Association between Polymorphism of Insulin Gene Variable Number Tandem Repeats and Polycystic Ovary Syndrome: A Meta-Analysis

Objective The present meta-analysis aimed to investigate the association between the polymorphism of insulin gene variable number tandem repeats and polycystic ovary syndrome. Methods We collected all the case-control studies on the association between polymorphism of insulin gene variable number tandem repeats and polycystic ovary syndrome. Meta-analysis was performed using RevMan5.2 software. Results 10 studies were recruited. In overall groups, individuals who carried Ⅰ allele were associated with the 18% decreased risk of PCOS OR(95% CI)= 0.82(0.72,0.94), P=0.004. Compared with those of Ⅰ/Ⅲ+Ⅲ/Ⅲ genotypes, subjects with Ⅰ/Ⅰ genotype had less susceptibility to PCOS OR(95%CI)= 0.78(0.65,0.94),P=0.010. Stratified analyses showed that the risk of PCOS in the Caucasian population carrying Ⅰallele was reduced by 16%, compared with the carriers with ⅢalleleOR(95%CI)=0.84(0.73,0.98), P=0.023. While in Recessive model and Homozygote model, Asian subgroup had the dominant protective effect OR(95%CI)=0.79(0.63,0.97),P=0.028 and OR(95%CI)=0.21(0.05,0.95),P=0.042 respectively. Conclusion Polymorphism of insulin gene variable number tandem repeats was associated with the decreased risk of PCOS, but the associations were various in the different ethnical groups.