Liu Y, Jiang L Y, Luo L, Cao Y M, Jing Q L, Yang Z C
Disinfection Department, Guangzhou Center for Disease Control and Prevention, Guangzhou 510440, China.
Virus Department, Guangzhou Center for Disease Control and Prevention, Guangzhou 510440, China.
Zhonghua Liu Xing Bing Xue Za Zhi. 2017 Jan 10;38(1):90-95. doi: 10.3760/cma.j.issn.0254-6450.2017.01.018.
To investigate the molecular characteristics of dengue virus serotype 2 (DENV2) in Guangzhou during 2001-2015, and analyze the E gene of the strains isolated, the phylogenetic tree and molecular clock were constructed to know about the evolution of the strains. The serum samples of the patients were detected by real time PCR, and positive samples were used to isolate dengue virus by using C6/36 cells. The E gene of the isolated strains were sequenced. The phylogenetic tree was constructed by using software Mega 4.0, and the molecular clock was drawn by using software BEASTv1.8.2. Twenty-six dengue virus strains were isolated between 2001 and 2015. They were all clustered into 2 genotypes, i.e. cosmopolitan genotype and Asian genotype Ⅰ. The strains isolated in Guangzhou shared high homology with Southeast Asian strains. The cosmopolitan genotype was divided into 2 sub-genotype at about 46 and 35 years ago. The substitution rate of dengue virus serotype 2 in Guangzhou was 7.1 × 10(-4) per year per site. There were close relationship between the Guangzhou strains and Southeast Asian strains. Guangzhou was at high risk of imported dengue fever, outbreak of dengue hemorrhagic fever and dengue shock syndrome. There might be two ways of introduction of cosmopolitan genotype. The substitution rate of the strains in Guangzhou was similar to that in the neighbor countries.
为研究2001 - 2015年广州地区登革病毒2型（DENV2）的分子特征，并分析分离株的E基因，构建系统发育树和分子钟以了解毒株的进化情况。采用实时荧光定量PCR检测患者血清样本，阳性样本利用C6/36细胞分离登革病毒，对分离株的E基因进行测序。使用Mega 4.0软件构建系统发育树，使用BEASTv1.8.2软件绘制分子钟。2001年至2015年共分离出26株登革病毒，均聚为2个基因型，即泛在基因型和亚洲基因型Ⅰ。广州分离株与东南亚毒株具有高度同源性。泛在基因型在约46年和35年前分为2个亚基因型。广州地区登革病毒2型的替换率为每年每个位点7.1×10(-4)。广州毒株与东南亚毒株关系密切。广州存在输入性登革热、登革出血热和登革休克综合征暴发的高风险。泛在基因型可能有两种引入方式。广州毒株的替换率与周边国家相似。
