第二部分大意：
堿基修正技術(shù)在去年被發(fā)現(xiàn)敌蜂。這種技術(shù)結(jié)合了CRISPR-Cas9以及一種叫作胞苷脫氨（基）酶的酶种冬，且該酶能夠連接在DNA上闹瞧。這種技術(shù)可以發(fā)現(xiàn)一個細(xì)胞中特定的G-C堿基對并轉(zhuǎn)換成T-A堿基對奢入。
在這周的自然雜志發(fā)表的論文中，另一項(xiàng)能夠把A-T堿基對轉(zhuǎn)換成G-C堿基對的堿基修正技術(shù)被發(fā)現(xiàn)般甲。這個技術(shù)比先前的那一項(xiàng)要難得多肋乍，因?yàn)檫@個技術(shù)中用到的酶在自然界中不存在，于是發(fā)明這項(xiàng)技術(shù)的小組的成員創(chuàng)造了它敷存。這項(xiàng)技術(shù)的成功率超過50%墓造，比單用CRISPR-Cas9的4%成功率高出不少堪伍，且不會對DNA產(chǎn)生不必要的新增或者刪減。
Base editing was invented last year. It combines CRISPR-Cas9 with a enzyme called cytidine deaminase, which can be bound to DNA and find specific G-C base pairs and convert them into T-A base pairs in a cell.
In one of the papers published by Nature this week, the extention of base editing technique which can convert A-T pairs into G-C ones was invented. It is harder than the one before because the enzyme it uses does not exist in nature, so the team who invented the technology set about creating it. It is proved to be effective more than half the time, which surpass the 4% when using CRISPR-Cas9 alone, and will not have unwanted insertion or deletion of DNA.
