In epithelial ovarian cancer, the frequently methylated genes were reported to be the cyclin-dependent kinase inhibitor 2B (CDKN2B); estrogen receptor 1 (ESR1); secreted frizzled-related protein 5 (sFRP5); cadherin 13 (CDH13, H-cadherin); Ras association (RalGDS/AF-6) domain family member 1 (RASSF1); mutL homolog 1, colon cancer, nonpolyposis type 2 (MLH1); opioid binding protein/cell adhesion molecule-like (OPCML); sulfatase 1 (Hsulf-1); GATA binding protein 4 (GATA4) and death-associated protein kinase 1 (DAPK1) genes (59,60). The gene discussed is ESR1; the disease is ovarian carcinoma.