Lynch Syndrome 4, also known as hnpcc4, is related to familial adenomatous polyposis 1 and rectum signet ring adenocarcinoma. An important gene associated with Lynch Syndrome 4 is PMS2 (PMS1 Homolog 2, Mismatch Repair System Component), and among its related pathways/superpathways are BRCA1 Pathway and Prader-Willi and Angelman syndrome. Affiliated tissues include colon and small intestine, and related phenotypes are endometrial carcinoma and ovarian neoplasm