GENES-CODING FOR THE SURFACE GLYCOPROTEINS OF INFLUENZA-A VIRUSES CONTAIN A SMALL CONSERVED AND A LARGE VARIABLE REGION

The variable genes of influenza A viruses coding for hemagglutinin and neuraminidase consist of a relatively small highly conserved region, which is presumably involved in the functional integrity of the gene products, and a relatively large highly variable region, presumably involved in the immunological properties. This is demonstrated by melting profiles of homologous and heterologous RNA hybrid molecules. The results are discussed as a possible mechanism how serologically different influenza strains evolve by mutation in the variable part and selection by the immune system of the host. © 1979.