Phenotypes Associated with This Genotype

Genotype
MGI:3588875

• Allelic Composition: Gjb2^tm1Ugds/Gjb2^tm1Ugds; Tg(Otog-cre)1Ugds/0
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6

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

hearing/vestibular/ear

abnormal cochlear inner hair cell morphology ( J:77823 )

• direct efferent synapses are present on inner hair cells

abnormal inner hair cell synaptic ribbon morphology ( J:77823 )

• several synaptic ribbons, instead of the usual single one, are frequently observed in the active zone of the inner hair cell synaptic area

cochlear outer hair cell degeneration ( J:77823 )

• outer hair cells are damaged or lost

degeneration of organ of Corti supporting cells ( J:77823 )

• supporting cells of outer hair cells are damaged or lost

abnormal interdental cell morphology ( J:77823 )

• at P60, some interdental cells of the spiral limbus are missing

cochlear degeneration ( J:77823 )

• observe death of various cells in the cochlea that is not seen in wild-type

organ of Corti degeneration ( J:77823 )

• organ of Corti tends to collapse starting at P15-P16

• many epithelial cells have an altered shape and the reticular lamina is disrupted

abnormal cochlear endolymph ionic homeostasis ( J:77823 )

• decreased endolymphatic K⁺ concentration

decreased endocochlear potential ( J:77823 )

increased or absent threshold for auditory brainstem response ( J:77823 )

• 4 inner ears out of 41 had a hearing threshold > 100 dB sound pressure level (SPL)

sensorineural hearing loss ( J:77823 )

• at 3 to 12 weeks of age, mice showed a significant hearing loss, compared to heterozygous and control mice, for all frequencies tested; it ranged from 30 dB to more than 70 dB, with an average of 30 dB at 8 kHz, 31 dB at 16 kHz, and 36 dB at 32 kHz

• analysis of mutant mice individually showed that the hearing loss was more pronounced at 32 kHz than at 8 kHz

nervous system

abnormal cochlear inner hair cell morphology ( J:77823 )

• direct efferent synapses are present on inner hair cells

abnormal inner hair cell synaptic ribbon morphology ( J:77823 )

• several synaptic ribbons, instead of the usual single one, are frequently observed in the active zone of the inner hair cell synaptic area

cochlear outer hair cell degeneration ( J:77823 )

• outer hair cells are damaged or lost

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
autosomal recessive nonsyndromic deafness 1A		DOID:0110475	OMIM:220290	J:77823