~5-6 million dermal cells were fixed in 1% formaldehyde for 10 min at 37ºC. Crosslinked cells were lysed in lysis buffer (0.3% SDS, 50 mM Tris-HCl, pH=8.0, 20 mM EDTA, and freshly added protease inhibitors) on ice for 10 min, with vortexing every 2 min. Lysed samples were immediately subjected to 36 cycles of sonication at power 10 with a sonicator (Qsonica, Q700) to generate small chromatin fragments. 5 μg of the H3K27ac (ActiveMotif, 39133), and H3K27me3 (Millipore, 07-449), and CTCF (Thermal Fisher, PA5-17143), antibodies were used for immunoprecipitation. ChIP-seq libraries were prepared for sequencing using standard Illumina protocols