The study was an independent research project ancillary to the NGHS and utilized the extensive biological and environmental information available from the NGHS core data base. Blood samples were obtained from 1,133 girls seen at their followup examinations in Year 7 in order to determine genotypes at those loci known to be implicated in lipid metabolism and obesity. Both protein [apolipoproteins C-II, D, and E and LP(a)] and DNA [apolipoprotein B, lipoprotein lipase (LPL), and LDL receptor] were analyzed. The distribution of genetic variation within each ethnic group was determined. At each candidate gene locus, the genotype effects were estimated on quantitative level of apolipoproteins and lipoproteins, and also on the degree and distribution of body fat after adjusting for concomitant variables (such as age, biologic maturation stage adiposity) within each ethnic group. By comparing the frequencies of genotypes at candidate loci, their allelic effects were assessed as well as their impact on blood lipids and obesity development in Black and white females.