Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
2007-11-5
pubmed:abstractText
The mammalian genome contains four voltage-gated sodium channel genes that are primarily expressed in the central nervous system: SCN1A, SCN2A, SCN3A and SCN8A. Mutations in SCN1A and SCN2A are responsible for several dominant idiopathic epilepsy disorders, including generalized epilepsy with febrile seizures plus (GEFS+) and severe myoclonic epilepsy of infancy (SMEI). Mutations in SCN8A are associated with cognitive deficits and neuropsychiatric illness in humans and movement disorders in mice; however, a role for SCN8A (Na(v)1.6) in epilepsy has not been investigated. To determine the relationship between Na(v)1.6 dysfunction and seizure susceptibility, we examined the thresholds of two Scn8a mouse mutants, Scn8a(med) and Scn8a(med-jo), to flurothyl- and kainic acid (KA)-induced seizures. Both mutants were more seizure resistant than wild-type littermates, suggesting that altered Na(v)1.6 function reduces neuronal excitability. To determine whether impaired Na(v)1.6 function could ameliorate seizure severity in a mouse model of SMEI, we generated Scn1a(+/-); Scn8a(med-jo/+) double heterozygous mice. Unlike Scn1a(+/-) mice that are more susceptible to flurothyl-induced seizures, Scn1a(+/-); Scn8a(med-jo/+) mice displayed thresholds that were comparable to wild-type littermates. The Scn8a(med-jo) allele was also able to rescue the premature lethality of Scn1a(+/-) mice and extend the lifespan of Scn1a(-/-) mutants. These results demonstrate that genetic interactions can alter seizure severity and support the hypothesis that genetic modifiers contribute to the clinical variability observed in SMEI and GEFS+.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0964-6906
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2892-9
pubmed:meshHeading
pubmed-meshheading:17881658-Animals, pubmed-meshheading:17881658-Base Sequence, pubmed-meshheading:17881658-DNA Primers, pubmed-meshheading:17881658-Disease Models, Animal, pubmed-meshheading:17881658-Epilepsies, Myoclonic, pubmed-meshheading:17881658-Female, pubmed-meshheading:17881658-Genes, Lethal, pubmed-meshheading:17881658-Heterozygote, pubmed-meshheading:17881658-Homozygote, pubmed-meshheading:17881658-Humans, pubmed-meshheading:17881658-Infant, pubmed-meshheading:17881658-Male, pubmed-meshheading:17881658-Mice, pubmed-meshheading:17881658-Mice, Knockout, pubmed-meshheading:17881658-Mice, Mutant Strains, pubmed-meshheading:17881658-Mutation, pubmed-meshheading:17881658-Nerve Tissue Proteins, pubmed-meshheading:17881658-Phenotype, pubmed-meshheading:17881658-Seizures, pubmed-meshheading:17881658-Sodium Channels
pubmed:year
2007
pubmed:articleTitle
The voltage-gated sodium channel Scn8a is a genetic modifier of severe myoclonic epilepsy of infancy.
pubmed:affiliation
Department of Human Genetics, Emory University, Atlanta, GA 30322, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural