Cas Hybrid for Multiplexed Editing and Screening application (CHyMErA) is a new gene editing technique developed by scientists of University of Toronto and University of Minnesota, published in March 2020. This technique is able to target multiple sites on genome, which help the study of systematic mapping of genetic interactions (GIs) and interrogation of the functions of sizable genomic segments in mammalian cells. CHyMErA utilizes CRISPR-associated nucleases 9(Cas9) and 12a(Cas12a) along with the optimized guide RNAs, where Cas9 has high efficiency of editing, and Cas12a coordinates with various of guide RNAs, supported by the guide RNAs libraries generated by machine learning.
Comparing to previous CRISPR-based multitargeting strategies, CHyMErA is more efficient with respect to gene segment deletion, due to machine learning optimized gRNAs. The combination of Cas9 and Cas12a systems leverages twice the number of possible targeting sites in comparison to the use of either enzyme alone. In future, Cas9, Cas12a, and other Cas enzymes are expected to be engineered for expanding the multiplexed editing landscape of CHyMErA system.
Reference:
Gonatopoulos-Pournatzis, T., Aregger, M., Brown, K., Farhangmehr, S., Braunschweig, U., Ward, H., Ha, K., Weiss, A., Billmann, M., Durbic, T., Myers, C., Blencowe, B. and Moffat, J., 2020. Genetic interaction mapping and exon-resolution functional genomics with a hybrid Cas9–Cas12a platform. Nature Biotechnology, 38(5), pp.638-648.
