亚甲基四氢叶酸还原酶基因多态性与孕妇子痫前期易感性及新生儿围生结局的关系

The Relationship Between Gene Polymorphism of Methylenetetrahydrofolate Reductase C677T and Pre-eclampsia and Outcomes of Perinatology in Pregnant Women

目的研究亚甲基四氢叶酸还原酶（methylenetetrahydrofolate reductase，MTHFR）基因C677T多态性与孕妇子痫前期易感性及新生儿围生结局的关系。方法选择2013年1月至2014年8月在我院妇产科待产的孕妇120例，其中子痫前期患者组（实验组）和对照组各60例，抽提全血DNA，PCR扩增MTHFR基因片段，经酶切反应后通过凝胶电泳对MTHFRC677T位点的突变进行检测，计算两组孕妇的基因型分布情况，并分析MTHFR基因多态性与孕妇子痫前期的关系，同时跟踪新生儿围生结局并分析其与MTHFR基因突变的关系。结果实验组与对照组的孕妇MTHFRC677T位点多态性的检查结果分别为野生型纯合子型11．67％与23．33％；杂合子突变型45．00％与61．67％；突变型纯合子43．33％与15．00％；T／T基因型的孕妇发生子痫前期的风险是C／C基因型或T／C基因型孕妇的1．86倍（95％CI：1．34～2．57）。不同基因型对应的新生儿平均出生体质量与新生儿评分异常率结果：C／C型的平均出生体质量为3186．2±432．4g，异常新生儿评分率4．76％；C／T型的平均出生体质量为3216．5±512．4g，异常新生儿评分率3．12％；T／T型的平均出生体质量为3078．5±408．6g，异常新生儿评分率5．71％。虽然各组基因型之间的平均出生体质量与异常新生儿评分率结果不同，但差异无统计学意义。结论MTHFRC677T突变是孕妇发生子痫前期的危险因素之一，但与新生儿围生结局无显著相关。

Objective To explore the gene polymorphism distribution of methylenetetrahydrofolate reductase （MTHFR） at C667T site in pregnant women, and analyze its relationship with pre-eclampsia and outcome of perinatology. Methods Venous blood was drawn from 120 pregnant women in our hospital between January 2013 and August 2014. There were 60 cases of pre-eclampsia（experimental group） and 60 normal pregnant women （control group）. The whole blood DNA was extracted, MTHFR gene segment was amplified with PCR, and after treatment of restriction enzyme polyacrylamidedel electrophoresis was used to analysis the mutation of MTHFR at C667T site. The genotype frequencies were calculated by gene counting in pregnant women to evaluate the relationship of MTHFR C677T polymorphism with pre-eclampsia. The outcomes of perinatology were traced and the association between the outcomes and MTHFR mutation was analyzed. Results The polymorphism of MTHFR C667T in the experimental group and control group were as follows： 11.67% and 23.33% were wild genotype, 45.00% and 61.67% were heterozygous mutant, and 43.33% and 15.00% were homozygous mutant. Compare with that of pregnant women with C/T and C/C genotype, the relative risk（OR） of pregnant women with the T/T genotype for pre-eclampsia was 1.86 （95 % CI：I. 34-2.57 ）. The average body mass at birth and abnormal rate of neonatal score in different genotypes were as follows ： the average body mass at birth and abnormal rate of neonatal score were 3186.2±432.4 g and 4.76% in the perinatal infants of C/C genotype, 3216.5 ±512.4 g and 3.12% in those of C/T genotype, and 3078.5±408.6 g and 5.71% in those of T/T genotype. The average body mass at birth and abnormal rate of neonatal score in different genotypes were different, but there was no significance among them. Conclusion The mutation of MTHFR C677T is a risk factor correlated with pre-eelampsia, and there is no association between MTHFR C677T polymorphism and outcomes of perinatology.