This five year-old Saddlebred mare was recently listed on Craigslist, and her owner has allowed me to use her photos here. Longtime readers of the blog might remember the unusual greys that were discussed here (“Ponies Don’t Read”) and here (“Another Unusual Grey”). When I saw those horses, they reminded me of some a handful of unusual roaned Morgans that I had seen, though they were definitely not greys. This mare, however, is a lot more like the Morgans. You can see their pictures on the Morgan Colors site. The one most like this mare can be seen here:
Sleepys Select Rose
Sleepys Select Rose (winter coat)

I have seen a handful of other horses a bit like this one, all with roaning on the body that tends towards dappling or reverse dappling, dark legs and white on the face. I’ve tended to categorize them as some kind of odd sabino roan, simply because right now just about anything that produces roaning and white markings gets lumped into that category. Of the existing categories, it was the closest match. But it is much more likely that what we call “sabino” is a lot of different things. What seems to be true of horses like this mare is that they are usually connected – when their backgrounds can be determined, at least – to sabino roan families of a certain visual type. Those are horses that look quite a lot like true roans, only they are more uniformly roaned over their entire body. They usually have dark legs and some white on the front of the face, rather than the wrap-around blaze typical of ‘flashy white’ sabinos.

I have inquired about this particular mare’s background, to see if there are similar connections, and will post any information I receive. In the meantime, if readers have horses with extensive roaning and white on the face but not the legs, but that are not true, dark-headed roans, I would love to see them.

UPDATE: The mare’s name is Wing’s Sable Sky. Her owner is in the process of getting larger pictures taken, so hopefully I can share those in the near future.

I am a big believer in the benefit of grouping images of horses of a specific color or pattern as a way to develop a solid mental image of the different colors. For those of us that paint horses, it is the single best way to develop your eye. Back before there were many horse sites on the internet, I kept clipping files. The down side was that my ability to collect images outpaced my ability to clip them from magazines and sort them into scrapbooks. I still have boxes of unsorted images from that time! With the computer, it was much easier to sort images into folders and I assembled hundreds of thousands of references.

What I have not been able to do is share them. As anyone who has followed this blog for a while knows, I am a stickler for intellectual property rights. I stick with pictures that I have taken, that are in the public domain, or that I have been given specific permission to use. I would love to share my sorted images, but I do not own most of them. Keeping a library of images for personal reference is quite different from posting those same images on a public website. Which brings me to Pinterest.

Pinterest has been described as a virtual corkboard, but really it is a social media site for the sharing of links. The site allows users to assemble groupings of links by topic, and then uses a thumbnail as a visual for that link. Most people use it to share images of products and ideas that they like. For me, I saw it as a great way to put together some color sorting files that linked directly to the source (ie., the owner or farm that had the horse), while still giving an overview of the range in a particular color or pattern. The image above comes from a board I started with images of homozygous tobianos. What I was specifically interested in was the range of face markings, because I had noted that even in breeds not inclined to face markings, the homozygous horses often had a fairly high level of white on the face. Looking at a lot of them, from a lot of breeds, might be helpful to see any trends. I also have a board for tested SW1 splashes, tested Sb1 sabinos, and the Bald Eagle line that has tested negative for splash. Eventually I hope to add more boards for other colors and characteristics, because I think this might be a particularly good way to share visual information.

For those that are not currently using Pinterest, here is a good overview of how the site works. You’ll notice that you do have to request an invite, since the service is actually still in Beta mode. This can take a few days, in my experience.

(Oh, and I must apologize that I have not found a way to separate out my personal Pinterest boards from the horse color ones. So beware that there are boards for recipes and craft ideas and pretty artwork all completely unrelated to the topic at hand!)

More information keeps coming in from the new Splashed White tests being offered by UC Davis. Horses that have tested positive for the second version of the splash mutation (SW2) have been identified. Only a few have been made public,  but links to those have been added to the Splashed White Project page. So far the positive results have been consistent with the rumor that the SW2 mutation is present in the Gunner line of Paint Horses.

