Impaired NRG1 migration of B-lymphocytes isolated from patients with schizophrenia vs. controls has also been demonstrated that was associated with polymorphisms in NRG1 and the gene for catechol-o-methyl-transferase [COMT (Sei et al., 2007)], an enzyme required for degradation of neurotransmitters including dopamine and that has also been heavily implicated in schizophrenia via association studies (Williams et al., 2007). Here, COMT is linked to schizophrenia.