RESUMO
Objective To investigate the distribution of methyleneterahydrofolate reductase (MTHFR) C677T gene polymorphisms and serum homocysteine (Hcy) levels in pregnant women. Method A total of 2 066 women with singleton pregnancies undergoing prenatal examinations in the Maternity and Child Health Care Hospital of Huzhou from January 2017 to October 2017 were recruited for the study.The MTHFR C677T genotype was detected by PCR-fluorescence probing, and the serum Hcy levels were detected by the cyclic enzyme method. According to the MTHFR C677T genotype detection analysis, the results were divided into the CC-type, CT-type, and TT-type groups. Statistical analyses were performed using the Hardy-Weinberg genetic equilibrium test, chi-square test, variance analysis, and t test. Result Among the 2066 pregnant women, the CC, CT, and TT genotype frequencies for the MTHFR C677T gene were 39.35%,46.52%,and 14.13%,respectively.The Cand T allele frequencies were 62.61% and 37.39%, respectively. The statistical significance values for the Shanxi, Zibo, Shanghai, Suzhou, Shangzhi, Xi'an, Huizhou, and Nanning areas were as follows: χ2=161.999, 166.083; 111.005, 112.517; 416.146, 441.245;14.262,14.23;36.368,35.871;199.498,204.771;19.641,16.377;and 66.79,61.593,respectively;P<0.05. The level of serum Hcy was(7.48±2.20)μmol/L,and the abnormal rate was 3.53%.The level of serum Hcy and the abnormal rate among the 3 genotypes were distributed as follows: TT>CT>CC. The difference was statistically significant(F=120.968, χ2=52.572, P=0.000). Conclusion The distribution of genotype frequencies for MTHFR C667T in 2 066 pregnant women was different in various geographical regions.The level of serum Hcy was associated with the MTHFR C677T gene. Observing MTHFR C677T gene polymorphisms and serum Hcy levels is helpful for monitoring and guiding folic acid supplementation during pregnancy,and establishing reasonable individual health preventive measures.It is an important method to improve the quality of life of the offspring and the family happiness index.