Torque teno virus: its prevalence and isotypes in North India.

AIM To investigate the prevalence and genotype distribution of Torque teno virus (TTV) in patients with different liver diseases and chronic renal failure treated at a referral hospital in North India. METHODS Whereas prevalence of TTV was based on amplification of conserved region of ORF2 of TTV genome, the genotyping of TTV was carried out using restriction fragment length polymorphism (RFLP) procedure on the N22 region of ORF1. RESULTS TTV-DNA was detected in 137 of 513 (26.7%) patients with liver diseases and 38 of 65 (58.5%) patients with chronic renal failure. TTV was also detected in 27% of healthy controls. The sequence analysis of the PCR product from 10 randomly selected cases failed to show a significant sequence divergence when compared with that of the TRM1 isolate of TTV genotype 1. The results of genotyping in 55 randomly selected patients showed the presence of genotype 1 (G1) in 53 (96.4%) and genotype 2 (G2) in 2 cases (3.6%), respectively. Other genotypes were not identified in this patient subgroup, suggesting that G1 is predominant in this area. The results of genotyping by RFLP were also supported by phylogenetic tree analysis, where G1 was found to be the major genotype. CONCLUSION These results indicate that TTV is moderately present in Indian patients, with G1 to be the major genotype in North India. The pathogenicity and etiological role of TTV in different diseases is still a question mark and warrant further studies.

[1]  I. Dhar,et al.  Transfusion-transmitted virus in association with hepatitis A-E viral infections in various forms of liver diseases in India. , 2006, World journal of gastroenterology.

[2]  Y. Saral,et al.  Prevalence and genotypic distribution of hepatitis GB-C/HG and TT viruses in blood donors, mentally retarded children and four groups of patients in eastern Anatolia, Turkey. , 2005, Japanese journal of infectious diseases.

[3]  Mohammad Irshad,et al.  Prevalence of chronic renal failure in adults in Delhi, India. , 2005, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[4]  R. Gupta,et al.  Presence of TT virus infection in chronic hepatitis patients from a hospital in New Delhi, India. , 2005, The Indian journal of medical research.

[5]  J. Qiu,et al.  Human Circovirus TT Virus Genotype 6 Expresses Six Proteins following Transfection of a Full-Length Clone , 2005, Journal of Virology.

[6]  S. Devalle,et al.  Rolling-circle amplification of Torque teno virus (TTV) complete genomes from human and swine sera and identification of a novel swine TTV genogroup. , 2005, The Journal of general virology.

[7]  R. Tachezy,et al.  Age-specific prevalence, transmission and phylogeny of TT virus in the Czech Republic , 2004, BMC infectious diseases.

[8]  U. Akarca,et al.  TT Virus Infection and Genotype Distribution in Blood Donors and a Group of Patients from Turkey , 2002, Infection.

[9]  E. Ok,et al.  GB virus C/hepatitis G virus infection among renal transplant recipients in Izmir, Turkey: Molecular analysis of phylogenetic groups. , 2002, International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases.

[10]  M. Irshad,et al.  Superoxide dismutase and total anti-oxidant levels in various forms of liver diseases. , 2002, Hepatology research : the official journal of the Japan Society of Hepatology.

[11]  S. Hino.  TTV, a new human virus with single stranded circular DNA genome , 2002, Reviews in medical virology.

[12]  T. Nishizawa,et al.  Analysis of the entire genomes of thirteen TT virus variants classifiable into the fourth and fifth genetic groups, isolated from viremic infants , 2002, Archives of Virology.

[13]  G. Antonelli,et al.  Dynamics of Persistent TT Virus Infection, as Determined in Patients Treated with Alpha Interferon for Concomitant Hepatitis C Virus Infection , 2001, Journal of Virology.

[14]  M. Rapicetta,et al.  Prevalence of TT Virus in Healthy Children and Thalassemic Pediatric and Young Adult Patients , 2001, Journal of pediatric gastroenterology and nutrition.

[15]  H. Okamoto,et al.  TT virus: virological and genomic characteristics and disease associations , 2001, Journal of Gastroenterology.

[16]  M. Pistello,et al.  TT virus levels in the plasma of infected individuals with different hepatic and extrahepatic pathology , 2001, Journal of medical virology.

[17]  L. Duret,et al.  Use of a TT virus ORF1 recombinant protein to detect anti-TT virus antibodies in human sera. , 2000, The Journal of general virology.

[18]  Masaharu Takahashi,et al.  Sequestration of TT Virus of Restricted Genotypes in Peripheral Blood Mononuclear Cells , 2000, Journal of Virology.

[19]  T. Nishizawa,et al.  Circular Double-Stranded Forms of TT Virus DNA in the Liver , 2000, Journal of Virology.

[20]  N. Young,et al.  Prevalence of the newly described human circovirus, TTV, in United States blood donors , 2000, Transfusion.

[21]  T. Nishizawa,et al.  The entire nucleotide sequence of a TT virus isolate from the United States (TUS01): comparison with reported isolates and phylogenetic analysis. , 1999, Virology.

[22]  J. Ball,et al.  TT virus infection in patients with hepatitis C: frequency, persistence, and sequence heterogeneity. , 1999, The Journal of infectious diseases.

[23]  A. Yamada,et al.  Identification of a Novel GC-Rich 113-Nucleotide Region To Complete the Circular, Single-Stranded DNA Genome of TT Virus, the First Human Circovirus , 1999, Journal of Virology.

[24]  T. Pilot‐Matias,et al.  Molecular and biophysical characterization of TT virus: evidence for a new virus family infecting humans. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[25]  X. de Lamballerie,et al.  Determination and phylogenetic analysis of partial sequences from TT virus isolates. , 1999, The Journal of general virology.

[26]  R. Ueda,et al.  New genotypes of TT virus (TTV) and a genotyping assay based on restriction fragment length polymorphism 1 , 1998, FEBS letters.

[27]  T. Nishizawa,et al.  Molecular cloning and characterization of a novel DNA virus (TTV) associated with posttransfusion hepatitis of unknown etiology , 1998 .

[28]  T. Nishizawa,et al.  A novel DNA virus (TTV) associated with elevated transaminase levels in posttransfusion hepatitis of unknown etiology. , 1997, Biochemical and biophysical research communications.

[29]  J. Thompson,et al.  The CLUSTAL_X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. , 1997, Nucleic acids research.

[30]  Y. Joshi,et al.  Acute liver failure. Experience with 145 patients. , 1986, Journal of clinical gastroenterology.

[31]  Acute and chronic hepatitis revisited. Review by an international group. , 1977, Lancet.