Phylogenetic analysis of HRSV-B GB13 strains designated to the BAIV lineage.

<p>The phylogenetic tree was constructed based on a 762-nucleotide fragment of the G protein, consisting of the two hypervariable regions. The nucleotide sequence of the GB13 designated strains were compared to strains from Buenos Aires (BA) and South Africa (SA) and assigned to branches of GB13. The numbers at the internal nodes represent bootstrap values, determined for 1000 iterations by the neighbour joining method. Only bootstrap values >70 are indicated. The amino acid substitutions that originate the main branches are indicated at the left of the nodes. Based on the presence of a certain amino acid position, several clusters were diversified. The red cluster groups the strains carrying the S267L substitution. The strains of the dark blue cluster share the I281T and T270I substitution. The cluster indicated in green groups the sequences with the L219P substitution. The turquois coloured branch indicates the sequences with the 2292G substitution. Within this cluster, sublineages characterised by the E226D mutation and T289I mutation can be distinguished. Brackets group strains with amino acid substitutions associated with the origin of new sublineages of the GB13 genotype. Strains with termination codon different from Q310STOP are indicated by #. Strains that do not have the H287Y substitution are indicated by single *. Strains indicated with **have the T270I substitution.