[Acute myelocytic leukemia-1 gene rearrangement in acute myeloblastic leukemia with t(8;21)]

The chromosomal translocation t(8;21) (q22;q22), one of the most important recurrent cytogenetic abnormalities in acute leukemia, is mainly associated with the AML-M2 phenotype. In this study, the chromosome 21 breakpoints in 24 out of 29 patients with acute leukemia and t(8;21) were determined. The breakpoints were clustered within intron 4 of the AML-1 gene in 23 patients, including two with variant translocations, and one with the myelomonocytic subtype of acute leukemia. In one case the breakpoint was located in intron 5. In case 29 with 45, XY, del(8) (q22), -21, i.e. lacking the 21q+chromosome, the AML-1 gene was also rearranged intron 4. This suggests that the rearranged sequence important in this leukemia is located to the del (8) chromosome.