Group 1 preliminarily verified the clinical relevance of the selected CpG sites in sDNA, and the methylation levels of SFRP2‐1, SDC2‐1, SDC2‐3, SDC2‐5, and SDC2‐6 were different between normal individuals and CRC patients (Figure 5a). This evidence concerns the gene SFRP2 and colorectal carcinoma.