ChIP analysis of sheared chromatin from 10? HeLa cells using GTX60812 Histone H2A.Z antibody - ChIP grade. A titration of the antibody consisting of 0.2, 0.5, 1 and 2 microg per ChIP experiment was analysed. IgG (1 microg/IP) was used as negative IP control. Quantitative PCR was performed with primers specific for the promoter of the active genes c-fos and EIF2S3, used as positive controls, and for the coding region of the inactive MB gene and the Sat2 satellite repeat, used as negative controls. This figure shows the recovery, expressed as a % of input (the relative amount of immunoprecipitated DNA compared to input DNA after qPCR analysis).