Send to:

Choose Destination
See comment in PubMed Commons below
AIDS. 2003 Jan 3;17(1):11-21.

A specific subtype C of human immunodeficiency virus type 1 circulates in Brazil.

Author information

  • 1Laboratório de Virologia Molecular, Departamento de Genética, Universidade Federal do Rio de Janeiro, CCS - Bloco A - Cidade Universitária - Ilha do Fundão, 21944-970 Rio de Janeiro, RJ, Brazil.



To characterize the subtype C strains of HIV type 1 that circulate in Brazil, especially those originated from the southern part of the country.


One hundred and twelve HIV-1-positive subjects had their plasma viral RNA extracted. Protease (PR) and reverse transcriptase (RT) genomic regions were polymerase chain reaction-amplified and sequenced for subtype determination. Subtype C strains were selected and compared to other strains of this subtype from the database, and specific amino acid signature patterns were searched.


Brazilian subtype C viruses form a very strong monophyletic group when compared to subtype C viruses from other countries and presented specific signature amino acids. Recombinants between subtype C and B viruses have been documented in areas of co-circulation. The incidence of primary PR and RT inhibitor resistance mutations in drug-naïve subjects was observed. An increasing number of secondary resistance mutations was also seen, some of which are characteristic of subtype C-related sequences.


Introduction of subtype C of HIV-1 in Brazil was likely a single event of one or a mixture of similarly related strains. Recombination between subtype C and B viruses is an ongoing process in the country. Primary and secondary drug resistance mutations were observed, although some of the secondary mutations could be associated with subtype C molecular signatures. Subtype-specific polymorphisms of PR and RT sequences found in this subtype C Brazilian variant might influence this emergence and have an impact on HIV treatment and on vaccine development in the country.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Lippincott Williams & Wilkins
    Loading ...
    Write to the Help Desk