title: Genetic variation in the VP7 gene of rotavirus G1P[8] strains isolated in Vietnam, 1998-2009.
abstract: Group A rotavirus genotype G1P[8] is the most common strain affecting humans around the world over the past few decades. In this study, we examined genetic variation in the VP7 gene of rotavirus G1P[8] strains, detected in children of four major cities of Vietnam during three different rotavirus seasons: 1998-1999, 2007-2008 and 2008-2009 in order to assess the evolution of the virus over 11 years. Fecal samples (n=73) from children hospitalized for gastroenteritis caused by G1P[8] rotavirus were analyzed by DNA sequencing of gene 9 encoding the VP7 capsid protein. Phylogenetic analyses indicated that VP7 gene of the G1 strains from 1999 contained a lineage I, while rotaviruses from 2009 clustered in lineage II. Both of these lineages were found co-circulating in 2007-2008 season. While different sublineages of lineage I and II co-circulated in the 1998-1999 and 2007-2008 seasons, almost all strains in 2009 belonged to sub-lineage II-C. In the analysis using selected 10 strains, the VP4 genes of these 2 VP7-G1 lineages were all grouped in F45-like cluster. Deduced amino acid analyses indicated that there were thirteen amino acid substitutions between strains of two lineages. Of those, two were found in antigenic regions A and C, implying possible antigenic differences between these two lineages. The G1P[8] strains in Vietnam are very genetically diverse and dynamic, implying the frequent monitoring on evolution of rotavirus will be important to assess efficacy of rotavirus vaccine in Vietnam.
authors.affiliation: The National Institute of Hygiene and Epidemiology, Ha Noi, Viet Nam.
authors.forename: Nguyen Van
authors.initials: NV
authors.lastname: Trang
authors.forename: Tetsu
authors.initials: T
authors.lastname: Yamashiro
authors.forename: Le Thi Kim
authors.initials: le TK
authors.lastname: Anh
authors.forename: Vu Thi Bich
authors.initials: VT
authors.lastname: Hau
authors.forename: Le Thi
authors.initials: le T
authors.lastname: Luan
authors.forename: Dang Duc
authors.initials: DD
authors.lastname: Anh
mesh_terms: D000956:Antigens, Viral / Q000235:genetics*; D036022:Capsid Proteins / Q000235:genetics*; D002675:Child, Preschool; D016000:Cluster Analysis; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D005759:Gastroenteritis / Q000453:epidemiology / Q000821:virology; D014644:Genetic Variation; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D012401:Rotavirus / Q000235:genetics* / Q000302:isolation & purification; D012400:Rotavirus Infections / Q000453:epidemiology* / Q000821:virology*; D017422:Sequence Analysis, DNA; D014744:Vietnam / Q000453:epidemiology
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D004279:DNA, Viral; C050779:VP7 protein, Rotavirus