Whole genome sequencing identifies genetic candidates for high-frequency hearing loss in canaries (serinus canaria)

Over hundreds of years, breeders have selectively bred different strains of canaries for plumage and song characteristics. One strain, the Belgian Waterslager canary, has been bred for loud, low frequency song and coincidently has been found to have a high-frequency hearing loss due to damaged and missing hair cells in the basilar papilla. Here, we investigated the possible genetic basis for this hearing loss in the Belgian Waterslager canary by conducting whole-genome Illumina (San Diego, CA) sequencing in three canary strains. We identified a total of 16 Belgian Waterslager male-specific "high-impact" single nucleotide polymorphisms (SNP) variants with three mutations occurring within genes previously identified in mammalian hair cell abnormalities and hearing loss disorders: pericentriolar material 1 (PCM1), p21 (RAC1) activated kinase 3 (PAK3)-like, and protein tyrosine phosphatase receptor type K (PTPRK). Interestingly, we also identified three male-specific "high-impact" SNP variants in one of our control strains: the American Singer canary. One of these mutations occurs within genes previously associated with hearing loss in mammals. Since songbirds rely on hearing to develop a normal vocal repertoire, investigating the role of these genes in hearing loss at the molecular level may provide a valuable animal model for examining the relationship between hearing loss and vocal development in humans.