National Cancer Institute (source definition)
Polymerase Chain Reaction
A method for amplifying a DNA base sequence using multiple rounds of heat denaturation of the DNA and annealing of oligonucleotide primers complementary to flanking regions in the presence of a heat-stable polymerase. This results in duplication of the targeted DNA region. Newly synthesized DNA strands can subsequently serve as additional templates for the same primer sequences, so that successive rounds of primer annealing, strand elongation, and dissociation produce rapid and highly specific amplification of the desired sequence. PCR also can be used to detect the existence of the defined sequence in a DNA sample.
Review and references
Automated source check (NCI definition)
2026-10-18
2026-10-19
professional use
References
- NCI Thesaurus 26.09d — Polymerase Chain Reaction (C17003)
- Source: National Cancer Institute, NCI Thesaurus 26.09d, C17003. NCI definition, reproduced without modification under CC BY 4.0.
- Tongue Swab Mycobacterium tuberculosis Quantitative Polymerase Chain Reaction for Community Screening of Asymptomatic Tuberculosis Versus Clinic-Based Triage of Symptomatic Tuberculosis. — Clin Infect Dis, 2026-10-09 (PMID 42850580; literature)
What it is
A method for amplifying a DNA base sequence using multiple rounds of heat denaturation of the DNA and annealing of oligonucleotide primers complementary to flanking regions in the presence of a heat-stable polymerase. This results in duplication of the targeted DNA region. Newly synthesized DNA strands can subsequently serve as additional templates for the same primer sequences, so that successive rounds of primer annealing, strand elongation, and dissociation produce rapid and highly specific amplification of the desired sequence. PCR also can be used to detect the existence of the defined sequence in a DNA sample.
Source: National Cancer Institute, NCI Thesaurus 26.09d, C17003. NCI definition, reproduced without modification under CC BY 4.0.
Source identity and definition checked automatically on 2026-10-18. No individual clinical interpretation or human reviewer is asserted.
Compliance note
Reference intervals and interpretation depend on the laboratory, specimen, method and clinical context. This source definition is educational information; it does not establish a diagnosis, product approval or suitability for an individual.