As parvalbumin mRNA levels in schizophrenia tissue have been observed to correlate positively with pH in several studies [36], [41], [62], [63] and TNFSF13 expression correlated negatively with tissue pH in the current study, this means that as tissue pH is lowered, parvalbumin mRNA decreases but TNFSF13 mRNA increases. Here, TNFSF13 is linked to schizophrenia.