For many, the biggest surprises with the new tests have been how many horses have tested negative. I had suspected that might happen, because I knew that blue eyes were not a reliable indicator that a horse could or would produce the classic pattern. Finding horses without the classic pattern testing negative was something I expected. What I didn’t expect at all was to find horses that tested negative with the classic pattern. And now that is exactly what has happened.

Those that have read Jeanette Gower’s book Horse Color Explained may remember the Australian splash line of Bald Eagle. Several horses from this family are pictured in the book, and more can be seen at the Dunsplashin Stud website. They have classic splash patterns, but so far they have all tested negative for all three genes. What is even more interesting is that, speaking to breeders, it is clear that this particular family show this pattern with just one copy of their gene. Unlike the SW1 mutation, which presents as a classic pattern when it is homozygous, the Bald Eagle horses have the classic pattern – and produce it – with only one gene. One breeder stated that it was thought that the color was homozygous lethal, which is what is thought to be true of SW2 and SW3.

With each new pattern test, it becomes more clear that there are a lot more pattern mutations that previously understood. Because the Bald Eagle line is a sizable family, it seems likely that their mutation – which may be unique to them – will be identified in time. But the discovery that they look so much like the SW1 horses, yet have some other mutation, is another sign that we probably have a lot more patterns than was previously thought, and a lot of them probably look a lot alike.

The last few posts about silver in horses, and merle in dogs, dealt with mutations that alter black pigment without changing red pigment. Those two pigments – red and black – are pretty straightforward in horses. In dogs, though, the term “red” can lead to confusion.

That is because red is used in some breeds, like Australian Shepherds and Dobermans, to refer to what is really an alternate form of black pigment. The same color is sometimes called chocolate (Labradors, Cocker Spaniels), liver (English Setters, Pointers), or brown (Newfoundlands). Although they can appear red-brown in color, the pigment involved is a form of black rather than red. That is why a brown-and-tan dog will have two different shades of red-brown on their body. The brown-and-tan Kelpie pictured above is a good example of this. The darker areas of his coat correspond with the areas you would expect to be black on a black-and-tan dog, while the brighter, copper areas are the places you would expect to be tan. That’s because he carries the mutation that changes the black pigment (called eumelanin) to brown. Because red pigment (called pheomelanin) is not changed by the brown (b) mutation, his copper markings stay the same color. Were this dog not carrying two recessive brown genes (bb), he would be the more familiar black-and-tan.

Red merle are the same kind of color as the Kelpie, only with the merle gene added. Here is a red merle Catahoula Leopard.

Like the Kelpie, genetically he is a black-and-tan dog with the recessive brown (bb) mutation. He also has the merle mutation, which has merled the brown areas (which have a black pigment, or eumelanin, base) but left the tan (which have red pigment, or pheomelanin) alone.

The brown mutation also alters the pigment in the nose, paw pads, lips and eyes, so that the dog takes on a fairly monochromatic brown appearance. Here is a darker brown German Wirehaired Pointer showing how the nose leather is changed. The dog behind him, although somewhat out of focus, shows that the lips are changed as well.

Brown dogs can vary a good bit when it comes to shade. Some are redder than others, while some are a lot closer to black. With darker brown dogs, like this Dalmation and this German Shorthair, it is perhaps easier to imagine that the brown color is really an alteration of black.

So far, all the dogs posted have been genetically black (or black-and-tan) with the brown mutation. Brown, unlike the silver dilution in horses, does change genetically red dogs, too. It doesn’t change their fur, which is red, but it does change their noses, paw pads, lips and eyes. The extreme piebald Ibizan Hound posted a few days ago is a red dog with the brown dilution.

See how his patches are more similar in color to the tan markings on the brown-and-tan dogs? That is red pigmented fur. His nose, lips and area around his eyes are pinkish because the brown (bb) changed what would normally be black to brown. Nova Scotia Duck Tollers are another breed that is genetically red with the brown mutation. They also have pinkish-brown leathers and paler eyes.

