[Characteristics of DNA replication of the chromosomes of the bone marrow cells in patients with acute leukemia].

A study of the late DNA replication pattern in chromosomes of human acute leucaemia cells revealed a significant diffrence from control. Chromosomes, 2,3 and 4-5 of the acute leucaemia cells finish their DNA replication earlier, and chromosomes 1, 13-15 and 16 later, compared to the control chromosomes. The difference in the pattern of DNA replication between analogous chromosomes of acute leucaemia and donor cells was associated with the discovery of large late-replicating chromatin blocks in the pericentromeric regions of leucaemia cell chromosomes. Some relationship is suggested between the pattern of pericentromeric heterochromatin DNA replication and cell differentiation.