<prompt> All are true about Familial adenomatous polyposis exceptMore than 100 colorectal adenomasMultiple extraintestinal manifestationsLifetime risk of colorectal cancer is 70-80Mutations in the adenomatous polyposis coli APC gene  <response>: Familial adenomatous polyposis FAP is defined clinically by the presence of more than 100 colorectal adenomas but is also characterised by duodenal adenomas and multiple extraintestinal manifestationsmutations in the adenomatous polyposis coli APC gene on the sho arm of chromosome 5. FAP is inherited as an autosomal dominant condition The lifetime risk of colorectal cancer is 100 in patients with FAP. Extracolonic manifestations of FAPEndodermal derivativesAdenomas and carcinomas of the duodenum, stomach,small intestine, thyroid, and biliary treeFundic gland polypsHepatoblastomaEctodermal derivativesEpidermoid cysts Gardner syndromePilomatrixomaCongenital hyperophy of the retinal pigment epithelium CHRPEBrain tumours Turcot syndromeMesodermal derivativesDesmoid tumoursOsteomasDental problemsRef: Bailey and Love, 27e, page: 1259 