Cloning and characterization of DNA sequences surrounding the human gamma-, delta-, and beta-globin genes.

Abstract

The human .gamma., .delta., and .beta.-globin genes are located within a 30 kilobase (kb) region of DNA, of which only 20% represents the globin genes. The nature of flanking and intergenic sequences was determined by isolating recombinants containing the human .epsilon., both .gamma.-, or the 3'' end of the .beta.-globin gene from a bacteriophage library of cloned human DNA. These recombinants and a recombinant containing the .delta. and .beta.-globin genes (H.beta.G1) were compared. The .epsilon.-globin gene is located 14 kb 5'' to the G.gamma. gene. DNA sequence homology between the region containing the 2 G.gamma. genes and the .delta. and .beta. gene region is limited to only a few hundred nucleotides which include the globin coding sequences. Repetitive DNA sequences were found in the region 3'' to the .beta.-globin gene. Sequences located adjacent to the .beta.-globin gene are repeated in the globin gene region. A repetitive DNA sequence more than 3.2 kb long is repeated frequently in the human genome but is not repeated in the globin gene region in the clones examined.