The MTHFR CT polymorphism confers a high risk for stroke in both homozygous and heterozygous T allele carriers with Type 2 diabetes

Association of methylenetetrahydrofolate reductase (MTHFR) rs1801133 (677C>T) gene polymorphism with ischemic stroke risk in different populations: An updated meta-analysis

Background: Recently, increasing evidence has implicated methylenetetrahydrofolate reductase (MTHFR) gene mutation as a risk factor for ischemic stroke (IS) in the general population. However, studies have been inconclusive and lack evidence on specific populations. We aim to determine whether the rs1801133 (NC_000001.11 (MTHFR):g. 677C>T (p.Ala222Val) variant, we termed as MTHFR rs1801133 (677 C>T), is linked to an increased risk of IS in different age groups and ancestry groups. Methods: The literature relevant to our study was found by searching the PubMed, Cochrane Library, Web of Science, EMBASE, and CNKI databases. A random effect model analysis was used to calculate the pooled odds ratio (OR) and 95% confidence interval (CI) to evaluate any possible association. We conducted a subgroup analysis based on the age and ancestry groups of the included populations. Results: As of March 2022, 1,925 citations had been identified in electronic databases, of which 96 studies involving 34,814 subjects met our eligibility criteria. A strong link was found between IS and the MTHFR gene rs1801133 (677C>T) polymorphism in all genetic models [dominant genetic model (OR = 1.47; 95%CI = 1.33-1.61; p < 0.001), recessive genetic model (OR = 1.52; 95%CI = 1.36-1.71; p < 0.001), heterozygous model (OR = 1.36; 95%CI = 1.24-1.48; p < 0.001), homozygous model (OR = 1.82; 95%CI = 1.58-2.11; p < 0.001), and T allelic genetic model (OR = 1.37; 95%CI = 1.27-1.48; p < 0.001)]. Further subgroup analyses indicated that the MTHFR rs1801133 (677C>T) variant may increase the risk of IS in Asian, Hispanic, or Latin population, middle-aged, and elderly populations (p < 0.001). Conclusion: Our results implied that mutation of the T allele of MTHFR rs1801133 (677C>T) could be a risk factor for IS. A significant association was found among Asian, Hispanic, or Latin population, middle-aged, and elderly people.

Relationship of Methylenetetrahydrofolate Reductase (MTHFR) C677T Variation With Susceptibility of Patients With Ischemic Stroke: A Meta-Analysis

Discovery and validation of genetic factors for multifactorial and polygenic disorders like stroke are needed to make progress in precision medicine. Although some traditional risk factors for stroke have been identified, they do not fully explain the pathophysiological mechanism of ischemic stroke. The research of genetic risk factors is becoming increasingly relevant in the understanding of stroke mechanisms and the finding of population-specific therapeutic targets. The methylenetetrahydrofolate reductase (MTHFR) gene is involved in homocysteine metabolism, and a high homocysteine level is a risk factor for stroke. Using a meta-analysis technique, we investigated the link between the MTHFR C677T gene polymorphism and the risk of ischemic stroke.

We used the electronic databases PubMed, Medline, Embase, and Google Scholar to find articles in the Journal of Stroke. If heterogeneity was more than 50%, pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random-effects model; otherwise, a fixed-effects model was used.

A total of 67 case-control studies with 17,704 cases and 21,981 controls met our inclusion criteria. The Asian population was represented by 41 studies, whereas the Caucasian population was represented by 26. Under the recessive model, a gene polymorphism at the 677 location of the MTHFR gene is related to an elevated risk of ischemic stroke (OR: 1.29, 95% CI: 1.22-1.37, P < 0.001).

People who have the MTHFR C677T gene polymorphism have a greater risk of stroke than people who do not.

Association of the methylenetetrahydrofolate reductase (MTHFR) gene variant C677T with serum homocysteine levels and the severity of ischaemic stroke: a case-control study in the southwest of China

OBJECTIVE

To determine whether the methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism is linked to the risk of ischaemic stroke and circulating homocysteine (Hcy) levels in a Chinese population.

