Parkinson’s disease patients & free 23andMe

Michelle tipped me off to 23andMe's new initiative to get Parkison's disease sufferers genotyped. Basically, if you are a sufferer, you get the service for free. The goal presumably to increase the sample size so as to pick up new possible associations. But a question: can you think of a downside for Parkinson's disease sufferers? A lot of people have genetic privacy concerns, but if you manifest a disease like Parkinson's I suspect that's the least of your worries.