No association between SCN9A and monogenic human epilepsy disorders

PLoS Genet. 2020 Nov 20;16(11):e1009161. doi: 10.1371/journal.pgen.1009161. eCollection 2020 Nov.

Abstract

Many studies have demonstrated the clinical utility and importance of epilepsy gene panel testing to confirm the specific aetiology of disease, enable appropriate therapeutic interventions, and inform accurate family counselling. Previously, SCN9A gene variants, in particular a c.1921A>T p.(Asn641Tyr) substitution, have been identified as a likely autosomal dominant cause of febrile seizures/febrile seizures plus and other monogenic seizure phenotypes indistinguishable from those associated with SCN1A, leading to inclusion of SCN9A on epilepsy gene testing panels. Here we present serendipitous findings of genetic studies that identify the SCN9A c.1921A>T p.(Asn641Tyr) variant at high frequency in the Amish community in the absence of such seizure phenotypes. Together with findings in UK Biobank these data refute an association of SCN9A with epilepsy, which has important clinical diagnostic implications.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Amish / genetics
  • Child
  • Child, Preschool
  • Diagnostic Errors / prevention & control*
  • Epilepsy / diagnosis*
  • Epilepsy / genetics
  • Exome Sequencing
  • Female
  • Follow-Up Studies
  • Gene Frequency
  • Genetic Predisposition to Disease
  • Genetic Testing / methods*
  • Heterozygote
  • Humans
  • Infant
  • Male
  • Mutation
  • NAV1.7 Voltage-Gated Sodium Channel / genetics*
  • Pedigree
  • Polymorphism, Single Nucleotide
  • Wisconsin

Substances

  • NAV1.7 Voltage-Gated Sodium Channel
  • SCN9A protein, human