To address the potential means by which RAP might be acting to inhibit polyposis, in a second group of mice (N = 5 per time point), we inactivated Apc in the colon epithelium of CDX2P-CreERT2 Apcfl/fl mice by TAM administration and followed the mice endoscopically until they had dense large polyps. The gene discussed is APC; the disease is polyposis.