Contrast the nose and eyes with the typical Golden Retriever, and that is how brown changes a red-pigmented dog.

And finally, one more bit that tends to cause confusion with the term red in dogs. The Golden Retriever pictured above is a genetically red dog, but most people would not readily call that color red, either. Most genetically red dogs are actually yellow in appearance. That is why, when speaking of dogs, pheomelanin is sometimes called “red/yellow” pigment. In horses, that is not typically used. There diluted red often does look yellow, but that is not common enough that the term needs to be added. In dogs it can help to clarify what it meant by red – especially given the confusion with brown.

(The Kelpie, Catahoula and Golden Retriever pictures are all courtesy of Wikimedia Commons.)

The recent posts on eye defects in dogs reminds me that I meant to share a recent paper on eye defects in silver horses. The issue of eye defects first came to light within the Rocky Mountain Horse breed, where it was initially called Anterior Segment Dysgenesis (ASD). That name was recently discarded in favor of Multiple Congenital Ocular Anomalies (MCOA).

Since its discovery, questions remained about whether or not MCOA was directly linked to the silver dilution, or if it was a more recent mutation tied to one of the Rocky Mountain founders. The recent study, “Multiple congenital ocular anomalies in Icelandic horses“, tied the issue directly to the silver mutation.

In this study we have shown that the MCOA syndrome is segregating with the PMEL17 mutation in the Icelandic Horse population. This makes the hypothesis that the MCOA mutation has recently arisen unlikely.

The Icelandic population is significant because it has been isolated from other domestic horses since 982 AD. If silver Icelandics have the same problem as silver Rocky Mountain Horses, then it is far more likely that the silver mutation is involved.

One of the things that makes this interesting is that the silver dilution – which is linked to eye defects in horses – occurs in the same location as the merling gene in dogs. Both are  PMEL17 (SILV) mutations. Both also dilute black, but not red, pigment. Those are interesting parallels between two colors that have such a visually different appearance.

In the previous post, defects in the eyes were used to help identify a homozygous merle. That is often a strong indicator, but there is one situation where that is not always helpful. Collies, and some of the closely related breeds, have a number of issues with their eyes that are unrelated to the merle gene. Compare the normal eyes of the merle Shetland Sheepdog, above, to the eyes on the merle Rough Collie below.

Like the Great Dane in the previous post, this dog has an eye that appears to be too small and set incorrectly. Her left eye, which is blue, also has a distorted pupil similar to the one seen on the Dane. It is more obvious when viewed from the front.

Although it might look like she is looking to the side in this shot, her pupil actually skewed over toward that corner, giving her a cross-eyed look.

She is not a double-merle. Her pattern is typical for a single merle with moderate white irish patterning. Whatever is wrong with her eyes, it is probably separate from her merle coloring. Her one blue eye makes the problem more noticeable, but chances are she would have had issues whatever color she happened to be.

And that is why distortions in the eyes on collie breeds are not necessarily proof that the dog is homozygous for merle. Fortunately for identification purposes, most double-merle Collies are quite dramatically white so they are unlikely to be mistaken for a heterozygous merle.

But dogs like this one also point to the reason why using double-merles in Collie breeding programs is a bad idea, even when someone else made the ethical compromises necessary to create the dog in the first place. Because two copies of the merle mutation damages the eyes, there is no way to know if a homozygous merle breeding animal had eye problems unrelated to the merle coloring. Dismissing eye problems with the assumption that the heterozygous offspring will not be affected could be a mistake, because there is no way to be sure that the homozygous parent has otherwise normal eyes.

With all the controversy surrounding the double-merle sire of the Westminster Best in Breed Collie, I thought it might be timely to finally get this post up about homozygous merles.

