GRM5 and major depressive disorder: Additionally, Wang et al. (2018) recently provided the first direct evidence for mGluR5 hypoactivity in dorsolateral prefrontal cortex tissue taken post‐mortem from schizophrenia patients, although several previous investigations could not find altered mGluR5 levels postmortem in schizophrenia (Matosin, Frank, Deng, Huang, & Newell, 2013) or psychotic depression (Matosin et al., 2014).