PCR, qPCR, & DNA Amplification

Overview & Resources

Polymerase chain reaction (PCR) is a rapid and inexpensive in vitro technique used to amplify copies of small segments of DNA, producing billions of DNA copies quickly and efficiently. Since its introduction in the 1980’s by Kary Mullis, it has significantly contributed to various innovations in molecular biology, biotechnology, and biopharmaceuticals, resulting in the development of numerous technologies.

PCR has several applications in molecular biology and beyond, including:

• Selective DNA Isolation
• Medical and Diagnostic uses
• Genetic research, cloning, and analysis
• DNA Fingerprinting
• Food Safety

PCR assays are also used to detect, provide diagnostic analysis, and sequence viral genomes. For example, a variant of PCR, reverse transcription (RT-PCR), has been used extensively to test patients for COVID-19 infections from the SARS-CoV-2 viral genome.

There are several types of PCR used today, some of which include:

• qPCR
• RT-qPCR
• dPCR
• ddPCR
• Hot-start PCR
• High fidelity PCR
• Multiplex PCR
• Microfluidic PCR

To facilitate polymerase chain reaction, thermal cyclers, also referred to as PCR machines or PCR systems, were developed to provide a thermally controlled environment for the DNA or RNA sample by using a heating block to maintain different temperatures for a specific time and duration. The heat and various temperatures provided made it possible to break up DNA strands during the denaturing stage of PCR. 

Learn more about polymerase chain reaction and the consumables required to perform this DNA amplification technique below.