ESPE Abstracts

Background: Loss of function mutations in SGPL1 have previously been described by our group in association with a multisystemic disorder encompassing PAI and nephrotic syndrome. SGPL1 encodes, sphingosine 1-phosphate lyase (SGPL1), which irreversibly binds sphingosine 1-phosphate (S1P) and commits it to the final degradative step in sphingolipid metabolism. SGPL1 is therefore a major modulator of S1P signalling. Several sphingolipid intermediates such as cera...

Background: GH insensitivity (GHI) encompasses growth failure, low serum IGF-1 and normal/elevated serum growth hormone (GH) (basal level >5 μg/L and/or peak on provocation testing >10 μg/L). In a significant number of children the molecular cause is unknown.Objective: To investigate the genetic etiology of GHI in a cohort of children by candidate gene (CGS) and whole exome (WES) sequencing.Methods: About 109 pati...

Sphingosine 1-phosphate lyase insufficiency syndrome (SPLIS) was described in 2017 as a novel condition affecting sphingolipid metabolism, with bi-allelic loss of function mutations in SGPL1. There is a multisystemic phenotype including steroid resistant nephrotic syndrome and primary adrenal insufficiency (PAI) and to a lesser extent ichthyosis, neurological disease and lymphopenia. Hypogonadism is described amongst some affected patients. To interrogate the steroid ...

Background: Loss of function mutations in SGPL1, a key component of sphingolipid metabolism, are associated with accumulation of sphingolipid intermediates giving rise to a multisystemic disease incorporating primary adrenal insufficiency (PAI) and progressive renal and neurological disease. Sphingolipids are implicated in mitochondrial apoptosis via induction of mitochondrial outer membrane permeabilization, cytosolic release of inter-membranal cytochrome c and activ...

Background: Mutations in the human GH receptor gene (GHR) are the most common cause of GH insensitivity (GHI) syndrome and IGF1 deficiency. The extracellular domain of GHR (encoded by exons 2–7 of the GHR gene) can be proteolytically cleaved to circulate as GH-binding protein.Objective: To evaluate the cause of classical GHI (Laron) phenotypes in two siblings and their parents.Method: We observed clinical characteristics of tw...

Background: CYP11A1 gene encodes the cholesterol side-chain cleavage enzyme, P450scc, which plays a key role in the initial steps of steroidogenesis. CYP11A1 insufficiency lead to a variable phenotype ranging from severe early onset primary adrenal insufficiency (PAI) in the neonatal period,with 46,XY DSD; to late-onset PAI with normal genitalia.Objective: Detail the phenotype of a family sharing newly described...

Background: Two siblings of non-consanguineous parents presented with FGD, demonstrated by ACTH resistance with glucocorticoid but not mineralocorticoid deficiency. The proband presented at 21 months, unresponsive with hypoglycaemia (BGL 1.5 mmol/l). Endocrine evaluation subsequent to resuscitation indicated adrenal insufficiency with elevated ACTH. Hydrocortisone therapy was commenced. A sibling, 4 years younger than the proband had a short Synacthen test (SST) performed on d...

Background: Homozygous mutations in STAT5B result in GH insensitivity and immune dysfunction. Heterozygous dominant negative mutations have not been described.Aims and objectives: To characterize genomic STAT5B DNA in two families exhibiting short stature.Methods: Sanger sequencing of STAT5B from genomic DNA. Mutant STAT5B constructs were expressed in HEK293 cells.Results: ...

Background: Primary adrenal insufficiency (PAI) is most commonly congenital in children. PAI is genetically heterogeneous with some gene defects causing syndromic disease. A third of patients have no genetic diagnosis meaning their prognosis is uncertain. We recently investigated families with a novel combination of PAI and steroid resistant nephrotic syndrome.Objective and hypotheses: To discover the genetic defect underlying this syndrome.<p class=...