Furthermore, we demonstrated that the individuals carrying both GPx1 198L (PL+LL genotype) and SOD2 16A (AV+AA genotype) alleles had further increased risk of PCOS compared with the subjects carrying the PP/VV genotype after adjusting age and BMI, implying that the combination of the SOD2 16A and GPX1 198L alleles may have a synergistic effect on the risk of PCOS and patients with PCOS have a genetic susceptibility to oxidative stress. Here, SOD2 is linked to polycystic ovary syndrome.