台灣諾若病毒重組株之全長基因體序列分析

Sequence analysis of full-length genome of norovirus recombinants in Taiwan

莎日娜(Sarnai.Naran)

指導教授 ： 李君男

國立臺灣大學/醫學院/醫學檢驗暨生物技術學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.10574

摘要

人類諾若病毒(Norovirus)於人類各年齡層均會引起腸胃炎，主要經由受糞便汙染之水及食物所傳染，其次為人與人之間的傳染。每年各地的大流行會造成嚴重的發病率及死亡率，此種情形在開發中國家特別顯著。近年來，於世界各地已有一些研究指出諾若病毒會發生自然的基因重組現象。由於諾若病毒發生基因重組比想像中頻繁，因此更進一步瞭解諾若病毒之基因多重組及多樣性對於醫療保健上有很大的幫助。
本論文研究分析台灣2002、2003及2006年之糞便檢體中所分離之九株重組病毒株之全長基因。結果有八個病毒株分別可得到包含病毒全長基因之三段PCR片段；核酸序列分析後經由種系分析可知在各不同基因不同諾若病毒之間的關係。由SimPlot軟體分析可得知諾若病毒重組發生之位點。針對聚合酶基因進行種系分析，結果發現Taipei/0212/2003/TW、Taipei/2339/2002/TW、Taipei/0089/2003/TW、Taipei/0510/2002/TW、Taipei/1969/2002/TW屬GIIb基因型。此外針對外殼蛋白質基因進行種系分析，得知此五種分屬兩種不同基因型--Taipei/0089/2003/TW、Taipei/0510/2002/TW、Taipei/1969/2002/TW及Taipei/0212/2003/TW屬GII/3基因型；Taipei/2339/2002/TW屬GII/2基因型。另三個病毒株--Taipei/0760/2002/TW、Taipei/1047/2006/TW及Taipei/0898/2006/TW之聚合酶基因之種系分析屬GII/12及GII/10基因型，基因相似度達98%；外殼蛋白質基因之種系分析則發現Taipei/0760/2002/TW、Taipei/1047/2006/TW及Taipei/0898/2006/TW分屬GII/10、GII/12、GII/4三種基因型。
綜合以上結果顯示，台灣確實存在諾若病毒之基因重組病毒株，此為第一次證明自然產生之重組諾若病毒確實曾在台灣造成感染。

關鍵字

台灣 ； 諾若病毒 ； 李君男 ； 重組株之 ； 莎日娜 ； 序列分析

並列摘要

Human norovirus (NoV) causes gastroenteritis in humans in all age groups. NoV is transmitted through fecal contamination of food and water, and secondary person-to-person spread is common. Annual epidemics cause severe morbidity and even mortality, especially in developing countries. In recent years several naturally occurring recombinant NoVs have been reported around the world. Considering the fact that recombination occur much more often than it was thought to be, further study of the diversity and ongoing recombination of NoV may bring tremendous assistance for epidemiological studies and more importantly bring medical and healthcare attention for diminishing worldwide epidemics.
In this study the full-length genome of nine norovirus recombinants, isolated from stool specimens from 2002, 2003, and 2006 in Taiwan. Three PCR fragments covering the full-length genome were obtained for eight of the isolates. After the nucleotide sequences were determined, the relationships among different noroviruses (NoVs) in different genes were studied by phylogenetic analysis. The recombination break points were revealed by SimPlot analysis. According to the polymerase gene-based phylogenetic analysis, five isolates Taipei/0212/2003/TW, Taipei/2339/2002/TW, Taipei/0089/2003/TW, Taipei/0510/2002/TW, and Taipei/1969/2002/TW belonged to the recombinants with the GIIb polymerase gene. By capsid gene-based phylogenetic analysis, the above described GIIb polymerase recombinants clustered onto two distinct genotypes, Taipei/0089/2003/TW Taipei/0510/2002/TW, Taipei/1969/2002/TW, and Taipei/0212/2003/TW clustered with GII/3 strains, Taipei/2339/2002/TW clustered with GII/2 strains. Three isolates Taipei/0760/2002/TW, Taipei/1047/2006/TW, and Taipei/0898/2006/TW, clustered with GII/12 and GII/10 strains and shared 98% identity in polymerase gene. According to the capsid gene-based analysis, Taipei/0760/2002/TW, Taipei/1047/2006/TW, and Taipei/0898/2006/TW clustered with GII/10, GII/12, and GII/4 strains, respectively. Taken together, these results confirmed the existence of naturally occurring recombinant NoVs in Taiwan and this is the first evidence of naturally occurring recombinant NoV infection in Taiwan.

並列關鍵字

taiwan ； Norovirus ； Chun-Nan Lee ； recombinant ； Sarnai.Naran ； sequence analysis

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