Direct Sequencing for Juvenile Polyposis Gene SMAD4/DPC4 Mutations

Juvenile polyposis (JP) is a rare dominantly inherited tumor predisposition syndrome, the typical lesion being a benign hamartomatous intestinal polyp with dilated crypts. Solitary juvenile polyps are relatively common in childhood, and appear not to be associated with neoplasia (1 ,2 ). There is no consensus of how many polyps in one patient would justify the diagnosis for the condition. The number of polyps usually present is low compared to familial adenomatous polyposis where typically hundreds of lesions are found in the fully developed disease. Five histologically confirmed juvenile polyps in one patient have been proposed as a sufficient number to establish juvenile polyposis diagnosis (3 ). Juvenile polyposis usually presents in childhood, most often with rectal bleeding. In some cases associated congenital defects such as malform ations of the heart and the cranium occur (4 ,5 ).