t(1;22)(p13;q13) RBM15/MKL1

2001-06-01   Jean-Loup Huret 

1.Genetics, Dept Medical Information, University of Poitiers, CHU Poitiers Hospital, F-86021 Poitiers France

Clinics and Pathology


only found so far in M7 AML (acute megakaryocytic leukaemia); not found in Down syndrome (DS), and yet, DS is a disease with highly elevated risk of M7 (see leukaemia and Down Syndrome); misdiagnoses of a solid tumour have been documented

Phenotype stem cell origin



no known toxic exposure


about 40 known cases; 0% to 3% of paediatric AML; 70 to 100% of infants M7; age: infants: median age 4 mths; 20% are < 1mth; 80% are < 1 yr; 95% are < 2 yrs; sex ratio: 15M/24F (non significant)


no preceeding myelodysplasia, and no history of transient leukemoid reaction; prominent organomegaly; blood data: moderate WBC; thrombocytopenia; myelofibrosis and fibrosis of other organs


platelet-specific markers: platelet-peroxidase by electron microscopy, or platelet glycoproteins IIb/IIIa (CD41) or IIIa (CD61)


bone marrow transplantation is indicated


complete remission in only 50% of cases; median survival: 8 months; a few long survivors; absence of a prognostic indicator


Additional anomalies

60% of cases (mostly patients under 6 mths of age) have the t(1;22) as a single anomaly; the remaining third of cases (mainly patients above the age of 6 mths) exhibit complex and hyperploid clones, with a highly monomorph pattern: +2, +19, +der(1)t(1;22), +6, +21 were found in more than 50% of cases each, +10, +7, +15, +18, +8, +20, del(1p), +4, +9, +14, +17, add(21p) are also recurrent; survival was equivalent in cases with or without a complex karyotype; the frequent presence of an additional der(1) indicates that the crucial event is likely to lie on the der(1)t(1;22)


2 cases of complex t(1;22) with a third chromosome have been described

Genes Involved and Proteins

Gene name
RBM15 (RNA binding motif protein 15)
Protein description
contains RNA recognition motif consensus
Gene name
MKL1 (megakaryoblastic leukemia (translocation) 1)
Protein description
931 amino acids; could attach DNA to nuclear scaffold and be involved in chromatin organization

Result of the Chromosomal Anomaly


5 OTT - 3 MAL, comprisng most of OTT fused to most of MAL; the reciprocal 5 MAL - 3 OTT may or may not be present


may modulate chromatin organization, HOX differentiation pathways, or extracellular signaling

Highly cited references

Pubmed IDYearTitleCitations
129444852003Megakaryoblastic leukemia 1, a potent transcriptional coactivator for serum response factor (SRF), is required for serum induction of SRF target genes.130
281127372017Pediatric non-Down syndrome acute megakaryoblastic leukemia is characterized by distinct genomic subsets with varying outcomes.61
235315172013NUP98/JARID1A is a novel recurrent abnormality in pediatric acute megakaryoblastic leukemia with a distinct HOX gene expression pattern.58
172830452007Rbm15 modulates Notch-induced transcriptional activation and affects myeloid differentiation.44
271144622016Recurrent abnormalities can be used for risk group stratification in pediatric AMKL: a retrospective intergroup study.33
229279432012Rbm15-Mkl1 interacts with the Setd1b histone H3-Lys4 methyltransferase via a SPOC domain that is required for cytokine-independent proliferation.19
280631902017Prognostic impact of specific molecular profiles in pediatric acute megakaryoblastic leukemia in non-Down syndrome.18
324084942020RNA-Binding Proteins in Acute Leukemias.17
187109512008OTT-MAL is a deregulated activator of serum response factor-dependent gene expression.16
262151112015Heterogeneous cytogenetic subgroups and outcomes in childhood acute megakaryoblastic leukemia: a retrospective international study.15
298067012018Neonatal leukaemia.11
294275262018NUP98-BPTF gene fusion identified in primary refractory acute megakaryoblastic leukemia of infancy.7
213704212011Acute megakaryoblastic leukemia with a four-way variant translocation originating the RBM15-MKL1 fusion gene.5
158497732005RBM15-MKL1 (OTT-MAL) fusion transcript in an adult acute myeloid leukemia patient.5
247437872014Detection of RBM15-MKL1 fusion was useful for diagnosis and monitoring of minimal residual disease in infant acute megakaryoblastic leukemia.3
224699442012Hemophagocytosis by leukemic megakaryoblasts in acute myeloid leukemia (megakaryoblastic) with t(1;22)(p13;q13);RBM15-MKL1.3
284129982017New hPSC-based human models to study pediatric Acute Megakaryoblastic Leukemia harboring the fusion oncogene RBM15-MKL1.2
282396262017Acute Myeloid Leukemia With RBM15-MKL1 Presenting as Severe Hepatic Failure.2
258389022015Neonatal acute megakaryoblastic leukemia mimicking congenital neuroblastoma.2
318026262020Acute megakaryoblastic leukemia with t(1;22)(p13.3;q13.1); RBM15-MKL1 mimicking hepatoblastoma in an infant: The role of karyotype in differential diagnosis.1
360037952022Revealing the intratumoral heterogeneity of non-DS acute megakaryoblastic leukemia in single-cell resolution.0
344972212021[Acute leukemia of infants and neonates].0
358447382022Case Report: The Value of Genomic Analysis in a Case of Megakaryoblastic Leukemia With Atypical Initial Manifestation.0
327438722021TERT promotor variant associated with poor clinical outcome in a patient with novel RBM15-MKL1 fusion-positive pediatric acute megakaryoblastic leukemia.0
325729492020Acute megakaryoblastic leukaemia with t(1;22)(p13·3;q13·1)/RBM15-MKL1 in an adult patient following a non-mediastinal germ cell tumour.0
308423872019[Prognostic significance of chimeric fusion gene analysis in pediatric acute megakaryoblastic leukemia].0
198601792009[Classification of myeloid leukemias].0


No bibliography items were found for this article.


Fusion gene

RBM15/MKL1 RBM15 (1p13.3) MKL1 (22q13.1) M|RBM15/MKL1 RBM15 (1p13.3) MKL1 (22q13.1) M t(1;22)(p13;q13)
Atlas Image
t(1;22)(p13;q13) G- and R- banding


Jean-Loup Huret

t(1;22)(p13;q13) RBM15/MKL1

Atlas Genet Cytogenet Oncol Haematol. 2001-06-01

Online version: http://atlasgeneticsoncology.org/haematological/1005/t(1;22)(p13;q13)

Historical Card

1999-11-01 t(1;22)(p13;q13) RBM15/MKL1 by  Jean-Loup Huret 

Genetics, Dept Medical Information, University of Poitiers, CHU Poitiers Hospital, F-86021 Poitiers France

1998-01-01 t(1;22)(p13;q13) RBM15/MKL1 by  Jean-Loup Huret 

Genetics, Dept Medical Information, University of Poitiers, CHU Poitiers Hospital, F-86021 Poitiers France

1997-08-01 t(1;22)(p13;q13) RBM15/MKL1 by  Jean-Loup Huret,Jean-Loup Huret 

Genetics, Dept Medical Information, University of Poitiers, CHU Poitiers Hospital, F-86021 Poitiers France