Prevalence and clinical impacts of HIV-1 intersubtype recombinants in Uganda revealed by near-full-genome population and deep sequencing approaches
HIV-1 subtypes A1 and D cocirculate in a rural community in Mbarara, Uganda. This study examines HIV-1 intersubtype recombination in this community under a full-genome sequencing context. We aim to estimate prevalence, examine time trends, and test for clinical correlates and outcomes associated with intersubtype recombinants.Methods:
Near-full-genome HIV-1 Sanger sequence data were collected from plasma samples of 504 treatment-naïve individuals, who then received protease inhibitor or nonnucleoside reverse transcriptase inhibitor-containing regimens and were monitored for up to 7.5 years. Subtypes were inferred by Los Alamos Recombinant Identification Program (RIP) 3.0 and compared with Sanger/REGA and MiSeq/RIP. ‘Nonrecombinants’ and ‘recombinants’ infections were compared in terms of pretherapy viral load, CD4+ cell count, posttherapy time to virologic suppression, virologic rebound, first CD4+ rise above baseline and sustained CD4+ recovery.Results:
Prevalence of intersubtype recombinants varied depending on the genomic region examined: gag (15%), prrt (11%), int (8%), vif (10%), vpr (2%), vpu (9%), GP120 (8%), GP41 (18%), and nef (4%). Of the 200 patients with near-full-genome data, prevalence of intersubtype recombination was 46%; the most frequently observed recombinant was A1-D (25%). Sanger/REGA and MiSeq/RIP yielded generally consistent results. Phylogenetic tree revealed most recombinants did not share common ancestors. No temporal trend was observed (all P > 0.1). Subsequent subtype switches were detected in 27 of 143 (19%) study participants with follow-up sequences. Nonrecombinant versus recombinants infections were not significantly different in any pre nor posttherapy clinical correlates examined (all P > 0.2).Conclusion:
Intersubtype recombination was highly prevalent (46%) in Uganda if the entire HIV genome was considered, but was neither associated with clinical correlates nor therapy outcomes.