Figure A2. Phylogenetic analysis of norovirus genogroup I nucleotide sequences. The phylogenetic tree was generated by neighbor-joining analysis of the partial nucleotide sequences of the capsid N-terminal/Shell domain with bootstrapping of 1,000 replicates using MEGA version 3.1. Isolates identified in this study are highlighted in boldface. Bootstrap values >80 are shown at each node as percentage of 1,000 replicates. The scale bar represents the estimated number of substitutions per site. Nucleotide sequences obtained in this study were deposited in GenBank under accession nos. DQ522116–DQ522122. Nucleotide sequences of reference strains: DSV-USA93 (GenBank accession no. U04469, genotype GI/3), Musgrov-GBR00 (AJ277614, GI/5), Hesse-DEU98 (AF093797, GI/6), Wnchest-GBR00 (AJ277609, GI/7), and Boxer-USA02 (AF538679, GI/8).