Although base editors are useful tools for precise genome editing, current base editors can only convert either adenines or cytosines. We developed a dual adenine and cytosine base editor (A&C-BEmax) by fusing both deaminases with a Cas9 nickase to achieve C-to-T and A-to-G conversions at the same target site. Compared to single base editors, A&C-BEmax’s activity on adenines is slightly reduced, whereas activity on cytosines is higher and RNA off-target activity is substantially decreased.

中文翻译：

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双碱基编辑器催化人体细胞中的胞嘧啶和腺嘌呤碱基转换。

尽管碱基编辑器是精确基因组编辑的有用工具，但当前的碱基编辑器只能转换腺嘌呤或胞嘧啶。我们通过将两种脱氨酶与 Cas9 切口酶融合，开发了双腺嘌呤和胞嘧啶碱基编辑器 (A&C-BEmax)，以在同一靶位点实现 C 到 T 和 A 到 G 的转换。与单碱基编辑器相比，A&C-BEmax 对腺嘌呤的活性略有降低，而对胞嘧啶的活性较高，并且 RNA 脱靶活性大幅降低。