Different mechanisms lead to a karyotypically identical t(20;21) in myelodysplastic syndrome and in acute myelocytic leukemia.
A new t(20;21)(q11;q11), associated with a deletion on the long arm of chromosome 20, was found in one patient with an acute myelocytic leukemia (AML) and in one with myelodysplastic syndrome (MDS). In both cases deletion was interstitial, extending from band q11 to band q13, as shown by comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). FISH analysis with whole arm paints, subtelomeric probes, and locus-specific probes for the long arms of chromosomes 20 and 21 revealed in patient 1 a reciprocal translocation between the deleted 20q and the long arm of chromosome 21, that is, del(20)(q11q13)t(20;21)(q11;q11), and in patient 2, material from 21q was inserted into the deleted 20q, that is, del(20)(q11q13)ins(20;21)(q11;q11q22). This is the first identification of a complex 20;21 rearrangement in MDS/AML. Deletion at 20q and juxtaposition between 20q11 and 21q11 appear to be the critical genomic events.
Matteucci
Caterina
C
Ematologia, Università degli Studi di Perugia, 06123, Perugia, Italy. crimecux@unipg.it
La Starza
Roberta
R
Crescenzi
Barbara
B
Romoli
Silvia
S
Santoro
Alessandra
A
Magrin
Silvana
S
Lauria
Francesco
F
Coco
Francesco Lo
FL
Martelli
Massimo F
MF
Mecucci
Cristina
C
D000368:Aged; D000754:Anemia, Refractory, with Excess of Blasts / Q000235:genetics*; D002871:Chromosome Banding; D019457:Chromosome Breakage; D002872:Chromosome Deletion; D002890:Chromosomes, Human, Pair 20 / Q000235:genetics*; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics*; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization; D014178:Translocation, Genetic