The αβ-cosmid contains α- and β-globin genes.

Restriction mapping and Southern hybridization were used to determine the location of the β-globin gene, and an area of approximately 35 kb surrounding the gene was sequenced. BLAST searches and alignments revealed the presence of 3 putative globin genes. (A) The α3-, α4-, and β-globin genes are closely linked and directed in opposite transcriptional orientations. Arrows indicate the transcription start sites. Genes are shown as boxes with exons in black. (B) Promoter area of the α3-globin gene and (C) promoter area of the β-globin gene. The beginning of exon 1 is boxed. Putative TATA boxes and an inverted CACC motif are highlighted with a gray background.