Calvin Borel rode Super Saver to win the 2010 Kentucky Derby.Image: Churchill Downs
When the Kentucky Derby winner crosses the finish line in front of 160,000 roaring spectators on May 5, there's a good chance it will have two copies of a gene that makes a horse a sprinter.
The so-called speed gene, which several laboratories say determines whether a horse prefers a short sprint, a marathon or something in between, is just one of the genetic markers identified in the search for the roots of elite performance in thoroughbreds. Now the race is on among five or six commercial laboratories to convince thoroughbred breeders and buyers that testing for this gene and other markers is the road to the Triple Crown. In the meantime, the geneticists behind these companies scramble to lay claim to the best markers for athletic traits. Major thoroughbred farms are signing up horses for testing, even though some say they're not sure what the results mean.