CLDN3 and schizophrenia: A similar approach from the same research group examined 10 schizophrenia brains and 15 healthy controls and found gene expression for schizophrenia was similar to the ASD study and protein expression appeared to follow a trend similar to ASD, namely, a trend toward reduced CLDN-5, CLDN-3, and reduced cortical CLDN-12 protein levels associated with blood–brain barrier integrity and function.