Correction of β-thalassemic red cell morphologic abnormalities as a function of the level of human globin transgene expression.

Wright-Giemsa–stained PB smears from wild-type (panel A) and β-thalassemic (panel B) littermate controls are shown (250 × magnification) along with smears from strain A (panel C), strain B (panel D), strain C (panel E), and strain D (panel F).