Figure 4.

The chromatin compaction of a gene desert control region does not significantly change during cellular differentiation. The y-axis indicates interaction frequency and the x-axis shows genomic distance between interacting fragments. The average log ratio of corresponding contacts in undifferentiated and differentiated cells from this dataset was used to normalize the HoxA 3C datasets shown in Figure 3a. Interaction frequencies represent the average of at least three PCRs and error bars represent the standard error of the mean.