The number of H7N9 bird flu cases was high and the situation was grim in guizhou province in 2017. To understand the molecular characteristics of the hemagglutinin gene (HA) and the risk of human infection with avian influenza virus A(H7N9) in Guizhou Province, 2017. Homology, genetic evolution and pivotal sites related to receptor binding regions, pathogenicity and potential glycosylation of 14 avian influenza viruses A(H7N9) were analyzed by a series of bioinformation softwares. It was cleared that there was 95.9%-100% similarity among 14 strains in nucleotide of the HA gene, and there were 96.8%-97.8% and 96.8%-97.9% similarities with vaccine strains A/Shanghai/2/2013 and A/Anhui/1/2013 recommended by WHO, respectively. Phylogenetic analysis showed that 14 HA genes were directly evolved in the Yangtze River Delta evolution branch, but they could be derived from five diffenrent strains. Then 13 of 14 strains cleavage site sequences of HA protein revealed they were low pathogenic avian influenza viruses, while A/Guizhou-Weining/CSY01/2017 was high pathogenic avian influenza virus. Mutation G186V at the receptor binding sites in the HA was found in all 14 strains, and mutation Q226L in 13 strains besides A/Guizhou-Weining/CSY01/2017. All five potential glycosylation motifs in the HA were conservative.
为了解2017年贵州省H7N9禽流感病毒的分子特征和疾病风险，运用生物信息学软件对14株病毒HA基因的同源性、遗传进化、受体结合关键位点、致病相关和糖基化位点进行分析，明确了其HA基因核苷酸同源性为95.9%~100%，与WHO推荐的A/Shanghai/2/2013和A/Anhui/1/2013疫苗株的同源性分别为96.8%~97.8%和96.8%~97.9%；14株毒株均属于长三角分支，来源于5个不同的毒株；其中13株为低致病性禽流感毒株，而A/Guizhou-Weining/CSY01/2017为高致病性禽流感毒株；受体结合关键位点14株毒株均存在G186V的突变，13株存在Q226L的突变；潜在糖基化位点无变异。.
Keywords: Avian influenza A (H7N9) virus; Genes; Hemagglutinin glycoproteins, influenza virus; Influenza in birds.