The iDA so generated expressed the generic dopaminergic markers TH, dopamine transporter (DAT), aromatic L-amino acid decarboxylase (AADC), and vesicular monoamine transporter 2 (VMAT2) and were also shown to release dopamine but only partially restored dopamine system functions in vivo in animal models of PD. Here, SLC6A3 is linked to Parkinson disease.