Genetic and Epigenetic Mechanisms Linking Pain and Psychiatric Disorders

The neurophysiological link between neuropathic pain and depression remains unknown despite evident high comorbidity of these two disorders. However, there is convincing evidence that genotype plays a role in both pain and depression. Using various types of genetic analysis - population genetics, cytogenetics and molecular technologies - specific genes have been implicated in mediating almost all aspects of nociception and mood disorders. The current review attempts to identify specific genes and epigenetic mechanisms common to both disorders. It is concluded that external and internal factors (inflammation, stress, gender, etc.) that contribute to the pathologies may do so through epigenetic mechanisms that may affect expression of these particular genes. The possible involvement of epigenetic regulation in pain and psychiatric disorders suggests that treatments targeting epigenetic mechanisms that mediate adverse life events should be considered.