Chronic myeloid leukemia (CML) is a clonal myeloproliferative expansion of primitive hematopoietic progenitor cells. Chronic myeloid leukemia (CML) is a clonal myeloproliferative (clone of multiplicating bone marrow cells) expansion of primitive hematopoietic progenitor cells involving myeloid, erythroid, megakaryocytic, B-lymphoid, and occasionally T-lymphoid lineages. CML was the first human disease in which specific abnormality of the karyotype the Philadelphia (Ph) chromosome could be linked to pathogenetic events of leukemia. The Ph chromosome is a shortened chromosome 22 resulting from a reciprocal translocation, t(9;22) (q34;q11). Chronic myelogenous leukemia (CML) is a hematopoietic stem cell cancer characterized by uncontrolled expansion of myeloid cells.1 In 90% to 95% of cases, CML is caused by a characteristic translocation between chromosomes 9 and 22. This translocation results in an abnormally short chromosome 22, the Philadelphia chromosome (Ph), and formation of the BCR-ABL1 fusion gene.1 The fusion gene in turn produces a constitutively active protein tyrosine kinase that causes CML.1 The remaining 5% to 10% of cases have a translocation involving 3 or 4 chromosomes or a cryptic translocation that cannot be detected by karyotyping.
Also known as: Chronic Myeloid Leukemia Karyotyping Bone Marrow.