Phenotypes associated with this allele

• Allele Symbol: Slc9a1^swe
• Allele Name: slow-wave epilepsy
• Allele ID: MGI:1857350
• Summary: 4 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Slc9a1^swe/Slc9a1^swe	B6.SJL-Slc9a1^swe	MGI:3623149
hm2	Slc9a1^swe/Slc9a1^swe	involves: C57BL/6J * SJL/J	MGI:3623151
hm3	Slc9a1^swe/Slc9a1^swe	SJL/J-Slc9a1^swe/J	MGI:3581202
hm4	Slc9a1^swe/Slc9a1^swe	(SJL/J-Slc9a1^swe x B6.SJL-Slc9a1^swe)F1	MGI:3714370

Genotype
MGI:3623149

hm1

• Allelic Composition: Slc9a1^swe/Slc9a1^swe
• Genetic Background: B6.SJL-Slc9a1^swe

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

mortality/aging

premature death ( J:43429 )

• most animals surviving past weaning die by 35-40 days of age probably from a lethal convulsive episode; B6.SJL congenics rarely live past 40 days of age

postnatal lethality, incomplete penetrance ( J:43429 )

• more than half of the homozygotes die before weaning

growth/size/body

decreased body size ( J:43429 )

• mutants are slightly smaller than wild-type littermates at weaning

behavior/neurological

ataxia ( J:43429 )

• at 11-14 days of age, mutants have an ataxic gait; ataxia is more prominent in the hindlimbs and is characterized by a slow, wide-based gait and coarse truncal instability while moving

seizures ( J:43429 )

• brief episodes of 3/second waves and spike wave patterns are observed in 5 nd 6 week old animals, but do not progress with age

tonic-clonic seizures ( J:43429 )

• mutants undergo rare spontaneous generalized tonic-clonic seizure episodes as early as 14 days of age; seizures are usually of less than one minute and are preceded by several seconds of wild running

nervous system

seizures ( J:43429 )

• brief episodes of 3/second waves and spike wave patterns are observed in 5 nd 6 week old animals, but do not progress with age

tonic-clonic seizures ( J:43429 )

• mutants undergo rare spontaneous generalized tonic-clonic seizure episodes as early as 14 days of age; seizures are usually of less than one minute and are preceded by several seconds of wild running

abnormal cerebellar molecular layer ( J:43429 )

• occasional dystrophic axons are seen in and around the cerebellar molecular layer

abnormal cerebellum deep nucleus morphology ( J:43429 )

• progressive neuronal degeneration is observed in deep cerebellar nuclei at 3 weeks of age; by 7 weeks and more so at 4 months, most DCN large neurons have disappeared; surviving neurons are surrounded by excessive glial cells

abnormal cerebellum dentate nucleus morphology ( J:43429 )

• by 7 weeks and more so at 4 months, most DCN large neurons have disappeared; surviving neurons are surrounded by excessive glial cells

abnormal axon morphology ( J:199873 )

• Purkinje cell axons are hypertrophic

abnormal Purkinje cell axon morphology ( J:199873 )

• Purkinje cell axons are hypertrophic

abnormal synaptic bouton morphology ( J:199873 )

• swollen and displaced Purkinje cell axon collateral boutons are seen as early as P14

neuron degeneration ( J:43429 )

• progressive neuronal degeneration is observed in deep cerebellar nuclei at 3 weeks of age; by 7 weeks and more so at 4 months, most DCN large neurons have disappeared; surviving neurons are surrounded by excessive glial cells

Purkinje cell degeneration ( J:199873 )

• Purkinje cell axon degeneration in the cerebella at 4 months of age

• however, no loss of Purkinje cells is detected in the cerebellum

cochlear ganglion degeneration ( J:43429 )

• progressive degeneration of cochlear nuclei is also observed but fewer neurons are affected at each timepoint examined

abnormal vestibular ganglion morphology ( J:43429 )

• progressive degeneration of vestibular nuclei is also observed but fewer neurons are affected at each timepoint examined

axon degeneration ( J:199873 )

• Purkinje cell axon degeneration in the cerebella at 4 months of age

Genotype
MGI:3623151

hm2

• Allelic Composition: Slc9a1^swe/Slc9a1^swe
• Genetic Background: involves: C57BL/6J * SJL/J

mortality/aging

premature death ( J:43429 )

