Methylenetetrahydrofolate Reductase Genotype Research Articles

Effect of plateletcrit and methylenetetrahydrofolate reductase (MTHFR) C677T genotypes on folic acid efficacy in stroke prevention

Previous studies have shown that low platelet count combined with high plasma total homocysteine (tHcy) increased stroke risk and can be lowered by 73% with folic acid. However, the combined role of other platelet activation parameters and the methylenetetrahydrofolate reductase (MTHFR) C677T genotypes on stroke risk and folic acid treatment benefit remain to be examined. This study aimed to investigate if platelet activation parameters and MTHFR genotypes jointly impact folic acid treatment efficacy in first stroke prevention. Data were derived from the China Stroke Primary Prevention Trial. This study includes a total of 11,185 adult hypertensive patients with relevant platelet activation parameters and MTHFR genotype data. When simultaneously considering both platelet activation parameters (plateletcrit, platelet count, mean platelet volume, platelet distribution width) and MTHFR genotypes, patients with both low plateletcrit (Q1) and the TT genotype had the highest stroke incidence rate (5.6%) in the enalapril group. This subgroup significantly benefited from folic acid treatment, with a 66% reduction in first stroke (HR: 0.34; 95% CI: 0.14–0.82; p = 0.016). Consistently, the subgroup with low plateletcrit (Q1) and the CC/CT genotype also benefited from folic acid treatment (HR: 0.40; 95% CI: 0.23–0.70; p = 0.001). In Chinese hypertensive adults, low plateletcrit can identify those who may greatly benefit from folic acid treatment, in particular, those with the TT genotype, a subpopulation known to have the highest stroke risk.

Assessing the possible association between MTHFR (rs1801133) and GPx-1 (rs1050450) polymorphisms with the risk of type 2 diabetes, diabetic neuropathy, and diabetic retinopathy.

Oxidative stress in chronic hyperglycemia could injure the tissues and onset of diabetes-related complications like retinopathy and neuropathy. This study investigates the association between methylenetetrahydrofolate reductase (MTHFR) and glutathione peroxidase (GPx) genetic variants with these complications. In this case-control study, 400 individuals, including 100 healthy subjects and 300 patients with type 2 diabetes mellitus (T2DM) in three subgroups: with retinopathy(n = 100), with neuropathy(n = 100), and without complication (n = 100) from West Iran, were studied. MTHFR (rs1801133) and GPx-1 (rs1050450) variants were identified by the PCR-RFLP method. The plasma levels of GPx activity, glutathione, malondialdehyde (MDA), total antioxidant capacity (TAC), and total oxidative stress (TOS) were measured by chemical methods. Higher BMI, TOS and MDA levels were observed in patients with neuropathy compared to other patients and controls. Diabetic patients with neuropathy had lower levels of glutathione (7.8 ± 4.5; P < 0.001), GPx activity (39.5 ± 8.5; P < 0.001), and TAC (703.1 ± 129.1; P = 0.0001) in comparison with other groups. The patients without complication and retinopathic patients had higher plasma levels of glutathione (12.2 ± 2.4; p = 0.02) and TAC (793.4 ± 124.6; P < 0.001), respectively. MTHFR TT genotype significantly correlated with lower levels of TOS (3.5 ± 1.1; P < 0.001) and OSI (0.0050 ± 0.001; P < 0.001). Subjects with the GPx-1 TT genotype had higher levels of MDA (6.8 ± 2.5; P = 0.02) and lower levels of TOS (3.7 ± 1.6; P < 0.001), which is statistically significant. TT genotype of MTHFR was associated with 3.9 fold (95% CI 1.04-4.76; P = 0.0436) increased risk of neuropathy. Also, GPx-1 CT genotype increased the risk of retinopathy [OR = 2.7 (95% CI = 1.38-5.44; P = 0.0039)]. The MTHFR TT genotype increased the risk of neuropathy in diabetic patients significantly. The GPx-1 CT genotype is related to increased retinopathy risk among diabetic patients. Both MTHFR and Gpx-1 TT genotypes were associated with higher BMI levels.

Homozygous MTHFR C677T carriers develop idiopathic portal vein thrombosis 20 years earlier than wild type.

