U.S. flag

An official website of the United States government, Department of Justice.

Crime Scene and DNA Basics for Forensic Analysts

Polymerase Chain Reaction (PCR)

Home  |  Glossary  |  Resources  |  Help  |  Contact Us  |  Course Map

In 1983, Kary Mullis developed the technique known as the polymerase chain reaction (PCR), 03 which ultimately revolutionized molecular biology, including forensic DNA analysis. Through PCR, forensic DNA analysis essentially became more rapid and sensitive.  The problems of analysis time, use of radioactive materials, large sample size, presence of un-degraded high molecular weight DNA, and the need to deal with sizing variations were all dealt with by the various PCR techniques.

Read more about Quantitative PCR in course: DNA Extraction & Quantitation.

(You may have to enter your Userid and password.)

One of the first forensic PCR tests was based on identification of human leukocyte antigen (HLA). The HLA markers are proteins of known sequence; the genes coding for each antigen can be identified. A PCR-based assay for one of the HLA loci, DQ-Alpha, was developed in 1991 and was used in crime laboratories. The kit, developed by the Cetus Corporation and marketed by Roche, was simple to use and required minimal equipment.


Back Forward