One study identified 4 potential methylation markers (COL4A1, COL4A2, TLX2, and ITGA4) upregulated in CRC patients’ stool, using real-time methylation-specific PCR based on TaqMan probe fluorescence (TaqMan qMSP) technology after a selection of these genes in CRC cell lines and CRC patients’ tissue [59]. The gene discussed is COL4A1; the disease is colorectal carcinoma.