Atlas of Genetics and Cytogenetics in Oncology and Haematology
AF4 (ALL1 fused gene from chromosome 4)
AFF1 (AF4/FMR2 family, member 1)
| Identity |
| Other names | FEL |
| MLLT2 (myeloid/lymphoid leukemia translocated to, 2). | |
| HGNC | AFF1 |
| Location | 4q21 |
| Location_base_pair | Starts at 88147177 and ends at 88281215 bp from pter ( according to hg18-Mar_2006). |
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| MLLT2 (4q21) - Courtesy Mariano Rocchi, Resources for Molecular Cytogenetics. Laboratories willing to validate the probes are welcome : contact rocchi@biologia.uniba.it | |
| DNA/RNA |
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| Gene structure of AF4, containing the exon/intron structure as well as the distances of all three first exons (1a is encoded by two exons; 1b and 1c) and their distances from each other (unpublished data). There is also a stop in intron 3 (as designated) and an alternative splice of exon 18 to the 3'-NTR, skipping exon 19 and 20. Therefore this protein comes in different flavors, as there are presumably three independent promotor, and one carboxy-terminal exon skipping. | |
| Transcription | alternate splicing in 5' -> 10.5 and 12 kb; coding sequences: 3.6 kb. In addition, there are three independent first exons 1a, 1b and 1c (yet unpublished). |
| Protein |
| Description | 1210 amino acids; 140 KDa; contains many serine and proline rich sequences, a nuclear targeting sequence and a concensus sequence for ATP/GTP binding |
| Expression | widely expressed |
| Localisation | nuclear |
| Function | transcription activator |
| Homology | LAF4, AF5 and FMR-2 |
| Implicated in |
| Entity | t(4;11)(q21;q23)/acute leukaemias. --> MLL -AF4 |
| Disease | typically CD19+ B-ALL, biphenotypic AL, at times ANLL (M4/M5); may be congenital; treatment related leukaemia (secondary to epipodophyllotoxins) |
| Prognosis | median survival < 1yr |
| Cytogenetics | additional chromosome anomalies are found in 1/4 of cases of which is the i(7q) |
| Hybrid/Mutated Gene | 5' MLL-3' AF4; 12kb |
| Abnormal Protein | 240 kDa protein with about 1400 aminoacids from NH2 MLL and 850 from COOH AF4 (variable breakpoints); the reciprocal may or may not be expressed |
| External links |
| Bibliography |
| A serine/proline-rich protein is fused to HRX in t(4;11) acute leukemias. |
| Morrissey J, Tkachuk DC, Milatovich A, Francke U, Link M, Cleary ML |
| Blood. 1993 ; 81 (5) : 1124-1131. |
| PMID 8443374 |
| The t(4;11) chromosome translocation of human acute leukemias fuses the ALL-1 gene, related to Drosophila trithorax, to the AF-4 gene. |
| Gu Y, Nakamura T, Alder H, Prasad R, Canaani O, Cimino G, Croce CM, Canaani E |
| Cell. 1992 ; 71 (4) : 701-708. |
| PMID 1423625 |
| Chromosome abnormalities in leukaemia: the 11q23 paradigm. |
| Young BD, Saha V |
| Cancer surveys. 1996 ; 28 : 225-245. |
| PMID 8977038 |
| Molecular basis of 11q23 rearrangements in hematopoietic malignant proliferations. |
| Bernard OA, Berger R |
| Genes, chromosomes & cancer. 1995 ; 13 (2) : 75-85. |
| PMID 7542910 |
| 11q23 rearrangements in acute leukemia. |
| Rubnitz JE, Behm FG, Downing JR |
| Leukemia : official journal of the Leukemia Society of America, Leukemia Research Fund, U.K. 1996 ; 10 (1) : 74-82. |
| PMID 8558942 |
| Exon/intron structure of the human AF-4 gene, a member of the AF-4/LAF-4/FMR-2 gene family coding for a nuclear protein with structural alterations in acute leukaemia. |
| Nilson I, Reichel M, Ennas MG, Greim R, Knrr C, Siegler G, Greil J, Fey GH, Marschalek R |
| British journal of haematology. 1997 ; 98 (1) : 157-169. |
| PMID 9233580 |
| REVIEW articles | automatic search in PubMed |
| Last year publications | automatic search in PubMed |
| Contributor(s) |
| Written | 12-1997 | Jean-Loup Huret |
| Updated | 12-2002 | Rolf Marschalek |
| Citation |
| This paper should be referenced as such : |
| Huret JL . AF4 (ALL1 fused gene from chromosome 4); AFF1 (AF4/FMR2 family, member 1). Atlas Genet Cytogenet Oncol Haematol. December 1997 . URL : http://AtlasGeneticsOncology.org/Genes/AF4.html |
| Marschalek R . AF4 (ALL1 fused gene from chromosome 4); AFF1 (AF4/FMR2 family, member 1). Atlas Genet Cytogenet Oncol Haematol. December 2002 . URL : http://AtlasGeneticsOncology.org/Genes/AF4.html |
| © Atlas of Genetics and Cytogenetics in Oncology and Haematology | indexed on : Sat Dec 6 17:53:31 2008 |
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