Schematic representation of the MM breakpoints location in the 11q13 region. For details, see Raynaud et al9(XG1,XG2,XG5 cell lines), Meeus et al15 (two MM cases), Chesi et al16 (SK-MM2 cell line), and Vaandrager et al33 (KMS-12 cell line). The arrows indicate cases for which the breakpoint has been cloned; the dashes indicate cases for which the breakpoint has been approximately mapped by FISH or Southern blot analyses.