Polymerase Chain Reaction (PCR) and its Applications
Polymerase Chain Reaction (PCR) PCR is an enzymatic process in which a specific region of DNA is replicated over and over again to yield many copies of a particular sequence. This method combines the principles of complementary nucleic acid hybridization with those of nucleic acid replication applied repeatedly through numerous cycles. The most widely used target nucleic acid amplification method is the polymerase chain reaction (PCR). This method is able to amplify a single copy of a nucleic acid target, often undetectable by standard hybridization methods, and multiply to 10 7 or more copies in a relatively short period. This thus provides ample target that can be readily detected by numerous methods. APPLICATIONS OF PCR PCR can amplify a single DNA molecule from a complex mixture, largely avoiding the need to use DNA cloning to prepare that molecule. Variants of the technique can similarly amplify a specific single RNA molecule from a complex mixture. DNA sequencing has be...