ABSTRACT
The plateau probably occurs because of a variety of factors. Foremost of these is the eventually overwhelming excess of template over DNA polymerase. Polymerase chain reaction reagents should be handled carefully to prevent degradation. The most sensitive reagents are the enzymes, for example, reverse transcriptase, RNase inhibitor, and DNA polymerases. Several perspectives guide the design of primers, the first of which is the target to be amplified. The target region should be checked for its intra-strand complementarity, that is, its ability to form stable hairpin structures that would interfere with the progress of DNA polymerase. The duplexes are extended by Taq polymerase because this enzyme retains a fair amount of activity even at temperatures as low as 22°C and thus extraneous products almost certainly appear at these lower annealing temperatures.
