Hypoparathyroidism is characterized by hypocalcemia and hyperphosphatemia due to inadequate supply or effectiveness of circulating parathyroid hormone (PTH).
Isolated hypoparathyroidism is caused by disease-causing variants in the AIRE, CASR, GATA3, GCM2, GNA11, PTH and TBCE genes (Sunthornthepvarakul et al 1999 J Clin Endocrinol Metab 84:3792-3796; Pollak et al 1994 Nat Genet 8:303-307; Baumber et al 2005 J Med Genet 42:443-448; Nesbit et al, 2013, New Eng. J. Med. 368: 2476-2486).
NHSE test directory code: R153 Familial hypoparathyroidism. Testing criteria can be found on this webpage: https://www.england.nhs.uk/publication/national-genomic-test-directories/.