Autosomal dominant pseudohypoparathyroidism type 1B due to STX16 deletion: a case presentation and literature review

Pseudohypoparathyroidism (PHP) is a heterogeneous group of rare, genetically related, endocrine disorders, characterized by end-organ resistance to parathyroid hormone (PTH) action and other G protein-coupled receptors (GPCRs) related hormones. The clinical variants of PHP are classified according to the presence of features of Albright's hereditary osteodystrophy (AHO) and in vivo response to exogenous PTH. Autosomal dominant PHP1b is often caused by a deletion in the syntaxin-16 (STX16) gene, leading to a loss of methylation in the A/B exon of the guanine nucleotide-binding protein a-stimulating polypeptide (GNAS) complex. Herein, we present a case of a 41-year-old man with familiar PHP1b due to a maternal inherited 3-kb STX16 deletion, who was referred to us for consultation by artificial reproductive technology specialists.