SO FAR NO ONE KNOW

In my little experience, I would believe it's a 4-5 gene that make these. Let's say it's a multiple recessive gene combo. (some genes involved could be dominant too, don't know).

I think it would explain better why there is more "PARADOX" in the Ivory/YB than there is with Pied, Albino, Spider etc.....

I would believe the probability of this makes more sense than the Chimerism stuff IMO.