You have a definite genetic predisposition to hip dysplasia, which is why they have the OFA and PennHip registries to certify dogs before you can breed them.
But overfeeding and lack of exercise in puppies and young dogs is the triggering factor. I know numerous dogs who Xray bad who have never been symptomatic -- they are all working dogs, very lean and muscular and in hard condition.
Again,
I have already ceded that environmental factors may exacerbate the disorder, but there is little doubt at this point that the underlying cause is genetic. I believe we won’t find one single “autism gene” per se, but will likely find that it is a combination of genetic markers in combination that lead to the disorder, as well as the extremely wide range of functional issues that come with it.