评论"证据表明,人类对最近获得的调节功能进行了丰富的净化选择"
1Genome Sciences Department, University of Washington, Seattle, WA 98195, USA. phg@uw.edu
Science (New York, N.Y.)
|May 11, 2013
概括
在非哺乳动物保护区的人类遗传变异不是由于净化选择. 我们的分析表明,突变变异性和技术工件解释了观察到的多形态模式,挑战了以前的解释.
科学领域:
- 基因组学就是基因组学.
- 人口遗传学 人口遗传学
- 分子进化分子进化
背景情况:
- 以前的研究表明,特定于血统的净化选择在非哺乳动物保存的基因组区域中塑造了人类的多态性.
- 这种解释是基于与对照组相比,在这些区域观察到的改变多态模式.
研究的目的:
- 在非哺乳动物保护的基因组区域重新评估人类多态模式的解释.
- 确定观察到的多态化趋势的主要驱动因素,特别是区分选择和其他因素.
主要方法:
- 从沃德和凯利斯 (2012) 的现有多态数据的重新分析.
- 与突变率和潜在的技术工件相关的多态化趋势的统计检查.
- 结果与原始研究关于净化选择的结论进行比较.
主要成果:
- 观察到的多形态趋势主要由突变变异性解释.
- 基因组数据中的技术工件也对观察到的模式做出了重大贡献.
- 在这些地区,血统特异性净化选择的影响似乎很小或完全不存在.
结论:
- 在非哺乳动物保护区中,净化选择驱动多态性的原始解释没有得到更密切的数据检查的支持.
- 突变过程和实验文物是这些基因组领域人类遗传变异的主要决定因素.
- 这种重新评估需要对人类基因组中对非哺乳动物保存元素起作用的进化力量进行修订理解.
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