亚甲基四氢叶酸还原酶、凝血因子V和凝血酶原基因多态性与原因不明复发性早期流产的关系

目的探讨亚甲基四氢叶酸还原酶（MTHFR）基因C677T突变、凝血因子V（FV）基因G1691A突变和凝血酶原（PT）基因G20210A突变与原因不明复发性早期流产（URESA）的关系。方法应用聚合酶链反应．限制性片段长度多态性（PCR-RFLP）技术分析112例URESA患者（病例组）和100例健康妇女（对照组）MTHFR、FV和PT3种基因多态性。结果（1）MTHFR基因的T／T基因型和T等位基因频率,病例组[分别为38．4％（43／112）和59．8％（134／224）]高于对照组[分别为18．0％（18／100）和43．0％（86／200）],两组分别比较,差异均有统计学意义（P＜0．01）。病例组与对照组比较,T／T基因型者发生URESA的相对风险增加（OR=2．8390,95％CI为1．5022～5．3661）。（2）病例组和对照组妇女Fv基因和PT基因均为G／G基因型（即正常带型）。结论MTHFR基因C677T位点多态性与URESA发病密切相关,T／T基因型是其发病的危险因素。FV和PT基因的突变率在中国妇女人群中极低。

Relationship between three thrombophilic gene mutations and unexplained recurrent early spontaneous abortion

OBJECTIVE: To explore the relationship of methylenetetrahydrofolate reductase (MTHFR) gene C677T, factor V (FV) gene G1691A and prothrombin (PT) gene G20210A polymorphisms to unexplained recurrent early spontaneous abortion (URESA). METHODS: One hundred and twelve patients with URESA and 100 women with at least 1 normal pregnancy and without any miscarriage were analyzed for MTHFR, FV and PT gene polymorphisms by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: MTHFR gene T/T genotype and T allele frequencies were increased in URESA patients [38.4% (43/112) and 59.8% (134/224)] versus controls [18.0% (18/100) and 43% (43/100), P<0.01]. The patients carrying T/T genotype had a high risk of URESA (OR=2.8390, 95% CI: 1.5022 - 5.3661). However, FV and PT G20210A mutations were not found either in patients or in controls. CONCLUSIONS: The genetic polymorphisms of MTHFR C677T are associated with URESA. It might indicate a genetic influence on pathogenesis of URESA. FV and PT gene mutations may be rare in Chinese women, and have no significance in URESA.