Extended Data Figure 9: Long-range cis and trans contacts between Greek Islands and the active OR gene.

a, HiC Contacts that span more than 80 Mb are observed between the Olfr16 locus and Greek Islands in Olfr16⁺ cells. b, Close examination of the contacts (dashed box from a) reveals that Greek Islands contact Olfr16⁺ only in Olfr16⁺ cells (top, black arrowhead). Extremely long-range contacts between Greek Islands (gray arrowheads), but not involving the Olfr16 locus, are observed also in Olfr17⁺ and Olfr1507⁺ cells (middle, bottom). c, Heatmap depicting interchromosomal contacts between Olfr16 (chromosome 1) and Greek Islands from different chromosomes in in situ HiC from Olfr16⁺, Olfr17⁺ and Olf1507⁺ cells. d, 3D projection of APA between the Olfr16 locus and trans Greek Islands in the three specific mOSN populations. e, Heatmaps for contacts between Olfr16, Olfr17, or Olfr1507 and trans Greek Islands reveals an accumulation of contacts centered around the active allele. f, APA for an OR vs trans Greek Islands shows the accumulation of contacts on the active allele at 10 Kb resolution. The poor mappability of the Olfr17 locus and the lower sequencing depth perturbs the expected focal peak. For the Olfr1507 locus, the presence of the Greek Island, H, 50 Kb from Olfr1507 results in HiC contacts spanning a broad area. g,h, Short, long, and trans contacts with Greek Islands across the OR gene clusters containing Olfr17 (g) and Olfr1507 (h) plotted as fraction of the total HiC contacts mapped to each position (5 Kb resolution). Top panel shows contact in cells in which Olfr17/Olfr1507 is active, and the bottom panel shows data from Olfr16+ cells in which Olfr17/Olfr1507 is silent.