阿根廷的兰巴达变种:分析SARS-CoV-2血统C.37的演变和传播
Mercedes Soledad Nabaes Jodar1,2, Carolina Torres2,3, Laura Mojsiejczuk3
1Laboratorio de Virologia, Hospital de Ninos Dr. Ricardo Gutierrez, Gallo 1330, Ciudad Autónoma de Buenos Aires 1425, Argentina.
Viruses
|June 28, 2023
概括
2021年初,SARS-CoV-2 Lambda变种在阿根廷出现,基因组监测显示了多次引入和本地传播. 这项研究追踪了它的传播和突变,强调了分子监测的重要性.
科学领域:
- 病毒学 病毒学
- 基因组学就是基因组学.
- 流行病学 流行病学
背景情况:
- 南美洲的第二波COVID-19受到玛和兰巴达变种的显著影响.
- 了解SARS-CoV-2变种的本地基因组流行病学对于公共卫生反应至关重要.
研究的目的:
- 描述阿根廷SARS-CoV-2 Lambda变种的出现,基因组多样性和传播动态.
- 确定Lambda变种在该国内的引入途径,本地传播和突变模式.
主要方法:
- 对来自阿根廷的9356个样本进行了分子监测 (2020年10月 - 2022年4月).
- 采用了测序,遗传学和遗传地理分析来重建变异的演变和传播.
- 进行了基因分析,以确定阿根廷兰巴达序列中的特定突变.
主要成果:
- 兰巴达变种于2021年1月首次在阿根廷检测到,在2021年4月达到顶峰.
- 据推断,至少有18个引入阿根廷,其中9个导致了本地传播.
- 时空重建表明,在布宜诺斯艾利斯开始多样化,然后在全国范围内扩散.
- 发现了罕见的突变,包括在免疫受损患者身上.
结论:
- 基因组监测有效地确定了阿根廷SARS-CoV-2 Lambda变种的引入和地理传播.
- 这项研究强调了监测病毒演变和新突变的出现的重要性.
- 这些发现有助于理解变种动态,并为针对SARS-CoV-2的策略提供信息.
相关概念视频
00:36Viral Mutations
32.5K
A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material...
32.5K
02:55The Evidence for Evolution
43.0K
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
43.0K
02:28Leaky Scanning
5.2K
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...
5.2K
02:05Gene Evolution - Fast or Slow?
7.2K
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
7.2K
01:05Single Nucleotide Polymorphisms-SNPs
15.3K
A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...
15.3K
02:02Cis-regulatory Sequences
10.0K
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
10.0K