You're not fishing through a whole chromosome in order to find what you want, but you're going to a cell that's already enriched in it.

你不是大海捞针地,在一整个染色体中找基因,而是在一个充满了,你感兴趣的基因的细胞里找

耶鲁公开课 - 生物医学工程探索课程节选

Plus,if you're looking for insulin, if you're looking for the gene for insulin you're going to cells that are making it already, they have abundant messenger RNA so it's much easier to separate out and identify the gene that you're interested in.

再者,如果你在找胰岛素,如果你在找胰岛素基因,你要到,正在制造胰岛素的细胞里找,里面有丰富的mRNA,所以更容易分离,并识别出你感兴趣的基因

耶鲁公开课 - 生物医学工程探索课程节选