Chromosome Translocations and Human Cancer1

quent findings that the great majority of human hematopoietic malignancies carry specific chromosomal alterations (3, 4) have suggested that such nonrandom chromosomal changes may be involved in the pathogenesis of human malignancies. This view, however, was not shared by many investigators outside the field of cancer cytogenetics, who regarded such chromosomal alter ations as epiphenomena of the neoplastic process. Recent developments in the analyses of genes involved in the chromosomal rearrangements observed in human leukemias and lymphomas indicate that such rearrangements are the critical steps involved in the pathogenesis of most human leukemias and lymphomas and that they may also play an important role in the pathogenesis of human solid tumors.