Highly Conserved Non-Coding Sequences and the 18q Critical Region for Short Stature: A Common Mechanism of Disease?

Background. Isolated growth hormone deficiency (IGHD) and multiple pituitary hormone deficiency (MPHD) are heterogeneous disorders with several different etiologies and they are responsible for most cases of short stature. Mutations in different genes have been identified but still many patients did not present mutations in any of the known genes. Chromosomal rearrangements may also be involved in short stature and, among others, deletions of 18q23 defined a critical region for the disorder. No gene was yet identified. Methodology/Principal Findings. We now report a balanced translocation X;18 in a patient presenting a breakpoint in 18q23 that was surprisingly mapped about 500 Kb distal from the short stature critical region. It separated from the flanking SALL3 gene a region enriched in highly conserved non-coding elements (HCNE) that appeared to be regulatory sequences, active as enhancers or silencers during embryonic development. Conclusion. We propose that, during pituitary development, the 18q rearrangement may alter expression of 18q genes or of X chromosome genes that are translocated next to the HCNEs. Alteration of expression of developmentally regulated genes by translocation of HCNEs may represent a common mechanism for disorders associated to isolated chromosomal rearrangements. © 2008 Rizzolio et al

Characterization of Two Novel Variants of the Steroidogenic Acute Regulatory Protein Identified in a Girl with Classic Lipoid Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia (CAH) consists of several autosomal recessive disorders that inhibit steroid biosynthesis. We describe a case report diagnosed with adrenal insufficiency due to low adrenal steroids and adrenocorticotropic hormone excess due to lack of cortisol negative feedback signaling to the pituary gland. Genetic work up revealed two missense variants, p.Thr204Arg and p.Leu260Arg in the STAR gene, inherited by both parents (non-consanguineous). The StAR protein supports CYP11A1 enzyme to cleave the side chain of cholesterol and synthesize pregnenolone which is metabolized to all steroid hormones. We used bioinformatics to predict the impact of the variants on StAR activity and then we performed functional tests to characterize the two novel variants. In a cell system we tested the ability of variants to support cholesterol conversion to pregnenolone and measured their mRNA and protein expression. For both variants, we observed loss of StAR function, reduced protein expression and categorized them as pathogenic variants according to guidelines of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. These results fit the phenotype of the girl during diagnosis. This study characterizes two novel variants and expands the list of missense variants that cause CAH

Abnormalities of pubertal development and gonadal function in Noonan syndrome

BackgroundNoonan syndrome (NS) is a genetic multisystem disorder characterised by variable clinical manifestations including dysmorphic facial features, short stature, congenital heart disease, renal anomalies, lymphatic malformations, chest deformities, cryptorchidism in males.MethodsIn this narrative review, we summarized the available data on puberty and gonadal function in NS subjects and the role of the RAS/mitogen-activated protein kinase (MAPK) signalling pathway in fertility. In addition, we have reported our personal experience on pubertal development and vertical transmission in NS.ConclusionsAccording to the literature and to our experience, NS patients seem to have a delay in puberty onset compared to the physiological timing reported in healthy children. Males with NS seem to be at risk of gonadal dysfunction secondary not only to cryptorchidism but also to other underlying developmental factors including the MAP/MAPK pathway and genetics. Long-term data on a large cohort of males and females with NS are needed to better understand the impact of delayed puberty on adult height, metabolic profile and well-being. The role of genetic counselling and fertility related-issues is crucial

Real life long-term efficacy and safety of rhGH therapy in children with SHOX deficiency

Objective: This Italian survey aims to evaluate real-life long-term efficacy and safety of rhGH therapy in children with short stature homeobox-containing gene deficiency disorders (SHOX-D) and to identify potential predictive factors influencing response to rhGH therapy. Design and methods: This is a national retrospective observational study collecting anamnestic, anthropometric, clinical, instrumental and therapeutic data in children and adolescents with a genetic confirmation of SHOX-D treated on rhGH. Data were collected at the beginning of rhGH therapy (T0), yearly during the first 4 years of rhGH therapy (T1, T2, T3, T4) and at near-final height (nFH) (T5), when available. Results: 117 SHOX-D children started rhGH therapy (initial dose 0.23 ± 0.04 mg/kg/week) at a mean age of 8.67 ± 3.33years (74% prepubertal), 99 completed the 1st year of treatment, and 46 reached nFH. During rhGH therapy, growth velocity (GV) SDS and height (H) SDS improved significantly. Mean H SDS gain from T0 was +1.14±0.58 at T4 and +0.80 ± 0.98 at T5. Both patients carrying mutations involving intragenic SHOX region (group A) and ones with regulatory region defects (group B) experienced a similar beneficial therapeutic effect. The multiple regression analysis identified the age at the start of rhGH treatment (β -0.31, p = 0.030) and the GV during the first year of rhGH treatment (β 0.45, p = 0.008) as main independent predictor factors of height gain. During rhGH therapy, no adverse event of concern was reported. Conclusions: Our data confirm the efficacy and safety of rhGH therapy in SHOX-D children, regardless the wide variety of genotype