The motivation for posting this was a Great Dane I encountered at a dog fair this past fall. The dog was a homozygous merle, but the rescue worker was unaware because she believed that double-merles were “all white or nearly all white.” The dog at the top of this post is a good example of what people expect when someone says double-merle. That is often what they look like, especially in breeds that also have white patterning in addition to the merle.

This was the dog at the dog fair.

His handler did not believe he was a homozygous merle because he had more colored areas than white areas. She insisted that he was just a merle dog “marked with white.” She was unaware that some homozygous merles actually have a fair bit of coloring on them. In my experience, breeds that have solid merles (that is, merles without any white patterning) tend to produce homozygous merles with more color.

A close look at the placement of the white on this dog will show why it comes from a doubling up of the merle, rather than a white pattern. Here I’ve filled in his merled areas so that he looks like a black dog with white patterning.

Here are some white patterned dogs to compare, starting with a Shetland Sheepdog. He has the irish spotting commonly seen in herding breeds.

Here is a very similar kind of white spotting found in Boxers. (This was the pattern discussed indirectly in this post.)

And here is an Ibizan Hound with the pattern sometimes called extreme piebald.

Even though the edges on the last example are more ragged and irregular, it still looks quite different from the tinted image of the merle Dane. The placement of the color is wrong for any of these patterns. Here is what it does resemble.

These two patterns look much the same. That is because the only real difference is that the dog above has white areas where the Harlequin gene came and stripped the gray coloring away, leaving those areas white. The dog below (whose patches are actually gray) had this color stripped away by a second dose of merling. The white areas on both dogs have an outline and placement consistent with merle, not white patterning.

The white areas on this Dane do not make sense for any of the common white patterns found in dogs. Look at the difference between his two front legs, where one is white well up to the body and one is dark down to the end of his foot. His hind legs are similarly patched and uneven, just as might be expected with a merle, but not with an irish or piebald dog.

The other giveaway are his eyes. His handler believed his eyes were fine, and that they just looked odd because his one eye was particolored. Particolor eyes can make it hard to assess eyes, but the problems with his eyes can be seen despite their coloring. This first photo shows how the black pupil of the right eye has “bled” down into the lower part of the eye. This is common among homozygous merles. His left eye, meanwhile has an unusually small pupil, which is why the eye appears so very blue in this picture.

If you look carefully at that first eye picture, you might notice an odd angle to his eye. I suspect from this shot, it is something more likely to jump out at that of us who sculpt animals. These next pictures show it more clearly.

If the nature of his pattern was not enough of a clue that he was a double-merle, his eyes would give him away. Defects like this are typical.

This is also one of the reasons why the production of homozygous merles tends to generate some very emotional reactions. This particular dog has eyes that certainly look “wrong”, but his appearance – as double-merles go – is actually pretty mild. The eye deformities in many other homozygous merles are quite frankly disturbing to see. It is not just that homozygous merles are often blind and deaf, but that fact that hey look maimed is particularly upsetting. This probably contributed to rules in many countries that merle to merle breeding is abusive and therefor not permitted. Unfortunately, in the United States the Rough Collie registry has no such rule.

I am still playing catch-up with the Splash Project page, with more homozygous horses (like this Paint mare owned by Julia Lord) to add, as well as links to some interesting negative tests. I did not realize that an unexpected week away would put me quite so far behind!

Until I am caught up, there are a few important bits of news. A few horses have surfaced that have tested positive for one of the other versions of splashed white, SW2. One can be seen here. Reports are that she is SW1/SW2. It has also been rumored that the Quarter Horse stallion Colonels Smoking Gun carries the SW2 version. Whether his is the only line, or if there are others, is not yet known. So far I have not heard of a horse that has tested positive for SW3. Hopefully some of those will turn up soon.

It is interesting to note that the linked SW2/SW1 mare has somewhat less white on her body than the horses that have been testing homozygous for SW1. That will be something interesting to watch for among the horses that have a combination of two different versions. Even though their basic look might be the same, as has been reported, there may yet be visual differences that people good at pattern identification may see.

