Drs. Nicole Beauchemin and Philippe Gros are studying genes pre-disposing to the development of colon cancer in a mouse model to identify genes that could be used as markers identifying individuals or populations at risk of developing colon cancer. The identification and use of new markers for colon cancer in population screening would facilitate the early treatment of these patients and increase patients’ chances of survival in the long term. We have identified the Ccs3 gene interval (20 genes) for susceptibility to colon cancer in 28 unique strains of mice (AcB/BcA) by exposure to a carcinogen. Our first aim is to pinpoint which of the 20 candidate genes is responsible for colon cancer development by detecting possible mutations in these colon cancer genes. We will validate the gene candidate by creating mutant mice bearing different gene alterations and testing whether or not they develop colon tumors. We will then examine human normal colon and tumors to evaluate whether the human gene is mutated in primary clinical specimens of colorectal cancer.