In a MR analysis among 28,144 T2D cases and 76,344 controls, we previously used 4 prior GWAS-discovered genetic variants (at GC, CYP2R1, DHCR7, and CYP24A1) as genetic instruments, and found a null association between 25(OH)D and T2D (OR 1.01 [95% CI 0.75, 1.36] per 1-SD reduction in 25(OH)D) [1]. Here, DHCR7 is linked to type 2 diabetes mellitus.