多囊卵巢综合征糖代谢异常与性激素结合球蛋白基因启动子(TAAAA)n多态性的关系

目的探讨性激素结合球蛋白（SHBG）基因启动子（TAAAA）n重复多态与多囊卵巢综合征（PCOS）及其糖代谢异常的关系。方法353名正常育龄妇女为对照组，241例PCOS患者中180例接受口服糖耐量试验、胰岛素释放试验并被分为非胰岛素抵抗（NIR）组、高胰岛素血症（HI）组、异常糖代谢（AGM）组；基因片段分析法检测荧光标记多态片段长度，并测序鉴定其重复次数；比较组间临床及代谢参数、（TAAAA）n多态等位基因及基因型分布。结果（1）PCOS组体重指数、腰臀比、腰围、血压、空腹胰岛素、胰岛素抵抗指数（Homa—IR）、甘油三酯水平高于对照组，AGM组高于HI组、NIR组；胰岛素敏感指数变化相反；组间各参数比较差异均有统计学意义（均P〈0．05）。（2）检测到（TAAAA）6～10次重复5种等位基因、14种基因型，但5种等位基因频率和总基因型分布及各基因型分布PCOS组与对照组比较差异无统计学意义。（3）PCOS糖代谢3组间5种等位基因频率和总基因型分布无统计学差异，但3组间7／9基因型分布不同（χ^2=9．671，P〈0．01），AGM组7／9基因型分布频率明显高于NIR、HI组（χ^2=6，792，P〈0．01；χ^2=6．538，P〈0．05）。结论SHBG基因启动子（TAAAA）n重复多态及其分布与PCOS无明显相关，但（TAAAA）n多态7／9重复基因型与PCOS糖代谢异常发生、进展可能有关。PCOS糖代谢异常可能与肥胖等其他因素相关。故该SHBG基因多态性并不能预测PCOS的高危个体。

Association of ( TAAAA)n repeat polymorphism in promotor of sex hormone-binding globulin gene with glucose metabolic status in patients with polycystic ovary syndrome

Objective To investigate the association of(TAAAA).repeat polymorphism in the promoter of sex hormone-binding globulin(SHBG)gene with glucose metabolic status in patients with polycystic ovary syndrome(PCOS).Methods A total of 353 normal controls and 241 PCOS women were included in this study, and 180 patients with PCOS received oral glucose tolerance test and insulin release test,which were divided into three groups:normal glucose tolerance without hyperinsulinemia(NIR)or with hyperinsulinemia(HI)and abnormal glucose metabolic(AGM)groups.Body mass index(BMI),blood pressure,testosterone(T),blood glucose,insulin,lipids and the area under the curve for glucose and for insulin(AUGC and AUIC),Homa-IR, and insulin sensitivity index(ISI)were measured and calculated;GeneScan method was used to detect and identify (TAAAA)_n alleles and genotypes.Results BMI,waist hip ratio(WHR),waist circumference,blood pressure, Homa-IR,triglyceride level were all higher in PCOS than those in control,and higher in AGM than those in HI group and NIR group;ISI acted vice versa(all P<0.05).Five(TAAAA)n alleles containing 6-10 repeats and 14 genotypes were present in PCOS and control groups.Among three glucose metabolic groups in PCOS,there was no significant difference in the distribution of alleles and genotypes except 7/9 genotype distribution had higher frequency in AGM group than those in NIR and HI group(x~2=6.792,P<0.01;X~2=6.538,P<0.05). Conclusion The repeat number(alleles),genotypes and their distributions appear to be not related with PCOS, 7/9 repeats genotype's distribution may be closely related to glucose metabolism in PCOS,and other factors such as obesity may play some roles.SHBG polymorphism is not a good indicator to find the individual at high risk for PCOS.