Polymerase chain reaction

Polymerase Chain Reaction’s Mark on Science

Advances in science and technology come at an ever increasing pace. One of these advances is the polymerase chain reaction, which makes it possible toamplify a piece of DNA, making multiple copies. Polymerase chain reaction has greatly benefited science through its use in research and medicine for genetic mapping and the early detection ofhereditary and other diseases.
Before the development of PCR, genetic fingerprinting, or the detection of genetic variation proved to be a very tedious and difficult process. It is not easy to distinguishbetween two alleles at a specific location of the human genome, which consists of billions of base pairs. Before, scientists had to rely on arduous approaches such as restriction fragment lengthpolymorphism analysis, where DNA is cut using restriction enzymes and its fragments compared using gel electrophoresis. Once developed, however, PCR “allowed the extraction of a specific locus of the genomeand produced sufficient quantities of it for further analysis” (Bustin, 276). This is done through the use of DNA oligonucleotide primers which attach to the specific denatured locus desired. Taqpolymerase is then used to copy the DNA sequence. Multiple copies can be made using the same polymerase by carrying out multiple heating and cooling cycles (Polymerase). PCR made genetic studies a loteasier: “With PCR… the complexity of the problem is reduced to one that involves DNA fragments that are just a few hundred base pairs in length. Given the small DNA size, multiple allelic discriminationmethods can be used to produce genotype information” (Bustin 277). This breakthrough proved to be a blessing to forensic science as well. Now, faint traces of DNA found at a crime scene can beamplified and compared to the DNA of the suspects, thus making law enforcement a much easier and accurate task.
PCR has also greatly benefited the medical field. It can be used for a variety of...