C: 55% versus 7%, p<10−3). Our data suggest an association between the MTHFR A1298C mutation and AD; however, the MTHFR C677T mutation did not contribute to susceptibility for AD. ConclusionThe MTHFR A1298C polymorphism is a possible risk factor for Alzheimer's disease.

Methylene tetrahydrofolate reductase gene polymorphisms and their association with methotrexate toxicity

A systematic review and a meta-analysis were conducted, to investigate the possible association of methylene tetrahydrofolate reductase (MTHFR) gene polymorphisms with adverse effects related to methotrexate (MTX). A systematic literature search in PubMed retrieved a total of 44 studies (42 unique articles). Two polymorphisms were included in the meta-analysis: C677T and A1298C. Random effect models were used in the analysis. Odds ratios along with their 95% confidence intervals were computed to compare the distribution of alleles and genotypes between cases and controls. The analysis highlighted a significant association of C677T polymorphism with overall MTX toxicity, hepatotoxicity, hematological toxicity, and neurotoxicity. It also revealed an association with MTX toxicity in patients with rheumatoid arthritis. In contrast, a protective effect of C677T MTHFR polymorphism on acute graft-versus-host disease and on patients treated with hematopoietic cell transplantation was found. As for the A1298C polymorphism, a statistically significant association with overall MTX toxicity and a protective role of the polymorphism in rheumatoid arthritis patients was detected. These results indicate the association of MTHFR polymorphisms with MTX toxicity. However, further studies are needed to reveal the underlying biological mechanism of the association.

Methylenetetrahydrofolate reductase polymorphisms, C677T and A1298C, are associated with methotrexate-related toxicities in Korean patients with rheumatoid arthritis

We investigated associations between the methylenetetrahydrofolate reductase (MTHFR) polymorphisms C677T and A1298C and methotrexate (MTX)-related toxicities in Korean patients with rheumatoid arthritis (RA) taking MTX. One hundred sixty-seven patients with RA were enrolled in a cross-sectional study and genotyped for the single-nucleotide polymorphisms C677T and A1298C in MTHFR. Alleles, genotypes, and haplotypes of the C677T and A1298C polymorphisms were not associated with specific MTX toxicities. However, among RA patients with the 1298CC genotype, the proportion who experienced at least one toxicity was significantly greater than the proportion of patients with 1298AA who did (P=0.043). In addition, the proportion of patients with the 677C/1298A haplotype who experienced toxicity was greater than the proportion of those with 677C/1298C who did (P=0.032, odds ratio=2.085, 95% confidence interval 1.058-4.106). In this study, MTHFR polymorphisms were associated with MTX toxicities in Korean patients with RA. Further study for association of MTHFR polymorphisms with MTX toxicities should be needed in larger RA population.

Role of Methylenetetrahydrofolate Reductase Gene Polymorphisms (C677T, A1298C, and G1793A) in the Development of Early Onset Vasculogenic Erectile Dysfunction

The methylenetetrahydrofolate reductase (MTHFR) gene plays a key role in the metabolism of folate and homocysteine (Hcy) and its mutations have been associated with high serum Hcy level. Elevated serum Hcy has been linked to impaired endothelial function and occlusive vascular disease. We studied the association among the different genotypes of all three MTHFR polymorphisms (C677T, A1298C, and G1793A) and the risk of early-onset vasculogenic erectile dysfunction (VED). We performed a case-control study of 114 men with early-onset VED and 228 age-matched controls. Genotyping of MTHFR gene polymorphisms was performed using polymerase chain reaction restriction fragment length polymorphism (PCR-RLFP) technique. We also measured plasma lipids, Hcy, folate, and vitamin B12 levels. Patients with early-onset VED had higher serum Hcy levels (12.29 ± 2.32 vs. 9.82 ± 2.35 μmol/L, p = 0.001) and higher prevalence of 677TT homozygocity compared to controls (15.8% vs. 11.4%, p = 0.01). Serum Hcy concentration was significantly higher in individuals with 677TT, 1298CC, and 1793GG genotypes. Subgroup analysis according to severity of ED (mild, moderate, and severe) showed that patients with severe VED had higher serum Hcy levels compared to patients with mild VED (13.48 ± 2.51 vs. 11.21 ± 2.32 μmol/L, p = 0.001). Odds ratio seems to demonstrate that individuals with the MTHFR 677TT genotype and the 677TT + 1298AC combined genotype had a 3.16- and 3.89-fold increased risk for developing VED, suggesting a possible association of MTHFR polymorphisms with the risk of early-onset VED.

