In our study, crossing Eμ-XPO1 mice with the Eμ-TCL1 mouse, which is the most common murine model of CLL, Eμ-XPO1xTCL1 mice expressing E571K- or E571G-XPO1 displayed a more rapid onset of their CLL-like disease. Here, XPO1 is linked to B-cell chronic lymphocytic leukemia.