Association of Taq 1B CETP polymorphism with insulin and HOMA levels in the population of the Canary Islands

Abstract

Background and aims Cholesteryl ester transfer protein (CETP) is an enzyme with a key role in lipoprotein metabolism. A common genetic polymorphism, the Taq 1B, influences CETP activity and HDL-cholesterol levels, with individual homozygotes for the B1 allele exhibiting higher enzyme activity and lower HDL-cholesterol levels than carriers of at least one B2 allele. Our aim was to analyze the influence of Taq 1B CETP polymorphism on cardiovascular risk factors in a representative sample of adult subjects from Canary population. Methods and result A total of 518 adult subjects from the Canary Islands, enrolled in a nutritional survey (the ENCA study), were included. The Taq 1B polymorphism was analyzed by PCR–RFLP. Compared with individuals with at least one B2 allele, and after adjusting for age, sex, BMI, waist perimeter, smoking and alcohol intake, carriers of the B1B1 genotype showed lower HDL-cholesterol levels (geometric mean (95% CI): 46.6 (44.5–48.8) vs. 50.6 (49.1–52.9) mg/dl; P = 0.003); and higher insulin (geometric mean (95% CI): 11.1 (10.5–11.9) vs. 10.0 (9.5–10.5 μU/ml; P = 0.008) and HOMA levels (geometric mean (95% CI): 2.3 (2.1–2.5) vs. 2.1 (1.9–2.1); P = 0.009). In addition, the B1B1 genotype was more frequent in individuals who had low levels of HDL-cholesterol according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria (Odds Ratio (OR): 1.563; 95% CI: 1.04–2.34; P = 0.030), and in those included in the upper quartile of insulinemia (OR: 1.90; 95% CI: 1.20–3.03; P = 0.007) and HOMA (OR: 1.61; 95% CI: 1.02–2.57; P = 0.043). Conclusion The observed influence of Taq 1B polymorphism on insulin levels and HOMA highlights the possible role of CETP in the regulation of glucose homeostasis.