Methylenetetrahydrofolate Reductase C677T Mutation Research Articles

Inherited risk factors in low-risk venous thromboembolism in patients under 45 years.

Venous thromboembolism (VTE) is a complex disease and an important preventable cause of morbidity and mortality today. Many genetic and acquired factors contribute to its aetiology. The aim of the present study is to investigate the incidence of inherited risk factors for thrombophilia in patients under 45 years of age who presented with VTE without having a major acquired risk factor. Of 96 VTE patients who presented to our outpatient department between February 2012 and November 2013, 58 were considered eligible for the study. Blood samples taken for thrombophilia testing were investigated in a molecular genetics and diagnosis laboratory. These data were collected prospectively and analysed retrospectively. The mean age of patients in our study was 39.12 ± 2.1 years. Of the 58 patients, 30 had factor V Leiden mutation (5 homozygous, 25 heterozygous), 16 had prothrombin gene mutation, 24 had methylenetetrahydrofolate reductase C677T mutation (5 homozygous, 19 heterozygous), 18 had protein C deficiency, 17 had protein S deficiency, 14 had antithrombin III deficiency and 13 had hyperhomocysteinaemia. We observed that at least one inherited risk factor was present in most of the patients with VTE (n = 45), a finding that was compatible with those of previous studies. Inherited risk factors are common among patients who present with VTE but have no major acquired risk factors. We conclude that these patients should be further evaluated for evidence of molecular risk factors.

Methylenetetrahydrofolate reductase C677T gene mutation and hyperhomocysteinemia in Budd-Chiari syndrome and portal vein thrombosis: A systematic review and meta-analysis of observational studies.

A systematic review and meta-analysis were conducted to explore the role of the methylenetetrahydrofolate reductase (MTHFR) C677T gene mutation and hyperhomocysteinemia in patients with Budd-Chiari syndrome (BCS) and portal vein thrombosis (PVT). PubMed, EMBASE, Cochrane Library and ScienceDirect databases were searched. Eligible studies should compare the prevalence of the MTHFR C677T mutation or hyperhomocysteinemia or the homocysteine levels between BCS or non-cirrhotic PVT patients and healthy controls or between cirrhotic patients with and without PVT. A pooled odds ratio or weighted mean difference with 95% confidence interval was calculated. Of the 484 articles retrieved, 20 were included. BCS and non-cirrhotic PVT patients had a higher prevalence of homozygous MTHFR mutation than healthy controls. The difference was statistically significant in BCS patients, but not in non-cirrhotic PVT patients. BCS and non-cirrhotic PVT patients had a significantly higher prevalence of hyperhomocysteinemia and homocysteine level than healthy controls. Cirrhotic patients with PVT had a significantly higher prevalence of homozygous MTHFR mutation than those without PVT. However, the association between homocysteine level and PVT in cirrhotic patients was inconsistent among three studies. Homozygous MTHFR mutation and hyperhomocysteinemia may be associated with the occurrence of BCS and non-cirrhotic PVT. In addition, homozygous MTHFR mutation may increase the risk of PVT in cirrhotic patients. However, the current evidence failed to support the association of hyperhomocysteinemia with PVT in cirrhotic patients.

Thrombophilia in Patients with Retinal Vein Occlusion: A Retrospective Analysis

Background: To assess the prevalence of thrombophilia in patients with central (CRVO) and branch retinal vein occlusion (BRVO). Methods: In 139 patients with CRVO (n = 88) and BRVO (n = 51) and in 40 healthy controls factor VIII, fibrinogen, antithrombin III, protein C, protein S, activated protein C resistance, anticardiolipin antibodies (ACA), homocysteine, factor V Leiden, prothrombin G20210A and methylene tetrahydrofolate reductase (MTHFR) C677T mutation were assessed retrospectively. Results: Elevated factor VIII activity and the homozygous MTHFR C677T mutation were significantly more often found in CRVO and BRVO cases compared to controls. Age-, gender- and C-reactive protein-adjusted logistic regression analysis did not show a significant additive effect of elevated factor VIII activity on the risk of developing CRVO/BRVO. Elevated fibrinogen levels and ACA were significantly more often found in CRVO than amongst controls. No significant differences were found concerning the remaining variables. Conclusions: We suggest elevated fibrinogen levels, ACA and the homozygous MTHFR C677T mutation as potential risk factors for CRVO/BRVO.

Hyperhomocysteinaemia, low folate concentrations and MTHFR C677T mutation in abdominal aortic aneurysm.

