I just emailed a friend that works in a research lab to see if she can get me a copy of the full article from the Annals of Neurology. I don't mind getting tested, but frankly I want to find out what kind they are so I can figure out what their favorite foods are :).
If I've had them for 6 years, they can't be all bad. The article (I've read a few dumbed-down versions in the last hour now) says they're common in some parts of the world, so they can't be too harmful or cause too many symptoms. Maybe their favorite food is chocolate?
If they can't get it, ask someone with access to a medical library, e.g. a doc with hospital privileges.