ChIP assays were performed using HeLa cells, the Bioss antibody against H3K27me2 (cat. No. bs-53109R) and optimized PCR primer sets for qPCR. ChIP was performed with an Auto Histone ChIP-seq kit on the SX-8G IP-Star Compact automated system, using sheared chromatin from 1 million cells. A titration of the antibody consisting of 1, 2, 5, and 10 μg per ChIP experiment was analyzed. IgG (2 μg/IP) was used as negative IP control. QPCR was performed with primers for the promoter of the active GAPDH and EIF4A2 genes, used as negative controls, and for the promoter of the inactive HBB and the coding region of the inactive MYOD1 genes, used as positive controls. The figure shows the recovery, expressed as a % of input (the relative amount of immunoprecipitated DNA compared to input DNA after qPCR analysis). These results are in accordance with the observation that H3K27me2 is preferably present at silent genes.