Medical records and death certificates were reviewed to evaluate coronary artery disease endpoints in all adults members of the pedigrees. Clinical data collected included: a history of symptoms of coronary artery disease, arteriosclerosis obliterans, cerebrovascular disease or surgery for these diseases; smoking; medication; history of genetic relationships. Measurements were made of cholesterol, triglycerides, HDL and LDL cholesterol, apo A-I, apo A-II, apo E, apo C-III, apo C-II, apo B, apo Lp(a), LDL apo B, HDL apo E, and DNA extraction. Lipid, lipoprotein, and apolipoprotein phenotypes and the restriction fragment length polymorphisms (RFLP) were measured in candidate genes for coronary artery disease. Genetic and phenotype analyses were conducted at the University of Michigan. The RFLP and apolipoprotein isotyping analyses were conducted at the University of Pittsburgh. RFLP analysis and LDL receptor and A-I gene analysis were conducted at Charing Cross Medical Center in London, England.