BNA^NC clamp PCR for simple and sensitive detection of KRAS and EGFR mutations

2',4'-BNA^NC (BNA^NC)-modified oligonucleotides, which have excellent binding affinity to complementary RNA and DNA strands and high nuclease resistance, were successfully used to develop a new clamp polymerase chain reaction (PCR) method for detecting trace amounts of mutant DNA in the presence of excess wild-type DNA. The BNA^NC clamp oligonucleotides (BNA^NC clamps) showed excellent clamping ability compared with conventional clamp oligonucleotides, enabling highly sensitive detection of various kinds of KRAS and EGFR gene mutations.