scholarly journals Genotype Prevalence and Allele Frequencies of 5,10-Methylenetetrahydrofolate Reductase (MTHFR) C677T and A1298C Polymorphisms in Italian Newborns

2009 ◽  
Vol 40 (12) ◽  
pp. 732-736 ◽  
Author(s):  
Bruno Zappacosta ◽  
Lucio Romano ◽  
Silvia Persichilli ◽  
Luigi A. Cutrone ◽  
Mirella Graziano ◽  
...  
2010 ◽  
Vol 29 (2) ◽  
pp. 111-119 ◽  
Author(s):  
Chuanfei Chen ◽  
Yik-Yuen Gan

The cystathionineβ-synthase (CBS) 844ins68 polymorphism, methionine synthase (MS) A2756G SNP, and 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T SNP are associated with homocysteine (Hcy) level in humans. Elevated Hcy level is considered a risk factor for atherosclerotic diseases among Asian populations. Therefore, the three polymorphisms may vary the risk for developing such diseases in Singaporeans. In this study, the three polymorphisms were determined in a group of unrelated healthy Singaporeans (273 Chinese, 127 Indians, and 156 Malays). Regarding allele frequencies, Indians had the highest frequencies of the CBS insertion allele (2.0%) and the MS 2756G allele (26.4%), while Chinese had the highestMTHFR677T allele frequency (27.5%). In addition, theMTHFR677T allele was found significantly lower in Chinese males than in their female counterparts. As the CBS insertion allele was suggested to be associated with lower Hcy level, whereas the MS 2756G allele and theMTHFRT/T genotype were related to higher Hcy level, the MS A/G or G/G genotype and theMTHFRT/T genotype were considered double genetic risk factors for elevated Hcy level. The frequency of such double genetic risk was 0.7% (4 subjects) in the total population consisting of 3 Chinese (1.1%) and 1 Malays (0.6%). NoMTHFRT/T genotype was found in Indians. Such results suggested that Chinese could have higher Hcy levels than Malays while the situation for Indians was complicated. Since human Hcy levels are also affected by environmental factors, further studies are required to better evaluate the association between these three polymorphisms and Hcy levels and/or disease susceptibilities in Singaporeans.


2022 ◽  
Author(s):  
Xiaoying Yu ◽  
Le Diao ◽  
Baoying Du ◽  
Ying Wang ◽  
Xiaoqin Xv ◽  
...  

Abstract Backgroud: Folic Acid (FA) may contribute to the development of gestational diabetes mellitus (GDM), but existing studies are inconsistent. We examined the genotype distributions and allele frequencies of methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G polymorphisms of pregnant women in China, and compared the effects of individualized folate supplementation and traditional FA supplementation on GDM.Methods: The genotype distributions and allele frequencies of MTHFR C677T, A1298C and MTRR A66G polymorphisms in 968 pregnant women (case group) were tested. FA metabolism was ranked at four levels, and then pregnant women of different levels are supplemented with different doses of FA at different periods. The case group was followed up for pregnancy complications and compared with 1,940 pregnant women traditionally supplemented with FA in the same hospital (control group).Results: The allele frequencies of MTHFR C677T were 63.3% (C) and 36.7% (T), those of MTHFR A1298C were 79.3% (A) and 20.7% (C), and those of MTRR A66G were 75.0% (A) and 25.0% (G). Compared with control group, the incidence of GDM in the case group were significantly lower, especially in high-risk pregnant women after FA supplementation.Conclusion: Traditional FA supplementation based on personal habits is controversial, but the use of polymorphisms of genes to clarify the FA metabolism of pregnant women, appropriate, timely and accurate supplementation of FA can effectively reduce gestational diabetes, especially for high-risk pregnant women.


2021 ◽  
pp. 112067212110006
Author(s):  
Manuel Marques ◽  
Francisco Alves ◽  
Miguel Leitão ◽  
Catarina Rodrigues ◽  
Joana Tavares Ferreira

The role of polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene in retinal vein occlusion (RVO) is a theme of discussion since the first reports of RVO in patients with MTHFR C677T mutation and without classic acquired risk factors for retinal vascular disease. The association between MTHFR polymorphisms and RVO has been studied over the last 20 years producing conflicting results. This review aims to summarize the literature concerning the role MTHFR polymorphisms as risk factors for RVO.


F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 1034
Author(s):  
Modou Jobe ◽  
Mary Ward ◽  
Bakary Sonko ◽  
Abdul Khalie Muhammad ◽  
Ebrima Danso ◽  
...  

