Identification of two lineages (WA-like and F45-like) within the major rotavirus genotype P[8]

The fourth gene of a porcine (S8) and eight human rotavirus isolates posses sing the major human VP4 specificity (P1A serotype and/or P[8] genotype) we re partially sequenced and compared to other available P[8] sequences from rotaviruses types G1, G3, G5 and G9 specificities which had bern originally recovered from children with diarrhea in Japan, Brazil and the USA. Brazil ian rotavirus S8 represented the single known porcine rotavirus with this P specificity. Phylogenetic analysis revealed two lineages or subgenotypes w ithin P[8] strains: the F45-like P subgenotype comprised most of the strain s, including all the human G5 isolates analyzed, whereas the Wa- or S8-like subgenotype consisted of only a human isolate obtained in the same geograp hic region as S8 and an American strain with atypical RNA profile besides t he prototypes Wa and S8 viruses. A conserved basic amino acid residue at po sition 131 in VP4 seemed characteristic of the F45-like P[8] subgenotype. ( C) 1999 Elsevier Science B.V. All rights reserved.