Routine examination for auditory function at 4-5 weeks of age revealed the mutants to be deaf. Acoustic startle response and Auditory brain stem recordings yielded no response at every frequency and intensity tested (click, 8, 16, 32 Hz at 30-90 dB). Mutants of either gender have been produced and the colony is maintained through homozygous breeding. Standard pathology work-up on two mutants (46 or 80 days of age) showed no abnormalities. Serial sections of the ears of the younger mutant showed some slight loss of hair cells in the left ear; whole-mount ear exam performed on the older mutant showed the presence of otoconia and no abnormalities.
