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.
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)
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 definitely 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!
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.
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.