The NHLBI Family Heart Study is a multicenter, population-based study
of genetic and nongenetic determinants of coronary heart disease (CHD)
, atherosclerosis, and cardiovascular risk factors. In phase I, 2,000
randomly selected participants and 2,000 with family histories of CHD
were identified among 14,592 middle-aged participants in epidemiologic
studies. Medical histories from these individuals, their parents, and
their siblings were used to calculate family risk scores that compare
d the number of reported and validated CHD events with the number expe
cted based on the size, sex, and age of family members. A total of 657
families with the highest risk scores and early-onset CHD and 588 ran
domly sampled families had clinic examinations that included electroca
rdiograms, carotid artery ultrasound scans, spirometry, measurements o
f body size, blood pressure, lipids, lipoproteins, hemostatic factors,
insulin, glucose, and routine chemistries. Additional biochemical and
genetic studies are being performed on selected participants. Serum,
plasma, lymphocytes, red cells, and DNA are stored for future studies,
including genotyping of candidate genes and anonymous markers. Contri
butions of genes, shared and individual environments, and behaviors to
variations in risk factors, preclinical atherosclerosis, and CHD will
be estimated. Linkage studies, including the quantitative trait loci
approach, are planned.