Mouse Genome Informatics
hm1
    Otoftm1Ugds/Otoftm1Ugds
involves: 129S2/SvPas * C57BL/6
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
hearing/vestibular/ear
N
• outer hair cells (OHC) and afferent auditory pathway (auditory nerve) are functional in adults (J:116097)
• structurally abnormal ribbon synapse postsynaptic contacts are observed at P15
• inner hair cells (IHC) of mutants have ~50-60% of normal number of ribbon synapses at P15
• depolarization-induced exocytosis of immature (P6) and mature (P15) inner hair cells (IHC) is almost completely abolished in mutants; exocytosis of readily releasable pool (RRP) and sustained secretion of neurotransmitter are both affected
• IHCs lack the fast component of the exocytotic burst even at high calcium concentrations, and slow component is maintained at a smaller amplitude than in wild-type
• mutants analyzed from 3 weeks of age onward show no visible auditory brainstem responses (ABRs) to any intensity of click or tone stimulation
• profoundly deaf

nervous system
• structurally abnormal ribbon synapse postsynaptic contacts are observed at P15
• inner hair cells (IHC) of mutants have ~50-60% of normal number of ribbon synapses at P15
• depolarization-induced exocytosis of immature (P6) and mature (P15) inner hair cells (IHC) is almost completely abolished in mutants; exocytosis of readily releasable pool (RRP) and sustained secretion of neurotransmitter are both affected
• IHCs lack the fast component of the exocytotic burst even at high calcium concentrations, and slow component is maintained at a smaller amplitude than in wild-type

Mouse Models of Human Disease
OMIM IDRef(s)
Deafness, Autosomal Recessive 9; DFNB9 601071 J:116097