RGS2 and movement disorder: Although pharmacogenetic studies identified the possibility of genetic risk factors (e.g., PPP1R1B, BDNF, DRD3, DRD2, HTR2A, HTR2C, COMT, MnSOD, CYP1A2, and RGS2) thus ascertaining the individual differences in response to antipsychotics, Bakker et al. [30] did not reveal a single nucleotide polymorphism associated with susceptibility to drug-induced movement disorders.