UNIVARIATE AND MULTIVARIATE GENETIC-ANALYSIS OF SUBCUTANEOUS FATNESS AND FAT DISTRIBUTION IN EARLY ADOLESCENCE

Univariate and multivariate analyses of the genetic and environmental contributions to variance in adipose tissue and adipose tissue distrib ution were carried out in early adolescents. Stature, weight, body mas s index (BMI), and five subcutaneous skinfolds were measured at half-y early intervals in 105 MZ and DZ twin pairs from 10 to 14 years. The m ost parsimonious model, which provided an adequate explanation for var iation in the BMI, five skinfolds, and the T/E ratio, included additiv e genetic and specific environmental factors. Multivariate analyses of the genetic architecture of subcutaneous fat indicated a general skin fold genetic factor, an extremity skinfold genetic factor, and skinfol d specific genetic factors. This implies that all skinfolds are under control of the same set of genes, that a different set of genes partly controls extremity skinfolds, and that other genes have a small skinf old specific impact. Environmental contributions included a general sk infold environmental factor and skinfold specific environmental factor s. BMI is under control of the same set of genes as skinfolds and show s high genetic correlations with trunk skinfolds, which implies that n early the same genes may influence trunk skinfolds and the BMI. All mo dels were fairly consistent across the age range.