ABSTRACT
Does it really work? It is so simple! Why did I not think of it? These thoughts were probably typical of most molecular biologists on reading early reports of the polymerase chain reaction or PCR as it is more commonly called. PCR uses a few basic components, ones that we use in the laboratory every day to make large numbers of copies of a specific DNA fragment in a test-tube. PCR has been called a ‘DNA photocopier’. Although apparently simple, PCR is a complicated process with many reactants. Some are present at very low initial concentrations (template) which increase dramatically as the reaction proceeds, others are at concentrations that hardly change during the reaction (dNTPs, primers). There are significant changes in temperature and pH and therefore dramatic fluctuations in the dynamics of a range of molecular interactions. So PCR is really a very complex process, but one with tremendous power and versatility for DNA manipulation and analysis.
