Torque teno virus: a ubiquitous virus
نویسنده
چکیده
Torque teno virus (TTV) is a non-enveloped human DNA virus isolated by Nishizawa et al. in 1997.1 TTV, recently classified as the Alphatorquevirus genus within the Anelloviridae family by the International Committee on Taxonomy of Viruses (ICTV), was the first human virus with a single-stranded circular DNA genome to be identified.2 Thus far, five main genetic groups (Groups 1–5) involving at least 39 genotypes have been identified based on phylogenetic analysis.3 The TTV genome can be divided into an untranslated region (UTR) of 1.2 kb and a potential coding region of 2.6 kb. The UTR is relatively conserved, suggesting that it plays an important regulatory role in viral replication. The coding region contains two large open reading frames: ORF1 and ORF2. Several other open reading frames have been described, and the peptides that they encode differ in length for different isolates.4 This virus is characterized by an extremely high prevalence, with relatively uniform distribution worldwide and a high level of genomic heterogeneity.4 Although this virus has a very high prevalence in the general population across the globe, neither its interaction with its hosts nor its direct involvement in the etiology of specific diseases is fully understood. After the discovery of TTV, its detection has been by polymerase chain reaction (PCR) with primers targeting the ORF1 (N22 region, the first described sequence), nevertheless primers derived from the N22 region can detect only a portion of TTV variants mainly representing genetic group 1 TTV (Genotypes 1–6).5,6 As the UTRs of the viral genome are more conserved when compared to the ORF regions, UTR-targeting primers (used later for the detection of TTV DNA) can detect
منابع مشابه
Frequency of Torque Teno Mini Virus in Hepatitis B and C Patients and Healthy Blood Donors in Isfahan, Iran
Background: Recently, some new viruses have been identified for their association with hepatitis which Torque Teno Mini Virus being among them. The aim of this study was to determine the frequency of Torque Teno Mini Virus in healthy individuals and hepatitis B and C patients in Isfahan, Iran. Materials and Methods: One hundred serum samples of healthy individuals from Isfahan Blood Transfusi...
متن کاملPrevalence of Torque Teno Virus in Healthy Individuals and Peoples Infected with Hepatitis C Virus Living in Yazd, Iran
متن کامل
Detection of torque teno virus (TTV) in domestic village chickens in Iran
Torque teno virus (TTV) is prevalent worldwide and has been extensively studied in human and some wild and domestic animals. As the studies on TTV in chickens was rare and there was no information about the infection of domestic village chickens with TTV and also structural resemblance of this virus to chicken anemia virus, the frequency of the infection in domestic village chickens in differen...
متن کاملDetection of Torque teno midi virus/Small anellovirus (TTMDV/SAV) in the sera of domestic village chickens and its vertical transmission from hen to eggs
Although the infection of different animals and non-human primates with other members of Anelloviridae have already been reported there is no report about infection of animals with Torque teno midi virus/Small anellovirs (TTMDV/SAV). The aim of this study was to detect the virus in domestic village chickens. Blood samples were collected from 79 domestic village chickens in Isfahan. Blood sample...
متن کاملPrevalence and Genotyping of Torque Teno Virus in HBV/HIV and Chronic HBV Patients in Iran
Background: Torque teno virus (TTV) was the first human Anelloviridae detected in a Japanese patient with an unknown type of hepatitis in 1997. TTV is by far the first known single-stranded circular DNA virus infecting human. In spite of its widespread nature in human population, its pathogenesis is still unclear. In addition, information regarding TTV infection in Iranian population is limited...
متن کاملTorque Teno Virus (TTV) Among β-Thalassemia and Haemodialysis Patients from Mazandaran Province (North of Iran)
Torque Teno virus (TTV) is a transfusion transmitted virus that seems to be involved in several complications such as acute respiratory diseases, liver diseases, AIDS, cancer, and autoimmune reactions. In the present study the frequency of TTV was investigated among β- thalassemia (BT) and haemodialysis (HD) patients (high risk patients for TTV) in Mazandaran province, Iran. DNA was ...
متن کامل