Recently, CRISPR-based techniques have significantly improved our ability to make desired
changes and regulations in various genomes. Among them, targeted base editing is one of the
most powerful techniques in making precise genomic editing. Base editing enabled the irreversible
conversion of a specific single DNA base, from C to T or and from A to G, in desired genomic
loci. This technique has important implications in the study of human genetic diseases, considering
that many of them resulted from point mutations. More importantly, the high efficiency of these
editing tools also provided great promise in clinical applications. In this review, we discuss the recent
progress and challenges of base editing tools.