Cell-specific expression of the human δ-globin gene 5′ flanking sequence. (A) β-Like globin gene arrangement on chromosome 11. (B) Promoter region of the human δ-globin gene and possible binding sites of transcription factors. (C) Relative LUC activity of the serial deletion plasmids. The left panel shows human δ-globin promoter-LUC deletion plasmids. The right panel is the relative LUC activity of each plasmid. Data represent the mean ± SD of three individual experiments using three different plasmid DNA preparations.