The aim of this study was to evaluate the impact of methylene tetrahydrofolate reductase (MTHFR) rs1801133 (C→T667 transition) on age at first idiopathic portal vein thrombosis (PVT) and to identify clinical and/or laboratory variables influencing age at first PVT, including plasma homocysteine and the prothrombin rs1799963 PT (G→A transition at position 20210) (PT) mutation. A retrospective cross-sectional cohort, including 15 MTHFR TT, 32 MTHFR TC and 22 MTHFR CC idiopathic PVT participants contributing demographics, age at PVT, plasma concentrations of homocysteine and of natural anticoagulants. MTHFR TT carriers presented with a lower age at PVT than heterozygous or wild-type genotypes (31 ± 8 vs. 48 ± 15 vs. 52 ± 13 years, P = 0.001) and were more likely to have a plasma HC concentration above the cut-off (73.3 vs. 32 vs. 50%, P = 0.04). MTHFR TT and protein C predicted age at PVT (P < 0.0001 and P = 0.06); MTHFR TT predicted plasma homocysteine (P = 0.05). In the MTHFR TT group, plasma homocysteine inversely related to protein C (P = 0.03). Plasma homocysteine predicted the extent of PVT (P = 0.03). Compound MTHFR TT + PT GA did not lower age at first PVT compared to MTHFR TT alone (35 ± 9 vs. 30 ± 8 years). MTHFR TT is associated with a 20-year earlier PVT presentation than heterozygous and wild-type MTHFR genotypes. The inverse relation between plasma homocysteine and protein C contributes to the prematurity of PVT in the MTHFR TT group, whereas plasma homocysteine contributes to the extent of PVT. The recent exclusion of MTHFR genotyping from the thrombophilia screen needs revisiting in this setting.

Association of liver fibrosis with extrahepatic cancer in steatotic liver disease patients with PNPLA3 I148M GG genotype.

The impacts of patatin-like phospholipase domain-containing protein 3 (PNPLA3) I148M-rs738409, methylenetetrahydrofolate reductase (MTHFR) Ala222Val-rs1801133, and aldehyde dehydrogenase 2 (ALDH2) Glu504Lys-rs671 on the outcomes of Taiwanese patients with steatotic liver disease (SLD) have remained elusive. An 8-year prospective cohort study of patients with (n = 546) and without (n = 580) SLD (controls) was undertaken in a Taiwanese tertiary care center. The 546 SLD patients comprised 306 (56.0%) men and 240 (44.0%) women with mean ages of 53.3 and 56.4 years, respectively. Compared with the controls, SLD patients had an increased frequency of the PNPLA3 I148M-rs738409 GG genotype (25.5 vs. 5.9%, p = 0.001). Among the SLD patients, 236 (43.1%) suffered cardiovascular events, 52 (9.5%) showed extrahepatic cancers, 13 (2.38%) experienced hepatic events, including hepatocellular carcinoma (n = 3, 0.5%) and liver cirrhosis (n = 8, 1.47%), and none died. The Fibrosis-4 (FIB-4) scores were associated with extrahepatic cancer (hazard ratio [HR] 1.325; 95% confidence interval [CI], 1.038-1.691) and cirrhosis development (HR 1.532; 95% CI, 1.055-2.224), and the PNPLA3 I148M-rs738409 G allele (β = 0.158, 95% CI, 0.054-0.325) was associated with the FIB-4 score. Stratified analyses showed that the impact of the FIB-4 score on extrahepatic cancer development was evident only in SLD patients with the PNPLA3 I148M-rs738409 GG genotype (HR 1.543; 95% CI, 1.195-1.993) and not in patients with the GC or CC genotype. Moreover, the ALDH2 Glu504Lys-rs671 G allele had a dose-dependent effect on alcoholism, and the MTHFR and ALDH2 genotypes were not significantly associated with SLD patient outcomes. In conclusion, special vigilance should be exercised for emerging extrahepatic cancer in SLD patients with the PNPLA3 I148M-rs738409 GG genotype and high FIB-4 scores.

Relationship between MTHFR gene polymorphism and risk of thrombosis in postoperative patients with colorectal cancer.

An association between the methylenetetrahydrofolate reductase (MTHFR) C667T genotype and the risk of colorectal cancer, as well as a link between MTHFR gene polymorphism and thrombosis, have been revealed. However, the connection between MTHFR gene polymorphism and the risk of thrombosis in patients with colorectal cancer has remained to be fully elucidated. The present study investigated the link between MTHFR gene polymorphism and basic clinical data, postoperative D-dimer (DDi), postoperative thromboelastogram and postoperative thrombosis in 591 patients who underwent surgery for colorectal cancer. Postoperative DDi, thromboelastogram and postoperative thrombosis were not significantly different among patients with colorectal cancer and different MTHFR genotypes. While the results were 'negative', the present study may help physicians understand that it is not necessary to detect MTHFR polymorphism for therapeutic purposes. Regarding the danger of venous thrombosis, more focus should be placed on the standardized procedural enforcement system for deep vein thrombosis prevention for patients undergoing pelvic and abdominal surgery.

