石家庄市2009年H3N2亚型流感病毒血凝素重链区基因变异分析

Genetic variation analysis on HA1 gene of influenza virus subtype H3N2 in Shijiazhuang in 2009

目的:了解石家庄市2009年H3N2亚型流感病毒流行情况,研究2009年分离H3N2亚型流感病毒株血凝素重链(HA1)的基因特性及变异情况。方法:用MDCK细胞分离流感病毒,采用血抑实验分型鉴定。随机选取24株H3N2亚型流感毒株进行RNA提取、逆转录扩增获得HA1基因产物,将其进行基因序列测定,之后用DNAStar软件的MegAlign功能进行序列比对和分析。结果:经MegAlign将24株毒株与WHO疫苗推荐株A/Wisconsin/67/200(07～08)、A/Bris-bane/10/2007(08～10)进行比对,发现与同年疫苗株同源性较高,为98.2%～98.6%,仅有个别位点出现氨基酸替换。结论:2009年石家庄市H3N2亚型流感毒株HA1区与同年疫苗株基因序列符合率较高,尚未形成一个新的变异株。

Objective：To understand the prevalence of influenza virus subtype H3N2 and to study genetic variation characteristics of HA1 gene of influenza virus subtype H3N2 isolated in Shijiazhuang in 2009.Methods：Influenza viruses isolated were cultured in MDCK cell and subtype was tested by hemagglutination inhibition.There were 24 strains chosen randomly to be tested.Viral RNA was extracted and their HA1 genes were amplified by reverse transcription polymerase chain reaction（RT-PCR）.The PCR products were sequenced,and the gene sequences were compared and analyzed with MegAlign of the biometric software DNAStar.Results：Comparing with A/Wisconsin/67/200（07～08）,A/Brisbane/10/2007（08～10） vaccine strains recommended by WHO,there was a high identity of 98.2%～98.6% in amino acid and several replacements of amino acids was observed.Conclusion：The nucleotide sequence of H3N2 strain in HA1 region is similar to the vaccine strain of the same year and is not a new variant in Shijiazhuang in 2009.