代基因年龄提供了关于负选择强度的有限信息
Vivaswat Shastry1, Jeremy J Berg2
1Committee on Genetics, Genomics and Systems Biology, University of Chicago, Chicago, IL 60637, USA.
Genetics
|December 19, 2024
概括
使用基因年龄数据估计适应性效应 (DFE) 的分布,当所有站点频谱 (SFS) 数据可用时,提供最小的改善. 然而,等位基因年龄对于用值SFS数据推断选择系数变得有价值.
科学领域:
- 人口遗传学 人口遗传学
- 进化生物学 进化生物学
- 基因组学就是基因组学.
背景情况:
- 描述新突变的适应性效应 (DFE) 的分布对于种群遗传学至关重要.
- 传统的DFE估计依赖于将观察到的地点频谱 (SFS) 与包含人口史的模型相匹配.
- 新的方法利用基因树和古代DNA提供有关突变频率轨迹的信息.
研究的目的:
- 评估基因基因年龄信息在推断健身效应 (DFE) 分布中的有用性.
- 开发一种数值方法来计算给定选择强度和人口历史的等位基因年龄分布.
- 评估异基因年龄结合如何影响选择系数估计的准确性.
主要方法:
- 开发了一种高效的数值方法,以计算在给定的样本频率下分离变异年龄的密度.
- 利用等位基因频率和年龄的联合分布来总结轨迹信息.
- 扩展了Poisson随机场方法,包括用于估计选择系数的频率-年龄联合分布.
主要成果:
- 负选择的等位基因的无条件年龄分布通过使用负选择的SFS重新权衡中性年龄分布来很好地近似.
- 在估计中包括已知的等位基因年龄在内,当观察到完整的SFS时,选择系数的精度只会得到很小的改进.
- 基因基因年龄为选择系数估计提供了实质性的信息,具有值SFS,特别是对于大选择系数.
结论:
- 代基因年龄提供了关于DFE的有限的额外信息,超出了当前频谱中存在的信息.
- 结合等位基因年龄的准确性收益取决于上下文,特别是在频率值下显著.
- 从哈普洛型数据和中性先验来估计年龄的不确定性可以减少或偏差使用等位基因年龄的好处.
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