Background: The TEL/AML1 fusion associated with t(12;21)(p13;q22) is the most common gene rearrangement in childhood malignancy, occurring in approximately 25% of pediatric acute lymphoblastic leukemia. The TEL/AML1 rearrangement is cryptic at the cytogenetic level but confers a favorable prognosis. The AML1 gene was first identified by virtue of its involvement in adult and pediatric acute myeloid malignancies associated with t(8;21) and t(3;21)(q26;q22.1). We have therefore determined the frequency of the TEL/AML1 fusion in pediatric myeloid leukemias by RT-PCR analysis.
Methods: Total RNA was isolated from cryopreserved bone marrow samples of 38 pediatric patients with AML. RNA quality was controlled for by amplification of the TEL gene. An RT-PCR assay was then used to test for the presence of the TEL/AML1 fusion.
Results: 29 patients had adequate RNA for analysis. Zero out of 29 pediatric AML patients had evidence for the TEL/AML1 fusion by RT-PCR.
Conclusions: The TEL/AML1 fusion does not occur in children with AML and suggests that the TEL/AML1 rearrangement is restricted in pediatric hematologic malignancy to B lineage ALL.