De novo variants in CNOT9 cause a neurodevelopmental disorder with or without epilepsy.

Purpose: The study aimed to clinically and molecularly characterize the neurodevelopmental disorder associated with heterozygous de novo variants in CNOT9.

Methods: Individuals were clinically examined. Variants were identified using exome or genome sequencing.

Heterozygous variants in PRPF8 are associated with neurodevelopmental disorders.

The pre-mRNA-processing factor 8, encoded by PRPF8, is a scaffolding component of a spliceosome complex involved in the removal of introns from mRNA precursors. Previously, heterozygous pathogenic variants in PRPF8 have been associated with autosomal dominant retinitis pigmentosa. More recently, PRPF8 was suggested as a candidate gene for autism spectrum disorder due to the enrichment of sequence variants in this gene in individuals with neurodevelopmental disorders.

A recurrent, pathogenic variant in disrupts actin filament formation and causes microcephaly and speech delay.

We report seven affected individuals from six families with a recurrent, variant in the gene (c.472C>T [p.Arg158Cys (GenBank: NM_005718.

Clinico-radiological features, molecular spectrum, and identification of prognostic factors in developmental and epileptic encephalopathy due to inosine triphosphate pyrophosphatase (ITPase) deficiency.

Developmental and epileptic encephalopathy 35 (DEE 35) is a severe neurological condition caused by biallelic variants in ITPA, encoding inosine triphosphate pyrophosphatase, an essential enzyme in purine metabolism. We delineate the genotypic and phenotypic spectrum of DEE 35, analyzing possible predictors for adverse clinical outcomes. We investigated a cohort of 28 new patients and reviewed previously described cases, providing a comprehensive characterization of 40 subjects.

Gain-of-function variants in GABRD reveal a novel pathway for neurodevelopmental disorders and epilepsy.

A potential link between GABRD encoding the δ subunit of extrasynaptic GABAA receptors and neurodevelopmental disorders has largely been disregarded due to conflicting conclusions from early studies. However, we identified seven heterozygous missense GABRD variants in 10 patients with neurodevelopmental disorders and generalized epilepsy. One variant occurred in two sibs of healthy parents with presumed somatic mosaicism, another segregated with the disease in three affected family members, and the remaining five occurred de novo in sporadic patients.

Heterozygous Variants in KDM4B Lead to Global Developmental Delay and Neuroanatomical Defects.

KDM4B is a lysine-specific demethylase with a preferential activity on H3K9 tri/di-methylation (H3K9me3/2)-modified histones. H3K9 tri/di-demethylation is an important epigenetic mechanism responsible for silencing of gene expression in animal development and cancer. However, the role of KDM4B on human development is still poorly characterized.

Heterozygous variants that disturb the transcriptional repressor activity of FOXP4 cause a developmental disorder with speech/language delays and multiple congenital abnormalities.

Purpose: Heterozygous pathogenic variants in various FOXP genes cause specific developmental disorders. The phenotype associated with heterozygous variants in FOXP4 has not been previously described.

Methods: We assembled a cohort of eight individuals with heterozygous and mostly de novo variants in FOXP4: seven individuals with six different missense variants and one individual with a frameshift variant.

AMPA receptor GluA2 subunit defects are a cause of neurodevelopmental disorders.

AMPA receptors (AMPARs) are tetrameric ligand-gated channels made up of combinations of GluA1-4 subunits encoded by GRIA1-4 genes. GluA2 has an especially important role because, following post-transcriptional editing at the Q607 site, it renders heteromultimeric AMPARs Ca-impermeable, with a linear relationship between current and trans-membrane voltage. Here, we report heterozygous de novo GRIA2 mutations in 28 unrelated patients with intellectual disability (ID) and neurodevelopmental abnormalities including autism spectrum disorder (ASD), Rett syndrome-like features, and seizures or developmental epileptic encephalopathy (DEE).

Clinical exome sequencing reveals locus heterogeneity and phenotypic variability of cohesinopathies.

Purpose: Defects in the cohesin pathway are associated with cohesinopathies, notably Cornelia de Lange syndrome (CdLS). We aimed to delineate pathogenic variants in known and candidate cohesinopathy genes from a clinical exome perspective.

Methods: We retrospectively studied patients referred for clinical exome sequencing (CES, N = 10,698).

Use of Exome Sequencing for Infants in Intensive Care Units: Ascertainment of Severe Single-Gene Disorders and Effect on Medical Management.

Importance: While congenital malformations and genetic diseases are a leading cause of early infant death, to our knowledge, the contribution of single-gene disorders in this group is undetermined.

Objective: To determine the diagnostic yield and use of clinical exome sequencing in critically ill infants.

Design, Setting, And Participants: Clinical exome sequencing was performed for 278 unrelated infants within the first 100 days of life who were admitted to Texas Children's Hospital in Houston, Texas, during a 5-year period between December 2011 and January 2017.

Biallelic Variants in OTUD6B Cause an Intellectual Disability Syndrome Associated with Seizures and Dysmorphic Features.

Ubiquitination is a posttranslational modification that regulates many cellular processes including protein degradation, intracellular trafficking, cell signaling, and protein-protein interactions. Deubiquitinating enzymes (DUBs), which reverse the process of ubiquitination, are important regulators of the ubiquitin system. OTUD6B encodes a member of the ovarian tumor domain (OTU)-containing subfamily of deubiquitinating enzymes.

THSD1 (Thrombospondin Type 1 Domain Containing Protein 1) Mutation in the Pathogenesis of Intracranial Aneurysm and Subarachnoid Hemorrhage.

Background And Purpose: A ruptured intracranial aneurysm (IA) is the leading cause of a subarachnoid hemorrhage. This study seeks to define a specific gene whose mutation leads to disease.

Methods: More than 500 IA probands and 100 affected families were enrolled and clinically characterized.

Regulated internalization of NMDA receptors drives PKD1-mediated suppression of the activity of residual cell-surface NMDA receptors.

Background: Constitutive and regulated internalization of cell surface proteins has been extensively investigated. The regulated internalization has been characterized as a principal mechanism for removing cell-surface receptors from the plasma membrane, and signaling to downstream targets of receptors. However, so far it is still not known whether the functional properties of remaining (non-internalized) receptor/channels may be regulated by internalization of the same class of receptor/channels.

Introduction to genetic processes in transplantation.

Recent investigations have explored how analyses of genetic DNA from organ donors and recipients may be helpful during organ allocation so as to reduce graft rejection or improve dosing of immunosuppressive medications. This discussion reviews those data and the processes by which genetic coding controls the production of protein that is important in cellular structure and function during donor and recipient care. Changes in gene structure (polymorphisms or mutations) may occur spontaneously or as a result of cell interactions with environmental factors, and may be associated with recognized diseases or, potentially, could reduce or worsen graft rejection.

Sequencing of TGF-beta pathway genes in familial cases of intracranial aneurysm.

Background And Purpose: Familial aggregation of intracranial aneurysms (IA) strongly suggests a genetic contribution to pathogenesis. However, genetic risk factors have yet to be defined. For families affected by aortic aneurysms, specific gene variants have been identified, many affecting the receptors to transforming growth factor-beta (TGF-beta).

Genomewide linkage in a large Caucasian family maps a new locus for intracranial aneurysms to chromosome 13q.

Background And Purpose: Familial aggregation of intracranial aneurysms (IAs) indicates a genetic role in the pathogenesis of this disease. Despite a number of reported susceptibility loci, no disease-causing gene variants have been identified. In this study, we used a parametric genomewide linkage approach to search for new IA susceptibility loci in a large Caucasian family.