Lipoprotein lipase gene polymorphism and lipid profile in patients with hypertriglyceridemia

To assess lipid profile and the genotype distribution of lipoprotein lipase gene polymorphism at Pvu II polymorphic site within the intron between exons 6 and 7 in patients with hypertriglyceridemia.

Pvu II polymorphism was determined in 116 hypertriglyceridemic patients and 50 normolipidemic controls from Zagreb, Croatia. DNA was extracted from peripheral blood mononuclear cells. Polymerase chain reaction was used for amplification of 6th intron, which was then restricted with Pvu II-restriction endonuclease. Serum lipid and lipoprotein fractions were determined by standard enzymatic methods. Cholesterol concentrations in HDL subfractions, HDL2 and HDL3, were determined after precipitation with polyethyleneglycol. Apolipoproteins (apo) A-I and B were determined by immunonephelometry.

Triglycerides showed a positive correlation with total cholesterol (r=0.222, 95% CI=0.041-0.389, p=0.017) and inverse correlation with HDL-cholesterol (r= -0.278, 95% CI= -0.449 to -0.088, p=0.005), especially with HDL3-cholesterol (r= -0.333, 95% CI= -0.497 to -0.147, p=0.001). The respective frequencies for genotypes /, +/, and +/+ were 22, 58, and 36 in the patient group, and 17, 17, and 16 in the control group. Serum triglycerides in the patient group, expressed as median in mmol/L, were 3.30 (range, 2.60-10.90), 3.60 (range, 2.50-21.50), and 3.99 (range, 2.50-15.56), respectively. Serum concentration of triglycerides differed significantly between the +/+ and / genotype (p=0.043).

There is an association between genetic variation at the locus for lipoprotein lipase and high serum triglyceride levels. This might prove useful in the detection of individuals susceptible to the development of hypertriglyceridemia, as well as a marker in the analysis of this genetic defect in patient families.