2007-08-01   Adriana Zamecnikova 

1.Kuwait Cancer Control Center, Laboratory of Cancer Genetics, Department of Hematology, Shuwaikh, 70653, Kuwait

Clinics and Pathology


Myeloid lineage, found in 1 myelodysplastic syndrome (MDS) and 1 Acute Myeloid Leukemia (AML)

Phenotype stem cell origin

MDS-RA and M1 AML by FAB criteria, a primitive myeloid progenitor is likely to be involved


No known prior exposure


Only 2 cases to date, a 69 yr old female and a 31 yr old male, sex ratio 1M/1F


Elevated WBC (68x109/l), 93% blasts in blood, lymphadenopaty, hepatosplenomegaly, high LDH in AML patient


Positive for CD 34, HLDR, CD33, CD68, MPO in AML


Chemotherapy followed by bone marrow transplantation in AML


After the first cycle of therapy, persistent bone marrow infiltration with 11% blasts


Survival 6 month in MDS, 15 month+ in AML


Cytogenetics morphological

May be misinterpreted as t(3;5) in suboptimal preparations

Cytogenetics molecular

FISH analysis is recommended to exclude the more frequent t(3;5)
Atlas Image
FISH with WCP 3 and 4 and LSI BCL6 and 5q EGR1 probes.

Additional anomalies

t(3;4)(p21;q34) is part of a complex karyotype in MDS case associated with del(20q), sole abnormality in AML case

Genes Involved and Proteins

3p21 is a recurrent breakpoint in MDS/AML and t-MDS/t-AML suggesting, 3p21 site is likely to contain a gene (genes) involved in the pathogenesis of t(3;4)(p21;q34). Frequent deletion or allelic loss of band 3p21 is common in solid tumors, indicating the presence of tumor suppressor genes on this chromosome arm. The association among structural chromosome 3 aberrations and fragile sites on 3p may indicate the importance of previous mutagen exposure in the etiology of these diseases.
Although several cancer-related genes have been located to 3p21, no gene has yet been identified to be related with hematological malignancies. One of the candidate genes may be the AF3p21 gene, a novel fusion partner of the MLL gene described in a patient who had developed therapy-related leukemia with t(3;11)(p21;q23). AF3p21 encodes a protein localized exclusively in the cell nucleus, suggesting the possibility that AF3p21 protein plays a role in signal transduction in the nucleus.


Pubmed IDLast YearTitleAuthors
112417892001Genomic organization, tissue expression, and cellular localization of AF3p21, a fusion partner of MLL in therapy-related leukemia.Hayakawa A et al
170745852006Risk factor analysis in myelodysplastic syndrome patients with del(20q): prognosis revisited.Liu YC et al
106484232000Novel SH3 protein encoded by the AF3p21 gene is fused to the mixed lineage leukemia protein in a therapy-related leukemia with t(3;11) (p21;q23).Sano K et al
897638919963p21 is a recurrent treatment-related breakpoint in myelodysplastic syndrome and acute myeloid leukemia.Shi G et al


Atlas Image
t(3;4)(p21;q34) G-banding


Adriana Zamecnikova


Atlas Genet Cytogenet Oncol Haematol. 2007-08-01

Online version: http://atlasgeneticsoncology.org/haematological/1433/t(3;4)(p21;q34)