Phenotypes Associated with This Genotype

Genotype
MGI:6278003

• Allelic Composition: Cacna1a^tm3Hzo/Cacna1a^tm3Hzo
• Genetic Background: B6.129S7-Cacna1a^tm3Hzo/J

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

behavior/neurological

impaired balance ( J:239981 )

• mice take longer to traverse the elevated beam at 7 months but not at earlier time points, with mice showing footslips when crossing the narrowest beam

impaired coordination ( J:239981 )

• mice show a motor deficit on the accelerating rotarod at 7 months of age and not earlier, which progressively worsens with age, indicating that disease onset occurs rapidly around 7 months of age

• mice take longer to traverse the elevated beam at 7 months but not at earlier time points, with mice showing footslips when crossing the narrowest beam

• while swimming performance shows no age-dependent differences, mutants produce a small but significant increase in hindlimb kicks at 7 months on the third day

• however, mice do not show gait abnormalities before or at the onset of motor coordination deficits and have normal stride length and width

nervous system

Purkinje cell degeneration ( J:239981 )

• Purkinje cell degeneration occurs at 2 years of age, about 1.5 years after the onset of motor deficits, with 2 year old mice having about 22% fewer Purkinje cells than wild-type mice

• Purkinje cell density is reduced in both anterior and posterior lobules of the vermis

• however, no differences in striatal neuron density is seen at 7 months of age

thin cerebellar molecular layer ( J:239981 )

• average molecular layer thickness is reduced about 15% at 2 years of age compared to at 7 months of age

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
spinocerebellar ataxia type 6		DOID:0050956	OMIM:183086	J:239981