Early researchers found that the common genetic variation of GRM5 in schizophrenic patients would affect cognitive function, hippocampal volume and hippocampal mGluR5 protein level compared with the healthy control group, among them, the metabotropic glutamate receptor subtype 5 (mGluR5) is encoded by GRM5 gene, which is an attractive new drug target for the treatment of schizophrenia (Matosin et al., 2018). The gene discussed is GRM5; the disease is schizophrenia.