OPRM1
OPRM1 (Opioid Receptor Mu 1) encodes the mu-opioid receptor, a G protein-coupled receptor primarily responsible for mediating the analgesic effects of opioid drugs and endogenous opioid peptides. It plays a critical role in pain modulation, reward pathways, and the development of opioid dependence and tolerance. Genetic variations in OPRM1 can influence individual responses to opioids, impacting efficacy and side effects in pain management and addiction susceptibility.