The AML1 Gene in the 8;21 and 3;21 Translocations in Chronic and Acute Myeloid Leukemia

Recurring chromosomal translocations are relatively common in certain neoplasms, particularly leukemias, lymphomas, and some sarcomas (Heim and Mitelman 1987). Cloning of the translocation breakpoints has identified the genes involved in the breakpoint junc-tions, and this in turn has led to a determination f the manner in which the genes are altered. The genes can be altered in the level of their expression or in the properties of the encoded proteins. These alterations appear to play an integral role in the development of the malignant phenotype. In B and T cells, recurring chromosomal transloca-tions disrupt he normal growth regulation by placing a gene important in this regulation under the control of another gene, most often the immunoglobulin genes in