相关实验视频
Updated: Jul 3, 2025
08:57
Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
15.9K
没有标记的进化树的统计总结
Rajanala Samyak1, Julia A Palacios1
1Department of Statistics, Stanford University, 390 Jane Stanford Way, Stanford, California 94305, U.S.A.
Biometrika
|February 14, 2024
概括
这项研究引入了新方法来总结和分析未标记的家族遗传树,提高对进化关系和层次数据的理解. 这些技术为复杂的树结构提供了可靠的统计总结,有助于各种科学应用.
科学领域:
- 人类遗传学 是一个学科.
- 计算生物学 计算生物学
- 进化生物学 进化生物学
背景情况:
- 遗传学树模型等级数据和进化关系.
- 总结和评估树木分布的不确定性,特别是未标记的树木,仍然是一个挑战.
- 未标记的树木对于比较来自不同方法或数据集的树样本越来越重要.
研究的目的:
- 定义和计算未标记的排列树和家谱的统计总结 (Fréchet平均值,差异,四分位数集).
- 开发有效的算法来计算这些摘要.
- 为了证明这些摘要在分析树分布和比较SARS-CoV-2进化树的有用性.
主要方法:
- 利用最近提出的距离指标用于未标记的排名二进制树和家谱.
- 定义Fréchet平均值,方差和四分位数间集合作为总结统计数据.
- 开发了一种高效的组合优化算法,用于计算弗雷切平均值.
主要成果:
- 成功定义并计算了未标记的排列树分布的统计总结.
- 证明了这些摘要对于流行的树分布的适用性.
- 在COVID-19疫情期间,应用了比较SARS-CoV-2进化树在不同地点的方法.
结论:
- 拟议的基于Fréchet的摘要为分析未标记的家族遗传树提供了有效的工具.
- 开发的算法可以有效计算这些摘要.
- 这些方法增强了进化关系和层次数据的研究,在流行病学中有实际应用.
相关概念视频
02:54Evolutionary Relationships through Genome Comparisons
5.7K
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
5.7K
03:21Phylogenetic Trees
45.3K
Phylogenetic trees come in many forms. It matters in which sequence the organisms are arranged from the bottom to the top of the tree, but the branches can rotate at their nodes without altering the information. The lines connecting individual nodes can be straight, angled, or even curved.
45.3K
01:23Phylogeny
44.1K
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire kingdom.
44.1K
02:05Gene Evolution - Fast or Slow?
7.1K
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...
7.1K
01:19Survival Tree
85
Survival trees are a non-parametric method used in survival analysis to model the relationship between a set of covariates and the time until an event of interest occurs, often referred to as the "time-to-event" or "survival time." This method is particularly useful when dealing with censored data, where the event has not occurred for some individuals by the end of the study period, or when the exact time of the event is unknown.
Building a Survival Tree
Constructing a...
Building a Survival Tree
Constructing a...
85
02:40The Tree of Life - Bacteria, Archaea, Eukaryotes
32.4K
The “tree of life” describes the evolution of life and the evolutionary relationships between organisms. The root of the tree is the common ancestor to all life on Earth. All other species radiate from this point, much like the branches of a tree. The numerous tips of these branches on the tree of life represent every living, or extant, species. Extinct species, which are species that no longer exist, can be found towards the center of the tree. Currently, these organisms, both...
32.4K