METHODS

This case-control study recruited angiogram-diagnosed patients with ischaemic stroke and healthy control subjects. The plasma Hcy concentrations were measured and the MTHFR C677T gene polymorphism was genotyped. The National Institutes of Health Stroke Scale (NIHSS) was used to assess the severity of the ischaemic stroke.

RESULTS

This study recruited 198 patients with ischaemic stroke and 168 controls. The TT genotype conferred a higher risk for ischaemic stroke than the CC genotype (odds ratio of 3.563; 95% confidence interval [CI] 1.412, 4.350). The T allele was the predisposing allele for ischaemic stroke. Hcy had an area under the receiver operating characteristic (ROC) curve of 0.624 (95% CI 0.530, 0.758). The ROC for Hcy demonstrated its usefulness in predicting ischaemic stroke. Hcy levels were not associated with ischaemic stroke severity as measured by the NIHSS.

CONCLUSION

The MTHFR C677T gene polymorphism affects circulating Hcy levels. The MTHFR C677T gene polymorphism and hyperhomocysteinaemia may play important roles in predicting the risk of ischaemic stroke.

MTHFR Gene Polymorphisms and Cardiovascular Risk Factors, Clinical-Imagistic Features and Outcome in Cerebral Venous Sinus Thrombosis

Cerebral venous sinus thrombosis (CVST) as a severe neurological emergency, is represented by variable conditions in its clinic presentation, onset, risk factors, neuroimagistic features and outcome. The genetic polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C was associated with CVST. We aimed to characterize the prevalence of MTHFR gene polymorphisms associated with cardiovascular risk factors in the group of patients with CVST. Also, we studied additional causes associated with CVST including local infections, general infections, obstetric causes (pregnancy, puerperium) and head injury. This is a retrospective study including 114 patients which referred to our hospital between February 2012-February 2020. The protocol included demographic (age, sex), clinical, neuroimagistic features, paraclinic (genetic polymorphism of MTHFR, factor V G1691A-Leiden, prothrombin G20210A, PAI-1 675 4G/5G; Homocysteine level, the lipid profile, blood glucose and Glycohemoglobin HbA1c, high- sensitive C- reactive protein- hsCRP) data, as well as treatment and outcome. The mean age was 37.55 years with a female predominance (65.79%). In the first group of patients with inherited thrombophilia (60 cases; 52.63%) we found genetic mutation includes MTHFR C677T (38.59%) and A1298C (14.03%), factor V G1691A- Leiden (15.78%), prothrombin G20210A (2.63%), PAI-1 675 4G/5G (42.98%), and hyperhomocysteinemia (35.08%). At the second group with other etiology of CVST, except thrombophilia, we included 54 patients (47.36%). The most common sites of thrombosis were the superior sagittal sinus (52.63%). Headache was the most common symptom (91.22%) and seizures were the main clinical presentation (54.38%). The MTHFR polymorphism was significantly correlated with higher total cholesterol (TC) (p = 0.023), low- density lipoprotein cholesterol (LDL) (p = 0.008), homocysteine level (tHcy) (p < 0.001). Inside the first group with MTHFR polymorphism we have found a significant difference between the levels of homocysteine at the patients with MTHFR C677T versus MTHFR A1298C polymorphism (p < 0.001). The high-sensitive C-reactive protein (hsCRP) was increased in both groups of patients, but the level was much higher in the second group (p = 0.046). Mortality rate was of 2.63%. Demographic, clinical and neuroimagistic presentation of CVST in our study was similar with other studies on the matter, with a high frequency of thrombophilia causes. MTHFR gene polymorphisms (C677T and A1298C) are increased in prevalence in CVST. PAI-1 675 4G/5G gene mutation seems to be involved in CVST etiology. Plasma C-reactive protein level and hyperhomocysteinemia should be considered as a prognostic factor in CVST.

Compound heterozygous MTHFR (C677T and A1298C) variants and anterior STEMI: cause or bystander?

