Abstract：Two specific detection methods for KRAS G12R and G12S mutations, based on digital PCR and next generation sequencing (NGS), respectively, were established. Taking the advantage of cell lines containing the target KRAS mutation to prepare a different proportion of G12R and G12S mutations, the analysis sensitivity and comparability of the two proposed methods was investigated. It turned out that no significant difference (p>0.05) was observed between NGS and digital PCR when measuring the sample containing mutation ratio over than 0.83%.However, the result analyzed by digital PCR was significantly different (p<0.05) from NGS, when measuring the sample containing mutation ratio less than 0.83%. There was no significant difference between the digital PCR result and the theoretical preparation value.This indicated that the two methods were comparable when analyzing high abundance of KRAS mutation, and digital PCR with higher accuracy is proper applied in the detection of low abundance KRAS mutation.The sensitive of NGS for detection of KRAS mutation is about 1%, whereas digital PCR showed a better sensitivity of 0.02% when analyzing G12S mutation.
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2018, Vol. 39 
