Therefore, Dm carrying the LRRK2 loss-of-function mutation in the WD40 domain [53] develops the essential traits of the pathology, such as motor impairment, dopaminergic neuronal cell loss and mitochondrial abnormalities [54,55,56], providing precious information regarding PD pathophysiology mechanisms and a bona fide tool to firstly test novel therapeutic approaches to the disease. The gene discussed is LRRK2; the disease is Parkinson disease.