Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 3 complete abstracts (761 words), 9 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Polymerase Chain Reactions; Reaction, Polymerase Chain; Reactions, Polymerase Chain; PCR; Anchored PCR; PCR, Anchored; Anchored Polymerase Chain Reaction; Inverse PCR.
Where it fits in the MeSH classification
- Broader topics
- Nucleic Acid Amplification Techniques
- Narrower topics
- Amplified Fragment Length Polymorphism Analysis; Multiplex Polymerase Chain Reaction; Primed In Situ Labeling; Random Amplified Polymorphic DNA Technique; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction
- See also
- Sequence Tagged Sites; Ligase Chain Reaction
Research landscape
PubMed indexes 477,306 records tagged with the MeSH heading “Polymerase Chain Reaction” (counts retrieved 2026-10-29). 29,840 of them (6.3%) were published from 2020 onward, and the busiest period so far is 2000-2009 with 185,350 records.
Reviews account for 10,648 records (2.2%) and meta-analyses for 546. Randomized controlled trials number 2,044 (0.4%) as a share of all records on the topic. Randomized trials make up only a small share of this literature, so much of what is known comes from laboratory, observational or descriptive work.
Show the data
| Period | Records |
|---|---|
| through 1999 | 86,636 |
| 2000-2009 | 185,350 |
| 2010-2019 | 175,480 |
| 2020 onward | 29,840 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 10,648 | 2.2% |
| Meta-analyses | 546 | 0.1% |
| Randomized controlled trials | 2,044 | 0.4% |
Method: PubMed query "Polymerase Chain Reaction"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-29.
Reading the evidence in genetics and genomics
Genetic findings vary widely in strength. A variant linked to a condition in one study may not replicate in other ancestries, and most common variants have small effects that are meaningful only in aggregate. Studies of rare, high-impact variants can support strong causal claims about a gene, while association studies describe statistical links that need functional and independent replication. Check the sample size, the ancestry of participants, whether results were replicated, and whether a laboratory or clinical outcome was actually measured.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Diagnostic concordance of dermatopathology and PCR in differentiating eczema from psoriasis | 2026 | Research article Design not recorded in structured metadata | 6 | cc by PMID 41814865 · DOI · PMC13308667 |
| A qPCR identification scheme to differentiate actinomycetoma from eumycetoma | 2026 | Research article Design not recorded in structured metadata | 2 | cc by PMID 42360550 · DOI · PMC13676668 |
| Q4ddPCR: a flexible, 4-target assay for high-resolution HIV reservoir profiling | 2026 | Research article Design not recorded in structured metadata | 2 | cc by PMID 41720775 · DOI · PMC13035820 |
Diagnostic concordance of dermatopathology and PCR in differentiating eczema from psoriasis [1]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundTargeted treatments for non-communicable chronic inflammatory skin diseases like eczema and psoriasis offer significant potential for effective therapy.
