Fig. 6. A functionally essential role of constitutive CTCF loop domains.

a Display of a constitutive domain at the SOX17 locus that is conserved across 13 out of 16 human cell types. Arcs represent the domains in different cell types. The constitutive boundaries are shown via the box. b The pie plot shows the proportion of constitutive domains and domains. Constitutive domains are present in >50% of samples, while domains are present in ≤50% of samples. c Evolutionary conservation of consensus CTCF motifs at constitutive domain boundaries, domain boundaries, and nonboundaries. Nonboundary CTCF motifs are those motifs not in any domain boundaries. The motif region is shown in the box and the motif sequence is displayed. The average conservation score across placental mammals across all boundary regions is shown. The shaded area indicates the standard error. Two-sided Wilcoxon test P-values tested in the motif regions are shown. Data are presented as mean values ± SE. d Evolutionary conservation of consensus CTCF motifs at single-gene, multi-gene, and zero-gene boundaries of constitutive domains and nonboundaries. Nonboundary CTCF motifs are the motifs not in any constitutive domain boundaries. See more descriptions in c. Data are presented as mean values ± SE. e The number of common variants per consensus CTCF motif site at constitutive domain boundaries, domain boundaries and nonboundaries. Common variants are genetic variants with an allele frequency larger than 1% in the 1000 genome project phase 3 data. f The number of rare variants per consensus CTCF motifs at constitutive domain boundaries, domain boundaries, and nonboundaries. Rare variants are genetic variants with allele frequency less than 1% in 1000 genome phase 3 data.