We present the case of a 40-year-old female patient with ST-segment elevation myocardial infarction successfully treated with a primary percutaneous coronary intervention. Thrombophilia testing revealed compound heterozygous MTHFR (C677T and A1298C) variants. We searched the literature for myocardial infarction in the setting of MTHFR polymorphisms and the possible pathophysiologic mechanisms. In young patients presenting with a thrombotic event, screening for thrombophilia could be beneficial for identification of etiology.

MTHFR Gene Polymorphisms Prevalence and Cardiovascular Risk Factors Involved in Cardioembolic Stroke Type and Severity

Background: Cardioembolic stroke (CES), generally known as the most severe subtype of ischemic stroke, is related to many factors, including diabetes mellitus (DM), hypertension (HTN), smoking, hyperlipidemia and atrial fibrillation (AF). Genetic mutations of the methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C have been recently associated with ischemic stroke. The purpose of this study was to analyze the prevalence of MTHFR gene polymorphisms correlated with cardiovascular risk factors in a selected population of patients with CES due to non-valvular AF (NVAF). Methods: This cross-sectional study was performed on 67 consecutive patients with acute cardioembolic stroke admitted to our hospital. The protocol included general physical examination, neurological clinical status and stroke severity evaluation, imagistic evaluation and genetic testing of MTHFRC677T and A1298C polymorphisms. Results: The prevalence of MTHFR polymorphisms in the study population was 38.2% for C677T and 40.3% for A1298C. The C677T mutation was significantly correlated with increased diastolic blood pressure (DBP) values (p = 0.007), higher total cholesterol (TC) (p = 0.003), low-density lipoprotein cholesterol (LDLc) (p = 0.003) and triglycerides (TGL) (p = 0.001), increased high-sensitive C-reactive protein (hsCRP) values (p = 0.015), HbA1c (p = 0.004) and left ventricle ejection fraction (LVEF) (p = 0.047) and lower high-density lipoprotein cholesterol (HDLc) (p < 0.001) compared to patients without this genetic variant. This genetic profile also included significantly higher CHA₂DS₂VASC (p = 0.029) and HASBLED (Hypertension, Abnormal liver/renal function, Stroke, Bleeding, Labile INR, Elderly age(>65 years), Drug/Alcohol usage history/Medication usage with bleeding predisposition) (p = 0.025) scores. Stroke severity in patients with MTHFRA1298C mutation was significantly increased when applying National Institutes of Health Stroke Scale (NIHSS) (p = 0.006) and modified Rankin scale (mRS) (p = 0.020) scores. The presence of A1298C mutation as a dependent variable was associated with significantly higher TGL values (odds ratio (OR) = 2.983, 95%CI = (1.972, 7.994)). Conclusions: The results obtained in this study demonstrate that MTHFR gene polymorphisms have a high prevalence in an NVAF cardioembolic stroke population. Moreover, an association between C677T mutation and stroke severity was highlighted. The C677T mutation in patients with NVAF was correlated with a higher incidence of cardiovascular comorbidities (hypertension HTN, heart failure (HF), dyslipidemia, type II diabetes mellitus (T2DM) with high HbA1c and increased inflammatory state). The A1298CMTHFR gene mutation was associated with a higher incidence of previous lacunar stroke and stroke recurrence rate, while dyslipidemia was the main cardiovascular comorbidity in this category.

Recurrent Myocardial Infarction Despite Normal C-reactive Protein in a Patient with Behcet's Disease and Compound Heterozygous Methylenetetrahydrofolate Reductase (MTHFR) Mutations (C677T and A1298C)

A 39-year-old diabetic female with Behcet’s disease presented with acute inferior wall myocardial infarction and underwent successful angioplasty of the occluded circumflex artery with a bare-metal stent (balancing increased the bleeding risk with Behcet's). Other coronary vessels were free of obstructive atherosclerosis. Optimal coronary artery disease (CAD) therapy was commenced, and Behcet’s disease treatment was intensified with the normalization of C-reactive protein. Two years later, she presented with an acute left anterior descending artery occlusion that was managed with a drug-eluting stent this time. There was no evidence of diffuse atherosclerosis on coronary angiogram or coronary calcifications on the chest computed tomography (CT) scan. Compound heterozygous methylenetetrahydrofolate reductase (MTHFR) mutations (C677T and A1298C) and high-normal plasma homocysteine were detected. With the long-term continuation of dual anti-platelet, lipid-lowering, immunosuppressive, and folic-acid therapies, she did not have cardiac events during the three-year follow-up. This is the first report of recurrent thrombotic acute coronary syndrome (ACS) in a patient with diabetes, compound heterozygous MTHFR mutations, Behcet’s disease with normal C-reactive protein (CRP), and no evidence of diffuse coronary artery disease.

