Dense red cells in beta thalassemia

Analysis of the density distribution of normal erythrocytes (A), erythrocytes from a nonsplenectomized individual with beta-thalassemia intermedia (B), erythrocytes from a splenectomized individual with beta thalassemia intermedia (C), and HbH erythrocytes (D) on discontinuous Stractan density gradients. The more dense cells are at the bottom of the gradient; dense populations are present only in the nonsplenectomized and splenectomized subjects with beta thalassemia.