PPP1R15B and schizophrenia: Moreover, the genes modified by prenatal MIA included many of those already associated with schizophrenia and autism, including Abat, Gnas, Cerk, Cnnm2, Pex5l, Ppp1r15b, Slc19a2, Pi15 and Pex2. The pathways influenced by these genes, such as the ceramide signalling pathway and AMPK signalling pathway are those involved in cell signalling and synaptic transmission fundamental to neurodevelopment and brain function62,63.