RNA template-specific polymerase chain reaction (RS-PCR): a novel strategy to reduce dramatically false positives.

We report a novel modification of the reverse transcription-polymerase chain reaction method that we have dubbed RNA template-specific PCR (RS-PCR). With this approach, the 5' end of the first strand is tagged with a unique nucleotide sequence during reverse transcription which may then be exploited to amplify preferentially RNA-derived sequences. In our hands, RS-PCR greatly reduces the frequency of false positives and virtually eliminates carryover contamination from DNA fragments amplified in previous experiments.