Polymerase Chain Reaction from NHGRI

This is an image of polymerase chain reaction from National Human Genome Research Institute (NHGRI). Polymerase chain reaction (PCR) is a fast and inexpensive technique used to "amplify" - copy - small segments of DNA. Because significant amounts of a sample of DNA are necessary for molecular and genetic analyses, studies of isolated pieces of DNA are nearly impossible without PCR amplification. Credit: Darryl Leja and Ernesto del Aguila, NHGRI