It's really a case-by-case basis thing. I grew up with a mutt that I loved dearly. My parents got her because my Dad had read something or other in (I think) P

It's really a case-by-case basis thing. I grew up with a mutt that I loved dearly. My parents got her because my Dad had read something or other in (I think) Popular Science about how the "dog of the future" would be a mutt, and the mutting of genes would suppress bad recessive traits. Then she got sick as a puppy, had an allergic reaction to her medication, and suffered permanent brain damage. That having been said, she was a perfect house pet; lived to be a very ripe old age and was good natured, just a little slow to respond to things. If you're a breeder and there's something wrong in the genetics of the dog you're breeding, stop breeding that dog. But resolving genetic issues isn't as simple as just throwing mutts together; you really just roll the dice on a new set of strengths and weaknesses when you do that.