Introduction to Polymerase Chain Reaction

The polymerase chain reaction (PCR) has become an indispensable tool of molecular biology (1 –5 ). Since its discovery in 1985 the process has found its integration into all research areas involving the use of DNA and RNA. Using this technique, a small starting sample of DNA or RNA can be used to amplify a specific DNA or RNA target over a million-fold in as little as 2 h. This allows for the detection of as little as a single copy of a gene or part of a gene in cells, whether they be from blood, cultured cells, tissue biopsies, chromosomes, or any other biological system that contains DNA or RNA, including archival materials (formalin-fixed, paraffin-embedded).