FIG. 1.

Structure of the human β-globin locus and minichromosomal locus containing the ɛ-globin gene and LCR HS2. The human β-globin locus is diagrammed across the top of the figure. A domain of histone modification mapped over the LCR and ɛ- and γ-globin genes in K562 cells is indicated by the colored rectangle. LCR HS2 (1.46 kb) was fused to the ɛ-globin gene (3.7 kb) in the minichromosome locus (see Materials and Methods). Two mutant loci were created in which either the HS2 NF-E2 site or the ɛ-globin promoter TATA box was destroyed by clustered point mutations. The positions of TaqMan probes used for real-time PCR are indicted at the bottom.