Mutation of CDC73 results in corresponding loss of H2B monoubiquitination in both in vitro and in vivo. Mutated or abnormally regulated CDC73 has been reported in parathyroid, renal, breast, gastric, and colorectal tumors, as well as in the germline of patients with the familial disorder-hyperparathyroidism jaw tumor syndrome [116]. The gene discussed is CDC73; the disease is hyperparathyroidism.