Abstract
Pseudohypoparathyroidism type 1A (PHP1A), a rare hereditary disorder, is featured by end-organ resistance to parathyroid hormone and Albright's hereditary osteodystrophy. Heterozygous mutation of guanine nucleotide-binding protein α stimulating (GNAS) gene causes the half decreased bioactivity of the Gsα protein levels. Due to the diverse early clinical manifestations of PHP1A, a diagnosis of PHP1A is often easily overlooked and misdiagnosis or missed diagnosis is common. The present study described a girl who was initially diagnosed with hereditary multiple exostoses, but was afterwards confirmed with PHP1A. Moreover, genetic analysis indicated a new mutation (c2277deIC) of the gene.