The -675 4G/5G polymorphism in the PAI-1 gene may not contribute to the risk of PCOS.

OBJECTIVE The association between the -675 4G/5G polymorphism in PAI-1 gene and PCOS has been studied with inconclusive results. We sought to investigate this inconsistency by performing a comprehensive meta-analysis on the polymorphism. MATERIALS AND METHODS Searches were performed in the PubMed, Embase, CNKI and Wanfang databases, covering all papers. Statistical analysis was performed using Revman5.2 and STATA11.0 software. A total of 11 case-control studies were extracted on the polymorphism involving 1861 PCOS cases and 1187 controls. RESULTS The results showed that, no significant increased/decreased risk were found for the polymorphism for PCOS: OR = 1.03, 95% CI = 0.77-1.66, p = 0.52 for 4G4G + 4G5G vs. 5G5G; OR = 0.99, 95% CI = 0.66-1.49, p = 0.96 for 4G4G vs. 5G5G + 4G5G; OR = 1.08, 95% CI = 0.66-1.79, p = 0.76 for 4G4G vs. 5G5G; OR = 1.11, 95% CI = 0.78-1.58, p = 0.56 for 4G5G vs. 5G5G; OR = 1.00, 95% CI = 0.71-1.41, p = 0.99 for 4G vs. 5G. In the further subgroup analysis by ethnicity, we did not find a significant association between the polymorphism for PCOS risk in either Asians or Europeans. CONCLUSIONS Our findings demonstrated that -675 4G/5G polymorphism in the PAI-1 gene might not be a risk factor for the development of PCOS.