摘要目的 分析叶酸代谢相关基因的多态性与胎儿先天缺陷的相互关系,探讨遗传性因素对胎儿先天缺陷的影响.方法 回顾性分析132例不良妊娠孕妇(病例组)及同期就诊的150例正常妊娠孕妇(对照组)5,10-亚甲基四氢叶酸还原酶(MTHFR)基因的C677T、A1298C位点和甲硫氨酸合成酶还原酶(MTRR)基因A66G位点的基因型和基因频率,及其血清叶酸、维生素B12(Vit B12)和同型半胱胺氨酸(HCY)水平之间的差异.结果 病例组的血清叶酸与Vit B12呈正相关,与HCY呈负相关,仅有胎儿骨骼系统缺陷孕妇(6例)的HCY高于对照组(t=3.409,P＜0.05).病例组MTHFR基因C677T、A1298C位点和MTRR基因A66G位点的基因型频率与对照组比较,差异无统计学意义(P＞0.05);以上三个基因位点的C/T、A/C、A/G基因频率与对照组比较,差异均无统计学意义(P＞0.05).病例组和对照组MTHFR基因A1298C位点与C667T位点的不同基因型组合差异无统计学意义(P＞0.05),未见有协同作用.结论 孕妇的叶酸代谢相关MTHFR和MTRR基因的多态性对母体相应的代谢产物水平变化有一定影响,但其与胎儿先天缺陷发生的遗传学机制的相关性有待更多的大样本研究结果深入探讨.

abstractsObjective To investigate the relationship between folate metabolism-related gene polymorphism and fetal congenital defects,and discuss the effect of genetic factors on fetal congenital defects.Methods Retrospective analysis was used to investigate the genotype and gene frequency of 5,1O-methylenetetrahydrofolate reductase (MTHFR) C677T,A1298C gene loci and ethionine synthase reductase (MTRR) A66G gene locus in 132 cases of adverse pregnancy pregnant women (case group) and 150 cases normal pregnant women (control group) at the same period.The statistical differences were analyzed between the levels of their serum folate,vitamin B12 (Vit B12) and homocysteine (HCY).Results In the serum of case group,folate was positively correlated with Vit B12,and was negatively correlated with HCY,only HCY of skeletal system defects(6 cases) was higher (t =3.409,P ＜ 0.05).Comparing genotypes frequency of the MTHFR C677T,A1298C gene loci and MTRR A66G gene locus in case group with control group,the difference above was not statistically significant (P ＞ 0.05).In these three gene loci C/T,A/C and A/G allele frequency with the control group,the difference above was not statistically significant (all P ＞ 0.05).Different genotype combinations of MTHFR C667T and A1298C gene loci in control groups had no statistically different from the control group (P ＞ 0.05),and there was no synergy.Conclusions Maternal folate metabolism-related MTHFR and MTRR genes polymorphisms can affect the metabolic products levels accordingly.However,the correlation between the changes and the genetic mechanism of fetal congenital defects needs more large samples study in depth.