Contribution of the COMT Val158Met variant to symptomatic knee osteoarthritis

摘要

There is extensive literature reporting discordance between the presence and severity of symptoms and the degree of radio-graphic structural osteoarthritis (OA). Genetic differences may account for some of this discordance. Indeed, certain genetic variants implicated in pain sensitivity have been shown to be significantly different between asymptomatic radiographic cases of OA and symptomatic cases. The catechol-O-methyltransferase, encoded by the COMT gene, is a major degrading enzyme in the metabolic pathways of catecholaminergic neurotransmitters. Genetic variation at the COMT gene has been shown to result in differential pain sensitivity. Carriers of the Vall58Met COMT variant have been reported to have a higher risk (OR=2.9, 95% CI 1.2 to 6.1) of hip pain as compared with carriers of the Val/Val genotype among those with hip OA. This result has not been replicated in independent cohorts, nor for OA in other joints.