Multiomics analyses prioritize disease genes and pathways in hidradenitis suppurativa

Hidradenitis suppurativa is a chronic inflammatory skin condition associated with an increased risk of all-cause mortality. Although it is known to be influenced by genetic and environmental factors, the genetic contributors remain poorly characterized. We performed a large-scale meta-analysis involving patients from the Million Veteran Program, UK Biobank, and FinnGen, including a total of 3941 cases and 1,435,603 controls. We identified 9 genome-wide significant loci, 5 of which have not been previously reported. Using a variant-to-gene analysis pipeline, we mapped these variants to 11 lead genes, supporting prior candidates while revealing previously unreported ones, to our knowledge, including SMPD4 and PSMA4, which we demonstrate are differentially expressed in hidradenitis suppurativa skin lesions. Using expression quantitative trait loci and protein quantitative trait loci, 2-sample Mendelian randomization identified additional genes likely involved in the pathogenesis of hidradenitis suppurativa, including MPO. We subsequently probed the protein interactome network of these candidates to reveal drug targets for prioritization in future studies. These results reaffirm the previously suspected role of KLF5 in hidradenitis suppurativa while linking the pathogenesis of the disease to pathways related to lipid and skin barrier homeostasis, proteasome function, and oxidative stress.