Long-term culture of human immunodeficiency virus type 1 resulting in lossof glycosylation sites

Cultures of human immunodeficiency virus type 1 (HIV-1) provided a model fo r the study of mutations in the absence of host antibodies. Replicate cultu res of biological and molecular clones of HIV-1 were passaged weekly for 30 or 34 weeks. Eight regions of HIV-1 genomic RNA were analyzed by means of single-strand conformation polymorphism analysis and nucleotide sequencing. Six mutations were detected in the biological clones. Two were G-->A subst itutions. The frequency of mutations was higher in V1 compared to that in o ther regions (P=0.01). Three mutations involved loss of potential glycosyla tion sites in V1. These results show that mutations in the viral genome may result from selection by factors other than host immune pressures. J, Med. Virol. 63:197-202, 2001, (C) 2001 Wiley-Liss, Inc.