Cytogenetics of chronic myeloproliferative disorders and related myelodysplastic syndromes

The only myeloproliferative disorder associated with any specific chromosome anomaly is chronic myeloid leukemia, which is linked with t(9;22)(q34;q11.2) or a variant of this anomaly. An association exists for del(13)(q12q14) and myelofibrosis; t(5;12)(q33;p13) and eosinophilia; and del(20q11), +8, and +9 and polycythemia vera, but these anomalies can be seen in various hematologic malignancies. The most common chromosomal anomalies among myeloproliferative disorders in order of frequency are t(9;22)(q34;q11.2), -Y, +8, +9, -7, del(20)(q11q13), del(13)(q12q14), del(5)(q13q33), and del(12)(p12). New fluorescent-labeled DNA techniques are useful for myeloproliferative disorders to study inadequate bone marrow or blood specimens and to monitor disease status among patients with known chromosome anomalies, but they are not more sensitive than conventional chromosome studies.