Parkinson's is a toughie - you don't really know what a patient is suffering from, just the syndrome they're exhibiting. I "have Parkinson's", by which I mean I

Parkinson's is a toughie - you don't really know what a patient is suffering from, just the syndrome they're exhibiting. I "have Parkinson's", by which I mean I have a series of symptoms that aren't related to any known purely-genetic disease (there are several, and I've been tested for all of them), tumors or structural issues in the brain (lived many a night in various scanning devices), are similar in general tone to those common to Parkinson's sufferers, and which respond well to treatments for Parkinson's. The syndrome itself, though, is a bit idiosyncratic, and may in fact be a constellation of similar diseases rather than a single disease. Diagnosis is still mostly a process of observation and elimination, despite what a few optimistic studies may have reported.