Rabbit globin pseudogene psi beta 2 is a hybrid of delta- and beta-globin gene sequences.
The evolutionary history of the rabbit globin pseudogene psi beta 2 was studied by completing its nucleotide sequence and aligning the sequence with that of the rabbit adult globin gene beta 1 and the human minor adult globin gene delta. The 5' flanking region and exon 1 of psi beta 2 were most similar to rabbit beta 1, but the large intervening sequence and the 3' untranslated region were most similar to human delta. Intron 1 and exon 2 were equally similar to both delta and beta 1. This pattern indicates that psi beta 2 was originally a delta-like gene that acquired the 5' portion of gene beta 1 by intrachromosomal gene conversion. The presence of a delta-globin gene sequence in both rabbits and humans shows that it is an ancient gene, predating the mammalian radiation that occurred over 85 Myr ago. Delta has shown a pronounced tendency to be altered in its 5' end during the course of mammalian evolution. Quantitative divergence analysis shows that the ancestor to rabbit psi beta 2 was active until 20-30 Myr ago, during which time the lagomorph beta-globin gene family apparently functioned without a pseudogene.
D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D004247:DNA / Q000235:genetics; D005914:Globins / Q000235:genetics; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D011544:Pseudogenes; D011817:Rabbits / Q000235:genetics*
D005914:Globins; D004247:DNA