Several Cell‐Lines with Abnormal Karyotypes in a Patient with Chronic Myelogenous Leukaemia

Chromosome analysis of blood culture and bone marrow mitoses from a patient with chronic myeologenous leukaemia revealed a Ph1-positive cell-line with 45 chromosomes and, later, a series of mutually related lines with 50–53 chromosomes including Ph1. The cell-line with 45 chromosomes was sensitive to therapy, whereas the cells with 50–53 chromosomes seemed to be more or less resistant to the applied drugs. This apparent resistance suggests that these lines may have contributed to the haematologically and clinically poor condition of the patient at the time of their observation. The close relationship among the hyperdiploid cell lines suggests a common origin and gradual evolution of the lines on a selectional basis.