title: Location on the evolutionary trees of the non-structural protein (NS) and neuraminidase (NA) genes of late human influenza A (H2N2) viruses: parental viruses of the NS and NA genes of Hong Kong influenza A (H3N2) viruses.
abstract: The nucleotide sequences of the non-structural protein (NS) and neuraminidase (NA) genes of human influenza A (H2N2) viruses isolated in 1967 and 1968 in Europe, Asia and North and South America were located on evolutionary trees in order to identify the parental virus of Hong Kong influenza A (H3N2) viruses, which appeared in the human population in 1968. From the evolutionary trees, the H2N2 viruses isolated during the 1967 to 1968 period were divided into two groups. Group I includes that A/Tokyo/3/67, A/Hachioji/1/67, A/Perg/1/68, A/Cordoba/522/67, A/Texas/2/68 and A/Berkeley/1/68 viruses, whereas group II includes the A/Georgia/1/67, A/England/10/67 and A/Poland/6/67 viruses. The NS and NA genes of Hong Kong H3N2 viruses isolated in 1968 were genetically closer to those of group II viruses and closest to those of A/Poland/6/67.
authors.affiliation: Department of Virology, Medical School, Nagoya City University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Nakao
authors.forename: K
authors.initials: K
authors.lastname: Nakajima
authors.forename: S
authors.initials: S
authors.lastname: Nakajima
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D006723:Hong Kong; D006801:Humans; D053121:Influenza A Virus, H2N2 Subtype; D053122:Influenza A Virus, H3N2 Subtype; D009980:Influenza A virus / Q000201:enzymology / Q000235:genetics*; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000235:genetics*; D017361:Viral Nonstructural Proteins / Q000235:genetics*
chemical_list: D017361:Viral Nonstructural Proteins; D009439:Neuraminidase