Both NCAM and one of the enzymes that transfer PSA to this adhesion molecule (ST8SiaII) are susceptibility genes for schizophrenia and changes in the expression of PSA-NCAM have been observed in the PFC cortex of schizophrenic and major depression patients (for review see Nacher et al., 2013; Wędzony et al., 2013). Here, NCAM1 is linked to schizophrenia.