Phylogenetic analysis of the amino acid sequences of pNoVs-Ch6 and other NoVs. Bootstrap values, expressed as percentages of 1000 replications, are given at the branch points. GenBank accession numbers for the reference strains are marked at each branch points. Tree (A) was constructed based on the complete capsid region. Tree (B) was constructed based on the RdRp region. Strains designation follows the outlines of Wang et al.  and Zheng et al. .