Evolution of P[8], P[4], and P[6] VP8* genes of human rotaviruses globally reported during 1974 and 2017: possible implications for rotavirus vaccines in development

Figures & data

Figure 1. Maximum likelihood phylogenetic trees of VP8* subunit nucleotide sequences (amino acids 64-223 of VP4) of the (a) P[8], (b) P[4], and (c) P[6] global human rotaviruses (1974–2017) and the trivalent P2-VP8 subunit vaccine strains. Vaccine strains Wa, DS-1 and 1076 are indicated by a black circle and bootstrap values greater than 70% are indicated in each node. The scale bar indicates number of substitution per site

Figure 2. Genetic distances of the VP8* subunit sequences (amino acids 64–223 of VP4) between global P[8], P[4], and P[6] human rotavirus strains and the trivalent P2-VP8 subunit vaccine strains at (a) the nucleotide level and (a) the amino acid level. Vaccine strains are positioned in the center and the mean percentage difference is represented with a filled triangle (P[8]), circle (P[4]), or asterisk (P[6]). A higher genetic distance to the vaccine strains is indicated by a more outward position. Numbers of sequences retrieved per strain and regions are indicated in Supplementary Table 1

Figure 3. Phylogenetic relationship and changes of VP8* subunit sequences of P[8] RV strains reported in the USA from 1974 to 2013. (a): Phylogenetic tree of the VP8* subunit sequences of the 506 P[8] rotaviruses and the strain Wa (1974), which is indicated by a black circle. Bootstrap values greater than 70% are indicated in each node. The scale bar indicates number of substitution per site. (b): Genetic distance at amino acid level between circulating strains and the prototype Wa strain by three periods of time