• Background Sensitivity: most of the affected F1 and F2 hybrids survive 6 months

behavior/neurological

behavioral arrest ( J:43429 )

• associated with absence seizures

seizures ( J:43429 )

• Background Sensitivity: spike-wave seizure activity is markedly enhanced compared to homozygotes on congenic backgrounds; seizures are longer in duration and very frequent by 4 weeks of age and persist several months

tonic-clonic seizures ( J:43429 )

• mutants undergo rare spontaneous generalized tonic-clonic seizure episodes as early as 14 days og age; seizures are usually of less than one minute and are preceded by several seconds of wild running

absence seizures ( J:43429 )

• electrocorticographic recording from 4-5 week old (SJL x B6) F2 mutants display frequent episodes of generalized bilaterally symmetric spike-wave activity with a rhythmic periodicity ranging from 3 to 4.5 seconds; spikes are always preceded by waves; spike wave bursts are specifically associated with complete behavioral arrest for the durationof the discharge

nervous system

seizures ( J:43429 )

• Background Sensitivity: spike-wave seizure activity is markedly enhanced compared to homozygotes on congenic backgrounds; seizures are longer in duration and very frequent by 4 weeks of age and persist several months

tonic-clonic seizures ( J:43429 )

• mutants undergo rare spontaneous generalized tonic-clonic seizure episodes as early as 14 days og age; seizures are usually of less than one minute and are preceded by several seconds of wild running

absence seizures ( J:43429 )

• electrocorticographic recording from 4-5 week old (SJL x B6) F2 mutants display frequent episodes of generalized bilaterally symmetric spike-wave activity with a rhythmic periodicity ranging from 3 to 4.5 seconds; spikes are always preceded by waves; spike wave bursts are specifically associated with complete behavioral arrest for the durationof the discharge

Genotype
MGI:3581202

hm3

• Allelic Composition: Slc9a1^swe/Slc9a1^swe
• Genetic Background: SJL/J-Slc9a1^swe/J

Slc9a1^swe/Slc9a1^swe with Slc9a1^swe/⁺ at 4 weeks of age

mortality/aging

premature death ( J:43429 )

• 62% die by weaning and, with rare exception, the remainder die by 35-40 days of age probably from a lethal convulsive episode

• Background Sensitivity: only an occasional mutant on the SJL background survives beyond 6 months

postnatal lethality ( J:43429 )

• more than half of the homozygotes die before weaning

behavior/neurological

abnormal locomotor coordination ( J:43429 )

ataxia ( J:43429 )

• mutant mice are easily recognizeable from normal siblings by 11-14 days of age based on their ataxic gait and smaller size

• ataxia is moderate to severe most prominent in the hindlimbs

abnormal gait ( J:43429 )

• affected mice have a wide-based gait

seizures ( J:43429 )

• Background Sensitivity: spike-wave discharges from homozygotes are detected at 4-5 weeks but are brief (less than 1.5 sec) and rare (1-4/hour) and do not progress in duration or frequency when assessed at 2-3 months of age; these are not detected in mice surviving beyond months

tonic-clonic seizures ( J:43429 )

• mutants undergo rare spontaneous generalized tonic-clonic seizure episodes as early as 14 days og age; seizures are usually of less than one minute and are preceded by several seconds of wild running

nervous system

seizures ( J:43429 )

• Background Sensitivity: spike-wave discharges from homozygotes are detected at 4-5 weeks but are brief (less than 1.5 sec) and rare (1-4/hour) and do not progress in duration or frequency when assessed at 2-3 months of age; these are not detected in mice surviving beyond months

tonic-clonic seizures ( J:43429 )

• mutants undergo rare spontaneous generalized tonic-clonic seizure episodes as early as 14 days og age; seizures are usually of less than one minute and are preceded by several seconds of wild running

growth/size/body

growth/size/body region phenotype ( J:43429 )

N

decreased body size ( J:43429 )

• affected mice are recognizeable from normal siblings at 11-14 days of age based on slightly smaller size and ataxic gait

Genotype
MGI:3714370

hm4

• Allelic Composition: Slc9a1^swe/Slc9a1^swe
• Genetic Background: (SJL/J-Slc9a1^swe x B6.SJL-Slc9a1^swe)F1

mortality/aging

premature death ( J:43429 )

preweaning lethality, incomplete penetrance ( J:43429 )

• Background Sensitivity: 33% of mutants die before weaning compared to 62% on an SJL background