Evidence map›Paper›PMID 28166719›Full record

ArticleBMC bioinformatics2017

Not all predicted CRISPR-Cas systems are equal: isolated cas genes and classes of CRISPR like elements.

Quan Zhang, Yuzhen Ye

Open access · goldAbstract read
In one paragraph

Article in BMC bioinformatics, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 106 papers.

0numbers the graph read from it
0cells of the map it votes in
106citing papers in PubMed
10.2field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

106 citing papers in PubMed, 199 citations in OpenAlex.

  1. Article
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  7. Microorganisms · 2025
    Article
  8. Review
  9. Review
  10. Article
  11. Article
  12. Evolutionary trends inmSystems · 2025
    Article
  13. Article
  14. CRISPR-Cas9 and Its Bioinformatics Tools: A Systematic Review.Current issues in molecular biology · 2025
    Review
  15. Article
  16. Article
  17. Review
  18. Article
  19. Article
  20. Article

46 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors at 1 institution in 1 country.

Quan ZhangSchool of Informatics and Computing, Indiana University, 150 S. Woodlawn Ave, Bloomington, IN, 47405, USA.
Yuzhen YeSchool of Informatics and Computing, Indiana University, 150 S. Woodlawn Ave, Bloomington, IN, 47405, USA. yye@indiana.edu.ORCID http://orcid.org/0000-0003-3707-3185
Indiana University Bloomington · US

Funding

Graph-centric approaches to metatranscriptomic and metaproteomic data analysisR01AI108888 · NIAID · TRUSTEES OF INDIANA UNIVERSITY · PI YE, YUZHEN · 2014 to 2017
$1.4M
NIAID NIH HHS R01 AI108888
6 · The paper itself

Abstract

backgroundThe CRISPR-Cas systems in prokaryotes are RNA-guided immune systems that target and deactivate foreign nucleic acids. A typical CRISPR-Cas system consists of a CRISPR array of repeat and spacer units, and a locus of cas genes. The CRISPR and the cas locus are often located next to each other in the genomes. However, there is no quantitative estimate of the co-location. In addition, ad-hoc studies have shown that some non-CRISPR genomic elements contain repeat-spacer-like structures and are mistaken as CRISPRs.

resultsUsing available genome sequences, we observed that a significant number of genomes have isolated cas loci and/or CRISPRs. We found that 11%, 22% and 28% of the type I, II and III cas loci are isolated (without CRISPRs in the same genomes at all or with CRISPRs distant in the genomes), respectively. We identified a large number of genomic elements that superficially reassemble CRISPRs but don't contain diverse spacers and have no companion cas genes. We called these elements false-CRISPRs and further classified them into groups, including tandem repeats and Staphylococcus aureus repeat (STAR)-like elements.

conclusionThis is the first systematic study to collect and characterize false-CRISPR elements. We demonstrated that false-CRISPRs could be used to reduce the false annotation of CRISPRs, therefore showing them to be useful for improving the annotation of CRISPR-Cas systems.

Indexed as

CRISPR-Cas SystemsEnhancer Elements, GeneticGenome, BacterialClustered Regularly Interspaced Short Palindromic RepeatsGenetic LociGenomicsMolecular Sequence AnnotationPhylogenySoftwareStaphylococcus aureusStreptococcus pyogenesStreptococcus thermophilusCRISPR–Cas systemfalse-CRISPRSTAR-like elementTandem repeat

Identifiers

PMID28166719
PMCPMC5294841
OpenAlexW2587588342

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.