Fig. 2
SNP detection. PNA melting point differences between perfect match and mismatch(es) were measured by melting point analysis. a Melting points of PNA probe and target oligonucleotide containing one to four mismatches (SNP_1probe). b Melting points of PNA probe containing FAM (blue line, SNP_2probe), HEX (green line, SNP_3probe), Texas-Red (red line, SNP_4probe), or Cy5 (violet line, SNP_5probe) fluorescence were analyzed after PCR cycles in closed well reactions. c) Melting points of synthetic DNA target with varied percentages (from 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 to 100 %) of the mutation type of single mismatch relative to the perfect match templates using SNP_3probe. Both perfect match and single mismatch templates were artificially synthesized and start copies were roughly 2 × 106 copies per reaction. PM, perfect match; 1MM, 1 nucleotide mismatch; 2MM, 2 nucleotides mismatch; 3MM, 3 nucleotides mismatch; 4MM, 4 nucleotides mismatch; NTC, non-template control