Phylogenetic relationships based on
gene (1302 nt) of the HIV-1
gene between the HIV-1 non-B pure subtypes circulating in Italy (shown in bold and underlined) and representative strains of HIV-1 M group (subtypes A, C, D, F1, F2, G, H, J, K) from the Los Alamos HIV Sequence Database. The scale bar indicates 5% nucleotide sequence divergence.* indicates the P value < 0.001 (zero length branch test) and the bootstrap values more than 70%.