title: Multiple-gene characterization of rotavirus strains: evidence of genetic linkage among the VP7-, VP4-, VP6-, and NSP4-encoding genes.
abstract: A total of 162 rotavirus strains detected between 1996 and 2006 among individuals with diarrhea in Rio de Janeiro, Brazil, were analyzed by multiple-gene genotyping. Characterization of strains was done by RT-PCR assay for amplification and typing of the VP7-, VP4-, VP6-, and NSP4-encoding genes. Overall, 139 (85.8%) strains belonged to the common group A rotavirus combinations: 67 (41.4%) belonged to genotype G1-P[8]-I1-E1; 18 (11.1%) were G2-P[4]-I2-E2; 11 (6.8%) were G3-P[8]-I1-E1; 12 (7.4%) were G4-P[8]-I1-E1; and 31 (19.1%) were G9-P[8]-I1-E1. Two samples presented mixed genotypes (G1 + G3-P[8]-I1-E1 and G1 + G9-P[9]-I1-E1) and rare combinations, such as G2-P[6]-I2-E2 and G9-P[6]-I2-E2, were detected in six (3.7%) strains. The results suggest a linkage among all four genes. Genotypes G1/G3/G4/G5/G9-P[8] were correlated strongly to I1-E1 genotypes and G2-P[4]/P[6] were correlated to I2-E2 genotypes. Unusual combinations of genes, such as G3-P[9]-I2-E2, G9-P[9]-I1-E2, and G3-P[9]-I3-E3, were observed in 15 (9.3%) strains. The characterization of multiple genes allows a more complete analysis of the rotavirus isolates and provides evidence of natural reassortment of strains.
authors.affiliation: Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Fabrício José
authors.initials: FJ
authors.lastname: Benati
authors.forename: Adriana G
authors.initials: AG
authors.lastname: Maranhão
authors.forename: Rodrigo S
authors.initials: RS
authors.lastname: Lima
authors.forename: Raquel Cirlene
authors.initials: RC
authors.lastname: da Silva
authors.forename: Norma
authors.initials: N
authors.lastname: Santos
mesh_terms: D000956:Antigens, Viral / Q000235:genetics*; D001938:Brazil; D036022:Capsid Proteins / Q000235:genetics*; D002675:Child, Preschool; D016000:Cluster Analysis; D003967:Diarrhea / Q000821:virology; D008040:Genetic Linkage; D005838:Genotype; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D012367:RNA, Viral / Q000235:genetics; D011995:Recombination, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012401:Rotavirus / Q000235:genetics*; D012400:Rotavirus Infections / Q000821:virology; D017422:Sequence Analysis, DNA; D014118:Toxins, Biological / Q000235:genetics*; D017361:Viral Nonstructural Proteins / Q000235:genetics*
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D006023:Glycoproteins; C081369:NS28 protein, rotavirus; D012367:RNA, Viral; D014118:Toxins, Biological; C060339:VP4 protein, Rotavirus; C061332:VP6 protein, Rotavirus; C050779:VP7 protein, Rotavirus; D017361:Viral Nonstructural Proteins