Thanks, Sara
I wasn't sure if it was off-topic or not, but coat-colour genetics in different species is one of my specialist subjects.

Human nature has the basic idea that if you breed like-to-like, you're more often than not going to get more of the same.

But even some educated ones haven't the in-depth knowledge of genetics to know what Merle (or Roan/Dalmatian in rodents) can do.

Your link to the double merle site was equally interesting to me, especially all the pics. Very clearly and easily explained: I'll be happy to have that link, to give to people who are interested in hamster or guinea pig roan genetics.

There seem to be quite a few 'lethal' genes with regards to coat colour. I knew about the roan gene as well as I used to breed guinea pigs.
Becky

So that would be an issue in roan/husky rats too?

No... roan in rats in genetically unrelated, not really a proper 'roaning' gene at all, really.

That is one of my favorite sites as far as information given, and explanations made understandable! The deaf dog list sent me that one when I was first asking questions about double merles.