Homocysteine (Hcy) has been implicated in abdominal aortic aneurysm (AAA). However, the association of Hcy, vitamin B12, and folate in patients with AAA has not been studied in China. This study was conducted with the aim to evaluate the relationship of vitamin B12, folic acid, and Hcy levels in AAA. 463 patients who had AAA were included in this study. 463 control subjects were age- and sex-matched with the patients. In all of the subjects, we evaluated total plasma levels Hcy, vitamin B12, folic acid and the distribution of the C677T methylenetetrahydrofolate reductase (MTHFR) gene mutation. The mean plasma Hcy levels were significantly higher in patients with AAA compared with controls (18.37 ± 6.97 vs. 12.89 ± 4.08 μmol/L, P < 0.001). The frequency of homozygous (TT) genotype in MTHFR C677T mutation was significantly higher in patients with AAA than that in control subjects (19.4 % vs. 11.9 %, P = 0.002). The fasting Hcy correlated negatively with folate (AAA: r = - 0.311, P < 0.01; r = - 0.348, P < 0.01). The aneurysm size was significantly greater (P < 0.001) in patients with hyperhomocysteinemia than that in patients with normal Hcy plasma levels. The size of the AAA had a linear correlation with the plasma Hcy level (r = 0.286; P< 0.001). Serum folate deficiency and hyperhomocysteinemia were associated with an increased risk of AAA in Northeast China. The homozygous (TT) genotype of MTHFR gene mutation may be a crucial hereditary risk factor in AAA.

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

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.

Plasma Homocysteine in Patients with Retinal Vein Occlusion

To evaluate total plasma homocysteine (HCY) during fasting and post methionine load test (MLT), serum folate, serum vitamin B12, and methylenetetrahydrofolate reductase (MTHFR) mutation in patients with retinal vein occlusion (RVO) and to examine the association between these risk factors and 2 subtypes of RVO: central (CRVO) and branch (BRVO). This case-control study included 91 Italian patients presenting a first RVO and 71 healthy subjects, matched by age, without history of thromboembolic diseases, glaucoma, or malignancy. Homocysteine fasting and after MLT, serum folate level, serum vitamin B12 level, and other laboratory tests were assessed. Genetic analysis for the C677T MTHFR mutation was performed. Multivariate logistic regression analysis indicated that hypertension (odds ratio [OR] 2.63; 95% confidence interval [CI] 1.30-5.30; p = 0.007), higher values of fasting HCY (OR 1.16; 95% CI 1.01-1.33; p = 0.03), and low concentrations of vitamin B12 (OR 0.99; 95% CI 0.995-0.999; p = 0.01) were independently correlated with RVO. Moreover, the main determinants for CRVO risk were hypertension (OR 2.46; 95% CI 1.06-5.72; p = 0.04), high values of fasting HCY (OR 1.20; 95% CI 1.02-1.41; p = 0.03), and low concentrations of vitamin B12 (OR 0.99; 95% CI 0.994-0.999; p = 0.008), whereas for BRVO risk only hypertension was significant (OR 2.74; 95% CI 1.24-6.03; p = 0.01). Genotype distribution of the MTHFR C677T mutation did not reveal any significant difference between patients and controls. These results suggest that elevated fasting HCY levels, low vitamin B12 levels, and hypertension are associated with a risk of RVO, especially for CRVO. Moreover, our data suggest that only hypertension is associated with BRVO risk.

Allelic Frequencies of Mutations in Blood Coagulation Factor Genes(Factor V, Factor II) and Methylenetetrahydrofolate Reductase (MTHFR) in 201 Turkish Patients with Venous Thrombosis Complications

Background and objectives: The objective of this study is to determine the prevalence of factor V Leiden (G1691A), prothrombin (G20210A) and MTHFR (C677T) gene mutations in 201 Turkish patients who were referred to our clinic with venous thrombosis complications such as deep venous thrombosis, ischemic complications, thromboembolism and coronary artery disease. Methods: After isolation of genomic DNA from peripheral blood samples, polymerase chain reaction (PCR) and restriction fragment length polymorphism techniques were used for analysis. Results: Among patients with venous thrombosis complications, allelic frequencies were 0.33, 0.17 and 0.04 for MTHFR (C677T), factor V Leiden (G1691A) and prothrombin (G20210A) mutations respectively. Conclusion: Homozygosity for the MTHFR C677T mutation and/or presence of at least one copy of the A allele of the Factor V Leiden G1691A mutation was found to be associated with increased incidence of venous thrombosis complications in patients (p<0.01). The combined impact of these mutations on venous thrombosis should also be taken into consideration. In our study, prothrombin (G20210A) mutation was found not to be associated with venous thrombosis complications. We also found that the prevalence of factor V Leiden (G1691A), prothrombin (G20210A) and MTHFR (C677T) gene mutations in Turkish patients with venous thrombosis are comparable to results of other studies performed in Turkish and Caucasian populations. We did not observe any significant gender dependency for the factor V Leiden (G1691A), prothrombin (G20210A) and MTHFR (C677T) gene mutations in venous thrombosis complications.

