We examined the DNA methylation levels of SFRP1, SFRP2, SFRP5, DKK2, DKK3, mir34b/c, RASSF1A, IGFBP7, CDKN2A, and MLH1 in normal colonic crypts isolated from regions that were adjacent to the cancer, as well as distal and proximal regions (left and right sides). Here, DKK2 is linked to cancer.