Subgroup analysis by cancer site showed that hypermethylation of VDR at significant CpG sites was inversely associated with both colon cancer risk (aOR, 0.32; 95% CI, 0.16–0.64; P = 0.001) and rectal cancer risk (aOR, 0.26; 95% CI, 0.12–0.57; P = 0.001) (Pheterogeneity = 0.65) (Fig. 2). This evidence concerns the gene VDR and rectal cancer.