Pain and Genes

Pain, both acute pain in response to noxious stimuli and chronic pain associated with injury or disease, is highly variable from person to person. New evidence suggests that genetic factors contribute significantly to this variability, along with cultural, psychosocial, and other environmental factors. Genetic mutations and polymorphisms can affect the likelihood of developing a disease that is painful. In addition there are pain-susceptibility genes that affect differences in pain response given the same degree of injury or disease. Genes also affect individual sensitivity to pain-relieving drugs. Although some genetic variants have power effects individually, most pain traits are expected to be controlled by several genes acting in concert, each gene having only a modest overall effect. Using families, patient cohorts, and animal models, researchers have begun to identify disease- and pain-susceptibility genes. Success in this venture is likely to contribute greatly to the understanding of pain mechanisms and ultimately to the development of more effective therapeutic options. In the meanwhile, knowledge that one individual may feel much more pain than another due to genetic factors over which he or she has no control ought to reduce the stigma often attached unfairly to individuals whose suffering appears to be excessive.