Background: The apolipoprotein E alleles epsilon2 and epsilon4 have been reported as independent risk factors for coronary artery disease (CAD) and as predictors for the development of atherosclerosis.
Methods and results: We determined by polymerase chain reaction the distribution of apolipoprotein E polymorphism in 320 Saudi blood donors (BD), 96 CAD patients, and 40 control subjects who had undergone angiography. Compared to controls, only epsilon4 was elevated in CAD patients. More than 61% (P <.0001) of the patients had angina, and 52.1% (P <.05) were diabetic; both of these factors were strongly associated with the presence of allele epsilon2. The epsilon2 allele was also associated with hypertension, elevated serum triglycerides, and total cholesterol. On the other hand, the allele epsilon4 appeared to be associated with increased risk of CAD and was also associated with hypertension, 3-vessel disease, and restenosis.
Conclusions: Accordingly, epsilon4 may be associated with increased risk of CAD, whereas epsilon2 appears to be a predictor of several risk factors for atherosclerosis.