Atlas of Genetics and Cytogenetics in Oncology and Haematology
t(11;17)(q23;q12-21) MLL/AF17
| Identity |
| Note | not to be confused with the t(11;17)(q23;q12-21) involving MLL and LASP1 or the t(11;17)(q23;q12-21) involving MLL and ACACA |
 | |
| t(11;17)(q23;q12) G-banding - Courtesy Cytogenetics Laboratory of the CCRI, Children's Cancer Research Institute, Vienna. | |
| Clinics and Pathology |
| Disease | Acute myeloid leukemia (AML) |
| Epidemiology | not sufficient cases to date |
| Cytogenetics |
| Note | so far three MLL fusion partners, namely LASP1, AF17 (alias MLLT6), and ACACA have been identified in 17q12-21; these translocations cannot be distinguished cytogenetically and the accurate detection of the specific fusion gene requires RT-PCR or refined FISH analysis |
| Cytogenetics Molecular | chromosomes (arrows). |
 | |
| FISH using a combination of the MLL-specific PACs 217a21 and 167k13 (green signals) and the AF17-specific BAC RP11-25H10 (red signals) results in two fusion signals on the der(11) and the der(17) | |
| Probes | AF17-specific probes: BACs RP11-25H10 and RP11-58E17 |
| Additional anomalies | +8 |
| Genes involved and Proteins |
| Gene Name | MLL |
| Location | 11q23 |
| Dna / Rna | 37 exons, spanning over 100 kb; transcription in a centromeric to telomeric direction; 13 -15 kb mRNA; coding sequence 11.9 kb |
| Protein | 431 kDa; contains two DNA binding motifs (an AT hook, and Zinc fingers), a DNA methyl transferase motif, and a bromodomain; transcriptional regulatory factor; nuclear localization |
| Gene Name | MLLT6 (alias AF17) |
| Location | 17q12 |
| Note | previously LASP1 and AF17 (alias MLLT6) were mapped to 17q21, but according to the most recent genome assembly built by the Genome Bioinformatics Group of the University of California Santa Cruz and recent FISH data both genes are localized in 17q12 and proximal to RARA |
| Dna / Rna | encompasses 19.97 kb of genomic DNA; 4914 bp mRNA; 20 exons, 3282 bp coding sequence |
| Protein | 1023 amino acids, 112 kDa; MLLT6 (alias AF17), MLLT10 (alias AF10), and BRPF1 (alias BR140) belong to a small evolutionary highly conserved family of putative nuclear transcription factors, which contain amino-terminal PHD fingers, a highly conserved octapeptide, and a classical leucine zipper dimerization motif; nuclear localization |
| Result of the chromosomal anomaly |
| Transcript | 5' MLL - 3' AF17 |
 | |
| Schematic representation of MLL, AF17 (alias MLLT6), and the putative MLL-AF17 fusion protein. MT, methyltransferase domain; Zn finger, Zinc finger domain; SET-domain; PHD, Zinc finger PHD-type; OM, octapeptide motif; LZ, leucine-zipper dimerization motif. | |
| Description | the AT-hook DNA-binding domain and the methyltransferase motif including the CXXC zinc-finger (Zn) domain of MLL are fused to the highly conserved octapeptide (OM) and the leucine-zipper (LZ) dimerization motif of AF17 (alias MLLT6). |
| To be noted |
| Additional cases are needed to delineate the epidemiology of this rare entity: you are welcome to submit a paper to our new Case Report section. |
| Bibliography |
| Leucine-zipper dimerization motif encoded by the AF17 gene fused to ALL-1 (MLL) in acute leukemia. |
| Prasad R, Leshkowitz D, Gu Y, Alder H, Nakamura T, Saito H, Huebner K, Berger R, Croce CM, Canaani E |
| Proceedings of the National Academy of Sciences of the United States of America. 1994 ; 91 (17) : 8107-8111. |
| PMID 8058765 |
| AML with 11q23/MLL abnormalities as defined by the WHO classification: incidence, partner chromosomes, FAB subtype, age distribution, and prognostic impact in an unselected series of 1897 cytogenetically analyzed AML cases. |
| Schoch C, Schnittger S, Klaus M, Kern W, Hiddemann W, Haferlach T |
| Blood. 2003 ; 102 (7) : 2395-2402. |
| PMID 12805060 |
| A diagnostic biochip for the comprehensive analysis of MLL translocations in acute leukemia. |
| Maroc N, Morel A, Beillard E, De La Chapelle AL, Fund X, Mozziconacci MJ, Dupont M, Cayuela JM, Gabert J, Koki A, Fert V, Hermitte F |
| Leukemia : official journal of the Leukemia Society of America, Leukemia Research Fund, U.K. 2004 ; 18 (9) : 1522-1530. |
| PMID 15322560 |
| Acute myelocytic leukemia with t(11;17)(q23;q12-q21) involves a fusion of MLL and AF17. |
| Moore SD, Strehl S, Dal Cin P |
| Cancer genetics and cytogenetics. 2005 ; 157 (1) : 87-89. |
| PMID 15676155 |
| Contributor(s) |
| Written | 08-2005 | Sabine Strehl |
| Citation |
| This paper should be referenced as such : |
| Strehl S . t(11;17)(q23;q12-21) MLL/AF17. Atlas Genet Cytogenet Oncol Haematol. August 2005 . URL : http://AtlasGeneticsOncology.org/Anomalies/t1117q23q12AF17ID1027.html |
| © Atlas of Genetics and Cytogenetics in Oncology and Haematology | indexed on : Mon May 12 18:13:01 2008 |
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