Author/Authors :
Bernasconi، نويسنده , , P. and Cavigliano، نويسنده , , P.M and Boni، نويسنده , , M and Malcovati، نويسنده , , L and Astori، نويسنده , , C and Castagnola، نويسنده , , C and Pagnucco، نويسنده , , G and Vanelli، نويسنده , , L and Calatroni، نويسنده , , S and Caresana، نويسنده , , M and Lazzarino، نويسنده , , M and Bernasconi، نويسنده , , C، نويسنده ,
Abstract :
We describe a 73-year-old man diagnosed with acute myelomonocytic leukemia (AML-M4) following myelodysplasia with trisomy 11 and with a t(11;11;22) . This is the first case with both abnormalities present in the same cells and with the t(11;11;22) involving a chromosome 11 already duplicated at 11q23. This band contains the MLL gene that undergoes partial tandem duplication in patients with +11, which is “promiscuous,” being translocated with a large number of genetic partners. Our patient had a complex karyotype that was completely defined by in situ hybridization. This technique demonstrated that the t(11;11;22) derivative with a duplication of band 11q23 carried from three to four copies of MLL. Two copies of the gene were close to each other and centromeric to the breakpoint region. Therefore, a partial tandem duplication of the MLL gene might have happened before the occurrence of t(11;11;22). Considering the associated chromosome defects, the monosomy for the long arm of chromosome 7, due to an unbalanced translocation t(7;17), further underlines the possibility that a partial tandem duplication of the MLL gene might have taken place.
