To determine if methylation within the 5' regulatory region of the HLA-G gene differs among OSE and benign and malignant ovarian tumors, we performed sodium bisulfite genomic sequencing of DNA isolated from laser capture microdissected (LCM) tumor cells from 9 adenomas and 9 adenocarcinomas and OSE brushings from the normal ovaries of 4 patients undergoing hysterectomies for reasons unrelated to ovarian cancer. Here, HLA-G is linked to ovarian cancer.