While real-time PCR (RT-PCR) is designed for amplification of DNA, using a reverse transcriptase enzyme (RTE) allows amplification from an RNA target by creating a copy of DNA from the original RNA molecule. The PCR process is modified for the amplification of RNA by the addition of a RTE in the assay components. RTE creates a copy of DNA using the original RNA specimen. Although there are thermostable polymerases that have reverse transcriptase capabilities, they are not commonly used.
Reverse transcriptase PCR is used for the detection of viruses, such as HIV, hepatitis C virus (HCV), and Influenza, that have an RNA genome. Reverse transcriptase PCR methods provide early detection of infection, even before the formation of antibodies. Therefore, it is a particularly useful method for HIV and HCV detection in blood bank nucleic acid testing.
Reverse transcriptase PCR is commonly performed using real-time PCR (RT-PCR).