OBJECTIVETo evaluate the relationship between peroxisome proliferator-activated receptor-γ2 (PPARγ2) Pro12Ala polymorphism and type 2 diabetes mellitus (T2DM) in Chinese Han population.

METHODSPubMed, Chinese Biomedicine Database (CBM), China National Knowledge Infrastructure (CNKI) and Wanfang database were searched for all relevant articles investigating the association between PPARγ2 Pro12Ala polymorphism and T2DM that were available from January, 1990 to June, 2011. A total of 29 relevant articles were selected. A Meta-analysis was performed to estimate heterogeneity and the pooled odds ratio (OR) to evaluate the relationship between PPARγ2 Pro12Ala polymorphism and T2DM. The sensitivity analysis was also assessed.

RESULTSA total of 21 qualified articles including 3870 patients with T2DM and 3333 healthy controls were analyzed in the study. The frequencies of the allele Ala12 in T2DM and control groups were 4.13% (320/7740) and 4.56% (304/6666), respectively. There were not heterogeneity (χ(2) = 25.96, P = 0.17) among the 21 qualified articles. The pooled OR (95%CI) value of the frequencies of the PPARγ2 genotype (PA + AA)/PP calculated by fixed effects model was 0.96 (0.81 - 1.14) (P = 0.64). There was not heterogeneity among the remaining articles after excluding the article with the largest weight and the article with larger frequencies of the allele Ala12 respectively (χ(2) values were 24.23, 16.87 respectively, both P values > 0.05). The pooled OR (95%CI) value of the frequencies of the PPARγ2 genotype (PA + AA)/PP of the remaining articles were 1.01 (0.84 - 1.21) and 1.07 (0.89 - 1.28) after excluding the article with the largest weight and the article with larger frequencies of the allele Ala12 (both P values > 0.05).

CONCLUSIONPPARγ2 Pro12Ala polymorphism was not associated with type 2 diabetes mellitus in Chinese Han population.