title: Comparison of selection pressures on the HA gene of pandemic (2009) and seasonal human and swine influenza A H1 subtype viruses.
abstract: The 2009 human pandemic influenza (H1N1) virus possesses the HA gene of the H1 subtype. The evolutionary process of the 2009 H1N1 virus remains to be defined. We performed genetic analyses of the HA gene by comparing the 2009 H1N1 virus with seasonal human and swine viruses. We analyzed sequences of 116 2009 H1N1 viruses, and obtained 1457 seasonal H1N1, 365 swine H1, and 1332 2009 H1N1 viruses from the database. Selection pressure for the 2009 H1N1 virus was higher than that for the swine virus and equivalent to that for the seasonal virus. Positions 206 and 264 were found to be positively selected sites. We also identified sites under different selection pressures from the seasonal or swine virus that may be involved in imparting significant biological characteristics. The evolutionary characteristics of the H1 gene of the 2009 H1N1 virus differed from those of seasonal and swine viruses.
authors.affiliation: Department of Virology, Tohoku University Graduate School of Medicine, Sendai, 980-8575, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Furuse
authors.forename: Kozue
authors.initials: K
authors.lastname: Shimabukuro
authors.forename: Takashi
authors.initials: T
authors.lastname: Odagiri
authors.forename: Rumi
authors.initials: R
authors.lastname: Sawayama
authors.forename: Takashi
authors.initials: T
authors.lastname: Okada
authors.forename: Irona
authors.initials: I
authors.lastname: Khandaker
authors.forename: Akira
authors.initials: A
authors.lastname: Suzuki
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Oshitani
mesh_terms: D000818:Animals; D004196:Disease Outbreaks; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics*; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification / Q000235:genetics*; D007251:Influenza, Human / Q000821:virology*; D009976:Orthomyxoviridae Infections / Q000662:veterinary / Q000821:virology; D012621:Seasons; D012641:Selection, Genetic; D013552:Swine / Q000821:virology*; D013553:Swine Diseases / Q000821:virology
chemical_list: C543345:H1N1 virus hemagglutinin; D019267:Hemagglutinin Glycoproteins, Influenza Virus