Fig. 4

TADs in large cliques interact with a large number of TADs also outside the clique. (A) Overlap between singleton TADs, binary-interacting TADs and TADs in cliques (of indicated size) with A and B compartment subtypes. (B) Concept of ‘degree’ of TAD interactions. A given TAD (purple node) can belong to a clique of, here, size 3 (containing two other TADs [white nodes]) and a clique of size 5 (red nodes); the latter is the ‘maximal clique size’ (see main text). The total number of interactions involving the purple TAD (i.e. the TAD ‘degree’) is 7 and is materialized by 7 edges. In this example, the ratio of (clique size / (degree + 1)) is 5/(7 + 1) = 0.625 (see panel C). (C) Ratios of (clique size / (degree + 1)) for TADs identified as singletons, binary interacting and in cliques. The graphs consistently show that the larger the clique size, the lower the ratio, i.e. the greater the number of inter-TAD interactions a TAD engages in outside the clique. Note that for singleton TADs, this ratio is (trivially) always 1