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.
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).
|Allele Name||seizure threshold 1|
|Gene Symbol and Name||Szt1, seizure threshold 1|
|Strain of Origin||C57BL/6J|
|Molecular Note||The Szt1 mutation represents a genomic deletion of about 300 kb of mouse chromosome 2. The deletion involves 3 known genes including those encoding the potassium channel, Kcnq2, and the nicotinic acetylcholine receptor subunit, Chrna4, and ADP-ribosylation factor GTPase activating protein 1, Arfgap1.|
When using the seizure threshold 1 mouse strain in a publication, please cite the originating article(s) and include JAX stock #004587 in your Materials and Methods section.