Premium
Molecular cytogenetics localizes two new breakpoints on 11q23.3 and 21q11.2 in myelodysplastic syndrome with t(11;21) translocation
Author(s) -
Wlodarska Iwona,
Selleri Licia,
La Starza Roberta,
Paternotte Caroline,
Evans Glen A.,
Boogaerts Marc,
Van den Berghe Herman,
Mecucci Cristina
Publication year - 1999
Publication title -
genes, chromosomes and cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.754
H-Index - 119
eISSN - 1098-2264
pISSN - 1045-2257
DOI - 10.1002/(sici)1098-2264(199903)24:3<199::aid-gcc4>3.0.co;2-v
Subject(s) - chromosomal translocation , biology , breakpoint , genetics , cosmid , gene duplication , locus (genetics) , cytogenetics , microbiology and biotechnology , chromosome , derivative chromosome , chromosome 17 (human) , karyotype , chromosome 22 , gene
Translocation t(11;21)(q24;q11.2) is a rare but recurrent chromosomal abnormality associated with myelodysplastic syndrome (MDS) that until now has not been characterized at the molecular level. We report here results of a molecular cytogenetic analysis of this translocation in a patient with refractory anemia. Using FISH with a panel of 11q and 21q cosmid/YAC probes, we localized the chromosome 11 breakpoint at q23.3 in a region flanked by CP‐921G9 and CP‐939H3 YACs, distal to the HRX/MLL locus frequently involved in acute leukemias. The chromosome 21 breakpoint was mapped in a 800‐kb fragment inserted into the CP‐145E3 YAC at 21q11.2, proximal to the AML1 gene. It is noteworthy that in all four cases with a t(11;21) reported until now, a second der(11)t(11;21) and loss of normal chromosome 11 could be observed either at diagnosis or during the course of the disease. Since in our case heteromorphism was detected by FISH on the centromeric region of the two der(11), the second der(11) chromosome could be the result of a mitotic recombination that had occurred on the long arm of chromosome 11, rather than of duplication of the original der(11). Constancy of secondary karyotypic changes resulting in an extra copy of the putative chimeric gene at der(11), loss of 11qter sequences, and partial trisomy 21 suggest that neoplastic progression of MDS cases with a t(11;21) may be driven by the same mechanism(s). Genes Chromosomes Cancer 24:199–206, 1999. © 1999 Wiley‐Liss, Inc.