MTHFR C677T and A1298C polymorphism’s effect on risk of colorectal cancer in Lynch syndrome

Lynch syndrome (LS) is characterised by an increased risk of developing colorectal cancer (CRC) and other extracolonic epithelial cancers. It is caused by pathogenic germline variants in DNA mismatch repair (MMR) genes or the EPCAM gene, leading to a less functional DNA MMR system. Individuals diagnosed with LS (LS individuals) have a 10–80% lifetime risk of developing cancer. However, there is considerable variability in the age of cancer onset, which cannot be attributed to the specific MMR gene or variant alone. It is speculated that multiple genetic and environmental factors contribute to this variability, including two single nucleotide polymorphisms (SNPs) in the methylenetetrahydrofolate reductase (MTHFR) gene: C677T (rs1801133) and A1298C (rs1801131). By decreasing MTHFR activity, these SNPs theoretically reduce the silencing of DNA repair genes and increase the availability of nucleotides for DNA synthesis and repair, thereby protecting against early-onset cancer in LS. We investigated the effect of these SNPs on LS disease expression in 2,723 LS individuals from Australia, Poland, Germany, Norway and Spain. The association between age at cancer onset and SNP genotype (risk of cancer) was estimated using Cox regression adjusted for gender, country and affected MMR gene. For A1298C (rs1801131), both the AC and CC genotypes were significantly associated with a reduced risk of developing CRC compared to the AA genotype, but no association was seen for C677T (rs1801133). However, an aggregated effect of protective alleles was seen when combining the alleles from the two SNPs, especially for LS individuals carrying 1 and 2 alleles. For individuals with germline pathogenic variants in MLH1, the CC genotype of A1298C was estimated to reduce the risk of CRC significantly by 39% (HR = 0.61, 95% CI 0.42, 0.89, p = 0.011), while for individuals with pathogenic germline MSH2 variants, the AC genotype (compared to AA) was estimated to reduce the risk of CRC by 26% (HR = 0.66, 95% CI 0.53, 0.83, p = 0.01). In comparison, no association was observed for C677T (rs1801133). In conclusion, our study suggests that combining the MMR gene information with the MTHFR genotype, including the aggregated effect of protective alleles, could be useful in developing an algorithm that estimates the risk of CRC in LS individuals.

Analysis of the risk factors in patients with unexplained recurrent spontaneous abortion.

We aimed to explore the risk factors in patients with unexplained recurrent spontaneous abortion (URSA) and to provide a basis for clinically targeted therapy. This case-control study comprised 202 patients with URSA treated at our hospital and 115 women in early pregnancy with a normal birth history during the same period. After procuring the data we conducted a multivariate logistic regression analysis of risk factors related to URSA. Logistic regression analysis showed (i) that the number of spontaneous abortions (SAs; odds ratio [OR]=492.123), the levels of autoantibodies (OR=19.322) and tumor necrosis factor alpha (TNF-α; OR=9.615), and the CT and TT genotypes of methylenetetrahydrofolate reductase (MTHFR) C677T (OR=6.217 and 15.009, respectively) were risk factors for URSA and (ii) that 25-hydroxyvitamin D (25-(OH)D; OR=0.919) was a protective factor. The most important risk factor was a history of one or more SAs, with the risk of pregnancy loss increasing 491.123-fold. Every unit increase in serum 25-(OH)D reduced the risk of SA by 8.1%. The risk factors for URSA included the number of SAs, the levels of autoantibodies and TNF-α, and the MTHFR C677T T allele; 25-(OH)D was a protective factor. We recommend that women diagnosed with URSA receive intervention as soon as possible so as to actively reduce the incidence of recurrent SA.

Correlation analysis of age and MTHFR C677T polymorphism with sperm motility and sperm DNA integrity.

Several factors, including age and polymorphisms in genes such as MTHFR, affect sperm quality. However, the relationship between MTHFR C677T polymorphism and infertility remains unclear. Hence, the purpose of this study was to investigate the effects of age and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on the forward progressive sperm motility and sperm DNA integrity. For this purpose, a total of 845 men were recruited from the hospital's infertility clinic for semen analysis, sperm DNA integrity testing, and MTHFR C677T genotyping. The participants were grouped by age (<30 years, 30-35 years, >35 years) to determine the relationship between age and the progressive motility of sperms (PR%) and sperm DNA integrity. The effect of MTHFR C677T polymorphism on sperm motility and sperm DNA integrity was also analyzed in all the age groups. Results showed that PR% and DNA fragmentation index (DFI) differed significantly among the groups (P<0.001). The correlation analysis showed that age was positively correlated with DFI and negatively correlated with PR%. DFI correlated negatively with PR% (P <0.01). When the age groups were classified based on the C677T genotype, we observed that PR% and DFI did not differ significantly between different genotypes within the same age range (P>0.05). The conclusion was that age exerted a negative effect on sperm motility and sperm DNA integrity. Age correlated positively with DFI and negatively with PR%. MTHFR C677T polymorphism did not affect forward motile sperm count and sperm DNA integrity. Our observations will be useful for fertility guidance and MTHFR genotype interpretation in the clinic for couples of childbearing age.

Associations of serum 25-hydroxyvitamin D with serum folate, cobalanin, and homocysteine concentrations and methylene tetrahydrofolate reductase (MTHFR) gene polymorphisms in healthy adults.

