Results are starting to come in on the Splash tests

SplashPuzzle

Some of the first test results from the new Splash White tests have started trickling in, and they are proving really interesting. I hope to update the Splash Project page over the weekend, but here is some of what we have learned so far.

As far as I am aware, those horses that have tested positive have all had the SW1 gene. That means the exact nature of the other two versions (SW2 and SW3) is still a mystery.

So far, with really limited results, it does look like in identifying SW1 researchers may have found the gene responsible for Classic Splash. That was the pattern originally described by Klemola in the 1930s. Even more exciting is that the one horse known to have tested as homozygous does have the classic pattern. That horse can be seen at the bottom of the first post on this forum.

Another interesting horse in that group is the homozgyous tobiano. There had been rumors that the KIT gene had been ruled out as a location for Splash White. I had explained why the KIT location was important in limiting the number of color mutations in this previous post, “Location Matters.” If the general rule that was explained there – that a horse should only have two mutations on any given gene – holds true, then finding a horse carrying two KIT mutations and splash white should tells us that splash white is not on KIT. The two tobiano genes would already take the two KIT slots. It is my understanding that there have been at least two horses tested as homozygous for tobiano that also have the Splash White gene.

That opens the door to the idea that there may be a lot more tobianos out there carrying SW1 than we might have previously expected, because  it isn’t an either/or situation. A horse could carry and pass along both patterns. What is also interesting is that tobiano has a way it sometimes skews that creates a dark patch with an odd “point” that drops from the croup. Some of us have long wondered if that might come from Splash, and now a horse with that kind of pattern has tested to be a carrier. It will be interesting to see if more horses with that kind of “point” also test positive, especially those that do not have such splash-like facial markings.

The other big news out of the early results is that there are horses that are coming back with blue eyes that test negative for all three of the Splash genes. It is really too early to know exactly what that means. Obviously more things cause blue eyes than just Classic Splash because they found those two other genes. It may be that there are still more versions, or it may be that one of the many yet-to-be-identified sabino patterns are involved. What we can say is that blue eyes are not caused by just one or two things. The situation is more complex than that. But then if pinto tests have told us anything, it is that it is all more complex than anyone originally thought!

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14 Responses to Results are starting to come in on the Splash tests

  1. Dorothy Robertson January 27, 2012 at 12:29 pm #

    Regarding blue eyes….it has long been held in the stockhorse world that either splash or frame was responsible for blue eyes. If there are horses with blue eyes testing negative for all three of the splash genes…have any of those horses also been OLWS negative? If negative for both splash and OLWS then indeed that would be interesting…either an independent gene for blue (possibly closely related or connected to splash or frame) or other splash genes or possibly sabino contributing….fun stuff.

    • The Equine Tapestry January 27, 2012 at 1:56 pm #

      Yes, some have been OLWS negative.

      If you scroll back through the posts tagged “eye color”, you’ll see some speculation about blue eyes and their causes. I have thought for a while that we probably had more causes than was commonly understood. There are a number of studies on this from the past that raise questions about blue eyes and other patterns. Carol Mulder did a really in-depth accounting of the blue eyes in some of the early Arabian bloodlines, and came up with a few conclusions. I tracked a family in Walking Horses that consistently passed along blue eyes, but had a pattern that did not much resemble Classic Splash. And there are quite a few dominant whites from a variety of breeds that have had blue eyes that did not have evidence of splash in their background. I think it is safe to say that while these tests are adding to what we know about blue eyes, we probably still have a lot yet to learn. :)

  2. Kristin Berkery January 27, 2012 at 12:50 pm #

    Verrrrrrry interesting! I’m enjoying following along as the mystery is uncovered :)

  3. Heather January 27, 2012 at 11:03 pm #

    There is another mare who tested negative for all three forms of splash…that I would have swore was splash! ACCPhotography owns her, she is a chestnut mare with a bald face and a few white legs. She also has frame. She is thought to be an AQHA/APHA mare, her breeding is unknown.

  4. Pauline H January 28, 2012 at 7:34 am #

    It’s indeed interesting to see what the results are from some of the tests. And to see these things after just a handfull of tests makes me wonder just how many surprices we’ll get once more horses are tested!

    As for the Gotland ponies, I sent in two tests two days ago. It might take a while to get the results dues to the shipping, but it’s two rather interesting individuals. Here’s one: http://migrated.ifokus.se/uploads/5f1/5f1964102e433cd083c6543e4539204e/spirello2.jpg and here’s the other: http://uploads.ifokus.se/uploads/0b4/0b4ed2bce8d03243ab9da793acebe9fa/dsc07726.jpg

    • The Equine Tapestry January 28, 2012 at 8:06 am #

      Pauline, you just made my day! I am so tickled that some Gotlands are going to be tested.

      • Pauline H February 7, 2012 at 11:54 am #

        Good news! Of the two horses I sent in tests for – both of them tested SW1/SW1!

        I also know of two more Gotlands that were tested, of which one tested negative and one tested SW1/N. I have asked the owner if she’d like to share any photos, so hopefully she’ll say yes.

      • The Equine Tapestry February 8, 2012 at 12:57 pm #

        That is awesome! Thank you so much for sharing the results!

      • The Equine Tapestry February 8, 2012 at 1:00 pm #

        What is the name of the second Gotland? I just realized that his image didn’t have a name.

  5. Donna Boddie January 28, 2012 at 7:52 am #

    I have sent in a sample for my QH mare with a blue eye to test of Splash. I didn’t think to add in overo but will worry about that later as I am sure she isn’t overo. She doesn’t have any obvious horses in her pedigree to point out Splash apart from Leo a long way back.

  6. Dorothy Robertson February 8, 2012 at 2:39 pm #

    Info on another board says that a Gunner bred horse (APHA/AQHA) has tested positive for SW1/SW2. Poster stated she verified with UCD.

    • The Equine Tapestry February 8, 2012 at 2:52 pm #

      I saw that. I have to imagine that Gunner is either SW1/SW2, or SW2/n, since the information from UCDavis is that the other forms may be lethal.

  7. Pauline H February 9, 2012 at 1:53 pm #

    Couldn’t reply to the other comment, so here we go!

    Apparantly somone was faster than I was, and sent the information to JNFerringo here: http://jnferrigno.deviantart.com/journal/Test-for-Splashed-White-Horses-2-SW1-SW2-horses-279547039 There you have both names and information about them both!

  8. Teresa May 9, 2012 at 10:25 pm #

    Wow I have a double blue eyed mini stud that tests negative for frame. So we have assumed he is splash even though he only has a blaze and coronet for markings. Wish I could have him tested for the splash white gene.