凝血酶激活纤溶抑制物基因CPB2单核苷酸多态性与不明原因复发性流产的关系

Relationship between polymorphisms of thrombin-activatable fibrinolysis inhibitor gene CPB2 and unexplained recurrent spontaneous abortion

目的 探讨温州地区女性凝血酶激活纤溶抑制物(TAFI)的基因羧肽酶B2(CPB2)单核苷酸多态性与不明原因复发性流产(URSA)的相关性.方法 采集就诊的96例URSA患者(URSA组)和103例同期常规体检、有正常妊娠和生育史、无自然流产史的生育期妇女(对照组)的外周血,提取DNA后应用目标区域捕获测序法检测两组CPB2单核苷酸多态性,并采用飞行时间质谱验证.比较两组基因型和等位基因频率,并分析连锁不平衡性以及位点与血栓指标的相关性.结果 URSA组rs3742264等位基因A和rs9316179等位基因C频率均低于对照组(19.8%vs 33.5%、20.3%vs 33.5%),经Bonferroni法和FDR法多重检验校正,差异均有统计学意义(均P<0.05).URSA组基因型频率rs3742264 GA 35.4%、AA 2.1%和rs9316179 GT 36.5%、TT 2.1%,分别低于对照组rs3742264 GA 53.4%、AA 6.8%和rs9316179 GT 53.4%、TT 6.8%,基因型分布差异均有统计学意义(均P<0.05).连锁不平衡分析表明,rs2296642-rs7337140(D'=0.91,r2=0.83)和rs3742264-rs9316179(D'=1,r^2=0.98)为强连锁不平衡(D'>0.9,r^2>0.33).URSA组基因型组合rs3742264-rs9316179 GGTT频率显著高于对照组(61.5%vs 39.8%,OR=2.411,95%CI:1.364-4.263,χ^2=9.318,P<0.05).URSA组rs3742264 GG携带者血小板最大聚集率(PAgT)中PAgT(ADP)均显著低于rs3742264 GA和AA携带者(均P<0.05).rs3742264不同基因型间FIB、D-Dimer和PAgT(AA)的差异均无统计学意义(均P>0.05).结论 温州地区URSA人群存在CPB2基因遗传易感性,rs3742264等位基因A是URSA保护等位基因,rs3742264基因型间PAgT(ADP)具有显著差异,rs3742264等位基因A可维持正常血浆TAFI水平和血小板功能,有利于正常妊娠.

Objective To explore the relationship between polymorphisms of thrombin-activatable fibrinolysis inhibitor gene CPB2 and the unexplained recurrent spontaneous abortion(URSA).Methods Peripheral blood samples were collected from 96 URSA women(URSA group)and 103 normal pregnant women(control group).The alleles of CPB2 gene were analyzed by target sequence capture combined with high-throughput sequencing technique,and identified by MassARRAY system in all samples.The frequency distribution of alleles and genotypes in each group,and the linkage disequilibrium of alleles were analyzed.Results After Bonferroni and false discovery rate correction,the allele frequency distributions of rs3742264 allele A and rs9316179 allele C in URSA group were significantly lower than those in control group(19.8%vs 33.0%,20.3%vs 33.5%;both P<0.05).There were significant differences in genotype distributions of rs3742264 and rs9316179 between the URSA group and control group(P<0.05).Linkage disequilibrium analysis showed that rs2296642-rs7337140(D'=0.91,r2=0.83)and rs3742264-rs9316179(D'=1,r^2=0.980)had strong linkage disequilibrium(D'>0.9,r^2>0.33)。The combined genotype rs3742264-rs9316179 GGTT(D'>0.9,r2>0.33)was significantly associated with URSA(61.5%vs 39.8%,OR=2.411,95%CI:1.364-4.263,χ^2=9.318,P<0.05).URSA subjects with rs3742264 GG had lower PAgT(ADP)levels compared to those with the GA or AA genotype(P<0.05)However,there were no significant differences in FIB,D-Dimer and PAgT(AA)among different genotypes of rs3742264(P>0.05).Conclusion The SNPs of CPB2 may contribute to the susceptibility of URSA in pregnant women.The rs3742264 allele A may display a protective effect against URSA.Different genotypes of rs3742264 may be associated with platelet aggregation.The allele A of rs3742264 may maintain normal plasma TAFI level and platelet function,which is beneficial to normal pregnancy.