The aim of this study was to investigate the associations of serum 25-hydroxyvitamin D [25(OH)D] with various demographic, anthropometric, and genetic characteristics and biochemical parameters in healthy Greek adults. Demographic (age and sex), anthropometric (body mass index/BMI), and genetic (MTHFR gene polymorphisms) characteristics and biochemical parameters (serum folate, cobalamin/Cbl, and total homocysteine/tHcy concentrations), which had been recorded and measured, among others, in the framework of periodic medical examination (military personnel) or check-up (non-military personnel) of 383 healthy Greek adults (199 men and 184 women) were analyzed. Serum 25(OH)D, tHcy, folate, and Cbl levels were determined using immunoassay methods. The MTHFR C677T and A1298C gene polymorphisms were genotyped using polymerase chain reaction and reverse hybridization. Serum 25(OH)D concentrations were correlated with Cbl levels and MTHFR C677T gene polymorphism, while they had a reverse correlation with serum tHcy levels, age, and BMI. There was no significant correlation between serum 25(OH)D concentrations and sex, serum folate levels, and smoking status. Individuals with the 677TT genotype had statistically significantly lower serum 25(OH)D levels than those with the 677CC or 677CT genotype, while individuals with the 1298CC genotype had statistically significantly higher serum 25(OH)D levels than those with 1298AA or 1298AC genotype. Moreover, the reverse correlation between the serum 25(OH)D and tHcy levels was statistically significant in all six MTHFR genotypes. Serum 25(OH)D levels are associated with age, BMI, serum tHcy, and Cbl levels and MTHFR C677T gene polymorphism. The most significant finding of our study is the observed reverse correlation of serum 25(OH)D levels with serum tHcy levels. Considering that vitamin D deficiency and hyperhomocysteinemia (HHcy) are associated with an increased risk for cardiovascular diseases (CVDs), we suggest that individuals with high serum tHcy levels should be further investigated for, inter alia, their serum 25(OH)D levels.

MTHFR polymorphisms and neurotoxicity and overall survival after methotrexate-based therapy in primary CNS lymphoma.

2079 Background: The folate-antagonist methotrexate (HD-MTX) is an integral to induction chemotherapy for primary CNS lymphoma (PCNSL); however, it can be associated with toxicities, including injury to cerebral white matter known as leukoencephalopathy. Methylenetetrahydrofolate Reductase (MTHFR) is involved in intracellular folate metabolism, and MTHFR polymorphisms may affect CNS-specific side effects of HD-MTX. Here, we evaluated the possible association of MTHFR polymorphisms an HD-MTX related CNS toxicity. Methods: We retrospectively searched our institutional database at the Massachusetts General Hospital for newly diagnosed PCNSL patients treated with HD-MTX (without use of radiotherapy or intrathecal chemotherapy). MTHFR polymorphisms were correlated with evolution of leukoencephalopathy over a time period of five years and patient outcomes. ROC curves were generated to estimate the diagnostic ability of specific MTHFR genotypes. Survival was calculated using Kaplan-Meier survival analysis and log-rank test. The significance level was set at p ≤ 0.05. Results: Among 68 PCNSL patients, MTHFR polymorphisms were found in 60 individuals (88.2%; 677C&gt;T: 29 patients, 1298A&gt;C: 18 patients, combined 677C&gt;T &amp; 1298A&gt;C: 13 patients). Neither MTX clearance nor disease response to HD-MTX was affected by specific genotypes, and complete response was achieved in 72.1% of patients by induction with HD-MTX-based therapy. However, the 1298A&gt;C genotype was associated with increased frequency and severity of leukoencephalopathy over time (χ2 = 7.43). Such genotype predicted treatment-induced leukoencephalopathy with a sensitivity of 71.0%% and a specificity of 62.2% (ROC: p = 0.019). While progression-free survival did not differ in genotype-based subgroups, overall survival was significantly lower when the 1298A&gt;C genotype was present. Conclusions: The MTHFR 1298A&gt;C genotype may serve to identify PCNSL patients at elevated risk for HD-MTX-induced leukoencephalopathy. This was associated with reduced overall survival, potentially due to decreased functional status in patients less suitable for aggressive subsequent therapies.

Maternal pre-pregnancy BMI, MTHFR polymorphisms, and the risk of adverse pregnancy outcomes in pregnant women from South China: a retrospective cohort study

BackgroundIncreasing evidence suggests an association between maternal pre-pregnancy body mass index (pre-BMI) and adverse pregnancy outcomes. However, the effects of methylenetetrahydrofolate reductase (MTHFR) polymorphisms on these relationships require further investigation. This study aimed to investigate whether the relationship between pre-BMI and the risk of adverse pregnancy outcomes was influenced by MTHFR gene polymorphisms.MethodsA total of 5614 mother-fetus pairs were included in the study. The odds ratios (OR) of adverse pregnancy complications, including gestational diabetes mellitus (GDM), gestational hypertension (GHT), cesarean delivery (CS), and premature rupture of membranes (PROM), were estimated using adjusted logistic regression models and subgroup analysis.ResultsPregnant women with higher pre-BMI values were positively related to the risk of GDM, GHT, and CS. In the subgroup analysis, underweight BMI was associated with a decreased risk of CS and GDM in pregnant women with the MTHFR A1298C AA or C677T CC genotype, while overweight/obese BMI was associated with an increased risk of GDM and CS in different MTHFR variants. Moreover, pregnant women with MTHFR A1298C AC + CC or C667T CC were found to have an increased risk of GHT in the MTHFR A1298C AA or C667T CT + TT genotype. A remarkable association was observed between the obesity group with MTHFR A1298C AC + CC (OR = 6.49, CI: 2.67–15.79) and the overweight group with the C667T CC genotype (OR = 4.72, CI: 2.13–10.45).ConclusionsMTHFR gene polymorphisms exert a modifying effect on the association between maternal pre-BMI and the risk of GHT, CS, and GDM. Pregnant women with a high pre-BMI with specific MTHFR genotypes should be considered for GHT development.

