Characterization of envelope sequence of HIV virus in children infected with HIV in Vietnam.

ABSTRACT

BACKGROUND: HIV is characterized by high levels of genetic variability, including increased numbers of heterogeneous sequences of the envelope region. Therefore, studying genetic variability of HIV in relation to viral replication might facilitate prognosis of disease progression. METHODS: The study was designed as cross-sectional; data and samples of participants collected and analyzed env genes were obtained from 23 children enrolled by Vietnam National Children's Hospital. RESULTS: Substantial mutations in the C2 region were found in patients with high levels of viral replication while changes in the C3 region were mostly found in patients with low viral load. In the V1 region, we found profound amino acid modifications in patients with low HIV viral loads in contrast to the V2 sequence, where we identified single point mutations in patients with increased HIV viral load. The V3 region was relatively homogeneous, while profound deletions in the V4 region were detected in patients with increased viral replication. CONCLUSION: Our results suggest that genetic variations in different regions of the HIV envelope sequence, including both conserved C2 and C3 and variable V1/V2 and V4 regions, might be involved in increased viral infectivity and replication capacity. Such knowledge might help improve prediction of HIV progress and treatment in patients.