Sometimes subtle changes in the structure of a protein can convert it from an active state into an inactive state.

有时蛋白质结构上一些很小的变化,就能将其由激活态转变为非激活态

耶鲁公开课 - 生物医学工程探索课程节选

There might be these, what are called epigenetic differences that I mentioned changes in the structure around DNA, and those changes lead to differences in which fraction of the total genes in the chromosomes are being expressed by a particular cell.

可能存在的差异,叫做表观遗传差异,我之前说过的DNA结构上的变化,而这些变化导致,在特定细胞中,染色体组的全部基因中,只有一部分表达出来

耶鲁公开课 - 生物医学工程探索课程节选