Originally Posted by Reno Bay
It's highly likely to be an environmental factor since it is only in horses living in Argentina (Arabians, Thoroughbreds, etc.) so it technically isn't a pinto pattern as it wouldn't be hereditary if it was environmental. I would call it an environmentally-induced pinto mimic XD
Gotta say, though, it's a gorgeous thing to look at.
I don't know. I think I am in the "recessive gene" camp. If it's environmental, why do we not see more of it? For that matter, if it's environmental, is it something mares are exposed to during gestation? I can't find any pictures of a foal displaying the pattern, but if it were something that was a drastic change of coat like a fungal infection could cause, why are there no reports of that part of it?