人类氨基酶位点的重建揭示了古老的重复种植现代变异
Feyza Yilmaz1, Charikleia Karageorgiou2, Kwondo Kim1
1The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA.
Science (New York, N.Y.)
|October 17, 2024
概括
人体唾液氨酶基因 (AMY1) 副本数量有所不同,更多的副本与富含粉的饮食有关. 古代DNA揭示了一个常见的三副本AMY1单元型存在于80万年前,欧洲农民的副本数量正在增加.
科学领域:
- 人类进化遗传学
- 分子人类学
- 种群遗传学
背景情况:
- 人体唾液氨酶基因 (AMY1) 拷贝数与饮食中粉的摄入量有关.
- 对AMY1的进化分析而言,准确的类型变异地图至关重要.
- 之前的研究缺乏序列解析的单元型数据,以获得全面的进化见解.
研究的目的:
- 为人类的AMY1基因创建核酸分辨率的单质变异地图.
- 调查AMY1拷贝数变化的进化史和选择压力.
- 探索 AMY1 副本数量在人类适应饮食中的作用.
主要方法:
- 在98个个体中确定了30个不同的AMY1单元类型.
- 在负选择下编码序列演变的分析.
- 在古人类和古人类基因组中对单元类型的基因组分析.
- 在AMY1基因重组中研究非等位基因同类重组.
- 古代欧洲农民群体中AMY1副本数变化的频率分析.
主要成果:
- 鉴定了具有核酸分辨率的 30 种结构上不同的 AMY1 类型.
- AMY1编码序列在负选择下演变.
- 一个常见的三副 AMY1 单质原型至少起源于 800,000 年前.
- 反复的非基因同类重组驱动AMY1复制数的重新排列.
- 在过去的4000年中,欧洲农民中AMY1复制数扩增的频率增加.
结论:
- AMY1基因具有深厚的进化历史,至少可以追溯到80万年前.
- 欧洲农民的AMY1拷贝数量扩大可能代表了对食粉增加的适应反应.
- 了解AMY1单元型变异为人类适应饮食变化提供了关键的见解.
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