Sequence analysis of the gene (6) encoding the major capsid protein (VP6) of group C rotavirus: higher than expected homology to the corresponding protein from group A virus.

Two overlapping c-DNA clones, which hybridized in Northern blots to RNA segment 6 of the prototype strain (Cowden) of group C rotavirus, were selected from a c-DNA library in pBR322 and sequenced. The gene 6 sequence obtained was 1349 nucleotides and contained a single long open reading frame encoding a protein of 394 amino acids (total MW, 44,479) which is in line with the size of the major capsid protein VP6. Comparison of the group C sequence with that of the corresponding group A rotavirus gene revealed homology levels of 55 and 42% for nucleotides and amino acids, respectively. These values were surprisingly high in view of previous immunological and nucleic acid hybridization data which failed to show any cross-reaction between group A and non-group A rotaviruses. The epidemiological implications of these observations are discussed.