Geographical Distribution of MTHFR C677T, A1298C and MTRR A66G Gene Polymorphisms in China: Findings from 15357 Adults of Han Nationality

Abstract

BackgroundMethylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G polymorphisms are important genetic determinants for homocysteine (Hcy) levels, and are associated with several disorders. These polymorphisms are heterogeneously distributed worldwide. Our objective was to explore the geographical distributions of these polymorphisms in China.Methodologies15357 healthy adults were recruited from 10 regions. Buccal samples were collected and genomic DNA was isolated. Genotyping was performed using the fluorogenic 5′-nuclease assay.Principal FindingsThe prevalence of the three polymorphisms among different populations from China varied significantly and showed apparent geographical gradients. For MTHFR C677T, the frequencies of the 677T allele and the 677TT genotype were significantly higher among northern populations and ranged from the lowest values (24.0% and 6.4%, respectively) in Hainan (southern) to the highest values (63.1% and 40.8%, respectively) in Shandong (northern). For MTHFR A1298C, the 1298C allele and the 1298CC genotype frequencies were significantly higher among southern populations and increased from low values (13.1% and 1.4%, respectively) in Shandong to high values (25.7% and 6.7%, respectively) in Hainan. For A66G, the 66G allele and the 66GG genotype frequencies increased from lower values (23.7% and 5.4%, respectively) in Shandong to higher values (29.2% and 8.6%, respectively) in Hainan. The overall frequency of the 677T allele, 677TT genotype, 1298C allele, 1298CC genotype, 66G allele and 66GG genotype in the Chinese Han population was 45.2%, 23.2%, 18.6%, 3.9%, 25.7%, and 6.6%, respectively. No gender differences were found in the prevalence of both the MTHFR C677T and MTRR A66G polymorphisms.ConclusionsThis study indicates that there are marked geographical variations in the prevalence of the three polymorphisms among Chinese Han populations. Our baseline data may be useful for future researches in related fields.

Association between Decreased Plasma Folate Levels and MTHFR C677T, and MTRR A66G Gene Polymorphisms as Determinants for Elevated Total Homocysteine Concentrations in Pregnant Women

“…The results were consistent with the previous studies [24,43,44]. Because the prevalence (19%) of 677TT genotype is high in China, the risk of exposure to plasma folate deficiency, resultant hyperhomocysteinemia, and adverse pregnancy outcome may elevate [45][46][47].…”

Association between methionine synthase reductase A66G polymorphism and primary infertility in Chinese males

“…All polymorphisms were in Hardy-Weinberg equilibrium (P = 0.922, 0.797, 0.512, and 0.333, respectively). Allelic frequencies for fertile men with the 66GG and 677TT variations in this study were similar to those in healthy Chinese men (Yang et al, 2013). The MTRR A66G, MTHFR C677T, MTHFR A1298C, and MS A2756G polymorphism data, according to our case-control analysis, showed no significant differences for individuals with infertility (P > 0.05).…”

The Role of Folate Dependent Genetic Susceptibility in The Risk of Multiple Sclerosis

“…But for MTR A2756G and MTRR A66G polymorphisms, there are not enough studies. Hence, further studies are need to be conducted (Table 1) [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58]. …”