Genetic background effects on age-related hearing loss associated with Cdh23 variants in mice

Hear Res. 2012 Jan;283(1-2):80-8. doi: 10.1016/j.heares.2011.11.007. Epub 2011 Nov 22.


Inbred strain variants of the Cdh23 gene have been shown to influence the onset and progression of age-related hearing loss (AHL) in mice. In linkage backcrosses, the recessive Cdh23 allele (ahl) of the C57BL/6J strain, when homozygous, confers increased susceptibility to AHL, while the dominant allele (Ahl+) of the CBA/CaJ strain confers resistance. To determine the isolated effects of these alleles on different strain backgrounds, we produced the reciprocal congenic strains B6.CBACa-Cdh23(Ahl)(+) and CBACa.B6-Cdh23(ahl) and tested 15-30 mice from each for hearing loss progression. ABR thresholds for 8 kHz, 16 kHz, and 32 kHz pure-tone stimuli were measured at 3, 6, 9, 12, 15 and 18 months of age and compared with age-matched mice of the C57BL/6J and CBA/CaJ parental strains. Mice of the C57BL/6N strain, which is the source of embryonic stem cells for the large International Knockout Mouse Consortium, were also tested for comparisons with C57BL/6J mice. Mice of the C57BL/6J and C57BL/6N strains exhibited identical hearing loss profiles: their 32 kHz ABR thresholds were significantly higher than those of CBA/CaJ and congenic strain mice by 6 months of age, and their 16 kHz thresholds were significantly higher by 12 months. Thresholds of the CBA/CaJ, the B6.CBACa-Cdh23(Ahl)(+), and the CBACa.B6-Cdh23(ahl) strain mice differed little from one another and only slightly increased throughout the 18-month test period. Hearing loss, which corresponded well with cochlear hair cell loss, was most profound in the C57BL/6J and C57BL/6NJ strains. These results indicate that the CBA/CaJ-derived Cdh23(Ahl)(+) allele dramatically lessens hearing loss and hair cell death in an otherwise C57BL/6J genetic background, but that the C57BL/6J-derived Cdh23(ahl) allele has little effect on hearing loss in an otherwise CBA/CaJ background. We conclude that although Cdh23(ahl) homozygosity is necessary, it is not by itself sufficient to account for the accelerated hearing loss of C57BL/6J mice.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Acoustic Stimulation
  • Age Factors
  • Aging
  • Animals
  • Audiometry, Pure-Tone
  • Auditory Threshold
  • Cadherins / genetics*
  • Cadherins / metabolism
  • Cochlea / metabolism
  • Cochlea / pathology
  • Cochlea / physiopathology
  • Disease Models, Animal
  • Evoked Potentials, Auditory, Brain Stem
  • Female
  • Genetic Predisposition to Disease
  • Hair Cells, Auditory / metabolism
  • Hair Cells, Auditory / pathology
  • Male
  • Mice
  • Mice, Congenic
  • Mice, Inbred C57BL
  • Mice, Inbred CBA
  • Mice, Transgenic
  • Phenotype
  • Polymorphism, Single Nucleotide*
  • Presbycusis / genetics*
  • Presbycusis / metabolism
  • Presbycusis / pathology
  • Presbycusis / physiopathology
  • Species Specificity


  • Cadherins
  • Cdh23 protein, mouse