Association between insulin resistance and cholesteryl ester transfer protein gene polymorphism in type 2 diabetes mellitus

Objective: To study the association between cholesteryl ester transfer protein (CETP) gene polymorphism and insulin resistance in type 2 diabetes.

Methods: CETP-TaqIB gene was genotyped with polymerase chain reaction-restriction enzyme fragment polymorphism analysis in 108 patients with type 2 diabetes and in 60 normal controls. Plasma lipids, fasting insulin, insulin sensitivity index and insulin resistance index were determined in 108 patients with type 2 diabetes.

Results: The distribution of CETP-TaqIB genotypes and B1B2 allele frequency in the patients with type 2 diabetes were similar to that in general population. High density lipoprotein cholesterol (HDL-C), apolipoprotein A1(apoA1) and insulin sensitivity index (ISI) levels were significantly higher in B2B2 genotype than in B1B1 genotype. Fasting insulin (FINS) and Homeostasis model assessment-insulin resistance (HOMA-IR) levels were significantly lower in B2B2 genotype than in B1B1 genotype. No significant differences in triglyceride (TG), total cholesterol(TC),low density lipoprotein cholesterol (LDL-C), apolipoprotein B (apoB) levels were observed among different CETP-TaqIB genotype groups. By multivariate analysis, the determinants of ISI and HOMA-IR were body mass index (BMI), TC, HDL-C and CETP-TaqIB genotype.

Conclusions: The CETP-TaqIB genotype is independently associated with insulin resistance and lipid metabolism. It may be an important risk factor of insulin resistance in type 2 diabetes.