What must it be like to think that everything is genetic? I would liken it to being lost, perhaps adrift on a life-raft in the middle of the ocean. In which case, your continued well-being and your very existence would depend mostly on luck.
Therefore, if you think you have "bad" genes you might reason that there's no point in trying to live a healthy lifestyle. What good would it do? And if you think you have "good" genes you might come to the same conclusion: Why bother depriving yourself of all the pleasures of your favorite "comfort foods" when you fully expect your genes to provide good health and longevity? It's an outlook that sets one free of all responsibility.
I believe that genes are context-sensitive and, for the most part, we provide the context.
My belief is backed up by the following two books:
1) "The Dependent Gene", by David S. Moore, Ph.D.
2) "The Biology of Belief", by Bruce H. Lipton. Ph.D.
If you believe everything (for the purposes of this thread we're talking about degenerative diseases of the elderly) is genetic, what source(s) do you have to back up your belief? (The source should be something that we can check; we can't check your family history.)
Have fun.