We also identify genes that are likely to be readily targeted and modulated by drugs, and thus provide potential pharmacotherapeutic targets for addictions. G protein coupled receptors that include the δ opioid receptor and metabotropic glutamate receptor 5 display rich pharmacologies and substantial ties to addiction through abundant evidence from pharmacologic, knockout mouse and other approaches. Glutamatergic systems are also implicated by identification of “druggable” metabotropic 7, GRIK2 kainate and GRIA4 AMPA glutamate receptors, as well as several cell adhesion molecules that are associated with classical synapses. Known small molecules and/or drugs act at many of the other receptors, enzymes and transporters listed in Table 2.
