Replies on Duration of Immunity and Rabies Vaccination

If it's genetic then how did it "spread" to other purebred dog breeds and to cats?
Or are genetic diseases now contagions? Sounds auto-immune related to me.
I think the problem is that most studies are not accurate. The scientists go in thinking "genetic" and then they find a gene that may or may not actually be the cause, but because they were ONLY looking for a gene, they eventually find one.
I read an article about this, it's one of the major flaws with how studies are developed and run. I'll see if I can find it.

Thanks Jen, I had similar questions about this being a genetic defect in my post above, and the connection between DM and rabies. If you are familiar with this, do you mind reading my post (one of the first posts above) and maybe have some more information for me? I really appreciate Dr Falconer's blog posts but this one left me feeling like there was something missing (maybe even wrong?) about the intended message, and the science. This disease is very close to my heart, and I want to be as informed as I can be. I am not a scientist, I try to learn from googling.