Distribution of relative ratios of chromosome interaction changes. Upper panel: Histogram of relative ratios (chromosomal interaction changes in 1 Mb resolution, E2-treated vs control condition). Lower panel: sorted relative ratios, red smooth line is relative ratio equals 0.67 (e.g., a 2 fold change) and green smooth line is relative ratio equals 1.33 (e.g., a 5 fold change). Non-interaction elements are excluded from analysis such as Z-score equals 0 in both control and E2-treated interaction matrices. A 10-fold interaction change is expected when the relative ratio equals 1.63, gain and lost interactions are equivalent to the relative ratio 2 and −2, respectively.