Several post mortem studies have reported that expression of the mRNA or protein of Cx43 were downregulated in the locus coeruleus, frontal cortex and thalamus of patients with mood disorders [33,67,68,69,70,71]; however, an abnormality in glial size, which suggests the existence of hemichannel or gap–junction dysfunctions, was not observed in patients with schizophrenia [72,73]. Here, GJA1 is linked to schizophrenia.