There was a highly significant difference (p < 0.001) between the cancer group and control groups 1 + 2 with regard to hypermethylation frequency of ten genes (APC, BMP3, BNC1, MESTv2, NPTX2, RASSF1A, SFRP1, SST, TFPI2 and TAC1) (Table 4) and significant difference (p < 0.05) in seven other genes (ALX4, ESR1, HIC1, RARB, SFRP2, SEPT9v2 and WNT5A) (Table 4). Here, SFRP1 is linked to cancer.