Edinburgh University study concludes best genes don't necessarily have highest price tag

Alastair Wilson and Andrew Rambaut of the Institute of Evolutionary Biology at the University of Edinburgh have published a study of the relationship between stallion fees and the success of the stallion's progeny, measured by lifetime earnings.

The authors used data on over 4,000 thoroughbreds to perform quantitative genetic analyses within an animal model framework.

They found that while there are good genes to be bought, a stallion's fees are not an honest signal of his genetic quality and are a poor predictor of a foal's prize winning potential.

Up to 90% of of a racehore's performance is attributable to environmental factors such as training and jockey's skills, with the remaining 10% linked to pedigree.

Alastair Wilson said: "The offspring of expensive stallions might tend to win more money, but not necessarily because they have inherited the best genes.

"It is likely that those breeders best able to pay high stud fees are also those who are able to spend more on care of the horse, how it is trained and who rides it - all of which will contribute more to how much it will win.

"Of course, if every breeder is spending lots on the care of the horse, then the difference between winning or losing will come to smaller details, such as who the parents are.

"So picking the right genes can give an edge, but it's by no means clear that the best genes come with the highest price tag."

The full article may be obtained from the Biology Letters website