Primer extension analysis of RNA from peripheral blood samples. RNA samples were obtained from peripheral blood of mice after transplantation with transduced marrow or fetal liver cells. Primer extension analysis was performed using one primer specific for mouse β-globin major and one specific for human β-globin. Lanes 1 through 3 are samples from mice transplanted with β-globin transduced marrow; lanes 4 through 13 represent samples from mice transplanted with β-globin transduced fetal liver cells; lanes 14 and 15 are negative controls and lane 16 represents positive control RNA obtained from a mouse transgenic for multiple copies of the human β-globin gene.24 The arrows at the left of the figure indicate the predicted positions for human β-globin (Hum β) and mouse β-globin (M βmaj). Size markers are noted on the right side of the figure. Positive signals are seen in the mouse blood samples in lanes 1, 3, and 5. The RNA sample in lane 1 is from mouse 4 in Fig 4; the sample in lane 3 is from mouse 3 in Fig 4.
