MSH2 and colorectal carcinoma: Compared with published estimates of CRC incidence in former generations before colonoscopy was widely instituted, CRC incidence in LS patients subjected to regular colonoscopy surveillance was increased for path_MLH1 and path_MSH2 carriers, not reduced for path_MSH6 carriers and possibly (but not significantly) reduced in path_PMS2 carriers < 50 years of age [20].