Identification of new HIV-1 circulating recombinant forms CRF81_cpx and CRF99_BF1 in central western Brazil and of unique BF1 recombinant forms
Nenhuma Miniatura disponível
Data
2019
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
Intersubtype recombinants classified as circulating recombinant forms (CRFs) or unique
recombinant forms (URFs) have been shown to play an important role in the complex
and dynamic Brazilian HIV/AIDS epidemic. Previous pol region studies (2003–2013) in
828 patients from six states from Central Western, Northern and Northeastern Brazil
reported variable rates of BF1, F1CB, BC, and CF1 mosaics. In this study HIV-1 subtype
diversity BF1, F1CB, BC, and CF1 recombinants in pol were analyzed. Full/nearfull/partial genome sequences were generated from F1CB and BF1 recombinants.
Genomic DNA extracted from whole blood was used in nested-PCR to amplify
four overlapping fragments encompassing the full HIV-1 genome. Phylogenetic trees
were generated using the neighbor-joining/NJ method (MEGA 6.0). The time of the
most recent common ancestor (TMRCA) of F1CB and BF1 clades was estimated
using a Bayesian Markov Chain Monte Carlo approach (BEAST v1.8; BEAGLE).
Bootscanning was used for recombination analyses (Simplot v3.5.1); separate NJ
phylogenetic analysis of fragments confirmed subtypes. The phylogenetic analyses of
protease/reverse-transcriptase sequences in 828 patients revealed 76% subtype B
(n = 629), 6.4% subtype C (n = 53), 4.2% subtype F1 (n = 35), 13.4% intersubtype
recombinants: 10.5% BF1 (n = 87), 2.3% BC (n = 19), 0.4% F1CB (n = 3), and 0.2%
CF1 (n = 2). Two full and one partial BF1C genomes allowed the characterization of
the CRF81_cpx that has 9 breakpoints dividing the genome into 10 subregions. Basic
Local Alignment Search Tool searches (Los Alamos HIV Sequence Database) identified
six other sequences with the same recombination profile in pol, five from Brazil, and
one from Italy. The estimated median TMRCA of CRF81_cpx was 1999 (1992–2003).
CRF60_BC-like sequences, originally described in Italy, were also found. Two full and
one near full-length BF1 genomes led to the characterization of the new CRF99_BF1
that has six recombination breakpoints dividing the genome into seven subregions.
Two new URFs BF1, with six recombination breakpoints and seven subregions were also characterized. The description of the first Brazilian BF1C CRF81_cpx and of the
new CRF99_BF1 corroborate the important role of CRFs in the HIV/AIDS epidemic
throughout Brazil. Our data also highlight the value of HIV-1 full-genome sequence
studies in order to fully reveal the complexity of the epidemic in a huge country as
Brazil.
Descrição
Palavras-chave
HIV-1, CRFs, URFs, Molecular epidemiology, Central western, Brazil
Citação
REIS, Mônica N. G. et al. Identification of new HIV-1 circulating recombinant forms CRF81_cpx and CRF99_BF1 in central western Brazil and of unique BF1 recombinant forms. Frontiers in Microbiology, Lausanne, v. 10, e97, 2019. DOI: 10.3389/fmicb.2019.00097. Disponível em: https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.00097/full. Acesso em: 11 fev. 2025.