SLC6A3 and Parkinson disease: Two variations of the DAT gene, which functional effects are still unclear, seem to be correlated with levodopa‐induced dyskinesias in PD: the rs393795 SNP (Kaplan et al., 2014) and the 40‐base‐pair (pb) variable number tandem repeat (VNTR) polymorphism (Kaiser et al., 2003).