Fig 4. Separate method and pre-existing mismatches.

The Separate method separately amplifies the coding and non-coding strands. The aliquot on the left-hand side only amplifies the top strand, while the aliquot on the right-hand side only amplifies the bottom strand. The yellow rectangles indicate strands that are not primer extension products and are removed by exonucleases. For the original molecule shown with a pre-existing U:G mismatch, the Separate method detects a C>T mutation on the left-hand side and no mutation on the right-hand side.