The duplicated human α globin genes lie close together in cellular DNA

Abstract

The organization of α globin genes in normal human DNA was examined by restriction endonuclease mapping, α-globin-specific fragments in endonuclease digests of total cell DNA were identified after electrophoresis by hybridization with [32P]cDNA. The data provide direct evidence for the duplication of α genes and further indicate that these loci are closely linked within a single restriction fragment. The HindIII sites (codons 90/91) of these duplicated genes lie approximately 3.7 kilobases apart in the physical map proposed for this region. This organization of α genes can be altered in DNA of individuals with α-thalassemia.