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Neurological Sciences

, Volume 39, Issue 6, pp 1113–1115 | Cite as

Variable epilepsy phenotypes associated with heterozygous mutation in the SCN9A gene: report of two cases

  • Cuiwei Yang
  • Yi Hua
  • Weiqin Zhang
  • Jialu Xu
  • Lu Xu
  • Feng Gao
  • Peifang JiangEmail author
Brief Communication

Abstract

Up to now, SCN9A mutations encoding Nav1.7 have been limited to inherited pain syndromes. A few of pathogenic SCN9A mutations with or without SCN1A mutations have been identified in epileptic patients. Here, we report two heterozygous SCN9A mutations with no SCN1A mutations, which are associated with variable epilepsy phenotypes and explored the possibility of SCN9A contributing to a multifactorial etiology for epilepsy. Our findings suggest that the two SCN9A mutations (c.980G>A chr2:167149868 p.G327E; c.5702_5706del chr2:167055410 p.I1901fs) should be regarded as pathogenic mutations. Two heterozygous mutations of SCN9A are associated with a wide clinical spectrum of seizure phenotypes including simple febrile seizures, afebrile seizures, generalized tonic-clonic seizure, myoclonic or tonic seizures, and focal clonic seizures. Patients with deletion mutations tend to be associated with more severe seizure type than missense mutations.

Keywords

SCN9A Heterozygous mutation Epilepsy Febrile seizures 

Notes

Acknowledgements

We would like to thank the patient’s parents for providing written informed consent for the publication of the manuscript and any accompanying images.

Funding information

This project was funded by grants from National Natural Science Foundation of China (81201511, 81671287) and Zhejiang Provincial Natural Science Foundation of China (LY15H090006).

Compliance with ethical standards

Conflict of interest

The authors declare that there are no conflicts of interest.

References

  1. 1.
    Meisler MH, O’Brien JE, Sharkey LM (2010) Sodium channel gene family: epilepsy mutations, gene interactions and modifier effects. J Physiol 588:1841–1848CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    Brunklaus A, Ellis R, Reavey E, Forbes GH, Zuberi SM (2012) Prognostic, clinical and demographic features in SCN1A mutation-positive Dravet syndrome. Brain 135:2329–2336CrossRefPubMedGoogle Scholar
  3. 3.
    Estacion M, Harty TP, Choi JS, Tyrrell L, Dib-Hajj SD, Waxman SG (2009) A sodium channel gene SCN9A polymorphism that increases nociceptor excitability. Ann Neurol 66:862–866CrossRefPubMedGoogle Scholar
  4. 4.
    Mulley JC, Hodgson B, McMahon JM et al (2013) Role of the sodium channel SCN9A in genetic epilepsy with febrile seizures plus and Dravet syndrome. Epilepsia 54:e122–e126CrossRefPubMedGoogle Scholar
  5. 5.
    Singh NA, Pappas C, Dahle EJ, Claes LRF, Pruess TH, de Jonghe P, Thompson J, Dixon M, Gurnett C, Peiffer A, White HS, Filloux F, Leppert MF (2009) A role of SCN9A in human epilepsies, as a cause of febrile seizures and as a potential modifier of Dravet syndrome. PLoS Genet 5:e1000649CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Springer-Verlag Italia S.r.l., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Neurology, Children’s Hospital, School of MedicineZhejiang UniversityHangzhouPeople’s Republic of China

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