Although carriers of heterozygous mutations have been reported to suffer from parkinsonism because of reduced expression and enzymatic activity of parkin (Klein, Lohmann‐Hedrich, Rogaeva, Schlossmacher, & Lang, 2007), PARK2 appears to exert a dose‐dependent effect on the risk of parkinsonism. The gene discussed is PRKN; the disease is Parkinsonism.