National Institute for Public Health and the Environment, RIVM, PO Box 1, 3720 BA Bilthoven, The Netherlands.
Infect Genet Evol. 2011 Jul;11(5):886-94. doi: 10.1016/j.meegid.2011.02.011. Epub 2011 Feb 23.
Evolutionary history of human enterovirus 71 (EV71) in the Netherlands shows displacement of virus subgenogroups, that only partly can be explained by antigenic changes. Additionally, occasional epidemics have occurred that remain to be explained. Previous studies have shown subgenogroup specific recombination events in the genome of Asian EV71 strains. To find clues on the role of genome recombination in evolution of the EV71 subgenogroups found in Europe and in the evolution of strains capable of causing outbreaks, we analyzed the genomes of 19 strains representing the genetic diversity of EV71 in the Netherlands between 1963 and 2010. We selected viruses from EV71 endemic and epidemic years (1986 and 2007). Subgenogroup specific genome recombination events were detected for subgenogroup B0, B1 and B2 viruses, in line with observed genome recombination events in Asian subgenogroup B3 and B4 viruses. Considering recombination events distinguishing strains from epidemic years from those of non-epidemic years, breakpoints for recombination were detected in the 5'UTR of B2 viruses from the outbreak in 1986, with highest similarity of the 5'UTR to B4 and B3 strains isolated during outbreaks in the Asian Pacific region. No indications for recombination were found in genogroup C isolates. Except for the '86 B2 isolates' Dutch isolates phylogenetically interspersed with international reference strains of the same subgenogroup, indicating a global dissemination of (recombinant) EV71 viruses. The difference observed in the 5'UTR of EV71 strains isolated in endemic versus epidemic years suggests that changes in the 5'UTR cause evolution of strains capable of causing outbreaks.
荷兰人类肠道病毒 71 型（EV71）的进化史显示病毒亚组群发生了取代，这部分可以通过抗原变化来解释。此外，偶尔还会发生一些仍待解释的流行病。先前的研究表明，亚洲 EV71 株的基因组中存在亚组特异性重组事件。为了寻找基因组重组在欧洲发现的 EV71 亚组群进化和能够引起暴发的株进化中的作用线索，我们分析了代表荷兰 1963 年至 2010 年间 EV71 遗传多样性的 19 株病毒的基因组。我们选择了 EV71 地方性和流行年份（1986 年和 2007 年）的病毒。检测到亚组群 B0、B1 和 B2 病毒的亚组特异性基因组重组事件，与亚洲亚组群 B3 和 B4 病毒观察到的基因组重组事件一致。考虑到将流行年份的病毒株与非流行年份的病毒株区分开来的重组事件，在 1986 年暴发的 B2 病毒的 5'UTR 中检测到了重组断点，B2 病毒的 5'UTR 与亚洲太平洋地区暴发期间分离的 B4 和 B3 株的相似度最高。在 genogroup C 分离株中未发现重组迹象。除了“86 B2 分离株”之外，荷兰分离株与同一亚组群的国际参考株在系统发生上交错分布，表明（重组）EV71 病毒在全球传播。在地方性和流行年份分离的 EV71 株的 5'UTR 中观察到的差异表明，5'UTR 的变化导致了能够引起暴发的株的进化。
