ATM and thymus lymphoma: Nevertheless, one must bear in mind that translocations require two DSBs, so that TOP2-mediated lesions can contribute to the oncogenic events by providing partners for rearrangements that also engage Tcr or Ig loci, being the co-occurrence of TOP2- and RAG-mediated DNA breaks, and their stabilization and misrepair upon ATM loss, and not RAG-induced breaks per se, what drives ATM-deficient thymic lymphoma predisposition.