SLC6A3 and Parkinson disease: The pathophysiology of Parkinson’s disease (PD) is characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc), leading to a denervation of the nigrostriatal tract that emits its terminal projections to the putamen and caudate nucleus with significant reduction of dopamine and, consequently, loss of DAT integrity [3,4,5].