PCR or the Polymerase Chain Reaction has become the cornerstone of modern molecular biology the world over. Real-time PCR is a novel application of the Polymerase Chain Reaction that maximizes the potential of the technique.

To understand Real Time PCR it’s easier to begin with the principles of a basic PCR

Principles of PCR

PCR is a technique for amplifying DNA. There are 2 reasons why you may want to amplify DNA. Firstly you may want to simply create multiple copies of a rare piece of DNA. For example a forensic scientist may want to amplify a tiny piece of DNA from a crime scene. More commonly however you may wish to compare 2 different samples of DNA to see which is the more abundant. Because DNA is microscopic you cannot see which sample contains the most DNA. However, if you amplify both samples at the same rate, you can calculate which sample contained the higher starting copy number. With standard PCR this is done after all amplification cycles have been completed (end point analysis). This can be done by visualizing the PCR product on a gel and measuring the amount of DNA that has been produced……………………