My memory was jogged after hearing a little bit about this new study.
The one I know about was dealing with adopted families, and the results overwhelmingly showed what were deemed genetic diseases were, in fact, linked to habits and not genes.
Our bodies are built and primed to heal itself and survive. We create an environment for that to fail with our habits. Obesity, the big C, and many other things are habitual (or environmental at times as well) way more than truly genetic. I know the people who don't want to believe this will search until they find the exceptions or the small percentage of the time it really is genetic. But the point still stands. Your habits are way more indicative of your future disease state than your genetics. If you don't want the diseases your family has, then don't continue their habits.
No excuses!