Predictive testing for familial adenomatous polyposis in a rural South Indian community

During the course of genome studies in a rural community in the South India n state of Karnataka, DNA-based investigations and counselling for familial adenomatous polyposis (FAP) were requested via the community physician. Th e proposita died in 1940 and FAP had been clinically diagnosed in 2 of her 5 children, both deceased. DNA samples from 2 affected individuals in the t hird generation were screened for mutations in the APC gene, and a frame-sh ift mutation was identified in exon 15 with a common deletion at codon 1061 . Predictive testing for the mutation was then organized on a voluntary bas is. There were 11 positive tests, including confirmatory positives on 2 per sons diagnosed by colonoscopy, and to date surgery has been successfully un dertaken on 3 previously undiagnosed adults. The ongoing success of the stu dy indicates that, with appropriate access to the facilities offered by col laborating centres, predictive testing is feasible for diseases such as FAP and could be of significant benefit to communities in economically less de veloped countries.