由于在两个猪种群中进行选择而导致的等位基因频率和遗传结构的变化
Yvonne C J Wientjes1, Katrijn Peeters2, Piter Bijma3
1Animal Breeding and Genomics, Wageningen University & Research, 6700 AH, Wageningen, The Netherlands. yvonne.wientjes@wur.nl.
Genetics, selection, evolution : GSE
|December 17, 2024
概括
遗传选择的目的是增加有利的等位基因. 这项研究发现,在猪的广泛指数上的选择会在整个基因组中传播效应,限制大等位基因频率变化,并显示与全基因组关联研究意义的最小相关性.
科学领域:
- 动物遗传学动物遗传学
- 量化遗传学 量化遗传学
- 基因组选择 基因组选择
背景情况:
- 遗传选择增加了有利的等位基因频率,需要对长期影响进行监测.
- 了解等位基频率动态对于评估选择疗效至关重要.
研究的目的:
- 调查正在选择的两种猪系中的等位基因频率变化.
- 检查代基因频率转移与全基因组关联研究 (GWAS) 结果之间的关系.
- 评估随着时间的推移选择对遗传架构的影响.
主要方法:
- 分析2015-2021年两种母猪系的基因型和表型.
- 观察到的等位基因频率变化与漂移模拟 (基因掉落) 的比较.
- 对正在选择的特征和选择指数进行全基因组关联研究 (GWAS).
主要成果:
- 观察到显著的等位基因频率变化,平均变化超过漂移预期.
- 对于选定的特征,GWAS确定了显著的区域,但这些特征并没有与具有很大基因基因频率变化的区域重叠.
- 对于广选择指数没有发现任何重要的GWAS区域,这表明多基因控制.
- Pleitotropic 和对抗性遗传关联是常见的,减少了对特定区域的选择压力.
- 曼哈顿的地图显示,随着时间的推移,变化很小,这表明基因结构稳定.
结论:
- 显著的GWAS区域和主要的等位基因频率变化之间没有发现直接联系.
- 大量的等位基因频率变化通常归因于遗传漂移而不是直接选择.
- 在广泛的索引上进行选择将选择压力分布在全基因组范围内,限制了实质性的等位基因频率转移.
- 该研究强调,广泛的指数可能会掩盖特定位置的直接选择信号.
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