2018-03-01   Adriana Zamecnikova 

1.Kuwait Cancer Control Center, Kuwait


The unbalanced der(2)t(1;2)(q12-21;q37) is a rare anomaly in hematological malignancies with unknown clinical significance.

Clinics and Pathology


Acute myeloid leukemia (AML), multiple myeloma (MM) and less frequently lymphoid malignancies.

Phenotype stem cell origin

Myeloid malignancies in 5 (3 males and 2 females): 1 Fanconi anemia patient with refractory anemia (RA) (Huret et al., 1988), 1 AML (Raimondi et al 1999), 1 acute myeloblastic leukemia with minimal differentiation (AML-M0) and 2 acute monoblastic leukemia patients (AML-M5) (Busson Le Coniat et al., 2000; Cerveira et al., 2012).
Multiple myeloma in 8 (3 males and 5 females) (Smadja et al., 2001; Sawyer et al., 2014; Rack et al., 2016).
Lymphoid malignancies in 5 (4 males and 1 female): 2 acute lymphoblastic leukemia (ALL) (1 with 1q12-21 breakpoint) (Busson-Le Coniat et al., 1999; Kim et al., 2011) 2 follicular lymphoma (Gray et al., 1997; Cheung et al., 2012) and 1 diffuse large B-cell lymphoma (DLBCL) (Jerkeman et al., 1999).


10 males and 8 females aged 21 to 81 years (median 69 years); male prevalence in patients with lymphoid malignancies (2 males in ALL and 3 males/1 female in lymphomas), aged 51, 69 and 71 years, 2 unknown. Patient with myeloid malignancies were aged 21, 68, 77 and 81 years, 1 unknown; the age of MM patients is unknown.


The Fanconi anemia patient received androgen therapy. He developed refractory anemia 4 years later that was treated with corticosteroids and antibiotics, but after recurrent infections he died from pneumonia 4 years later. The patient with acute monoblastic leukemia and t(11;19)(q23;p13) was treated with chemotherapy but failed to achieve remission; after receiving allogenic bone marrow transplant he is alive 23+ months. 2 AML patients had highly complex karyotypes, considered as an adverse prognostic factor in AML. Similarly, in patients with MM or lymphoid malignancies and highly complex karyotypes, the prognosis is likely unfavorable.


Cytogenetics morphological

Unbalanced rearrangement resulting in 1q trisomy.

Additional anomalies

Found in association with del(5q) in MDS, 11q23/ KMT2A (MLL)/ MLLT1 in acute monoblastic leukemia, as an additional anomaly to t(9;22) in 1 AML and in both ALL cases and as an additional aberration to t(14;18) in 2 lymphoma patients; found as part of highly complex karyotypes in the remaining patients.

Result of the Chromosomal Anomaly


A non-random structural gain of 1q is a known structural anomaly in hematopoietic malignancies, and it is often the result of an unbalanced chromosome translocation. The breakpoints within 1q show considerable variation from 1q11 to 1q43, with a clustering to 1q12-23. Various unbalanced 1q translocation partners have been described, among them, the der(2)t(1;2)(q12-21;q37) has been detected accompanied with other chromosome abnormalities, therefore it is likely a secondary genetic event. The major consequence of this unbalanced chromosome translocation is the genomic imbalance resulting from the gain of the long arm of chromosome 1q.


Pubmed IDLast YearTitleAuthors
109950102000Interstitial telomere repeats in translocations of hematopoietic disorders.Busson Le Coniat M et al
228467432012Genetic and clinical characterization of 45 acute leukemia patients with MLL gene rearrangements from a single institution.Cerveira N et al
221040782012SNP analysis of minimally evolved t(14;18)(q32;q21)-positive follicular lymphomas reveals a common copy-neutral loss of heterozygosity pattern.Cheung KJ et al
93091141997Fluorescence in situ hybridization assessment of the telomeric regions of jumping translocations in a case of aggressive B-cell non-Hodgkin lymphoma.Gray BA et al
32483781988Karyotype evolution in the bone marrow of a patient with Fanconi anemia: breakpoints in clonal anomalies of this disease.Huret JL et al
100898961999Prognostic implications of cytogenetic aberrations in diffuse large B-cell lymphomas.Jerkeman M et al
215496232011PAX5 deletion is common and concurrently occurs with CDKN2A deletion in B-lineage acute lymphoblastic leukemia.Kim M et al
263388012016Genomic profiling of myeloma: the best approach, a comparison of cytogenetics, FISH and array-CGH of 112 myeloma cases.Rack K et al
105720831999Chromosomal abnormalities in 478 children with acute myeloid leukemia: clinical characteristics and treatment outcome in a cooperative pediatric oncology group study-POG 8821.Raimondi SC et al
244975332014Jumping translocations of 1q12 in multiple myeloma: a novel mechanism for deletion of 17p in cytogenetically defined high-risk disease.Sawyer JR et al
115680112001Hypodiploidy is a major prognostic factor in multiple myeloma.Smadja NV et al


Atlas Image
Partial karyotypes showing the unbalanced rearrangement between chromosomes 1 and 2.


Adriana Zamecnikova


Atlas Genet Cytogenet Oncol Haematol. 2018-03-01

Online version:;2)(q12-21;q37)

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