- Closing excerpt
- By reducing diagnostic ambiguity, it enhances clinical confidence and supports more precise and timely therapeutic decisions in inflammatory skin disease management.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (275 words)
BackgroundTargeted treatments for non-communicable chronic inflammatory skin diseases like eczema and psoriasis offer significant potential for effective therapy. However, therapeutic success requires an accurate diagnosis, which is challenging due to their overlapping clinical and histological features.ObjectivesWe aimed at assessing the diagnostic performance of both a manual (MC) and fully automated (PsorX-LabDisk) quantitative real-time polymerase chain reaction (RT-qPCR) test based on the expression of NOS2 and CCL27 compared with conventional dermatopathological evaluation in differentiating psoriasis from eczema.MethodsSeventy-three formalin-fixed, paraffin-embedded skin samples of psoriasis and eczema were randomly selected and evaluated histopathologically (H&E-stained sections) by 14 dermatopathologists to assess inter-observer variability, quantified using Cohen's and Fleiss' κ. To confirm that the observed variability was not cohort- or rater-specific, a validation cohort (n = 72) from an independent institution was assessed by three dermatopathologists under identical conditions. For molecular analysis, both manual (MC) and automated NOS2/CCL27-based RT-qPCR (PsorX-LabDisk) workflows were applied. Diagnostic performance (sensitivity, specificity, accuracy) of histopathological and molecular analyses was determined against reference diagnoses.ResultsDermatopathological evaluation demonstrated only fair agreement (Fleiss' κ = 0.31) in both study and validation cohort. The mean diagnostic accuracy of dermatopathology was 76.9%, with a sensitivity of 70% and specificity of 81.6%. In comparison, MC and the PsorX-LabDisk achieved sensitivities of both 92.9%, specificities of 82.2% and 84.4% and accuracies of 87.7% and 86.3%, respectively. In diagnostically ambiguous cases, molecular testing maintained high accuracy (>86%), clearly outperforming dermatopathology, which showed near-random agreement and low accuracy (61.7%).ConclusionsBoth MC and PsorX-LabDisk provide a reliable, examiner-independent complement to dermatopathology for differentiating psoriasis and eczema. By reducing diagnostic ambiguity, it enhances clinical confidence and supports more precise and timely therapeutic decisions in inflammatory skin disease management.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41814865 · DOI · PMC13308667
A qPCR identification scheme to differentiate actinomycetoma from eumycetoma [2]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundMycetoma is a Neglected Tropical Disease of the skin.
- Closing excerpt
- With hand-held qPCRs this can also be performed in the field.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (286 words)
BackgroundMycetoma is a Neglected Tropical Disease of the skin. It is characterized by large tumorous lesions in the subcutaneous tissue which hinder the patients in their daily activities. The disease can be caused by either bacteria (actinomycetoma) or fungi (eumycetoma), and treatment depends on the entity. Therefore, in 2022, a Target Product Profile was published by the World Health Organisation in which it was stated that there is an urgent need to develop a diagnostic tool that can differentiate the two reliably within a day.ObjectivesTo develop a qPCR that can not only differentiate actinomycetoma from eumycetoma but can also identify the actinomycetoma causative agents to the genus level.MethodsWe developed singleplex, quadruplex and triplex qPCRs that can be used, depending on the endemic region and validated this against a large strain collection and grains.ResultsThe limit of detection (LOD) of each of the probes ranged from 0.000002 ng for the fungal probe to 0.002 ng for the Nocardia genus probe in a singleplex reaction. Higher LODs were obtained in the multiplexes. The sensitivity and specificity were both 100% for most combinations, although some cross-reactivity with the Actinomadura and Streptomyces genus probes was noted, mainly with non-mycetoma causative agents.ConclusionThe developed qPCR meets the requirements set in the Target Product Profile from the World Health Organisation.ImportanceIn this study a qPCR is developed which can differentiate actinomycetoma from eumycetoma and identify actinomycetoma causative agents to the genus level. This qPCR adheres to the minimal requirements set in the Target Product Profile for a mycetoma diagnostic test by the World Health Organisation. When the qPCR is used on mycetoma grain it reduces the time to identification to only a few hours. With hand-held qPCRs this can also be performed in the field.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 42360550 · DOI · PMC13676668
Q4ddPCR: a flexible, 4-target assay for high-resolution HIV reservoir profiling [3]
Abstract reading summary — source excerpts
- Opening excerpt
- Precise and scalable quantification of the intact HIV reservoir is critical for advancing curative strategies.
