[Modifications of genetic markers during malignant blood disease].

Genetic marker changes in malignancy are related to an acquired disfunction of the genetic material in stem cells. This disfunction always leads to the lack of antigen; whenever we evidenced a new specificity it was an unconverted substrate. In malignant states modifications are multiple, polyclonal and independent. This least feature explains the extent of the process giving that disfunction. The evidence of a genetic defect is supported by the simultaneous decrease of the primary gene product: the glycosyl-transferase (ABO locus). In some other malignant carcinoma, blood group specificities were observed, their meaning is not well explained. Blood group specificities associated to carcino embryogenic antigen (CEA) or to some mucins could be related to the structure of macromolecular carriers.