We applied logistic regression analysis and identified 6 CpG sites that are unique to HCC and can be used to diagnose HCC: cg26581504 (BCO2), cg05106294 (DKK3), cg20342184 (GRHL2), cg23623667 (KCNQ1), cg14250130 (PFKP), and cg13564825 (PPP1R14A). The gene discussed is KCNQ1; the disease is hepatocellular carcinoma.