Probe sets and images for the detection of deletions of the derivative chromosome 9.

(A) Structure of the ABL and BCR loci showing the common breakpoints (arrows) and the probes used in the dual-color, dual-fusion detection system. ASS indicates arginine succinate synthetase; Met8604, Met8604 gene; IGLV, immunoglobulin lambda light chain locus. (B) A representativeABL-BCR (1b-b4) rearrangement is shown on the derivative chromosome 9 with the position of the ABL1b,BCRb4, 1bAB, e16AB, and neste16 primers and the FISH fusion signal. (C) Fluorescence in situ hybridization (FISH) analysis of nondeleted and deleted Ph⁺ metaphase cells. In both cells, the normal chromosome 9 and 22 demonstrate a single red and green signal, respectively, with a fusion signal present on the Ph⁺ cell. In the nondeleted cell, the derivative chromosome 9 also demonstrates a fusion signal, but this is missing from the derivative chromosome 9 in the deleted cell.