ABL1 and BCR genes in chronic myeloid leukemia

A schematic representation of the ABL1 gene on chromosome 9 (A) and the BCR gene on chromosome 22 (B). All exons (red/blue boxes) have been scaled to the same size for clarity. Exon numbers are indicated above the coding sequence and the breakpoint cluster nomenclature is placed below the M-bcr (b1-b5). Introns are represented by the intervening lines. The various breakpoint regions are identified by double-headed arrows. The schematic fusion transcripts for the typical M-, m-, and µ-bcr are illustrated (C), while the translocation product is demonstrated on the right.