Variability of Auditory Brainstem Responses in Diversity Outbred Mice

Inbred mouse strains are mainly used in hearing research as animal models. Most of these lab mice strains consist of genetically identical individuals and natural variability as it is found in wild populations is not represented. Jackson Laboratories generated a new mice strain by an outbred of different mice strains to create mice with different pheno- and genotype, the Diversity Outbred strain (J:DO). By using 20 J:DO mice at the age of eight to nine weeks, we aimed to test the hearing variability in auditory thresholds and measured auditory brainstem responses at 15 different frequencies and sound pressure level from 0 to 80 dB SPL. Our measurements revealed a wide hearing bandwidth in J:DO mice that span over about 4.5 octaves. The high-frequency cut-off of the hearing threshold varied from 21 to 80 kHz and was on median at 64 kHz. Whereas the low frequency cut-off was at 3 kHz with low variation. The median characteristic frequency was found at 15 kHz and showed not a high variation in the sound level to induce an ABR threshold (20 dB SPL). We found not differences in hearing between male and female J:DOs. Future studies on hearing impairments in mice that aim to base on a genetically variable population could benefit from this new mouse strain and use our dataset on the hearing threshold in J:DO mice is a basis.