Diagnostic marker found for deadly brain disease marked by dementia, movement problems

Zooming in on a single disease and studying it intensely is often the most productive route to finding treatments. But there’s no easy way to distinguish among people living with any of the primary tauopathies — a group of rare brain diseases marked by rapidly worsening problems with thinking and movement — because the symptoms are too similar. As a result, most studies on primary tauopathies have included a mix of such diseases, even though researchers know that the diseases differ in important ways and probably require different treatments.