DATs are enriched in SNc and VTA DA neurons, with highest expression levels reported in SNc, in both mouse and human brains (Ciliax et al., 1995; Poulin et al., 2014), and differential DAT expression has long been hypothesised to be a driving factor in sensitivity to PD on cellular and population levels (Lohr et al., 2017; Ritz et al., 2009). This evidence concerns the gene SLC6A3 and Parkinson disease.