Among the 7 controls from the KCCMR colony, we found no individuals with predicted damaging mutations in MSH2, MSH6 or PMS2. We did find one of the controls was heterozygous for both the stop codon gained and the 2-bp deletion in the promotor of MLH1. This animal was found to be free of CRC at necropsy but was diagnosed with ocular carcinosarcoma. This evidence concerns the gene MSH2 and colorectal carcinoma.