Here are names that many of you will recognize commenting on this. it's the same link as in my first post in this thread but these are medical thought leaders - Olanow, Lang, Langston and more.

excerpt:

ARTICLE IN BRIEF

A theory gaining traction among some Parkinson disease (PD) experts is that PD may be a prion-like disorder, based on evidence that alpha-synuclein can be transmitted from neuron to neuron, leading to the development of Lewy body-like inclusions in the receiving cell, and other findings from neuroanatomy, fetal transplantation surgery, and basic science.
Is Parkinson disease (PD) a prion-like disorder, with alpha-synuclein playing the role of infectious protein? The answer to that provocative question may be “yes,” according to a growing number of PD experts, as they consider findings from neuroanatomy, fetal transplantation surgery, and basic science


http://journals.lww.com/neurotodayon...xperts.12.aspx