Nucleotide sequences of the neuraminidase genes of influenza A/Leningrad/134/57 (H2N2) virus and two of its live, attenuated, cold-adapted variants

Virus Genes. 1995;10(1):95-8. doi: 10.1007/BF01724302.


The nucleotide sequences of the neuraminidase (NA) genes of the A/Leningrad/134/57 (H2N2) wild-type (Len/wt) virus as well as two of its live attenuated, cold-adapted (ca) variants, A/Leningrad/134/17/57 (Len/17) and A/Leningrad/134/47/57 (Len/47), were determined. In comparison with Len/wt, one nucleotide change (C-225 to A) was found in the NA gene of Len/17. This change codes for a Thr-to-Asn substitution at position 69 of NA. The NA gene of the more attenuated Len/47 ca virus has one silent (T-814 to C) and two coding nucleotide substitutions, C-78 to T (Ala-20 to Val) and C-225 to A (Thr-69 to Asn). These sequence data were used to design a PCR-restriction technique to determine the origin of the NA gene in candidate live, attenuated vaccine reassortants made by reassorting these ca strains with current field viruses.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA, Viral
  • Genetic Variation
  • Humans
  • Influenza A Virus, H2N2 Subtype*
  • Influenza A virus / enzymology*
  • Influenza A virus / genetics
  • Molecular Sequence Data
  • Neuraminidase / genetics*
  • Reassortant Viruses / genetics


  • DNA, Viral
  • Neuraminidase

Associated data

  • GENBANK/L37329
  • GENBANK/L37330
  • GENBANK/L37331