The peroxisome proliferator-activated receptor-gamma2 (PPAR(gamma2)) represents the transcriptional master regulator of adipocyte differentiation and therefore has been suggested as candidate gene for the pathogenesis of obesity, type 2 diabetes and related metabolic disorders. Aim of our study was to determine the frequency of a missense point mutation within exon 2 of PPAR(gamma2), Pro12Ala, and its possible association with metabolic parameters as well as diabetic retinopathy (in a population-based sample of 560 (318 male ad 242 female) type 2 diabetic patients. Subsequent to genomic PCR amplification, the Hpa-II RFLP analysis was used for genotyping.
Results: 436 (77.9%) subjects were homozygous for the wildtype allele (Pro/Pro), 118 (21.1%) were heterozygous (Pro/Ala) and 6 (1.1%) were homozygous for the mutated allele (Ala/Ala). Genotype frequency was calculated to be 0.81 for the wildtype and 0.19 for the mutated allele. These frequencies did not differ from non-diabetic cohorts examined earlier. In contrast to females, total cholesterol and LDL-cholesterol were significantly higher in males (Total cholesterol: 281.8 +/- 51.3 vs 253.1 +/- 49.8 mg/dl, p < 0.0001; LDL-cholesterol: 182.0 +/- 49.2 vs 155.6 +/- 42.0 mg/d, p < 0.0001) in the presence of the mutated allele as compared to the wildtype subgroup. No differences were found with respect to BMI, HbA1c, blood pressure and serum levels of leptin nor to prevalence of retinopathy. Pro12Ala polymorphism of PPAR(gamma2) gene is not associated with diabetic retinopathy but is associated with dyslipidemia in male type 2 diabetic patients.