OBJECTIVETo examine the association of the Thr394Thr polymorphism of PPARGC1A gene with type 2 diabetes (T2DM), insulin resistance (IR) and other metabolic disorders in a Chinese population.

METHODSThree hundred and seven subjects including 151 T2DM patients and 156 normal glucose tolerant controls (NC) were enrolled in this study. The Thr394Thr G/A polymorphism was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Glucose, insulin, lipids levels were determined in all subjects. Body mass index (BMI), waist circumferences, index of homeostasis model assessment-insulin resistance (HOMA-IR) and blood pressure were also measured.

RESULTSThe diabetic subjects had higher levels of BMI, waist circumferences, blood systolic pressure, triglycerides and lower levels of high density lipoprotein-cholesterol (HDL-C) compared with those of control subjects (P<0.05). About 43.7% (66/151) of the T2DM subjects had the AG genotype, while 37.2% (58/156) in the NC group. The frequency of the A allele was 0.225 in T2DM, and 0.186 in the NC subjects. There were no significant differences either in genotype or allelic distribution of G/A polymorphism between the two groups. In the T2DM group, subjects with AA and GA genotypes had significantly higher levels of HOMA-IR, waist circumferences and lower levels of HDL-C (P<0.05) than those carrying GG genotype. HOMA-IR in subjects with AA and AG were significantly higher than those with GG genotype in both groups.

CONCLUSIONThe A allele of the Thr394Thr (G-->A) polymorphism of the PPARGC1A gene was associated with insulin resistance, and may be related to central obesity and decreased HDL-C levels in Chinese population. The relationship between this polymorphism and T2DM needs further investigation.