CYP2R1 and malignant colon neoplasm: In the Danish “Diet, Cancer and Health” Study, total vitamin D intake did not show a significant relationship with colon cancer risk (IRR = 1.01; 95% CI: 0.87–1.18; vitamin D 2.3 μg/day vs. 10.2 μg/day), but certain genetic variants (CYP2R1 and GC/rs4588) may enhance the protective effect of vitamin D. The combined genetic risk score (GRS) with two risk alleles showed a 10% reduction in colon cancer risk with 3 μg/day of vitamin D intake (IRR = 0.90; 95% CI: 0.81–0.99) [220].