Genomic diversity and selection in the racing greyhound of Great Britain

The Greyhound, originally used for hunting, has been selected for
competitive racing. Here, we present the first comprehensive population
genomic analysis of racing Greyhounds (n=54) in the context of 14 other
dog breeds (n=352) using 473K SNP genotypes. Inbreeding in the Greyhound
(FROH = 0.47) was higher than most other breeds, reflecting positive
selection for athletic traits but also raising concerns about potential
health impacts. Although very long runs of homozygosity (ROH) were less
common in the Greyhound than some breeds, large ROH islands suggest that
selection for advantageous traits is relatively recent. Genomic regions
under strong selection overlapped with ROH islands on CFA2, CFA4, CFA9,
CFA10, CFA25, and CFA28, and contained candidate genes with marked allele
frequency differences relative to other breeds. Notably, the strongest
selection signal on CFA25 overlapped with the longest ROH island,
encompassing the SLC46A3, POLR1D, FLT3, SLC7A1, MTUS2, LHFPL6, USPL1, and
USP12 genes that have biological functions in vision, craniofacial
morphology, neurological adaptability, and skeletal, cardiac, and muscle
biology, implicating them in shaping the Greyhound’s morphological and
athletic phenotype. This study provides insights into the population
genetic structure and selection pressures in the racing Greyhound,
identifying key genomic regions and candidate genes that may underlie
racing capabilities. Importantly for animal welfare, these results provide
a framework for managing inbreeding to optimise health and performance for
future generations.