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Fig2. FISH analysis. FISH using BACs RPCI-11 461A8 (green) and RPCI-11 95J11 (red) showing that the signal of 95J11, which covers the initial part of the CREBBP gene, is split between der(10) and der(16). |
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| Additional anomalies | First described in a 4-year-old girl with AML M5a with 47,XX,der(7) t(7;10)(p13;p11),+8,der(10)t(7;10)(p13;p11)t(10;16)(q22;p13),der(16)t(10;16)(q22;p13)/46,XX. Later it was also described in an 84-year-old male without erythrophagocytosis and with this sole cytogenetic aberration. In addition, a variant breakpoint was described in a 52-year-old japanese woman with a therapy-related myelodysplastic syndrome (t-MDS) and also this sole translocation. Finally, another fusion variant was described in an AML-M4 female patient with the t(10;16) (q22;p13) and a t(11;17)(q23;q21). |
| Variants | There are no cytogenetic variants described, but there are molecular variants due to different breakpoints in the genes fused (see below). |
Fusion Protein| |  |
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Schematic representation of the fusion MYST4-CREBBP consequence of the t(10;16)(q22;p13). From up to down: MYST4 and CREBBP structures. H15 domain: domain in histone families 1 and 5; PHD zinc fingers: plant homeodomain (PHD) with a C4HC3-type motif, this domain is widely distributed in eukaryotes and it has been found in many chromatin regulatory factors; MOZ_SAS family region: this region has been suggested to be homologous to acetyltransferases but this similarity is not supported by sequence analysis; KIX domain: bind domain for CBP and P300, this domain also binds to transactivation domains of other nuclear factors including Myb and Jun. |
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| Description | In all cases published to date the breakpoints occur in the acidic domain of MYST4 but at different locations of the CREBBP protein: in the nuclear receptor-binding domain, in a C/H rich domain or between this domain and the KIX domain. The putative MYST4-CBP chimaeric protein retains the part of MYST4 that encodes the zinc fingers, two nuclear localization signals (NLS1 and NLS2), the HAT domain, and a portion of the acidic domain, and most of the CBP protein, including its HAT domain. |
| Oncogenesis | MYST4 has a 60% identity and 66% similarity to MYST3. All the fusions involving this genes result in several fusion proteins that target the acidic domain of MYST3 and MYST4. The partner fusion partners share also functional regions. All the fusion proteins are suspected to be leukaemogenic as a consequence of aberrant histone acetylation and transcription regulation, due probably but not exclusively, to the concomitant presence of two HAT domains coming from the different partners. |
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| Fusion of the MORF and CBP genes in acute myeloid leukemia with the t(10;16)(q22;p13). |
| Panagopoulos I, Fioretos T, Isaksson M, Samuelsson U, Billstrˆm R, Strˆmbeck B, Mitelman F, Johansson B |
| Human molecular genetics. 2001 ; 10 (4) : 395-404. |
| PMID 11157802 |
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| A novel fusion variant of the MORF and CBP genes detected in therapy-related myelodysplastic syndrome with t(10;16)(q22;p13). |
| Kojima K, Kaneda K, Yoshida C, Dansako H, Fujii N, Yano T, Shinagawa K, Yasukawa M, Fujita S, Tanimoto M |
| British journal of haematology. 2003 ; 120 (2) : 271-273. |
| PMID 12542485 |
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| t(10;16)(q22;p13) and MORF-CREBBP fusion is a recurrent event in acute myeloid leukemia. |
| Vizmanos JL, Larrˆ°yoz MJ, Lahortiga I, Floristˆ°n F, Alvarez C, Odero MD, Novo FJ, Calasanz MJ |
| Genes, chromosomes & cancer. 2003 ; 36 (4) : 402-405. |
| PMID 12619164 |
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| Variant MYST4-CBP gene fusion in a t(10;16) acute myeloid leukaemia. |
| Murati A, Adˆ©laˆØde J, Mozziconacci MJ, Popovici C, Carbuccia N, Letessier A, Birg F, Birnbaum D, Chaffanet M |
| British journal of haematology. 2004 ; 125 (5) : 601-604. |
| PMID 15147375 |
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