Polymerase Chain Reaction

The Polymerase Chain Reaction (or PCR) is a laboratory technique which greatly amplifies the amount of a short segment of DNA. It is based on the process by which DNA is copied in cells. Since replicated DNA is itself available for later replication, the PCR process can feed upon itself, leading to an accelerating increase to millions of copies over the original DNA sample.Polymerase Chain Reaction Polymerase Chain Reaction
PCR solves two of the major problems encountered in the analysis of DNA in an organism. The first problem is specificity - an area of interest may be as little as one unit of DNA among billions. Since PCR only amplifies a small segment (leaving the rest of the DNA largely unaltered), the required specificity of a later genetic assay might be reduced to just one part among hundreds. The second problem is sensitivity - a sample of DNA might contain just a few copies of an area of interest. By increasing that to millions (or billions) of copies, PCR greatly speeds or simplifies later genetic analysis.
PCR has become a widely used tool for research in molecular genetics. It is also the basis for medical genetic testing, where individuals are screened for the presence of disease mutations. DNA Fingerprinting, the unique identification of individuals by patterns of variation in their DNA, is also based on PCR, and is used in criminal forensics and parental testing. The technique had such widespread impact that its inventor was awarded the Nobel Prize in 1993, just eight years after it was first reported