J Clin Neurol.  2012 Dec;8(4):271-275. 10.3988/jcn.2012.8.4.271.

Mutation Screening of the gamma-Aminobutyric Acid Type-A Receptor Subunit gamma2 Gene in Korean Patients with Childhood Absence Epilepsy

• Kim YO
• Kim MK
• Nam TS
• Jang SY
• Park KW
• Kim EY
• Rho YI
• Woo YJ

• KMID: 2287578
• DOI: http://doi.org/10.3988/jcn.2012.8.4.271

Abstract

BACKGROUND AND PURPOSE
Since the gamma-aminobutyric acid type-A receptor subunit gamma2 gene (GABRG2) mutation was discovered in an Australian family with childhood absence epilepsy (CAE) and febrile convulsions, a few screening studies for the GABRG2 mutation have been conducted in sporadic individuals with CAE from other ethnic groups. The aim of this study was to determine whether or not the previously reported genetic mutations and single-nucleotide polymorphisms (SNPs) of GABRG2 can be reproduced in sporadic Korean individuals with CAE, compared to healthy Korean individuals.
METHODS
Thirty-five children with CAE in Chonnam National University Hospital and healthy controls (n=207) were enrolled, and the medical records of patients with CAE were reviewed. CAE was diagnosed according to the Classification and Terminology of the International League Against Epilepsy. All nine exons of GABRG2 were directly sequenced. In addition, the two SNPs found in our CAE patients were analyzed: C315T in exon 3 (E3) and C588T in exon 5 (E5). The frequencies of the two SNPs in the CAE patients were compared with data from healthy controls (for E3 and E5) and from previously reported Korean population data (only for E3).
RESULTS
No mutation of GABRG2 was found in our CAE patients. In addition, the allele and genotype frequencies of the two polymorphisms did not differ significantly between CAE patients, healthy controls, and the Korean general population (p>0.05).
CONCLUSIONS
Our study of sporadic Korean individuals with CAE found no evidence that GABRG2 contributes to the genetic basis of CAE.

Keyword

GABAA receptor gamma subunit; absence epilepsy; child

MeSH Terms

Alleles
Child
Epilepsy
Epilepsy, Absence
Ethnic Groups
Exons
gamma-Aminobutyric Acid
Genotype
Humans
Mass Screening
Medical Records
Polymorphism, Single Nucleotide
Seizures, Febrile
gamma-Aminobutyric Acid

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