Association between end-stage diabetic nephropathy and MTHFR (C677T and A1298C) gene polymorphisms

AIM

Methylenetetrahydrofolate reductase (MTHFR) is a regulatory enzyme of homocysteine metabolism. The C677T and A1298C polymorphism of the MTHFR gene has been reported to be associated with elevated plasma homocysteine in patients with Diabetic nephropathy. This study aimed to investigate the influence of the C677T and A1298C polymorphisms on the progression chronic kidney disease in diabetic nephropathy of south Indian population.

METHODS

We genotyped 145 DN cases and 100 controls for the C677T and A1298C polymorphisms using PCR-RFLP based protocols, and all diabetic nephropathy cases divided into two groups based on CKD stages: 60 DN cases were early stage (CKD1 to CKD3) and 85 DN cases were advanced stage (CKD4 and CKD5). Association χ² and univariate analysis were performed.

RESULTS

The C677T (OR = 4.2; 95% CI = 2.31-7.64 and P = 0.001) and A1298C (OR = 2.8; 95% CI = 1.05-7.57 and P = 0.033) polymorphism was shown that the significant association between the cases and control. Furthermore, the MTHFR gene polymorphism C677T (OR = 2.48; 95% CI = 1.25-4.9 and P = 0.008) was observed that the significant contribution of the progression of CKD in DN.

CONCLUSION

These findings suggest that the C677T and A1298C polymorphism of MTHFR gene was associated with diabetic nephropathy in a south Indian population. Furthermore, the present study provides evidence that the C677T polymorphism was associated with CKD progression in DN.

Effect of folic acid supplementation on nerve conduction velocity in diabetic polyneuropathy patients

OBJECTIVES

In diabetic polyneuropathy (DPN) patients, the effect of folic acid and homocysteine has been related to components of nerve conduction velocity (NCV). The objective of this study was to determine the effect of folic acid supplementation on NCV in DPN patients.

METHODS

Patients were randomized to receive either 1 mg of folic acid (n = 40) or placebo (n = 40) for 16 weeks. Blood samples were collected to assess serum folic acid and homocysteine concentrations, and NCV was performed for assessment of diabetic neuropathy.

RESULTS

At 16 weeks, in the supplemented group, serum levels of folic acid (p < 0.001) increased, homocysteine concentrations decreased (p < 0.001), with no change in serum vitamin B12 levels. There was a significant increase in sensory sural amplitude (p < 0.001), and components of motor nerves, including amplitude (p = 0.001) and velocity (p < 0.001), but decreased onset latency of peroneal (p = 0.019) and tibial (p = 0.011) motor nerves.

CONCLUSION

Our data suggest that supplementation with 1 mg of folic acid for 16 weeks may be useful for enhancing NCV in DPN patients.

Unambiguous detection of multiple TP53 gene mutations in AAN-associated urothelial cancer in Belgium using laser capture microdissection

