Intelligence appears to be a key element in the success of harness racing horses, fresh research suggests.
Several genes related to intelligence, energy metabolism, and immune function have been identified in a just-published Scandinavian study of potential candidate genes for racing success among trotters in Scandinavia.
“Knowing where, why, and how genes and athletic prowess intersect in a racehorse has long been the goal of countless researchers, veterinarians, breeders, trainers, and owners,” Brandon Velie and his colleagues reported in the journal BMC Genetics.
“While great strides in this area have recently been made for gallop racing horses, similar advancements for harness racing horses have been limited.”
In the study, based at the Swedish University of Agricultural Sciences, researchers set out to explore the genetic background for athletic prowess in Norwegian-Swedish Coldblooded Trotters.
Genetic material was analysed from 613 horses.
This work revealed a total of 32 single-nucleotide polymorphisms, or SNPs, of interest. SNPs are the most common type of genetic variation. Each SNP represents a difference in a single DNA building block, called a nucleotide.
Of the SNPs 32 of interest, nine demonstrated genome-wide significance and 13 were found residing in genes.
In all, eight genes were suggested as strong candidates for harness racing success – GRIN2B, DOCK8, ATP7B, KCNRG, PIP5K1B, PDE3A, INPP5D and SOX5.
These genes are variously involved in neurological, metabolic, and musculoskeletal regulation, which the researchers said pointed to the complexity of harness racing success.
“Apart from the physiological requirements needed for a harness racing horse to be successful, the results of the current study also advocate learning ability and memory as important elements for harness racing success,” they said.
“Further exploration into the mental capacity required for a horse to achieve racing success is likely warranted.”
The authors noted that, regardless of horse-racing discipline, speed, or perhaps more appropriately, unparalleled speed, is the “holy grail” of almost every horse owner, trainer, and breeder.
“However, speed alone does not necessarily equate to success on the racecourse. The manner in which a horse demonstrates speed is critical to its racing success.
“For example, while the ability to gallop fast may result in a champion Thoroughbred or Quarter Horse, the same ability in a Standardbred or Coldblooded Trotter is of little value.
In Standardbred and Coldblooded Trotter racing, horses undoubtedly require speed, but galloping, a four-beat gait, results in disqualification.
“Thus, speed in these breeds must be demonstrated at the trot. Consequently, racing success in Standardbreds, Coldblooded Trotters and other harness racing breeds depends not on an individual’s capacity for speed, but on an individual’s capacity for speed in a specific gait.”
While significant genomic resources have been applied in studies attempting to map speed and racing success in Thoroughbreds and Quarter horses, their applicability to harness racing breeds has been limited.
Despite the fact that harness racing success is economically important to the global equine industry, genome scans for performance mostly target Thoroughbreds and sport horses.
Conversely, most studies involving harness racing breeds tend to focus on detecting genes underlying certain conditions and diseases.
“While disease studies are undoubtedly important for improved animal well-being, a greater awareness of the genes, and by extension the underlying biological mechanisms, involved in racing success are also likely to prove highly valuable.”
It was amid this background that the researchers undertook their genome-wide association study.
“Apart from the physical attributes required to achieve racing success, multiple candidate genes identified in the current study also advocate learning ability and memory as critical to success.
“However, further analyses of these genes based on additional genetic and functional studies are required to explore this notion in greater detail.”
The full study team comprised Brandon Velie, Kim Jäderkvist Fegraeus, Marina Solé, Maria Rosengren and Gabriella Lindgren, all with the Swedish University of Agricultural Sciences; Carl-Fredrik Ihler and Eric Strand, with the Norwegian School of Veterinary Science; and Knut Røed, from the Norwegian University of Life Sciences.
A genome-wide association study for harness racing success in the Norwegian-Swedish coldblooded trotter reveals genes for learning and energy metabolism
Brandon D. Velie, Kim Jäderkvist Fegraeus, Marina Solé, Maria K. Rosengren, Knut H. Røed, Carl-Fredrik Ihler, Eric Strand and Gabriella Lindgren.
BMC Genetics 2018 19:80 https://doi.org/10.1186/s12863-018-0670-3