Genetic analysis of H9N2 avian influenza viruses isolated from India

Arch Virol. 2008;153(8):1433-9. doi: 10.1007/s00705-008-0131-9. Epub 2008 Jun 22.

Abstract

H9N2 avian influenza viruses are endemic in domestic poultry in Asia and are grouped into three major sublineages represented by their prototype strains A/Duck/Hong Kong/Y280/97 (Y280-like), A/Quail/Hong Kong/G1/97 (G1-like) and A/Chicken/Korea/38349-p96323/96 (Korean-like). To understand the genetic relationship of Indian viruses, we determined the partial nucleotide sequence of five H9N2 avian influenza viruses isolated from chicken in India during 2003-2004 and compared them with H9N2 sequences available in GenBank. Deduced amino acid sequence analysis revealed that four isolates shared an R-S-S-R/G motif at the cleavage site of HA, representing low pathogenicity in chickens, while one virus harbors an R-S-N-R/G motif at the same position. All the viruses maintained the human-like motif 226Lysine (H3 numbering) at the HA receptor binding site. Phylogenetic analysis showed that 50% of the genes (HA, NA, NP and M) were similar to G1-like viruses, whereas the remaining genes of the Indian isolates formed a separate, not yet defined, sublineage in the Eurasian lineage. Our finding provides evidence of a novel reassortant H9N2 genotype of G1-like viruses circulating in India.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites / genetics
  • Chickens / virology*
  • Hemagglutinin Glycoproteins, Influenza Virus / chemistry*
  • Hemagglutinin Glycoproteins, Influenza Virus / genetics*
  • Humans
  • India
  • Influenza A Virus, H9N2 Subtype / classification*
  • Influenza A Virus, H9N2 Subtype / genetics
  • Influenza A Virus, H9N2 Subtype / isolation & purification
  • Influenza A Virus, H9N2 Subtype / pathogenicity
  • Influenza in Birds / genetics
  • Influenza in Birds / immunology
  • Influenza in Birds / virology*
  • Phylogeny
  • Poultry Diseases / epidemiology
  • RNA, Viral / genetics
  • Sequence Analysis, DNA

Substances

  • Hemagglutinin Glycoproteins, Influenza Virus
  • RNA, Viral