2017 Mitchell Max Awardee:
Cameron L. Randall
Doctoral candidate, West Virginia University
Cameron L. Randall is a doctoral candidate at West Virginia University, currently completing his final year of training in clinical psychology as a resident in behavioral medicine and neuropsychology at the University of Washington, School of Medicine. His research interests include: (1) psychological processes involved in pain perception, treatment-seeking behavior, health behavior, and health outcomes; (2) the etiology and treatment of healthcare-related fear/anxiety; and, (3) the dissemination of knowledge on these topics to healthcare professionals. Cameron’s program of research has applied these interests to dentistry, and recent NIDCR-funded work includes the study of genes associated with dental pain perception and their role in the etiology of dental care-related fear and avoidance of dental treatment, as well as the development of methodologies for experimental assessment of dental pain perception. Clinically, Cameron is interested in pain- and healthcare-related fear, acute pain management, chronic orofacial pain, and health behavior change.
ABSTRACT:
Variation in MC1R Gene Predicts Dental Pain Sensitivity
Cameron L. Randall1,2,3, Mary L. Marazita1,4, and Daniel W. McNeil1,2
1Center for Oral Health Research in Appalachia, 2West Virginia University, 3University of Washington, 4University of Pittsburgh
Objective
Further the understanding of genetic contributions to orofacial pain perception.
Specific Aim
Determine whether melanocortin-1 receptor gene (MC1R) variation predicts dental pain sensitivity.
Background
MC1R codes for a protein involved in normal pigmentation, which also is present in tissue of brain pathways that process pain and fear. MC1R has been implicated as potentially important in the experience of orofacial pain because variation in the gene is associated with fear of pain and dental fear. To determine whether MC1R variation influences orofacial pain perception, objective dental pain tolerance and subjective pain experience were measured in human participants using a test involving electrical stimulation of teeth. Participants also completed a self-report measure of fear of pain—a phenomenon associated with pain tolerance—and were genotyped for the most common single nucleotide polymorphism in MC1R (rs1805007).
Results
Of 96 participants (57% female, M age = 34.8 years, SD = 11.6), 18 had the minor allele at rs1805007. Fear of pain was associated with subjective rating of pain intensity (r = .20, p = .04). Controlling for fear of pain, presence of the minor allele was predictive of lower objective pain tolerance (ß = .22, p = .03; R2 = .09, F(2,93) = 5.62, p = .005), indicating that MC1R variation is associated with greater sensitivity to dental pain.
Significance
This study advances the literature on genetic influences on orofacial pain perception. Specifically, it is the first known study to link MC1R variation to increased dental pain sensitivity, with findings strengthened by use of an experimental pain induction paradigm for objective pain sensitivity measurement. Future work may elucidate mechanisms underpinning associations between MC1R and orofacial pain perception and/or clarify the role of orofacial pain perception in the association between MC1R variation and dental fear, which is an important barrier to oral healthcare.