In view of these functions of USP19 in proteostasis and the recent recognition that it is located in a locus on chromosome 3 that is associated with Parkinson’s disease39, (https://pdgenetics.shinyapps.io/GWASBrowser/), we tested whether USP19 regulates α-syn processing and/or propagation in PD pathology. This evidence concerns the gene USP19 and Parkinson disease.