Britannica Sources used in this answer

How did the polymerase chain reaction change the study of DNA?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

A step-by-step diagram shows donor DNA and vector DNA cut with restriction enzymes to create overhangs, mixed and sealed with ligase to form recombinant DNA, which is introduced into bacterial cells. The recombinant DNA replicates as the cells divide, producing clones. — biotechnology Steps involved in the engineering of a recombinant DNA molecule.

The development of the polymerase chain reaction (PCR) revolutionized the study of DNA by providing a fast, accurate, and automated method to amplify specific genetic sequences. Before its invention by Kary B. Mullis in 1983, generating sufficient quantities of DNA for analysis was a labor-intensive and time-consuming process.12

PCR transformed DNA research in several key ways:

Efficiency and Scale: It allows researchers to produce billions of copies of a DNA fragment in just a few hours, even when starting with as little as a single molecule of template DNA.12
Versatility: The technique works with small or partially degraded samples, making it invaluable for forensic science, where it is used to generate DNA profiles from trace evidence like hair or blood.13
Medical and Scientific Advancement: PCR has become a cornerstone of molecular biology, enabling precise genetic testing, the diagnosis of infectious diseases, and the study of ancient DNA from fossilized remains.12
Technological Integration: By facilitating the production of adequate DNA quantities, PCR has significantly accelerated DNA sequencing and mapping efforts, such as the human genome project.3