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Updated: May 9, 2026
14:23
A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses
Published on: August 31, 2014
HIV type 1 polymerase gene polymorphisms are associated with phenotypic differences in replication capacity and
Oon Tek Ng1, Oliver Laeyendecker, Andrew D Redd
1Department of Medicine.
The Journal of Infectious Diseases
|August 8, 2013
Summary
Human immunodeficiency virus type 1 (HIV-1) subtype D pol infection, especially with high replication capacity, accelerates disease progression. Genetic variations in the pol gene influence this progression and viral replication capacity.
Area of Science:
- Virology
- Immunology
- Epidemiology
Background:
- The factors influencing the varying rates of clinical disease progression in individuals infected with human immunodeficiency virus type 1 (HIV-1) subtypes are not well understood.
- Understanding these determinants is crucial for predicting disease trajectory and developing targeted interventions.
Purpose of the Study:
- To investigate the association between HIV-1 subtypes, specifically the pol gene, and the rate of clinical disease progression.
- To examine the role of viral replication capacity (RC) and amino acid polymorphisms within the pol gene in influencing disease progression.
Main Methods:
- HIV-1 subtypes were determined across five genomic regions in 396 Ugandan seroconverters using a multiregion hybridization assay.
- Replication capacities (RC) of HIV-1 pol genes were measured in a subset of 145 individuals.
- Statistical analyses were performed to associate genomic regions, pol RC, and amino acid polymorphisms with disease progression endpoints.
Main Results:
- HIV-1 subtype D pol infection was associated with a 2.4-fold increased hazard of disease progression compared to subtype A.
- High pol RC (>67%) in subtype D infections significantly increased the hazard of progression (HR, 4.6), while lower RC did not show a significant difference.
- Specific amino acid substitutions in the protease and reverse transcriptase regions of the pol gene correlated with significant variations in pol RC.
Conclusions:
- Differences in HIV-1 pol gene subtypes and their replication capacities are linked to variations in disease progression rates.
- Amino acid polymorphisms within the pol gene may play a role in modulating viral replication capacity and, consequently, disease progression.
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