Fig. 7

Positions of chromosome breaks within the SAR region in BA-treated TWO4 cells. The genomic map of AF9 SAR region from nucleotide positions 236,059–246,292 is illustrated above [EMBL:ENSG00000171843]. BamH I (B), Kpn I (K) and Nde I (N) restriction sites are shown. Green arrows represent the primers (R1, AF9 236,451 R and F1, AF9 245,385 F) used in the first round of nested IPCR while the blue arrows represent the primers (R2, AF9 236,211 R and F2, AF9 245,507 F) used in the second round of nested IPCR. Green box represents the previously reported patient BCR which is indicated as BCR1 [88]. Yellow box shows the experimentally determined MAR/SAR which is indicated as SAR1 [88]. Yellow arrows represent the potential MAR/SARs predicted in this study. Blue box represents the AF9 region (at coordinates 245,252–245,612) previously reported to translocate with the MLL gene resulting in the MLL-AF9 fusion gene identified in an ALL patient [GenBank:AM050804]. Black boxes represent repeat elements. Red and green vertical lines represent the presently detected breakpoints in TWO4 cells treated with BA at neutral and acidic pH, respectively. All the chromosome breaks were mapped within BCR1 in close proximity to SAR1. Five chromosome breaks (at coordinates 245,509, 245,577, 245,594, 245,596 and 245,612) fall within the AF9 region previously reported to be involved in t(9;11)(p22;q23) in the ALL patient. One of those breakpoints is identical with that previously identified in the ALL patient (at coordinate 245,612) [GenBank:AM050804]. Three chromosome breaks (at coordinates 245,637, 245,664 and 245,711) fall within a repeat ERE2_EH (at coordinates 245,627–245,728). Two chromosome breaks fall at the same nucleotide position (at coordinate 245,803)