不同发育期双生子皮褶厚度及体成分分析

Skinfold thickness and body composition in twins of different development periods

目的分析遗传与环境因素不同发育期双生子皮褶厚度及体成分的作用特点。方法测量376对6～18岁同性别双生子(同卵245对,异卵131对)肱三头肌、肩胛下皮褶厚度,用长岭和Brozek公式估算体成分;用Mx软件拟合最佳模型,计算各指标遗传与环境方差组分,分析年龄、性别和不同发育期的作用。结果全部双生子分性别校正年龄后,各指标遗传度在0.59～0.87之间;不同发育期各指标遗传度存在差异,肱三头肌皮褶、肩胛下皮褶、2处皮褶厚度之和、体脂百分比的遗传度男生在青春期前期最低,分别为0.55,0.62,0.53,0.51,女生在青春期晚期最低,分别为0.53,0.43,0.24,0.40;男、女瘦体重遗传度随青春期发育进程呈增加趋势。结论遗传因素对儿童青少年皮褶厚度和体成分起主要作用,但年龄、性别和不同发育阶段对其也有一定影响。

Objective To assess the genetic and environmental influences on skinfold thickness and body composition of children and adolescents in different development periods. Methods The triceps and subscapular skinfolds were measured and the body composition were estimated by using Changling＇s and Brozek＇s models in a total of 376 twin pairs of Han nationality,including 245 monozygotic（MZ） and 131 like-sex dizygotic（DZ） twin pairs aged 6 to 18 years. Model-fitting method with Mx package was performed to evaluate the proportion of variance components and to analyze the effect of sex, age and development period on the skinfold thickness and body composition. Results The estimated heritabilifies of each item were from 0. 59 to 0. 87 after adjusting for age. The heritabilities of triceps skinfolds, subscapular skinfolds, sum of triceps and subscapular skin.folds and body fat percent were the lowest in pre-adolescent period in the boys（0. 55,0. 62,0. 53, 0. 51, respectively） and the lowest in late-adolescent period in girls （ 0. 53,0. 43,0. 24,0. 40, respectively）. In the course of adolescence, the heritabilities of lean body mass increased steadily in both boys and girls. Condnsion The skinfold thickness and body composition of the children and adolescents are mainly influenced by genetic factors and the effects of the age, gender and the development periods should be considered too.