What genetic abnormality is associated with Chronic Myelogenous Leukemia (CML)?

Chronic Myelogenous Leukemia (CML) is closely associated with the genetic abnormality known as the Philadelphia chromosome, which is a specific translocation involving chromosomes 9 and 22. This translocation, denoted as t(9;22), results in the fusion of the BCR gene on chromosome 22 with the ABL gene on chromosome 9, creating a new fusion gene called BCR-ABL. This abnormal protein has tyrosine kinase activity that promotes uncontrolled cell proliferation and resistance to apoptosis, characteristic of the pathophysiology of CML.

The presence of the BCR-ABL fusion gene is a hallmark diagnostic feature of CML and plays a critical role in both the development and progression of the disease. The target of specific therapies, such as imatinib, is this fusion protein, as inhibiting its activity can lead to significant clinical responses in patients with CML.

In contrast, the other genetic abnormalities listed in the choices correspond to different hematologic malignancies. For instance, t(11;14) is associated with mantle cell lymphoma through the CCND1 gene, t(15;17) is linked to acute promyelocytic leukemia (APL) involving the PML-RARA fusion,