Abstract

The author describes atypical BCR/ABL fusion patterns among CML patients using FISH technique. The fusion BCR/ABL gene is usually observed at the der(22) chromosome while atypical rearrangements in CML patients are rare. As the relocation of BCR/ABL1 fusion sequence on sites other than 22q11 represents a rare type of variant Ph-translocation, the present study may highlight the hot spots involved in CML pathogenesis and assess their implications in Ph negative BCR/ABL1 positive CML. This study demonstrates the genetic heterogeneity of this subgroup of CML and the efficiency of FISH in detecting variations of the classical t(9;22). As atypical patterns may have clinical prognostic implications establishment of signal patterns may have important diagnostic implications.

Key words: Variant pH translocations, pH chromosome, BCR/ABL, FISH, chronic myeloid leukemia.