RNA-primed PCR.

We show that RNA can serve as a primer in PCR. Use of rTth DNA polymerase is essential because it has strong reverse transcriptase activity. RNA primers can be obtained by in vitro transcription and are less costly than DNA primers, which are chemically synthesized. RNA-primed PCR also opens the possibility that a specific amplification reaction can be achieved in the absence of knowledge of the target nucleotide sequence.