Evolution of Type B Influenza Virus Using a Mass Spectrometry Based Phylonumerics Approach

A mass spectrometry based phylonumerics approach has been applied to study the molecular evolution of influenza hemagglutinin of type B strains of the Victoria and Yamagata lineage. The results demonstrate that, despite the similar evolutionary topologies, the mutation profiles and diversity associated with the evolution of each lineage is very different. Most mutations occur exclusively in one lineage versus the other, and the mutation locations are largely difference. Despite this, the evolutionary dynamics share features with each other and type A hemagglutinin in that a large number of mutations in both lineages occur within known antigenic loop domains, where consecutive potential epistatic mutations occur in different loop regions, or successively within and outside such a region. The results are largely in accord with other conventional phylogenetic studies of the evolution and antigenic dynamics of such strains thus further validating the method.