STRAIN INFORMATION


Family Identifier
SZT1
Synonym(s)
C57BL/J-Szt1/FrkJ; JR#4587
Synopsis
Heterozygotes have low threshold for electroconvulsive and PTZ-induced seizures; homozygotes show perinatal lethality.
Gene Symbol
Szt1 (View MGI Record)
Gene
Seizure threshold1
Allele Symbol
Szt1 (View MGI Record)
Allele
Seizure threshold1
Abnormal Assay(s)
Assay: Electroconvulsive threshold (ECT)

   Domain(s): Epilepsy
Phenotype Description
Mice heterozygous for the Szt1 mutation are characterized through low thresholds for minimal electroconvulsive and PTZ induced tonic-clonic seizures. Although these mice do not exhibit spontaneous seizures and have a normal EEG, they might be useful for studying neurobiological mechanisms related to epilepsy. The mutants are smaller than wild-type littermates, but are generally viable and fertile. Homozygous Szt1 mice die approximately 12hrs after birth of apparent pulmonary atelectasis. While Szt1 mutants were initially discovered following ENU induced mutagenesis, subsequent examination of G0 founder DNA suggested that Szt1 represents a spontaneous, not an ENU induced mutation. The Szt1 mutation represents a genomic deletion of about 300 kb of mouse chromosome 2. The deletion involves several genes including those encoding the potassium channel, Kcnq2, and the nicotinic acetylcholine receptor subunit, Chrna4. Mutations in the respective human homologues are associated with human familial epilepsy.
Pathology Report
Mapping with yellow fluorescent protein showed an approximately 40% reduction of hippocampal, but not cortical, neurons compared to wild-type littermates. Examination of liver, heart, spleen, kidneys, gastro-intestinal tract, muscles, and gonads did not show any other gross abnormalities (See Yang et al., 2003).
HERITABILITY AND MAPPING INFORMATION
Background Strain
C57BL/6J
Heritability Mode
Dominant
Heritability Status
Proven; See Yang et al., 2003
Chromosome
2
Molecular Interval
An approximately 300 kb genomic deletion including Kcnq2, Chrna4 and several other genes.
Map
STATUS INFORMATION
Mutant Status
Cryopreserved Embryos
Comments
Please note: The majority of frozen NMF embryos is obtained through matings between homozygous (or heterozygous) mutant males and wild-type females; if recovery of mutants is requested, the mice will be shipped as soon as possible following wean without further phenotype or genotype testing. NMF embryos are supplied subject to the General Terms and Conditions of Sale posted at www.jaxmice.jax.org. For prices or further information, please inquire at srp@jax.org or nmf-mice@jax.org. (19) SZT1 have been requested by and distributed to 3 investigators.
Contact e-Mail Address
nmf-mice@jax.org