重建安达曼群岛居民的起源
Kumarasamy Thangaraj1, Gyaneshwer Chaubey, Toomas Kivisild
1Centre for Cellular and Molecular Biology, Hyderabad-500 007, India.
Science (New York, N.Y.)
|May 14, 2005
概括
安达曼"尼格里托"和尼科巴尔"蒙古尔"种群.
科学领域:
- 人类进化遗传学人类进化遗传学
- 人口遗传学 人口遗传学
- 古代DNA分析 古代DNA分析
背景情况:
- 安达曼和尼科巴尔群岛居民的起源在历史上是模两可的.
- 之前的研究对这些孤立社区的遗传谱系提供了有限的见解.
研究的目的:
- 调查安达曼"黑人"和尼科巴尔"蒙古族"人口的深远祖先起源.
- 阐明这些岛屿群岛的迁移模式和遗传隔离.
主要方法:
- 分析了来自安达曼 (Onge,大安达曼) 和尼科巴尔群岛个体的完整线粒体DNA (mtDNA) 序列.
- 遗传学分析以确定根深蒂固的群体和共同的祖先.
- 将mtDNA谱系与全球人口进行比较,以推断迁移历史.
主要成果:
- 在安达曼群体中发现了两个截然不同的,深度分支的mtDNA分支,起源于创始人哈普洛组M.
- 这些安达曼群岛的克莱德与在印度,非洲,东亚,新几内亚和澳大利亚发现的血统有联系.
- 尼科巴岛的mtDNA序列显示,尼科巴岛人与来自东南亚的人口有密切的遗传亲缘关系.
结论:
- 安达曼的mtDNA血统表明,自从解剖学上现代人类的早期"非洲外"迁移以来,他们一直在遗传隔离中生存.
- 遗传数据支持尼科巴尔人的独特祖先历史,与东南亚人口密切相关.
- 线粒体DNA分析为安达曼和尼科巴尔群岛的人口提供了关键的见解.
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