Enhancing prime editing efficiency and flexibility with tethered and split pegRNAs

Dear Editor,Most human genetic diseases arise from mutations such as insertion,deletion,or point mutations(Landrum et al.,2016).CRISPRCas system has been repurposed to correct pathogenic mutations in a variety of genetic diseases(Choi et al.,2022).There are many concerns about using CRISPR-mediated double-stranded DNA breaks(DSBs)for therapeutic purposes,primarily due to off-targeted mutations(Kosicki et al.,2018).Nevertheless,base editing cannot correct deletions,insertions,or some point mutations such as transversion mutations.Prime editing has its advantages of precisely correct point mutations,small insertions,or deletions in animal cells(Anzalone et al.,2019)and plants(Lin et al.,2020).However,prime editing efficiency varies among genomic sites or cell types(Chen et al.,2021;Nelson et al.,2022).