Trends of HIV1 molecular epidemiology in Venezuela: introduction of subtype C and identification of a novel B/C mosaic genome (original) (raw)
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Techniques used to identify the Brazilian variant of HIV-1 subtype B
Brazilian Journal of Medical and Biological Research, 2007
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Aids Research and Human Retroviruses, 2009
The aim of this study was the analysis of human immunodeficiency virus (HIV) diversity in Venezuela, and the characterization of variants other than subtype B. A total of 425 HIV isolates, collected between 2003 and 2008, were analyzed. The sequence of at least one genomic region (Pol, Env, Vif, or Nef ) was available for all of them and at least two genomic regions were analyzed in 46% of them. From the 425 HIV isolates analyzed, 421 (99.1%) were classified as HIV-1 subtype B. The four non-subtype B isolates correspond to one subtype C, one recombinant AG, and two HIV-2 isolates. This study shows that HIV-1 subtype B is still highly predominant in Venezuela. Whereas some sporadic cases of other HIV types can be found, they do not seem to have disseminated to the present.
AIDS Research and Human Retroviruses, 2000
ABSTRACT Eight HIV-1 isolates from Venezuela have been characterized by nucleotide sequencing of the entire reverse transcriptase (RT)- and surface glycoprotein (gp 120)-coding regions. Average mutant frequencies were 2.5 x 10(-2) substitutions per nucleotide (s/nt) for the RT-coding region, and 10 x 10(-2) or 6.8 x 10(-2) s/nt for the gp120-coding region, depending on whether gaps introduced for optimal alignment were or were not, respectively, considered in the calculations. Phylogenetic trees were derived by maximum-likelihood, neighbor-joining, and maximum parsimony methods. In the trees derived from both RT- and gp120-coding regions, Venezuelan isolates cluster with subtype B viruses. However, the relative position of some of the isolates is considerably different in the two trees. Unique V3 loop amino acid sequences, not represented in the current database, have been identified among the Venezuelan isolates. In addition to representing the first molecular characterization of HIV-1 from Venezuela, the extensive genetic heterogeneity observed reinforces the interest in characterizing additional HIV-1 isolates worldwide for adequate vaccine design.
AIDS Research and Human Retroviruses, 1996
Human immunodeficiency virus type 1 sequences have been shown to cluster into two distinct groups, called M (main) and O (outlier).1 Group M sequences, to which the majority of published HIV-1 sequences belong, have been further subdivided into eight genetic subtypes named A through H,1 and additional subtypes have been proposed (I and J).2-3 Subtype B dominates on the American continent and has been reported from the United States, Venezuela, Brazil, and Paraguay. However, in Brazil, subtype B coexists with subtypes C and F.4 A previous study performed in 1992 reported Argentine V3 loop sequences and although subtype characterization was not performed at that time the amino acid patterns resembled those of subtype B.5 Subtypes B and F have been reported from Rosario City in northeastern Argentina.6 Blood samples from four unrelated patients in Buenos Aires, Argentina, were collected in 1993. Two of the virus popula-10.
The Molecular Epidemiology of HIV Type 1 of Men in Mexico
AIDS Research and Human Retroviruses, 2001
Genotypic characteristics of human immunodeficiency virus type 1 (HIV-1) in Mexico were investigated in a multicenter study that involved centers in five geographic regions of the country. Study samples (n 5 65) collected from male patients in 1998-1999 were sequenced within the C2-V5 region of the gp120 env gene. Phylogenetic analysis revealed that subtype B predominates in Mexico. The level of interpatient nucleotide diversity (mean value of 8.9%) was congruent with multiple introductions of the virus and the "aging" epidemic in Mexico. One-third of samples (30.8% of cases) showed polymorphism within the crown of the V3 loop demonstrating non-GPGR motifs. Two new motifs in the V3 loop crown-HPGG and GPEG-were observed. The evolution of the AIDS epidemic in Mexico should be closely monitored since non-B HIV-1 subtypes might be introduced. The nucleotide sequences were deposited in the GenBank under accession numbers AF200855-AF200869, AF200871-AF200892, and AF200894-AF200921.
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To study the molecular epidemiology of human immunodeficiency virus type 1 (HIV-1) strains in Medellín, Colombia, 115 HIV-1-positive individuals who were recruited from an HIV outpatient hospital (Universitario San Vicente de Paul) during the period from July 2001 to January 2002 were genotyped. All samples were analyzed by envelope heteroduplex mobility assay and found to be subtype B. Twenty-four samples were randomly selected for sequencing of the protease and the reverse transcriptase regions; all isolates were found to be subtype B. Phylogenetic analysis of seven nearly full-length genomes showed that all samples were subtype B. This study shows that the HIV epidemic in Colombia continues to be dominated by the subtype B virus. The predominance of subtype B genotypes of HIV-1 strains in Medellín resembles what is seen in the nearby countries of Peru, Ecuador, and Venezuela. Previous molecular surveillance studies have showed sig- nificant heterogeneity in the prevalence and geo...
AIDS Research and Human Retroviruses, 2001
According to the epidemiology of human immunodeficiency virus infection in Cuba, the main sources of infection have been persons coming from foreign countries, mainly from Africa, and individuals who have had sexual contacts with foreigners in Cuba. However, the first Cuban HIV-1 isolates sequenced have been all classified as subtype B. In this note we report the sequence of the gp120 C2/V3 region from 11 HIV-1 isolates from Cuban patients. DNA was isolated either directly from blood PBMC or from primary isolates, PCR amplified and sequenced. Six isolates were classified as subtype B and three of them had the atypical sequences GRGR, GWGR, and TPGR on the tip of the V3 loop. Besides, two other sequences were classified as subtype A, two as subtype H, and one as subtype C. These results confirm that although subtype B seems to be predominant, HIV-1 isolates from various subtypes do circulate in Cuba.