NONRANDOM SEGREGATION OF PARENTAL ALLELES IN REOVIRUS REASSORTANTS

To test for nonrandom segregations among their 10 genomic RNA segments , we examined a set of 83 reassortants derived from mammalian reovirus type 1 Lang and type 3 Dearing, After confirming the genotypes of the reassortants, we performed statistical analyses on the distributions of parental alleles for each of the 10 gene segments, as well as for t he 45 possible pairings of the 10 segments, The analyses revealed nonr andom associations of parental alleles in the L1-L2, L1-M1, L1-S1, and L3-S1 segment pairs, at levels indicating high statistical significan ce (P < 0.005). Such associations may reflect specific interactions be tween viral components (protein-protein, protein-RNA, or RNA-RNA) and may influence both the evolution of reoviruses in nature and their gen etic analysis in the laboratory, The data may also support an hypothes is that reovirus reassortants commonly contain mutations that improve their fitness for independent replication.