The relationship between apolipoprotein E (Apo E) phenotypes and progression of coronary atherosclerosis was investigated in 125 patients with coronary artery disease (CAD) proven angiographically (101 males, 24 females).
A mutant form of apolipoprotein E that is defective in binding to low density lipoprotein receptors is associated with familial type III hyperlipoproteinemia, a genetic disorder characterized by elevated plasma cholesterol levels and accelerated coronary artery disease.
Evidently, apolipoprotein E polymorphism can contribute to total and LDL-cholesterol concentrations in serum, thereby affecting risk of coronary heart disease and myocardial infarction.
This aspect of the methodology is illustrated using two population data sets, the first relating APO-E genotype to the frequency of individuals undergoing maintenance hemodialysis and the second relating APO-B genotype to the frequency of coronary artery disease.
Genetic effect of apolipoprotein(a) and apolipoprotein E polymorphisms on plasma quantitative risk factors for coronary heart disease in American black women.
However, context-dependent influences of apolipoprotein E polymorphism on the risk for coronary heart disease have been reported; that is, depending on ethnic origin, gender and lifestyle, apolipoprotein E4 confers a major risk factor for coronary heart disease.
The XbaI, EcoRI and the signal peptide insertion/deletion (I/D) polymorphic sites of APOB gene, the CfoI polymorphic site of apolipoprotein E gene (APOE), and the insertion/deletion polymorphism of angiotensin I-converting enzyme (ACE) gene were studied using polymerase chain reaction (PCR) in 55 postmenopausal women with coronary artery disease (CAD) and in 119 control women of equivalent age.
One such potential polymorphism is in the apolipoprotein E (apoE) gene, which is involved in cholesterol metabolism, where the epsilon4 allele is associated with an increased risk of coronary artery disease and is under represented in elderly populations.