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Genetic Testing of Epileptic Encephalopathies of Infancy: An Approach

Published online by Cambridge University Press:  23 September 2014

Suvasini Sharma  and
Asuri N. Prasad
Suvasini Sharma
Affiliation:
Department of Pediatrics, Lady Hardinge Medical College, New Delhi, India
Asuri N. Prasad*
Affiliation:
Department of Pediatrics, Schulich School of Medicine and Dentistry, Children's Hospital of Western Ontario, London, Ontario, Canada
*
Department of Pediatrics, Schulich School of Medicine and Dentistry, Children's Hospital of Western Ontario, London, Ontario, Canada email: [email protected]
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Abstract:

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The epileptic encephalopathies of infancy are a group of disorders characterized by intractable seizures, persistent abnormality of cortical function documented on EEG, and consequently impaired neuro-developmental outcomes. The etiologies vary and include; structural brain malformations, acquired brain insults, and inborn errors of metabolism in the majority of the affected patients. In a proportion of these cases no obvious etiology is identifiable on investigation. Recent advances in molecular diagnostics have led to the discovery of a number of gene defects that may be causal in many epileptic encephalopathies. Identification of the causative mutation is important for prognostic and genetic counseling, and may also carry treatment implications. The recently described genes include; Cyclin-Dependent Kinase-Like 5 gene (CDKL5), Protocadherin 19 (PCDH19), Sodium channel neuronal type 1a subunit gene (SCN1A), Aristaless-Related Homeobox Gene (ARX), and Syntaxin binding protein 1 gene (STXBP1), amongst others. Distinct electro-clinical syndromes are increasingly being identified amongst patients carrying the various mutations. In this review, we outline the approach to clinical evaluation and genetic testing of epileptic encephalopathies in infancy.

Type
Review Article
Information
Canadian Journal of Neurological Sciences , Volume 40 , Issue 1 , January 2013 , pp. 10 - 16
Copyright
Copyright © The Canadian Journal of Neurological 2013

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