原因不明复发性流产患者细胞毒性T淋巴细胞抗原4基因第一外显子49位点A/G基因多态性研究

目的探讨细胞毒性T淋巴细胞抗原4（CTLA-4）基因第一外显子49位点A／G基因多态性与原因不明复发性流产（URSA）发病的相关性。方法采用PCR限制性片断长度多态性方法（PCR-RFLP）,检测168例URSA患者（URSA组）和117例有正常生育史的妇女（对照组）CTLA-4基因第一外显子49位点A／G多态性,并比较等位基因G／A、基因型AA／AG／GG、表型A＋（AA＋AG）／G＋（GG＋AG）分布频率的差异。结果URSA组等位基因G的出现频率为68．4％（230／336）,对照组为59．4％（139／234）,两组比较,差异有统计学意义（P〈0．05）;基因型GG的出现频率URSA组为48．8％（82／168）,对照组为33．3％（39／117）,两组比较,差异也有统计学意义（P〈0．05）;URSA组基因型AG、基因表型A＋（AA＋AG）的频率分别为39．3％（66／168）、51．2％（86／168）,对照组分别为52．1％（61／117）、66．7％（78／117）,两组比较,差异均有统计学意义（P〈0．05）。结论CTLA-4基因第一外显子49位点A／G多态性与URSA的发生存在相关性,并可能参与流产发生的免疫病理过程。

A/G polymorphism at position 49 in exon 1 of CTLA-4 gene in Chinese women with unexplained recurrent spontaneous abortion

Objective To investigate whether A/G polymorphism at position 49 in exon 1 of cytotoxic T lymphocyte antigen-4 (CTLA-4) gene confers the susceptibility to unexplained recurrent spontaneous abortion in Chinese population. Methods One hundred and sixty-eight restrictive Chinese women with unexplained recurrent spontaneous abortion (URSA) and 117 women with normal pregnancy as control were included in this study. Polymerase chain reaction restrictive fragment length polymorphism (PCR-RFLP) was used to detect the polymorphism at position 49 in exon 1 of CTLA-4 gene. The frequency of alleles G/A, genotypes AA/AG/GG and phenotypes A+ (AA+AG) /G+ (GG+AG) of CTLA-4 were compared between URSA patients and controls. Results The different distributions of alleles G/A, genotype AA/AG/GG and phenotypes A+/G+ of CTLA-4 were observed between URSA patients and controls. The frequencies of both G allele [68.4% (230/336) vs 59.4%(139/234), P<0.05] and GG genotype [48.8% (82/168)vs 33.3%(39/117), P<0.05] were significantly higher in URSA group than that in control group, while the frequencies of AG genotype [39.3%(66/168) vs 52.1%(61/117), P<0.05] and A+ (AA+AG) phenotype [51.2% (86/168)vs 66.7%(78/117), P<0.05] were significantly lower in URSA group than that in control group. Conclusions The results suggest that A/G polymorphism in exon-1 of CTLA-4 might confer the susceptibility to RSA in Chinese women.