Phenotypes Associated with This Genotype

Genotype
MGI:6197507

• Allelic Composition: Mctp1^dwnd/Mctp1^dwnd
• Genetic Background: B6.B10Sn-Mctp1^dwnd/Kjn

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

behavior/neurological

circling ( J:264553 )

• homozygotes have a moderate circling phenotype, but penetrance is only approximately 35% so this is not a reliable phenotypic determinant.

mortality/aging

mortality/aging ( J:264553 )

N • Homozygotes do not display postnatal lethality

nervous system

abnormal cochlear hair cell morphology ( J:264553 )

abnormal cochlear inner hair cell morphology ( J:264553 )

• additional, disorganized inner hair cells are found near the chochlear base, and the density of inner hair cells near the apex and base of the cochlea is greater than in controls, but the cochlea is shorter than normal so the total hair cell number may not be abnormal

abnormal cochlear outer hair cell morphology ( J:264553 )

• homozygotes have an extra row of outer hair cells at the cochlear apex, although the cochlea is shorter than normal so the total number of hair cells may not be abnormal

hearing/vestibular/ear

abnormal cochlea morphology ( J:264553 )

• the cochlea is smaller and shorter than that of controls

abnormal scala media morphology ( J:264553 )

• shorter than normal

abnormal cochlear hair cell morphology ( J:264553 )

abnormal cochlear inner hair cell morphology ( J:264553 )

• additional, disorganized inner hair cells are found near the chochlear base, and the density of inner hair cells near the apex and base of the cochlea is greater than in controls, but the cochlea is shorter than normal so the total hair cell number may not be abnormal

abnormal cochlear outer hair cell morphology ( J:264553 )

• homozygotes have an extra row of outer hair cells at the cochlear apex, although the cochlea is shorter than normal so the total number of hair cells may not be abnormal

small scala media ( J:264553 )

abnormal vestibular saccule morphology ( J:264553 )

• saccule is smaller than normal and not fully separated from the utricle

abnormal vestibular saccule duct morphology ( J:264553 )

• duct connecting the saccule and cochlea is larger than normal

fused vestibular saccule and utricle ( J:264553 )

• the saccule does not fully separate from the utricle

small vestibular saccule ( J:264553 )

• the saccule is smaller than normal

increased or absent threshold for auditory brainstem response ( J:264553 )

• all homozygotes have hearing impairment, with ABR thresholds 20-30 dB higher than controls at one month of age and 25-45 dB higher than controls at six months of age