Oooo your going into colour genetics now a very complicated subject
Anyway I don't know too much as I rely on other people to keep me right

but Blue is a dominant colour. It also depends on what dog and bitch you mate and what gene's they carry. For example Buttons is a Liver Roan out of a Liver to Liver mating. If I mated her to a blue dog that only carried the blue gene I would only get Blue puppies no Livers as Liver is a recessive colour. It get's very complicated
Whilst we're on the subject? if I mated Butty to a dog that carried Blue & orange would I get Blue & orange puppies, meaning do both parents have to carry the Orange gene as it's a recessive colour to produce puppies?? And how would I know if she carries the orange gene?? Or am I talking out my bottom