NONPENETRANCE AND LATE APPEARANCE OF POLYPS IN FAMILIES WITH FAMILIALADENOMATOUS POLYPOSIS

One case of non-penetrance of the familial adenomatous polyposis (FAP) gene at 59 years of age and late onset of polyps on endoscopy and bio psy in this and two other families is described. Screening protocols s hould include dental screening as well as indirect ophthalmoscopy and endoscopy to detect minimal manifestations of the gene. In the absence of a specific DNA predictive test, bowel screening should continue we ll beyond 30 years of age.