Germ-line inactivating mutations of the hyperparathyroidism type 2 (HRPT2/CDC73) gene located in chromosomal region 1q31.2 underlie the hereditary hyperparathyroidism-jaw tumor (HPT-JT) syndrome associated with parathyroid tumors in addition to tumors of the jaws and uterus, as well as various kidney lesions [1], [2]. The gene discussed is CDC73; the disease is tumor of parathyroid gland.