In the Balkan and Taiwan, the relationship between exposure to aristolochic acid and risk of urothelial neoplasms was inferred from the A>T genetic hallmark in TP53 gene from malignant cells. This study aimed to characterize the TP53 mutational spectrum in urothelial cancers consecutive to Aristolochic Acid Nephropathy in Belgium. Serial frozen tumor sections from female patients (n = 5) exposed to aristolochic acid during weight-loss regimen were alternatively used either for p53 immunostaining or laser microdissection. Tissue areas with at least 60% p53-positive nuclei were selected for microdissecting sections according to p53-positive matching areas. All areas appeared to be carcinoma in situ. After DNA extraction, mutations in the TP53 hot spot region (exons 5–8) were identified using nested-PCR and sequencing. False-negative controls consisted in microdissecting fresh-frozen tumor tissues both from a patient with a Li-Fraumeni syndrome who carried a p53 constitutional mutation, and from KRas mutated adenocarcinomas. To rule out false-positive results potentially generated by microdissection and nested-PCR, a phenacetin-associated urothelial carcinoma and normal fresh ureteral tissues (n = 4) were processed with high laser power. No unexpected results being identified, molecular analysis was pursued on malignant tissues, showing at least one mutation in all (six different mutations in two) patients, with 13/16 exonic (nonsense, 2; missense, 11) and 3/16 intronic (one splice site) mutations. They were distributed as transitions (n = 7) or transversions (n = 9), with an equal prevalence of A>T and G>T (3/16 each). While current results are in line with A>T prevalence previously reported in Balkan and Taiwan studies, they also demonstrate that multiple mutations in the TP53 hot spot region and a high frequency of G>T transversion appear as a complementary signature reflecting the toxicity of a cumulative dose of aristolochic acid ingested over a short period of time.

Does the MTHFR C677T gene polymorphism indicate cardiovascular disease risk in type 2 diabetes mellitus patients?

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.

The effect of MTHFR C677T polymorphism on type 2 diabetes mellitus with vascular complications in Chinese Han population: a meta-analysis

Methylenetetrahydrofolate reductase plays an important role in folate metabolism. Individuals who are type 2 diabetes mellitus have greatest risk for the development of vascular complications. The results of studies which assessed the association between MTHFR C677T polymorphism and T2DM with vascular complications were inconsistent in the Chinese Han population. The purpose of this meta-analysis was to assess the associations between MTHFR C677T polymorphism and T2DM with vascular complications in the Chinese Han population. We collected all relevant articles on MTHFR C677T polymorphisms and T2DM with vascular complications in the Chinese Han population in multiple electronic databases which were searched to December 2013. Fixed-effects and random-effects meta-analyses were performed to assess the odds ratios (ORs). Stratified Analysis, sensitivity Analysis and publication bias were examined. A total of 1984 diabetic patients with vascular complications and 1703 single diabetic patients were found in meta-analysis. There was a significant association between MTHFR C677T polymorphisms and T2DM with vascular complications under recessive genetic model, dominant genetic model, homozygous genetic model, heterozygous genetic model and allele comparison. Sensitivity analysis indicated that the overall result was dependable. Our meta-analysis suggests the MTHFR C677T polymorphisms is associated with T2DM with vascular complications in the Chinese Han population.

Association of homocysteine with type 2 diabetes: a meta-analysis implementing Mendelian randomization approach

BACKGROUND

We tested the hypothesis that elevated homocysteine (Hcy) level is causally associated with increased risk of type 2 diabetes mellitus (T2DM).

RESULTS

The meta-analysis and Mendelian randomization analysis were performed among 4011 cases and 4303 controls. The absolute pooled mean Hcy concentration in subjects with MTHFR 677TT was 5.55 μmol/L (95% CI, 1.33 to 9.77) greater than that in subjects with MTHFR 677CC in T2DM. Overall, the T allele of the MTHFR 677 C > T conferred a greater risk for T2DM [Random effect (RE) OR = 1.31(1.17-1.64), I² = 41.0%, p = 0.055]. The random effect (RE) pooled OR associated with T2DM for MTHFR 677TT relative to the 677CC was [RE OR = 1.38(1.18-1.62)]. The fixed-effect pooled OR of the association for the MTHFR 677 TT vs CT was 1.29 (95% CI, 1.09-1.51). MTHFR 677 TT showed a significantly higher risk for T2DM compared with MTHFR 677 CC + CT [Fixed effect (FE) OR = 1.32(1.14-1.54), I² = 0.0%, p = 0.686]. The absolute pooled mean Hcy concentration in individuals with T2DM was 0.94 μmol/L (95% CI, 0.40-1.48) greater than that in control subjects. The estimated causal OR associated with T2DM was 1.29 for 5 μmol/L increment in Hcy.

