ESPE Abstracts

Introduction: Neonatal Diabetes Mellitus (NDM) is characterised by severe hyperglycaemia, usually diagnosed in the first 6 months of life. Genetic diagnosis helps distinguishing between its different causes and between transient (TNDM) and permanent (PNDM) forms, with repercussions on the therapeutic approach and follow-up.Aim: Clinical and molecular characterisation of a series of NMD cases under endocrinological follow...

Background: Homozygous natriuretic peptide receptor-2 (NPR2) mutations cause acromesomelic dysplasia, type Maroteaux, a skeletal dysplasia with extreme disproportionate short stature and recently, heterozygous NPR2 mutations have been identified also in patients with idiopathic short stature (ISS, 2–6%). SHOX mutations are found in ~2–5% of ISS cases and ~70% of Léri-Weill dyschondrosteosis (LWD) cases, characterized by disproportionat...

Background: The MAMLD1 gene (Xp28) is thought to cause disorder of sex development (DSD) in 46, XY patients, mostly presenting with hypospadias, and, recently, also gonadal dysgenesis. However, there is some controversy about the role of MAMLD1 in sex development because i) some MAMLD1 variants are also detected in normal individuals, ii) others are not present in all affected DSD individuals of the same family; iii) several MAMLD1 mutations...

Background: Mutations in SHOX or its regulatory regions have been detected in ~70% of Léri-Weill dyschondrosteosis (LWD) and ~2.5% of idiopathic short stature (ISS) cases, suggesting the implication of other genes or loci. Recent studies have identified NPR2 defects in ISS patients.Objective and hypotheses: To investigate if NPR2 mutations can account for a proportion of the cases referred for LWD and ISS in whom no SHOX/PAR1 mutation was detected.<...

Introduction: Variants in the N-terminal of the Indian-hedgehog gene (IHH) have been associated with Brachydactyly type-A1 (AD) and Acrocapitofemoral dysplasia (AR), only three of which have been functionally studied. However, heterozygous IHH variants, majority classified as variants of unknown significance (VUS) are being increasingly identified, not only in the N-terminal but also in the uncharacterized C-terminal, by NGS, in individuals with short...

Background and Aims: HNF4A-MODY clinical expression is broad, ranging from hypoglycemic hyperinsulinism in the neonatal period and early childhood to hyperglycemia and diabetes, as insulin secretion progressively decreases in adult patients. The main objective was to clinically and molecularly characterize patients with glycemic alterations, negative autoimmunity and confirmed molecular diagnosis of HNF4A-MODY.Materials and Metho...

Background: GL1I2 encodes a zinc-finger transcription factor expressed in the developing hypothalamus and in Rathke's pouch, the embryonic precursor of the pituitary gland. Pathogenic GL1I2 variants have been implicated in the etiology of the broad clinical spectrum of congenital hypopituitarism (CHY): holoprosencephaly, midline facial abnormalities, Culler-Jones syndrome, combined pituitary hormone-deficiency (CPHD) and isolated GH-defi...

Background: IGF1 resistance syndrome (IGF1RS) is characterized by intrauterine and postnatal growth deficit with normal or supranormal IGF1 levels. Additional features may include intellectual deficit, microcephaly and dysmorphisms. IGF1RS may be caused by genomic or genetic defects affecting the IGF1R locus (15q26.3).Objective and hypotheses: To investigate the frequency of IGF1R mutations in a cohort of patients with pre- and/or postn...

Background: A total of 456 skeletal dysplasias have been classified by molecular, biochemical and/or radiological criteria, into 40 groups. Despite this, the precise, final diagnosis is often difficult due to the high phenotypic and genotypic variability.Objective: To improve the molecular and clinical diagnosis of skeletal dysplasias using a custom-designed next-generation sequencing (NGS) panel.Method: A total of 56 skeletal dysp...

Background: Although isolated GH deficiency (IGHD) is one of the most frequent causes of postnatal proportional undergrowth, up to 85–90% of IGHD cases are still classified as idiopathic. On the other hand, previous reports identified up to 40 different GH1 proximal promoter haplotypes, some of which show hypomorphic effects, significantly reducing GH1 expression levels.Objective and hypotheses: To investigate the frequency of ...