In Project 2, a genome-wide search is carried out to localize genes that contribute to quantitative variation in traits related to atherosclerosis, NIDDM, and obesity. The first, primary task is the genotyping of some 1,400 pedigree members for 391 short tandem repeat (STR) markers using semi-automated, fluorescence based genotyping on an ABI automatic sequencer. When statistical evidence of linkage has been evaluated in Projects 1 and 3 and confirmed, "additional STRs" will be typed in the region to further localize the gene. The initial map will have a 10 centimorgan resolution. Multipoint linkage analysis and gametic disequilibrium analysis will be used to further localize the region containing the gene of interest. The human gene map will then be consulted to identify candidate genes in the region, and these genes will be subjected to a more detailed molecular analysis to identify structural or functional differences that underlie the observed allelic effects.