General Terms and Conditions

Mammalian Phenotype Terms assigned by genotype

Ctnna2^cdf/Ctnna2⁺

        C3H/HeSnJ-Ctnna2^cdf/J

• hearing/vestibular/ear phenotype
• abnormal linear vestibular evoked potential (J:116914)
  • suprisingly, mice show improved threshold compared to controls

Ctnna2^cdf/Ctnna2^cdf

        C3H/HeSnJ-Ctnna2^cdf/J

• behavior/neurological phenotype
• abnormal cued conditioning behavior (J:77488)
  • a test in which an auditory cue was coupled with a foot shock failed to elicit a startle response to the auditory cue after training in mutant mice
• abnormal maternal nurturing (J:38887)
  • females take poor care of offspring
• abnormal tail movements (J:38887)
  • mice often hold their tails off the surface when walking and sometimes arch the tail over their backs
• ataxia (J:38887)
  • described as a side-to-side wobble
• increased startle reflex (J:77488)
  • the amplitude of the acoustic startle response was larger in mutant mice
• limb grasping (J:38887)
• growth/size phenotype
• decreased body weight (J:38887)
  • mice weigh approximately 25% less than littermate controls before weaning, mice weigh approximately 50% less than littermate controls throughout adulthood
• hearing/vestibular/ear phenotype
• *normal* hearing/vestibular/ear phenotype (J:77488)
  • mice exhibit normal auditory brainstem (ABR) responses indicating that mutant mice can hear normally
• increased startle reflex (J:77488)
  • the amplitude of the acoustic startle response was larger in mutant mice
• reduced linear vestibular evoked potential (J:116914)
  • elevated threshold
• hematopoietic system phenotype
• increased erythrocyte cell number (J:38887)
  • slightly higher than controls, but within values expected for the background strain
• reproductive system phenotype
• reduced male fertility (J:38887)
  • males rarely breed
• nervous system phenotype
• *normal* nervous system phenotype (J:38887)
  • EEG patterns were similar to controls
  • normal histopathology of the cerebrum, thalamus, brainstem, spinal cord was noted
• abnormal cerebellar foliation (J:70222)
  • the precentral fissure between lobules II and III is rudimentary
  • folia is reduced to 7 as contrasted with the wild type folia count of 10; foliation pattern is also perturbed
  • absence of intraculmenate fissure that divides the culmen into two lobules, 4 and 5
  • absence of the declivis 6a and 6b
  • absence of fissura seconda that separates the pyramis 8 from the uvula 9
  • absence of uvula 9b and 9c
  • at P0 and P2, cerebella lacked fissures unlike controls
  • the prepyramidal fissure appeared at P8
• abnormal cerebellar granule layer (J:38887)
  • reduced number of granule cells were observed at 5 months of age
• abnormal cerebellar lobule formation (J:70222)
  • most lobules are shortened in length
  • lobulation began between P2 and P4 instead of P0 as in controls
  • lobulation continued to be delayed past the first postnatal week
• abnormal prepulse inhibition (J:77488)
  • a weaker PPI was seen compared to controls
• abnormal vermis morphology (J:38887)
  • mineral deposits seen in the ventral vermis of the midline
  • vermis is reduced in rostro-caudal length by more than one third
• decreased pyramidal neuron number (J:74540)
  • in the pyramidal cell layer, pyramidal cells were less densely packed compared to wild type mice, and occasionally appears as isolated cells
• ectopic Purkinje cell (J:38887)
  • Purkinje cells were observed in the granule cell layer and in the white matter
  • a failure of Purkinje cell migration during development results in widespread ectopia in the adult
  • the cells are not arranged in the normal monolayer in the cerebellum and appear in the deep core of the cerebellum, the granular layer, and the intralobular white matter
  • total numbers of Purkinje cells appeared similar in mutant mice and controls
  • ectopic Purkinje cells were those primarily not expressing zebrin II
  • at P0, Purkinje cells are scattered throughout the white matter
  • at P4, some Purkinje cells had aligned in a single layer, but many remained at ectopic sites
• ectopic pyramidal neurons (J:74540)
  • pyramidal cells of the CA1, CA2, and CA3 region were scattered into the external and deep plexiform layers of the hippocampus
• small cerebellum (J:70222)
  • reduced in overall size compared to controls
• cerebellum hypoplasia (J:38887)
  • midsagittal area of the mutant cerebellum is ~60% that of control mice