东欧亚地区多基因特征的方向选择和演化:古代DNA的洞察力
1Ulster Institute for Social Research, London, UK.
概括
古代基因组揭示了人类特征的进化趋势. 积极选择有利于智商和自闭症谱系障碍 (ASD) 等认知能力,而负面选择则对Holocene中的焦虑和抑郁产生了影响.
科学领域:
- 人口遗传学 人口遗传学
- 古遗传学是古遗传学的一部分.
- 人类进化人类进化
背景情况:
- 了解人类特征进化需要分析古代DNA和相关的表型.
- 东欧亚地区的人口为Holocene遗传适应提供了一个独特的窗口.
- 多基因分数 (PGS) 能够研究由许多基因影响的复杂特征.
研究的目的:
- 通过使用古代基因组,研究东欧亚人口中物理和心理社会现象的定向选择.
- 为了确定整个全新世纪遗传选择的时间趋势.
- 探索环境因素 (如度) 对特征进化的影响.
主要方法:
- 分析了1245个古老的欧亚基因组.
- 计算包括身高,教育程度 (EA),智商,自闭症谱系障碍 (ASD),精神分裂症,焦虑和抑郁症在内的特征的多基因分数 (PGS).
- 应用了结合混合物,地理和时间变量的回归模型.
- 使用斜线回归来分析与时间的非线性关系 (现在之前的年份).
主要成果:
- 在整个全新世纪中观察到显著的时间趋势.
- 对认知特征 (IQ,EA) 和自闭症谱系障碍 (ASD) 检测到的积极选择.
- 确定了焦虑和抑郁的负选择.
- 身高显示混合和非线性时间趋势.
- 度与ASD PGS,EA和身高有正相关,但与皮肤色素有负相关.
- 度对多种表型的非线性影响是显著的.
结论:
- 复杂的进化动态塑造了东欧亚地区人类的表型多样性.
- 气候介导的选择压力影响了特征进化,特别是在度方面.
- 不同的选择性压力在不同的时间尺度和环境中运行,导致不同的进化轨迹.
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