Establishment of a nested-ASP-PCR method to determine the clarithromycin resistance of Helicobacter pylori

Figure 1 PCR products of wild-type Helicobacter pylori strain in gastric mucosa. A: PCR product amplified with the external primers (M: 1000 bp DNA marker, N: Helicobacter pylori negative sample, 1: Wild-type strains); B: PCR products amplified with the different inner primers; C: The products amplified by nested-ASP-PCR [M: 1000 bp DNA marker (1000, 750, 500, 400, 300, 200, 100), W2: 2142 wild-type primers (2142A), M2: 2142 mutation primers (2142G), W3: 2143 wild-type primers (2143A), M3: 2143 mutation primers (2143G), W4: 2144 wild-type primers (2144A), M4: 2144 mutation primers (2144G)]. ASP-PCR: Allele-specific primer-polymerase chain reaction.