5566409 IMPACT OF GENETIC VARIATIONS ON THROMBOTIC RISK OF SICKLE CELL DISEASE IN SAUDI PATIENTS

Introduction: Sickle cell disease (SCD) patients are at higher risk of developing venous thromboembolism (VTE) in comparison to healthy individuals (1). The prevalence of VTE in SCD patients is 8.4-11.3% in the Saudi population (2-3), whereas rates are extremely lower in healthy people (0.1 %). This might be attributed to several risk factors, in particular genetic predisposition. Certain mutations, rs6025 (G1691A) in Factor V Leiden (FVL), rs1799963 (G20210A) in Prothrombin (PRT, FII), and rs1801133 (C677T) in Methylenetetrahydrofolate Reductase (MTHFR) are associated with hypercoagulability status involved in various thrombophilic conditions (4). Thus, we aimed to assess the impact of genetic mutations on VTE development in SCD patients. Method: 350 SCD Saudi adult patients (65 cases with a history of VTE and 285 SCD controls without VTE) were genotyped using 10x Affymetrix Axiom Array which includes 812,820 markers for Genome-Wide Association Study (GWAS). PLINK software version 1.07 was used to analyse GWAS data. Genotyping statistical differences between cases and controls were assessed using Fisher’s exact test. Calculations of means and standard deviations were performed to assess matching of the age factor using SPSS 27.0 program and the differences were measured using the 2-independent samples t-test. Institutional Review Board (IRB) approval (ref RC19-083-R) was obtained from King Abdullah International Medical Research Centre, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard – Health Affairs, Riyadh, Saudi Arabia. Results: Matching was confirmed for age and sex between cases and controls. No significant differences seen in genotypes of FVL (rs6025), PRT (rs1799963), and MTHFR (rs1801133) between the cases and control groups (P=0.34, 1.0, and 0.87, respectively). GWAS analysis has identified 6 association signals at threshold of P<5×10-8, rs139341092 is an indel variant located at chromosome (chr) 20, rs76076035 an intron variant at chr 9, and four variants (three intronic (rs35390334 and rs331532 in strong linkage disequilibrium (LD), and rs372091) and one exonic (rs317777 in OLFM5P) at chr 11. Eight polymorphisms with a significance P-value <5×10-7 were detected; two of them are functional variants (rs73395847, a splice acceptor variant in C11orf40 gene at chr 11 and rs6554634, a transcription factor binding site variant at chr 5). Moreover, 53 variants with an association significance (P-value) <5×10-6 were discovered, 14 of them have known clinical significance. Two of them are missense variants (rs7933549 in OR51V1 at chr 11 and rs111681839 in CEP131 at chr 17), whereas the remaining variants (n=12) are regulatory variants; five of them (rs2071348, rs73402629, and rs73402631 are in LD, in addition to rs2213170 and rs2213169) located at chr 11 and the other seven located at chr 6 (rs145017319), chr 8 (rs16904858 and rs77365846), chr 9 (rs2289658 in NTRK2), chr 16 (rs142329036), chr 20 (rs139719409), and chr 21 (rs73189215). Two of the detected intron variants located at chr 11 (rs1455957 and rs11035718) were found to be in strong LD with a missense variant (rs2472530) in OR52A5 gene at chr 11 too. Conclusion: This study showed no impact of FVL, PRT, and MTHFR on VTE induced in Saudi patients with SCD. However, significant GWAS novel associations, at levels of P<5×10-8 to P<5×10-6, between VTE in SCD with 67 variants were identified which need further replication studies to be confirmed.

MTHFR Polymorphisms and Cardiac Parameters in Patients with Diabetic Retinopathy.

