The stability of hϵ-globin mRNA is enhanced in β-thalassemic mice. (A) Representative analyses of transgenic hϵ-globin mRNA survival in nonthalassemic and thalassemic mice. Bone marrow (B) and peripheral blood (P) from hϵ-transgenic mice was subjected to RPA using [³²P]-labeled hϵ-globin and control mα-globin RNA probes. The mβ-globin genotypes of individual animals are indicated. Mice were derived from 2 independent transgenic lines (ϵ1, ϵ2). (B) Increased survival of hϵ-globin mRNA in β-thalassemic mice. The results from replicate analyses described in panel A are illustrated; mRNA stability is defined in the legend to Figure 2C. Values from individual animals are plotted (•); bars indicate averages for animals with the stated mβ-globin genotypes. (C) Representative analysis of transgenic hϵ-globin mRNA survival in hβ-expressing transgenic mice. RNAs from mβ^+/−/hϵ mice that did (+) or did not (−) carry an hβ transgene were studied as described in panel A. The positions of the protected probe fragments are indicated. (D) Decreased stability of hϵ-globin mRNA in hβ-expressing transgenic mice. The results from replicate analyses of mβ^+/−/hϵ animals coexpressing an hβ transgene are plotted individually (points) and averaged (⊡). The value for hϵ mRNA in mβ^+/−/hϵ mice that do not express hβ globin is reproduced from panel B (transgenic line e2).