SLC6A3 and Parkinson disease: This study confirms the conservation across the animal kingdom of molecular pathways involved in manganism and PD, provides the grounds for further biochemical and genetic investigations using the C. elegans model to tackle the complex issue of environment-gene interactions in age-related DAergic neurodegenerative disorders, and unravels the essential role of extracellular DA oxidation and the NADPH dual-oxidase, BLI-3, upstream of DAT-1 requirement in the neurodegeneration pathway.