title: Analysis of the entire genomes of torque teno midi virus variants in chimpanzees: infrequent cross-species infection between humans and chimpanzees.
abstract: Humans are frequently infected with three anelloviruses which have circular DNA genomes of 3.6-3.9 kb [Torque teno virus (TTV)], 2.8-2.9 kb [Torque teno mini virus (TTMV)] and 3.2 kb [a recently discovered anellovirus named Torque teno midi virus (TTMDV)]. Unexpectedly, human TTMDV DNA was not detectable in any of 74 chimpanzees tested, although all but one tested positive for both human TTV and TTMV DNA. Using universal primers for anelloviruses, novel variants of TTMDV that are phylogenetically clearly separate from human TTMDV were identified from chimpanzees, and over the entire genome, three chimpanzee TTMDV variants differed by 17.9-20.3 % from each other and by 40.4-43.6 % from all 18 reported human TTMDVs. A newly developed PCR assay that uses chimpanzee TTMDV-specific primers revealed the high prevalence of chimpanzee TTMDV in chimpanzees (63/74, 85 %) but low prevalence in humans (1/100). While variants of TTV and TTMV from chimpanzees and humans were phylogenetically interspersed, those of TTMDV were monophyletic for each species, with sequence diversity of <33 and <20 % within the 18 human and three chimpanzee TTMDV variants, respectively. Maximum within-group divergence values for TTV and TTMV were 51 and 57 %, respectively; both of these values were substantially greater than the maximum divergence among TTMDV variants (44 %), consistent with a later evolutionary emergence of TTMDV. However, substantiation of this hypothesis will require further analysis of genetic diversity using an expanded dataset of TTMDV variants in humans and chimpanzees. Similarly, the underlying mechanism of observed infrequent cross-species infection of TTMDV between humans and chimpanzees deserves further analysis.
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi-Ken 329-0498, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Ninomiya
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi-Ken 329-0498, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi-Ken 329-0498, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Hoshino
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi-Ken 329-0498, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Ichiyama
authors.affiliation: Virus Evolution Group, Centre for Infectious Diseases, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Simmonds
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi-Ken 329-0498, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Okamoto
mesh_terms: D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004266:DNA Virus Infections / Q000097:blood / Q000453:epidemiology / Q000635:transmission* / Q000821:virology; D004279:DNA, Viral / Q000097:blood / Q000235:genetics; D018562:Disease Transmission, Infectious; D014644:Genetic Variation; D016679:Genome, Viral; D006801:Humans; D008969:Molecular Sequence Data; D002679:Pan troglodytes / Q000821:virology; D010802:Phylogeny; D015995:Prevalence; D022783:Torque teno virus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D014764:Viral Proteins / Q000235:genetics
chemical_list: D004279:DNA, Viral; D014764:Viral Proteins