I've heard of several cases of programmers getting ALS. This seemed statistically unlikely, since the ALS site stated that only 5 in 100,000 acquired the disease.
It suggests that programmers do have higher risks. (Still, keep in mind that the study is small, and even if there are increased risks, the odds are still low.)
Then, I googled "programmers ALS" and found this study: http://aje.oxfordjournals.org/content/162/12/1146.abstract
It suggests that programmers do have higher risks. (Still, keep in mind that the study is small, and even if there are increased risks, the odds are still low.)