The second candidate set consisted of 204 candidate genes that are likely relevant to understanding genetic influences on all of the endophenotypes examined in this special issue because they are part of the major neurotransmitter and neuromodulator systems systems (dopamine, noradrenaline, acetylcholine, GABA, glutamate, and serotonin), they are involved in metabolizing nicotine and alcohol, or they are part of the endogenous cannabinoid and opioid systems. We consulted the NeuroSNP database to identify relevant genes {Saccone, 2009 #558}. The third set of candidate genes comprised autosomal 92 genes found to be associated with one or more endophenotypes for schizophrenia by the Consortium on the Genetics of Schizophrenia (Greenwood et al., 2011).