Introduction: Emerging evidence links a functional polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene (rs1801133) with hypertension in adults. This variant reduces the affinity of MTHFR for its cofactor flavin-adenine dinucleotide (FAD) which is derived from riboflavin. Previous work has demonstrated a blood pressure (BP)-lowering effect of riboflavin in Irish adults with the MTHFR 677TT variant. We hypothesize that the almost-universal severe riboflavin deficiency seen in rural Gambia mimics the BP phenotypic effect of the TT variant and exacerbate the effect of the CT variant. We will test this in a randomised, placebo-controlled trial, whether intervention with riboflavin can decrease BP in adults in rural Gambia. Methods: This is a phase 2 recall-by-genotype randomised single-blind placebo-controlled riboflavin supplementation trial. We will use the Keneba biobank to recruit approximately 102 individuals aged between 18-70, previously genotyped for the MTHFR C677T polymorphism and identified as carrying the T allele; these individuals will be age- and sex-matched to a similar number of homozygotes for the C allele. The participants will be randomised to a 16-week supplementation trial of 5 mg/day riboflavin or placebo, supplied every 14 days. The primary outcome, BP, will be measured at baseline and at weeks 8 and 16. Blood samples, collected at baseline and week 16, will be analysed for riboflavin, homocysteine, red cell folate, cobalamin (vitamin B12) and pyridoxine (vitamin B6). Discussion: The study will evaluate the role of riboflavin supplementation in BP control within a population with high levels of riboflavin deficiency and will test a possible gene-nutrient interaction with the MTHFR C677T polymorphism. If improvements in BP are observed in this study, and proven in subsequent large-scale interventions, riboflavin could offer a cost-effective, safe and accessible option for the  prevention and control of hypertension in this population. Trial registration: ClinicalTrials.gov Identifier NCT03151096. Registered on 12 May 2017.


2021 ◽  
Vol 12 ◽  
Author(s):  
Hao Meng ◽  
Shaoyan Huang ◽  
Yali Yang ◽  
Xiaofeng He ◽  
Liping Fei ◽  
...  

Background: Since the 1990s, there have been a lot of research on single-nucleotide polymorphism (SNP) and different diseases, including many studies on 5,10-methylenetetrahydrofolate reductase (MTHFR) polymorphism and essential hypertension (EH). Nevertheless, their conclusions were controversial. So far, six previous meta-analyses discussed the internal relationship between the MTHFR polymorphism and EH, respectively. However, they did not evaluate the credibility of the positive associations. To build on previous meta-analyses, we updated the literature by including previously included papers as well as nine new articles, improved the inclusion criteria by also considering the quality of the papers, and applied new statistical techniques to assess the observed associations. Objectives: This study aims to explore the degree of risk correlation between two MTHFR polymorphisms and EH. Methods: PubMed, EMBASE, the Cochrane Library, CNKI, and Wan Fang electronic databases were searched to identify relevant studies. We evaluated the relation between the MTHFR C677T (rs1801133) and A1298C (rs1801131) polymorphisms and EH by calculating the odds ratios (OR) as well as 95% confidence intervals (CI). Here we used subgroup analysis, sensitivity analysis, cumulative meta-analysis, assessment of publication bias, meta-regression meta, False-positive report probability (FPRP), Bayesian false discovery probability (BFDP), and Venice criterion. Results: Overall, harboring the variant of MTHFR C677T was associated with an increased risk of EH in the overall populations, East Asians, Southeast Asians, South Asians, Caucasians/Europeans, and Africans. After the sensitivity analysis, positive results were found only in the overall population (TT vs. CC: OR = 1.14, 95% CI: 1.00–1.30, Ph = 0.032, I2 = 39.8%; TT + TC vs. CC: OR = 1.15, 95% CI: 1.01–1.29, Ph = 0.040, I2 = 38.1%; T vs. C: OR = 1.14, 95% CI: 1.04–1.25, Ph = 0.005, I2 = 50.2%) and Asian population (TC vs. CC: OR = 1.14, 95% CI: 1.01–1.28, Ph = 0.265, I2 = 16.8%; TT + TC vs. CC: OR = 1.17, 95% CI: 1.04–1.30, Ph = 0.105, I2 = 32.9%; T vs. C: OR = 1.10, 95% CI: 1.02–1.19, Ph = 0.018, I2 = 48.6%). However, after further statistical assessment by FPRP, BFDP, and Venice criteria, the positive associations reported here could be deemed to be false-positives and present only weak evidence for a causal relationship. In addition, when we performed pooled analysis and sensitivity analysis on MTHFR A1298C; all the results were negative. Conclusion: The positive relationships between MTHFR C677T and A1298C polymorphisms with the susceptibility to present with hypertension were not robust enough to withstand statistical interrogation by FPRP, BFDP, and Venice criteria. Therefore, these SNPs are probably not important in EH etiology.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Mohamed A. El-Hadidy ◽  
Hanaa M. Abdeen ◽  
Sherin M. Abd El-Aziz ◽  
Mohammad Al-Harrass

Objective. Several studies with contradictory results from different cultures about association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in schizophrenia and bipolar disorders. Little is known about this association in Arab culture and Egypt. So the present study aimed to assess the association of MTHFR C677T polymorphism in bipolar disorder (BD) and schizophrenia in comparison to control group. The association between MTHFR C677T polymorphism and the age at onset in schizophrenia or BD was also studied.Methods. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) were used to examine the genotype and allele frequencies of MTHFR C677T polymorphism in 149 healthy subjects and 134 bipolar and 103 schizophrenia patients.Results. In BD and schizophrenia, there was a higher prevalence of MTHFR C677T polymorphism than healthy subjects. Earlier age at onset was found in patients with BD, carrying one copy of the T allele or CT genotypes but not in patients with schizophrenia.Conclusion. The present findings suggest that the MTHFR C677T polymorphisms are likely to be associated with the risk of developing BD and schizophrenia and influence the age at onset of BD but not the age at onset of schizophrenia.


2012 ◽  
Vol 48 ◽  
pp. S128
Author(s):  
L. Delgado-Plasencia ◽  
S. González-García ◽  
V. Medina-Arana ◽  
H. Álvarez-Arguelles Cabrera ◽  
E. Salido-Ruiz ◽  
...  

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