Phenotypes Associated with This Genotype

Genotype
MGI:7496044

• Allelic Composition: Chd7^{Gt(S20-7E1)Sor}/Chd7⁺
• Genetic Background: involves: 129S1/SvImJ * 129S4/SvJae * C57BL/6J * DBA/2J

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

mortality/aging

abnormal induced morbidity/mortality ( J:220430 )

• during exposure to 123 dB broadband noise 7 of 17 mice died

hearing/vestibular/ear

decreased oval window size ( J:220430 )

• generally smaller than in controls

decreased round window size ( J:220430 )

abnormal stapes morphology ( J:220430 )

• fusion of the arch to the dorsal wall of the middle ear cavity

• stapes defects are seen in 5 of 7 mice

abnormal stapes footplate morphology ( J:220430 )

• flattened

• fusion of the footplate to the otic capsule

increased cochlear outer hair cell number ( J:220430 )

• increase in the abundance of supernumerary rows of outer hair cells

abnormal otic capsule morphology ( J:220430 )

• fusion of the stapedial footplate to the otic capsule

increased or absent threshold for auditory brainstem response ( J:220430 )

• increased mean thresholds at 4 kHz and 16 kHz but not at 32 kHz at 5 weeks of age

• increase in thresholds correlates with the absence of a free stapes

absent distortion product otoacoustic emissions ( J:220430 )

• flattened or absent at the mid-frequency range (8, 16, and 24 kHz) in most mice

decreased susceptibility to noise-induced hearing loss ( J:220430 )

• of the 10 mice that survived exposure to 123 dB broadband noise, 6 showed no inner or outer hair cell loss, normal distribution of nerve fibers in the cochlea and no change in hearing thresholds unlike exposure-matched controls

• the other 4 mice showed responses similar to exposure-matched controls

• resistance to noise-induced hearing loss correlates with presence of a fixed stapes

impaired hearing ( J:220430 )

• mild hearing loss at low to mid frequencies

conductive hearing impairment ( J:220430 )

sensorineural hearing impairment ( J:220430 )

craniofacial

decreased oval window size ( J:220430 )

• generally smaller than in controls

decreased round window size ( J:220430 )

abnormal stapes morphology ( J:220430 )

• fusion of the arch to the dorsal wall of the middle ear cavity

• stapes defects are seen in 5 of 7 mice

abnormal stapes footplate morphology ( J:220430 )

• flattened

• fusion of the footplate to the otic capsule

skeleton

decreased oval window size ( J:220430 )

• generally smaller than in controls

decreased round window size ( J:220430 )

abnormal stapes morphology ( J:220430 )

• fusion of the arch to the dorsal wall of the middle ear cavity

• stapes defects are seen in 5 of 7 mice

abnormal stapes footplate morphology ( J:220430 )

• flattened

• fusion of the footplate to the otic capsule

nervous system

increased cochlear outer hair cell number ( J:220430 )

• increase in the abundance of supernumerary rows of outer hair cells

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
CHARGE syndrome		DOID:0050834	OMIM:214800	J:220430