Analysis of near full-length genome sequences of HIV type 1 BF intersubtype recombinant viruses from Brazil reveals their independent origins and their lack of relationship to CRF12_BF.

Area de Patogenia Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III. Ctra. Majadahonda-Pozuelo, Km. 2. 28220 Majadahonda (Madrid), Spain.
AIDS Research and Human Retroviruses (Impact Factor: 2.46). 11/2004; 20(10):1126-33. DOI: 10.1089/aid.2004.20.1126
Source: PubMed

ABSTRACT We analyze the recombinant structures and phylogenetic relationships of nine near full-length genome sequences of HIV-1 BF intersubtype recombinant viruses from Brazil, eight of them newly derived. These were obtained by PCR amplification from peripheral blood mononuclear cells (PBMCs) DNA or PBMCs culture supernantant RNA. The recombinants exhibited unique mosaic structures, except two viruses with a single near coincident breakpoint. Comparison with CRF12_BF revealed only two coincident breakpoints in two recombinants. Phylogenetic analyses failed to support a common ancestry of Brazilian recombinants or their relationship to CRF12_BF, which widely circulates in Argentina. Intersubtype breakpoint distribution along the genome was uneven, with the highest mean frequency in the polymerase domain of reverse transcriptase, and the lowest in env. These results indicate that HIV-1 BF recombinants from Brazil have independent origins and are unrelated to CRF12_BF, and that intersubtype breakpoints are frequent in pol segments analyzed for drug resistance detection.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We report the identification of a novel HIV-1 circulating recombinant form (CRF72_BF1) in deep sequencing data from peripheral blood mononuclear cells (PBMC) of five blood donors in southeastern Brazil. Detection of this circulating recombinant form (CRF) confirms the need for effective surveillance to monitor the prevalence and distribution of HIV variants in a variety of settings in Brazil.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: One of the major characteristics of HIV-1 is its high genetic variability and extensive heterogeneity. This characteristic is due to its molecular traits, which in turn allows it to vary, recombine, and diversify at a high frequency. As such, it generates complex molecular forms, termed recombinants, which evade the human immune system and so survive. There is no sequence constraint to the recombination pattern as it appears to occur at inter-group (between groups M and O), as well as interand intra-subtype within group M. Rapid emergence and active global transmission of HIV-1 recombinants, known as circulating recombinant forms (CRFs) and unique recombinant forms (URFs), requires urgent attention. To date, 55 CRFs have been reported around the world. The first CRF01_AE originated from Central Africa but spread widely in Asia. The most recent CRF; CRF55_01B is a recombinant form of CRF01_AE and subtype B, although its origin is yet to be publicly disclosed. HIV-1 recombination is an ongoing event and plays an indispensable role in HIV epidemics in different regions. Africa, Asia and South America are identified as recombination hot-spots. They are affected by continual emergence and cocirculation of newly emerging CRFs and URFs, which are now responsible for almost 20% of HIV-1 infections worldwide. Better understanding of recombinants is necessary to determine their biological and molecular attributes.
    Infectious disease reports 06/2013; 5(Suppl 1):e4. DOI:10.4081/idr.2013.s1.e4
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: The findings of frequent circulation of HIV-1 subclade F1 viruses and the scarcity of BF1 recombinant viruses based on pol subgenomic fragment sequencing among blood donors in Pernambuco (PE), Northeast of Brazil, were reported recently. Here, we aimed to determine whether the classification of these strains (n = 26) extends to the whole genome sequences. Methods: Five overlapping amplicons spanning the HIV near full-length genomes (NFLGs) were PCR amplified from peripheral blood mononuclear cells (PBMCs) of 26 blood donors. The amplicons were molecularly bar-coded, pooled, and sequenced by Illumina paired-end protocol. The prevalence of viral variants containing drug resistant mutations (DRMs) was compared between plasma and PBMCs. Results: Of the 26 samples studied, 20 NFLGs and 4 partial fragments were de novo assembled into contiguous sequences and successfully subtyped. Two distinct BF1 recombinant profiles designated CRF70_BF1 and CRF71_BF1, with 4 samples in profile I and 11 in profile II were detected and thus constitute two novel recombinant forms circulating in PE. Evidence of dual infections was detected in four patients co-infected with distinct HIV-1 subtypes. According to our estimate, the new CRF71_BF1 accounts for 10% of the HIV-1 circulating strains among blood donors in PE. Discordant data between the plasma and PBMCs-virus were found in 15 of 24 donors. Six of these strains displayed major DRMs only in PBMCs and four of which had detectable DRMs changes at prevalence between 1-20% of the sequenced population. Conclusions: The high percentage of the new RF71_BF1 and other BF1 recombinants found among blood donors in Pernambuco, coupled with high rates of transmitted DRMs and dual infections confirm the need for effective surveillance to monitor the prevalence and distribution of HIV variants in a variety of settings in Brazil.
    PLoS ONE 11/2014; 9(11):e112674. DOI:10.1371/journal.pone.0112674 · 3.53 Impact Factor