The following is a summary of “Polymorphism Val158Met in the COMT gene: disrupted dopamine system in fibromyalgia patients?,” published in the June 2024 issue of Pain by Gerra et al.

The single-nucleotide polymorphism (SNP) rs4680 in the catechol-O-methyltransferase gene (COMT), encoding Val158Met, is associated with modified COMT enzyme activity and implicated in chronic pain conditions like fibromyalgia (FM), with varying research outcomes.

Researchers conducted a retrospective study analyzing the role of SNP Val158Met in FM and assessing the interaction with FM comorbidities (depression, sleep impairment) and pain intensity.

They examined the genotypic frequencies of SNP Val158Met in 294 patients with FM, 209 HCs without comorbidities, and pain-free controls. Using logistic regression, they assessed the associations between genotypes, FM risk, and symptom severity.

The result showed that the G allele (Val) was more prevalent in patients with FM (57.8%) than in HCs (48.8%; P = 0.037). Homozygotes G/G had twice the risk of FM compared to A/A carriers (P = 0.038). FM risk was increased by 12 and 8 times (P<0.001) with comorbidities like depression and sleep impairment. Among patients with FM, the homozygotes A/A were correlated significantly with severe pain intensity (P=0.007).

The investigator concluded links between SNP Val158Met and susceptibility to FM and pain intensity, implying implications of dopaminergic dysfunction in chronic pain vulnerability, urging further investigation into the interaction with COMT enzymatic activity and related FM symptoms.

Source: journals.lww.com/pain/fulltext/9900/the_polymorphism_val158met_in_the_comt_gene_.635.aspx