Insulin receptor substrate-1 (IRS-1) rs1801278G>A polymorphism is associated with polycystic ovary syndrome susceptibility: a meta-analysis

The correlation between insulin receptor substrate-1 (IRS-1) rs1801278G>A polymorphism and polycystic ovary syndrome (PCOS) has been widely studied. However, the results of these studies are conflicting. The current study provides an assessment of the association between the genetic susceptibilities of IRS-1 rs1801278G>A polymorphism and PCOS. A comprehensive meta-analysis was carried out in over 4,555 subjects included in twenty publications which were published up to June 26, 2015. Our findings suggested that the IRS-1 rs1801278G>A genotype was correlated with the susceptibility of PCOS in the allele comparison, heterozygote comparison and the dominant genetic model. In the dominant genetic model, variant A allele carriers (AA+GA) of IRS-1 rs1801278G>A polymorphism increased the susceptibility of PCOS comparing to the homozygote GG [odds ratio (OR)=1.82, 95% confidence interval (CI) 1.30-2.53 for AA+GA vs. GG]. The analysis by different ethnicity groups highlighted that Caucasian population (OR=1.96, 95% CI 1.26-3.04 for AA+GA vs. GG) had significant increased PCOS susceptibility. Bias diagnosis indicated there are slight publication biases in some genetic models, suggesting that these findings should be interpreted with very caution. In summary, our findings suggested that IRS-1 rs1801278G>A polymorphism may be a risk factor for PCOS.