Burden re-analysis of neurodevelopmental disorder cohorts for prioritization of candidate genes.

This study aimed to uncover novel genes associated with neurodevelopmental disorders (NDD) by leveraging recent large-scale de novo burden analysis studies to enhance a virtual gene panel used in a diagnostic setting. We re-analyzed historical trio-exome sequencing data from 745 individuals with NDD according to the most recent diagnostic standards, resulting in a cohort of 567 unsolved individuals. Next, we designed a virtual gene panel containing candidate genes from three large de novo burden analysis studies in NDD and prioritized candidate genes by stringent filtering for ultra-rare de novo variants with high pathogenicity scores.

Expanding the phenotype of Harel-Yoon syndrome: A case report suggesting a genotype/phenotype correlation.

Harel-Yoon syndrome (HAYOS) is a unique neurodevelopmental genetic disorder characterized by hypotonia, spasticity, intellectual disability, hypertrophic cardiomyopathy, and global developmental delay. It primarily results from mutations in the ATAD3A gene, pivotal for mitochondrial function. This report presents a 5-year-old girl with HAYOS harboring a de novo heterozygous variant c.

De novo missense variants in ZBTB47 are associated with developmental delays, hypotonia, seizures, gait abnormalities, and variable movement abnormalities.

The collection of known genetic etiologies of neurodevelopmental disorders continues to increase, including several syndromes associated with defects in zinc finger protein transcription factors (ZNFs) that vary in clinical severity from mild learning disabilities and developmental delay to refractory seizures and severe autism spectrum disorder. Here we describe a new neurodevelopmental disorder associated with variants in ZBTB47 (also known as ZNF651), which encodes zinc finger and BTB domain-containing protein 47. Exome sequencing (ES) was performed for five unrelated patients with neurodevelopmental disorders.

Novel Phenotype in Unbalanced 7;9 Translocation with Critical Incidental Finding.

This case discusses a now 13-year-old boy who underwent chromosome analysis and fluorescence in situ hybridization (FISH) for subtelomeric rearrangements due to dysmorphic features at birth. This testing revealed a diagnosis of an unbalanced 7;9 translocation resulting in monosomy for 7q34-qter and trisomy for 9pter-p21, which resulted in a very complex medical course. At the age of 12, due to persistent complex neurodevelopmental concerns, the patient was referred by neurology for whole-exome sequencing.

Expanding the genotypic and phenotypic spectrum in a diverse cohort of 104 individuals with Wiedemann-Steiner syndrome.

Wiedemann-Steiner syndrome (WSS) is an autosomal dominant disorder caused by monoallelic variants in KMT2A and characterized by intellectual disability and hypertrichosis. We performed a retrospective, multicenter, observational study of 104 individuals with WSS from five continents to characterize the clinical and molecular spectrum of WSS in diverse populations, to identify physical features that may be more prevalent in White versus Black Indigenous People of Color individuals, to delineate genotype-phenotype correlations, to define developmental milestones, to describe the syndrome through adulthood, and to examine clinicians' differential diagnoses. Sixty-nine of the 82 variants (84%) observed in the study were not previously reported in the literature.

Case report: Novel phenotype in central 22q11.2 deletion syndrome.

Deletions within 22q11.2 are one of the most common microdeletions studied. We report a case of central 22q11.

A case series of a mother and two daughters with a gene deletion demonstrating variable expressivity and incomplete penetrance.

This case series and review of the literature support that patients with pathogenic variants of the GLI2 gene demonstrate an autosomal dominant inheritance pattern, variable expressivity, and incomplete penetrance.

Damaging de novo missense variants in EEF1A2 lead to a developmental and degenerative epileptic-dyskinetic encephalopathy.

Heterozygous de novo variants in the eukaryotic elongation factor EEF1A2 have previously been described in association with intellectual disability and epilepsy but never functionally validated. Here we report 14 new individuals with heterozygous EEF1A2 variants. We functionally validate multiple variants as protein-damaging using heterologous expression and complementation analysis.

GATAD2B-associated neurodevelopmental disorder (GAND): clinical and molecular insights into a NuRD-related disorder.

Purpose: Determination of genotypic/phenotypic features of GATAD2B-associated neurodevelopmental disorder (GAND).

Methods: Fifty GAND subjects were evaluated to determine consistent genotypic/phenotypic features. Immunoprecipitation assays utilizing in vitro transcription-translation products were used to evaluate GATAD2B missense variants' ability to interact with binding partners within the nucleosome remodeling and deacetylase (NuRD) complex.

Defining the clinical phenotype of Saul-Wilson syndrome.

