New clues as to how Parkinson's spreads from cell to cell, a process which has evaded researchers for decades, have been revealed by new research. The work is the first to link the release of alpha synuclein, a naturally occurring protein that plays a central role in the development of Parkinson's, with its most common genetic risk factor -- GBA-1 -- shedding new light on its role in the progression of the devastating neurological condition and its symptoms.