中国北方汉族男性SHBG基因启动子(TAAAA)n多态分布及其与有氧能力的关联性研究

Distributions of the (TAAAA)n Polymorphism in the Promoter of SHBG Gene and its Association with Aerobic Endurance Phenotype in Men of Han Nationality in Northern China

目的:探讨性激素结合球蛋白(SHBG)基因(TAAAA)n多态在中国北方汉族男性中的分布特征及其与有氧能力的关联性。方法:102名中国北方汉族健康青年男性受试者进行为期20周、每周3次5000米匀速跑的有氧耐力训练,训练前后分别测试VO2max和RE相关生理指标。使用GeneScan和测序方法分析SHBG(TAAAA)n多态等位基因和基因型。进行该多态与有氧能力初始值和耐力训练效果的关联性分析。结果:(1)在中国北方汉族男性中观察到(TAAAA)6～10次重复等位基因和11个基因型。其中,9次重复等位基因分布频率最高,10次重复等位基因分布频率最低;(2)当分别以7、8和9次重复作为分割点划分基因型时,发现长链组VO2max相关指标训练前初始水平平均值均大于短链组。其中,按7次重复划分时,≥7次基因型携带者训练前VO2max和VO2max时的VE初始值均有高于<7次携带者的趋势(P均为0.06);(3)不同基因型组间VO2max和RE各指标的耐力训练敏感性无显著性差异。结论:SHBG基因(TAAAA)n多态与男性有氧能力指标初始水平可能存在一定的关联性,推测重复次数较多的等位基因携带者的有氧能力初始水平较好,但与耐力训练敏感性无关联。

Objective To investigate the distribution characteristics of （TAAAA）n polymorphism in the sex hormone binding globulin （SHBG） gene and its relationship with aerobic capacity. Methods One hundred and two healthy young men of Han nationality in northern China took part in this study. They ran 5000m three times per week for 20 weeks. VO2max and RE were measured before and after 20-week training. GeneScan method was used to identify the repeat alleles and genotypes of （TAAAA）n polymorphism. The association of the polymorphism with initial endurance performance and the response to endurance training was analyzed. Results （1） Five alleles containing （TAAAA）6-10 repeat alleles and 11 genotypes with 15 possibilities were observed in the subjects. The （TAAAA）9 was the most common allele and （TAAAA）10 was relatively rare. （2）The successive cut-point analysis showed that the initial mean value of VO2max in longer genotype carrier group were higher than that in shorter genotype carriers group. There was a tendency of higher initial VO2max and VE in 〈7 genotype group as compared with that in 〉17 genotype group（P=0.06 and P=0.06, respectively）. （3） The VO2max and RE after 20-week training revealed no significant difference in carrier groups with different genotype. Conclusion This study suggests that a possibility of association of SHBG （TAAAA）n polymorphism with the initial aerobic capacity in Chinese men of Han nationality exists; however, the SHBG （TAAAA）n polymorphism has no association with the sensibility to endurance training.