title: [Distribution of TT virus genotypes and genogroups in 69 healthy and 59 hepatitis B virus infected Korean individuals].
abstract: BACKGROUND
  TT virus (TTV) infection is highly prevalent in general population and patients with hepatitis B virus (HBV) infection. The aim of the present study was to determine the distribution of the genotypes and genogroups of TTV in healthy and HBV-infected individuals in Korea.
  
  
  METHODS
  Distribution of TTV genotypes and genogroups was investigated in the serum samples of 69 healthy and 59 HBV-infected individuals. PCR products of N22 region were genotyped by sequence analysis. TTV genogroups were determined by 5 different genogroup-specific PCR assays.
  
  
  RESULTS
  Among the 20 sequenced isolates, 9 (45%) were genotype 2, 8 (40%) were genotype 1, 2 (10%) were genotype 3, and 1 (5%) was genotype 4. TTV genogroup 4 was found most frequently (52/128), followed by genogroup 3 (42/128), genogroup 1 (35/128), genogroup 5 (32/128), and genogroup 2 (1/128). Mixed infections with different genogroups were frequent.
  
  
  CONCLUSIONS
  TTV genotype 2 and 1 are predominant genotypes. TTV genotype 3 was detected for the first time in Korea. TTV genogroups 4 and 3 were predominant genogroups. No significant difference was observed in the distribution of TTV genogroups between healthy and HBV-infected individuals.
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Anyang, Korea. kimhan@hallym.ac.kr
authors: Han Sung
authors: HS
authors: Kim
authors: Jae Seok
authors: JS
authors: Kim
authors: Min Jung
authors: MJ
authors: Park
authors: Wonkeun
authors: W
authors: Song
authors: Hee Jung
authors: HJ
authors: Kang
authors: Kyu Man
authors: KM
authors: Lee
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D004266:DNA Virus Infections / Q000175:diagnosis / Q000821:virology*; D005260:Female; D005838:Genotype; D006509:Hepatitis B / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D022783:Torque teno virus / Q000145:classification / Q000235:genetics*