Evidence map›Paper›PMID 28875174›Full record

ArticleScience advances2017

Improved base excision repair inhibition and bacteriophage Mu Gam protein yields C:G-to-T:A base editors with higher efficiency and product purity.

Alexis C Komor, Kevin T Zhao, Michael S Packer, Nicole M Gaudelli, Amanda L Waterbury, Luke W Koblan, Y Bill Kim, Ahmed H Badran, David R Liu

Open access · goldAbstract read
In one paragraph

Article in Science advances, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 483 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
483citing papers in PubMed, 1 pooled it
29.9field-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

483 citing papers in PubMed, 1 synthesis or guideline pooled it, 767 citations in OpenAlex.

  1. CRISPR for cystic fibrosis: Advances and insights from a systematic review.Molecular therapy : the journal of the American Society of Gene Therapy · 2025
    Pooled it
  2. Base Editing: Mechanisms and Therapeutic Applications.Methods in molecular biology (Clifton, N.J.) · 2027
    Review
  3. Review
  4. Article
  5. Engineered Transformer Base Editor with Enhanced Editing Efficiency.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2026
    Article
  6. Review
  7. In vivo base editing of Asgr1 reduces blood lipids in mice.Molecular therapy : the journal of the American Society of Gene Therapy · 2026
    Article
  8. Article
  9. Article
  10. Article
  11. Article
  12. Review
  13. Article
  14. Review
  15. Article
  16. Article
  17. Article
  18. Review
  19. Review
  20. Review

423 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

9 authors at 2 institutions in 1 country.

Alexis C KomorDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.ORCID 0000-0001-5043-0998
Kevin T ZhaoDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Michael S PackerDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.ORCID 0000-0002-7842-997X
Nicole M GaudelliDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.ORCID 0000-0001-8608-4855
Amanda L WaterburyDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Luke W KoblanDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Y Bill KimDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Ahmed H BadranDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
David R LiuDepartment of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.ORCID 0000-0002-9943-7557
Broad Institute · USHarvard University · US

Funding

MOLECULAR BIOPHYSICS TRAINING GRANTT32GM008313 · NIGMS · HARVARD UNIVERSITY (MEDICAL SCHOOL) · PI MURTHY, VENKATESH N · 1989 to 2023
$14.6M
Integrating Chemistry and Evolution to Illuminate Biology and Enable Novel TherapeuticsR35GM118062 · NIGMS · HARVARD UNIVERSITY · PI LIU, DAVID R · 2016 to 2025
$6.4M
Principles of Scientific Citizenship: Ethics, Communication, and Leadership for ScientistsT32GM095450 · NIGMS · HARVARD UNIVERSITY · PI WALKER, SUZANNE · 2011 to 2020
$3.5M
Continuous Evolution of Proteins with Novel Therapeutic PotentialR01EB022376 · NIBIB · HARVARD UNIVERSITY · PI LIU, DAVID R · 2016 to 2019
$1.8M
Development and validation of a precision genome editing platformF32GM112366 · NIGMS · HARVARD UNIVERSITY · PI KOMOR, ALEXIS C. · 2015 to 2017
$122k
NIBIB NIH HHS R01 EB022376NIGMS NIH HHS F32 GM112366NIGMS NIH HHS R35 GM118062NIGMS NIH HHS T32 GM008313NIGMS NIH HHS T32 GM095450
6 · The paper itself

Abstract

We recently developed base editing, the programmable conversion of target C:G base pairs to T:A without inducing double-stranded DNA breaks (DSBs) or requiring homology-directed repair using engineered fusions of Cas9 variants and cytidine deaminases. Over the past year, the third-generation base editor (BE3) and related technologies have been successfully used by many researchers in a wide range of organisms. The product distribution of base editing-the frequency with which the target C:G is converted to mixtures of undesired by-products, along with the desired T:A product-varies in a target site-dependent manner. We characterize determinants of base editing outcomes in human cells and establish that the formation of undesired products is dependent on uracil N-glycosylase (UNG) and is more likely to occur at target sites containing only a single C within the base editing activity window. We engineered CDA1-BE3 and AID-BE3, which use cytidine deaminase homologs that increase base editing efficiency for some sequences. On the basis of these observations, we engineered fourth-generation base editors (BE4 and SaBE4) that increase the efficiency of C:G to T:A base editing by approximately 50%, while halving the frequency of undesired by-products compared to BE3. Fusing BE3, BE4, SaBE3, or SaBE4 to Gam, a bacteriophage Mu protein that binds DSBs greatly reduces indel formation during base editing, in most cases to below 1.5%, and further improves product purity. BE4, SaBE4, BE4-Gam, and SaBE4-Gam represent the state of the art in C:G-to-T:A base editing, and we recommend their use in future efforts.

Indexed as

Base PairingDNA RepairBacteriophage muCell LineDNA-Binding ProteinsEnzyme ActivationGene FrequencyGene OrderHumansINDEL MutationUracil-DNA GlycosidaseViral ProteinsDNA-Binding Proteinsgam protein, ColiphageUracil-DNA GlycosidaseViral Proteins

Identifiers

PMID28875174
PMCPMC5576876
OpenAlexW2751474071

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC
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.