Saturday, December 26, 2009

White wonder

Something kind of wonderful happened in Japan about 18 months ago, but, so far as I can tell it has completely escaped the notice of the American media. If I've missed something, let me know, but I've Googled it and searched on the appropriate websites, and can't find any coverage in the American racing press.

In June of 2008 at Kawasaki (yeah, that's right) Racecourse, a filly named Yukichan won a race called the Kanto Oaks. Never heard of it? Well neither had I until I ran across Yukichan, but it qualifies both for black type and as a stakes race according to international cataloging rules.

What makes this kind of wonderful is that Yukichan is white. If you click on the two links above you'll see that not only is she pure white, but quite an attractive filly who moves like a good horse both on both dirt and turf. She totally dominated her opposition in the Kanto Oaks (which perhaps would be on the level of a winter stakes at Turfway Park), winning easily by eight lengths under great Japanese jockey Yutaka Take, who barely moved on her. Yukichan has placed in two other, better, stakes.

I'm pretty sure this is the first time a Thoroughbred registered as white has won a stakes race anywhere in the world. Now personally, I've never been particularly enamored with white Thoroughbreds since, genetically, coat color is not an indicator of anything except coat color, but some folks just go absolutely gaga over them, so I'm surprised that no one over here seems to have picked up on this pretty filly's accomplishments.

"Yuki" means snow in Japanese and "chan" is an endearment often tacked onto Japanese names, so Yukichan would mean something like Snow Darling in English, which is appropriate enough.

The most interesting question about Yukichan is how she came to be white in the first place. Her sire, Kurofune, by French Deputy, was a very high-class racehorse, winning six of 10 starts, including the Japan Cup Dirt-G1 on dirt and the NHK Mile Cup-G1 on turf, which earned him champion 3yo colt honors in 2001. Kurofune's stud record is spotty, with only six stakes winners from about 500 foals, but two of them are Japanese champions.

Kurofune's color is classified by the Jockey Club's misleading "gray or roan" designation. Don't get me started, but since gray and roan coat colors are caused by different alleles of the color genes (true roan is very rare in the Thoroughbred), that designation is even more ridiculous than "dark bay or brown".

Anyway, Kurofune's coat color, whether he is a true gray or a true roan, also doesn't have anything directly to do with Yukichan being white. If my understanding of coat color genetics is correct, Kurofune has to be a carrier of the overo gene to be able to sire white offspring, and whether he's gray or not has nothing to do with that. Kurofune's coat color (almost certainly gray) comes from his dam, Blue Avenue, whose dam, Eliza Blue was a gray by the gray horse Icecapade. No sign of white horses there, on the surface at least.

Yukichan's dam, Shirayyukihime ("white snow" in Japanese), on the other hand, is also registered as white. The question is, how the hell did that happen? Her sire was the immortal Sunday Silence, whom the Jockey Club insisted was dark bay or brown, though anyone with normal human color perception would call him black. Not only that, but Yukichan's year-older full brother White Vessel is also white. He has won 3 of 13 starts, but is not a stakes horse.

Shirayukihime's dam, Wave Wind, by the bay Topsider, was also registered as dark bay or brown. The author is intimately familiar with Yukichan's third dam Storm and Sunshine, a lovely, feminine version of her sire Star de Naskra, a horse who raced for and stood at Pillar Stud while I was general manager there. Storm and Sunshine was a very good filly, winning 10 of 19 starts, including the Test-G2 and Post-Deb-G3.

Storm and Sunshine was a solid, mahogany bay, as was Star de Naskra, but her broodmare sire Drone was gray--for what that's worth.

Obviously the overo gene that causes white horses can hide for generations, but often it shows up in modified form somewhere in the horse's pedigree as particularly extensive or unusual white markings. Obviously I don't know exactly what every horse in Yukichan's pedigree looked like, but if there's any sign of white before Shirayukihime popped up, it certainly isn't obvious.

And of course it really doesn't matter. Yukichan is a lovely filly with at least a modicum of talent, and a pretty good pedigree. She would be an asset in most broodmare bands, regardless of color.


  1. Wonder if there might be a mutation that occurred with Shirayukihime similar to whatever went on with the splash-spotted stallion Puchalingui?
    At least, the JC decided he was mutant, rather than a case of suppressed color....

  2. Shirayukihime was white, as you noted. But she had 3 white foals: White Vessel and Yukichan by Kurofune, AND Shirokun, by the Nureyev horse Black Hawk.

    Yukichan also won a race on 12/9/2009.

  3. Thanks Sid...That's actually the race that brought her to my attention, but now I can't figure out where I saw it. I thought it was on the stakes results on, but there's nothing there now....and EquineLine doesn't list a start for that date yet, which is unusual, unless it was NRA racing there. It's a mystery.

  4. The first US registered white foal, White Beauty, was out of a "dark bay" (read "black") mare. Maybe that color smothers any expression of overo, so that when it crops up in the offspring it is a surprise.

    The reason white horses draw attention is that they are rare and stand out in a group of their peers, like a bright chestnut in a harness race, or a bay Lippizanner. They are easier to follow on the track, too. Greys who have gone quickly toward near-white can get similar attention; remember Vigors, "the White Tornado?"

    Ann Ferland

  5. Great article, beautiful video. LOVE Sunday Silence. Leave it to him!!

    Even more, thanks for the Urban Sea profile. I wish their were more photos of her and that her darn Arc was on youtube.

  6. They're not "Overo", "Sabino", or any other extreme Pinto. They are what's termed "Dominant White". Puchiluingi was one (W5), the Patchen's are another (W2). Each family seems to be it's own distinct mutation of the KiT gene though they all tend to look White (granted some more or less than others). GQ Santana is the founder of DW in the Quarter Horse, it also exists in Arab, Camarillo White, Shetlands, and numerous other breeds. Note that Yukichan is pictured as part of the Wikipedia page on Dominant White.

    Oddly enough, Native Dancer has actually been implicated in "funky TB color genes" (for lack of better), Halo is being researched, The Tetrarch is also implicated, All three are in Shirayukihme's pedigree.

    The only true Roan TB's are descendants of Catch A Bird (NZ). A random mutation gave the Rn gene to his foals and they are managing to breed more Roans from them in AUS and NZ. All other TB's labeleld "roan" are either Grey or mislabeled.

  7. is about the white TB in the US. They are becoming more common(along with the occasional "painted" TB).

  8. It could very well be a mutation of sabino to Dominant White, or an extreme sabino. The Northern Dancer line is full of sabinos. The pure whites always start as a mutation, and then they pass it on. However, any time there are blue eyes, that indicates overo or splash genes at work, too. There are at least seven different mutations causing Dominant White, and at least four of them have been recorded in Thoroughbreds. Here is an article I did on pinto racing Thoroughbreds, and a follow-up on dominant whites is coming in the next day or so.