Integrative genome-wide analysis unveils the genetic landscape of gallstone disease and highlights novel loci with therapeutic potential.

Objective: Gallstone disease (GD) is a common gastrointestinal disorder with a significant genetic component. Despite known risk factors, the genetic basis of GD remains incompletely understood. We aimed to identify novel genetic loci associated with GD, explore their clinical implications and investigate their therapeutic potential.

Methods: We conducted a genome-wide association study from the UK Biobank followed by a meta-analysis, integrating summary statistics from the FinnGen R11, with further replication from Biobank Japan. Using systematic bioinformatic approaches, we performed gene prioritisation, colocalisation analysis, transcriptome-wide association study, Mendelian randomisations, cross-trait genetic correlations, phenome-wide association study, clinical investigations and gene-environment interactions by leveraging data from the FinnGen, Genotype-Tissue Expression project and Liver Cell Atlas single-cell transcriptomics data set.

Results: Our study highlighted novel susceptibility loci near candidate genes (ie, UGT1A4, FADS1/3) associated with GD, expanding the known genetic landscape. Functional annotation and colocalisation analysis implicated that the independent variants are involved in various hepatocyte functions, including bile secretion, cellular glucuronidation and cholesterol gallstone pathway. Mendelian randomisation established causal relationships between the level of unsaturated fatty acids and GD risk. We also demonstrated the implications of indirect bilirubin level in GD risk stratification and the protective effect of oily fish intake in genetically susceptible individuals.

Conclusions: This study provides new insights into the genetic basis of GD and highlights the role of hepatocytes in GD pathogenesis. These findings have implications for the personalised prevention strategies and new therapeutic interventions in individuals predisposed to GD.