title: Genome-wide translocation sequencing reveals mechanisms of chromosome breaks and rearrangements in B cells.
abstract: Whereas chromosomal translocations are common pathogenetic events in cancer, mechanisms that promote them are poorly understood. To elucidate translocation mechanisms in mammalian cells, we developed high-throughput, genome-wide translocation sequencing (HTGTS). We employed HTGTS to identify tens of thousands of independent translocation junctions involving fixed I-SceI meganuclease-generated DNA double-strand breaks (DSBs) within the c-myc oncogene or IgH locus of B lymphocytes induced for activation-induced cytidine deaminase (AID)-dependent IgH class switching. DSBs translocated widely across the genome but were preferentially targeted to transcribed chromosomal regions. Additionally, numerous AID-dependent and AID-independent hot spots were targeted, with the latter comprising mainly cryptic I-SceI targets. Comparison of translocation junctions with genome-wide nuclear run-ons revealed a marked association between transcription start sites and translocation targeting. The majority of translocation junctions were formed via end-joining with short microhomologies. Our findings have implications for diverse fields, including gene therapy and cancer genomics.
authors.affiliation: Howard Hughes Medical Institute, Immune Disease Institute, Program in Cellular and Molecular Medicine, Children's Hospital Boston and Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Roberto
authors.initials: R
authors.lastname: Chiarle
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Richard L
authors.initials: RL
authors.lastname: Frock
authors.forename: Susanna M
authors.initials: SM
authors.lastname: Lewis
authors.forename: Benoit
authors.initials: B
authors.lastname: Molinie
authors.forename: Yu-Jui
authors.initials: YJ
authors.lastname: Ho
authors.forename: Darienne R
authors.initials: DR
authors.lastname: Myers
authors.forename: Vivian W
authors.initials: VW
authors.lastname: Choi
authors.forename: Mara
authors.initials: M
authors.lastname: Compagno
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Malkin
authors.forename: Donna
authors.initials: D
authors.lastname: Neuberg
authors.forename: Stefano
authors.initials: S
authors.lastname: Monti
authors.forename: Cosmas C
authors.initials: CC
authors.lastname: Giallourakis
authors.forename: Monica
authors.initials: M
authors.lastname: Gostissa
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Alt
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism*; D002478:Cells, Cultured; D019457:Chromosome Breakage; D053903:DNA Breaks, Double-Stranded; D016259:Genes, myc; D016678:Genome; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D051379:Mice; D016296:Mutagenesis; D009369:Neoplasms / Q000235:genetics; D013154:Spleen / Q000166:cytology; D014178:Translocation, Genetic
chemical_list: D007143:Immunoglobulin Heavy Chains