HindIII DNA polymorphism in the lipoprotein lipase gene and plasma lipid phenotypes and carotid artery atherosclerosis

Lipoprotein lipase (LPL) is the rate limiting enzyme in the hydrolysis of core triglyceride in chylomicron and very low density lipoprotein (VLDL) thus affecting a broad spectrum of plasma lipid levels. In this paper, we investigated the association of a HindIII polymorphism in the LPL gene with plasma lipid levels and carotid artery wall thickness measured by B-mode ultrasonography. A total of 238 Caucasian subjects were selected from the Atherosclerosis Risk In Community (ARIC) study (male = 131, female = 107) based on their fasting triglyceride and LDL-cholesterol levels: normolipidemic (n = 48), hypertriglyceridemic (n = 44), hypercholesterolemic (n = 36), and hypertriglyceridemic-hypercholesterolemic (n = 110) groups. We observed a marginally significant association between lipid phenotypes and HindIII genotypes (P = 0.04) in males, with the hypertriglyceridemic and hypercholesterolemic groups having a higher frequency (0.65) of the H+H+ genotype than the other two groups (pooled: 0.55). In males, there was also a significant association between HindIII genotypes and carotid artery wall thickness after considering the effects of age, body mass index, cigarette smoking, lipid phenotype and diabetes status (P = 0.013), with the H+H+ genotype having a higher average value of carotid artery wall thickness (0.84 +/- 0.15 mm) than the other two genotype groups (0.76 +/- 0.14 mm in H+H- genotype class, 0.75 +/- 0.13 mm in H-H- genotype class). In females, no significant associations among LPL HindIII genotype, lipid phenotype and carotid artery wall thickness were observed. These results suggest that the LPL HindIII polymorphism influences LPL-catalyzed, triglyceride-rich lipoprotein metabolism and carotid artery atherosclerosis in a gender-specific manner.