+11 or trisomy 11 (solely) KMT2A

1997-07-01   François Desangles 

Clinics and Pathology

Disease

myeloid lineage: (AML, MDS)

Phenotype stem cell origin

M1, M2, and M4 AML;
therapy related AML;
MDS evolving towards AML;
stem cell immunophenotype (DR+, CD34+, and CD15, 33 and/or 13 positive);
trilineage dysplasia may be present;
to be noted that M1 and M2 subtypes of AML have rarely been found associated with the classical MLL rearrangements

Epidemiology

frequency: 1% of AML and MDS as well; balanced sex ratio; found in adults; med age: 60 yrs

Prognosis

short CR; poor prognosis

Cytogenetics

Cytogenetics morphological

+11

Cytogenetics molecular

partial(!) tandem duplication (in situ) of MLL, gene located in 11q23

Additional anomalies

none (by that very fact)

Genes Involved and Proteins

Gene name
KMT2A (myeloid/lymphoid or mixed lineage leukemia)
Location
11q23.3
Dna rna description
21 exons, spanning over 100 kb; 13-15 kb mRNA
Protein description
431 kDa; contains two DNA binding motifs (a AT hook, and Zinc fingers), a DNA methyl transferase motif, a bromodomain ;
wide expression;
nuclear localisation;
transcriptional regulatory factor

Result of the Chromosomal Anomaly

Description

exons 1 to 6 or 8 fused to a nearly entire MLL gene, starting at exon 2 (i.e. the duplicated segment is E2 to E6 or 8)AT hook and DNA methyltransferase from MLL in N-term fused to a quite entire MLL in C-term nuclear localisation probable altered transcriptional regulation

Bibliography

Pubmed IDLast YearTitleAuthors
26745631989Characteristics of trisomy 11 in childhood acute leukemia with review of the literature.Ingram L et al
78373911995Self-fusion of the ALL1 gene. A new genetic mechanism for acute leukemia.Schichman SA et al

Citation

François Desangles

+11 or trisomy 11 (solely) KMT2A

Atlas Genet Cytogenet Oncol Haematol. 1997-07-01

Online version: http://atlasgeneticsoncology.org/haematological/1026/+11-or-trisomy-11-(solely)-kmt2a