遗传-环境效应对学龄期女孩唾液睾酮影响的双生子研究

Genetic and environmental effects on salivary testosterone in school-aged girls:a twin study

目的探讨遗传和环境因素对学龄期女孩唾液睾酮水平的影响,以及年龄在其中的作用。方法以2006年-2007年北京中小学募集的6-12岁双生子女孩为研究对象,共获得双生子78对(同卵双生63对,异卵双生15对),平均年龄为8.92±1.90岁。以DNA进行卵性鉴定,酶联免疫法测量唾液睾酮水平,拟合结构方程模型估计唾液睾酮遗传度,并检验年龄的作用。结果学龄期女孩唾液睾酮水平从6岁时的17.47pg/ml增长为12岁时的63.98 pg/ml,其中9-11岁增长迅速;AE-age模型为最适模型,年龄作用占总方差的34.54%,遗传和环境方差分别占41.50%和23.96%。扣除年龄作用,学龄期女孩唾液睾酮遗传度为63.4%。结论学龄期女孩唾液T水平受到遗传和环境因素的共同作用,遗传效应尤为显著;年龄对其唾液T水平有重要影响。

Objective ： To explore the genetic and environmental influence on salivary testosterone in school - aged girls, and the effect of age. Methods ： Seventy eight pairs female twins aged 6 to 12 were elected from the recruited twins, including monozygotic 63 pairs, dizygotic 15 pairs. Average aged was 8.92±1.90 years old. Zygosity was determined by DNA. Saliva samples were assayed for testosterone by enzyme immunoassay （EIA）. The structural equation models were fitted to estimate the heritability of salivary testosterone. Results ： Salivary T rose with age in school - aged girls. The best fitted model was AE - age model, in which age accounted for 34. 54% of variance, the estimates of a and e were 41.50% and 23.96% of the total variance, respectively. The heritability of salivary testosterone was 63.4% by assuming the causes of variation do not vary with age. Conclusion ： Salivary T were commonly effected by genetic and environment in school - aged girls, especially genetic. Age was an important factor influencing girls＇ salivary T level.