[Current therapeutic targeting possibilities in leukemia]

Investigations on the configuration of immunoglobulin (Ig) and T-cell receptor (TCR) genes have become more and more widespread. Through these methods it is possible to identify malignant clones, which by a transforming event have been blocked in further differentiation but continued to proliferate. Such clonal expansions can be verified by the Southern Blotting procedure as differences in molecular weight between normal and rearranged DNA fragments. In the lymphatic disorders it is possible to assign the malignant clone to B cell lineage by rearrangement in the immunoglobulin light chain gene, while heavy chain and T-cell receptor genes do not show consistency in lineage restriction. In a study on AML patients with solitary expression of the T-cell marker CD7 we have identified a similarity in TCR beta and delta gene configurations, indicating a correlation between etiology and genetic pattern. Such observations can contribute to an elucidation of the malignant blood-diseases and by that a better choice in therapy.