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TTV, a new human virus with single stranded circular DNA genome

Shigeo Hino1

  • 1Department of Virology, School of Medicine, Faculty of Medicine, Tottori University, 86 Nishi, Yonago 683-8503, Japan. hino@grape.med.tottori-u.ac.jp

Reviews in Medical Virology
|May 3, 2002
PubMed

Insights

TorqueTenoVirus (TTV), a human virus with a single-stranded DNA genome, remains poorly understood due to limited cell systems. This review summarizes current knowledge on TTV biology, taxonomy, and prevalence across species.

Area of Science:

  • Virology
  • Molecular Biology
  • Genomics

Background:

  • TT virus (TTV) was discovered in 1997, but its impact on liver diseases remains uncertain.
  • The lack of suitable cell culture systems has hindered research into TTV biology.
  • TTV is the first identified human virus with a single-stranded circular DNA genome.

Purpose of the Study:

  • To review the current understanding of TorqueTenoVirus (TTV) beyond its taxonomic diversity.
  • To consolidate information on TTV's genome, prevalence, transmission, and gene expression.

Main Methods:

  • Literature review of existing studies on TTV.
  • Analysis of TTV genome structure and comparison with related viruses.
  • Summary of epidemiological data on TTV prevalence and transmission.

Main Results:

  • TTV's genome is single-stranded DNA, with proposed classification in the new family Anelloviridae.
  • TTV is prevalent in various animal species, including non-human primates, chickens, pigs, cows, and sheep.
  • TTV exhibits mother-to-child transmission, with prevalence equalizing within a year regardless of maternal status.

Conclusions:

  • TTV biology remains largely obscure, necessitating further research.
  • The proposed nomenclature includes TorqueTenoVirus (TTV) and TorqueTenoMiniVirus (TTMV).
  • Further investigation is required to elucidate the functions of TTV-encoded proteins and its role in human health.

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