Diabetes Mellitus (DM) is directly associated with cardiovascular dysfunctions and microvascular complications, such as diabetic retinopathy (DR). The association between DR and increased risks of developing cardiovascular diseases has been described. The low activity of the Methylenetetrahydrofolate reductase (MTHFR), an enzyme involved in the metabolism of homocysteine, can lead to hyperhomocysteinemia that has already been related to cardiac outcomes and resistance to insulin. The A1298C and C677T polymorphisms in the MTHFR can reduce enzyme activity. The study aims to analyze the association between MTHFR genotypes and cardiac parameters in patients with DR. DM patients diagnosed with DR (n=65) were categorized and compared according to MTHFR genotypes A1298C (AA and AC+CC groups) and C677T (CC and CT+TT) groups; biochemical, cardiological, anthropometric, genetic, lifestyle and vitamin B9 and B12 consumption variables. Fischer's exact test and Poisson regression were performed to assess the relationship between variables. Comparing echocardiographic and electrocardiogram parameters within genotypic groups, we found a significant association between left atrial dilation and C677T polymorphism. Left atrium diameter was higher in the T allele carriers (CT+TT group), with a prevalence ratio of 0.912. This association was confirmed in the regression model, including confounding variables. The other cardiac structural and functional parameters studied were not significantly associated with the A1298C or C677T genotypes. The MTHFR C677T genotype may contribute to atrial remodeling in RD patients. We found an association between the diameter of the left atrium and the T allele of the MTHFR C677T polymorphism in patients with DR.

Infant blood concentrations of folate markers and catabolites are modified by 5,10-methylenetetrahydrofolate reductase C677T genotype and dietary folate source

BackgroundFolate intake and polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene may affect folate metabolism in infants. ObjectivesWe investigated the association between infant’s MTHFR C677T genotype, the dietary folate source, and concentrations of folate markers in the blood. MethodsWe studied 110 breastfed infants (reference) and 182 infants who were randomly assigned to receive infant formulas enriched with either 78 μg folic acid or 81 μg (6S)-5-methyltetrahydrofolate (5-MTHF) per 100 g milk powder for 12 wk. The blood samples were available at the ages of <1 mo (baseline) and 16 wk. MTHFR genotype and concentrations of folate markers and catabolites [i.e., para-aminobenzoylglutamate (pABG)] were analyzed. ResultsAt baseline, carriers of the TT genotype (vs. CC) had lower mean (SD) concentrations (all in nmol/L) of red blood cell (RBC) folate [1194 (507) vs. 1440 (521), P = 0.033) and plasma pABG [5.7 (4.9) vs. 12.5 (8.1), P < 0.001] but higher plasma 5-MTHF [33.9 (16.8) vs. 24.0 (12.6), P < 0.001]. Irrespective of the genotype, infant formula with 5-MTHF (vs. folic acid) caused a significant increase in RBC folate concentration [1278 (466) vs. 947 (552), P < 0.001]. In breastfed infants, plasma concentrations of 5-MTHF and pABG increased significantly by 7.7 (20.5) and 6.4 (10.5), respectively, from baseline to 16 wk. Infant formula that complies with the present EU legislation for folate intake increased RBC folate and plasma pABG concentrations at 16 wk (P < 0.001) than formula-fed infants. At 16 wk, plasma pABG concentrations remained ∼50% lower in carriers of the TT (vs. the CC) genotype among all feeding groups. ConclusionsFolate intake from infant formula according to the present EU legislation increased RBC folate and plasma pABG concentrations in infants to a greater extent than breastfeeding, particularly in carriers of the TT genotype. However, this intake did not completely abolish the between-genotype differences in pABG. Whether these differences have any clinical relevance, however, remains unclear. This trial was registered at clinicaltrials.gov as NCT02437721.

A Potential Strategy for Atherosclerosis Prevention in Modernizing China - Hyperhomocysteinemia, MTHFR C677T Polymorphism and Air Pollution (PM2.5) on Atherogenesis in Chinese Adults.

Atherosclerosis is one of the most important global health hazards and air pollution (AP, PM2.5) has been implicated. In addition to traditional risk factors hyperhomocysteinemia (HC) has been recognized in many parts of China related to risk of stroke. To evaluate the impact of HC (homocysteine >14μmol/l) and PM2.5 air pollution on atherogenesis in modernizing China, we studied 756 asymptomatic Chinese in China from 1998-2007. PM2.5 exposure, HC, folate, and methylenetetrahydrofolate reductase (MTHFR) C/T genotype were evaluated. Brachial flow-mediated dilation (FMD) and carotid intima-media thickness (IMT) were measured by ultrasound. Locations were categorized as zones 1, 2 and 3, with increasing PM2.5 exposure. HC was higher (19.4±13.1 and 27.1±25.1μmol/l) in high PM2.5-polluted zones 2 and 3 than in zone 1 (9.7±4.5μmol/l, p<0.0015). The top HC tertile was characterized by lower folate and vitamin B12, but a higher proportion of the MTHFR TT genotype, Metabolic Syndrome (MS) and PM2.5 level (p=0.0018). FMD was significantly lower (7.3±2.3%) and carotid IMT thicker (0.63±0.12mm) in the top HC tertile, compared with low HC tertile (8.4±2.5%, p<0.0001; 0.57±0.1mm, p<0.0001 respectively). Similar differences in FMD and IMT were seen in zones 2 and 3, compared with zone 1 (p<0.0001). On multivariate regression, HC was related to male gender (beta=0.106, p=0.021), MTHFR-TT (beta=0.935, p<0.0001), locations (beta=0.230, p<0.0001) and folate-MTHFR interaction (beta=-0.566, p<0.0001). FMD was related to age (beta= -0.221; p<0.0001), male gender (beta= -0.194, p=0.001) PM2.5 and location (beta=-0.285 to -0.303, p<0.0001). Carotid IMT was related to PM2.5 (beta=0.173, p<0.0001), HC (0.122, p=0.006) but not to MTHFR or location, independent of age, gender, MS, and LDL-C. No significant HC-PM2.5 interaction effect on FMD and IMT was observed. HC and PM2.5 pollution but not MTHFR genotype were both related to carotid IMT, independent of other traditional risk factors. This has potential implications in dietary and AP strategies for atherosclerosis prevention in China.

