Glycosylase-mediated base editors show undetectable off-targets in mouse embryos

Developing glycosylase-based base editors to expand the editing scope is highly desirable for bio-medical research and agricultural applications. However, the off-target effect of glycosylase-based base editors remain to be investigated. Here, we utilized the Genome-wide Off-target analysis by Two-cell embryo Injection (GOTI) method to evaluate the off-target effects of adenine and guanine transversion base editors (AYBE-V106W and gGBE), derived from engineered N-methylpurine DNA glycosylase protein (MPG). The analysis revealed that no significant off-target effects were induced by these two editors in mouse embryos.