Research progress in developing reporter systems for the enrichment of positive cells with targeted genome modification

Targeted genome editing technology plays an important role in studies of gene function, gene therapy and transgenic breeding. Moreover, the efficiency of targeted genome editing is increased dramatically with the application of recently developed artificial nucleases such as ZFNs, TALENs and CRISPR/Cas9. However, obtaining positive cells with targeted genome modification is restricted to some extent by nucleases expression plasmid transfection efficiency, nucleases expression and activity, and repair efficiency after genome editing. Thus, the enrichment and screening of positive cells with targeted genome modification remains a problem that need to be solved. Surrogate reporter systems could be used to reflect the efficiency of nucleases indirectly and enrich genetically modified positive cells effectively, which may increase the efficiency of the enrichment and screening of positive cells with targeted genome modification. In this review, we mainly summarized principles and applications of reporter systems based on NHEJ and SSA repair mechanisms, which may provide references for related studies in future.