RT Book, Section A1 Aaltonen, Lauri A. A2 Valle, David L. A2 Antonarakis, Stylianos A2 Ballabio, Andrea A2 Beaudet, Arthur L. A2 Mitchell, Grant A. SR Print(0) ID 1181414612 T1 Peutz-Jeghers Syndrome T2 The Online Metabolic and Molecular Bases of Inherited Disease YR 2019 FD 2019 PB McGraw-Hill Education PP New York, NY SN 9780071459969 LK ommbid.mhmedical.com/content.aspx?aid=1181414612 RD 2024/03/28 AB The typical features of Peutz-Jeghers syndrome (PJS) are mucocutaneous melanin pigmentation and gastrointestinal polyposis.Peutz-Jeghers polyps are hamartomas characterized by a stromal tree-like pattern of smooth muscle tissue.PJS patients are predisposed to cancer. An excess of gastrointestinal as well as extraintestinal cancers has been reported in PJS families. The cancer predisposition is less focused than in many other cancer-susceptibility syndromes.The major predisposing gene is LKB1. LKB1 mutations are found in most but not all PJS patients. At present it is unclear whether more predisposing loci exist.LKB1 is a serine/threonine kinase, and it has been proposed to function as an upstream regulator of AMP-activated protein kinase. The germ-line mutations associated with tumorigenesis are usually of an inactivating nature, suggesting a role as a tumor suppressor.