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为了解北京地区人呼吸道合胞病毒(human respiratory syncytial virus,HRSV)的遗传变异和分子流行病学特征,首次对北京地区2003~2004年63株HRSV分离株进行了G基因3′末端的第2个高度变异区的序列测定,并进行了基因分型和遗传变异的分析。使用不同的型特异性引物对GPA-F1和GPB-F1分别扩增A、B血清型HRSVG基因3′末端核苷酸序列,特异性扩增产物和随后的序列测定结果均显示,北京地区2003~2004年63株HRSV毒株中,96.8%(61/63)为A血清型,3.2%(2/63)为B血清型,说明北京地区在2003~2004年间存在HRSV A、B血清型共循环,但以A血清型病毒为主。分别对北京流行的A和B血清型病毒进行了基因亲缘性关系分析,结果提示,61株北京A血清型分离株全部为GA2基因型;2株B血清型分离株为GB3基因型。由此看来,GA2基因型是北京地区2003~2004年的优势流行基因型。北京61株GA2分离株之间核苷酸和氨基酸同源性分别在87.8%~100%和77.9%~100%之间;2株B血清型分离株之间核苷酸和氨基酸同源性分别为94.7%和88.1%。这说明在2003年和2004年有很多个不同的GA2基因型HRSV毒株在北京地区共循环,北京地区的HRSV流行存在着许多由不同病毒株引起的传播链。B血清型分离株Beijing04-11于G基因3′末端含有一个60个碱基的重复序列,这是HRSV多聚酶易于重复复制限定序列的一个极端的例子,有可能是HRSV逃逸免疫压力而不断进化的一种方式。该研究首次对北京地区2003年和2004年流行的HRSV进行了基因分型和遗传变异的研究,对于了解北京HRSV流行株的基因特征具有重要意义,可以为北京乃至中国疫苗株的选择提供参考依据,从而指导HRSV的免疫预防控制。
In order to understand the genetic variation and molecular epidemiological characteristics of human respiratory syncytial virus (HRSV) in Beijing area, 63 HRSV isolates from 2003 to 2004 in Beijing were investigated for the first 3 A highly variable region of the sequence determination, and the genotyping and genetic variation analysis. Using different type-specific primers to amplify the 3’-terminal nucleotide sequences of A, B serotypes HRSVG gene respectively, GPA-F1 and GPB-F1, specific amplification products and subsequent sequencing results showed that Beijing region 2003 Among 63 strains of HRSV in 2004, 96.8% (61/63) were serotype A and 3.2% (2/63) were serotype B, indicating that serotypes HRSV A and B were present in Beijing from 2003 to 2004 Circulation, but the main A-type virus. The gene-related relationship analysis of serogroup A and B viruses in Beijing was carried out. The results showed that all the 61 strains of Beijing A serotypes were GA2 genotypes and 2 strains of B serotypes were GB3 genotypes. In view of this, GA2 genotype is the prevalent genotype in Beijing from 2003 to 2004. The nucleotide and amino acid homologies of 61 GA2 isolates in Beijing ranged from 87.8% to 100% and from 77.9% to 100%, respectively. The nucleotide and amino acid homologies between the two isolates of serogroup B 94.7% and 88.1%. This shows that in 2003 and 2004, there are many different GA2 genotype HRSV strains circulating in Beijing. There are many transmission chains of HRSV in Beijing caused by different virus strains. The B serotype Beijing04-11 contains a 60-base repeat at the 3 ’end of the G gene. This is an extreme example of the ease with which HRSV polymerases can replicate in defined sequences. It is likely that HRSV evolved to evolve immune pressure a method. This study, for the first time, investigated the genotyping and genetic variation of HRSVs prevailing in Beijing and 2003 and 2004, and is of great significance for understanding the genetic characteristics of HRSV strains in Beijing and may provide reference for the selection of vaccine strains in Beijing and China. , Thus guiding the immunosuppressive control of HRSV.