Single-Nucleotide Polymorphism Landscape and Allele Frequency Patterns in the HIV-1 Envelope (env) Gene

Abstract

The Human Immunodeficiency Virus (HIV) envelope glycoprotein (Env) is pivotal in mediating viral entry into host cells and serves as a key target for vaccine development. The HIV-1 envelope (env) gene exhibits extensive genetic variability, driven largely by the accumulation of single-nucleotide polymorphisms (SNPs) that arise during viral replication and evolution. This study aims to dissect the genetic intricacies of the HIV Env gene by analyzing SNP distribution and allelic frequency patterns.Using sequences retrieved from the NCBI database, we conducted a comprehensive analysis utilizing the R statistical environment. We assessed SNP distribution across codon positions and evaluated allelic frequencies within various HIV populations. Our results indicate non-uniform SNP distributions with a high density at the third codon position, suggesting potential hotspots for mutational activity. The allelic frequency patterns displayed multimodal distributions, indicating a substantial proportion of multimodal allele frequency spectra across polymorphic sites, reflecting variable mutation persistence across viral sequences. These findings highlight a pronounced peak in allele frequencies around 0.6, suggesting selective advantages for certain alleles. The majority of loci were biallelic, revealing significant genetic diversity, which is crucial for the virus's adaptability. Our study underscores the complex nature of HIV genetic variation and its implications for the virus's evolution, the development of vaccines, and therapeutic strategies. The insights gained from this research contribute to the understanding of HIV's adaptive mechanisms and pave the way for personalized medical approaches in HIV treatment.