The colon becomes the site of tumor induction when juvenile APCMin/+ mice (carrying a mutation in the Apc gene to develop multiple intestinal adenomas) or even APC+/+ mice (wild-type at the Apc locus) are intraperitoneally treated with ENU, although the ENU does not induce colonic tumors when adult mice, generally used in toxicity studies, are orally treated [34, 35, 51]. The gene discussed is APC; the disease is neoplasm.