Positive selection and evolution of dengue type-3 virus in the Indian subcontinent

Abstract

Positive selection in the codon corresponding to R86 of the highly conserved surface C-protein is important in view of its occurrence in a T-cell epitope as well as its strict conservation in all the DEN strains. Phylogenetic analysis of the C-prM junction sequences showed that three strains of 2006 are rapidly evolving. These results were also supported by calculations of the substitution rates. Their significance in the expansion of viral epidemics requires to be investigated.