UGT1A1 and lung cancer: In stratified analyses, genetically raised bilirubin levels predicted by the non-UGT1A1 SNPs, but not the UGT1A1 SNP, were inversely associated with lung cancer risk among individuals who ever smoked, squamous cell, and small cell lung cancer subtypes with ORs equal to 0.86; 95% CI 0.76–0.96, 0.85; 95% CI 0.73–0.99, and 0.77; 95% CI 0.61–0.97, per 1-SD increment, respectively (Figure 1B).