Screen results of FSC and H2B-mGFP screens. Cells (hTERT-RPE1 dCas9-KRAB-BFP PA-mCherry H2B-mGFP) were infected and puromycin selected for 3 d. The top 10th percentile of cells based on either GFP fluorescence or FSC signal were separately sorted and prepared for high-throughput sequencing. Screen results shown in volcano plot and their corresponding eFDR-η curve of two replicates as described in Fig. S3 b and Data S5.