Lately, in addition to rare germline mutations associated with familiar CD (i.e., multiple endocrine neoplasia type 1 (MEN1) and aryl hydrocarbon receptor interacting protein (AIP) mutations), somatic mutations in novel CD predisposing genes—e.g., ubiquitin specific peptidase 8 (USP8) and 48 (USP48) and BRAF—have been discovered in sporadic CD [5]. Here, USP48 is linked to Cowden disease.