Genetic Analyses of HIV-1 Strains Transmitted from Mother to Child in Northern Vietnam

Abstract

We previously reported mother-to-child transmission of HIV-1 in nine (6.7%) of 135 children on nevirapine prophylaxis in Vietnam. In the current study, we investigated the appearance and profile of antiretroviral drug (ARV) resistance mutations, the predicted coreceptor usage, and the genetic diversity of HIV-1 strains isolated from the eight pairs of HIV-1-infected mothers and their children, who were followed up to 12 months after birth. Portions of the pol and env C2V3 regions of the HIV-1 strains were analyzed genetically. HIV-1 CRF01_AE RNA was detected in four (50%) children at delivery. Y181C, a nevirapine resistance mutation, appeared in two (25%) children 1 and 3 months after birth, respectively. No ARV resistance mutation was detected in the mothers, though three mothers were on ARV prophylaxis. Five mothers and their children harbored CCR5-tropic (R5) viruses. Two mothers harbored both R5 and CXCR4-tropic (X4) viruses, but their children harbored only R5 viruses even though the X4 viruses were dominant in the mothers. In the remaining one mother, HIV-1 RNA was not amplified and her child harbored both R5 and X4 viruses at birth, but only X4 virus 12 months after delivery. The infants' viruses were more homogeneous than their mothers' viruses (mean distance: 0.5% vs.

Molecular linkage tracing of HIV-1 transmission events in seroconcordant couples in Guangxi Province, Southeastern China

“…The fragment spanning the HIV-1 pol gene region (1.2 kb nucleotides in length), encoding all 99 amino acids in HIV protease and the first 317 amino acids in HIV reverse transcriptase, was amplified by one-step reverse transcription polymerase chain reaction (RT-PCR) (Phan et al 2015). Considering the relatively high diversity of the envelope region, C2V5 sequences (HXB2 coordinates: 7002–7663) were amplified using near-limiting-dilution PCR.…”