Inter- and Intra-Host Evolution of Dengue Viruses and the Inference to the Pathogenesis

Dengue viruses, like many RNA viruses are highly mutagenic, which have a potential to generate approximately one nucleotide mutation per round of genome replication (Domingo, Escarmis et al. 1996). The extent of genetic diversity differs among the sylvatic/urban cycles, chronologically isolates, serotypes and genotypes of Dengue viruses. All four serotypes of Dengue viruses (DENV-1 to DENV-4) evolved independently in their particular ecologic niche and could further classified into different genotypes among each serotypes based on nucleotide homology. Currently DENV-1 is classified into five different genotypes, DENV-2 into six different genotypes, DENV-3 into five different genotypes and DENV-4 into four different genotypes (Holmes and Twiddy 2003; Klungthong, Zhang et al. 2004; King, Chao et al. 2008; Vasilakis and Weaver 2008).