title: Human immunodeficiency virus-1 subtypes and antiretroviral drug resistance profiles among drug-naïve Brazilian blood donors.
abstract: BACKGROUND
  Human immunodeficiency virus-1 (HIV-1) genetic variability and its implication on the development of new reagents were investigated by correlating time of infection and resistance to antiretroviral drugs.
  
  
  METHODS
  Seventy-four plasma samples from Brazilian drug-naïve blood donors were assayed to further develop a panel of biologic reagents to be used in serology and molecular tests. After viral RNA extraction, cDNA was generated and used in nested polymerase chain reaction protocols with primers for the ENV (C2-V3 and gp41), protease (PR), and reverse transcriptase (RT) of HIV-1. Genomic sequencing was conducted to define HIV-1 subtypes and drug resistance mutations.
  
  
  RESULTS
  Subtype B was found in 83.8 percent of all samples, subtype F in 2.7 percent, and BF mosaics in 11 percent of the cases. B and F different genetic profiles were evidenced: B(PR)B(RT)B(gp120)B(gp41), F(PR)F(RT)F(gp120)F(gp41), F(PR)F(RT)B(gp120)B(gp41), F(PR)B(RT)B(gp120)B(gp41), and B(PR)B(RT)F(gp120)B(gp41). A single sample (1.4%) was characterized as a BC mosaic (B(PR)C(RT)U(gp120)C(gp41)) and an AGH mosaic (AG(PR)G(RT)H(gp120)H(gp41)) was first observed in the country. Antiretroviral resistance to nucleoside RT inhibitor was observed in one sample (1.35%) showing M41L and T215S mutations. Nonnucleoside RT inhibitor and major PR inhibitor resistance mutations were not observed. Previously unseen patterns of resistance to T20 were found among HIV-1-infected drug-naïve individuals in Brazil. Recent infections were characterized in 21.6 percent of the blood donor samples included in this study.
  
  
  CONCLUSIONS
  The availability of characterized plasma samples and HIV isolates will allow the development of biologic reagents necessary to implement quality control programs and to develop, validate, and evaluate the performance of diagnostic kits, considering all HIV-1-circulating variants in the country.
authors.affiliation: Section of Molecular Diagnostics, Diagnostic Technology Laboratory, Bio-Manguinhos, Rio de Janeiro, Brazil.
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Sá-Ferreira
authors.forename: Patrícia Alvarez
authors.initials: PA
authors.lastname: Brindeiro
authors.forename: Saada
authors.initials: S
authors.lastname: Chequer-Fernandez
authors.forename: Amilcar
authors.initials: A
authors.lastname: Tanuri
authors.forename: Mariza Gonçalves
authors.initials: MG
authors.lastname: Morgado
mesh_terms: D044966:Anti-Retroviral Agents / Q000494:pharmacology*; D001782:Blood Donors; D001938:Brazil; D004279:DNA, Viral; D024882:Drug Resistance, Viral / Q000235:genetics; D015497:HIV-1 / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D009154:Mutation; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology
chemical_list: D044966:Anti-Retroviral Agents; D004279:DNA, Viral; D018894:Reverse Transcriptase Inhibitors