Immunohistochemical double labeling with antibodies against alpha-syn and mGluR5 showed a small degree of alpha-syn co-localization with mGluR5 within the frontal cortex of controls (Figure 5A-C) however the degree of co-localization was greatly increased in the DLB (Figure 5D–F) and PD (Figure 5G–I) cases. Here, GRM5 is linked to Parkinson disease.