Sex differences in chronic pain linked to genetics

Differences in chronic pain experienced by men and women are likely to have a genetic basis, results of a genome wide association study (GWAS) published in PLOS Genetics have suggested (8 April 2021)​[1]​.

Researchers looked for genetic variants associated with chronic pain in 209,093 women and 178,556 men who were participants in the UK Biobank, a large-scale biomedical database and research resource.

They discovered 31 genes associated with chronic pain in women and 37 genes associated with chronic pain in men. Just 1 gene was associated with chronic pain in both sexes.

The researchers also examined whether these genes were up- or down-regulated in tissues known to be associated with chronic pain. They reported that all 37 genes in men and all but one of the 31 genes in women were expressed in the dorsal root ganglion, a cluster of nerves in the spinal cord that transmit pain signals from the body to the brain.

There was also enriched gene expression in sex-specific tissues. The researchers said their findings indicated the existence of potential sex differences in chronic pain at the single nucleotide polymorphism-, gene- and transcript abundance-level, and that the data supported theories of strong nervous system and immune involvement in chronic pain in both sexes.

Lead author Keira Johnston, a doctoral student at the Institute of Health and Wellbeing, University of Glasgow, Scotland, said: “Our study highlights the importance of considering sex as a biological variable and showed subtle but interesting sex differences in the genetics of chronic pain.”

The researchers concluded: “These findings may inform development of novel treatment approaches in future.”