I was doing some reading, and tho a lot of hybrid-oriented articles refer to the males as being sterile, some mention that females are, or are very possibly fertile . If this is the case, then, my idea from many years ago, to produce as close to an Albino form of Borealis as possible, would be to Cross a Male X borealis w/ a female albino or retic...from the mature offspring, take a Female with albino traits, and breed her with a pure Male borealis, and those offspring would have heavier borealis traits, and include some albinos or reticulated form...a couple people over the years said they think that could be a possibility, not a definitive. But the only way to find out, is to attempt.
Btw, I want to let everyone know, the "cross-breeding" is not a full-time effort on my part...I want to achieve it a couple of times, partially for research, and partially out of curiosity, as to what those frogs would look like, and I would ONLY give them to friends,etc.
NO, I would not be taking the hybrids to petshops for that exact reason Geoff mentioned in the previous reply. All other breeding would be normal same-species breeding. As well, because Muelleri & borealis have such striking spotting & pigmentation, I am very curious to see what those hybrid offspring would look like, etc...I hope I haven't upset anyone by talking about it here..I apologize if I did.
Sincerely - tommy