Ormation were obtained. RNA was extracted from plasma samples, reverse transcribed and PCR amplified as described previously [12] using subtype non-specific HIV-1 primers for HIV-1 full length gag [12] and nef [13] genes, and sequenced. Sequenced fragments were assembled using ChromasPro. Full length gag and nef sequences were generated and aligned using MUSCLE with manual editing in MEGA5, togeth