| timing the ancestor of the hiv-1 pandemic strains. | hiv-1 sequences were analyzed to estimate the timing of the ancestral sequence of the main group of hiv-1, the strains responsible for the aids pandemic. using parallel supercomputers and assuming a constant rate of evolution, we applied maximum-likelihood phylogenetic methods to unprecedented amounts of data for this calculation. we validated our approach by correctly estimating the timing of two historically documented points. using a comprehensive full-length envelope sequence alignment, we e ... | 2000 | 10846155 |