The Philadelphia (Ph) chromosome is the hallmark of chronic myelogenous leukemia (CML). It is a shortened chromosome 22 resulting from a reciprocal translocation, t(9;22)(q34;q11), between the long arms of chromosomes 9 and 22. It is found in up to 95% of patients.
However, 5–10% of patients with Ph-positive CML have variant translocations involving chromosomes other than 9 and 22.
In this article, nine CML cases are being reported that carry variant Ph translocations involving both chromosomes 9 and 22, as well as chromosomes 2, 3, 8, 14, 16, and other various chromosomes, resulting in either a simple or complex karyotype.
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