Evidence that some SNPs of the DAO, DAOA, PPP3CC, and DTNBP1 alleles contribute to conferring an increased risk of schizophrenia are counterbalanced by others indicating that they do not increase risk or even exert a protective effect (http://www.schizophreniaforum.org/res/sczgene). This evidence concerns the gene PPP3CC and schizophrenia.