title: The selection and evolution of viral quasispecies in HIV-1 infected children.
abstract: OBJECTIVE
  To analyse the diversity and divergence of the viral populations in three mother-child pairs in longitudinally obtained samples for up to 7 years.
  
  
  METHODS
  Peripheral blood mononuclear cells were obtained from three mothers at delivery and three to four samples were obtained from each of their children from 1.5 months up to 78 months of age. The V3 region of HIV-1 was amplified by polymerase chain reaction, cloned and sequenced. HIV-1 DNA sequence comparisons were performed by phylogenetic analysis.
  
  
  RESULTS
  The viral population was initially homogenous in two children but highly heterogeneous in one child. Three patterns of vertical transmission seemed to have occurred: transmission of the most prevalent maternal strain, of a minor maternal strain and of multiple maternal strains. In one child, a possible reappearance of a maternal sequence was observed at 34 months of age.
  
  
  CONCLUSIONS
  Children may become infected with the most prevalent maternal strain, a minor maternal variant or multiple maternal quasispecies. Maternal viral variants may reappear in children after several years of infection and could possibly be derived from a reservoir of founder quasispecies established during the children's primary HIV-1 infection.
authors.affiliation: Divisions of Clinical Virology, Huddinge University Hospital, Karolinska Institutet, Stockholm, Sweden. Piotr.Nowak@impi.ki.se
authors.forename: P
authors.initials: P
authors.lastname: Nowak
authors.forename: A C
authors.initials: AC
authors.lastname: Karlsson
authors.forename: L
authors.initials: L
authors.lastname: Naver
authors.forename: A B
authors.initials: AB
authors.lastname: Bohlin
authors.forename: A
authors.initials: A
authors.lastname: Piasek
authors.forename: A
authors.initials: A
authors.lastname: Sönnerborg
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000821:virology; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000235:genetics; D015658:HIV Infections / Q000235:genetics / Q000635:transmission / Q000821:virology*; D015497:HIV-1 / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D008137:Longitudinal Studies; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D010802:Phylogeny; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood; D012641:Selection, Genetic; D017386:Sequence Homology, Amino Acid
chemical_list: D004279:DNA, Viral; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments; D012367:RNA, Viral