Figure 5. To avoid interference from wild-type gene signals, no wild-type gene were added to the mutant targets to verify the universality of LNA-mediated real-time PCR for the detection of EGFR point mutations. The amplification comparison between the LNA system and the normal PCR system (without LNA clamp) was assessed in the samples that contained 10000 copies of wild-type DNA (from A549 cells) and 100 and 10 copies of mutant DNA, respectively. Plasmids harboring (A) the G719A, (B) T790M, (C) S768I, and (D) L858R mutant sequence was directly amplified in each system. (E) Agarose gel electrophoresis of amplicons in both systems, 1(LNA free-10000 wt), 2(LNA-10000 wt), 3(LNA free-100 mut), 4(LNA-100 mut), 5(LNA free-10 mut), 6(LNA-10 mut), 7 (negative control).