The pathogenesis of inflammatory bowel disease (IBD) is complex, and traditional observational studies cannot easily avoid confounding factors to establish robust causal relationships. As an emerging genetic analytical approach, Mendelian randomization(MR) uses genetic variations as instrumental variables, which provides a novel perspective for exploring the etiology and pathogenesis of IBD. This review systematically summarizes research progress on MR in exploring the pathogenesis and precision therapy of IBD, and focuses on the role of MR in identifying environmental risk factors for IBD, elucidating pathogenesis, clarifying comorbid associations, and exploring therapeutic targets, to provide crucial evidence for elucidating disease characteristics and open new research pathways for drug development and precision therapy.

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