As positive symptoms were associated with increased hyperdopaminergic activity in schizophrenia (103, 104), 27OHC as a selective estrogen receptor modulator can attenuate dopamine level by reducing the expression of tyrosine hydroxylase (TH, the rate-limiting enzyme in dopamine synthesis) via the inhibition of estrogen signaling (105–107). This evidence concerns the gene TH and schizophrenia.