When copying the HTT gene, DNA polymerase can basically lose track of which CAG it's on and accidently add extra CAGs.

当HTT基因复制时，DNA聚合酶基本上无法识别校对CAG列，意外地CAG列重复。

And they combed through those samples using software that recognized viral DNA sequences.

他们通过软件识别病毒DNA列来筛选这些样本。

The method allowed scientists to isolate and identify variable elements within a DNA sequence.

该方法允许科学并识别DNA列中的可变元素。

They were thought to do so aimlessly, but in 2017 it was discovered that some contained gene editing systems that were very good at recognizing specific DNA sequences.

人们认为它们这样做是毫无目的的，但2017年发现其中一些含有非常擅长识别特定DNA列的基因编辑系统。