Which genetic abnormality is associated with chronic myeloid leukemia (CML)?

The Philadelphia chromosome is specifically associated with chronic myeloid leukemia (CML). This genetic abnormality results from a translocation between chromosome 9 and chromosome 22, which creates a fusion gene known as BCR-ABL. The BCR-ABL protein produced as a result of this fusion has abnormal tyrosine kinase activity, leading to the uncontrolled proliferation of myeloid cells characteristic of CML.

This specific chromosomal alteration is a cornerstone of the diagnosis and understanding of the pathophysiology of CML, making it a critical marker for both diagnosis and treatment monitoring in affected individuals. Other potential genetic abnormalities listed do not pertain to CML specifically; for example, the translocation of chromosomes 8 and 14 is typically associated with Burkitt lymphoma, while mutations in the TP53 gene are linked to various cancers, and deletion of chromosome 7 is more often associated with myelodysplastic syndromes. Hence, the Philadelphia chromosome stands out as the definitive genetic marker in the context of chronic myeloid leukemia.