Recombinant human immunodeficiency viruses type 1 circulating in Spain

Area of Science:

• Virology
• Molecular Biology
• Epidemiology

Background:

• Human Immunodeficiency Virus type 1 (HIV-1) genetic diversity is a significant public health concern.
• Understanding the genetic makeup of HIV-1 strains is crucial for effective treatment and prevention strategies.
• Immigrant populations can introduce and facilitate the spread of diverse or recombinant HIV-1 strains.

Purpose of the Study:

• To perform phylogenetic characterization of HIV-1 clinical isolates from immigrants in Spain.
• To identify and analyze recombinant HIV-1 strains within this population.
• To understand the genetic diversity and subtype distribution of HIV-1 in Spain.

Main Methods:

• Phylogenetic analyses of protease, reverse transcriptase (RT), and envelope (env) genes.
• Comparison of HIV-1 sequences from 13 immigrant isolates against a reference panel of 25 sequences representing various subtypes.
• Identification of discrepant topologies indicating genetic recombination.

Main Results:

• Discrepant phylogenetic topologies were found in 10 out of 13 HIV-1 isolates, indicating genetic recombination.
• Eight strains showed discrepant env genes compared to concordant pol genes.
• Multiple HIV-1 subtypes (A, B, C, D, G, H) were identified within single isolates, including recombinant strains like H/A, H/B, and a triple recombinant A/D/C variant.

Conclusions:

• This study provides the first phylogenetic characterization of HIV-1 recombinant clinical isolates in Spain.
• The findings highlight the presence of complex HIV-1 genetic recombinants among immigrants in Spain.
• Genetic diversity and recombination underscore the need for ongoing surveillance of HIV-1 strains.