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I was reading a genectic thread on here(we so need a genetic place), and I got to thinking-
Why do most horses have a blazes, stripe,snip, and most commenly a star on their forheads, even if they don't have any pinto breeding and they and their ancestors a bay, brown, or black? Where does it come from? Because Ive seen very few horses that don't have one of those on their head. I mean, ive seen them, heck, our neighbor has one like that. Also, what with the striped hooves if they don't have appy or paint in them? Because ive also seen that. I know it has to do with genetics somehow, but i'm not sure. I prefer to think of it just being "random",lol, even though I know its affected by genes. So, please explain! :)
 

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My thought (I may be wrong) - is the genes mutate and react as a color deformity; AKA the stars, strips, blazes, socks, stockings, etc..
 

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Widely striped hooves are pretty common on a horse with a white leg marking-- any white leg marking, not just the high/etra white associated with pintos. Generally, white leg markings down to the coronet band make the hoof "pink" (really, more shell colored), dark legs down to the coronet band make the hoof grow grey or black. iI the otherwise white leg has even small specks of pigment at the coronet band, the hoof can grow striped both pink and black.

The more narrowly striped hooves on an Appaloosa are a totally different mechanism. They occur on the DARK legs. Usually the foal is born with dark hooves, and they grow in striped (sometimes they are born with striped hooves-- its not as common though.) A horse who is believed to be homozygous for the LP gene that enables appaloosa coloring often has almost totally pink hooves on its dark legs, maybe with just a few narrow dark stripes. An Appaloosa with regular white leg markings will have hooves like any other horse with white leg markings-- the white leg markings eclipse the dark legs needed for the appaloosa striping to show up.
 

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ive thought of this and you can see it in all animals although it is more dirverse in horses...
 

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These types of markings are all actually pinto genes in the very minimalised expression.

Here is a good link to read for more info: White Patterns | www.equine-color.info
There's no proof of that. Some believe it may be true, but nothing conclusive has been proven and no gene has been identified in being the cause of white markings on horses.

The truth is, at this point, nobody knows what causes these markings just as nobody knows what causes a flaxen mane on a chestnut horse. They're just breaking the bank on equine color genetics and many factors remain unstudied and unproven regardless of how many people may swear it's the gospel truth.


 

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I don't swear on it being true, but that's what most of the Equine Color site's I've read say. And ho do you explain crops outs then? If a horse randomly shows up with belly spots or pinto coloring out of two solids then obviously one of the parents is carrying a minimal pinto gene. I bet if you got a solid horse with say a high white stocking and a blaze that extends below the chin it comes back positive for Sabino.
 

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I'm not disputing that. I'm disputing the idea that EVERY horse with white carries the pinto gene. We all know that pinto genes can hide for generations, and that explains a lot of cropouts - but that's the ACTUAL frame or splash or sabino hiding and then popping out.

I'm disputing the idea that a Lusitano horse for example, which has never had an occurance of any pinto, has white markings because of a "pinto gene".

It also fails to explain why very blatantly "tobiano" style markings would be attributed to a form of sabino. Solid horses with leg markings and facial markings almost always have exclusively tobiano styled markings if a common pinto gene is not found in them. Horses with high splashy whites or splashy faces are almost always found to have a pinto gene expressing minimally.

So my only point is that nobody ACTUALLY knows what causes white markings on a solid horse with NO identified pinto gene (frame, splash, sabino, tobiano).
 

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Horses like ou explained are generally thought to have minimal tobiano. And while I understand what you are saying, I am leaning towards believing it. There is no explination for it besides this one, and in my head it makes pefect sense.
 

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OK I have now lost the track this thread has taken.

I am not convinced that EVERY occurence of white leg/face markings is because of a "pinto causing" gene like splash or one of the various sabinos. I think a case can be made for the existence of "normal" white leg and face markings-- for example one or 2 white anklets and a star, maybe a star with a conservative strip--- as "normal" markings that can exist in the absence of sabino/splash/etc.

That said, I DO believe that occasionally sabino and splash can be present in horses that have what appear to be "normal" leg and face white-- the sabino/splash/etc. doesn't get expressed more typically due to suppressors. But IMO that doesn't mean that EVERY horse that has "normal" looking conservative leg/face markings is harboring suppressed splash/sabino/etc.

But HOW is this related to tobiano? Other than a tobiano without splash or one of the various sabinos might exhibit the "normal" face marking of a star or star and strip-- etc? I do NOT believe that minimal/suppressed tobiano is the cause of "normal" white leg and face markings.... if that is what is being postulated? (and as I said, I feel like I am not on the same track as this thread so I could be misinterpreting,..... LOL)
 

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Eastowest

Haha, it's ok, you're thinking like I do! The latest "theory" circulating is that every white marking is caused by a so-called yet undetected sabino gene (I have not personally heard anything about it being an unidentified tobiano gene as we've already identified that and horses with tobiano markings show as being tobiano always). They believe that because certain horses show sabino like markings and yet test negative for sabino 1, that there are unidentified additional sabino genes that cause this phenomona and somehow that also translates into EVERY horse with even a speck of white carrying one of these illusive sabino genes.

I am in the same ballpark as you because I don't understand in the least how the VERY tobiano type markings seen on "normal solid horses" are the result of a sabino gene - such as normal stars, stripes, blazes, socks, half-socks, etc.

I agree completely that many horses who APPEAR solid are in fact carrying a pinto gene - we all know the uncanny abilitiy of sabino in particular to pretend it's "normal" and yet jump out on foals suddenly.

I also definately agree that we likely have more sabino genes unidentified if they are testing blatantly sabino looking horses and not finding sabino 1 in the genes (or any of the other pinto genes).

I don't agree, however, that every horse that's ever had a half-moon on it's forehead and a white spot on it's pastern is carrying a mysterious pinto gene and has the abilitiy to produce a pinto foal. If it IS a pinto type gene, then it would be a gene that restricted the white to ONLY the face and legs. Otherwise, it really makes no sense how we can see generation after generation of solid horses with white markings producing nothing but solid horses with white markings. Where are the crop outs if this unknown sabino gene has the abilitiy to produce full pinto? Why do they have tobiano markings if they are sabino genes?

Good example is my old mare Zena.



I'd have a hard time believeing that she's actually a sabino. Not based on markings alone, but based on her coming from a line that goes back well over 100 years of solid Arabians with white markings, none of them the least bit sabino in appearance.

I'm not saying it's IMPOSSIBLE, it just seems to be the general consensus and I am a nit picky jerkwad who can't stand theories being toted as facts. Sorry!
 

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Also, it's impossible for horses with white markings to have minimal tobiano. If it IS tobiano, you're going to see cropouts, not hundreds of years of minimal tobiano horses (exactly how two tobiano parents can produce a minimal tobiano foal). Tobiano is tobiano, there are other factors in play determining how it displays physically. The only way for that to be possible is if, like sabino, there was an unknown tobiano-type gene we haven't identified.

Which at this point, actually seems MORE likely then all these horses having a sabino gene and yet tobiano type markings. However I fimly believe that if they DO identify a pinto type gene, it will be one that restricts white to face and legs anyway with no ability to produce a full pinto.
 

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I'm sorry Eastowest, yes I am. Only in that "normal" markings are actually tobiano in appearance as opposed to sabino, frame or splash which are known for being splashy and blotchy, not defined, crisp and in angular forms as opposed to "cartoonish" forms.
 

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Hehe, I never really thought about this subject before. I just thought it happened to happen, sort of like "Frosting." Hehe

Interesting theories, you guys :)
 
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