Genetically predicted smoking initiation (OR = 1.167, 95%CI 1.005–1.355, P = 0.043), systemic lupus erythematosus (SLE) (OR = 1.086, 95%CI 1.017–1.160, P = 0.014) and higher CRP (OR = 1.199, 95%CI 1.019–1.410, P = 0.028) were suggestively associated with an increased risk of PBC. The gene discussed is CRP; the disease is primary biliary cholangitis.