In addition, when 25OHD and BMI were assessed together using mvMR method, we found that genetically predicted BMI increased the risk of PCOS (OR = 2.98, 95% CI = 2.12~4.19, P < 0.001), so did fasting insulin (OR = 2.30, 95% CI=1.02~5.15, P = 0.044). The gene discussed is INS; the disease is polycystic ovary syndrome.