And that brings me to my own limitations. I have said that I am a phenotype researcher; I look at and analyze the visual appearance of horses. I look at a lot of horses, and I study family groups and trends within them, but I am not a molecular researcher. I have had what amounts to a crash course in the molecular end of this subject in the last ten years or so, because it has become increasingly relevant if one wants to grasp the current research. But it goes without saying that at that level, there are gaps in my knowledge. And I will likely never be as comfortable with that part as I am with determining tonal and pattern differences. So be aware, when reading this blog, that I am first and foremost an artist by trade.

I try to keep that limitation in mind. It is very important to me that this blog not perpetuate bad or misleading information. I have tried to simplify concepts presented here, because most readers are either artists or breeders or owners, but simplification itself can be misleading. I’ve been told that this is the case with the “one slot” explanation for KIT mutations. I was fortunate that someone with far more background in the technical end of genetics was able to point me to some relevant research, and hope to post a clarification in the near future. For the moment, though, let me throw down a marker that the subject of KIT mutations is more complex than that.

I also have questions about the nature of alleles, which others have expressed in other venues. The question I have had is whether or not these different versions of mutations (like SW2 and SW3) occur independently of one another, or does the original mutation get altered as some point. That is, was there one splashed white (presumably SW1 since it is most common and occurs in very old breeds) that changed into SW2 and SW3? Or did completely new mutations occur in the same general area and affecting some of the same functions? Since each dominant white mutation was like that – separate instances of similar mutations – we know that the latter scenario can happen. Is that what usually happens?  Knowing this might tell us something about where to expect – or perhaps where not to expect – the less common (and perhaps as-yet-unidentified) versions of splash. I hope to send out some queries along those lines, and report back what I find.

Like I mentioned in the previous post, I became an avid collector of any examples of splash I could find. One of the most interesting “finds” I made was this particular foal, April’s Spumoni.

She appeared in the American Tarpan Studbook. I should caveat the title with the statement that while these horses were called “Tarpans” at the time, in actual fact they were not exactly Tarpans. Authentic Tarpans have been extinct since the last one died in a Russian zoo in 1909. Here is the last known photo of a living Tarpan, taken in 1884.

The Tarpans in the book are more accurately called Heck Horses. They are so named for the German biologists, Heinz and Lutz Heck, famous for their theory that extinct animals could be recreated by back breeding. That is, they felt that the genetic material that remained in domestic descendants of the original horses could be concentrated through selective breeding, until something approaching a true Tarpan was obtained. In addition to the Tarpans, they attempted to recreate the extinct Auroch.

The work of the Heck brothers is very controversial. The projects, which were conducted at the Tierpark Hellabrunnin in Munich, are often said to have been Nazi-funded. But perhaps more importantly from a genetic standpoint, there are problems that extend beyond the initial premise, which was itself controversial from the start. Questions remain about just how accurate was their understanding of the animals they were trying to recreate. (To be fair, the existing information they had to work with was itself questionable. The Tarpan pictured above, for instance, is thought by some to be of questionable origin.) It is also said that their research was not transparent; the details of what crosses were used were not preserved. Lacking modern molecular tools, they were also limited to what they read in historical accounts, and what they could see in the (alleged) domestic descendants.

Those are a whole lot of qualifiers to say that the little filly at the top was not really a true Tarpan, and may not have actually had any Tarpan blood in her makeup. It would be a mistake to say that she is proof that splashed white originated among the Tarpans, and made its way from there to domestic animals. Not when two of the breeds believed to be utilized by the Heck brothers were the Icelandic and the Gotland, both of which have modern individuals that have tested positive for the SW1 mutation.

But her situation does have something potentially interesting to tell us about splashed white.

