Sequence variability of the HIV type 1 protease gene in thai patients experienced with antiretroviral therapy.

One hundred sequences of HIV-1 protease with the two flanking cleavage sites from 10 antiretroviral drug-treated Thai patients were examined for residue variability and for mutations at positions associated with the resistance to protease inhibitors. Seven patients were infected with CRF01_AE, two with subtype B, and one with a strain that did not belong to any of the currently identified subtypes or recombinant forms. A total of 46 out of the 99 positions (46%) in HIV-1 protease showed at least one amino acid change as compared with the HXB2 subtype B protease.