Genetic variation of GPLD1 associates with serum GPI-PLD levels: a preliminary study.

HDL is a heterogeneous mixture of lipoprotein particles varying in composition, size, and function. We and others have described a small (7.0nm), minor (0.1% of total apolipoprotein AI) particle containing apolipoprotein AI, AIV and glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) in humans the function of which is not entirely known. Circulating GPI-PLD levels are regulated by multiple factors including genetics. To determine if genetic variation in GPLD1 affects circulating GPI-PLD levels, we examined the relationship between 32 SNPS upstream, within, and downstream of GPLD1 and circulating GPI-PLD levels in Caucasians (n=77) and African-Americans (n=99). The genotype distribution among races differed at 13 SNPs. Nine SNPS were associated with circulating GPI-PLD levels in Caucasians but not African-Americans. These results suggest that genetic variation of GPLD1 appears to associate with circulating GPI-PLD levels. This article is part of a Special Issue entitled Advances in High Density Lipoprotein Formation and Metabolism: A Tribute to John F. Oram (1945-2010).