GRM3 and schizophrenia: Second, mGluR3 is a putative candidate gene for schizophrenia and is implicated in its pathophysiology (Corti et al., 2007a; Egan et al., 2004; Harrison et al., in press; Sartorius et al., 2008; Tan et al., 2007) as part of a broader glutamatergic dysfunction (Harrison and Weinberger, 2005; Konradi and Heckers, 2003).