High genetic diversity of human immunodeficiency virus type 1 in Angola

To investigate which HIV-1 genetic forms are circulating in Angola, we have determined the gag and/or env genotypes of 48 isolates from patients living in Cabinda and Luanda provinces. The following subtypes were identified: A ₁ (18 samples, 38%), C (7, 15%), H (5, 10%), J (3, 6%), G (2, 4%), A₂ (2, 4%), F₁ (1, 2%), and D (1, 2%). The env gene fragment was untypable in one sample. Discordant subtype classifications in the gag and env genes were found in eight (17%) samples. There were six different recombination patterns (gag/env): A₁/H (3, 6%), A₁/G (1, 2%), C/A₂ (1, 2%), F1/B (1, 2%), G/B (1, 2%), and G/H (1, 2%). The A₁/H recombinant may represent a new circulating recombinant form. The marked genetic heterogeneity of HIV-1 in Angola has important implications for vaccine development.