Extended Data Figure 7: Strategy to generate chromosomal translocations in human B cells from DSBs introduced in the c-MYC locus by CRISPR/Cas9 technology.

a, Schematic representation of the experimental strategy employed to generate chromosomal translocation from the c-MYC locus by introducing DSBs in c-MYC intron 1 by two different sgRNAs (c-MYC-#1 or c-MYC-#2). Arrowheads (black) indicate the cleavage sites introduced by Cas9 and PAM sequence is in red. b, Surveyor Assay to measure the cutting efficiency of the c-MYC gene targeted in JeKo-1 cell line. Locus modification efficiencies are analysed 5 days after transduction of c-MYC-#1 or c-MYC-#2 Cas9 lentivirus. Estimated indel formation is indicated below each target. Black arrowheads indicate the size of the observed bands. N.D.:, not detectable. One representative experiment out of three performed with comparable results is shown. For gel source data, see Supplementary Fig. 1. c, Histograms showing frequency of translocation junctions in Cas9 off-target sites for c-MYC-#2 sgRNAs in MEC1 cell line treated with idelalisib or duvelisib. AID-knockout MEC1 cells were generated by CRISPR/Cas9-mediated deletion (Extended Data Fig. 8e). For each treatment, data are from pooled HTGTS libraries of similar size from independent experiments as indicated in Supplementary Table 1. d, Detailed view of the distribution of translocation junctions in representative Cas9 off-target site for c-MYC-#2. Numbers of translocation junctions in focal clusters are indicated in bold. e, f, Histograms showing translocation junctions frequency in Cas9 off-targets sites for c-MYC-#1 (e) or c-MYC-#2 (f) sgRNAs in JeKo-1 cell line treated with idelalisib or duvelisib. For each treatment, data are from pooled HTGTS libraries of similar size as indicated in Supplementary Table 1. g, h, Detailed view of the distribution of translocation junctions in representative Cas9 off-target sites for c-MYC-#1 (g) or c-MYC-#2 (h). Numbers of translocation junctions in focal clusters are indicated in bold.