Meta-analysis of MTHFR C677T and A1298C gene polymorphisms: Association with the risk of hepatocellular carcinoma

Several studies have indicated an association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and the risk of hepatocellular carcinoma (HCC). However, the conclusions are inconsistent. Therefore, a meta-analysis was performed. Databases like Pubmed, EMBASE, and EBSCO (up to September 2012) were searched to retrieve case-control trials about MTHFR (C677T or A1298C) polymorphisms and HCC. Literatures were independently screened by two researchers according to the inclusion and exclusion criteria. Data were extracted and analyzed by software STATA 11.0. Nine studies were included with 10 datasets and 5132 cases. C677T polymorphism was associated with HCC risk in a heterozygous model (TT vs. CT: OR=1.20, 95% CI: 1.02-1.40). For the A1298C polymorphism, a significantly decreased HCC risk was found in the dominant, heterozygous and homozygous models (CC vs. AA+AC: OR=0.52, 95% CI: 0.33-0.80; CC vs. AC: OR=0.50, 95% CI: 0.32-0.79; CC vs. AA: OR=0.52, 95% CI: 0.33-0.81). Subgroup analysis stratified by ethnicity and type of control further indicated decreased HCC risks in Asians (CC vs. AA+AC: OR=0.47, 95% CI: 0.26-0.84; CC vs. AC: OR=0.41, 95% CI: 0.24-0.71; CC vs. AA: OR=0.46, 95% CI: 0.27-0.78), studies with controls of healthy people (CC vs. AA: OR=0.54, 95% CI: 0.31-0.93; CC vs. AC: OR=0.54, 95% CI: 0.31-0.94; CC vs. AA+AC: OR=0.55, 95% CI: 0.32-0.94), and controls of non-HCC patients (CC vs. AC: OR=0.43, 95% CI: 0.19-0.96). Homozygous carriers of MTHFR C677T mutation are more susceptible to HCC, but homozygous mutations of MTHFR A1298C may play a protective role for developing HCC.

Association of methylenetetrahydrofolate reductase C677T and A1298C polymorphisms with myocardial infarction in Tunisian young patients

Myocardial infarction (MI) is an important clinical problem because of its large contribution to mortality. The objective of this study is to assess whether two methylenetetrahydrofolate reductase (MTHFR) polymorphisms, C677T and A1298C, were associated with MI among Tunisian patients. One hundred young patients (<47 years old) with MI were recruited and compared with 200 control subjects with no history of MI. The most common MI risk factors were investigated. Fasting plasma homocysteine levels were measured. Genotypes of the MTHFR C677T and A1298 polymorphisms were studied by polymerase chain reaction. The mean plasma homocysteine level in the study group was raised when compared with the control group. Homozygous MTHFR C677T mutation was observed in 2 (2 %) patients and in 17 (8.5 %) control subjects, whereas heterozygous MTHFR C677T mutation was detected in 82 (82 %) patients versus only 79 (39.5 %) in control subjects. The mean total homocysteine concentrations were significantly higher in individuals with the 677TT and CT genotypes. Our results indicate that C677T and A1298C MTHFR mutations and hyperhomocysteinemia contributed to the risk factors for MI.

The Association of MTHFR C677T Gene Variants and Lipid Profiles or Body Mass Index in Patients With Diabetic and Nondiabetic Coronary Heart Disease

The aim of this study is to investigate whether methylenetetrahydrofolate reductase (MTHFR) C677T mutation is associated with the development of hyperlipoproteinemia and obesity in coronary heart disease (CHD). This study was carried out in 82 diabetic and 112 nondiabetic patients with CHD and in 138 CHD-free healthy controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and agarose gel electrophoresis techniques were used to determine the MTHFR C677T. Distributions of MTHFR genotypes (C677T dbSNP: rs1801133) were similar in our study groups (P > 0.05). There was no statistical association between biochemical parameters and genotype distribution in nondiabetic CHD patients, while diabetic CC genotype carriers have elevated levels of body mass index (BMI) independently from lipid profiles (P = 0.002). In diabetic CHD patients, while evaluating the clinical parameters according to gender, it was found that gender had an impact on BMI (P = 0.013). Due to this gender effect, a multivariate analysis was conducted on the diabetic CHD patient group. The multivariate logistic regression analysis confirmed that the MTHFR-CC genotype was associated with elevated BMI levels in diabetic CHD patients (odds ratio [OR] = 5.42, P = 0.003). The results of the present study demonstrated that possessing T allele of MTHFR C677T mutation indicates a protective association on BMI independently from other risk factors.

