Phenotypes for Slc26a4 MGI:2385830 MGI Mouse

absent pinna reflex ( J:67072 )

• failed to exhibit a Preyer's reflex to a loud clap

impaired coordination ( J:67072 )

• impairment on a rotarod test

head bobbing ( J:67072 )

• pronounced head bobbing at 3 weeks of age

head tilt ( J:67072 )

• pronounced head tilting at 3 weeks of age

abnormal gait ( J:67072 )

• gait unsteadiness evident upon beginning to walk

circling ( J:67072 )

• profound circling behavior at 3 weeks of age

abnormal inner ear morphology ( J:67072 )

• defects detectable at E15

distended Reissner membrane ( J:67072 )

• bulging due to dilation of scala media observed at P1

dilated cochlea ( J:67072 )

• dilated cochlea observed at E15.5-E16.5

fused inner hair cell stereocilia ( J:67072 )

• in some cases, IHC degeneration is associated with enlarged stereocilia

cochlear inner hair cell degeneration ( J:67072 )

• inner hair cell degeneration starting between P7 and P15, with variation among different cochleas as well as areas of the same cochlea

cochlear outer hair cell degeneration ( J:67072 )

• outer hair cell degeneration starting between P7 and P15, with considerable variation among different cochleas as well as areas of the same cochlea

dilated scala media ( J:67072 )

• dilated scala media at P1

abnormal semicircular canal morphology ( J:67072 )

• some mice develop dilated semicircular canals

utricular macular degeneration ( J:67072 )

vestibular saccular macula degeneration ( J:67072 )

enlarged vestibular saccule ( J:67072 )

• dilated saccule observed at E15.5-E16.5

dilated endolymphatic duct ( J:67072 )

• dilated endolymphatic duct starting at E15

dilated endolymphatic sac ( J:67072 )

• dilated endolymphatic sac starting at E15

abnormal otolithic membrane morphology ( J:67072 )

• destruction of the otoconial membrane

absent otoliths ( J:67072 )

• almost complete absence of otoconia

enlarged otoliths ( J:67072 )

• at P30, occasional presence of giant otoconia, when present

increased or absent threshold for auditory brainstem response ( J:67072 )

• failed to show characteristic waveforms by auditory-evoked brainstem response analyses

deafness ( J:67072 )

• at P28-P42, homozygotes show no characteristic ABR waveforms at intensities up to 100 dB SPL and with all four test stimuli, indicating complete hearing loss

sensorineural hearing loss ( J:67072 )

abnormal vestibular system physiology ( J:67072 )

• ~50% of homozygotes exhibit various signs of vestibular dysfunction, including habitual circling behaviour, head-tilting and head-bobbing and/or an abnormal reaching response

• vestibular dysfunction shows variable expressivity with respect to its presence, features and severity, but not age of onset