Heritable hyperparathyroidism: Genetic insights and clinical implications.

Familial or heritable hyperparathyroidism (FHPT) is seen in approximately 10-15 % of patients with primary hyperparathyroidism (PHPT). Once the diagnosis of PHPT is established, consideration of heritable forms should be made in patients with positive family history, young onset, multi-glandular disease, and recurrent or persistent disease. FHPT encompasses both syndromic and non-syndromic forms. Syndromic forms include multiple endocrine neoplasia (MEN) types 1, 2, 3 and 4, hyperparathyroidism-jaw tumor syndrome, hereditary pheochromocytoma and paraganglioma, and the more recently reported, Birt-Hogg-Dubé (BHD) syndrome, and X-linked intellectual disability syndrome. Non-syndromic forms include familial hypocalciuric hypercalcemia (FHH)- types 1,2, and 3, neonatal severe hyperparathyroidism, GCM2-mediated hyperparathyroidism, transient neonatal hyperparathyroidism, and familial isolated hyperparathyroidism. In this review we aim to review the heritable forms of PHPT and highlight the important genetics insights and clinical implications.