Figure 2.

Human globin gene expression in βYAC fetuses also carrying a hGATA-1 transgene (+) or lacking a hGATA-1 transgene (−). Expression of the human ɛ, γ, and β genes measured by quantitative RNase protection assay. The results shown here are from the βYAC line A bred with a mouse carrying four copies of the hGATA-1 construct. Similar results were obtained with βYAC transgenic lines B and C. Lanes: B, blood; Y, yolk sac; L, liver. The protected fragment sizes are 206 bp for human β mRNA, 170 bp for γ mRNA, and 188 bp for human ɛ mRNA. Murine (Mu) α and ζ mRNAs are internal controls. hGATA-1-positive or -negative animals in a litter were identified by Southern blot hybridization.