The RAG2 C-terminus and ATM protect genome integrity by controlling antigen receptor gene cleavage

Mice lacking the C-terminal non-core domain of RAG2 and ATM mutant mice develop thymic lymphomas harbouring recurrent Tcra/d–Igh translocations. Here the authors show that ATM and the non-core domain of RAG2 prevent bi-locus recombination by modulating higher-order chromatin structure.