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

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