Miller NS, et al. - The experts embraced this study to ascertain whether dopaminergic (rs1076560 DRD2 G > T and rs4680 catechole-o-methyltranspherase (COMT) Val158Met) or brain-derived neurotrophic factor (rs6265 BDNF Val66Met) genetic polymorphisms were correlated with gait function and medication responsiveness in Parkinson's disease. They proposed that genetic subgrouping could be used to identify Parkinson's disease patient subgroups that were more dopamine responsive for gait function, particularly for DRD2.