title: Sequence analysis of the VP7 gene of human rotavirus G1 isolated in Japan, China, Thailand, and Vietnam in the context of changing distribution of rotavirus G-types.
abstract: Over the last decade, rotavirus G1 has represented the most common genotype worldwide. Since 2000, the prevalence of rotavirus G1 has decreased in some countries such as Japan and China. To monitor the trend of the VP7 encoding gene of rotavirus G1, we performed a sequence analysis of 74 G1 rotavirus strains isolated in Japan, China, Thailand, and Vietnam during the period from 2002 to 2005. The phylogenetic tree showed that all of the studied G1 strains from the four countries clustered into lineage III, the same as the majority of the G1 strains isolated in China and Japan in 1990 and 1991. Examination of the deduced amino acid sequences of the G1 strains from China and Japan revealed an amino acid substitution at position 91 (Asn instead of Thr) in antigenic region A when compared to the G1 strains isolated in China and Japan in 1990, 1991, and global reference strains. For the G1 strains from Thailand and Vietnam, there were three amino acid substitutions, not belonging to any antigenic regions. The study showed that there have been no considerable changes of human rotavirus G1 isolated in Japan, China, Thailand, and Vietnam. Further studies need to be carried out for a better understanding of why such changes in the prevalence of rotavirus G1 occur in these countries.
authors.affiliation: Department of Developmental Medical Sciences, Institute of International Health, Graduate School of Medicine, University of Tokyo, Japan.
authors.forename: Quang Duy
authors.initials: QD
authors.lastname: Trinh
authors.forename: Tuan Anh
authors.initials: TA
authors.lastname: Nguyen
authors.forename: Tung Gia
authors.initials: TG
authors.lastname: Phan
authors.forename: Pattara
authors.initials: P
authors.lastname: Khamrin
authors.forename: Hainian
authors.initials: H
authors.lastname: Yan
authors.forename: Phuc Le
authors.initials: PL
authors.lastname: Hoang
authors.forename: Niwat
authors.initials: N
authors.lastname: Maneekarn
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Yagyu
authors.forename: Shoko
authors.initials: S
authors.lastname: Okitsu
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ushijima
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000956:Antigens, Viral / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D036022:Capsid Proteins / Q000235:genetics* / Q000276:immunology; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D017931:DNA Primers / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D005814:Genes, Viral; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D012401:Rotavirus / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000453:epidemiology* / Q000821:virology*; D017386:Sequence Homology, Amino Acid; D013785:Thailand / Q000453:epidemiology; D013997:Time Factors; D014744:Vietnam / Q000453:epidemiology
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D017931:DNA Primers; D004279:DNA, Viral; C050779:VP7 protein, Rotavirus