Expression of fragile site 8q22 in peripheral blood lymphocytes taken from patients with acute leukemia M2 having t(8;21)(q22;q22).

The relation between the expression of common fragile sites and chromosomal breakpoints in neoplastic cells in the same patients has not been well studied. In the present study, the frequency and distribution of aphidicolin-induced breaks on chromosomes 8 and 21 in peripheral blood lymphocytes (PBL) taken from three patients with acute myeloid leukemia, French-American-British classification type M2, having chromosomal translocation t(8;21)(q22;q22) (M2t) were studied prior to any initial treatment. Seven patients with other types of acute leukemia without t(8;21) and 13 healthy people were also studied. In PBL from patients with M2t, the numbers of chromosomal breaks were 1, 7 and 3/216 metaphasees at bands 8q21, 8q22 and 8q24, respectively; the frequencies at 8q22 and 8q24 being significantly higher than those for patients with the other leukemias and for the healthy subjects (p less than 0.001 and p less than 0.01, respectively). These results suggest that the fragility on chromosome 8q21-24 is related to a predisposition to this particular type of leukemia.