FROM MOLECULAR-GENETIC BACK TO CELL DYSFUNCTION AND THE UNDERSTANDINGOF HEMATOLOGIC CANCERS - EXAMPLES OF TRANSLOCATION-T(9-22) AND TRANSLOCATION-T(8-14)

Until recently the classification and the understanding of the maligna nt diseases in haematology were based on cell morphology. After the in itial finding of Philadelphia chromosome in leukemia and translocation t(8,14) in Burkitt lymphoma, several chromosomal abnormalities were i dentified. These analysis in conjunction with the use of membrane mark ers, led to new classifications of these cancers. Thereafter with clon ing and sequencing procedures it was possible to define the diseases a t the DNA level. In this paper we present the evolution of ideas in th at field during the last 20 years. After a period based purely on morp hological description, haematologic cancers are now interpreted in ter ms of deregulation of various cell functions.