HIV type 1 genetic variability in central Brazil

Area of Science:

• Virology
• Genetics
• Epidemiology

Background:

• Understanding the genetic diversity of Human Immunodeficiency Virus type 1 (HIV-1) is crucial for effective treatment and vaccine development.
• Previous studies have indicated significant HIV-1 subtype diversity across Brazil.

Purpose of the Study:

• To analyze the genetic variability of HIV-1 pol and env genes in Central Brazil.
• To determine the prevalence of different HIV-1 subtypes and identify recombinant forms.
• To investigate the antigenic diversity of the gp120 V3 loop.

Main Methods:

• Nested PCR amplification and sequencing of HIV-1 protease, reverse transcriptase, and C2C3/env genes.
• Subtyping using the REGA program and phylogenetic analyses.
• Recombinant form analysis using SimPlot software.
• Amino acid sequence analysis of the gp120 V3 loop.

Main Results:

• A high prevalence of HIV-1 subtype B (95.1%) was observed in Central Brazil, with a small proportion of mosaic B/F viruses (4.9%).
• The most common gp120 V3 loop motif was GPGR (43.3%), prevalent in subtypes B and F, followed by GPGK (10%).
• Phylogenetic analysis indicated that Central Brazil subtype B strains cluster polyphyletically, showing similarity to strains from other regions.

Conclusions:

• Subtype B is the predominant HIV-1 strain in Central Brazil, with genetic similarities to strains found globally.
• The identified genetic diversity, particularly in the V3 loop, provides valuable data for HIV-1 research and vaccine strategies in the region.