RECENT advances in the genetics of cancer have raised the possibility of widespread DNA testing for the detection of predisposition to cancer. This may allow individuals at high risk to avail themselves of preventive measures and potentially avoid early death. At least one company has already announced plans to begin offering testing for genetic cancer risk. While much alleviation of human suffering may eventually result from these advances in cancer genetics, a number of important questions must be addressed before widespread testing of this sort can be recommended.
Two relatively common heritable cancer risk genes have recently been located. Among people with colon cancer, it appears that as many as 10% carry an altered germline copy of a gene called MSH2.1-3 Individuals with an altered MSH2 gene face an approximately 80% risk of colon cancer; women also have an elevated risk of endometrial and ovarian cancer. Intense medical surveillance
Collins FS, Benjamin LJ, Botstein D, Cox JR, Davidson N, Gray JW, Holtzman N, Housman DE, Jamison KR, Rothstein R, Smith DC, Smith LM, Spence MA, Tilghman SM. Statement on Use of DNA Testing for Presymptomatic Identification of Cancer Risk. JAMA. 1994;271(10):785. doi:10.1001/jama.1994.03510340075038