Scientists get three higher-precision single-base editing tools for the first time

Yang Hui Research Group of the Center for Excellence and Innovation in Brain Science and Intelligent Technology of the Chinese Academy of Sciences (Neuroscience Research Institute), Guo Fan Research Group of Sichuan University and Li Yixuan Research Group of the Institute of Computational Biology under the Shanghai Institute of Nutrition and Health of the Chinese Academy of Sciences made their first discoveries through full transcription group RNA sequencing, including BE 3, BE3-hA3A and ABE7.10, including DNA editing tools single base editing technology there are a large number of RNA off-target, and ABE7.10 will also lead to a large number of cancer genes and anti-cancer gene mutations, with a strong risk of cancer. The researchers optimized the mutation of three single-base editing tools by point mutation, which completely eliminated the activity of RNA off-target, and obtained three more accurate single-base editing tools for the first time, providing an important basis for single-base editing technology to enter clinical treatment. The results were published online June 11 in the journal Nature.
single base editing is a high-precision gene editing technology, because it can achieve high-precision targeting, so it has become one of the most popular tools for gene therapy of rare diseases, for the treatment of genetic diseases caused by genetic mutations is of great significance.
, Yang Hui's team reported in Science that be3, a single base editing technique, was off-target across the genome, causing widespread concern. Previous studies have targeted off-target detection of gene editing tools at the DNA level, and this time Yang Hui's team extended the detection of DNA editing tools off-target to RNA levels, proving for the first time that a large number of RNA off-targeting techniques are commonly used in all three single-base editing techniques. Through a sophisticated experimental design, the researchers demonstrated that RNA off-targeting was mainly caused by deaminase fused on Cas9, and found that the highly-held ABE7.10 had a large number of RNA off-targeting and high-frequency cancer and anti-cancer genes.
To obtain more accurate single-base editing tools, the researchers mutated and optimized cytosine deaminase and adenine deaminase for single-base editing, respectively, resulting in a high-precision single-base editing tool that completely eliminates RNA off-targeting and maintains DNA editing activity. In addition, the ABE (F148A) mutants they developed were able to narrow the editing window for more accurate DNA editing.