The UBE3A-ATS antisense oligonucleotide rugonersen in children with Angelman syndrome: a phase 1 trial.

Angelman syndrome (AS) is a severe genetic neurodevelopmental disorder with no disease-modifying treatments. AS is caused by deletion or mutation of the neuronally imprinted gene encoding the ubiquitin-protein ligase E3A (UBE3A). Rugonersen (RO7248824) is an antisense oligonucleotide that reinstates UBE3A by derepressing the silenced paternal allele.

Detection of Clinically Relevant Monogenic Copy-Number Variants by a Comprehensive Genome-Wide Microarray with Exonic Coverage.

Background: Disease-causing copy-number variants (CNVs) often encompass contiguous genes and can be detected using chromosomal microarray analysis (CMA). Conversely, CNVs affecting single disease-causing genes have historically been challenging to detect due to their small sizes.

Methods: A custom comprehensive CMA (Baylor College of Medicine - BCM v11.

Sustained growth-promoting effects of vosoritide in children with achondroplasia from an ongoing phase 3 extension study.

Background: Vosoritide is a C-type natriuretic peptide analog that addresses an underlying pathway causing reduced bone growth in achondroplasia. Understanding the vosoritide treatment effect requires evaluation over an extended duration and comparison with outcomes in untreated children.

Methods: After completing ≥6 months of a baseline observational growth study and 52 weeks in a double-blind, placebo-controlled study (ClinicalTrials.

Neurodevelopmental Disorder Caused by Deletion of , a lncRNA Gene.

encodes a human long noncoding RNA (lncRNA) adjacent to , a coding gene in which de novo loss-of-function variants cause developmental and epileptic encephalopathy. Here, we report our findings in three unrelated children with a syndromic, early-onset neurodevelopmental disorder, each of whom had a de novo deletion in the locus. The children had severe encephalopathy, shared facial dysmorphisms, cortical atrophy, and cerebral hypomyelination - a phenotype that is distinct from the phenotypes of patients with haploinsufficiency.

Recurrent carotid paragangliomas in a syndromic patient with a heterozygous missense variant in DNA Methyltransferase 3 Alpha.

We report a 40-year-old African American female with a novel variant in exon 8 of DNA methyltransferase 3 alpha (DNMT3A), (NM_022552.4: c.905G>C, p.

Developmental milestones and daily living skills in individuals with Angelman syndrome.

Background: Angelman syndrome (AS) is a neurodevelopmental disorder associated with severe global developmental delay. However, the ages at which different developmental skills are achieved in these individuals remain unclear. We seek to determine the probability and the age of acquisition of specific developmental milestones and daily living skills in individuals with AS across the different molecular subtypes, viz.

Development of a Weight-Band Dosing Approach for Vosoritide in Children with Achondroplasia Using a Population Pharmacokinetic Model.

Background And Objective: Vosoritide is a recently approved therapy for achondroplasia, the most common form of disproportionate short stature, that has been shown to be well tolerated and effective in increasing linear growth. This study aimed to develop a population pharmacokinetic (PPK) model to characterize pharmacokinetics (PK) of vosoritide and establish a weight-band dosing regimen.

Methods: A PPK model was developed using data from five clinical trials in children with achondroplasia (aged 0.

The clinical utility and diagnostic implementation of human subject cell transdifferentiation followed by RNA sequencing.

RNA sequencing (RNA-seq) has recently been used in translational research settings to facilitate diagnoses of Mendelian disorders. A significant obstacle for clinical laboratories in adopting RNA-seq is the low or absent expression of a significant number of disease-associated genes/transcripts in clinically accessible samples. As this is especially problematic in neurological diseases, we developed a clinical diagnostic approach that enhanced the detection and evaluation of tissue-specific genes/transcripts through fibroblast-to-neuron cell transdifferentiation.

Improving access to exome sequencing in a medically underserved population through the Texome Project.

Purpose: Genomic medicine can end diagnostic odysseys for patients with complex phenotypes; however, limitations in insurance coverage and other systemic barriers preclude individuals from accessing comprehensive genetics evaluation and testing.

Methods: The Texome Project is a 4-year study that reduces barriers to genomic testing for individuals from underserved and underrepresented populations. Participants with undiagnosed, rare diseases who have financial barriers to obtaining exome sequencing (ES) clinically are enrolled in the Texome Project.

A syndromic neurodevelopmental disorder caused by rare variants in PPFIA3.

