COMT and schizophrenia: Pleckstrin has been associated with schizophrenia (linked to a catechol-o-methyltransferase Val108/158 Met functional polymorphism), and Sei et al. [69] have recently reported that neuregulin1-ErB signaling is PI3K/Akt/Pleckstrin dependent and impaired in patients with schizophrenia.