Background: Genome-wide association studies in European Americans have reported several single-nucleotide polymorphisms (SNPs) in the lipoprotein lipase gene associated with plasma levels of high-density lipoprotein cholesterol (HDL-C) and triglycerides. However, the influences of the lipoprotein lipase SNPs on longitudinal changes of these lipids have not been systematically examined.
Methods and results: On the basis of data from 2045 African Americans and 2116 European Americans in the Coronary Artery Risk Development in Young Adults study, we investigated cross-sectional and longitudinal associations of lipids with 8 lipoprotein lipase SNPs, including the 2 that have been reported in genome-wide association studies. Plasma levels of HDL-C and triglycerides were measured at 7 examinations during 20 years of follow-up. In European Americans, rs328 (Ser447Stop), rs326, and rs13702 were significantly associated with cross-sectional interindividual variations in triglycerides and HDL-C (P<0.005) and with their longitudinal changes over time (P<0.05). The minor alleles in rs326, rs328, and rs13702 that predispose an individual to lower triglycerides and higher HDL-C levels at young adulthood further slow down the trajectory increase in triglycerides and decrease in HDL-C during 20 years of follow-up. In African Americans, these 3 SNPs were significantly associated with triglycerides, but only rs326 and rs13702 were associated with HDL-C (P<0.008). Rs328 showed a stronger association in European Americans than in African Americans, and adjustment for it did not remove all of the associations for the other SNPs. Longitudinal changes in either trait did not differ significantly by SNP genotypes in African Americans.
Conclusions: Our data suggest that aging interacts with LPL gene variants to influence the longitudinal lipid variations, and there is population-related heterogeneity in the longitudinal associations.