ISOLATION OF THE CHICKEN BETA-GLOBIN GENE AND A LINKED EMBRYONIC BETA-LIKE GLOBIN GENE FROM A CHICKEN DNA RECOMBINANT LIBRARY

A library of random chicken DNA fragments, 15-22 kb long, has been prepared in the vector λ Charon 4A. This library was screened with combined adult and embryonic globin cDNA, and several independent globin gene-containing recombinants were isolated. One of these recombinants, λ Chicken β-globin 1 (λCβG1), contains the adult chicken β-globin gene and a closely linked embryonic β-like globin gene. Both genes are transcribed in the same direction with the adult gene located 5′ to the embryonic gene. Electron microscopic visualization of R loop structures generated by hybridization of globin RNA to λCβG1 demonstrates that both globin genes contain major intervening sequences about 800 bp long, similar to those present in mammalian β-globin genes. The adult β-globin gene also contains a minor (approximately 100 bp long) intervening sequence analogous to the one observed in mammalian β-globin genes. Restriction enzyme analysis of the adult β-globin gene on λCβG1 is consistent with the hypothesis that its two intervening sequences occur in the same positions with respect to the β-globin amino acid sequence as do the corresponding mammalian intervening sequences. © 1979.