罕见的编码变异的进化和功能影响,来自人类外体的深度测序
Jacob A Tennessen1, Abigail W Bigham, Timothy D O'Connor
1Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA.
概括
这项研究对人类基因进行了测序,以发现与复杂疾病相关的罕见遗传变异. 大多数已识别的变异是罕见的,以前未知的,并且是特定于人群的,这突显了在遗传研究中需要大样本的大小的需要.
科学领域:
- 遗传学 是一个遗传学.
- 基因组学就是基因组学.
- 人口遗传学 人口遗传学
背景情况:
- 了解罕见遗传变异在复杂疾病中的作用至关重要.
- 之前的研究在识别不同种群中罕见变异的范围有限.
研究的目的:
- 为了研究蛋白质编码基因中罕见的单核酸变体 (SNVs) 的景观.
- 评估这些SNV在欧洲和非洲血统的人群中的频率和功能影响.
- 为未来关于复杂疾病遗传结构的研究提供信息.
主要方法:
- 在2440个个体中对15585个人类蛋白质编码基因进行全基因组测序.
- 变体调用和注释以识别SNV.
- 分析变异频率,新性,种群特异性和预测的功能影响.
主要成果:
- 确定了超过50万个SNV,其中86%是罕见的 (MAF<0.5%).
- 82%的鉴定SNV是以前未知的,并且是特定于人群的.
- 预计每个人携带的SNV约有2.3%会影响蛋白质功能,其中95.7%是罕见的.
- 由于最近的人口增长和较弱的净化选择,罕见的功能变异过多.
结论:
- 罕见的变异是丰富的,经常具有功能意义,对复杂的疾病关联研究构成挑战.
- 较大的样本大小对于稳定地将罕见变异与复杂特征联系起来至关重要.
- 这项研究为未来对复杂疾病的遗传研究提供了基础数据集.
相关概念视频
Gene Evolution - Fast or Slow?
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...
Gene Evolution - Fast or Slow?
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...
Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Multi-species Conserved Sequences
Next-generation sequencing technologies have created large genomic databases of a variety of animals and plants. Ever since the human genome project was completed, scientists studied the genome of primates, mammals, and other phylogenetically distant living beings. Such large-scale studies have provided new insights into the evolutionary relationship between organisms.
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Evolutionary Relationships through Genome Comparisons
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...
Comparing Copy Number Variations and SNPs
Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist within a population. These variations can be a single nucleotide or a larger chromosomal variation.
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...


