2009年新型甲型H1N1流感病毒全基因组序列重组分析

目的:分析2009年流行的新型甲型流感病毒（A/H1N1）全序列的基因重组现象。方法:从NCBI基因数据库下载2009年新型甲型流感病毒（A/H1N1）全基因组序列，采用Molecular Evolutionary Genetics Analysis version 4.0（MEGA 4.0）软件对8条基因序列进行拼接和比对，分析2009年爆发株与历史流行株序列间的同源性；同时采用Simplot 3.5.1软件分析新型流感病毒A/H1N1基因重组现象。结果:2009年3月以来爆发的新型A/H1N1病毒株聚合酶B1(polymerase B1,PB1)基因来自于人H3N2，其同源性为93.7%；聚合酶B2 (polymerase B2,PB2)和聚合酶A (polymerase A,PA)与禽H5N1同源性较高，同源性分别为89.0%、89.9%；血凝素(hemagglutinin,HA)、核蛋白(nucleoprotein,NP)和非结构蛋白(non-structural protein,NS)与北美地区猪H1N1同源性较高，同源性分别为91.7%、93.1%和93.1%；神经氨酸酶(neuraminidase,NA)和基质蛋白(matrix protein,MP)与欧洲地区猪H1N1同源性较高，同源性分别为90.5%、95.5%。全基因序列同源性分析发现2009年新型A/H1N1病毒与北美地区猪H1N1病毒同源性最高，为83.9%。结论:2009年新型甲型H1N1流感病毒可能是人H3N2、北美地区猪H1N1、欧洲地区猪H1N1、禽H5N1的基因重排病毒。

Recombination analysis of full-length genomic sequences of novel influenza virus A/H1N1 in 2009 pandemic

. Objective:To analyze the recombination of full-length genomic sequences of novel influenza virus A/H1N1 in 2009 pandemic.Methods:The full-length sequences of the novel A/H1N1 and reference sequences were downloaded from NCBI database. MEGA4.0 software was used to connect, align sequences, and analyze the similarity between the full-length sequences of the novel virus and each of the reference strains.Recombination was analyzed by Simplot software (version 3.5.1).Results:Simplot analysis indicated that the PB1 genes (polymerase B1, PB1) of the novel A/H1N1 viruses might evolve from human H3N2 virus (identity:93.7%); the PB2 genes (polymerase B2, PB2) and the PA genes (polymerase A, PA) might evolve from avian H5N1 viruses (identity:89.0%, 89.9%, respectively); the HA genes (hemagglutinin, HA), the NP genes (nucleoprotein, NP) and the NS genes (non-structural protein, NS) showed high similarities with those of swine H1N1 viruses isolated in North America (identity:91.7%, 93.1%, and 93.1%, respectively); and the NA genes (neuraminidase, NA) and the MP genes (matrix protein, MP) might evolve from European swine H1N1 viruses (identity:90.5%, 95.5%, respectively). The full-length sequence of the novel A/H1N1 viruses had a highest similarities with swine H1N1 viruses isolated in North America (identity:83.9%).Conclusion:The novel influenza virus A/H1N1 is a recombinant virus evolving from human H3N2 viruses, swine H1N1 from North America, swine H1N1 from Europe, and swine H5N1 from Asia.