A FISH comparison of variant derivatives of the recurrent dic(17;20) of myelodysplastic syndromes and acute myeloid leukemia: Obligatory retention of genes on 17p and 20q may explain the formation of dicentric chromosomes

Abstract

The dic(17;20) is a recurrent unbalanced translocation occurring rarely in myelodysplastic syndromes and acute myeloid leukemia. We have studied eleven cases with the dic(17;20) or a more complex derivative, all of which showed deletion of 17p and 20q material. The tumor suppressor gene TP53 was not always lost, supporting a more distal gene as the target of these 17p deletions. All derivatives could be interpreted as having initially been formed as a dicentric chromosome, those with a larger amount of material between the centromeres having undergone further rearrangement to stabilize the chromosome while retaining proximal 17p and proximal 20q material. We propose that critical sequences o..