An interesting article about MS. They've found a potential biomarker. It's an autoimmune antibody that "bonds with the potassium channel KIR4.1." It was found in almost half of MS patients in one study, and it wasn't found in healthy people.
Multiple Sclerosis: New Marker Could Improve Diagnosis
July 12, 2012http://www.sciencedaily.com/releases/2012/07/120712101549.htm