title: Follow-up Findings in a Turkish Girl with Pseudohypoparathyroidism Type Ia Caused by a Novel Heterozygous Mutation in the GNAS Gene.
abstract: Pseudohypoparathyroidism type Ia (PHP-Ia) is characterized by multihormone resistance and an Albright hereditary osteodystrophy (AHO) phenotype. It is caused by heterozygous mutations inGNASgene. Clinical and biochemical findings of a female PHP-Ia patient were evaluated from age of diagnosis (6.5 years) to 14.5 years of age. The patient had short stature, brachydactyly, and subcutaneous heterotopic ossifications. Serum calcium and phosphorus levels were normal, but parathyroid hormone levels were high. Based on the typical clinical findings of AHO phenotype and biochemical findings, she was diagnosed as having PHP-Ia. A novel heterozygous mutation (c.128T>C) was found in theGNASgene. Follow-up examinations revealed resistance to thyroid-stimulating hormone and a bioinactive growth hormone. Clinicians should take into consideration PHP-Ia in patients referred with short stature, and patients with an AHO phenotype must be further evaluated for hormone resistance,GNASgene mutation, Gsα activity. To our knowledge, this is the first case report describing bioinactive growth hormone in PHP-Ia.
authors.forename: Sezgin
authors.initials: S
authors.lastname: Şahin
authors.forename: Olaf
authors.initials: O
authors.lastname: Hiort
authors.forename: Susanne
authors.initials: S
authors.lastname: Thiele
authors.forename: Olcay
authors.initials: O
authors.lastname: Evliyaoğlu
authors.affiliation: İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Genetics, İstanbul, Turkey Phone: +90 212 4143192 E-mail: beyhan@istanbul.edu.tr.
authors.forename: Beyhan
authors.initials: B
authors.lastname: Tüysüz
mesh_terms: D000293:Adolescent; D002648:Child; D002864:Chromogranins / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D005500:Follow-Up Studies; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D009154:Mutation; D011547:Pseudohypoparathyroidism / Q000145:classification / Q000175:diagnosis / Q000235:genetics*; D014421:Turkey
chemical_list: D002864:Chromogranins; C406732:GNAS protein, human; D019205:GTP-Binding Protein alpha Subunits, Gs