Figure 2
From: Establishing PNB-qPCR for quantifying minimal ctDNA concentrations during tumour resection
Scheme of the PNB-qPCR. The figure schematically displays the process of the PNB-qPCR with a hypothetical template containing an average of three mutated KRAS copies (in red) per PCR in a background of WT DNA (black). The mutated fraction is effectively enriched about 1000-fold. The additional pooling step of five first round products guarantees more accurate quantification in subsequent specific second round amplifications. It reduces variance in target template concentration following first round PCR, especially if low copy numbers of KRAS mutations had been present in the starting material.
