This essay on the polymerase chain reaction is one of a series developed as part of FASEB's efforts to educate the general public, and the legislators whom it elects, about the benefits of fundamental biomedical research-particularly how investment in such research leads to scientific progress, improved health, and economic well-being.

Quantitative PCR assays are now the standard method for viral diagnostics. These assays must be specific, as well as sensitive, to detect the potentially low starting copy number of viral genomic material. We describe a new technique, polymerase chain displacement reaction (PCDR), which uses multiple nested primers in a rapid, capped, one-tube reaction that increases the sensitivity of normal q...

The polymerase chain reaction (PCR) is a powerful and widely used technique that has greatly advanced our ability to analyze genes. Genomic deoxyribonucleic acid (DNA) present in cells contains many thousands of genes. This makes it difficult to isolate and analyze any individual gene. PCR allows specific DNA sequences, usually corresponding to genes or parts of genes, to be copied from genomic...

PCR depends on generation of a deoxyoligonucleotide complementary to the known 3' terminus of the portion of DNA to be amplified. This is then annealed with the appropriate strand of heat-denatured DNA and used as a primer for synthesis by a DNA polymerase of a full-length complementary strand (Fig. 1). The two strands are then separated by heat denaturation and the process repeated. However, i...