Epilepsy: Genetics

Abstract

At least 40% of all epilepsies have a genetic basis. Some forms of epilepsy have a simple Mendelian mode of inheritance, but these are very rare. The more common forms have a complex genetic background potentially involving several genes. Traditional methodologies for finding disease genes have been relatively successful for Mendelian forms of epilepsy. Although these approaches have been less successful for the common, complex epilepsies, it has still been possible to identify some disease‐associated genes. Most of the genes involved in epilepsy encode ion channel subunits making epilepsy an example of a ‘channelopathy’. The introduction of next generation genetic technologies has increased hope of identifying the specific genetic variants which contribute to individual susceptibility to common and Mendelian epilepsy; and with this comes hope of new deoxyribonucleic acid (DNA)‐based diagnostic techniques and the development of more specific therapies.

Key Concepts:

  • A large proportion of epilepsies have a genetic basis.

  • The majority of genetic epilepsies demonstrate a complex mode of inheritance.

  • Complex inheritance indicates that disease is caused by a combination of genetic changes potentially combined with nongenetic factors.

  • Mode of inheritance can vary between families.

  • Epilepsy is primarily a channelopathy; a disease caused by dysfunction of ion channels.

  • Some genetic changes directly cause disease whereas others alter disease susceptibility.

  • Genetic changes in the same gene can result in different epilepsies.

  • New genetic technologies will facilitate the identification of genetic changes causing both Mendelian and complex epilepsy.

Keywords: epilepsy; neurology; neurogenetics; ion channels; genetic diseases; myoclonin; receptor; Mendelian; complex

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Scheffer IE, Zhang YH, Gecz J and Dibbens L (2010) Genetics of the epilepsies: genetic twists in the channels and other tales. Epilepsia 51(suppl. 1): 33–36.

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Everett, Kate V(Oct 2010) Epilepsy: Genetics. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0005568.pub2]