Methylenetetrahydrofolate reductase C677T mutation in patients with alopecia areata in Turkish population

ObjectiveMethylene-tetrahydrofolate reductase (MTHFR) is a key enzyme regulating folate metabolism and it is thought to influence DNA methylation and nucleic acid synthesis. Mutations in the MTHFR gene have been associated with several autoimmune disorders in previous studies. Alopecia areata (AA) is considered to be a tissue-specific autoimmune disease as the hair follicle has been targeted and antibodies to their own hair follicle structures have been developed. Since there is a common shared pathway between AA and other autoimmune disorders, we aimed to investigate a possible association between the MTHFR gene C677T mutation and AA susceptibility in the Turkish population. MethodsThe study included 136 patients affected by AA and 130 healthy controls. Genomic DNA was isolated and genotyped using a polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) assay for the MTHFR gene C677T mutation. ResultsThe distributions of genotype and allele frequencies of MTHFR gene C677T mutation were statistically different between AA patients and the control group (p=0.036 and p=0.011, respectively). High differences were also observed when the patients and controls were compared according to CC versus CT+TT (p=0.012). CT+TT genotypes and T allele of MTHFR gene C677T mutation were found to be a susceptibility factor for AA in the Turkish population. ConclusionThe results suggest that MTHFR gene C677T mutation may have an effect on the risk of alopecia areata in the Turkish population. This is the first study reporting the association between the MTHFR (C677T) genotype and AA.

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

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.

Prevalence of MTHFR C677T Single Nucleotide Polymorphism in Genetically Isolated Populations in Jordan

Methylenetetrahydrofolate reductase (MTHFR) C677T single nucleotide polymorphism is a major inherited risk factor of venous thromboembolism. We sought to determine its prevalence in genetically isolated populations of Chechens and Circassians in Jordan. The MTHFR C677T mutation was analyzed from blood samples taken from 120 random unrelated Chechens and 72 Circassians. The prevalence of the MTHFR mutation in the Chechen population was 27.5% (allele frequency 15%); the prevalence among the Circassians was 50% (allele frequency 29.2%). The prevalence in the Chechen population is similar to that in Jordan and other world populations, but it is higher in the Circassian population. This study will contribute to understanding the interaction between genetic and environmental risk factors underlying thrombosis and will be useful in deciding which genetic variants should be tested in a clinical genetic testing service.

Association of MTHFR gene C677T mutation with recurrent aphthous stomatitis and number of oral ulcers

Recurrent aphthous stomatitis (RAS) is a common ulcerative disease of the oral mucosa. Methylenetetrahydrofolate reductase (MTHFR) gene variants are associated with thrombophilia and vasculopathy that may result in oral ulceration. Oral ulcers are also the most common feature of Behcet's disease (BD). Association of MTHFR gene C677T mutation with BD has been reported in different populations. The aim of the present study was to investigate the possible association between MTHFR gene C677T mutation and RAS and evaluate if there was an association with clinical features in a relatively large cohort of Turkish patients. The study included 188 patients affected by RAS and 200 healthy controls. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) assay for the MTHFR gene C677T mutation. The genotype and allele frequencies of C677T mutation showed statistically significant differences between RAS patients and controls (p = 0.002 and p = 0.0004, respectively). After stratifying RAS patients according to clinical characteristics of oral ulcers, a significant association was observed between C677T mutation and number of oral ulcers of RAS patients (p = 0.006). As a result, a high association between MTHFR gene C677T mutation and RAS was observed in the present study. Also number of oral ulcers was found to be associated with MTHFR C677T mutation in RAS patients. If our observation can be substantiated with further studies, evaluation for MTHFR mutations and perhaps folate supplementation may become necessary in selected patients.

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.

C677T Methylenetetrahydrofolate Reductase and Plasma Homocysteine Levels among Thai Vegans and Omnivores

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.

