The downregulated genes included, as might be expected, those related to Parkinson's disease (PD) (Vps13d), dopaminergic neuron differentiation (Nr2f1), regulation of DA receptor expression (Klf16), DA transporter (DAT) trafficking (Vav2), but also those linked to β‐catenin signaling (Tnks), synaptic proteins (Plekha5), and stimulus–response habits (Abl2). This evidence concerns the gene SLC6A3 and Parkinson disease.