Evolutionary Modeling of Rate Shifts Reveals Specificity Determinants in HIV-1 Subtypes Penn, Osnat ; Stern, Adi ; Rubinstein, Nimrod D. ; Dutheil, Julien ; Bacharach, Eran ; Galtier, Nicolas ; Pupko, Tal Abstract Publication: PLoS Computational Biology Pub Date: November 2008 DOI: 10.1371/journal.pcbi.1000214 Bibcode: 2008PLSCB...4E0214P