Central Precocious Puberty in Italian Boys: Data From a Large Nationwide Cohort

Context: There are only a few nationwide studies on boys with central precocious puberty (CPP) and the last Italian study is a case series of 45 boys that dates back to 2000. Objective: We aimed to evaluate the causes of CPP in boys diagnosed during the last 2 decades in Italy and the relative frequency of forms with associated central nervous system (CNS) abnormalities on magnetic resonance imaging (MRI) compared to idiopathic ones. Methods: We performed a national multicenter retrospective study collecting data from 193 otherwise normal healthy boys with a diagnosis of CPP. Based on MRI findings, the patients were divided into: Group 1, no CNS abnormalities; Group 2, mild abnormalities (incidental findings) unrelated to CPP; and Group 3, causal pathological CNS abnormalities. Results: The MRI findings show normal findings in 86%, mild abnormalities (incidental findings) in 8.3%, and causal pathological CNS abnormalities in 5.7% of the cases. In Group 3, we found a higher proportion of patients with chronological age at diagnosis < 7 years (P = .00001) and body mass index greater than +2 SDS (P < .01). Gonadotropin-releasing hormone analogue therapy was started in 183/193 subjects. The final height appeared in the range of the target height in all groups and in 9 patients in whom the therapy was not started. Conclusion: In our study on a large nationwide cohort of boys referred for precocious puberty signs, the percentage of forms associated with CNS abnormalities was one of the lowest reported in the literature

Fertility preservation for female patients with childhood, adolescent, and young adult cancer:recommendations from the PanCareLIFE Consortium and the International Late Effects of Childhood Cancer Guideline Harmonization Group

Female patients with childhood, adolescent, and young adult cancer are at increased risk for fertility impairment when treatment adversely affects the function of reproductive organs. Patients and their families desire biological children but substantial variations in clinical practice guidelines reduce consistent and timely implementation of effective interventions for fertility preservation across institutions. As part of the PanCareLIFE Consortium, and in collaboration with the International Late Effects of Childhood Cancer Guideline Harmonization Group, we reviewed the current literature and developed a clinical practice guideline for fertility preservation in female patients who were diagnosed with childhood, adolescent, and young adult cancer at age 25 years or younger, including guidance on risk assessment and available methods for fertility preservation. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to grade the available evidence and to form the recommendations. This clinical practice guideline leverages existing evidence and international expertise to develop transparent recommendations that are easy to use to facilitate the care of female patients with childhood, adolescent, and young adult cancer who are at high risk for fertility impairment. A complete review of the existing evidence, including a quality assessment, transparent reporting of the guideline panel's decisions, and achievement of global interdisciplinary consensus, is an important result of this intensive collaboration.info:eu-repo/semantics/publishe

Gilsanz V. Differential effect of marrow adiposity and visceral and subcutaneous fat on cardiovascular risk in young, healthy adults

Background—Adipose tissue is an endocrine organ that influences many metabolic processes and accumulates in different depots, including the bone marrow. While the negative associations between visceral fat (VF) or subcutaneous fat (SF) and cardiovascular disease (CVD) risks are well known, the relation between marrow fat (MF) and metabolic risk is unexplored. Objectives—We examined the relations between these three fat depots and whether CVD risks are associated to marrow adiposity. Design—observational cross sectional study Subjects and Methods—Computed tomography was used to measure VF, SF and MF depots in 131 healthy young adults (60 females, 71 males; 16-25 years of age). Weight, body mass index (BMI), waist and hip circumferences, blood pressure (BP), carotid intima media thickness (CIMT) and serum levels of lipids, glucose and insulin were also measured. Results—Regardless of gender, MF was not associated to values of VF or SF, anthropometric measures, or lipid or carbohydrate serum levels (P&gt;0.05 for all). In contrast, VF was associated to SF (r’s = 0.74 for females, 0.78 for males; both P’s &lt;0.0001) and these depots were related to anthropometric parameters (r’s between.69 and.87; all P’s &lt;0.0001) and to most measures of lipids, glucose or insulin (r’s between.25 and.62). Conclusions—Marrow adiposity in young men and women is independent of visceral and subcutaneous fat, and is not associated to CVD risk. These findings do not support the concept that marrow adiposity is involved in the comorbidities related to fat accumulation in other compartments. Keywords marrow fat; visceral fat; subcutaneous fat; cardiovascular risk; computed tomograph

Update on bone density measurements and their interpretation in children and adolescents

Following the increased awareness about the central role of the pediatric age in building bone for life, clinicians face more than ever the necessity of assessing bone health in pediatric subjects at risk for early bone mass derangements or in healthy children, in order to optimize their bone mass accrual and prevent osteoporosis. Although the diagnosis of osteoporosis is not made solely upon bone mineral density measurements during growth, such determination can be very useful in the follow-up of pediatric patients with primary and secondary osteoporosis. The ideal instrument would give information on the mineral content and density of the bone, and on its architecture. It should be able to perform the measurements on the skeletal sites where fractures are more frequent, and it should be minimally invasive, accurate, precise and rapid. Unfortunately, none of the techniques currently utilized fulfills all requirements. In the present review, we focus on the pediatric use of dual\u2013energy X-ray absorptiometry (DXA), quantitative computed tomography (QCT), peripheral QCT (pQCT), and magnetic resonance imaging (MRI), highlighting advantages and limits for their use and providing indications for bone densitometry interpretation and of vertebral fractures diagnosis in pediatric subjects