Identification of a Novel Calcium-Sensing Receptor Gene Mutation Causing Familial Hypocalciuric Hypercalcemia by Single-Strand Conformation Polymorphism Analysis

Abstract

Calcium-sensing receptor gene (CASR) mutations that alter the function of the G protein coupled Ca²⁺-sensing receptor are reported in patients with familial hypocalciuric hypercalcemia (FHH), autosomal dominant hypocalcemia (ADH), and neonatal severe hyperparathyroidism (NSHPT). In search for novel disease causing mutations in the CASR gene, we screened exons 2 - 7 of the CASR gene of a family with FHH using single-strand conformation polymorphism analysis. We identified a novel CASR mutation (c.518 T > C; L173 P) in exon 4 encoding for the extracellular domain of the Ca²⁺-sensing receptor. This region seems to represent a hot spot within the CASR gene with at least 13 reported disease causing mutations thus far.

Calcium-sensing receptor - familial hypocalciuric hypercalcemia

References

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