- Closing excerpt
- Collectively, our findings confirm key predictions from mathematical modeling, demonstrating that multi-target assays improve specificity and more accurately capture intact reservoir dynamics.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (200 words)
Precise and scalable quantification of the intact HIV reservoir is critical for advancing curative strategies. Current reservoir assays, such as the intact proviral DNA assay (IPDA), are limited by quantification failures or misclassification of defective proviruses due to HIV sequence heterogeneity. Q4ddPCR is a modular, droplet digital PCR simultaneously targeting four conserved regions in the HIV genome to improve specificity, reduce quantification gaps, and provide multi-layered readouts. It comprises two configurations: one fully based on Q4PCR primer/probes and one combining IPDA with gag and pol primer/probes from Q4PCR. We benchmark Q4ddPCR against 3650 near full-length proviral sequences from 13 virally suppressed people with HIV (PWH) generated by Q4PCR. Q4ddPCR closely matches sequence-confirmed reservoir measurements, and multi-probe readouts reveal clonal reservoir dynamics not detectable by IPDA. Q4ddPCR enables intact reservoir quantification in 95% of samples across four independent cohorts and in 16 PWH, strongly correlates with viral outgrowth. In longitudinal samples from 42 participants over the first 4.5 years on antiretroviral therapy (ART), Q4ddPCR reports lower proviral frequencies and a steeper decline in intact proviral DNA compared to IPDA. Collectively, our findings confirm key predictions from mathematical modeling, demonstrating that multi-target assays improve specificity and more accurately capture intact reservoir dynamics.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41720775 · DOI · PMC13035820
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article The Ultimate qPCR Experiment: Producing Publication Quality, Reproducible Data the First Time [4]
- Research article Overcoming the bottleneck to widespread testing: a rapid review of nucleic acid testing approaches for COVID-19 detection [5]
- Research article Data Normalization Strategies for MicroRNA Quantification [6]
- Research article Diagnostic Performance of CT and Reverse Transcriptase Polymerase Chain Reaction for Coronavirus Disease 2019: A Meta-Analysis [7]
- Research article Diagnostics for SARS-CoV-2 detection: A comprehensive review of the FDA-EUA COVID-19 testing landscape [8]
- Research article PCR diagnosis of invasive candidiasis: systematic review and meta-analysis [9]
References
- Schmitt A, Proksch S, Gutzweiler L, Roth S, Engler M, Müller CSL, et al.. Diagnostic concordance of dermatopathology and PCR in differentiating eczema from psoriasis. . 2026. PMID 41814865 · DOI · PMC13308667
- Bakhiet S, Siddig E, Minlekib CP, Mohammed R, Zandijk W, Watson AK, et al.. A qPCR identification scheme to differentiate actinomycetoma from eumycetoma. . 2026. PMID 42360550 · DOI · PMC13676668
- Scheck R, Melzer M, Gladkov G, Leyre L, Ward AR, Reeves DB, et al.. Q4ddPCR: a flexible, 4-target assay for high-resolution HIV reservoir profiling. . 2026. PMID 41720775 · DOI · PMC13035820
- Taylor SC, Nadeau K, Abbasi M, Lachance C, Nguyen M, Fenrich J. The Ultimate qPCR Experiment: Producing Publication Quality, Reproducible Data the First Time. Trends Biotechnol. 2019. PMID 30654913 · DOI
- Esbin MN, Whitney ON, Chong S, Maurer A, Darzacq X, Tjian R. Overcoming the bottleneck to widespread testing: a rapid review of nucleic acid testing approaches for COVID-19 detection. RNA. 2020. PMID 32358057 · DOI · PMC7297120
- Schwarzenbach H, da Silva AM, Calin G, Calin G, Pantel K. Data Normalization Strategies for MicroRNA Quantification. Clin Chem. 2015. PMID 26408530 · DOI · PMC4890630
- Kim H, Hong H, Yoon SH. Diagnostic Performance of CT and Reverse Transcriptase Polymerase Chain Reaction for Coronavirus Disease 2019: A Meta-Analysis. Radiology. 2020. PMID 32301646 · DOI · PMC7233409
- Ravi N, Cortade DL, Ng E, Wang SX. Diagnostics for SARS-CoV-2 detection: A comprehensive review of the FDA-EUA COVID-19 testing landscape. Biosens Bioelectron. 2020. PMID 32729549 · DOI · PMC7368663
- Avni T, Leibovici L, Paul M. PCR diagnosis of invasive candidiasis: systematic review and meta-analysis. J Clin Microbiol. 2011. PMID 21106797 · DOI · PMC3043518
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-29.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.