all libraries (Fig. 6b), implying that these enhancers are redundant in terms of transcription patterns but additive in terms of expression strength. Expression redundancy is also common in genomic clusters of closely spaced enhancers (24% of 815 identified genomic clusters, Supplementary Table 15). These are associated with TSSs of genes involved in immune and defense responses and, as suggested by a previous study27, have a higher expression than other enhancer-associated genes (8-fold increase on average).
