SCN8A heterozygous variants are associated with anoxic-epileptic seizures.
SCN8A
AES
anoxic-epileptic seizures
childhood epilepsy
sodium channel blockers
Journal
American journal of medical genetics. Part A
ISSN: 1552-4833
Titre abrégé: Am J Med Genet A
Pays: United States
ID NLM: 101235741
Informations de publication
Date de publication:
05 2020
05 2020
Historique:
received:
28
02
2019
revised:
07
11
2019
accepted:
06
01
2020
pubmed:
11
2
2020
medline:
13
1
2021
entrez:
11
2
2020
Statut:
ppublish
Résumé
Anoxic-epileptic seizures (AES) are rare outcomes of common childhood reflex anoxic syncope that trigger a true epileptic seizure. The term AES was coined by Stephenson in 1983, to differentiate these events from convulsive syncopes and the more common reflex anoxic syncopes. A genetic susceptibility for AES has been postulated; but, its molecular basis has up to now been elusive. We report here two illustrative cases and show the association of de novo SCN8A variants and AES. One of them had focal or generalized seizures and autonomic symptoms triggered by orthostatism; the second had breath-holding spells triggered by pain or exercise leading to tonic-clonic seizures; both had repeatedly normal EEGs and a family history of reflex syncope. The data of three additional AES patients further suggest, for the first time, a link between SCN8A pathogenic variants and AES. The neurodevelopment of four patients was abnormal. Four of the five SCN8A mutations observed here were previously described in patients with seizure disorders. Seizures responded particularly well to sodium channel blockers. Our observation enriches the spectrum of seizures linked with SCN8A pathogenic variants.
Identifiants
pubmed: 32040247
doi: 10.1002/ajmg.a.61513
doi:
Substances chimiques
NAV1.6 Voltage-Gated Sodium Channel
0
SCN8A protein, human
0
Types de publication
Case Reports
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
1209-1216Informations de copyright
© 2020 Wiley Periodicals, Inc.
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