In-depth analysis of the origins of HIV type 1 subtype C in South America

AIDS Res Hum Retroviruses. 2009 Oct;25(10):951-9. doi: 10.1089/aid.2008.0293.

Abstract

The South American HIV-1 epidemic is characterized by the co-circulation of subtype B and BF recombinant variants. Together with the B and BF genotypes, HIV-1 subtype C (HIV-1C), F1, and several other recombinants have been reported. The epidemiological significance and immune correlates of these "non-B-non-BF" strains circulating in South America are still uncertain and therefore are increasingly attracting the interest of the scientific community. In this study, the South American HIV-1C epidemic was studied using new technologies for the phylogenetic analysis of large datasets. Our results indicate that there is a major clade encompassing most of the South American HIV-1C strains. These analyses also agreed that some strains do not group inside this major clade, suggesting that there could be HIV-1C sequences of different origins circulating in South America. Others have proposed different hypotheses about the origins of HIV-1C strains from South America. This study shows that an exact single origin cannot be determined, a fact that could be attributed to sampling problems, phylogenetic uncertainty, and the shortage of historical and epidemiological data. Currently, the reported data indicate that HIV-1C strains were introduced in Brazil and afterward spread to other regions of South America. By using character optimization on the obtained phylogenetic trees, we observed that Argentina could also be a point in which the HIV-1C epidemic entered South America.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cluster Analysis
  • HIV Infections / epidemiology*
  • HIV Infections / virology*
  • HIV-1 / classification*
  • HIV-1 / genetics*
  • HIV-1 / isolation & purification
  • Humans
  • Molecular Epidemiology
  • Molecular Sequence Data
  • Phylogeny
  • Sequence Analysis, DNA
  • Sequence Homology
  • South America / epidemiology

Associated data

  • GENBANK/FJ659846
  • GENBANK/FJ659847
  • GENBANK/FJ659848
  • GENBANK/FJ659849