To determine the incidence, natural history, and mechanism of C cell dysfunction in PHP, calcitonin assays were performed in six patients with PHP Ia and four with pseudopseudohypoparathyroidism from three unrelated families.
This finding, in conjunction with previous studies demonstrating the role of Ste20/PAK kinases in heterotrimeric G protein signaling, suggests that STK25 is a positional candidate gene for PPHP.
This finding, in conjunction with previous studies demonstrating the role of Ste20/PAK kinases in heterotrimeric G protein signaling, suggests that STK25 is a positional candidate gene for PPHP.
Mutations of the GNAS1 gene, which is located on chromosome 20q13.11 and encodes the alpha-subunit of the stimulatory GTP-binding protein, have been identified in patients with pseudohypoparathyroidism type Ia (PHPIa) and pseudopseudohypoparathyroidism (PPHP).
A mother with pseudopseudohypoparathyroidism and her short son showed poor spontaneous growth hormone secretion, and provocation tests suggested a deficiency of growth hormone releasing factor.
To determine the incidence, natural history, and mechanism of C cell dysfunction in PHP, calcitonin assays were performed in six patients with PHP Ia and four with pseudopseudohypoparathyroidism from three unrelated families.
To determine the incidence, natural history, and mechanism of C cell dysfunction in PHP, calcitonin assays were performed in six patients with PHP Ia and four with pseudopseudohypoparathyroidism from three unrelated families.
To determine the incidence, natural history, and mechanism of C cell dysfunction in PHP, calcitonin assays were performed in six patients with PHP Ia and four with pseudopseudohypoparathyroidism from three unrelated families.
An adult woman with pseudopseudohypoparathyroidism had a child with normal calcium and parathyroid hormone concentrations and cyclic AMP response to injected parathyroid hormone in infancy.
An adult woman with pseudopseudohypoparathyroidism had a child with normal calcium and parathyroid hormone concentrations and cyclic AMP response to injected parathyroid hormone in infancy.
AHO refers to the phenotype of the syndromes of pseudo-hypoparathyroidism (PHP) type Ia and pseudopseudohypoparathyroidism (PPHP), both considered genetically related variants with a defect of the alpha subunit of the stimulatory G protein of adenylate cyclase, necessary for the action of parathyroid and other hormones using cyclic AMP as an intracellular second messenger.
AHO refers to the phenotype of the syndromes of pseudo-hypoparathyroidism (PHP) type Ia and pseudopseudohypoparathyroidism (PPHP), both considered genetically related variants with a defect of the alpha subunit of the stimulatory G protein of adenylate cyclase, necessary for the action of parathyroid and other hormones using cyclic AMP as an intracellular second messenger.
Cell membranes from patients with PHP type Ia and from patients with pseudoPHP contained levels of immunoactive Gs alpha that were equivalently reduced (43 +/- 4% vs. 42 +/- 5%, respectively).
Cell membranes from patients with PHP type Ia and from patients with pseudoPHP contained levels of immunoactive Gs alpha that were equivalently reduced (43 +/- 4% vs. 42 +/- 5%, respectively).
Cell membranes from patients with PHP type Ia and from patients with pseudoPHP contained levels of immunoactive Gs alpha that were equivalently reduced (43 +/- 4% vs. 42 +/- 5%, respectively).
PHP and PPHP are etiologically linked and caused by genetic and/or epigenetic alterations in the guanine nucleotide-binding protein alpha-stimulating (G<sub>s</sub> α) locus (GNAS) in chromosome 20q13.
Stimulatory guanine nucleotide binding protein subunit 1 mutation in two siblings with pseudohypoparathyroidism type 1a and mother with pseudopseudohypoparathyroidism.
An inherited mutation associated with functional deficiency of the alpha-subunit of the guanine nucleotide-binding protein Gs in pseudo- and pseudopseudohypoparathyroidism.
Pseudohypoparathyroidism type Ia (PHP Ia) comprises the clinical features of AHO associated with parathyroid hormone (PTH) resistance while pseudo-pseudohypoparathyroidism (PPHP) includes AHO features without PTH resistance.
Maternal transmission of Gs(alpha) mutations leads to AHO plus resistance to several hormones (e.g., parathyroid hormone) that activate Gs in their target tissues (pseudohypoparathyroidism type IA), while paternal transmission leads only to the AHO phenotype (pseudopseudohypoparathyroidism).
Different inactivating mutations of the gene GNAS1 encoding Gsalpha lead to a reduced Gsalpha protein activity in patients with AHO and pseudohypoparathyroidism type Ia or without resistance to PTH (pseudopseudohypoparathyroidism).
Pseudohypoparathyroidism (PHP) refers to two major variants that generally coexist in the same family, PHP type Ia (PHP Ia), in which both PTH resistance and a constellation of physical features, termed Albright's hereditary osteodystrophy (AHO), are present, and pseudopseudohypoparathyroidism (PPHP), in which AHO occurs without PTH resistance.