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Polymerase Chain Reaction (PCR): Specialised Reactions

  1. Stella E Tsirka,
  2. Michael A Frohman

Published Online: 19 APR 2010

DOI: 10.1002/9780470015902.a0003152.pub2



How to Cite

Tsirka, S. E. and Frohman, M. A. 2010. Polymerase Chain Reaction (PCR): Specialised Reactions. eLS. .

Author Information

  1. State University of New York, Stony Brook, New York, USA

Publication History

  1. Published Online: 19 APR 2010

This is not the most recent version of the article. View current version (15 SEP 2014)


The polymerase chain reaction (PCR) is a technique that rapidly amplifies selected subsets of DNA (deoxyribonucleic acid) or complementary DNA (cDNA) from initially complex biological mixtures. The efficiency of amplification or sequence of the amplified material can then be examined for any of many purposes, including genotyping or the characterisation of new genes, gene expression patterns, mutations or polymorphisms. Quantitative-PCR (QT-PCR) has become practical and popular over the past decade with the generation of libraries of individual primer sets and arrayed sets of primers by commercial entities. QT-PCR machines can assay up to 384 samples at once, permitting the complete analysis of expression of families of genes, such as signalling kinases or cytokines, in a single experiment. RACE (rapid amplification of cDNA ends)-PCR has also become popular to identify microRNAs (ribonucleic acid). PCR is highly useful in structural biology to rapidly modify the boundaries of protein domains intended for crystallisation.

Key Concepts:

  • PCR can be conducted on vanishingly small amounts of material.

  • PCR can be used for rapid genotyping or sequencing.

  • PCR is useful for quantitative analysis of gene expression of entire gene families or signalling networks in arrayed assays.

  • PCR is frequently the method of choice for genetic engineering involving mutations, truncations or extensions of existing genes.


  • RT-PCR;
  • molecular biology;
  • polymorphisms;
  • genotyping