Figure 4: Phylogeny of DENV-4 in Puerto Rico and the US Virgin Islands (USVI). A consensus phylogenetic tree (50% majority-rule) was obtained by Bayesian phylogenetic analysis (Mr. Bayes, v. 3.2.) based on the envelope protein gene. Analysis included sequences of strains from USVI (1994) and Puerto Rico (1982–2010) available in the GenBank database, and representative sequences from DENV-4 genotypes I–III and Sylvatic . DENV-1, DENV-2, and DENV-3 were used to root the tree (not shown). Bayesian posterior probability values (>80) are shown for the principal nodes. Taxa are highlighted according to its geographical origin: Puerto Rico (green) and USVI (orange). A red dot identifies sequences obtained from blood donors.