Fig. 1

Phylogenetic analysis of gag-protease sequences from West Africa. Maximum-likelihood phylogenetic trees of gag-protease sequences a and subtype distribution b from West Africa. Phylogenetic trees were constructed using the PhyML tool on the LANL HIV database. Subtypes and inter-subtype recombinants were confirmed using reference sequences downloaded from the LANL HIV database. Branches representing subtype reference sequences are labeled in black