By Blake Jackson
A study led by the University of Kentucky has shed light on the genetic landscape of North American Thoroughbred horses. Utilizing whole-genome sequencing data from 185 horses born between 1965 and 2020, researchers investigated genetic diversity and inbreeding within the breed.
The study, published in Scientific Reports, compared two groups of horses: those born between 1965 and 1986 and those born between 2000 and 2020.
While the study found a slight increase in inbreeding in the younger group, it also revealed a 10% increase in the frequency of a genetic variant linked to sprinting ability, reflecting a shift in breeding priorities towards shorter races.
“The impetus for this study was to quantify the extent of genetic variation and inbreeding in Thoroughbreds,” said Ernest Bailey, professor in the Maxwell H. Gluck Equine Research Center at Martin-Gatton CAFE and the study’s lead author. “By identifying trends, we’re equipping breeders with the data needed to make informed choices that preserve the breed’s health and performance.”
“Selective breeding focuses on enhancing desirable traits like speed and stamina, but it can also increase the risk of amplifying harmful genetic variants,” said Jessica Petersen, associate professor at the University of Nebraska-Lincoln Department of Animal Science. “Our data gives breeders a clearer roadmap and tools to navigate these challenges.”
The study highlights the importance of utilizing genomic data to monitor and manage genetic diversity within the Thoroughbred breed.
By identifying and mitigating potential risks, breeders can ensure the long-term health and athletic performance of these iconic horses.
“The data shows that breeders have done a good job,” Bailey said. “Genomic tools make this clear at the DNA level but are unlikely to replace a breeder’s insights and intuition in the quest to create a better racehorse. However, these are precisely the tools we need to monitor and respond to hereditary problems that may arise.”
Photo Credit: gettyimages-somogyvari
Categories: Kentucky, Education, Livestock