Nucleotide sequence of the influenza virus A/USSR/90/77 hemagglutinin gene

The complete nucleotide sequence of the hemagglutinin gene of influenza virus A/USSR/90/77 was determined. Comparison of hemagglutinin amino acid sequences from H1 field strains revealed five potential antigenic sites. Four of these sites correspond to those observed for H3 hemagglutinins, whereas the fifth apparently derives from differences in the glycosylation patterns between subtypes.