[Assessment of the role of nutritional and genetic determinants in the formation of the risk of diseases associated with folate cycle disorders in the population of the Omsk region].

A number of essential nutrients are involved in the folate cycle, and its effectiveness depends on the sufficient intake of them. In addition, polymorphic variants of the methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR) and methionine synthase (MTR) genes affect a wide range of biochemical reactions of the folate cycle and should also be considered as a risk factor for the development of a number of diseases. The purpose of this research was to study the prevalence of these risk factors. Material and methods. The prevalence of polymorphisms of the folate cycle genes: C677T polymorphism of the MTHFR gene and A66G polymorphism of the MTRR gene in a random stratified (by sex and age) sample of the adult population of the Omsk region [n=139, 51 men, 88 women, aged 18 to 75 years, median age 37 (26; 48) years] was studied. The identification of polymorphisms was carried out by the method of allele-specific polymerase chain reaction with an electrophoretic detection scheme. Using the food intake frequency questionnaire, the dietary intake of nutrients involved in the folate cycle was determined: B vitamins (B6, B2, B9, B12), methionine, choline, in a representative stratified sample of residents of the Omsk region [n=421, 177 men, 244 women, aged 18 to 83 years, median age 37 (23; 57) years]. Results. MTHFR genotypes (A222V С677T C>T) were distributed as follows: CC-type - 51.3%, CT - 41.0%, TT - 7.7%; MTRR genotypes (I22M A>G): AA type - 57.9%, AG - 30.3%, GG - 11.8%. The analysis of actual nutrition showed consumption below the recommended dietary intake of folates in 88.2% persons, vitamin B2 and choline - in 40.5%, vitamin B6 - in 29.2%, methionine - in 22.0%. Vitamin B12 intake was within the recommended range. Conclusion. The totality of the data presented indicates the combined influence and wide distribution of factors that determine the low efficiency of the folate cycle, and, as a result, a high risk of developing a characteristic pathology for the adult population of the region, which determines the need and priorities for prevention measures, including healthy nutrition.

The association between MTHFR polymorphism, dietary methyl donors, and childhood asthma and atopy.

Studies investigating the genetic association of the C677T methylenetetrahydrofolate reductase (MTHFR) genotype and dietary methyl donors with asthma and atopy are limited, and have variable results. To investigate the effect of dietary methyl donor intake on the risk of childhood asthma and atopy, based on the C677T polymorphism in the MTHFR gene. This cross-sectional study included 2,333 elementary school children aged 6-8 years across Korea during 2005 and 2006, as part of the first Children's Health and Environmental Research survey. Genotyping for the MTHFR (rs1801133) polymorphism was performed using the TaqMan assay. Multivariable-adjusted logistic regression analysis was performed to determine a descriptive association between the dietary methyl donor intake, MTHFR polymorphism, and childhood asthma and atopy. Intake of dietary methyl donors like folates was significantly associated with a decreased risk of the wheezing symptom, in the past 12 months, and "ever asthma" diagnosis, respectively. Vitamin B6 intake was also associated with a decreased atopy risk. The T allele of the MTHFR (rs1801133) gene was significantly associated with a decreased risk of atopy. Increased intakes of folate, vitamin B2, and vitamin B6 were protective factors against atopy, especially in children with the T allele on the MTHFR gene, compared to those with lower intakes and the CC genotype. High intakes of dietary methyl donors were associated with reduced risk of atopy and asthma symptoms. These may have additive effects related to the susceptibility alleles of the MTHFR gene. The clinical implications require evaluation.

Relationship between methylenetetrahydrofolate reductase gene polymorphisms and methotrexate drug metabolism and toxicity.

