Molecular Demonstration of BCR/ABL Fusion in a Patient with Chronic Myelogenous Leukemia with Basophilia Carrying a Variant t(16;22) (q24;q11) Philadelphia Chromosome

Abstract

We report a patient with chronic myelogenous leukemia in chronic phase and basophilia which was found to carry a simple variant t(16;22) (q24;qll) Philadelphia (Ph) chromosome in unstimulated bone marrow mononuclear cells. Molecular analysis of peripheral blood and bone marrow mononuclear cells demonstrated the presence of a bcr-abl chimeric mRNA transcript of the b₃-a₂ type. These findings confirm that band 9q34 participates in the formation of all Ph chromosomes, either standard or variant, even when this is not detectable by conventional cytogenetics. The available literature concerning variant Philadelphia translocations is also reviewed.

Keywords:

• Variant
• Ph chromosome
• CML
• basophilia