Finally, Arion and Lewis (2011) analyzed mRNA expression levels of NKCC1 and KCC2 and their associated regulatory kinases STK39, OXSR1, WNK1, WNK3, and WNK4 in the dorsolateral prefrontal cortex of subjects with schizophrenia compared to non-psychiatric subjects and reported no differences in the expression of either KCC2 or NKCC1 transcripts. This evidence concerns the gene SLC12A5 and schizophrenia.