Genome-wide association study for tobiano spotting coat color in Korean Jeju × Thoroughbred horse population

Korean Jeju horse features a small to medium frame size and stature having varieties of coat colors including grey, milky, spotted and bay1. Crossbreeding with Thoroughbred has been a long tradition in Korea to have intermediate frame size horse suitable for racing, leisure activities and meat production2. Tobiano white-spotting pattern is preferred by many horse breeders and owners which is inherited as an autosomal dominant trait1,3. Polymorphisms in proto-oncogene receptor tyrosine kinase (KIT) gene were strongly associated with tobiano and sabino coat color pattern in American and European horse breeds3,5. In addition, ECA3 inversion locus near KIT gene also significantly associated with tobiano spotting pattern in horses4,5. Here, we report SNPs and harbored genes associated with tobiano coat color in a crossbred horse population through genome-wide SNP association analysis.

In this study, coat color patterns of 142 crossbred horses (Jeju indigenous horse × Thorou...