Genome-wide analysis of 944,133 individuals provides insights into the etiology of hemorrhoidal disease

Hemorrhoidal disease (HEM) affects a large fraction of the population but its etiology including suspected genetic predisposition is poorly understood. We conducted a GWAS meta-analysis of 218,920 HEM patients and 725,213 controls of European ancestry, demonstrating modest heritability and genetic correlation with several other diseases from the gastrointestinal, neuroaffective and cardiovascular domains. HEM polygenic risk scores validated in 180,435 individuals from independent datasets allowed the identification of those at risk and correlated with younger age of onset and recurrent surgery. We identified 102 independent HEM risk loci harboring genes whose expression is enriched in blood vessels and gastrointestinal tissues, and in pathways associated with smooth muscles, epithelial and endothelial development and morphogenesis. Network transcriptomic analyses of affected tissue from HEM patients highlighted HEM gene co-expression modules that are relevant to the development and integrity of the musculoskeletal and epidermal systems, and the organization of the extracellular matrix. We conclude HEM has a genetic component that predisposes to smooth muscle, epithelial and connective tissue dysfunction.