The CASK-TBR1 protein complex regulates the expression of glutamate receptor, ionotropic, N-methyl-D-aspartate 2B (Grin2b, also known as Nmdar2b; Wang et al., 2004a,b), which is critical for learning and memory and involved in autism and schizophrenia (Kristiansen et al., 2010; O’Roak et al., 2012b). Here, GRIN2B is linked to schizophrenia.