Hitherto, 26 loci associated with the risk of PD have been determined—inter alia, many PARK genes, for example, PARK1 and 4, encoding α-synuclein; PARK2, encoding parkin; PINK1, encoding PTEN-induced kinase 1 (PARK6); DJ-1 (PARK7); LRRK2 (PARK8); and ATP13A2 (PARK9). The gene discussed is PRKN; the disease is Parkinson disease.