Chromosomal Changes of Similar Nature in Seven Established Cell Lines Derived From the Peripheral Blood of Patients With Leukemia 2

Seven cell lines derived from the peripheral blood of leukemic patients were examined cytogenetically. All strains had predominantly diploid chromosome numbers. In a few metaphases, incomplete condensation of single chromosomes involved chiefly chromosomes that were affected by secondary constrictions. In anaphase preparations the uncoiled material failed to move in step with the divided chromosomes and was easily detected. Autoradiography with tritiated thymidine revealed DNA synthesis of incompletely condensed material during the G2 period; this indicated a disturbed DNA replication pattern of the involved chromosomes. The implications of these findings are discussed.