BTG1 and acute lymphoblastic leukemia: The REH cell line comes from a patient at ALL relapse, making it particularly notable that several deletions identified in the present study, affecting genes TBL1XR1 (146-k deletion on 3q26.32), NR3C1 (205-kb deletion on 5q31.3), and BTG1 (260-kb deletion on 12q21.33), have been shown to contribute to its GC drug resistance (van Galen et al, 2010; Jones et al, 2014; Xiao et al, 2019).