However, certain pathogenic APC variants are associated with the density of colorectal adenomas and the occurrence of extracolonic manifestations (e.g., fundic gland polyposis, duodenal adenomas, osteomas, desmoid tumors, and the CHRPE phenotype) in patients with FAP [15, 25, 26, 128]. The gene discussed is APC; the disease is Familial adenomatous polyposis.