Human globin transgene mRNA levels in the reticulocytes of β-thalassemic/β-globin transgenic animals.

(A) RNase protection assay using 250 ng RNA and probes for hγ-globin (exon 2) and mα-globin (exon 1). RNA samples obtained from the PB of the following animals were assayed in the same reaction for the amount of each globin mRNA: Lane 1: β-thalassemic littermate without a human globin transgene; lanes 2 and 3: β-thalassemic animals with an ankyrin promoter–γ-globin transgene (strain A); lanes 4 and 5: β-thalassemic animals with a β-spectrin promoter–γ-globin transgene (strain B); lanes 6 and 7: β-thalassemic animals homozygous for the β-spectrin promoter–γ-globin transgene (strain C). The sizes of the protected fragments (indicated by the arrows) are 225 bp for γ-globin and 128 bp for α-globin. (B) RNase protection assay using 250 ng and probes for hβ-globin (exon 1) and mα-globin (exon 1). RNA samples from 2 β-thalassemic animals containing the hβ-globin locus YAC28 (strain D) were assayed for the amount of hβ-globin and mα-globin in separate reactions owing to the similar sizes of the protected fragments for each transcript (135 bp and 128 bp, respectively).