Purpose: Four patients with Saul-Wilson syndrome were reported between 1982 and 1994, but no additional individuals were described until 2018, when the molecular etiology of the disease was elucidated. Hence, the clinical phenotype of the disease remains poorly defined. We address this shortcoming by providing a detailed characterization of its phenotype.

De novo and inherited variants in ZNF292 underlie a neurodevelopmental disorder with features of autism spectrum disorder.

Purpose: Intellectual disability (ID) and autism spectrum disorder (ASD) are genetically heterogeneous neurodevelopmental disorders. We sought to delineate the clinical, molecular, and neuroimaging spectrum of a novel neurodevelopmental disorder caused by variants in the zinc finger protein 292 gene (ZNF292).

Methods: We ascertained a cohort of 28 families with ID due to putatively pathogenic ZNF292 variants that were identified via targeted and exome sequencing.

NK cell defects in X-linked pigmentary reticulate disorder.

X-linked reticulate pigmentary disorder (XLPDR, Mendelian Inheritance in Man #301220) is a rare syndrome characterized by recurrent infections and sterile multiorgan inflammation. The syndrome is caused by an intronic mutation in POLA1, the gene encoding the catalytic subunit of DNA polymerase-α (Pol-α), which is responsible for Okazaki fragment synthesis during DNA replication. Reduced POLA1 expression in this condition triggers spontaneous type I interferon expression, which can be linked to the autoinflammatory manifestations of the disease.

Unexpected Finding of Idiopathic REM Sleep Behavior Disorder in a Young Healthy Male With Snoring: A Case Report.

None: Idiopathic rapid eye movement sleep behavior disorder is characterized by vocalizations and complex motor behaviors during sleep. We report a case of a 44-year-old male with a 20-year history of dream enactment behavior that was incidentally captured on a polysomnogram during an evaluation for obstructive sleep apnea. Genetic testing found the patient had a homozygous deletion for one of the five tandem repeats in exon 18 of the PER3 gene.

Defective DNA Polymerase α-Primase Leads to X-Linked Intellectual Disability Associated with Severe Growth Retardation, Microcephaly, and Hypogonadism.

Replicating the human genome efficiently and accurately is a daunting challenge involving the duplication of upward of three billion base pairs. At the core of the complex machinery that achieves this task are three members of the B family of DNA polymerases: DNA polymerases α, δ, and ε. Collectively these multimeric polymerases ensure DNA replication proceeds at optimal rates approaching 2 × 10 nucleotides/min with an error rate of less than one per million nucleotides polymerized.

Youngest presenting patient with dystonia 24 and review of the literature.

Dystonia 24 was first reported in 2000 as an autosomal dominant cause of dystonia caused by variants in the gene. Although many adults have been described with dystonia 24, since 2014, an increasing number of children have also been reported. Dystonia 24 should also be considered in the differential of a child with unexplained dystonia.

Fashionably Late: A Case of Delayed Cutaneous Manifestations in Juvenile Dermatomyositis.

Juvenile dermatomyositis (JDM) is a rare, but well recognized multi-systemic inflammatory myopathy in children defined by proximal muscle weakness and distinctive skin lesions, that if recognized and treated early result in decreased morbidity and mortality. The 1975 criteria established by Bohan and Peter center around the propensity for early development of heliotrope and Gottron's lesions in combination with specific laboratory abnormalities, and are still the leading diagnostic tool. The following case demonstrates a toddler with an atypical presentation of JDM in which delayed dermatologic manifestations hindered initial diagnosis.

A Recurrent De Novo Heterozygous COG4 Substitution Leads to Saul-Wilson Syndrome, Disrupted Vesicular Trafficking, and Altered Proteoglycan Glycosylation.

The conserved oligomeric Golgi (COG) complex is involved in intracellular vesicular transport, and is composed of eight subunits distributed in two lobes, lobe A (COG1-4) and lobe B (COG5-8). We describe fourteen individuals with Saul-Wilson syndrome, a rare form of primordial dwarfism with characteristic facial and radiographic features. All affected subjects harbored heterozygous de novo variants in COG4, giving rise to the same recurrent amino acid substitution (p.

Tetraploid-diploid mosaicism in a patient with pigmentary anomalies of hair and skin: a new dermatologic feature.

Tetraploid-diploid mosaicism in humans is exceedingly rare. We present an 11-year-old boy with tetraploid-diploid mosaicism and coexistent hair hypopigmentation with skin hypo- and hyperpigmentation. This case expands the current literature as we are not aware of previous documentation of this unique combination of pigmentary anomalies.

Rare presentation of 6q16.3 microdeletion syndrome with severe upper limb reduction defects and duodenal atresia.

We present a patient with a 17.31 MB interstitial deletion of 6q16.3-6q22.