Cryptic 5' MLL gene insertion in an X-chromosome in acute myeloblastic leukemia.
Band 11q23 is known to be involved in translocations and insertions with a variety of partner chromosomes. They lead to MLL rearrangement, resulting in fusion with numerous genes. We report here on a 43-year-old man presenting with asthenia and pancytopenia who was diagnosed with acute myeloblastic leukemia FAB-M5. Conventional cytogenetic techniques showed a del(11)(q21). Using a specific probe for fluorescent in situ hybridization, the MLL gene was found to be disrupted, with the 5' region being inserted into the X-chromosome (around bands q24 approximately q25), as confirmed by whole X-chromosome painting. The accumulating data on acute myeloblastic leukemia demonstrate that the 5'-MLL insertion in an X-chromosome is a rare but recurrent abnormality associated with leukemia, not only in infants, but also in adults.
Douet-Guilbert
Nathalie
N
Service de Cytogénétique, Cytologie et Biologie de la Reproduction, CHU Morvan, Brest, France.
Arnaud
Bertrand
B
Morel
Frédéric
F
Le Bris
Marie-Josée
MJ
De Braekeleer
Marc
M
D000328:Adult; D002880:Chromosomes, Human, Pair 11; D041321:Chromosomes, Human, X; D004268:DNA-Binding Proteins / Q000235:genetics*; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000235:genetics*; D008297:Male; D051788:Myeloid-Lymphoid Leukemia Protein; D011519:Proto-Oncogenes / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014178:Translocation, Genetic
D004268:DNA-Binding Proteins; C497422:KMT2A protein, human; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase