Abstract
The genome of avian reoviruses is comprised of 10 segments of double-stranded (ds)RNA. Analysis by polyacrylamide gel electrophoresis of the genomic RNA from a small number of avian reoviruses has demonstrated a significant polymorphism in the migration pattern of the dsRNA segments among different isolates. Comparison of these patterns with that of the mammalian reovirus of serotype 1 has permitted calculation of the molecular weights of the avian dsRNA species.