The foal flutters his eyelids in the dawning hours during his first day of his life. He stands, wobbles around his dam, and finally nurses, showing the vigorous signs of a healthy newborn.

Now that the foal has safely made its way into the world, the breeder starts inventorying exactly what she has in front of her: a colt. Strong Quarter Horse body. Straight legs. Bay. Three small white socks and a broad blaze down the center of his face. One blue eye.

Where did that come from?

No one really knows for sure, says Cherie Lones, director of the Blue Eyed Horse Association (BEHA) in Rapid City, S.D.

"There’s a lot of mystery behind blue eyes in horses," she says. To help gather information on this feature, Lones founded BEHA, a registry to document and track blue-eyed characteristics in horses.

Blue eyes in horses are a relatively uncommon and little-studied occurrence, and the association hopes to change both of those facts.

Equine geneticist and coat-color specialist D. Phillip Sponenberg, DVM, PhD, a professor of pathology and genetics at the Virginia-Maryland Regional School of Veterinary Medicine in Blacksburg, Va., sums up what little is understood about blue eye inheritance in horses this way: "You expect to see them on cremellos and perlinos. Sometimes they occur with white spotting (coat color), and sometimes they occur on dark-colored horses."

Beyond those facts, what is understood about blue-eye inheritance is tied to breeding results and logical guesswork. In this article we’ll look at what is known about eye color in horses.

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