Hi it is ment to be bad luck!
Some are from pet stock but some occur naturally you just need two rabbits with the same gienes
When breeding pet rabbits you take these things in to account and you get out what you put in or a throw back or a different colour. Breed the colour in and hayprestow you start breeding colour rabbits.
Have seen a few about in my time blue opal black and orange.
I think I put it on another post, we were out with the hawks a we saw an albino squirrel and the birds just let it run by up a tree and then from tree to tree, they must have thought it was one of ours fer