Staining of cytocentrifuged preparations of marrow cells harvested from GATA-1^low (right) and normal (left) littermates.

(A) May-Grünwald staining; 25 × magnification. (B) Propidium iodide staining (negative controls); 25 × magnification. (C) TUNEL staining; 25 × magnification except for the small insert of the GATA-1^low mice, which is 40 × to show the prevalent perinuclear localization of the DNA breaks in the TUNEL-positive cells.