[Rearrangement of the short arm of chromosome 12 in chronic myelomonocytic leukemias].

A rearrangement of the short arm of chromosome #12 with a breakpoint at band 12 was found in 4 out of 15 patients with CMML: two deletions, one simple translocation (9;12)(p21;p12) and one complex t(11;12;13)(p11;p12;q21). Their haematological and clinical characteristics were investigated together with those of 5 other similar published cases. Although this alteration is not very frequent in this myelodysplastic syndrome, and is also found in various other malignant blood disorders, it is clearly a non-random phenomenon, the consequences of which are discussed.