CONCLUSIONS

Our findings provided strong evidence on the causal association of Hcy level with the development of T2DM.

The Influence of Stroke Risk Factors and Comorbidities on Assessment of Stroke Therapies in Humans and Animals

The main driving force behind the assessment of novel pharmacological agents in animal models of stroke is to deliver new drugs to treat the human disease rather than to increase knowledge of stroke pathophysiology. There are numerous animal models of the ischaemic process and it appears that the same processes operate in humans. Yet, despite these similarities, the drugs that appear effective in animal models have not worked in clinical trials. To date, tissue plasminogen activator is the only drug that has been successfully used at the bedside in hyperacute stroke management. Several reasons have been put forth to explain this, but the failure to consider comorbidities and risk factors common in older people is an important one. In this article, we review the impact of the risk factors most studied in animal models of acute stroke and highlight the parallels with human stroke, and, where possible, their influence on evaluation of therapeutic strategies.

Nutrigenetic impact of daily folate intake on plasma homocysteine and folate levels in patients with different methylenetetrahydrofolate reductase genotypes

BACKGROUND

Elevated plasma homocysteine level is associated with coronary artery disease (CAD). Homozygosity for the C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene is typically but inconsistently associated with hyperhomocysteinemia. We examined the impact of daily intake of folate, a co-factor in homocysteine metabolism, on plasma homocysteine and folate levels in CAD patients in relation with MTHFR genotypes.

METHODS

Daily folate intake was assessed from 3-day food records in 99 patients with CAD: 35 with the T/T (homozygous mutant) genotype and 64 with the C/C or C/T (non-T/T) genotypes.

RESULTS

Patients with the T/T genotype had higher fasting plasma homocysteine levels (18.4±1.9 vs. 12.6±0.6 μmol/l, P=0.01) and lower plasma folate levels (17.8±1.7 vs. 20.8±1.0 nmol/l, P=0.02). There were no differences between the genotype groups in energy-adjusted folate intake. In patients with the non-T/T genotypes, higher folate intake was associated with higher plasma folate levels and lower plasma homocysteine levels. In T/T homozygotes this association was weaker. Linear regression analysis showed that folate intake, the MTHFR genotype, plasma vitamin B12 levels, and the interaction between plasma folate level and MTHFR genotype, predicted homocysteine elevation. (folate intake, P=0.04, MTHFR genotype, P=0.03, plasma folate, P=0.02, and plasma B12 level, P=0.004). The model explained only 29% of the variance in log-transformed plasma homocysteine levels.

CONCLUSION

T/T homozygotes are more sensitive to the combination of low folate intake, low plasma folate and vitamin B12 level, than patients with non-T/T genotypes. The variability in plasma homocysteine in T/T homozygotes is only partly explained by these variables.

The genetics of vascular complications in diabetes mellitus

Prospective identification of which individuals with diabetes mellitus (DM) are at greatest risk for developing cardiovascular disease (CVD) complications would have considerable public health importance by allowing the allocation of limited resources to be focused on those individuals who would most benefit from aggressive intervention. Over the past 20 years genetic disease association studies have demonstrated that polymorphisms at specific genetic loci may identify those individuals at greatest risk for developing CVD in the setting of DM. This article reviews the evidence accumulated to date on four polymorphic loci with the aim of explaining how these polymorphisms modify the risk for CVD in DM by modifying the functional activity of a specific gene. Use of the knowledge of these genetic differences among individuals in targeting drug therapy (pharmacogenomics) is also discussed.

