GAPDH and hyperplastic polyp: First, they evaluated the stability of candidate reference genes in saliva using NormFinder and geNorm algorithms and identified GAPDH and TERT as the most stable reference gene and developed a multiplex qPCR method to detect salivary Fn DNA and found that the level of salivary Fn DNA was significantly elevated in CRC patients compared to healthy controls, hyperplastic polyps (HP), and patients with adenomas (Ad).