Loss-of-function, autosomal recessive mutations of the auxilin gene (PARK19) cause juvenile early-onset PD.4,15–20 A recent study shows that PARK19 mutations also occur in late-onset PD patients.21In vivo presynaptic dopamine transporter (DAT) imaging of a PARK19 patient revealed DA terminal loss, which supports a parkinsonian diagnosis and suggests that clathrin-uncoating deficits impact DA presynaptic sites. The gene discussed is SLC6A3; the disease is Onset.