MOLECULAR-GENETICS AND HEREDITARY CANCER - HEREDITARY NONPOLYPOSIS COLORECTAL-CARCINOMA AS A MODEL

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is frequently ass ociated with the germline mutation of a DNA mismatch repair gene. Tumo rs from these patients typically exhibit microsatellite instability, w hich is a reflection of their lack of mismatch repair activity. The ge netic diagnosis of these individuals relies on family history, tumor a nalysis for evidence of lack of mismatch repair, and, finally, mutatio nal analysis of the mismatch repair genes themselves. Early diagnosis of germline mutations in HNPCC individuals is likely to lead to improv ed cancer surveillance and early tumor detection. (C) 1997 American Ca ncer Society.