Significant correlation of the SCN1A mutations and severe myoclonic epilepsy in infancy.
To investigate the possible correlation between genotype and phenotype of epilepsy, we analyzed the voltage-gated sodium channel alpha1-subunit (SCN1A) gene, beta1-subunit (SCN1B) gene, and gamma-aminobutyric acid(A) receptor gamma2-subunit (GABRG2) gene in DNAs from peripheral blood cells of 29 patients with severe myoclonic epilepsy in infancy (SME) and 11 patients with other types of epilepsy. Mutations of the SCN1A gene were detected in 24 of the 29 patients (82.7%) with SME, although none with other types of epilepsy. The mutations included deletion, insertion, missense, and nonsense mutations. We could not find any mutations of the SCN1B and GABRG2 genes in all patients. Our data suggested that the SCN1A mutations were significantly correlated with SME (p<.0001). As we could not find SCN1A mutations in their parents, one of critical causes of SME may be de novo mutation of the SCN1A gene occurred in the course of meiosis in the parents.
Ohmori
Iori
I
Department of Child Neurology, Graduate School of Medicine and Dentistry, Okayama University, Shikata-cho 2-5-1, Okayama-shi, Okayama 700-8558, Japan.
Ouchida
Mamoru
M
Ohtsuka
Yoko
Y
Oka
Eiji
E
Shimizu
Kenji
K
D000595:Amino Acid Sequence; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D004831:Epilepsies, Myoclonic / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D062550:NAV1.1 Voltage-Gated Sodium Channel; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics*; D010641:Phenotype; D017434:Protein Structure, Tertiary; D018079:Receptors, GABA / Q000235:genetics; D016415:Sequence Alignment; D015222:Sodium Channels / Q000737:chemistry / Q000235:genetics*
D062550:NAV1.1 Voltage-Gated Sodium Channel; D009419:Nerve Tissue Proteins; D018079:Receptors, GABA; C568242:SCN1A protein, human; D015222:Sodium Channels