Phylogenetic trees for Ontario RSV-A nucleotide sequences from (a) the second variable region of the G gene and (b) partial F gene sequences.

<p>Reference strains representing known genotypes are indicated in bold. Isolates of ON1 genotype circulating in Ontario are indicated by a solid square. Isolates belong to genotype GA5 are marked by an open square. Multiple sequences alignment and phylogenetic trees were constructed using Clustal W and neighbour-joining algorithm running within MEGA 5.05 software. Tree topology was supported by bootstrap analysis with 1000 pseudo replicate datasets. Bootstrap values greater than 50 are shown at the branch nodes. The tree was visualized using Dendroscope software, version 2.2.1.17. The scale bar represents the number of nucleotide substitutions per site between close relatives.