Altogether, these results suggest that a preferential usage of IGHV subgroups and genes by the expanded CLL/SLL clones from the Traf2DNxBCL2-tg+/+ mice is occurring, similar to what has been previously observed in human CLL patients and in the Eμ-TCL-1-tg mouse model of CLL. Here, TG is linked to B-cell chronic lymphocytic leukemia.