A Woman and Her Father with Calcium-Sensing Receptor Mutation and Autosomal Dominant Hypocalcemia

ABSTRACT Objective: To discuss the case of a woman and her father with autosomal dominant hypocalcemia (ADH), a rare disorder caused by an activating mutation of the calcium-sensing receptor (CaSR). Methods: Previous ADH case reports were obtained by Medline search and from an updated CaSR database. Results: A 37-year-old female presented with intermittent leg cramps and hypocalcemia. Her father had been previously diagnosed with asymptomatic hypocalcemia at age 54. Genetic analysis in both individuals revealed identical missense mutations in nucleotide c.2489G>A that resulted in a glycine to aspartic acid change at codon 830 (G830D) in the CaSR. Conclusion: The same mutation of the CaSR gene was identified in a woman and her father. This warrants the need for genetic testing in adults with mild hypocalcemia and a family history of hypocalcemia. Abbreviations: ADH = autosomal dominant hypocalcemia CaSR = calcium-sensing receptor iPTH = intact parathyroid hormone OMIM = Online Mendelian Inheritance in Man TMD = transmembrane domain