SEPTIN9 and colorectal cancer: Song et al. has demonstrated that methylation of SEPT9 is a highly sensitive biomarker in colorectal cancer (3), eventually developed into an FDA approved clinical test; Epi proColon test (Epigenomics AG) for colorectal cancer screening, which uses real-time PCR on bisulfite-converted plasma cfDNA to determine methylation status of the SEPT9 gene.