title: Full genome analysis of group B rotaviruses from western India: genetic relatedness and evolution.
abstract: To date, full-genome sequences of only seven human group B rotavirus (RVBs) strains have been described. Such data on more RVBs are necessary to establish the evolutionary relationship and ecological features of RVBs from different geographical regions. The present study was aimed at determining the full-length sequences of all 11 genes of 13 human RVB strains detected during 1995-2010 in sporadic and outbreak cases of acute gastroenteritis from four different cities of western India. This study also included estimation of evolutionary rates and site-specific selection pressure analysis for all gene segments. Nucleotide/deduced amino acid sequence analyses of structural and non-structural genes showed 95.1-99.8/94.1-100 % identity with the counterparts of RVB strains isolated in India, Bangladesh and Myanmar. Phylogenetic analyses of all gene segments revealed formation of a monophyletic clade of the western Indian RVB strains, reflecting their highly conserved nature. All gene segments were also found to be under negative/purifying selection pressure. These data suggest that RVB is circulating in the natural host as a series of stable viral clones. Estimates of rates of nucleotide substitution in all RVBs ranged from 1.36-4.78×10(-3) substitutions per site per year. The rate for human RVB VP7 and NSP2 genes were comparable, respectively, with the evolution kinetics of genotype G9/G12 and N1 group A rotavirus strains. The time of the most recent common ancestor of the extant human RVBs was estimated to be during 1915-1974. Evolutionary and genetic analyses carried out in this study provide data that is useful for the elucidation of evolutionary relationship/timescale, stasis or dynamics existing in the RVB population.
authors: Enteric Viruses Group, National Institute of Virology, 20-A, Dr. Ambedkar Road, PO Box 11, Pune 411001, India.
authors: Anismrita
authors: A
authors: Lahon
authors: Bionformatics Group, National Institute of Virology, 20-A, Dr. Ambedkar Road, PO Box 11, Pune 411001, India.
authors: Atul M
authors: AM
authors: Walimbe
authors: Enteric Viruses Group, National Institute of Virology, 20-A, Dr. Ambedkar Road, PO Box 11, Pune 411001, India.
authors: Shobha D
authors: SD
authors: Chitambar
mesh_terms: D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D001459:Bangladesh; D001483:Base Sequence; D019143:Evolution, Molecular; D016679:Genome, Viral; D005838:Genotype; D006801:Humans; D007194:India; D008875:Middle Aged; D008969:Molecular Sequence Data; D002052:Myanmar; D010802:Phylogeny; D012401:Rotavirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000235:genetics / Q000821:virology*; D017422:Sequence Analysis, DNA; D017361:Viral Nonstructural Proteins / Q000235:genetics
chemical_list: D017361:Viral Nonstructural Proteins