Lipoprotein subclass and particle size differences in Afro-Caribbeans, African Americans, and white Americans: associations with hepatic lipase gene variation
文摘
Despite a higher prevalence of coronary heart disease risk factors, men of African origin have less coronary atherosclerosis, as measured by coronary calcification, than whites. In part, this is thought to be because of the less atherogenic lipoprotein profile observed in men of African origin, characterized by lower triglycerides and higher high-density lipoprotein (HDL) cholesterol. We hypothesized that the −514C>T polymorphism in the hepatic lipase gene (LIPC) plays a significant role in determining a less atherogenic lipoprotein profile observed in men of African origin. Previously conducted studies of the LIPC −514C>T polymorphism in African Americans may have been confounded by a higher level of European admixture; in addition, the results from these studies do not necessarily apply to other African populations because gene-environment interactions may differ. Thus, we compared nuclear magnetic resonance spectroscopy–measured lipoprotein subclass patterns and LIPC −514C>T genotypes in population-based samples of older white American (n = 532) and African American (n = 97) men from the Cardiovascular Health Study to those among older, less admixed, Afro-Caribbean men (n = 205) from the Tobago Health Study. Men of African origin had a more favorable lipoprotein profile than whites. In addition, levels of low-density lipoprotein cholesterol, total cholesterol, and triglyceride, and large and small very low-density lipoprotein, small low-density lipoprotein, as well as very low-density lipoprotein particle size, were remarkably lower in Afro-Caribbean men than in either African American or white men. The frequency of the LIPC −514T allele was much higher in Afro-Caribbeans (0.57) and in African Americans (0.49) than in whites (0.20). The −514T allele in both populations of African origin, but not in whites, was associated with elevated large HDL and greater HDL size. Our findings indicate that the higher frequency of the LIPC −514T allele found in men of African origin living in different environments significantly contributes to the more favorable distribution of HDL subclasses compared with whites.