Unique features of the self-sustained sequence replication (3SR) reaction in the in vitro amplification of nucleic acids.

The development of a transcription-based amplification system and its application to a retrospective analysis of HIV-1-infected clinical samples demonstrated the specificity and sensitivity of this in vitro amplification procedure. The TAS protocol has been modified to mimic the retroviral strategy of replication, resulting in a self-sustained sequence replication (3SR) amplification reaction which operates under isothermal conditions (37 degrees C). The ability to specifically amplify only RNA sequences in the presence of DNA genomic copies containing the same sequence and the rapid kinetics of the 3SR reaction distinguish it from the well-used PCR protocol.