An important set of genes associated with successful racehorses has been identified by an international research team.
Scientists from Asia, Europe, North America and Irish equine science company Plusvital compared the genomes of Thoroughbred, Arabian and Mongolian racehorses with horses bred for other recreational sports, and were able to identify a set of genes that play important roles in muscle, metabolism and neurobiology.
These genes were found to be distinctly different in racehorses, and were common to all racing breeds compared to those of non-racing breeds.
“Since the discovery of ‘Speed Gene’ in 2009, we have generated genetic data on thousands of Thoroughbreds and horses of other breeds,” said University College Dublin Professor Emilyn Hill, lead scientist on the project and head of science at Plusvital.
This is the first time this set of genes has been linked to the breed’s racing success. Two genes had previously been identified for performance in Thoroughbreds and Arabians, but our approach was to ask what genes are common to all racing breeds and different from non-racing breeds.
“The very large number of horse breeds that have been developed over the past hundreds of years all over the world have been carefully shaped by selective breeding for the different qualities desired by breeders. This has resulted in tall horses, small horses, powerful draft horses, useful riding horses and racehorses A quick.
“We discovered a set of genes that are common to racehorses, but not all horses within a racehorse have an advantageous gene copy, so these results will be useful for identifying individuals within a breed that are best suited for racing or for breeding.”
Co-author Professor David Macchio at UCLA commented: “Although racing is a multifactorial trait, management and training have a significant impact on the success of a racehorse, this study provides good evidence for high-impact genes that make up the trait.” Racing in numbers of horses.
The research, published in Communications Biology, an open-access journal from Nature, involved a collection of hair samples from 100 horses owned by the champion Ajnai Sharga Horse Racing Team at their breeding farm in Khentii Province, Mongolia, the birthplace of Genghis Khan.
Using DNA from these Mongolian racehorses, along with those of Thoroughbred racehorses and Arabian horses, the scientists compared the genomes of these breeds with those of 21 other non-racing breeds, such as Clydesdale, Connemara Pony, Hanoverian, Morgan, Norwegian Fjord, Dahan, Shetland, Shire, They identified seven essential genes for racing.
Among the top genes was NTM, which is involved in brain development and affects learning and memory. This gene was chosen during the horse domestication process, and in thoroughbred race horses it affects whether or not a horse races.
“This finding suggests that the nervous systems of horses disturbed by natural and artificial selection associated with domestication may interfere with the adaptive traits required for racing,” said Professor Macchio.
Dr Haig Han, another collaborator on the project and first author of the paper, added: “Testing of these variants in new cohorts of hundreds of horses of both racing and non-racing breeds identified seven essential genes for racing. These genes have roles in muscle, metabolism, neurobiological functions, It is fundamental to racing ability among horse breeds.”
The researchers used gene expression data from skeletal muscles from thoroughbred horses to check whether the genes they identified are involved in muscle response to exercise and training.
“By combining the two different datasets, we fine-tuned the list of racing genes to those most biologically relevant to racing. One of these genes was MYLK2 which is required for muscle contraction. In humans, MYLK2 is associated with exercise-induced muscle damage,” said Professor Hill.
This research was supported by the National Key R&D Program of China; National Natural Science Foundation of China; Science Foundation Ireland; US National Institutes of Health; The Cirencester Trust of the Royal Agricultural University; and Plusvital Ltd.
Conducted in collaboration with the UCD School of Agriculture and Food Science and the UCD Conway Institute, Ireland; Royal Agricultural University, UK; Inner Mongolia Agricultural University, China; Mongolian Academy of Sciences, Ajnai Sharga Horse Racing Team, Mongolian University of Science and Technology, and Mongolian National University of Medical Sciences, Mongolia; Institute of Agricultural Sciences, Switzerland; Caltech and Saban Research Institute, Children’s Hospital Los Angeles, USA; and Plusvital Ltd.
Plusvital has been a pioneer in equine science since its inception in 1975, growing out of the world-famous Irish horse racing and sport tradition.
In 2015 Plusvital acquired Equinom, a UCD subsidiary co-founded by Professor Hill, which now offers horses DNA decomposition tests to predict their racing performance potential. Plusvital’s clients include the leading trainers, owners and breeders in all major Thoroughbred regions around the world.