Winning Colors is NOT a roan!
or, why there is no such thing as a true roan TB*
*(with one tiny exception)
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Every year when the Derby rolls around, the racing pundits like to comment about how Winning Colors is the only roan to have ever won the Derby. They are dead wrong. No roan horse has ever won the Derby because roan does not exist in the TB gene pool. Winning Colors is a grey, just like Giacomo, Monarchos, Silver Charm, Gato Del Sol, Spectacular Bid, Decidedly, and Determine. Before we go any farther, let's examine the differences, both genetic and in physical appearance, between grey and roan. GREY: Grey is a dominant gene meaning that if it is present in a horse's genetic make-up, it will be expressed in the coat. This also means that every grey horse will have at least one grey parent. The color can therefore be traced back through the pedigree by following the direct line of grey horses to the earliest known ancestors of the horse. The grey gene is a color modifier rather than a simple color like black or chestnut. All grey horses are born as their base color, be it bay, chestnut, or palomino. Most will have hints of the grey gene being present at birth in the form of grey rings or "goggles" around their eyes. As they age, their coat will slowly lighten and dapple and eventually turn almost white in old age. Horses grey out at different rates. Some are nearly white by age three; others don't reach that point til they are into their teens. Pictured below is Unbridled's Song at three points in his life, showing how the grey gene changes a horse's coat as it ages. |
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| ROAN: Roan is also a dominant gene (most horse color genes are), meaning that if it is present in a horse's genetic make-up, it will be expressed in the coat. This means that every roan horse will have at least one roan parent. The color can therefore be traced back through the pedigree by following the direct line of roan horses to the earliest known ancestors of the horse. The roan gene creates a pattern of white hairs that are sprinkled throughout the horse's coat except on the head, legs, mane, and tail. Roan horses are born looking roan and remain this color throughout their lives. The roan gene is found primarily in stock, gaited, and draft breeds. See the pix below for examples of roans. From left column to right column, a bay roan shown as a foal and as an adult, a chestnut roan foal and adult, and a black roan foal and adult. |
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| So now that the difference between grey and roan is clear, let's have a look at Winning Colors. Here she is pictured at age three winning the Derby (left) and in old age (right). It's obvious that she is in fact a grey. |
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So where does the confusion between grey and roan in the TB breed come from? From the American Jockey Club. Here is their definition of the two colors: "Gray: The majority of the coat of the horse is a mixture of black and white hairs. The mane, tail and legs may be either black or gray, unless white markings are present. Roan: The majority of the coat of the horse is a mixture of red and white hairs or brown and white hairs. The mane, tail and legs may be black, chestnut or roan, unless white markings are present." What that means in a nutshell is that the JC terms black-based greys to be greys and bay- or chestnut-based greys to be roans. It's a matter of semantics, technically, but it's confusing to those familiar with color genetics. Most people understand there is a definite genetic and physical difference between grey and roan. The JC is happy just to lump them together despite the fact that true roan is not found in the breed. |
| *The Catch A Bird Exception: The only exception to the statement that there are no true, dark-headed roan TBs has cropped up very recently. In 1982, a very unusually marked Thoroughbred was born in Australia named Catch A Bird. He looks like a bay horse with white brindling, the opposite of the dark lines seen on "normal" brindles. Stranger still, as a stallion, Catch A Bird has produced four offspring that appear to be true, dark-headed roans, indicating that Catch A Bird carries a one-time genetic mutation that has produced roan. As far as I know, none of the 4 "roan" foals, Odd Colours (1992 mare), Slip Catch (1993 mare), Goldhill Park (1994 horse), and Red Noble (1996 gelding), have been tested to see if they carry the roan gene, but they certainly exhibit the typical roan phenotype. Please note that these four horses appear to be the only true roan TBs in existence. All other horses registered as roan or grey/roan worldwide are actually greys. |
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Pictured at left is Catch A Bird, who looks like a brindle, except with white striping instead of dark striping. With regular brindles, the dark stripes are caused by the sooty hairs in the coat being arranged into lines, rather than being randomly scattered. I can't help but wonder if something similar might be happening to Catch A Bird's coat. I suspect he carries the sabino gene, and perhaps rabicano? Either gene can cause white flecks in the coat that mimic true roan---perhaps Catch A Bird does exhibit one of these patterns and the white hairs have simply been organized into lines like a brindle. That would suggest that there is a relationship between sabino (and/or rabicano) and roan, especially since Catch A Bird has produced roan offspring, but what that relationship is, if there is one, has not yet been determined. |
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