Complete or partial trisomy for the long arm of chromosome 1 in patients with various hematologic malignancies.

This study contains data obtained from a cytogenetic investigation of six patients with acute and chronic leukaemia. The karyotypes of bone marrow or blood cells of these patients showed a partial or complete trisomy for the long arm of chromosome 1. Three observations revealed a pronounced resistance of cell clones with 1q+ towards cytostatic therapy, and a comparatively short life span of patients after detection of 1q+. The importance of these changes for the role of some chromosomes and chromosome loci in leukaemogenesis is discussed.