We identified a differential pattern of miRNA expression between PD patients, including iPD and LRRK2-PD patients, and age- and gender-matched healthy controls, with a downregulation of miR-146a, miR-335-3p, and miR-335-5p in PD patients versus controls and no significant variation in the other miRNAs under investigation. The gene discussed is LRRK2; the disease is Parkinson disease.