It is mainly referred to mutations in the MLH1, MSH2, MSH6, EPCAM, and PMS2 genes, which predispose individuals to hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome, which significantly increase the risk of ovarian cancer [37,38,39]. The gene discussed is PMS2; the disease is hereditary nonpolyposis colon cancer.