The Ph¹ Chromosome and the BCR-ABL Fusion Gene

• Translocation of the BCR gene from chromosome 9 to the ABL gene on chromosome 22.
• The hybridized fusion, BCR-ABL gene produces an altered protein with tyrosine kinase activity.
• The net effective of the gene expression is to enhance cell division and reduce apoptosis.
• Thus triggering unregulated myeloproliferation.
• The image to the right is of two different sets of metaphase chromosomes. The fusion gene is identified with a yellow colored probe. If you don't see it, roll the cursor over the picture.