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BMC Neurology
Published in: BMC Neurology 1/2024

Open Access 01-12-2024 | Epilepsy | Case Report

Expanding the genotype-phenotype spectrum in SCN8A-related disorders

Authors: Malavika Hebbar, Nawaf Al-Taweel, Inderpal Gill, Cyrus Boelman, Richard A. Dean, Samuel J. Goodchild, Janette Mezeyova, Noah Gregory Shuart, J. P. Johnson Jr., James Lee, Aspasia Michoulas, Linda L. Huh, Linlea Armstrong, Mary B. Connolly, Michelle K. Demos

Published in: BMC Neurology | Issue 1/2024

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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.
Appendix
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Metadata
Title
Expanding the genotype-phenotype spectrum in SCN8A-related disorders
Authors
Malavika Hebbar
Nawaf Al-Taweel
Inderpal Gill
Cyrus Boelman
Richard A. Dean
Samuel J. Goodchild
Janette Mezeyova
Noah Gregory Shuart
J. P. Johnson Jr.
James Lee
Aspasia Michoulas
Linda L. Huh
Linlea Armstrong
Mary B. Connolly
Michelle K. Demos
Publication date
01-12-2024
Publisher
BioMed Central
Published in
BMC Neurology / Issue 1/2024
Electronic ISSN: 1471-2377
DOI
https://doi.org/10.1186/s12883-023-03478-y

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