title: Trisomy 11 and a complex t(11;11;22) in a patient with acute myelomonocytic leukemia (AML-M4) following myelodysplasia (MDS): a cytogenetic study of a mechanism of leukemogenesis.
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 break-point 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.
authors.affiliation: Istituto di Ematologia, Università di Pavia, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Bernasconi
authors.forename: P M
authors.initials: PM
authors.lastname: Cavigliano
authors.forename: M
authors.initials: M
authors.lastname: Boni
authors.forename: L
authors.initials: L
authors.lastname: Malcovati
authors.forename: C
authors.initials: C
authors.lastname: Astori
authors.forename: C
authors.initials: C
authors.lastname: Castagnola
authors.forename: G
authors.initials: G
authors.lastname: Pagnucco
authors.forename: L
authors.initials: L
authors.lastname: Vanelli
authors.forename: S
authors.initials: S
authors.lastname: Calatroni
authors.forename: M
authors.initials: M
authors.lastname: Caresana
authors.forename: M
authors.initials: M
authors.lastname: Lazzarino
authors.forename: C
authors.initials: C
authors.lastname: Bernasconi
mesh_terms: D000368:Aged; D002880:Chromosomes, Human, Pair 11; D002892:Chromosomes, Human, Pair 22; D002895:Chromosomes, Human, Pair 5; D002897:Chromosomes, Human, Pair 7; D004268:DNA-Binding Proteins / Q000235:genetics; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D015479:Leukemia, Myelomonocytic, Acute / Q000235:genetics*; D008297:Male; D009006:Monosomy; D009190:Myelodysplastic Syndromes / Q000235:genetics*; D051788:Myeloid-Lymphoid Leukemia Protein; D011519:Proto-Oncogenes; D014157:Transcription Factors; D014178:Translocation, Genetic / Q000235:genetics*; D014314:Trisomy / Q000235:genetics*; D014998:Y Chromosome
chemical_list: D004268:DNA-Binding Proteins; C497422:KMT2A protein, human; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase