Cloning of Most Famous Racehorse of All Time is Currently Underway

Equine Science Update

News has emerged that scientists have successfully grown cells containing the DNA of Eclipse, the most famous racehorse of all time. This is the first, and most difficult step to producing a live cloned foal.

Eclipse, born two hundred and fifty years ago, is widely considered to be the greatest Thoroughbred racehorse ever. Unbeaten throughout his racing career from 1769-1770, Eclipse was in different league to his contemporaries and won eight of his races by default – “walk overs” – as no-one would put up a horse to run against him.

His skeleton currently adorns the teaching block named after him at the Royal Veterinary College, London.

A team from the University of London’s Department of Veterinary Embryology have been able to transfer DNA from Eclipse into the cytoplasm of cells from the subcutaneous connective tissue of a donor horse. These fibroblasts have then been proliferated in the lab and have been shown to have remained viable and to contain the replicated Eclipse DNA.

The next stage in the cloning process, which is due to start this month, will be the implantation of the chromosomal tissue into an egg from a donor mare and then the chemical signaling to trigger the egg to start the development into an embryo. After the recombined oocyte has been activated, it is transferred surgically to the oviduct of a recipient mare, which carries the foal to birth. It is possible therefore that a cloned Eclipse foal could be born in early 2015.

Italy’s Laboratory of Reproductive Technology created the world’s first successful horse clone in 2003 by fusing a skin cell from an adult mare with an empty egg but science has developed significantly since then and the commercial opportunities have been close behind. However, the process is not cheap: a syndicate of investors were reported to have spent £104,000 on producing the clone of William Fox-Pitt’s Badminton and Burghley winner, Tamarillo.

After retiring from racing he became a very successful sire. It is likely that there are very few Thoroughbred horses alive today that do not contain a reference to Eclipse somewhere in their bloodlines.

Attempts to recover DNA from his much studied skeleton proved fruitless, but samples of his tail hair which had been woven into the tassel of “The Whip,” the prize of victory in the self-named race, were found to contain sufficient undamaged genetic material for the scientists to work with.

But some in the equestrian community are uneasy, and the RSPCA has stated that it is against cloning. “There’s huge potential for some of the animals involved to suffer unnecessary pain and distress,” said a senior scientific officer at the charity.

A spokesman for the British Equine Veterinary Association said, “Science is progressing at an astonishing rate in equine veterinary medicine and the fact that an Eclipse clone could be born next year, albeit that the rules of racing wouldn’t allow it to compete, is almost unbelievable.”