SNCA and Parkinson disease: Given the increasing evidence that the transmission of pathological alpha-synuclein between neurons plays a central role in Parkinson’s disease progression [5,6] and that pathology may start in the ENS and spreads to the brain via the vagus nerve [8,9], strategies targeting these organs could be a potential therapeutic approach to prevent progression at the prodromal stage in body-first Parkinson’s disease patients.