An example is provided by a SNP of the Neuregulin-1 (NRG-1) gene (X); an imbalance in Neuregulin-1 (NRG-1β) may disrupt the dopaminergic and glutamatergic functions, neurotransmitter pathways associated with schizophrenia (Kwon et al., 2008). The gene discussed is NRG1; the disease is schizophrenia.