Indications for genetic testing for inheritable parathyroid disease include patientsyounger than 30 years old with PHPT; those with multigland disease on imaging orhistory; those with a family history of hypercalcemia or syndromic disease such asMEN1, MEN2A, MEN4 or hyperparathyroidism–jaw tumor syndrome and those withatypical parathyroid adenoma and parathyroid carcinoma (7). Here, CDKN1B is linked to hypercalcemia disease.