Genetic Variations of OPRM1, OPRK1, and COMT Genes and Their Possible Associations with Oral Pain in a Population from Argentina.

AIMS

To analyze in a population from Argentina the variation of three genes involved in the control of pain pathways-two genes that code for opioid receptors (OPRM1 and OPRK1) and COMT, which codes for an important enzyme in the control of neurotransmission-and to evaluate the associations of these genes with oral pain and the need for analgesics in the population under study.

METHODS

A total of 134 volunteer donors from the city of Resistencia and 27 donors from the Wichí community for comparison were analyzed for 13 single nucelotide polymorphisms (SNPs) and 1 insertion/deletion (Indel) localized in the three genes using polymerase chain reaction-restriction fragment length polymorphism or standard PCR and electrophoresis. All 134 individuals from Resistencia provided biologic samples for DNA analysis, and a subset (n = 81) agreed to answer a questionnaire for an association analysis. Statistical tests for a possible association between genetic variation and self-reported ethnic origin, oral pain, and need for analgesic drugs were performed.

RESULTS

Significant differences were found when the study population was compared to populations from other continents, as well as between the two studied populations (P < .05). A positive association was suggested for the COMT gene from Resistencia with both oral pain intensity and analgesic requirements.

CONCLUSION

The admixture process that occurred in the past of Resistencia probably contributed to a genetic differentiation in this population, and this genetic variation might influence phenotypic expressions of pain perception and analgesic requirements.