Torque teno midi virus (TTMDV) is a member of the genus Gammatorquevirus in the family Anelloviridae.
TTMDV, which stands for transfusion transmitted midi virus or torque teno midi virus was first isolated in 2005 from patients with an acute viral infection syndrome.
Because of the circular nature of its DNA genome, TTMDV (which was provisionally named small anellovirus 1) was classified as an anellovirus. Genomic analysis confirmed this classification.
Like other anelloviruses, TTMDV is quite common, even in healthy individuals. It has been found in various bodily fluids, including saliva and nasopharyngeal aspirates.
Genome and capsid
Like other members of its family, TTMDV's genome is a circular single-stranded piece of DNA of a negative polarity. The genome is approximately 3.2 kb in length, which is slightly smaller than that of TTV and slightly larger than that of TTMV. it is a non-enveloped virus with a capsid of about 40 nm in diameter. The capsid possesses T=1 icosahedral symmetry.
The genomes of TTMDV, TTMV, and TTV are similar. The main differences are illustrated by Okamato 2009.
The pathogenic effects of TTMDV in humans is not known. However, it has been isolated from diarrhea.
^ Jones, M.S.; Kapoor, A.; Lukashov, V.V.; et al. (2005). "New DNA viruses identified in patients with acute viral infection syndrome". Journal of Virology. 79 (13): 8320–8326. doi:10.1128/JVI.79.13.8230-8236.2005. PMC 1143717. PMID 15956568.
^ Andreoli, E.; Maggi, F.; Pistello, M.; et al. (2006). "Small anellovirus in hepatitis C patients and healthy controls". Emerging Infectious Diseases. 12 (7): 1175–1176. doi:10.3201/eid1207.060234. PMC 3291067. PMID 16848049.
^ "History of Discoveries and Pathogenicity of TT Viruses." Current Topics in Microbiology and Immunology 331 (2009): 1-20. Springer Link. Web. 26 April 2015.
^ Finkbeiner." Ed. Edward C. Holmes. PLoS Pathogens 4.2 (2008): E1000011., Stacy R.; Allred, Adam F.; Tarr, Phillip I.; et al. (2008). Holmes, Edward C. (ed.). "Metagenomic Analysis of Human Diarrhea: Viral Detection and Discovery". PLOS Pathogens. 4 (2): e1000011. doi:10.1371/journal.ppat.1000011. PMC 2290972. PMID 18398449.