The mouse model of serrated intestinal tumorigenesis, including carcinomas, that we describe here, based on concurrent Cdx2 inactivation and BRAFV600E expression in distal mouse intestinal epithelium, is the first serrated mouse colon cancer model to our knowledge to be based on two signature defects common to a significant subset of human serrated morphology CRCs. The gene discussed is CDX2; the disease is colonic neoplasm.