Cell September 1, 1980; 21 (2): 555-64.

Linkage of adult alpha- and beta-globin genes in X. laevis and gene duplication by tetraploidization.

Abstract
We have used cloned adult X. laevis alpha- and beta-globin cDNAs to analyze globin genes in X. laevis DNA. We detected alpha 1- and beta 1-globin genes which contain intervening sequences and code for the major adult globins, plus additional diverged alpha 2- and beta 2-globin genes of unknown coding potential. Unlike the case in mammals, the X. laevis alpha 1- and beta 1-globin genes are closely linked and occur in the sequence 5''-alpha 1-9 kb-beta 1-3''. The alpha 2- and beta 2-globin genes are also linked, and analysis of globin genes in X. tropicalis suggests that this duplication of an alpha-beta-globin gene pair in X. laevis is the result of chromosome duplication by tetraploidization. The close linkage of alpha- and beta-globin genes in Xenopus provides evidence that vertebrate alpha- and beta-globin genes evolved by tandem duplication of a single primordial globin gene.

PubMed ID: 7407927
Article link: Cell


Species referenced: Xenopus laevis
Genes referenced: hbg1