The investigation of individuals with inflammatory bowel disease provided evidence that the repeated inflammatory cycles affecting the colonic epithelium induce a 2.4-fold increase of the average rate of colonic crypts affected; the mutations observed in IBD non-neoplastic epithelium mostly involve ARID1A, FBXW7, PIGR, and ZC3H12A genes in the IL17 and Toll-like receptor pathways [77]. Here, IL17A is linked to inflammatory bowel disease.