Polymorphism of genomic RNAs within rotavirus serotypes and subgroups

The genome of human rotaviruses is composed of 11 segments of double stranded RNA. Analysis by polyacrylamide gel electrophoresis of the genomic RNA from a number of strains of the same serotype has demonstrated a significant polymorphism in the migration pattern. However, two strains differing from each other in serotype were found to have apparently identical RNA migration patterns. It is concluded that serotype cannot be deduced from RNA migration patterns. Degrees of polymorphism have been observed within each of three known human rotavirus serotypes.