推断古老的分歧需要具有强大的遗传学信号的基因
Leonidas Salichos1, Antonis Rokas
1Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235, USA.
Nature
|May 10, 2013
概括
遗传学分析揭示了基因树的不一致性,挑战了标准方法. 选择具有高系遗传支持的基因对于准确重建进化历史至关重要.
科学领域:
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
- 生物信息学是一种生物信息学.
背景情况:
- 遗传学研究经常面临基因树之间的拓冲突 (不一致).
- 目前的方法,如连接和流类别的移除试图减轻不一致性.
- 遗传学推断的可靠性取决于解决基因树不一致的问题.
研究的目的:
- 调查不一致性对遗传学分析的影响.
- 评估共同实践在解决不一致性方面的有效性.
- 为了确定最优的战略,强大的遗传学重建.
主要方法:
- 从23个酵母基因组中对1070个正统基因组进行了基因组学分析.
- 推断的个体基因树和连接的基因谱.
- 评估不一致性严重程度和基因/内部节选择标准的影响.
主要成果:
- 鉴定了1070个不一致的基因树,与连接的基因谱相冲突.
- 不一致性随着更短的内部节点在基因结构中更深入而增加.
- 高平均内部节点支持显著改善了家族遗传推断的稳定性.
结论:
- 像连接这样的标准实践可能不足以准确地重建古代分歧.
- 选择具有强烈的遗传信号的基因是必不可少的.
- 证明没有显著的不一致性可以提高遗传学准确性.
相关概念视频
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In contrast, regions which code...
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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.
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