In vivo base editing without DNA off-target mutations
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB40008 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| ERR4507160_1.fastq.gz | Fastqsanger.gz | |||
| ERR4507160_2.fastq.gz | Fastqsanger.gz | |||
| ERR4507170_1.fastq.gz | Fastqsanger.gz | |||
| ERR4507170_2.fastq.gz | Fastqsanger.gz | |||
| ERR4507180_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 369 |
Similar Datasets
Project description:RNA-programmable deaminases, known as base editors (BEs), enable precise single base conversions on genomic DNA and hold great promise for therapeutic application in patients. Recent studies, however, have raised serious concern with regard to off-target effects, questioning translatability of BEs to the clinic. Here we analyze transcriptome- and genome-wide off-target effects following AAV-mediated delivery of cytosine base editors (CBEs) in vivo in an unbiased manner. We show that low expression of CBEs allows sufficient on-target editing to cure a disease phenotype with no increase in off-target effects compared to untreated controls. To further improve safety of in vivo base editing, we developed a lipid nanoparticle (LNP)-mediated delivery system to transiently express BEs. We reach up to 21% on-target editing with no detectable transcriptome- or genome-wide off-target effects, and are able to reverse the disease phenotype of a phenylketonuria mouse model. These results have important implications, underlining the feasibility of transient in vivo base editing for therapeutic use in patients.
2020-08-24 | GSE148349 | GEO
Project description:Transient in vivo base editing with no detectable RNA- and DNA off-target mutations
| PRJNA623983 | ENA
Project description:CRISPR-Cas base editors are preferred tool for genome editing as they generate desired editing without any double strand break in the genome, as double stand break is detrimental to the cells. In our study we have demonstrated the significance of base editors in editing the highly homologous HBG promoter (HBG1 and HBG2) region to introduce novel HPFH-like mutation to elevate HbF for therapeutical applications. Previous studies revealed that the base editors can cause unintended Cas-independent edits at transcriptome level. To validate off-target at RNA level, we performed a transcriptome wide analysis. The frequency of unintended edits in the HUDEP-2 stable cell lines expressing the base editors with the gRNA were not significant compared to the control. We determined the ABE mediated A to I conversion and CBE mediated C to U conversion across the base edited samples. The RNA off-target analysis was carried out with the help of REDItools v 2 tool. This data suggests that despite high on-target editing in DNA, the Cas-independent RNA off-target were not at detectable range compared to control. The differential expression of 34 selected genes which necessitate globin regulation were compared between the unedited HUDEP WT, CBE control, ABE control, and edited ABE (with gRNA 2/11) and edited CBE (with gRNA 2/11). We observed that there is no significant differential gene expression between the edited and control cells except the gamma and delta globin genes. These results suggest that base editors are preferred tools to edit highly homologous HBG promoter region to created HPFH-like mutations inducing HbF levels without causing double strand breaks, larger deletions and no significant RNA off-targets which are detrimental to the gene edited cells.
2022-01-02 | GSE192801 | GEO
Project description:We examined the off-targets of new base editing tools at RNA level
2020-10-14 | GSE142840 | GEO
Project description:Base editors are RNA-programmable deaminases that enable precise single-base conversions in genomic DNA. However, off-target activity is a concern in the potential use of base editors to treat genetic diseases. Here, we report unbiased analyses of transcriptome-wide and genome-wide off-target modifications effected by cytidine base editors in the liver of mice with phenylketonuria. The intravenous delivery of intein-split cytidine base editors by dual adeno-associated viruses led to the repair of the disease-causing mutation without generating off-target mutations in the RNA and DNA of the hepatocytes. Moreover, the transient expression of a cytidine base editor mRNA and a relevant single-guide RNA intravenously delivered by lipid nanoparticles led to ~21% on-target editing and to the reversal of the disease phenotype; there were also no detectable transcriptome-wide and genome-wide off-target edits. Our findings support the feasibility of therapeutic cytidine base editing to treat genetic liver diseases.
| S-EPMC7610981 | biostudies-literature
Project description:We show that delivering the mitochondrial base editor DdCBEs via AAV transduction of somatic cells efficiently produces precise base editing of the intended region.
2022-01-19 | GSE184064 | GEO
Project description:CRISPR technology has demonstrated broad utility for controlling target gene expression. However, there remains a need for strategies capable of modulating expression via the precise editing of non-coding regulatory elements. Here we demonstrate that CRISPR base editors, a class of gene-modifying proteins capable of inducing single-base substitutions in DNA, can be harnessed to perturb target gene expression via the targeted mutagenesis of cis-acting sequences. Using the promoter region of the human huntingtin (HTT) gene as an initial target, we show that editing of the binding site for the transcription factor NF-κB led to a marked reduction in HTT gene expression. We find that these gene perturbations were persistent and specific, as a transcriptome-wide RNA-seq analysis revealed virtually no off-target effects. We further show that this base-editing platform could lower HTT in vivo, as its delivery to a mouse model of Huntington’s disease decreased HTT expression in striatal neurons, an outcome that we show also increased survival. Finally, we use this approach to target the amyloid-beta precursor protein, demonstrating that multiplexed editing of its promoter region could significantly perturb its expression, supporting the applicability of this method. These findings thus demonstrate the potential for base editors to regulate target gene expression.
2022-08-24 | GSE204833 | GEO
Project description:β-thalassemia is a highly prevalent monogenic recessive disease caused by mutations affecting the synthesis of the adult hemoglobin β-chains. Transplantation of autologous, genetically modified hematopoietic stem/progenitor cells (HSPCs) is an attractive therapeutic option. However, current gene therapy strategies based on the use of lentiviral vectors or CRISPR/Cas9 nuclease are not equally effective in all the patients and/or raise safety concerns. Base editing (BE), a new CRISPR/Cas9 derived genome editing tool, allows the effective introduction of point mutations at precise locations within the genome without generating double strand breaks. The two β0 mutations CD39 (CAG>TAG) and IVS2-1 (G>A) are among the most common and severe β-thalassemia mutations in the Mediterranean area and Middle East. We exploited the capacity of BE to correct these mutations in HSPCs from β-thalassemia patients. We demonstrated that red blood cells in vitro derived from edited HSPCs exhibited high β-globin levels and that the delayed erythroid differentiation typically observed in β-thalassemic cell cultures was corrected by our treatment. Finally, xenotransplantation experiments showed base editing in HSCs and correction of the β-thalassemic phenotype in vivo. Overall, our study provides in vitro and in vivo proof of efficacy of a BE approach to treat patients with prevalent and severe β-thalassemia mutations.
2025-05-05 | GSE273814 | GEO
Project description:Adenosine base editors (ABEs) facilitate the conversion of A•T base pairs to G•C base pairs, demonstrating significant potential for correcting pathogenic point mutations in humans. However, the off-target editing effects of ABEs remain inadequately characterized. In this study, we present a biochemical method, Selict-seq, designed to evaluate genome-wide off-target editing by ABEs. Selict-seq specifically captures dI-containing single-stranded DNA (ssDNA) and precisely identifies dA-to-dI mutation sites, thereby elucidating the off-target effects induced by ABEs. Through investigations involving three single-guide RNAs (sgRNAs), we identified numerous unexpected off-target edits both within and outside the protospacer regions. Analysis of these off-target sites revealed distinct characteristics of the ABE8e(V106W). These findings significantly advance our understanding of the off-target landscape associated with ABE8e. In summary, our approach enables an unbiased analysis of the ABE editome and provides a widely applicable tool for specificity evaluation of various emerging genome editing technologies.
2025-03-25 | GSE278492 | GEO