Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

DNA sequencing studies indicate that only one of two closely linked human embryonic alpha-like globin genes, zeta (zeta), encodes a functional polypeptide. The other is a pseudogene (psi zeta) that differs by only 3 bp in the protein coding sequence, one of which converts the codon for amino acid 6 into a chain termination codon. Both zeta-globin genes differ from all other alpha-like genes thus far reported in that they contain large introns consisting, in part, of simple repeat sequences. Intron 1 of each gene contains a variation of the repeat sequence ACAGTGGGGAGGGG, while intron 2 contains the repeat sequence CGGGG. Comparison of the human zeta- and alpha-globin gene sequences reveals that the embryonic and adult alpha-like genes began to diverge from each other relatively early in vertebrate evolution (400 million years ago). In contrast, the beta-like embryonic globin gene, epsilon (epsilon), is the product of a much more recent evolutionary event (200 million years ago). Thus, even though the temporal and quantitative expression of zeta- and epsilon-globin genes must be coordinately controlled during development, their evolutionary histories are clearly distinct.

Type

Journal article

Journal

Cell

Publication Date

12/1982

Volume

31

Pages

553 - 563

Keywords

Amino Acid Sequence, Animals, Base Sequence, Biological Evolution, Cloning, Molecular, Codon, DNA Restriction Enzymes, Embryo, Mammalian, Female, Genes, Globins, Humans, Pregnancy, RNA, Messenger, Species Specificity