rhasputin was right on this one...
I don't care if the baby rat ends up being just fine in the end... because it ultimately isn't just fine. It probably still has some genetic problems that it could possibly pass on if you make a simple mistake sometime during its life, and it ends up breeding.
It is the responsability of any reputable rodent breeder to cull anything made that should not be. Rodents aren't snakes. They breed so very easy that the right answer is only to cull what should not be.