Expression of NUP98/TOP1, but not of TOP1/NUP98, in a treatment-related myelodysplastic syndrome with t(10;20;11)(q24;q11;p15)..     ///    "Recently, the t(11;20) was shown to result in a fusion of the NUP98 and TOP1 genes, with expression of the NUP98/TOP1 chimera encoded by the der(11)t(11;20), but not of the reciprocal TOP1/NUP98 on the der(20)t(11;20). "    ///    Reverse transcriptase-polymerase chain reaction (RT-PCR) revealed a NUP98/TOP1 fusion in which exon 13 of NUP98 was fused in-frame with exon 8 of TOP1.     ///    "The present results provide further support for the involvement of the NUP98/TOP1 transcript, but not of the reciprocal one, in the development of MDS/AML. "    ///    "Genomic XL PCR did not amplify the reciprocal TOP1/NUP98, nor was this chimera expressed, as expected from the cytogenetic finding. "