Genetic Influences on Auditory Function in Companion Animals

Hereditary hearing loss in companion animals arises from a spectrum of genetic variants affecting cochlear development, melanocyte migration and neural integrity. In many dog breeds and certain cat populations, congenital sensorineural deafness (CSD) co-segregates with coat pigmentation genes, notably those governing extreme-white patterns and piebald spotting. Key transcription factors and pigment pathway genes, including MITF, KIT and EDNRB, influence melanocyte presence in the stria vascularis, with absence of cochlear melanocytes leading to cochleo-saccular degeneration. Other forms of hereditary deafness reflect neuroepithelial pathology unlinked to pigmentation, implicating genes such as CDH23 and KLF7. Heritability estimates in dogs range from moderate to high, and complex segregation analyses often rule out single-locus inheritance, underscoring polygenic architectures and variable penetrance. Adult-onset hearing loss models in working breeds reveal autosomal dominant patterns distinct from congenital forms. Advances in genome-wide association studies, fine-mapping of quantitative trait loci and haplotype analyses have begun to pinpoint risk regions, offering tools for selective breeding and potential translational insights into human auditory disorders.

Research from Nature Portfolio

Genome-wide meta-analysis in Dalmatian dogs has defined a significant risk haplotype on chromosome 20 near the MITF region, formed by three single-nucleotide variants. This haplotype confers up to a tenfold increased risk of bilateral deafness, while heterozygosity correlates with unilateral hearing loss. Integration of datasets from major global populations enhanced statistical power, revealing a core risk interval. Although causative mutations remain to be identified, these findings establish a target for breeding programmes and functional studies on melanocyte regulation in the inner ear.

Genetic Influences on Auditory Function in Companion Animals publication trend

The graph below shows the total number of articles in genetic influences on auditory function in companion animals across all publications each year (not limited to Nature Index journals).

Technical terms

Congenital sensorineural deafness: Hearing loss present at birth due to dysfunction of cochlear hair cells or auditory nerve pathways.

Heritability: The proportion of phenotypic variance in a trait attributable to genetic variation in a population.

Piebald locus: A genetic region controlling white spotting patterns, often linked to melanocyte absence in the inner ear.

Genome-wide association study (GWAS): A method that scans the entire genome to identify genetic variants statistically associated with a trait.

Quantitative trait locus (QTL): A chromosomal segment containing one or more genes that contribute to variation in a quantitative trait.

Brainstem auditory evoked response (BAER): An electrophysiological test recording neural responses from the auditory nerve and brainstem following sound stimulation.

Haplotype: A set of DNA variations, or polymorphisms, that tend to be inherited together on the same chromosome.

Penetrance: The proportion of individuals carrying a particular variant who exhibit the associated phenotype.

Melanocyte Inducing Transcription Factor (MITF): A master regulator of melanocyte development and pigment cell survival, implicated in extreme-white coat patterns and sensory defects.

References

1. The Genetics of Deafness in Domestic Animals. Frontiers in Veterinary Science (2015).
2. Heritability and Segregation Analysis of Deafness in U.S. Dalmatians. Genetics (2004).
3. An analysis of the inheritance pattern of an adult-onset hearing loss in Border Collie dogs. Companion Animal Health and Genetics (2014).
4. Congenital Sensorineural Deafness in Dalmatian Dogs Associated with Quantitative Trait Loci. PLOS ONE (2013).
5. De-novo and genome-wide meta-analyses identify a risk haplotype for congenital sensorineural deafness in Dalmatian dogs. Scientific Reports (2022).
6. A genome-wide association study of deafness in three canine breeds. PLOS ONE (2020).
7. A Missense Mutation in the KLF7 Gene Is a Potential Candidate Variant for Congenital Deafness in Australian Stumpy Tail Cattle Dogs. Genes (2021).
8. Sensorineural deafness in purebred white Devon Rex cats. Journal of Veterinary Internal Medicine (2024).