Comparison of DNA targeting CRISPR editors in human cells

Background: Profiling and comparing the performance of current widely used DNA targeting CRISPR systems provide the basic information for the gene-editing toolkit and can be a useful resource for this field. Herein we made a parallel comparison between the recently reported miniature Cas12f1 and the widely used Cas12a and Cas9 nucleases in mammalian cells. Results: We found that as a CRISPRa activator, Un1 Cas12f1 could induce gene expression with a comparable level to these of Cas12a and Cas9, while as a cleaving editor, Cas12f1 exhibited similar properties to Cas12a, like high specificity and dominantly induced deletions over insertions, but with less activity. In contrast, wild type SpCas9 showed the highest activity, lowest specificity, and induced balanced deletions over insertions. Thus, Cas12 f1 is recommended for gene activation based applications, Cas12a is for therapy applications, and wild type Cas9 is for in vitro and animal investigations. Conclusion: The comparison provided the editing properties of current widely used DNA-targeting CRISPR systems for the gene-editing field.