Confirmation of putative HIV-1 group P in Cameroon

Abstract

We report the second human immunodeficiency virus (HIV) belonging to the new HIV type 1 (HIV-1) group P lineage that is closely related to the simian immunodeficiency virus found in gorillas. This virus was identified in an HIV-seropositive male hospital patient in Cameroon, confirming that the group P virus is circulating in humans. Results from screening 1,736 HIV-seropositive specimens collected in Cameroon indicate that HIV-1 group P infections are rare, accounting for only 0.06% of HIV infections. Despite its rarity, group P shows evidence of adaptation to humans.

FIG. 1.

PCR amplification of the 06CMU14788 genome. First-round-PCR products are shown as dotted lines, and nested-PCR products are shown as solid lines. The nested products are labeled A to I, with numbers indicating the 5′- and 3′-nucleotide positions within the assembled 06CMU14788 genome sequence.

FIG. 2.

Phylogenetic tree derived from nucleotide alignment of genome sequences. HIV-1 group M is represented by single sequences for each subtype A through H; group N and group O are each represented by 5 sequences, with isolates YBF30, ANT70, and MVP5180 indicated, and SIVgor is represented by 3 sequences, CP684, CP2135, and CP2139. The alignment consisted of 7,509 nucleotides after gaps were stripped. Reproducibilities of key nodes are shown as percentages.

FIG. 3.

Similarity plot of nucleotide genome alignment using 06CMU14788 as the query sequence. The alignment consisted of 8,218 nucleotides (nt) after gaps were stripped and was evaluated using a window of 500 nucleotides and a step of 50 nucleotides. The thick black line represents group P isolate RBF168, and the thick dark-gray line represents SIVgor CP2139. The thinner gray lines represent group O ANT70 (medium gray), group N YBF30 (light gray), and group M HXB2 (pale gray).