浙江省2002-2006年禽流感H5N1病毒基因特性与进化重组分析

Molecular characteristics and its evolution of the complete genome of avian influenza H5N1 virus isolated in Zhejiang province from 2002 to 2006

目的对近年来浙江省禽流感病毒H5N1分离株的基因特性与进化重组特征进行分析。方法通过对2002-2006年浙江省禽与人的H5N1病毒株进行全基因序列测定，采用Mega3．0生物信息学软件分析病毒株基因特性并与相关基因型标准病毒株进行系统进化分析。结果2002-2006年浙江省H5N1病毒株HA序列裂解位点序列含多个碱性氨基酸，符合高致病性禽流感病毒特征；与Gs／Guangdong／1／96相比，除Dk／Zhejiang／2／02和Ck／zhejiang／8／03株外其他病毒株均在NA蛋白茎区缺失20个氨基酸。全基因系统进化分析表明，20022003年的分离株遗传基因基本属于当年流行的B、W、X、Y、Z等基因型，但部分病毒株不同基因片段属于不同基因型。结论浙江省禽类中也广泛存在H5N1的基因片段重组现象，2005年后的Ck／Zhejiang／24／05株及人H5N1 Zhejiang／16／06株各遗传基因基本上稳定于近年大陆流行的FJ-like基因型。

Objective To analyze the molecular characteristics and evolution reassortment of the complete genome of avian influenza H5N1 virus isolated in Zhejiang province in recent years. Methods Complete genomes of avian influenza H5N1 viruses isolated in Zhejiang province from 2002 to 2006 were sequenced. Molecular and evolution reassortment characterization of these virus strains were analyzed by Mega 3.0 bioinformaties software. Results Through study on the HA genes from all these strains,our data revealed that there were multiple basic amino acids at the cleavage site, which was typical for HPAIV. Compared with Gs/Guangdong/1/96, all these strains had a 20 amino acid deletion in the stalk of the NA, except for Dk/Zhejiang/2/02 and Ck/Zhejiang/8/03. Results from phylogenetic analysis showed that from 2002 to 2003 the H5N1 viruses belonged to the genotype of B, W, X, Y , Z, and other genotypes were prevailed in corresponding year. However, different gene fragments of several strains belonged to different genotypes. Conclusion Recombinant might be widespread among the poultry in Zhejiang province. The genetic genes of viruses isolated after 2005, the Ck/Zhejiang/24/05 and Zhejiang/16/06 strains were almost all originated from the FJ-like genotype stably,