Studies of GRM3 mRNA do not show clear differences between schizophrenia cases and controls (Ohnuma et al., 1998, Richardson-Burns et al., 2000, Egan et al., 2004, Bullock et al., 2008, Gonzalez-Maeso et al., 2008, Kim et al., 2012) although there may be a modest increase in prefrontal cortex (Sartorius et al., 2008). The gene discussed is GRM3; the disease is schizophrenia.