In autosomal recessive PD, genes for Parkin (E3 ubiquitin ligase), PINK1 (PTEN-induced kinase 1), and DJ-1 (Park7, an antioxidant defensive enzyme and deglycosylase) are mutated and related to the occurrence of early-onset PD, and Parkin mutations are more frequent. This evidence concerns the gene PARK7 and Parkinson disease.