Phylogenetic analysis of HIV-1 sequences.

<p><b>a)</b> Maximum likelihood tree inferred from the 190 concatenated group O sequences, with white diamonds at nodes with bootstrap values >70 and colours highlighting the nature of the residue at position 181 in the Reverse Transcriptase: Pink = C (N = 116); Green = Y (N = 71); Blue = mixed Y and C (N = 3); Grey = sequences from patients non NNRTI-naïve or with no data about NNRTI treatment. <b>b)</b> Maximum likelihood tree inferred from the 190 concatenated group M sequences.