Abstract:Objective:To apply a fluorescent nucleotide dye Sybr Green I in detecting telomerase activity and assess its clinical value in the diagnosis of colorectal carcinoma. Methods:Telomerase activity was measured by telomeric repeat amplification protocol (TRAP) combined with fluorescent nucleotide dye Sybr Green I in 46 cases of colorectal carcinoma tissue specimens and 19 tumor-adjacent tissue specimens. Results: Telomeric repeat amplification product was displayed as clear bands in PAGE stained with Sybr Green I; the positive rate of telomoerase activity in colorectal carcinoma tissue was 89.13%, whereas no telomerase activity was observed in 19 tumor-adjacent tissue specimens. There was no relationship between telomerase activity and the level of cell differentiation, Dukes stages, or metastasis of lymph nodes. Conclusions: The method of TRAP combined with Sybr Green I to determine telemerase activity is an important method for the diagnosis of colorectal carcinoma.