GRM5 and Parkinson disease: Compared to control cases, in DLB there was a significant increase in the levels of mGluR5 immunoreactivity in neurons in the frontal cortex (Figure 1A, B, D), hippocampus (Figure S1, A, B, D) and caudo-putamen region (Figure S1E, F, analyzed in H) Compared to controls, in the PD cases, levels of mGluR5 were increased in the caudo-putamen (Figure S1E, G, H).