Amino acid replacements of the polymorphic locuses of the hemaglutinin, neuraminidasa and nucleoprotein genes of the influenza virus A strains H1N1 and H7N9

Aim. Significant variability contributing to the formation of highly virulent variants, widespread distribution in natural reservoirs, the ability to overcome interspecific barriers and the ease of the airborne pathway contribute to the development of epidemics and pandemics of respiratory infections. Determination of polymorphic sites and type of polymorphism of the investigated virus subtype gene sequences will allow to determine amino acid substitutions and to establish RNA targets for genotyping. Methods. The analysis was performed on the nucleotide sequences of genes HA, NA and NP of strains H1N1 and H7N9 of avian influenza A virus obtained from the NCBI base. Amino acid sequences of genes were obtained by translation of nucleotide gene sequences using MEGA 6. Polymorphic loci and cluster analysis were performed using MEGA 6 using the ClustalW algorithm.Results. The nucleotide sequences of HA, NA and NP genes were investigated, as well as their translation products inavian influenza A strains H1N1 and H7N9. The polymorphic regions and type of polymorphism of the sequences were determined. Conclusions. Polymorphism regions were detected on the nucleotide sequences of the HA, NA, and NP genes (H1N1 and H7N9 strains) and their translation products. The polymorphism of the HA, NA, and NP genes (strain H1N1) is shown to be higher than the polymorphism of HA, NA, and NP (strain H7N9) due to the presence in the first significant number of synonymous triplets. Keywords: influenza A virus, hemagglutinin, neuraminidase, nucleoprotein, polymorphism.