这个基因编码人类至少三种阿片受体中的一种；mu阿片受体（mor）。MOR是内源性阿片肽和β-内啡肽、脑啡肽等阿片镇痛剂的主要靶点。MOR通过对多巴胺系统的调节，在依赖于尼古丁、可卡因和酒精等其他滥用药物方面也发挥着重要作用NM 001008503.2:c.118A>；G等位基因与阿片类药物和酒精成瘾以及疼痛敏感性的变化有关，但其因果关系的证据并不一致已发现该基因编码不同亚型的多个转录变体。虽然典型mor属于7跨膜g蛋白偶联受体超家族，但该基因的某些亚型只有6个跨膜结构域。[由RefSeq提供，2013年10月]
This gene encodes one of at least three opioid receptors in humans; the mu opioid receptor (MOR). The MOR is the principal target of endogenous opioid peptides and opioid analgesic agents such as beta-endorphin and enkephalins. The MOR also has an important role in dependence to other drugs of abuse, such as nicotine, cocaine, and alcohol via its modulation of the dopamine system. The NM_001008503.2:c.118A>G allele has been associated with opioid and alcohol addiction and variations in pain sensitivity but evidence for it having a causal role is conflicting. Multiple transcript variants encoding different isoforms have been found for this gene. Though the canonical MOR belongs to the superfamily of 7-transmembrane-spanning G-protein-coupled receptors some isoforms of this gene have only 6 transmembrane domains. [provided by RefSeq, Oct 2013]