The Genetic Influence on the Cortical Processing of Experimental Pain and the Moderating Effect of Pain Status

Abstract

BackgroundResearch suggests that the COMT Val158Met, BDNF Val66Met and OPRM1 A118G polymorphisms moderate the experience of pain. In order to obtain experimental confirmation and extension of findings, cortical processing of experimentally-induced pain was used.MethodA sample of 78 individuals with chronic low back pain complaints and 37 healthy controls underwent EEG registration. Event-Related Potentials were measured in response to electrical nociceptive stimuli and moderation by COMT Val158Met, BDNF Val66Met and OPRM1 A118G polymorphisms was assessed.ResultsGenetic variation did not have a direct effect on cortical processing of experimental pain. However, genetic effects (COMT Val158Met and BDNF Val66Met) on experimental pain were moderated by the presence of chronic pain. In the presence of chronic pain, the COMT Met allele and the BDNF Met allele augmented cortical pain processing, whilst reducing pain processing in pain-free controls. No significant effects were found concerning the OPRM1 A118G polymorphism.ConclusionsThe current study suggests that chronic experience of pain enhances genetic sensitivity to experimentally induced mildly painful stimuli, possibly through a process of epigenetic modification.

Update on the genetics of the fibromyalgia syndrome

“…Thus, the adrenergic-related ADRB2 and COMT have been associated with autonomic dysregulation [34], sleep dysfunction [35], and anxiety [36], as well as with pain processing [37]. Similarly, serotoninergic-related genes such as SLC6A4 and HTR2A have been associated with depression and anxiety in FMS patients [38].…”

The Use of Event-Related Potentials in Chronic Back Pain Patients

“…For a detailed description of the protocol, we refer to Vossen et al, 2010aVossen et al, & 2011 Here, a summary of the design is given. Seventy-six pain-free subjects and 75 patients with chronic low back pain participated in the study.…”

“…In a more recent study, we investigated the influence of the COMT Val158Met, BDNF Val66Met, and BDNF Val66Met polymorphisms on pain using ERPs (Vossen et al, 2010a). The sample of this study consisted of chronic low back pain patients, as well as healthy controls.…”

Recent Advances in the Understanding of Genetic Susceptibility to Chronic Pain and Somatic Symptoms

“…Vossen et al [27] recently reported that despite there being no relationship between rs4680 and cortical processing in response to experimental pain stimuli, there was a significant interaction with pain status. Individuals with chronic LBP carrying the M allele had a significantly different response to experimental pain than those with the M allele who were pain free, but again the number of individuals included in the study was small (n =78 LBP and n = 37 healthy individuals) [27].…”