Attention is focused on the molecular, genetic and pathophysiological basis of the inherited dyslipoproteinemias associated with premature coronary artery disease with particular reference to familial combined hyperlipidemia, familial moderate hypercholesterolemia, familial elevation of Lp(a) and the carrier state for homocysteinemia. Coordinated studies of characterization of the pathophysiological state, the identification of possible molecular biological defects and the evaluation of these results in families by statistical genetic techniques are performed in each disorder. The role of protein mediated intravascular modification of lipoproteins and the role of oxidation of lipoproteins in each disorder will lead to characterization of these genetic lipoprotein abnormalities. The study is a subproject within a program project grant.