It may be that “breedability” was bred into dogs by humans. If there is indeed a trait in the dog genome that makes mutations more likely, that trait itself might have been selected for in the process of breeding dogs for more observable traits.
As for cats, they’re not really as domesticated as dogs to begin with. For the most part, the job humans want cats to do is to hunt down mice and other vermin, which is basically what a wild cat would be doing even without domestication.
Err…did you read my post (#22)? New(ish) research indicates there are specific genetic reasons for the variability in dogs. It’s no longer the mystery we once thought.
Err…did you read my post (#22)? Not only are these traits named and described, but it appears they predate domestication, so it’s not something “bred into dogs by humans.”
I did miss your link.
It’s an interesting study. I don’t think it’s as case closed as you appear to believe though; this is not the first hypothesis on dog breedability with any support. As I implied in my post, the reason that new breeds of dog can be created relatively easy is probably due to a combination of factors.