Cloning Barbaro
Posted: Monday, January 29, 2007 8:01 PM by Alan Boyle
Will there ever be another horse like Barbaro? Maybe so, if it were up to cloning researcher Katrin Hinrichs. Theoretically, you could take a tissue sample from the now-dead racehorse, culture some cells and freeze them for future Barbaro clones, she said.
"It just seems to make sense to do that when you have an animal that's genetically valuable," the veterinarian who heads Texas A&M's Equine Embryo Laboratory told me today.
Not that you'd ever put a Barbaro clone in a race. First of all, the rules of thoroughbred racing bar horses produced through cloning, or even through artificial insemination. But there's a more fundamental reason why clones don't make good racers, Hinrichs said.
"This is not a way to produce competitors, because cloning carries along with it so many things that could affect its robustness as a foal. ... If we were to clone Barbaro, that clone would be smaller than Barbaro, maybe not as wide across the chest," she said. The clones would likely lack the environmental factors that turned Barbaro into a champion - such as factors that are passed along from mare to foal during the early stages of pregnancy.
Nevertheless, even though the clone might not be built like a champion racehorse, his sperm would pass along the genes of a champion. And that's how cloned horses would make their mark - as breeders, not racers.
"A clone of Barbaro might not be a good racehorse, but the one thing is that the clone would produce the same foals that Barbaro would have produced," Hinrichs said.
Hinrichs made her mark in the cloning field two years ago, when she and her American and French collaborators produced the first horse ever cloned in the United States. Only one other research group, Texas-based ViaGen, is up and running in the horse cloning race. And this race is more of a marathon than a six-furlong dash. Last year, Texas A&M's group produced just seven cloned foals, while ViaGen produced another five, Hinrichs said.
"We're not exactly burning up the highway here - compared to, say, cattle, where they have dozens of labs working on this throughout the world," she said.
The current policies of the top horse racing associations have served to hold down the commercial interest in cloned horses.
"The main problem is that they can't be registered with any American-type breed registry," Hinrichs explained. "This is what would stop a thoroughbred from racing. But there are areas of competition that are very worthwhile that don't require registration."
For example, Texas A&M's first cloned horse, Paris-Texas, is a genetic copy of Quidam de Revel, one of France's best-known jumping horses and most expensive studs. Hinrichs said Paris-Texas' progeny could well compete in future show-jumping events, carrying Quidam's champion genes into the race. ViaGen, meanwhile, has been cloning cutting horses as well as steeds built for other equine sports.
Winning competitions isn't the only reason for researching animal cloning, of course. Hinrichs said genetic material preserved at facilities such as the Frozen Zoo in San Diego could someday give a boost to endangered species. "That offers an amazing resource for genes that are [otherwise] lost forever," she said.
It's not yet clear whether the appropriate samples were taken from Barbaro before he died. But considering how much attention the topics of DNA analysis and cloning have gotten in the past few years, I'd have to think there's a suitable sampling of Barbaro's tissue already sitting in a flask of liquid nitrogen somewhere.
Even though clones are currently barred from thoroughbred racing, Hinrichs said it still might be worth leaving your options open. Who knows? Maybe the rules will change in 50,000 years - which Hinrichs said is the estimated half-life for the potency of frozen sperm samples.
Update for Jan. 31, 10:30 p.m. ET: The surgeon who treated Barbaro says that no sperm was taken from the horse before he was euthanized. Dean Richardson acknowledged that future fertility would have been a bonus, but "we only were interested in saving his life." No word about tissue samples, though.
Update for Feb. 2, 9:30 p.m. ET: This story in the New York Daily News says Barbaro's owners have denied taking any sperm from Barbaro, or saving any DNA for cloning. Actually, just having a DNA sample would be insufficient for cloning, anyway. You'd need to preserve live cells. But I would side with Hinrichs on this matter: It just seems to make sense nowadays to set aside tissue, or at least DNA, from any genetically significant specimen.
I know that sounds a little bit like the equine equivalent of "They Saved Hitler's Brain." And I know that the rules of thoroughbred racing currently rule out clones or artificially bred animals. But when we're talking about creatures worth millions of dollars, I don't see the harm in preserving a little bit of genetic posterity, for research purposes if for no other reason.
