What Is Genetic Contribution To Clinical Pain?

Genetic factors:
Pain is a complex human trait sculpted by multiple biologic and psychologic systems, each of which involves the influence of numerous proteins throughout the peripheral and central nervous systems, whose effects can be substantially affected by environmental exposures. Therefore, it is inevitable that multiple genes, each with a small individual effect, interact among themselves and with a variety of environmental factors, to influence pain sensitivity and the expression of chronic pain conditions. Twin studies have demonstrated that genetic influences account for approximately 50% of the variance in chronic pain.
Moreover, candidate gene association studies have identified multiple genes that may contribute to clinical pain. Several studies have shown that polymorphisms in genes affecting the function of both catecholaminergic and serotonergic systems may be associated with chronic pain disorders, such as FM and TMD. However, which genes contribute explain the greatest proportion of variance in clinical pain responses is currently unknown, and the direct functional effects of specific polymorphisms have generally not been elucidated. Better understanding of pain-related genetic influences will provide important insights into pain mechanisms and may identify new targets for pharmacologic and other therapies.
In more direct tests of the genetic contribution to clinical pain, twin