Phenotypes associated with this allele

• Allele Symbol: Fbxo2^tm1Hlp
• Allele Name: targeted mutation 1, Henry L Paulson
• Allele ID: MGI:3711101
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Fbxo2^tm1Hlp/Fbxo2^tm1Hlp	B6.129-Fbxo2^tm1Hlp	MGI:3711697

Genotype
MGI:3711697

hm1

• Allelic Composition: Fbxo2^tm1Hlp/Fbxo2^tm1Hlp
• Genetic Background: B6.129-Fbxo2^tm1Hlp

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

hearing/vestibular/ear

abnormal cochlear hair cell morphology ( J:121568 )

• at 2- and 3.5 months of age, TEM analysis indicates aberrant juxtamembranous, tubulovesicular structures in mutant cochlear hair cells

cochlear hair cell degeneration ( J:121568 )

• at 3-5 months of age, homozygotes display hair cell degeneration

abnormal Claudius cell morphology ( J:121568 )

• at 2- and 3.5 months of age, TEM analysis indicates disruption of Claudius' cells membrane integrity

abnormal organ of Corti supporting cell morphology ( J:121568 )

• at 3.5 months of age, an asymmetric, juxtamembranous accumulation of membranous structures is found in supporting cells of the organ of Corti

degeneration of organ of Corti supporting cells ( J:121568 )

• at 6 weeks of age, homozygotes display a loss of supporting cells while hair cells in the organ of Corti are still present

• supporting cells between the outer hair cells and the spiral ligament appear to be lost first

• between 2 and 3.5 months, mutants show dysmorphic changes in the inner sulcus supporting cells, located between the inner hair cell and spiral limbus, while the spiral ganglion remains intact

cochlear degeneration ( J:121568 )

• homozygotes develop age-related cochlear degeneration with cellular changes first noted between 1 and 3.5 months, whereas milder degenerative changes are not observed in wild-type mice until ~11 months

abnormal auditory brainstem response waveform shape ( J:121568 )

• at 2 months of age, homozygotes exhibit altered ABR waveforms relative to wild-type mice, with thresholds of 50 and 15 dB, respectively

• however, no changes in ABR thresholds and waveforms are noted at 1 month of age

increased or absent threshold for auditory brainstem response ( J:121568 )

• by 9-12 months of age, ~50% of homozygotes have no ABR responses

increased susceptibility to age-related hearing loss ( J:121568 )

• at 2 months of age, homozygotes begin to develop hearing loss which becomes evident at 2-4 months

• by 9 months of age, ~50% of homozygotes display no ABR response and are classified as deaf

• homozygotes exhibit much earlier and more profound hearing deficits relative to C57BL/6 control mice

deafness ( J:121568 )

• by 9 months of age, ~50% of homozygotes are deaf, as shown by absence of ABR responses

nervous system

nervous system phenotype ( J:121568 )

N • despite widespread CNS expression, no defects in brain development or gross adult brain structure are observed

abnormal cochlear hair cell morphology ( J:121568 )

• at 2- and 3.5 months of age, TEM analysis indicates aberrant juxtamembranous, tubulovesicular structures in mutant cochlear hair cells

cochlear hair cell degeneration ( J:121568 )

• at 3-5 months of age, homozygotes display hair cell degeneration

cochlear ganglion degeneration ( J:121568 )

• at 3-5 months of age, homozygotes display neuronal degeneration in the spiral ganglion

behavior/neurological

behavior/neurological phenotype ( J:121568 )

N • homozygotes are viable, fertile and overtly normal with no behavioral deficits such as circling or whirling, suggesting normal vestibular function