PPFIA3 encodes the protein-tyrosine phosphatase, receptor-type, F-polypeptide-interacting-protein-alpha-3 (PPFIA3), which is a member of the LAR-protein-tyrosine phosphatase-interacting-protein (liprin) family involved in synapse formation and function, synaptic vesicle transport, and presynaptic active zone assembly. The protein structure and function are evolutionarily well conserved, but human diseases related to PPFIA3 dysfunction are not yet reported in OMIM. Here, we report 20 individuals with rare PPFIA3 variants (19 heterozygous and 1 compound heterozygous) presenting with developmental delay, intellectual disability, hypotonia, dysmorphisms, microcephaly or macrocephaly, autistic features, and epilepsy with reduced penetrance.

Vosoritide therapy in children with achondroplasia aged 3-59 months: a multinational, randomised, double-blind, placebo-controlled, phase 2 trial.

Background: Vosoritide is a recombinant C-type natriuretic peptide analogue that increases annualised growth velocity in children with achondroplasia aged 5-18 years. We aimed to assess the safety and efficacy of vosoritide in infants and children younger than 5 years.

Methods: This double-blind, randomised, placebo-controlled, phase 2 trial was done in 16 hospitals across Australia, Japan, the UK, and the USA.

Once-weekly TransCon CNP (navepegritide) in children with achondroplasia (ACcomplisH): a phase 2, multicentre, randomised, double-blind, placebo-controlled, dose-escalation trial.

Background: TransCon CNP (navepegritide) is an investigational prodrug of C-type natriuretic peptide (CNP) designed to allow for continuous CNP exposure with once-weekly dosing. This 52-week phase 2 (ACcomplisH) trial assessed the safety and efficacy of TransCon CNP in children with achondroplasia.

Methods: ACcomplisH is a global, randomised, double-blind, placebo-controlled, dose-escalation trial.

Enabling endpoint development for interventional clinical trials in individuals with Angelman syndrome: a prospective, longitudinal, observational clinical study (FREESIAS).

Background: Angelman syndrome (AS) is a rare neurodevelopmental disorder characterized by the absence of a functional UBE3A gene, which causes developmental, behavioral, and medical challenges. While currently untreatable, comprehensive data could help identify appropriate endpoints assessing meaningful improvements in clinical trials. Herein are reported the results from the FREESIAS study assessing the feasibility and utility of in-clinic and at-home measures of key AS symptoms.

Rare variants in cause delayed development, intellectual disability, autism, and epilepsy.

encodes the Protein-Tyrosine Phosphatase, Receptor-Type, F Polypeptide-Interacting Protein Alpha-3 (PPFIA3), which is a member of the LAR protein-tyrosine phosphatase-interacting protein (liprin) family involved in synaptic vesicle transport and presynaptic active zone assembly. The protein structure and function are well conserved in both invertebrates and vertebrates, but human diseases related to PPFIA3 dysfunction are not yet known. Here, we report 14 individuals with rare mono-allelic variants presenting with features including developmental delay, intellectual disability, hypotonia, autism, and epilepsy.

YWHAE loss of function causes a rare neurodevelopmental disease with brain abnormalities in human and mouse.

Purpose: Miller-Dieker syndrome is caused by a multiple gene deletion, including PAFAH1B1 and YWHAE. Although deletion of PAFAH1B1 causes lissencephaly unambiguously, deletion of YWHAE alone has not clearly been linked to a human disorder.

Methods: Cases with YWHAE variants were collected through international data sharing networks.

Growth parameters in children with achondroplasia: A 7-year, prospective, multinational, observational study.

Purpose: This study was undertaken to collect baseline growth parameters in children with achondroplasia who might enroll in interventional trials of vosoritide, and to establish a historical control.

Methods: In this prospective, observational study, participants (≤17 years) underwent a detailed medical history and physical examination and were followed every 3 months until they finished participating in the study by enrolling in an interventional trial or withdrawing.

Results: A total of 363 children were enrolled (28 centers, 8 countries).

Phenotypic and genetic spectrum of ATP6V1A encephalopathy: a disorder of lysosomal homeostasis.

Vacuolar-type H+-ATPase (V-ATPase) is a multimeric complex present in a variety of cellular membranes that acts as an ATP-dependent proton pump and plays a key role in pH homeostasis and intracellular signalling pathways. In humans, 22 autosomal genes encode for a redundant set of subunits allowing the composition of diverse V-ATPase complexes with specific properties and expression. Sixteen subunits have been linked to human disease.