title: Prevalence and genetic diversity of TT virus genotype 21 (YONBAN virus) in Brazil.
abstract: Isolates of the newly characterized, single-stranded DNA virus TTV, have been tentatively classified into four major phylogenetic groups and at least 28 genotypes. Four Japanese isolates, designated as YONBAN viruses, belong to the fourth group and to genotype 21. In this study, a genotype 21-specific PCR assay was standardized. With this assay, 48/184 (26%) serum samples and 76/167 (46%) saliva samples, collected from unselected ambulatory patients (aged 2 to 82) of a Brazilian public hospital, were positive. A total of 110 (66%) patients had TTV genotype 21 DNA in serum, saliva, or both fluids. Furthermore, 18/37 (49%) serum samples, collected from Indians belonging to three ethnic groups of the Western Brazilian Amazon, were also positive. Nucleotide sequences (253 bases at the 3' end of the non-coding region of the genome) were determined, that derived from 25 individuals, i.e. 17 patients and eight Indians. Phylogenetic analysis showed that three isolates from Indians of a particular ethnic group formed a separate subgroup within genotype 21. Among non-Indians, a clustering of strains was observed according to their country of origin (Japan or Brazil), with all 17 sequences derived from Brazilian patients located in a unique subgroup.
authors.affiliation: Department of Clinical Analyses, Federal University of Santa Catarina, Florianópolis, Brazil.
authors.forename: H C F
authors.initials: HC
authors.lastname: Vasconcelos
authors.forename: S A
authors.initials: SA
authors.lastname: Gomes
authors.forename: M
authors.initials: M
authors.lastname: Cataldo
authors.forename: C
authors.initials: C
authors.lastname: Niel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004266:DNA Virus Infections / Q000453:epidemiology* / Q000208:ethnology / Q000821:virology; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006785:Hospitals, University; D006801:Humans; D007199:Indians, South American; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010802:Phylogeny; D015995:Prevalence; D017422:Sequence Analysis, DNA; D022783:Torque teno virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D004279:DNA, Viral