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Cited by 15CRISPR and Genetic EngineeringRetinal Development and DisordersRNA regulation and disease

Comparison of CRISPR-Cas13b RNA base editing approaches for USH2A-associated inherited retinal degeneration

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Fry, Lewis E., Major, Lauren, Salman, Ahmed, McDermott, Lucy A., Yang, Jun, King, Andrew J., McClements, Michelle E., MacLaren, Robert E.·2025·Communications Biology
DOI 10.1038/s42003-025-07557-3PMC PMC11807095
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Abstract

CRISPR-Cas13 systems have therapeutic promise for the precise correction of point mutations in RNA. Using adenosine deaminase acting on RNA (ADAR) effectors, A-I base conversions can be targeted using guide RNAs (gRNAs). We compare the Cas13 effectors PspCas13b and Cas13bt3 for the repair of the gene USH2A , a common cause of inherited retinal disease and Usher syndrome. In cultured cells, we demonstrate up to 80% efficiency for the repair of the common c.11864 G > A and its murine equivalent c.11840 G > A, across different gRNAs and promoters. We develop and characterize a mouse model of Usher syndrome carrying the c.11840 G > A mutation designed for the evaluation of base editors for inherited retinal disease. Finally, we compare Cas13 effectors delivered via AAV for the repair of Ush2a in photoreceptors. Mean RNA editing rates in photoreceptors across different constructs ranged from 0.32% to 2.04%, with greater efficiency in those injected with PspCas13b compared to Cas13bt3 constructs. In mice injected with PspCas13b constructs, usherin protein was successfully restored and correctly localized to the connecting cilium following RNA editing. These results support the development of transcriptome targeting gene editing therapies for retinal disease.

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  • A recent study evaluating several Cas13 in murine photoreceptors reported a gene-editing success rate of 2.04%, accompanied by retinal thinning following AAV-mediated delivery.

    “A recent study evaluating several Cas13 in murine photoreceptors reported a gene-editing success rate of 2.04%, accompanied by retinal thinning following adeno-associated virus (AAV)-mediated delivery [9].”

    From Precise CRISPR/Cas9 and Cas12 Correction Using Lipoplexes in Retinal Models Derived from Patients with Inherited Retinal Dystrophies (2026) · cites this paper as [9]

    The Results (‘In vivo editing of Ush2a with AAV-delivered Cas13-ADAR’) report a 2.04% ± 0.16 editing rate for the RK-dPspCas13b vector in mouse retinas. The Results (‘Effect of AAV-delivered Cas13-ADAR on retinal structure’) also report greater photoreceptor-layer thinning after AAV injection than after buffer injection. The qualification is that the measured outcome was RNA editing, not genomic gene editing. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

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Cited by

Sorted by citations

Authors
Fry, L. E., Major, L., Salman, A., McDermott, L. A., Yang, J., King, A. J., McClements, M. E., & MacLaren, R. E.
Affiliations
  • University of Oxford (GB)
  • University of Utah (US)
Corresponding author
MacLaren, Robert E.
ORCID
Venue
Communications Biology
Publisher
Springer Science and Business Media LLC
Published
2025-02-08
Volume
8
Issue
1
Pages
200-200
ISSN
2399-3642 (ISSN-L)
DOI
10.1038/s42003-025-07557-3
PMC
PMC11807095
OpenAlex
W4407265809
Cited by
15
References
2
Citations by year
2026: 10 · 2025: 5
FWCI
4.51
Type
journal article
Language
en
Open access
Licence
Locations
  • Communications Biology (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Wellcome Trust ([WT108369/Z/2015/Z], WT108369)
  • National Institute for Health and Care Research
  • Royal College of Surgeons of Edinburgh
  • National Institutes of Health
  • Medical Research Council (MC_PC_19049)
  • NIHR Oxford Biomedical Research Centre
  • National Eye Institute (R01EY034524)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › CRISPR and Genetic Engineering
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Retinal Development and Disorders
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › RNA regulation and disease
Keywords
RNA base editing, USH2A, Usher syndrome, inherited retinal degeneration, ADAR, AAV gene delivery, photoreceptors, connecting cilium, mouse model
MeSH terms
Gene Editing, RNA, Guide, CRISPR-Cas Systems, Dependovirus, Adenosine Deaminase, Animals, Disease Models, Animal, Humans, Mice, Inbred C57BL, Retina, Retinal Degeneration, Extracellular Matrix Proteins, RNA-Binding Proteins, Point Mutation, RNA Editing, Mice, Knockout, Transgenes, Mice, Usher Syndromes, Targeted Gene Repair, CRISPR-Cas Systems

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