High frequency of the GWG (Pro trp) envelope variant of HIV-1 in southeast Brazil

The HIV-1 variant that contains the GWG amino acid sequence in the crown of the principal neutralizing determinant (PND) has been detected in a few patients in Japan, France, and Brazil by direct sequencing. We describe for the first time the use of restriction fragment length polymorphism (RFLP) and limited DNA sequencing of the C2-V3 region of the HN-I envelope (env) gene to determine the prevalence of the variant in 75 HIV-l-infected Brazilian patients. Overall prevalence of the GWC sequence as indicated by RFLP was 57% (43 of 75). The prevalence in females (72%) was higher than that in males (32%) and newborns (40%). Two GFG sequences and I CLG sequence were also detected. This finding is relevant for the planning of vaccines and for studies of the epidemiology of HN-I in Brazil.