Microchromosomes in human preleukemia and leukemia

This is the authors' abstract. We don't add key points for this paper.

Microchromosomes have been observed in direct bone-marrow chromosome preparations in 9 patients. Seven of these patients had overt myelomonocytic leukemia, one had a preleukemic syndrome initially and subsequently had acute leukemia, and one is believed to be in the preleukemic phase of myelomonocytic leukemia. It is suggested that the microchromosomes in these cases are marker chromosomes which identify a clone or clones of leukemic cells. Microchromosomes appear to be frequent findings in myelomonocytic leukemia.