SARS冠状病毒的基因组变异与进化研究

发布时间：2018-03-04 02:28

本文选题：SARS冠状病毒　切入点：基因组　出处：《浙江大学》2005年硕士论文　论文类型：学位论文

【摘要】：2003年3月,一种新的冠状病毒(CoV)—SARS冠状病毒被确认为引起SARS(severe acute respiratory syndrome)的病原。在本研究中,我们获取了10株直接来源SARS病人粪便或咽拭子样本及其细胞传代培养物的SARS-CoV全基因组序列,并会同公共数据库中的115株SARS-CoV基因组序列进行了系统地比较分析。以GZ02序列为参照,发现266个在2个以上基因组中同时存在的单核苷酸多态(SNP)位点。这些多态位点在 SARS-CoV基因组中呈偏态分布。同时发现了18种主要的缺失类型和2种主要的插入类型,定义了2种与发病时期及致死率相关的基因型。S蛋白在发病早期受到最大的正向选择压力,然后逐步稳定下来。我们应用邻位连接法(neighbor-joining)构建了125株 SARS-CoV的亲缘树。通过来源于同一病人的直接取样样本及其细胞传代培养物的 SARS-CoV基因组序列对比分析发现,在细胞培养过程中SARS-CoV基因组序列几乎不会产生突变,但取样时间策略将会影响这一过程。推测这种现象有可能是由于细胞传代培养过程会选择出某种优势株病毒造成的。
[Abstract]:In March 2003, a new coronavirus, CoV-SARS-CoV, was identified as causing SARS(severe. Acute respiratory syndrome. In this study, we obtained 10 direct source SARS patients. SARS-CoV genome sequence of fecal or pharyngeal swab samples and their cell passage cultures, and in conjunction with common data. The genomic sequences of 115 strains of SARS-CoV in the library were compared and analyzed systematically. There are 266 single nucleotide polymorphism (SNPs) loci in more than 2 genomes. In the SARS-CoV genome, 18 major deletion types and 2 major insertions were found. The two genotypes associated with the onset and mortality were defined as the most positive in the early stage of the disease. The selection pressure, and then gradually stabilized. We built 125 strains using the neighbor connection method (Nighbor-joining). A phylogenetic tree of SARS-CoV. Derived from a direct sample of the same patient and its cell passage culture. The comparative analysis of SARS-CoV genome sequence showed that the SARS-CoV genome sequence was almost in the process of cell culture. There is no mutation, but sampling time strategy will affect the process. It is assumed that this phenomenon may be due to cell transmission. Generation culture will result in the selection of a dominant strain of the virus.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2005
【分类号】：R373

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