APC loss-of-function mutations are associated with over-activation of WNT/β-catenin signalling and subsequent FAP (MIM 175100) or Gardner syndrome [26], characterized by adenomatous polyposis of the colon, multiple supernumerary teeth, craniofacial osteomas, epidermal cysts, congenital hypertrophy of the retinal pigmented epithelium, and desmoid tumours [26,36]. This evidence concerns the gene APC and Familial adenomatous polyposis.