The degree of correction of anemia in β-thalassemic animals as a function of the level of human globin transgene expression.

The PB Hb concentration is shown for each of the following strains of β-thalassemic animals characterized by the indicated ratios of hγ-globin/mα-globin mRNA: strain A (0.03; n = 11); strain B (0.07; n = 27); and strain C (0.13; n = 9). Strain D thalassemic animals (n = 7) have an hβ-globin/mα-globin mRNA ratio of 0.38. Hb concentrations for control littermate β-thalassemic (THAL; n = 24) and wild-type (WT; n = 52) animals are also shown. The data represent the mean and SEM of Hb concentration for each strain. Strain A differed significantly from THAL (P < .005), as did strains B, C, and D (P < .0001). Strain D and WT animals did not significantly differ in Hb concentration (P = .11).