Abstract

PIP: Findings are reported from a study conducted to fully sequence the gp120 gene from a Brazilian HIV-1 isolate containing the GWGR motif and compare it to the Brazilian B and F sequences already described. Genomic DNA isolated from six patients in an ongoing HIV cohort study was screened for the presence of the viral V3 loop GWGR motif. Sequence analysis revealed that BZ(GWGR)1 is closely related to the North American MN prototype strain, with 80.1% amino acid identity and 89.1% nucleic acid similarity, and with 6 deletions and 11 insertions. Large differences were, however, observed when the V1 and V2 regions of MN and BZ(GWGR)1 were compared. Tree analysis based upon amino acid sequences and the four Brazilian isolates introduced in the analysis indicate that BZ(GWGR)1 belongs to the HIV-1 B subtypes. Several features of BZ(GWGR)1 suggest that some biological advantage may be derived from the differences between that variant and the American/European prototype strain.