All Thoroughbred Racehorses Share A Single Ancestor

From Secretariat to Seabiscuit, it turns out that all thoroughbred race horses were all related. They shared a single ancestor in the mid 17th century, whose "speed gene" was a genetic aberration:

Emmeline Hill of University College Dublin led a team that analyzed DNA in 593 horses from 22 modern breeds, as well as museum specimens from 12 historically famous stallions. Modern genetics have become sophisticated enough that they could tell, with considerable precision, what the horses had in common.

"The results show that the 'speed gene' entered the thoroughbred from a single founder, which was most likely a British mare about 300 years ago when local British horse types were the pre-eminent racing horses, prior to the formal foundation of the thoroughbred racehorse," said Hill in a prepared statement.

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