Frequency of TEL/AML1 and BCR/ABL fusion genes in children with acute lymphoblastic leukemia

t(12;21) (p12;q22) and t(9;22) (q34;q11) translocations have prognostic significance in acute lymphoblastic leukemia (ALL). The fusion genes TEL/AML1 y BCR/ABL, generated by these translocations, can be easily detected using molecular biology technique. To study the frequency of TEL/AML1 y BCR/ABL fusion genes in children with ALL. Fifty-six children with ALL (age range 1 month- 14 years) were studied, thirty-eight from our Temuco Hospital and 18 from the Metropolitan Region. TEL/AML1 y BCR/ABL fusion genes were detected in bone marrow samples using a reverse transcriptase nested polymerase chain reaction (RT-PCR). TEL/AML 1 and BCR/ABL fusion gene transcripts were detected in 13 (23%) and 2 (4%) children, respectively. No differences in survival were observed between children with positive or negative transcripts for TEL/AML1 fusion gene. However, those positive for BCR/ABL fusion gene, had a significantly lower survival. The frequency of TEL/AML1 and BCR/ABL fusion gene transcripts in these children with ALL is similar to that described by other authors.