Population subgroup analysis showed that there was a significant correlation between VDR ApaI rs7975232 (A > C) polymorphism and PCOS susceptibility in the Asian population (allelic model C vs. A: OR = 1.21, 95%CI = 1.04~1.42, P = 0.016; dominant model CC vs. CA + AA: OR = 1.70, 95%CI = 1.26~2.29, P = 0.001) (Fig. 2), but this association was not found in the Caucasian population. The gene discussed is VDR; the disease is polycystic ovary syndrome.