Subgroup analysis based on the ethnic population showed that the CDH1 promoter methylation status was significant associated with the risk of ovarian cancer in Asian population and Caucasian population (OR = 13.20, 95 % CI = 6.12 - 28.45, P < 0.001; OR = 3.84, 95 % CI = 1.52 - 9.74, P = 0.005; respectively) (Fig. 3). Here, CDH1 is linked to ovarian cancer.