Whole genomic analysis of a porcine G6P[13] rotavirus strain

We report here the whole genomic analysis of an unusual porcine G6P[13] rotavirus-A (RVA) strain, RVA/Pig-wt/IND/HP113/2002/G6P[13], detected from a diarrheic piglet in eastern India in 2002. Strain HP113 exhibited a G6-P[13]-I2-R1-C1-M1-A1-N1-T7-E1-H1 genotype constellation, not reported previously. The VP1, VP3, VP4, NSP1 and NSP3-NSP5 genes of RVA strain HP113 were found to be closely related to those of porcine and/or porcine-like human RVAs. On the other hand, the NSP2 gene of HP113 was found to share a more common origin with those of several recent and archival human Wa-like RVA strains than those of other RVAs, whilst its VP6 and VP7 genes appeared to be derived from co-circulating bovine RVAs from India. Within the VP7-G6 genotype, strain HP113 and the Indian bovine RVAs appeared to constitute a new G6 lineage, tentatively designated as G6 lineage-VI. Based on the available data, it was difficult to pinpoint the porcine or human origin of VP2 gene of HP113. Taken together, whole genomic analysis of strain HP113 revealed important insights into the complex evolutionary patterns of atypical porcine RVAs, providing evidence for reassortment events involving strains from different host species and evolutionary relationships between porcine and human RVAs. To our knowledge, this is the first report on whole genomic analysis of a G6P[13] RVA strain.