[Yorkiemom1]

I have never investigated this, because it is not something I have to worry with. Either one of this breeding pair, could be bred with another dog, and as long as the other dog is not also a carrier, neither dog will produce another blue born. If her breeding pair comes from very well known lines, and she paid probably $3500.00 or more, for each dog, then it may be worth her time and energy to get educated on genotyping and carriers for this recessive gene, and pedigrees for at least 12 generations back....but less than those circumstances, I would suggest she have both dogs fixed. To your question about this gene ever been isolated....like I said, I do not know simply because I have not had reason to get into that....I do think it is because there are more and more carriers being produced, then sold to people that are then turning around and breeding those dogs, not even aware of their dogs having this in their pedigree....producing more and more carriers, being sold and bred, and the beat goes on...........
The really wonderful thing about having breeding pairs that come from long, established, proven lines, like Wildweir, Windamere, Clarkwyn, Durrer, Pastoral, Rothby....these are a few of the greats, you have a history behind these dogs....if you do have a litter that has a pup with an issue, you can drill down into these dogs pedigrees, and you can much easier pinpoint what you can not cross again. When breeding dogs whose pedigrees have no history, you dont have a clue what is behind the dogs on the pedigrees....this is why we are getting so many faults and genetic issues....unable to track a history of an established proven pedigree, so there is no idea who is carrying what and who you can not cross with whom.