VP7 was the only gene segment of this strain with significant genetic identity to human strains.

To investigate the reason why the strains were untypeable, nucleotide sequencing of the VP7 genes was performed.

The outer capsid proteins VP4 and VP7 are highly variable and represent the major neutralizing antigens.

Furthermore, a comparative analysis of the deduced amino sequences form VP7 genes of G1 rotaviruses from 12 countries indicated that four distinct lineages have evolved.

Thirty percent of samples in this study were mixed infections and 21 (16.7%) specimens remained untypeable either for the VP7 or for the VP4 gene.