title: Label/Quencher-Free Detection of Exon Deletion Mutation in Epidermal Growth Factor Receptor Gene Using G-Quadruplex-Inducing DNA Probe.
abstract: Detection of exon 19 deletion mutation in the epidermal growth factor receptor (EGFR) gene, which results in increased and sustained phosphorylation of EGFR, is important for diagnosis and treatment guidelines in non-small-cell lung cancer. Here, we have developed a simple and convenient detection system using the interaction between G-quadruplex and fluorophore thioflavin T (ThT) for discriminating EGFR exon 19 deletion mutant DNA from wild type without a label and quencher. In the presence of exon 19 deletion mutant DNA, the probe DNAs annealed to the target sequences were transformed into G-quadruplex structure. Subsequent intercalation of ThT into the G-quadruplex resulted in a light-up fluorescence signal, which reflects the amount of mutant DNA. Due to stark differences in fluorescence intensity between mutant and wild-type DNA, we suggest that the induced G-quadruplex structure in the probe DNA can report the presence of cancer-causing deletion mutant DNAs with high sensitivity.
authors: Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea.
authors: Hyo Ryoung
authors: HR
authors: Kim
authors: Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea.
authors: Il Joon
authors: IJ
authors: Lee
authors: Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea.
authors: Dong-Eun
authors: DE
authors: Kim
keywords: EGFR exon 19 deletion; G-quadruplex; hairpin DNA; thioflavin T