Additionally, the MR-Egger intercept test detected overall directional pleiotropy only in the case of endometrial cancer (pintercept = 4 × 10−4) and returned a potential positive association between bilirubin levels, predicted by non-UGT1A1 SNPs, and endometrial cancer (OR 1.37; 95% CI 0.99–1.89) (Figure 1C and Table S2). Here, UGT1A1 is linked to endometrial cancer.