A novel gain-of-function mutation (W818R) of calcium-sensing receptor in a family with autosomal dominant hypocalcemia type 1

Introduction Autosomal dominant hypocalcemia type 1 (ADH1) is a rare inherited disorder caused by gain-of-function mutations in the calcium-sensing receptor ( CASR ) gene, with clinical manifestations ranging from asymptomatic hypocalcemia to recurrent seizures. Methods Clinical evaluation and genetic testing were performed. Through activation of the MAPK signaling pathway,cellular functional validation was conducted to confirm the pathogenicity of this variant. Results We report a two-generatio