Association Between the Methylenetetrahydrofolate Reductase Polymorphisms and Risk of Acute Lymphoblastic Leukemia in Serbian Children

Methylenetetrahydrofolate reductase (MTHFR) regulates the metabolism of folate and methionine, essential components of DNA synthesis and methylation. Polymorphisms in the MTHFR gene have been associated with susceptibility to some types of cancer. We investigated a possible association of MTHFR polymorphisms (677C>T and 1298A>C) and increased risk for acute lymphoblastic leukemia in 78 affected children. The frequencies of both MTHFR 677 genotypes and alleles were significantly different between patients and controls. A significant association between CT/TT individuals and reduced risk of acute lymphoblastic leukemia was found. The odds ratios were 0.53 (95% confidence interval, 032-0.89) and 0.30 (95% confidence interval, 0.12-0.81). Polymorphism 1298 did not show statistical difference between patients and controls.

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

To analyze the association of methylenetetrahydrofolate reductase polymorphisms (MTHFR-677 and MTHFR-1298) with occlusive artery disease and deep venous thrombosis in Macedonians. 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. 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. 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.

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

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.

Association of Methylenetetrahydrofolate Reductase Polymorphism and the Risk of Squamous Cell Carcinoma in Renal Transplant Patients

The relative risk of developing cutaneous squamous cell carcinoma (SCC) is significantly increased after organ transplantation. We investigated the genetic association of SCC in two pathways associated with cancer risks, with the potential for modification by vitamin supplementation. A total of 367 renal transplant recipients (117 with SCC and 250 without any skin cancer) were genotyped for key polymorphisms in the folate pathway (methylene tetrahydrofolate reductase; MTHFR:C677T), and the vitamin D pathway (vitamin D receptor: Intron8G/T;). Individuals carrying the MTHFR 677T allele had a marked increase in risk of SCC (adjusted odds ratio=2.54, P=0.002, after adjustment for age, ender, skin type, sun exposure score, and immunosuppression duration; lower 95% confidence boundary odds ratio of 1.41). In contrast, vitamin D receptor polymorphisms were not significantly associated. Folate-sensitive pathways may play a critical role in the elevated rate of SCC in renal transplant recipients.

No evidence of association of methylenetetrahydrofolate reductase polymorphism with occurrence of second neoplasms after treatment of childhood leukemia

Methylenetetrahydrofolate reductase (MTHFR) polymorphisms have been associated not only with the risk for acute lymphoblastic leukemia (ALL) in adults and children, but also with increased methotrexate toxicity. The present study aimed to investigate whether MTHFR polymorphisms modify the risk for development of secondary malignancies in children treated for ALL with protocols that included high-dose methotrexate. MTHFR genotypes were determined in DNA samples isolated from archived bone marrow smears of 15 patients with a second malignancy and a matched control group of 30 patients who did not developed a second malignancy after the treatment for ALL. The frequencies of MTHFR C677T and A1298C genotypes in all patients were: C677T: CC 40%, CT 46.7% and TT 13.3% and A1298C: AA 46.7%, AC 44.4% and CC 8.9%. The relative risk for second malignancy was not significantly increased in ALL patients having at least one polymorphic C667T [odds ratio (OR) 1.51; 95% confidence interval (CI) 0.43-5.31] or one polymorphic A1298C allele (OR 1; 95% CI 0.29?-?3.46). Our study suggests that MTHFR polymorphisms are not associated with increased risk of second cancer in children treated with high-dose methotrexate.