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children, and methotrexate (MTX) is the key drug for ALL. Studies on the relationship between High-Dose methotrexate (HD-MTX) toxicity and methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C genes have drawn different conclusions. This study aimed to investigate the relationship between the polymorphism of MTHFR C677T and A1298C genes and the toxicity responses of MTX. The MTHFR C677T and A1298C genotypes of 271 children with ALL who received HD-MTX chemotherapy in southern China from September 2017 to June 2021 were analyzed, and the toxicity of HD-MTX was evaluated and analyzed according to Common Terminology Criteria for Adverse Events (CTCAE) 5.0. The MTHFR C677T and A1298C gene polymorphisms were not correlated with the 48-hour MTX blood concentrations (P>0.05). Unconditional logistic regression model analysis also revealed that the risk of liver function impairment [odds ratio (OR) =1.656, 95% confidence interval (CI): 1.179-2.324, P<0.05] and mucosal damage (OR =1.508, 95% CI: 1.042-2.183, P<0.05) were 1.656 and 1.508 times higher for the heterozygous mutant (CT), and homozygous mutant (TT) mutant type than for the wild-type (CC), wild-type, respectively. The risk of neutropenia and liver function impairment were 0.498 (OR =0.498, 95% CI: 0.251-0.989, P<0.05) and 6.067 (OR =6.067, 95% CI: 1.183-31.102, P<0.05) times higher in low-risk children with CT+TT mutant genotypes than in those with CC wild genotypes, respectively. Furthermore, the risk of mucosal damage was 1.906 times higher in high-risk children with the CT+TT genotype than in those with the CC genotype (OR =1.906, 95% CI: 1.033-3.518, P<0.05). The MTHFR A1298C genotypes differed in the incidence of liver function damage and gastrointestinal toxic reactions in children with ALL. Nonetheless, no increased risk of liver function impairment nor gastrointestinal reactions in children with the heterozygous mutant (AC)+CC mutation was observed. Advancements in MTHFR genotype testing in children with ALL and the introduction of personalised treatments based on genotype results during HD-MTX chemotherapy will help to predict, prevent, and reduce the occurrence of adverse MTX-related toxic reactions.

Association of Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in breast cancer patients of Bihar: Case-control study

Breast cancer (BC) is the most frequent cancer in women globally and the main cause of cancer-related mortality. MTHFR C677T is a functional polymorphism in the genes encoding a one-carbon metabolism enzyme that affect folate metabolism and may be associated with breast cancer susceptibility. We have conducted a case-control study taking 100 cases of diagnosed breast cancer and 100 healthy control. PCR-RFLP technique was used to detect the genotype of C677T polymorphism in the study population.About 35% of cases had normal genotype(C677C), 49% had the genotype C677T &amp; rest 16% had the genotype T677T for MTHFR. Among control the frequency of C677C genotype was 55% C677T was 40% &amp; T677T was 5%. C677T &amp; T677T MTHFR genotype were more common in case as compared to control [χ2 (2, N = 200) = 11.12, p = 0.004]. T allele frequency was significantly higher in case (40%) as compared to control (5%) [χ2 (1, N = 400) = 10.91, p = 0.001]. Cases with MTHFR 677TT genotype had a significantly higher risk of BC than 677CC individual [OR=1.64 (1.03 to 2.10)] and increasing T-allele was significant in BC [OR=1.07 (0.71 to 1.33)] (P for trend = 0.04).C677T of MTHFR gene has a strong correlation with breast cancer in the studied population and can be used as a prognostic marker for the development of breast cancer.

[Association of small dense low-density lipoprotein cholesterol with H-type hypertension and MTHFR gene polymorphism].

To investigate the expression of small dense low-density lipoprotein cholesterol (sdLDL-C) in patients with H-type hypertension and its association with H-type hypertension and methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms. The retrospective study method was used,and a total of 207 hospitalized hypertensive patients (76 males and 131 females, aged 40-82 years, median age 66 years) admitted to the Zibo First Hospital from March 2021 to March 2022 were enrolled in this study. The levels of homocysteine (Hcy), sdLDL-C, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglyceride (TG) and lipoprotein (a) [Lp(a)] were measured. The patients were divided into H-type hypertensive group (n=105, 40 males and 65 females) and non-H-type hypertensive group (n=102, 36 males and 66 females) according to Hcy levels. The C677T polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene was detected in each group. Logistic regression analysis was performed for the related factors of H-type hypertension. The serum sdLDL-C levels were (0.92±0.31) and (0.65±0.28) mmol/L in H-type hypertension group and non-H-type hypertension group, respectively. The sdLDL-C levels in H-type hypertension group were significantly higher than those in non-H-type hypertension group (t=6.500, P<0.01). There was no significant difference in the serum sdLDL-C levels between males and females in H-type hypertension group (t=-1.543, P=0.129). The CC, CT, TT genotypes and C and T allele frequencies of MTHFR C677T in H-type hypertension group were significantly different from those in non-H-type hypertension group (P<0.05). The Hcy and sdLDL-C levels in different genotypes of MTHFR in H-type hypertension group were significantly different (H=12.742, P=0.002; F=3.345, P=0.042). Among them, Hcy levels were higher in TT genotype than in CT and CC genotypes, respectively (Z=-28.099, P=0.003; Z=-16.112, P=0.040), and sdLDL-C levels were higher in TT genotype than in CC genotype (t=-2.587, P=0.012). Logistic regression analysis showed that age, sdLDL-C, and MTHFRC677T TT genotypes were associated with the development for H-type hypertension. In conclusion, the level of sdLDL-C is associated with MTHFR gene polymorphisms and may be associated with the development of H-type hypertension.