ABCB1 and cancer: Recently, we have demonstrated that carriers of the variant allele of MDR1 intron 3 (G-rs3789243-A) were at 1.54-fold higher risk of colorectal cancer than homozygous wild type carriers (95% CI: 1.13–2.08) in a case-cohort study nested in the prospective Danish Diet, Cancer and Health cohort study (V. Andersen et al, submitted).