Endocrine Abstracts

Introduction: Pseudohypoparathyroidism type 1A (PHP1A) is a rare genetic disease characterized by resistance to parathyroid hormone along with hormonal resistance and features of Albright hereditary osteodystrophy (AHO). This is caused by heterozygous inactivating mutations in the maternal allele of the GNAS gene, which encodes the stimulatory G-protein alpha subunit (Gsα) and regulates production of second messenger cyclic AMP. Here, we report a previously undescribed GN...

Introduction: The insulin-like growth factor 1 receptor (IGF1R) gene, located on chromosome 15q26.3, encodes the 1367 aa tyrosine kinase receptor IGF1R which is involved in many processes, including growth. Few heterozygous mutations of IGF1R leading to IGF-I resistance have been described in patients with intrauterine and postnatal growth retardation, microcephaly and variable learning difficulties. We report previously undescribed IGF1R nonsense variant in a child with norma...

Introduction: 11-beta-dehydroxysteroid dehydrogenase-1 (11BHSD1) is a bidirectional enzyme which converts inactive cortisone and 11-dehydrocorticosterone to active cortisol and corticosterone and vice-versa. The direction is dependent on NADPH availability and the action of the cofactor enzyme hexose-6-phosphate dehydrogenase (H6PDH). Cortisone reductase deficiency is a rare disorder caused by defects in 11BHSD1 or H6PDH, leading to inability to regenerate act...

Background: Congenital hyperinsulinism (CHI) is a heterogeneous genetically determined condition that is characterised by unregulated secretion of insulin from pancreatic β-cells. The most common and severe cases are caused by mutations in the ABCC8 gene encoding the SUR1 subunit of the KATP channel subunit. Autosomal recessive mutations in HADH gene are a rare cause of CHI. The advances in CRISPR/Cas9 gene editing technology has enabled the i...

Background: Congenital Hyperinsulinism (CHI) is characterized by the unregulated secretion of insulin in the presence of hypoglycaemia. The mutations in ABCC8 and KCNJ11, which encode the sulfonylurea receptor 1 (SUR1) and potassium inward-rectifying 6.2 (Kir6.2) subunits of ATP-sensitive potassium channel (K channel), are the most common identified cause of the condition.Aims: The aim is to use the novel CRISPR/Cas9 gene editing technique to create a KO...

Introduction: Heterozygous inactivating mutations in the maternal allele of the GNAS gene typically result in pseudohypoparathyroidism (PHP). GNAS variants were recently described in 1% of patients, not known to have PHP, in the UK Genetics of Obesity cohort, resulting in reduced MC4R signalling and variable effects on PTH-R and GHRH-R signalling.Methods: NGS (Cambridge Obesity Gene Panel) and in vitro functiona...

Background: The CRISPR/Cas9 genome-editing platform is a powerful technology to create genetically engineered cells and organisms. However, the success of CRISPR genome editing experiments is limited by the intracellular delivery and expression of Cas9 endonuclease protein and guide RNA (gRNA). Beta-tumour cells (βTC-6), derived from transgenic mice, exhibit glucose stimulated insulin secretion which makes them a valuable tool in understanding the mechanisms that regulate...

Background: Congenital Hyperinsulinism (CHI) is characterized by the unregulated secretion of insulin in the presence of hypoglycaemia. The mutations in ABCC8 and KCNJ11, which encode the sulfonylurea receptor 1 (SUR1) and potassium inward-rectifying 6.2 (Kir6.2) subunits of ATP-sensitive potassium channel (K channel), are the most common identified cause of the condition. Defects in the HADH gene are responsible for SCHAD-HI, a rare form of the disease caused by the disruptio...