Molecular epidemiology of the attachment glycoprotein (G) gene in respiratory syncytial virus in children with acute respiratory infection in Japan in 2009/2010

This study performed a detailed genetic analysis of the glycoprotein (G) gene of respiratory syncytial virus (RSV) detected in 50 Japanese children with acute respiratory infection (ARI) in the 2009/2010 season. A phylogenetic tree constructed by the neighbour-joining method showed that 34 and 16 of the RSV strains could be classified into subgroups A and B, respectively. Strains belonging to subgroups A and B were further subdivided into GA2 and BA, respectively. The nucleotide and deduced amino acid sequence identities were relatively high among these strains (>90 %). The deduced amino acid sequences implied that a relatively high frequency of amino acid substitutions occurred in the C-terminal 3rd hypervariable region of the G protein in these strains. In addition, some positively selected sites were estimated. The results suggest that RSV with genotypes GA2 and BA was associated with ARI in Japanese children in 2009/2010.