Base editing technology induces precise base substitutions to achieve genome editing through combining two moieties, "effector" and "locator".
CRISPR-mediated Gene Editing and Base Editing
More than 75,000 genetic mutations are corelated with human diseases and around half of these diseases are caused by point mutations, which are hard to be fixed by traditional gene editing tools. Base editing technology can realize single base pair change in human genome in a precise and permanent manner. Thus, base editing technology provides great potential for the cure of hereditary diseases and the immunotherapy of cancer.
Our Base Editing Systems
Our scientific founders have developed five series base editing systems, including enhanced Base Editor (eBE), dCpf1 Base Editor (dCpf1-BE), human APOBEC3A Base Editor (hA3A-BE), BEACON, transformer Base Editor (tBE).
transformer Base Editor (tBE) with Ultra-high Editing Precision
tBE was developed with ultra-high editing precision to eliminate both gRNA-dependent and gRNA-independent off-target mutations (tBE, Nature Cell Biology, 2021). Through a cleavable “lock”, tBE becomes active only at on-target sites to induce highly efficient editing. When binding at off-target sites, tBE was “locked” to avoid triggering off-target mutations. Like a “Transformer”, tBE has great flexibility to suit for different kinds of deliver methods such as AAV and mRNA/LNP. Furthermore, tBE can simultaneously edit multiple target sites with high efficiency. These characters greatly expand the scope of tBE’s clinical application.
▲ transformer Base Editor (tBE) of Correctseq
Base Editing Therapy
With traditional transgene therapy, the original mutations still exist, which makes it hard to be applied to treat the hereditary diseases caused by dominant-negative mutations. Also, the lifelong effect of transgene therapy is yet to be validated. Comparing with transgene therapy, base editing therapy which can be applied in vivo and ex vivo fixes the mutations directly and can cure various genetic diseases for a lifelong effect. Compared with Cas Nuclease gene editing therapy, tBE exhibits undetected off-target mutations, higher editing efficiency and better therapeutic effect, and lower cytotoxicity.
Reviews, Comments, Interviews
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