I was surprised to find a splash in that stud book, to say the least. Her minimally-marked parents were even more puzzling. At the time I obtained my copy of the studbook, most of the splashed white horses I had found were from American breeds (Paints, Saddlebreds) or Welsh Ponies. I had not even begun to suspect that the pattern was incompletely dominant, and I had not yet encountered Gotlands Ponies and the way the patterned appeared among them. (I had seen and handful of Icelandic individuals, but was not able to track their backgrounds.) April’s Spumoni was a puzzle, because her parents were so minimally marked. They were both marked with white, which was why they both appeared in the Appendix of the studbook. Her sire had one white coronary band and a small snip. Her dam had a tiny star and a small snip. If Gambling Man has parents that left me scratching my head because I couldn’t figure out which was the culprit, Spumoni was puzzling because I could not imagine how either could be the culprit. They had “ordinary” markings.

That was close to 20 years ago, when I still imagined that there were “ordinary” markings. Markings that did not mean anything. Needless to say, I gave that idea up some time ago. Markings, and what they mean, is the question that drives most of my personal research these days. Back when I first encountered Spumoni, I wondered whether something was tamping down the pattern on her parents, or whether something was amping up the white on her. Initially I overlooked the possibility that it could very well be both, and that the range of patterns out there were being subtly altered by all kinds of boosters and suppressors.

Which is why I think Spumoni is all the more interesting in light of some of the most recent tests. I had noted in the past that some of the seemingly homozygous splash horses (what we would now assume to be SW1/SW1) had parents with almost no white. As more horses turn up with really conservative parents, it is interesting to ask just how minimal can a heterozygous SW horse be when no white boosters are present. It is certainly true that some of the Gotland parents are quite minimal. What was true about Spumoni is that she came from horses solid enough to pass for the regular register, which required that horses be unmarked. Her parents were marked, of course, and that placed them in the Appendix. All four of her grandparents, though, were registered as unmarked. In the cases where photos are available, the individuals look truly solid. Spumoni also had a full sister that had white feet, and her sire had a full sibling with a blaze and socks. All these horses trace back to unmarked horses. It is possible, of course, that the zoos involved misidentified the horses when compiling the studbook. (The early horses were all the property of zoos.)  Still, it was a small breeding community, with a small group of founder animals, so it seems unlikely that several of the more influential founders were falsely described as unmarked.

As more horses are tested, we may find out just what those outer limits are. The idea that we may start getting clues about what causes markings on horses is very exciting. That is the big puzzle, after all.

I have gotten a number of messages lately that have made me realize that it might be helpful to clarify the term Classic Splash. I began using that term in place of the commonly used “obvious splash” when I realized that if there were differing views about what was and was not splash, the word ‘obvious’ was probably not particularly instructive. If there is one thing modern testing is teaching those of us who love white patterns, it is that very little is truly obvious! I still needed a way to indicate that I was talking about something very specific, so I opted for the word classic because what I had in mind was very much in line with the pattern as it was described in the original paper by Klemola.

That was not my first exposure to the splashed white pattern, though. Credit for that goes to the pony in the picture at the top of this post. Sometime in the early 1980s, his picture was used to illustrate the entry for the Pinto Horse Association in Western Horsemen’s annual all-breed issue. I was fascinated, because I could not figure out which pattern he had. That particular photo was taken of his other side, and was angled such that it appeared that the dark area of his coat did not start until well after his poll, while much of his neck and body were colored. To someone used to looking at ordinary tobianos and overos, he just looked wrong. Very appealing, but very much like an artist who did not know what they were doing made up his pattern. Needless to say, he went into my artist reference files.

I didn’t know what he was until a few years later, when I acquired a copy of Dr. Sponenberg’s book, Horse Color.  He had a small paragraph about Splashed White, and photos of a Welsh Pony foal with the same kind of pattern. The Klemola paper was included in the bibliography, and that provided still more information and a few more pictures. From that point on, I began to collect images and background information on anything with a similar pattern. Like most artists, I have always collected large quantities of reference images, but my interest in horse color – and patterns in particular – had become a hobby unto itself. All the white patterns interested me, but none so much as the elusive Splashed White.

