Background: Cholesteryl ester transfer protein (CETP) mediates the transfer of cholesteryl ester from HDL in exchange for triglycerides in apolipoprotein B-containing lipoproteins.
Methods and results: We studied 2 common mutations in CETP, A373P and R451Q, in 8467 healthy women and men from the Danish general population and in 1636 Danish women and men with ischemic heart disease. The prevalence of 373P and 451Q was 0.10 and 0.07, respectively, for heterozygous carriers and 0.003 and 0.002, respectively, for homozygous carriers. All carriers of the 451Q allele also carried the 373P allele. HDL cholesterol in female noncarriers, heterozygotes, and homozygotes of 373P was 1.74+/-0.01 (mean+/-SE), 1.62+/-0.02, and 1.38+/-0.09 mmol/L, respectively (ANOVA, P:<0.001). In men, equivalent values were 1.40+/-0.01, 1.26+/-0.02, and 1.19+/-0.09 mmol/L, respectively (ANOVA, P:<0.001). HDL cholesterol decreased similarly as a function of 451Q genotypes and all 373P/451Q genotype combinations. Furthermore, apolipoprotein AI and the HDL cholesterol/apolipoprotein AI ratio was also lower in carriers of either of these mutations for both sexes. Finally, the CETP genotype was not associated with risk of ischemic heart disease unless we adjusted for HDL cholesterol: female heterozygous and homozygous carriers versus noncarriers had 36% lower risk of ischemic heart disease (95% CI 4% to 57%); in male carriers, we observed a similar trend.
Conclusions: The A373P/R451Q polymorphism in CETP is associated with decreases in HDL cholesterol of 0.12 to 0.36 mmol/L in women and 0.14 to 0.21 mmol/L in men and possibly with a paradoxical 36% decrease in the risk of ischemic heart disease in women.