Polymerase chain reaction (PCR) is a technique used to amplify a small quantity of DNA to make millions of copies. PCR is a key tool in molecular biology, but traditional PCR only measures DNA at the end of amplification (endpoint detection), making it hard to quantify accurately. Real-time PCR (RT-PCR) solves this by monitoring DNA amplification throughout its process, using fluorescent dyes or probes. RT-PCR is a key component in biology that helps to identify illnesses such as COVID-19 and Cholera and can also be important to determine water quality. For even more accuracy, digital PCR (dPCR) splits samples so they can be amplified thousands of individual times, giving exact counts of DNA molecules without needing reference standards like in RT-PCR. This makes dPCR ideal for detecting rare genetic changes or low amounts of DNA. This review covers the history and basic principles of this technique, explains RT-PCR, and explains digital PCR.
Keywords: polymerase chain reaction, PCR, digital PCR, dPCR, real-time PCR, RT-PCR