A meta-analysis was undertaken to assess the impact of apolipoprotein E (apo E) alleles (epsilon 2, epsilon 3, and epsilon 4) on coronary disease in 14 published observational studies (9 clinical coronary disease and 5 coronary angiography). In comparison with epsilon 3, the epsilon 4 allele was associated with greater odds for coronary heart disease, and summary estimates of the odds ratios (ORs) and (95% confidence intervals) for both sexes combined were OR = 0.98 (0.85-1.14) for epsilon 2 and OR = 1.26 (1.13-1.41) for epsilon 4. Separate analyses for men and women showed similar associations. In angiographic studies the relative odds for significant coronary artery disease among both sexes combined was OR = 0.76 (0.55-1.05) for epsilon 2 and OR = 1.11 (0.88-1.40) for epsilon 4. The overall impression is that epsilon 4 is associated with clinical and coronary disease and that results are similar in men and women.