Genomes across a wide range of eukaryotic organisms fold into higher-order chromatin domains. Topologically associating domains (TADs) were originally discovered empirically in low-resolution Hi-C heat maps representing ensemble average interaction frequencies from millions of cells. Here, we discuss recent advances in high-resolution Hi-C, single-cell imaging experiments, and functional genetic studies, which provide an increasingly complex view of the genome's hierarchical structure-function relationship. On the basis of these new findings, we update the definitions of distinct classes of chromatin domains according to emerging knowledge of their structural, mechanistic and functional properties.

中文翻译：

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关于拓扑关联域的存在和功能。

各种真核生物的基因组折叠成更高阶的染色质结构域。拓扑关联域 (TAD) 最初是在低分辨率 Hi-C 热图中凭经验发现的，代表来自数百万个细胞的整体平均交互频率。在这里，我们讨论了高分辨率 Hi-C、单细胞成像实验和功能遗传研究的最新进展，这些研究提供了对基因组层次结构-功能关系越来越复杂的看法。在这些新发现的基础上，我们根据对其结构、机制和功能特性的新知识更新了不同类别染色质域的定义。