ESPE Abstracts

17β-Hydroxysteroid dehydrogenase type 3 (17β-HSD3) is expressed mostly in the testes and converts the inactive Δ4-androstenedione (A) to testosterone (T). 17β-HSD3 deficiency is a rare autosomal recessive disorder and the most common testosterone biosynthesis defect leading to 46,XY Disorders of Sex Development (DSD). To date, more than 40 mutations of HSD17B3 have been reported. 46,XY patients with 17β-HSD3 deficiency would present with wide variable ...

Introduction: Pseudohypoaldosteronism type II (PHA II) is an extremely rare disorder characterized by low plasma renin and aldosterone when a normal renal function with hypertension, hyperkalemia, and hyperchloremic metabolic acidosis. PHA II is also known as familial hyperkalemic hypertension or Gordon’s syndrome and is an inherited autosomal dominant. PHA II could be caused by pathogenic variants of WNK1, WNK4, KLHL3, and <em...

Background: Mutations in CHD7 cause a rare multi-organ system disorder, CHARGE syndrome (CS). Genital hypoplasia has been described in 60-80% of reported cases because of idiopathic hypogonadotropic hypogonadism (IHH), which is a result of inadequate GnRH secretion in the hypothalamus. Correspondingly, IHH and anosmia are expected in cases with CHD7 mutation. However, due to the phenotypic spectrum of CHD7, mutations have also be...

BMP4, a member of the bone morphogenetic protein family which is part of the transforming growth factor-beta superfamily, is involved in the embryonic development of various organ and tissues including the cranio-facial structures, olfactory placode, pituitary, eyes, heart, and kidneys. Mutations in this gene are associated with orofacial cleft and microphthalmia in human patients. BMP4 plays an important role in the embryonic development of the GnRH neurons ...

Background: GnRH neurons originate outside the CNS in the olfactory placode and migrate into the central nervous system, becoming integral components of the hypothalamic-pituitary–gonadal axis (HPG).Objective and hypotheses: We hypothesize that gene(s), whose products are important for pubertal development can be identified via autozygosity mapping together with whole exome sequencing in patients with idiopathic hypogonadotrophic hypogonadism (IHH)/...

Background: What initiates pubertal process in humans and other mammals has remained elusive.Objective and hypotheses: We hypothesize that gene(s), whose products trigger the GnRH pulse generator to restart ticking at the usual time of puberty, can be identified via autozygosity mapping together with whole exome sequencing in patients with idiopathic hypogonadotrophic hypogonadism (IHH).Method: We studied a cohort IHH cases. Functi...

Background: Idiopathic hypogonadotropic hypogonadism (IHH) is characterised by failure of initiation or maintenance of puberty due to insufficient gonadotropin release, which is not associated with anosmia/hyposmia.Objective and hypotheses: The objective of this study was to determine the distribution of causative mutations in an hereditary form of IHH.Method: In this prospective collaborative study, families with more than one aff...

Background: P450 oxidoreductase (POR) deficiency is a rare cause of congenital adrenal hyperplasia (CAH) with a wide spectrum of clinical phenotypes including glucocorticoid deficiency, difference/disorder of sex development (DSD), skeletal malformations, and Antley-Bixler syndrome. We describe the clinical and molecular characteristics of a large cohort with POR deficiency with long-term data.Methods: The medical record...

Background: Vitamin D Dependent Rickets Type IA(VDDR1a) is an autosomal recessive disorder characterized by defects in the biosynthesis of its active form 1,25 dihydroxyvitamin D due to the mutations in the CYP27B1 gene encoding for the enzyme 1α-hydroxylase.Objective and hypotheses: To evaluatethe clinical characteristics, molecular genetics aetiology and long-term outcome of a large nationwide cohort of VDDR-Ia f...

Objective: Congenital Hyperinsulinism(CHI) is a clinically, genetically, and histologically heterogeneous disease. Turkey is a county with highly prevalent cases of severe CHI due to the high rate of consanguinity and recessively inherited KATP gene mutations. We herein evaluated the clinical characteristics, molecular genetic analysis, and follow-up of a large nationwide cohort of CHI from Turkey.Patients and method: Th...