Morphine Dependence is related to withdrawal disorder and heroin dependence. An important gene associated with Morphine Dependence is OPRD1 (Opioid Receptor Delta 1), and among its related pathways/superpathways are GPCR downstream signalling and Class A/1 (Rhodopsin-like receptors). The drugs Naloxone and Clonidine have been mentioned in the context of this disorder. Affiliated tissues include brain and spinal cord, and related phenotypes are nervous system and homeostasis/metabolism