ESPE Abstracts

Background: We previously reported the first human mutation in mini-chromosome maintenance homologue 4 (MCM4) in a cohort of patients with adrenal failure, immunodeficiency and chromosomal fragility.Objective and Hypotheses: To report the full endocrine phenotype of 14 patients with MCM4 mutations.Method: Patients case notes were examined and investigations performed to fully assess adrenal function, pubertal development, gonadal f...

Background: Mutations in the side chain cleavage enzyme, (CYP11A1) cause congenital adrenal insufficiency, with complete or partial 46XY sex reversal. The disorder manifests with adrenal and gonadal insufficiencies along with derangements of the renin/angiotensin system.Objective and hypotheses: To obtain a genetic diagnosis in six patients with adrenal insufficiency of unknown aetiology. Patients 1 and 2 are sisters with ACTH resistance, having...

Background: Familial glucocorticoid deficiency (FGD) is a rare and potentially life-threatening disease, characterized by adrenal insufficiency without mineralocorticoid deficiency. It is diagnosed during the neonatal period but also in childhood. Manifestations are recurrent hypoglycemia, seizures or even coma, chronic fatigue, recurrent infections and skin hyperpigmentation. Mutations on mineralocorticoid receptor 2 (MC2R) gene and on melanocortin-2 receptor accesso...

Background: In humans, loss-of-function mutations in Nicotinamide nucleotide transhydrogenase (NNT) cause familial glucocorticoid deficiency, a potentially fatal, adrenal-specific disorder characterized by increased ACTH and reduced cortisol levels. NNT is a highly conserved inner mitochondrial membrane protein, which supplies high concentrations of NADPH for detoxification of reactive oxygen species (ROS) by glutathione and thioredoxin pathways.<p class="abstext"...

Introduction: The molecular aetiology of familial glucocorticoid deficiency (FGD) is very heterogeneous. A recent report of a genetic variant in TXNRD2, the gene encoding thioredoxin reductase Type 2, in a South Asian kindred with FGD suggests that the maintenance of redox balance may be critical for adrenocortical function. We present the second report of an individual from another south Asian family harbouring a different pathological variant in <em...

Background: Pathogenic IGFI gene mutations causing childhood growth failure are rare. Only 5 autosomal recessive mutations, one IGFI copy number variant and 2 heterozygous frameshift mutations are reported. Heterozygous missense IGFI mutations have not previously been described.Objectives: To identify and functionally characterise a novel missense IGFI variant in a patient with postnat...

Background: SGPL1 deficiency is associated with a pathological accumulation of sphingolipid intermediates and a multi-systemic condition incorporating primary adrenal insufficiency. Sphingolipid intermediates such as ceramide, sphingosine and sphingosine 1-phosphate are postulated to act as modulators of the steroidogenic pathway, often acting as second messengers altering downstream expression of steroid responsive transcriptional elements. Ceramide and sphin...

Background: Growth Hormone Insensitivity (GHI) is usually caused by mutations in the Growth Hormone receptor (GHR). Patients present with short stature associated with high GH and low IGF-I levels and often have midfacial hypoplasia (typical Laron syndrome facial features). Our centre previously described the first GHR pseudoexon mutation (42700896A>G, c. 618+792A>G). The inclusion of this 108bp pseudoexon is predicted to lead to in-frame insertion of...

Background: Growth hormone insensitivity (GHI) encompasses normal/elevated growth hormone (GH), low IGF-I levels and growth restriction. Non-classical/mild-moderate GHI is an emerging entity which is poorly characterised, and, in many subjects, the underlying cause is unclear. Heterozygous dominant negative (DN) variants located in the intracellular/transmembrane domain of the GH receptor (GHR) cause a ‘non-classical’ GHI phenotype.<p class="abst...

Background: Noonan syndrome (NS) is caused by variants in multiple genes regulating the RAS/MAPK signalling cascade. NS can present with growth failure associated with growth hormone insensitivity (GHI; low IGF-I and normal/elevated GH levels). Variants in LZTR1 lead to NS, although the interaction of LZTR1 with the RAS/MAPK and the GH-IGF-1 pathways remain to be elucidated.Objectives: To gain insights into the ...