Genomic characterization of G3P[6], G4P[6] and G4P[8] human rotaviruses from Wuhan, China: Evidence for interspecies transmission and reassortment events.
We report here the whole genomic analyses of two G4P[6] (RVA/Human-wt/CHN/E931/2008/G4P[6], RVA/Human-wt/CHN/R1954/2013/G4P[6]), one G3P[6] (RVA/Human-wt/CHN/R946/2006/G3P[6]) and one G4P[8] (RVA/Human-wt/CHN/E2484/2011/G4P[8]) group A rotavirus (RVA) strains detected in sporadic cases of diarrhea in humans in the city of Wuhan, China. All the four strains displayed a Wa-like genotype constellation. Strains E931 and R1954 shared a G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1 constellation, whilst the 11 gene segments of strains R946 and E2484 were assigned to G3-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1 and G4-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 genotypes, respectively. Phylogenetically, the VP7 gene of R946, NSP3 gene of E931, and 10 of 11 gene segments of E2484 (except for VP7 gene) belonged to lineages of human RVAs. On the other hand, based on available data, it was difficult to ascertain porcine or human origin of VP3 genes of strains E931 and R946, and NSP2 genes of strains R946 and R1954. The remaining genes of E2484, E931, R946 and R1954 were close to those of porcine RVAs from China, and/or porcine-like human RVAs. Taken together, our observations suggested that strain R1954 might have been derived from porcine RVAs, whilst strains R946 and E931 might be reassortants possessing human RVA-like gene segments on a porcine RVA genetic backbone. Strain E2484 might be derived from reassortment events involving acquisition of a porcine-like VP7 gene by a Wa-like human RVA strain. The present study provided important insights into zoonotic transmission and complex reassortment events involving human and porcine RVAs, reiterating the significance of whole-genomic analysis of RVA strains.
Recombination Or ReassortmentExtraction confidence 0.95
Key finding
Human strains R946 and E931 are reassortant rotaviruses with human-like segments on a porcine genetic backbone, and strain E2484 shows porcine-human segment exchange through reassortment.
Our observations suggested that strain R1954 might have been derived from porcine RVAs, whilst strains R946 and E931 might be reassortants possessing human RVA-like gene segments on a porcine RVA genetic backbone. Strain E2484 might be derived from reassortment events involving acquisition of a porcine-like VP7 gene by a Wa-like human RVA strain.
Event type
reassortment
Recombination Or ReassortmentExtraction confidence 0.95
Key finding
Human rotavirus strain E2484 shows reassortment involving acquisition of a porcine-like VP7 gene into a human Wa-like genetic background.
Strain E2484 might be derived from reassortment events involving acquisition of a porcine-like VP7 gene by a Wa-like human RVA strain.
Event type
reassortment
Genes or segments
VP7
Cross Species Transmission1 records
Cross Species TransmissionExtraction confidence 0.95
Key finding
Porcine rotaviruses and porcine-like rotavirus lineages have exchanged gene segments, supporting cross-species transmission between different non-human animal hosts.
The remaining genes of E2484, E931, R946 and R1954 were close to those of porcine RVAs from China, and/or porcine-like human RVAs. Taken together, our observations suggested that strain R1954 might have been derived from porcine RVAs, whilst strains R946 and E931 might be reassortants possessing human RVA-like gene segments on a porcine RVA genetic backbone.
Whole genome and phylogenetic analyses showed that human rotavirus strains from Wuhan possess gene segments derived from both human and porcine lineages, supporting reassortment and zoonotic origins.
We report here the whole genomic analyses of two G4P[6] (RVA/Human-wt/CHN/E931/2008/G4P[6], RVA/Human-wt/CHN/R1954/2013/G4P[6]), one G3P[6] (RVA/Human-wt/CHN/R946/2006/G3P[6]) and one G4P[8] (RVA/Human-wt/CHN/E2484/2011/G4P[8]) group A rotavirus (RVA) strains detected in humans in Wuhan, China. Phylogenetically, the VP7 gene of R946, NSP3 gene of E931, and 10 of 11 gene segments of E2484 (except for VP7 gene) belonged to lineages of human RVAs. The remaining genes were close to porcine RVAs, suggesting reassortment and interspecies transmission.
Genes or proteins
VP7; NSP3; VP3; NSP2
Analysis methods
whole genome analysis; phylogenetic analysis
Spillover Event1 records
Spillover EventExtraction confidence 0.85
Key finding
Human group A rotavirus strains in Wuhan exhibited porcine-derived genomic segments, indicating direct porcine-to-human spillover events.
Our observations suggested that strain R1954 might have been derived from porcine RVAs, whilst strains R946 and E931 might be reassortants possessing human RVA-like gene segments on a porcine RVA genetic backbone. The present study provided important insights into zoonotic transmission and complex reassortment events involving human and porcine RVAs.
