Phenotypes Associated with This Genotype

Genotype
MGI:3804682

• Allelic Composition: Slc17a8^tm1Selm/Slc17a8^tm1Selm
• Genetic Background: involves: 129/Sv * C57BL/6

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

hearing/vestibular/ear

hearing/vestibular/ear phenotype ( J:139493 )

N • mice exhibit normal distortion product otoacoustic emissions and synaptic-membrane turnover in inner hair cells despite the inability to load and release glutamate

N • mice exhibit normal inner hair cell-afferent synapses

decreased cochlear inner hair cell number ( J:139493 )

• a few scattered inner hair cells are missing (less than 1% of the total number) compared to in wild-type mice

abnormal cochlear IHC efferent innervation pattern ( J:139493 )

• the number of lateral efferent endings is decreased 70% in the basal turn and 43% in the medial turn compared to in wild-type mice

abnormal inner hair cell synaptic ribbon morphology ( J:139493 )

• at 3 months, the number of presynaptic ribbons at the inner hair cell synapse is reduced compared to in wild-type mice

abnormal cochlear inner hair cell physiology ( J:139493 )

• calcium ion currents in inner hair cells are greater than in wild-type cells

abnormal auditory brainstem response ( J:139493 )

• electrically stimulated auditory brainstem response amplitude is slightly reduced compared to in wild-type mice

increased or absent threshold for auditory brainstem response ( J:139493 )

• mice fail to exhibit sound-evoked auditory brainstem response (ABR) unlike wild-type mice

• however, mice exhibit normal electrically stimulated ABR unless treated with TTX

absent cochlear nerve compound action potential ( J:139493 )

• mice fail to show any visible compound action potential response, even for stimulus intensities of 100 dB SPL

• however, mice exhibit normal membrane capacitance and summating potential amplitude intensity functions

deafness ( J:139493 )

behavior/neurological

enhanced behavioral response to cocaine ( J:135586 )

• induced horizontal activity was markedly higher in mutant mice than in control after administration of cocaine

impaired behavioral response to xenobiotic ( J:135586 )

• decreased sensitivity of mutant mice to haloperidol as measured by induced catalepsy

increased locomotor activity ( J:135586 )

• hyperactive in home cage measured by spontaneous horizontal locomotor activity

• no major histological changes were detected in the brains

• none of the sensorimotor skills, fine motor coordination and reflexes were impaired

nervous system

decreased cochlear inner hair cell number ( J:139493 )

• a few scattered inner hair cells are missing (less than 1% of the total number) compared to in wild-type mice

abnormal cochlear IHC efferent innervation pattern ( J:139493 )

• the number of lateral efferent endings is decreased 70% in the basal turn and 43% in the medial turn compared to in wild-type mice

abnormal inner hair cell synaptic ribbon morphology ( J:139493 )

• at 3 months, the number of presynaptic ribbons at the inner hair cell synapse is reduced compared to in wild-type mice

abnormal cochlear inner hair cell physiology ( J:139493 )

• calcium ion currents in inner hair cells are greater than in wild-type cells

absent cochlear nerve compound action potential ( J:139493 )

• mice fail to show any visible compound action potential response, even for stimulus intensities of 100 dB SPL

• however, mice exhibit normal membrane capacitance and summating potential amplitude intensity functions

abnormal cochlear ganglion morphology ( J:139493 )

• the number of spiral ganglion is reduced 42% compared to in wild-type mice without evidence of degeneration

abnormal synaptic acetylcholine release ( J:135586 )

• a slightly increased turnover of acetylcholine in the striatum

• reduced ACh release evoked by the glutamatergic agonist NMDA in mutant brain slices

abnormal neurotransmitter uptake ( J:135586 )

• the loss of a synergistic effect of glutamate on vesicular acetylcholine uptake

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
autosomal dominant nonsyndromic deafness 25		DOID:0110555	OMIM:605583	J:139493