Fig. 1

HpaII and BstUI restriction fragments. PCR amplicons produced with primer set 32, 40, 50, 54, 63, and 60 were incubated with HpaII or BstUI restriction enzymes, or mock-digested (−). Since PCR amplicons are not methylated, all HpaII and BstUI motifs sites are cleaved. The DNA fragments were separated on an agarose gel and UV-illuminated by ethidium bromide staining. Amplicons produced by primer pair 40 was exclusively cleaved by HpaII; primers 54 and 63 were only cleaved by BstUI; and the amplicons produced by 32, 50, and 66 were cleaved by both HpaII and BstUI. The BstUI cleavage of the amplicon produced by primer pair 32 was calculated to reduce the length with 9 bp. This minor reduction in length may not be visually detectable by agarose gel electrophoresis