Inherited thrombophilia-related complications in the treatment of a biatrial thrombus

The study emphasizes the importance of the high risk of thromboembolism with inherited thrombophilic factors. Transesophageal echocardiography revealed large biatrial masses in an 87-year-old woman with history of nonvalvular atrial fibrillation, pulmonary embolism, and prescribed oral anticoagulation for prophylaxis of embolic events. The surgical removal of the presumed thrombus was declined by the patient and intravenous anticoagulation with unfractionated heparin was initiated. Treatment was complicated by additional embolic events and the patient succumbed after 14 days due to multiple organ failure. Testing revealed heterozygosity for both the factor V Leiden and the methylenetetrahydrofolate reductase C677T mutations inducing resistance to activated protein C. The combination of these thrombophilic factors can probably explain the poor anticoagulant response, embolic events, and the failure of resolution of the biatrial masses.

Thrombophilic Mutations in Iranian Patients With Thrombophilia

Objectives To investigate the frequency and type of Factor V Leiden (FVL), prothrombin, and methylenetetrahydrofolate reductase (MTHFR) mutations in ethnic Iranian patients and to evaluate the correlation between platelet count and thrombotic mutations. Methods This descriptive epidemiologic case study was performed with 208 patients with thrombotic disorders and hemorrhaging who were referred to Payvand Medical and Specialty Laboratory in Tehran, Iran, from 2007 through 2010. Peripheral blood samples from patients with abnormal thrombosis were analyzed for FVL, prothrombin G20210A, and MTHFR (A1298C and C677T) mutations, respectively. Mutation analysis was accomplished by polymerase chain reaction (PCR)–reverse dot blot. Platelet counts were obtained by automated cell count. Results Thrombophilic mutations were observed in 105 cases of 208 patients, including 13 patients with FVL, 51 patients with MTHFR C677T mutation, 33 patients with MTHFR A1298C mutation, and 8 patients with prothrombin G20210A mutation. Eighteen patients showed 2 simultaneous mutations and 3 patients showed 3 simultaneous mutations. According to our results, platelet counts were in normal range, so no statistically significant difference was observed between platelet count and mutation type. Conclusions The frequency of MTHFR C677T mutation is higher than that of FVL and/or prothrombin 20210A mutations in ethnic Iranian patients with thrombophilia. Also, thrombophilic mutations were not observed to have any effect on platelet count in patients with thrombophilia. Regarding the high prevalence of MTHFR C677T mutation in our region, family members of any patient with the MTHFR C677T mutation should be screened to identify this genetic mutation. * Abbreviations : FVL : Factor V Leiden APC : activated protein C MTHFR : methylene-tetrahydrofolate reductase EDTA : ethylenediaminetetraacetic acid PCR : polymerase chain reaction SSOP : sequence-specific oligonucleotide probes BCIP : 5-bromo-4-chloro-3-indolyl phosphate NBT : nitro blue tetrazolium PT : partial thrombosis PLT : platelet RFLP : restriction fragment length polymorphism BP : base pair

Evaluation of C677T Polymorphism of the Methylenetetrahydrofolate Reductase (MTHFR) Gene in various Neurological Disorders

Abstract Background: Genetic risk factors play an important role in neurological disorders. In this case-control study, we examined the C677T polymorphism (rs1801133) in the Methylenetetrahydrofolate reductase (MTHFR) gene and its association with three neurodegenerative disorders: The late onset pathology, Alzheimer disease and two early onset ones, Autism and Down syndrome. New evidence suggests that autism may be associated with varied behavioural responses to folate therapy and metabolic anomalies, including those in folate metabolism, that contribute to hypomethylation of DNA. We hypothesis that, MTHFR C677T mutation may be the underlying common risk factor in various neurological disorders leading to impaired one carbon metabolism resulting in similar and severe neuropsychological symptoms. Hence our objective was to evaluate MTHFR C677T polymorphism in different Neurological disorders and compare it with age-matched healthy controls. Method: This case-control study was carried out on 200 samples which included 100 patients with different neurological disorders and 100 healthy individuals without any neurological problems taken as the control group. MTHFR polymorphism was assessed by PCR-RFLP. Results: Results indicated that the C677T MTHFR polymorphism was not significantly different between controls of younger and older age groups. Among the three neurological disorders studied the T allele was associated with autism (TT+CT vs. CC; OR=4.472, 95% CI: 1.605-12.799, p<0.002), but not with the other two conditions. Conclusion: In conclusion, despite the smaller sample size, the C677T polymorphism of MTHFR plays a role in some complex neurodevelopmental disorders and not in others.

MTHFR gene C677T mutation and ACE gene I/D polymorphism in Turkish patients with osteoarthritis.

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.