Genetics of gastrointestinal polyposis.

This review deals with the types of gastrointestinal polyposis in which genetic factors play an essential part, namely, the hamartomatous lesions of Peutz-Jeghers syndrome and multiple juvenile polyposis and the neoplastic tumors of familial polyposis coli and multiple adenomas. The mode of inheritance, associated lesions, malignancy potential, and possible interrelationships between the various types of polyposis are discussed. The knowledge that the lesions are inherited should enable other family members to be investigated and treated at an early stage, a matter of considerable importance in the prevention of cancer when there is an associated risk of gastrointestinal carcinoma.