CYP2R1 and cancer: However, a more recent and larger MR analysis in UK Biobank (438,870 participants, 6,998 cancer deaths) found little evidence that circulating vitamin D (instrumented using 5 SNPs in GC, CYP2R1, DHCR7, or CYP24A1) influenced cancer mortality [OR per 20 nmol/L higher plasma 25(OH)D: 0.97; 95% CI 0.84, 1.11] [58].