My early reference files are filled with advertisements torn or xeroxed from magazines. This gave me a better idea of the range of expression to the pattern, but still the information was limited. I knew that other patterns, like sabino, could occur in such a minimal fashion that the average person did not realize the horse was a pinto until it produced something more extensively marked. If that was the case with the Splashed Whites, it was often a rather big jump from minimal parents to really loud offspring. With sabinos, I could often pinpoint where the color was likely coming from in the pedigree. With splashes, it was often not especially clear. Here is Gambling Man, one of the better-known of the Splashed White Paint Horses from the early 1990s.

Those are his parents in the inset clipping. So did his color come from his sire, with his blaze and four white feet? Or maybe his dam, with her irregular face marking that covered her nose? My files were full of horses like this, where it was impossible to narrow the source of the color down even to one side of the pedigree. Of course, this was also before the use of the internet was widespread, so there were no online databases or easy access to images, so often the background information was incomplete.

It was actually the format that I used to organize my files that led to the realization that Splashed White was probably incompletely dominant. I always entered horses into my notebooks with as much pedigree information as I could find, because I was usually looking for the color line. That is, I wanted to know where the color came from so that I could more easily rule related horses in (or out) for a given pattern. When color printing became feasible, I began color coding the names to note whether or not the horses in the pedigree were known to have a color or pattern, were suspected of it, or could be ruled out. What made Splashes so maddening was that I couldn’t even rule out one side of the pedigree on any of the entries. It took a while, but eventually I realized that wasn’t the problem; that was the answer. I couldn’t rule either side out because it came from both sides.

After that, the color began to make a lot more sense. The pattern did not occur on a continuum, like sabino appeared to do. It often did not look like much until the horse inherited it from both parents. That was why I sought out that very specific pattern as “proof” that Splashed White was there. Anything less went into my “maybe” files. I did that because over the years of searching for these horses, I found that some things that looked promising often ended up as dead ends. (Conversely, the horses that actually produced classic splash patterns often looked anything but promising!)

As I mentioned in previous posts, I have classified two sorts of “False Splash” patterns. I should caveat that by saying that it wasn’t that horses with these types of patterns could not have splash. In breeds with multiple forms of white patterning, splash carriers might well look like these horses. But they could also prove to be quite disappointing. That caused me to be rather cautious, because I could not be sure that these horses weren’t carrying something entirely different. Here are some clippings from my files of the two types:

These are horses where the bottom part of the pattern – the legs and the underside – look a lot like splash, but the white on the face is more like sabino. That is especially true for the Arabian pictured, Raffon’s Abida. Horses like this don’t usually have blue eyes, nor do they usually produce many blue eyes.

This is the other category of misleading horses:

These guys have the right kind of face and the blue eyes, but they don’t have the body white. Their tails are usually dark, too, whereas Classic Splashes tend towards white tail ends.

Horses marked like these are not always disappointing. Sometimes they do produce Classic Splashes. My personal suspicion is that this second type is what Classic Splash (suspected SW1) looks like in its heterozygous state when paired with a white-boosting mutation like sabino. In breeds like the Paint, where white-boosting genes are consistently found, this is what a lot of horses from splash-producing families look like. In breeds where those kinds of patterns are rare or non-existent, heterozygous horses do not seem to look like this.

So some of these horses probably are splashes. That said, I could never be sure that some other combination of white patterning might not also create this kind of look. That was because horses that looked like these pictured above sometimes occur, but they do not produce the classic pattern like the ones seen on the horses at the beginning of this post. It might be that they just haven’t been bred to another carrier, or that the odds haven’t worked out in their favor. But absent a test, I have reserved judgement, just in case it was something else. While it is possible to say something is associated with this or that pattern, there are enough gaps in our understanding that it is hard to know how exclusive those characteristics might be. It is quite likely that there is overlap between the different patterns. My great hope is that the new tests will begin to clear some of that up, even as they raise new questions.