Expanding the genotype-phenotype spectrum in SCN8A-related disorders.
Ontology highlight
ABSTRACT: Background
SCN8A-related disorders are a group of variable conditions caused by pathogenic variations in SCN8A. Online Mendelian Inheritance in Man (OMIM) terms them as developmental and epileptic encephalopathy 13, benign familial infantile seizures 5 or cognitive impairment with or without cerebellar ataxia.Methods
In this study, we describe clinical and genetic results on eight individuals from six families with SCN8A pathogenic variants identified via exome sequencing.Results
Clinical findings ranged from normal development with well-controlled epilepsy to significant developmental delay with treatment-resistant epilepsy. Three novel and three reported variants were observed in SCN8A. Electrophysiological analysis in transfected cells revealed a loss-of-function variant in Patient 4.Conclusions
This work expands the clinical and genotypic spectrum of SCN8A-related disorders and provides electrophysiological results on a novel loss-of-function SCN8A variant.
SUBMITTER: Hebbar M
PROVIDER: S-EPMC10792783 | biostudies-literature | 2024 Jan
REPOSITORIES: biostudies-literature
Publications
Expanding the genotype-phenotype spectrum in SCN8A-related disorders.
Hebbar Malavika M Al-Taweel Nawaf N Gill Inderpal I Boelman Cyrus C Dean Richard A RA Goodchild Samuel J SJ Mezeyova Janette J Shuart Noah Gregory NG Johnson J P JP Lee James J Michoulas Aspasia A Huh Linda L LL Armstrong Linlea L Connolly Mary B MB Demos Michelle K MK
BMC neurology 20240117 1
<h4>Background</h4>SCN8A-related disorders are a group of variable conditions caused by pathogenic variations in SCN8A. Online Mendelian Inheritance in Man (OMIM) terms them as developmental and epileptic encephalopathy 13, benign familial infantile seizures 5 or cognitive impairment with or without cerebellar ataxia.<h4>Methods</h4>In this study, we describe clinical and genetic results on eight individuals from six families with SCN8A pathogenic variants identified via exome sequencing.<h4>Res ...[more]
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Project description:Background SCN8A -related disorders are a group of variable conditions caused by pathogenic variations in SCN8A. Online Mendelian Inheritance in Man (OMIM) terms them as developmental and epileptic encephalopathy 13, benign familial infantile seizures 5 or cognitive impairment with or without cerebellar ataxia. Methods In this study, we describe clinical and genetic results on eight individuals from six families with SCN8A pathogenic variants identified via exome sequencing. Results Clinical findings ranged from normal development with well-controlled epilepsy to significant developmental delay with treatment-resistant epilepsy. Three novel and three reported variants were observed in SCN8A . Electrophysiological analysis in transfected cells revealed a loss-of-function variant in Patient 4. Conclusions This work expands the clinical and genotypic spectrum of SCN8A -related disorders and provides electrophysiological results on a novel loss-of-function SCN8A variant.
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