Methylenetetrahydrofolate reductase C677T gene polymorphism in Turkish patients with polycystic ovary syndrome

Higher Levels of Hcy are associated with several clinical conditions, among them non-insulin-dependent diabetes mellitus, endometrial dysplasia and hypertension with insulin resistance, and polycystic ovary syndrome. The purpose of this study was to investigate the serum homocystein levels and other metabolic parameters in relationship with the MTHFR C677T gene polymorphism in patients with PCOS. Our study included 86 young women with PCOS constituting the study group and 70 healthy women constituting the control group. Homocystein levels, metabolic, and hormonal parameters were measured, and genetic analysis of the MTHFR C677T gene polymorphism was performed in all the subjects. A statistically significant difference was observed in mean homocystein levels between patients with PCOS when compared to the control group. The MTHFR 677 CC genotypes had significantly higher proportions in the control group compared to the PCOS patients (χ(2) = 21.381, P < 0.001). Our data show that homocystein levels were higher than normal subjects in patients with PCOS and that the MTHFR C677T gene polymorphism does not influence homocystein levels of patients with PCOS.

A1298C polymorphism in the MTHFR gene predisposes to cardiovascular risk in rheumatoid arthritis

INTRODUCTION

We determined the contribution of the methylene tetrahydrofolate reductase (MTHFR) 677 C>T and 1298 A>C gene polymorphisms to the susceptibility to rheumatoid arthritis (RA). We also assessed whether these two MTHFR gene polymorphisms may be implicated in the development of cardiovascular (CV) events and subclinical atherosclerosis manifested by the presence of endothelial dysfunction, in a series of Spanish patients with RA.

METHODS

Six hundred and twelve patients fulfilling the 1987 American College of Rheumatology classification criteria for RA, seen at the rheumatology outpatient clinics of Hospital Xeral-Calde, Lugo and Hospital San Carlos, Madrid, were studied. Patients and controls (n = 865) were genotyped using predesigned TaqMan SNP genotyping assays.

RESULTS

No significant differences in allele or genotype frequencies for the MTHFR gene polymorphisms between RA patients and controls were found. Also, no association between the MTHFR 677 C>T polymorphism and CV events or endothelial dysfunction was observed. However, the MTHFR 1298 allele C frequency was increased in patients with CV events after 5 years (38.7% versus 30.3%; odds ratio = 1.45; 95% confidence interval = 1.00 to 2.10; P = 0.04) and 10 years (42.2% versus 31.0%; odds ratio = 1.62; 95% confidence interval = 1.08 to 2.43; P = 0.01) follow up. Moreover, patients carrying the MTHFR 1298 AC and CC genotypes had a significantly decreased flow-mediated endothelium-dependent vasodilatation (4.3 +/- 3.9%) compared with those carrying the MTHFR 1298 AA genotype (6.5 +/- 4.4%) (P = 0.005).

CONCLUSIONS

Our results show that the MTHFR 1298 A>C gene polymorphism confers an increased risk for subclinical atherosclerosis and CV events in patients with RA.

Genetic risk factors for arterial ischemic stroke in children: a possible MTHFR and eNOS gene-gene interplay?

In order to investigate the influence of genetic factors in childhood stroke, we compared the distributions of mutations/ polymorphisms affecting hemostasis and/or endothelial function (factor V [FV] Leiden, factor II [FII] G20210A, methylenetetrahydrofolate reductase [MTHFR] C677T, angiotensin-converting enzyme [ACE] insertion/deletion [ID], and endothelial nitric oxide synthase [eNOS] G894T) among children with stroke and controls. A total number of 26 children with arterial ischemic stroke and a control group of 50 healthy children were included in the study. No statistically significant differences in allelic and genotypic distribution were detected in comparisons between groups. However, when combined genotypes were analyzed, statistical significance was observed for the association of MTHFR CT and eNOS TT gene variants. The results of our study suggest that this genotype combination represents a risk factor of 7.2 (P = .017) for arterial ischemic stroke in children.

Association of vitamin B12, folate and homocysteine with functional and pathological characteristics of the elderly in a mountainous village in Sicily

Homocysteine is associated with age, folate and vitamin B

Subjects (n=280) were examined after door-to-door recruitment using interview, physician examination and laboratory tests.

A total of 19.3% of the population had a low blood level of folate (<7 nmol/L) and 3.2% had low vitamin B

The prevalence of deficits in folate and vitamin B

Clin Chem Lab Med 2007;45:136–42.