De novo protein-coding gene variants in developmental stuttering.

Developmental stuttering is a common childhood condition characterized by disfluencies in speech, such as blocks, prolongations, and repetitions. While most children who stutter do so only transiently, there are some for whom stuttering persists into adulthood. Rare-variant screens in families including multiple relatives with persistent stuttering have so far identified six genes carrying putative pathogenic variants hypothesized to act in a monogenic fashion.

Expanding the Allelic and Clinical Heterogeneity of Movement Disorders Linked to Defects of Mitochondrial Adenosine Triphosphate Synthase.

Background: Defects of mitochondrial ATP synthase (ATPase) represent an emerging, yet incompletely understood group of neurodevelopmental diseases with abnormal movements.

Objective: The aim of this study was to redefine the phenotypic and mutational spectrum of movement disorders linked to the ATPase subunit-encoding genes ATP5F1A and ATP5F1B.

Methods: We recruited regionally distant patients who had been genome or exome sequenced.

Combined genomics and proteomics unveils elusive variants and vast aetiologic heterogeneity in dystonia.

Dystonia is a rare disease trait for which large-scale genomic investigations are still underrepresented. Genetic heterogeneity among patients with unexplained dystonia warrants interrogation of entire genome sequences, but this has not yet been systematically evaluated. To significantly enhance our understanding of the genetic contribution to dystonia, we (re)analysed 2874 whole-exome sequencing (WES), 564 whole-genome sequencing (WGS), as well as 80 fibroblast-derived proteomics datasets, representing the output of high-throughput analyses in 1990 patients and 973 unaffected relatives from 1877 families.

Genetic intersection between dystonia and neurodevelopmental disorders: Insights from genomic sequencing.

Animal and human brain-imaging studies have suggested a role for neurodevelopmental abnormalities in the pathophysiology of dystonia. Variants in neurodevelopmental genes have also been sporadically implicated, although no systematic investigation has been undertaken before the more widespread availability of genome-wide sequencing techniques. Here, we review findings from recent whole-exome and whole-genome sequencing approaches in individuals with dystonic conditions, indicating that more than 50% of molecularly diagnosed cases may have variants in neurodevelopmental disorder-associated genes.

Dystonia as a prominent presenting feature in developmental and epileptic encephalopathies: A case series.

Introduction: Although there has been increasing recognition of the occurrence of non-epileptic involuntary movements in developmental and epileptic encephalopathies (DEEs), the spectrum of dystonic presentations associated with these conditions remains poorly described. We sought to expand the catalogue of dystonia-predominant phenotypes in monogenic DEEs, building on the recently introduced concept of an epilepsy-movement disorder spectrum.

Methods: Cases were identified from a whole-exome-sequenced cohort of 45 pediatric index patients with complex dystonia (67% sequenced as parent-child trios).

Myoclonic dystonia phenotype related to a novel calmodulin-binding transcription activator 1 sequence variant.

Intragenic rearrangements and sequence variants in the calmodulin-binding transcription activator 1 gene (CAMTA1) can result in a spectrum of clinical presentations, most notably congenital ataxia with or without intellectual disability. We describe for the first time a myoclonic dystonia-predominant phenotype associated with a novel CAMTA1 sequence variant. Furthermore, by identifying an additional, recurrent CAMTA1 sequence variant in an individual with a more typical neurodevelopmental disease manifestation, we contribute to the elucidation of phenotypic variability associated with CAMTA1 gene mutations.

Variant recurrence confirms the existence of a FBXO31-related spastic-dystonic cerebral palsy syndrome.

The role of genetics in the causation of cerebral palsy has become the focus of many studies aiming to unravel the heterogeneous etiology behind this frequent neurodevelopmental disorder. A recent paper reported two unrelated children with a clinical diagnosis of cerebral palsy, who carried the same de novo c.1000G > A (p.