| Written | 2003-12 | Anne RM von Bergh, H Berna Beverloo |
| Afdeling Klinische Genetica, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands |
| Identity |
| Alias (NCBI) | HLXB9 (homeo box HB9) | HB9 | HOXHB9 | SCRA1 | Mnr1 |
| HGNC (Hugo) | MNX1 |
| HGNC Alias symb | HB9 | HOXHB9 | SCRA1 |
| HGNC Previous name | HLXB9 |
| HGNC Previous name | homeo box HB9 | homeobox HB9 |
| LocusID (NCBI) | 3110 |
| Atlas_Id | 393 |
| Location | 7q36.3 [Link to chromosome band 7q36] |
| Location_base_pair | Starts at 157004854 and ends at 157010663 bp from pter ( according to GRCh38/hg38-Dec_2013) [Mapping MNX1.png] |
| Fusion genes (updated 2017) | Data from Atlas, Mitelman, Cosmic Fusion, Fusion Cancer, TCGA fusion databases with official HUGO symbols (see references in chromosomal bands) |
| ETV6 (12p13.2) / MNX1 (7q36.3) | MNX1 (7q36.3) / ETV6 (12p13.2) | MNX1 (7q36.3) / MYB (6q23.3) | |
| MNX1 (7q36.3) / TRPM3 (9q21.12) | MYB (6q23.3) / MNX1 (7q36.3) |
| Note | telomeric to c7orf3 and SHH |
| DNA/RNA |
| Description | 3 exons stretched over an area of 5-6 kb. |
| Transcription | In a telomere to centromere direction; 2061 bp mRNA, 1206 bp open reading frame. |
| Protein |
| Description | The homeobox gene HLXB9 encodes the nuclear protein HB9. The protein contains a polyalanine repeat region and a homeobox domain. |
| Expression | Expressed in lymphoid and pancreatic tissues. Highly expressed in CD34+ bone marrow cells, down regulated upon differentiation. |
| Localisation | Nuclear |
| Function | Putative transcription factor. |
| Homology | Related to Mnr2. |
| Mutations |
| Note | Mutations in HLXB9 cause an autosomal dominant form of sacral agenesis, known as Currarino syndrome. |
| Implicated in |
| Note | |
| Entity | t(7;12)(q36;p13) - associated infant acute myeloid leukemia (AML) |
| Prognosis | Prognosis probably poor: median survival is 13 months. |
| Cytogenetics | t(7;12)(q36;p13), but not always visible by chromosome banding; may also be misdiagnosed as del(12)(p13). |
| Hybrid/Mutated Gene | 5' HLXB9 _ 3' ETV6 |
 | |
| Fig. 3. Schematic representation of the HLXB9 and ETV6 proteins and the putative HLXB9-ETV6 chimeric protein resulting from the t(7;12)(q36;p13). Arrow, the observed breakpoints. nt numbers (cDNA level) are given above each protein, and amino acid numbers are given in bold type below each protein. | |
| Abnormal Protein | N-term HLXB9, including its polyalanine repeat, is fused to a large C-term part of the ETV6 protein including its HLH domain and ETS domain; the homeobox domain of HLXB9 is not retained in the fusion protein; the reciprocal transcript is not expressed. |
| To be noted |
| The t(7;12) is heterogeneous at the molecular level. The formation of a fusion gene has only been described in 2 cases and may not be the only mechanism by which HLXB9 is involved in t(7;12)-associated leukaemias. Additional 7q36 genes may also be involved. |
| Bibliography |
| Fusion of the homeobox gene HLXB9 and the ETV6 gene in infant acute myeloid leukemias with the t(7;12)(q36;p13). |
| Beverloo HB, Panagopoulos I, Isaksson M, van Wering E, van Drunen E, de Klein A, Johansson B, Slater R |
| Cancer research. 2001 ; 61 (14) : 5374-5377. |
| PMID 11454678 |
| A novel human homeobox gene distantly related to proboscipedia is expressed in lymphoid and pancreatic tissues. |
| Harrison KA, Druey KM, Deguchi Y, Tuscano JM, Kehrl JH |
| The Journal of biological chemistry. 1994 ; 269 (31) : 19968-19975. |
| PMID 7914194 |
| A homeobox gene, HLXB9, is the major locus for dominantly inherited sacral agenesis. |
| Ross AJ, Ruiz-Perez V, Wang Y, Hagan DM, Scherer S, Lynch SA, Lindsay S, Custard E, Belloni E, Wilson DI, Wadey R, Goodman F, Orstavik KH, Monclair T, Robson S, Reardon W, Burn J, Scambler P, Strachan T |
| Nature genetics. 1998 ; 20 (4) : 358-361. |
| PMID 9843207 |
| Citation |
| This paper should be referenced as such : |
| von Bergh, ARM ; Beverloo, HB |
| HLXB9 (homeo box HB9) |
| Atlas Genet Cytogenet Oncol Haematol. 2004;8(1):12-13. |
| Free journal version : [ pdf ] [ DOI ] |
| Other Leukemias implicated (Data extracted from papers in the Atlas) [ 3 ] |
|
t(7;12)(q36;p13) MNX1/ETV6
t(7;12)(q34;p13) TRB/CCND2::t(12;14)(p13;q11) TRA or TRD/CCND2 t(6;7)(q23;q36) MYB/MNX1 |
| Other Cancer prone implicated (Data extracted from papers in the Atlas) [ 1 ] |
| Currarino syndrome |
| External links |
| REVIEW articles | automatic search in PubMed |
| Last year publications | automatic search in PubMed |
| © Atlas of Genetics and Cytogenetics in Oncology and Haematology | indexed on : Fri Jan 1 18:53:17 CET 2021 |
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