Association of MTHFR C677T, MTHFR A1298C and MTRR A66G Polymorphisms with Birth Defects in Southern China

: To investigate the association of MTHFR C677T, MTHFR A1298C and MTRR A66G polymorphisms with birth defects in southern Chinese population. Genotyping was performed by Fluorescence Quantitative Analyzer using the Sequencing Reaction Universal Kit. Association analysis method was used to explore the relationship between genetic polymorphisms in MTHFR , MTRR gene and birth defects. Our results showed that serum folic acid level of genotype TT in MTHFR C677T was significantly lower than other genotypes, while homocysteine level significantly higher compared with CC and CT ( P < 0.05). In addition, genotype GG in MTRR A66G might also promote homocysteine accumulation ( P < 0.05). Results of logistic regression represented that MTHFR C677T, MTHFR A1298C, and MTRR A66G polymorphisms were not important or independent risk factors for predicting birth defects. Besides, genotype distribution of MTHFR C677T was significantly different in normal and abnormal pregnancy population, and genotype TT might affect folic acid metabolism and promote homocysteine accumulation. However, MTHFR C677T, MTHFR A1298C, and MTRR A66G polymorphisms were not critical or independent risk factors for predicting birth defects in this study. the dosage of folic acid 14) . In this study, we ex-plored the relationship between the key enzyme genes MTHFR and MTRR of folic acid metabolism and birth defects. Our results showed the genotype distribution of MTHFR C677T, MTHFR A1298C and MTRR A66G polymorphisms was significantly different between normal and abnormal pregnancy populations in southern China. Genotype TT in MTHFR C677T might not be conducive to folic acid metabolism and normal pregnancy, while promoting homocysteine accumulation. How-ever, the diverse genotypes of MTHFR C677T, A1298C and MTRR A66G polymorphisms were not independent risk factors for predicting birth defects.