title: Phylogenetic relationships within the genus Equus and the evolution of alpha and theta globin genes.
abstract: Sequences of the alpha1, alpha2 and theta globin genes from six equid species have been determined to investigate relationships within the genus Equus. Analyses using standard phylogenetic methods, or an approach designed to account for the effects of gene conversion between the alpha genes, gave broadly similar results and show that the horses diverged from the zebra/ass ancestor approximately 2.4 million years ago and that the zebra and ass species arose in a rapid radiation approximately 0.9 million years ago. These results from the alpha genes are corroborated by theta gene data and are in contrast to mitochondrial DNA studies of the phylogeny of this genus, which suggest a more gradual set of speciation events.
authors.affiliation: Institute of Molecular Medicine, University of Oxford, Oxford, UK. a.oakenfull@gen.cam.ac.uk
authors.forename: E A
authors.initials: EA
authors.lastname: Oakenfull
authors.forename: J B
authors.initials: JB
authors.lastname: Clegg
mesh_terms: D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D018397:Equidae / Q000235:genetics*; D019143:Evolution, Molecular; D005785:Gene Conversion; D005914:Globins / Q000235:genetics*; D006736:Horses / Q000235:genetics*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D013997:Time Factors
chemical_list: D017931:DNA Primers; D005914:Globins; D004247:DNA