New Genes for Focal Epilepsies with Speech and Language Disorders

  • Samantha J. Turner
  • Angela T. Morgan
  • Eliane Roulet Perez
  • Ingrid E. Scheffer
Genetics (V Bonifati, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Genetics

Abstract

The last 2 years have seen exciting advances in the genetics of Landau-Kleffner syndrome and related disorders, encompassed within the epilepsy-aphasia spectrum (EAS). The striking finding of mutations in the N-methyl-d-aspartate (NMDA) receptor subunit gene GRIN2A as the first monogenic cause in up to 20 % of patients with EAS suggests that excitatory glutamate receptors play a key role in these disorders. Patients with GRIN2A mutations have a recognizable speech and language phenotype that may assist with diagnosis. Other molecules involved in RNA binding and cell adhesion have been implicated in EAS; copy number variations are also found. The emerging picture highlights the overlap between the genetic determinants of EAS with speech and language disorders, intellectual disability, autism spectrum disorders and more complex developmental phenotypes.

Keywords

Epilepsy-aphasia spectrum Speech Language Gene Landau-Kleffner syndrome Epileptic encephalopathy with continuous spike-wave during sleep Benign childhood epilepsy with centro-temporal spikes GRIN2A RBFOX genes Copy number variants Dysarthria Speech dyspraxia Oromotor dyspraxia Continuous spike-wave in slow sleep Rolandic Atypical benign partial epilepsy Autosomal dominant rolandic epilepsy with speech dyspraxia 

References

Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Samantha J. Turner
    • 1
    • 2
    • 6
  • Angela T. Morgan
    • 1
    • 2
    • 3
  • Eliane Roulet Perez
    • 4
  • Ingrid E. Scheffer
    • 1
    • 5
    • 6
  1. 1.Department of Paediatrics, The University of MelbourneThe Royal Children’s HospitalParkvilleAustralia
  2. 2.Language and Literacy GroupMurdoch Childrens Research InstituteParkvilleAustralia
  3. 3.Speech Pathology DepartmentThe Royal Children’s HospitalParkvilleAustralia
  4. 4.Paediatric Neurology and Neurorehabilitation UnitHospitalier Universitaire VaudoisLausanneSwitzerland
  5. 5.Florey Institute of Neuroscience and Mental HealthMelbourneAustralia
  6. 6.Epilepsy Research Centre, Department of MedicineUniversity of Melbourne, Austin HealthMelbourneAustralia

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