SNCA and Parkinson disease: Using ddPCR, we investigated the concentrations of miR-7-1-5p, miR-499-3p, miR-223-3p and miR-223-5p—miRNAs involved in the α-synuclein pathway and in inflammation—in the serum and serum-isolated exosomes of 45 PD patients and 49 age- and sex-matched healthy controls (HC).