净化和适应性选择对人类mtDNA区域变异的影响
Eduardo Ruiz-Pesini1, Dan Mishmar, Martin Brandon
1Center for Molecular and Mitochondrial Medicine and Genetics, University of California, Irvine, CA 92697-3940, USA.
概括
人类线粒体DNA (mtDNA) 突变的保护性随着度的增加而增加,有助于适应更寒冷的气候. 这些古老的遗传变异影响现代健康,影响能量和寿命.
科学领域:
- 人类进化遗传学人类进化遗传学
- 线粒体DNA (mtDNA) 分析分析
- 人口基因组学是人口的基因组学.
背景情况:
- 人类线粒体DNA (mtDNA) 含有对进化适应至关重要的遗传变异.
- 了解mtDNA突变的地理分布和功能影响是人类进化研究的关键.
研究的目的:
- 重建全球人类mtDNA序列中核酸替代的遗传顺序.
- 为了研究mtDNA突变特征 (频率,氨基酸保存) 和地理度之间的关系.
- 探索与度相关的mtDNA变体与人类健康结果 (能量缺乏症疾病,长寿) 之间的潜在联系.
主要方法:
- 对1125个全球人类线粒体DNA (mtDNA) 序列的遗传学分析.
- 核酸替代的排序基于它们的进化发生.
- 评估内部分支替代突变的相对频率和氨基酸保存.
主要成果:
- 从热带非洲到更高度 (温带欧洲,北极东北西伯利亚) 观察到mtDNA突变的频率和氨基酸保存的明显增加.
- 在高度地区普遍存在的mtDNA谱系的起源上发现了高度保存的氨基酸替代.
- 发现这些高度mtDNA谱系与增加对能量缺乏症疾病的易感性和延长寿命相关.
结论:
- 特定的mtDNA替代突变促进了人类适应更冷,更高度的环境.
- 这些适应型mtDNA变异继续影响当代人群中的人类健康,影响疾病风险和寿命.
- 这项研究强调了线粒体DNA编码的进化适应对人类生理和健康的持久影响.
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