A ‘speed gene’ can be used to identify whether racehorses are better suited to short, middle or long distance races.
The effects of the gene were tested by matching it to the race records of more than 1,700 thoroughbred horses in Britain and Ireland.
Lead author of the study Professor Emmeline Hill, associate professor of Equine Science at UCD, said the research established a clear relationship between the speed gene and a horse’s career earnings by distance.
The gene test enables an accurate prediction of a horse's optimal race distance by examining its DNA. Of the three possible test results, C:C horses are more suited to shorter races, C:T horses to middle distance races and T:T horses to longer distance races.
"This research shows that racehorses overperformed in their optimum distance ranges and underperformed in races for which they were not genetically suited,” she said. “Furthermore, the performance among all Speed Gene types consistently deteriorated as the race distance diverged from the predicted optimal distance."
Professor Hill said a random sampling of horses at each distance would be expected to win the equivalent percentage of available prize-money.
“But the reality is C:C horses disproportionately outperformed in terms of prize-money in races under one mile, C:T horses outperformed in 9 to 15 furlong races, while T:T horses excelled in longer distance races,” she said.
“Some trainers may be missing a trick by competing horses over unsuitable distances. Many still rely on pedigree, which is not an accurate indicator, as middle distance horses can produce both sprinters and stayers. That is the nature of how genetic inheritance can work."
In the study C:C horses represented 71% of three-year-old runners in five to six furlong races. However, these horses won 89% of the available prize money, representing a relative overperformance of 25%.
By contrast 28% of the runners at this distance, 100 horses in total, were C:T type. However, these horses won just 11% of the prize money available, a relative underperformance of 61% and a considerable potential earnings loss for the owners and trainers of those 100 horses.
Professor Hill said the key value of the speed gene test is that it provides a means to accurately predict a horse's optimal race distance as soon as the foal is born, independent of age or training status.
“This enables optimised training and race planning and we have now shown that this will have clear economic benefits for owners and trainers."