title: Human endogenous retrovirus type I-related viruses have an apparently widespread distribution within vertebrates.
abstract: Retroviruses from lower vertebrate hosts have been poorly characterized to date. Few sequences have been isolated, and those which have been reported are all highly divergent when compared to the retroviruses known to be harbored by mammals and birds. Here we show that retroviruses with significant homology to the human endogenous retrovirus type I (HERV-I) are present within the genomes of fish, reptiles, birds, and mammals and that they may well be widespread within many vertebrates. Phylogenetic analysis of nucleotide sequences strongly supported the inclusion of viruses from each of these vertebrate classes into one monophyletic group. This analysis also demonstrated that the HERV-I-related viruses are more closely related to retroviruses belonging to the murine leukemia virus genus than to members of the other retroviral genera. The presence of HERV-I-related retroviruses in so many disparate vertebrate hosts suggests that other endogenous human retroviruses may also have a much wider distribution than is currently appreciated.
authors.affiliation: Department of Biology, Imperial College, Ascot, Berkshire, United Kingdom.
authors.forename: J
authors.initials: J
authors.lastname: Martin
authors.forename: E
authors.initials: E
authors.lastname: Herniou
authors.forename: J
authors.initials: J
authors.lastname: Cook
authors.forename: R
authors.initials: R
authors.lastname: Waugh O'Neill
authors.forename: M
authors.initials: M
authors.lastname: Tristem
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001717:Birds / Q000821:virology; D015139:Blotting, Southern; D004279:DNA, Viral; D005399:Fishes / Q000821:virology; D006801:Humans; D008394:Marsupialia / Q000821:virology; D008969:Molecular Sequence Data; D010802:Phylogeny; D012194:RNA-Directed DNA Polymerase / Q000235:genetics; D012104:Reptiles / Q000821:virology; D012190:Retroviridae / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
chemical_list: D004279:DNA, Viral; D012194:RNA-Directed DNA Polymerase