Alternatively, specificity may be achieved by using additional PCR markers such as methylated septin 9 or ELISA-based assays with colon-cancer-specific-2 or TIMP 1 (Holten-Andersen et al, 2002; Leman et al, 2008; deVos et al, 2009; Church et al, 2010) proteins, allowing combinations similar to the CEA results in our study, and offering the prospect of a more specific blood test screen for colorectal cancer. Here, SEPTIN9 is linked to colorectal cancer.