Genetic Testing in Epilepsy

David M. Ritter; Katherine Holland

doi:10.1055/s-0040-1719070

Seminars in Neurology, Table of Contents

Semin Neurol 2020; 40(06): 730-738
DOI: 10.1055/s-0040-1719070

Review Article

Genetic Testing in Epilepsy

David M. Ritter

¹Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio

²Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio

,

Katherine Holland

¹Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio

²Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio

› Author Affiliations

Abstract

Because of next-generation sequencing and the discovery of many new causative genes, genetic testing in epilepsy patients has become widespread. Pathologic variants resulting in epilepsy cause a variety of changes that can be broadly classified into syndromic disorders (i.e., chromosomal abnormalities), metabolic disorders, brain malformations, and abnormal cellular signaling. Here, we review the available genetic testing, reasons to pursue genetic testing, common genetic causes of epilepsy, the data behind what patients are found to have genetic epilepsies based on current testing, and discussing these results with patients. We propose an algorithm for testing patients with epilepsy to maximize yield and limit costs based on their phenotype (including electroencephalography and magnetic resonance imaging findings), age of seizure onset, and presence of other neurologic comorbidities. Being able to discern which type of genetic testing to order, using that information to give targeted and cost-effective patient care, and interpreting results accurately will be a crucial skill for the modern neurologist.

Keywords

epilepsy - genetics - genetic testing

Full Text

References

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