ESPE Abstracts

Introduction: Hypochondroplasia (HCH) is a form of mild dwarfism caused by heterozygous gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3). FGFR3 is a negative regulator of endochondral bone growth, and individuals with HCH typically exhibit characteristics such as disproportionate short stature with shortening limb length, lumbar lordosis, and macrocephaly. Regarding recombinant human growth hormone (rhGH) therapy in children with H...

Background: Escobar Syndrome (ES; OMIM #265000) is a rare condition falling under the spectrum of Multiple Pterygium Syndromes (MPS). MPS encompasses a group of congenital anomaly disorders characterized by features such as neck, elbows, and knee webbing alongside joint contractures (arthrogryposis). ES, specifically, represents a non-lethal variant stemming from homozygous or compound heterozygous mutations in the CHRNG gene. Noteworthy characteristics includ...

Background: The calcium-sensing receptor (CaSR) regulates calcium metabolism by modulating PTH secretion, as well as by direct effect on osteoblasts and osteoclasts, balancing bone formation and resorption. Loss-of-function heterozygous mutations on CASR gene can lead to Familial Hypocalciuric Hypercalcemia (FHH; OMIM #145980), a benign autosomal dominant condition of undefined incidence. Dysplasia Epiphysealis Hemimelica (DEH; OMIM #127800) is a rare...

Background: Noonan Syndrome (NS; OMIM 163950) is a common autosomal dominant disorder distinguished by facial dysmorphism, short stature, heart defects, chest deformities, and learning disabilities or mental retardation. NS stems from heterozygous germline causative variants in genes regulating the RAS/MAPK signaling pathway, including PTPN11, SOS1, RAF1, RIT1, KRAS, NRAS, BRAF, LZTR1, and SOS2. The condition exhibits considerable clinical variability and shar...

Background: Noonan syndrome (NS) is a rare genetic disease characterized by facial dysmorphism, short stature, heart defects, chest deformities, and variable developmental delay/learning disabilities. Almost 80% of patients have a mutation in the genes encoding components of the RAS/MAPK pathway. Puberty was described as delayed in NS patients, but few studies are focusing on this subject and genotype-phenotype correlations so far.<s...

Background: Noonan syndrome (NS) is a frequent autosomal dominant disorder characterized by facial dysmorphisms, heart defects, short stature and learning disabilities. It is caused by mutations in genes within the RAS/MAPK signaling pathway, thus called RASopathies. The RAS/MAPK pathway can also impact the signal transduction of hormones involved in body weight, carbohydrate, and lipid metabolism features scarcely studied only in animal models. This study aimed to describe me...

Background: Familial Hypocalciuric Hypercalcemia (FHH) type 1 is a benign condition of hypercalcemia with autosomal dominant inheritance caused by pathogenic variants in the calcium-sensing receptor gene (CASR). CaSR plays a crucial role in the regulation of calcium balance. Inactivating mutations in CASR result in altered calcium-sensing and inappropriate parathyroid hormone (PTH) release concerning the calcium concentration. Dysplasia Epiph...

Objective: To evaluate the response to recombinant human GH (rhGH) treatment in NS children with short stature and previously identified mutations in the RAS/MAPK pathway genes.Methods: 23 patients with NS (17 males; 19 PTPN11, 3 RAF1 e 1 SHOC2) were daily treated with rhGH (mean rhGH dose of 47 μg/kg per day). The main outcome measures were 1st year growth velocity, change in height SDS (Noonan syndrome specifi...

Introduction: Noonan syndrome (NS) is a relative frequent genetic disorder, mainly characterized by dysmorphic face features, congenital heart defects and short stature. Though delayed pubertal development has been described in both sexes, the physiopathological root remains unclear. This study aims at characterizing puberty development in Noonan syndrome.Materials and Methods: The study population included 111 individuals with a molecul...

Background: Patients born small for gestational age (SGA) with additional syndromic features to short stature are likely to present with genetic causes.Aim: To perform a clinical and genetic-molecular investigation of a group of syndromic SGA patients without catch-up growth.Methods: We selected 118 patients born SGA [birth weight and/or length standard deviation score (SDS) ≤−2 for gestational age] without catch-up gro...