Phenotypic effects of apolipoprotein structural variation on lipid profiles. IV. Apolipoprotein polymorphisms in a small group of black women from the Healthy Women Study

Structural variation in apolipoprotein E has been shown to influence lipid and lipoprotein concentrations. The purpose of the present study was to investigate several apolipoproteins in a group of Black women from the Healthy Women Study (HWS). HWS is a community‐based prospective study of 541 premenopausal women who are being followed through the menopause to determine the influence of biological, genetic, and psychosocial phenomenon on cardiovascular risk factors. Of the 541 subjects, 48 are Black. Serum from most of these 48 Black women was used to type seven apolipoproteins (APO A‐I, APO A‐II, APO A‐IV, APO C‐II, APO D, APO E, and APO H). Five of these apolipoproteins are polymorphic in Blacks (APO A‐IV, APO C‐II, APO D, APO E and APO H). Only two and three individuals, respectively, were heterozygous at the APO D and APO C‐II loci. APO A‐IV, E, and H exhibited more variation, however, only APO E phenotypes could be used for statistical analyses. Three common phenotypes, APO E 3–2, APO E 3–3, and APO E 4–3, were used in analysis of variance on four quantitative lipid variables. Despite small numbers, the effect of APO E phenotype was apparent. The APO E 3–2 phenotype showed reduced average levels of total cholesterol, apolipoprotein B (APO B) and low‐density lipoprotein cholesterol (LDL_C), and the APO E 4–3 phenotype showed increased levels (P ≥ .0497). The APO E 3–3 homozygote was intermediate on all three. Because of small numbers in the cells of APO A‐IV and APO H phenotypes, these were not analyzed with respect to quantitative lipids.