人类学. 人类学. 评论"晚期普莱斯托时代的人类骨架和mtDNA链接古美洲人和现代美洲原住民"
1Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany. pruefer@eva.mpg.de mmeyer@eva.mpg.de.
概括
古代DNA分析挑战了在墨西哥洞穴中发现的人类DNA的年龄. 研究人员发现没有证据表明线粒体DNA序列是古老的,质疑以前的发现.
科学领域:
- 古遗传学 古遗传学
- 分子人类学分子人类学
- 考古遗传学 考古遗传学
背景情况:
- 在墨西哥尤卡坦半岛的一个水下洞穴中发现了一颗1万2千到1万3千年前的人类牙.
- 聊天者和其他人. 据报道,从这颗牙中提取了DNA序列,提出它属于D1.1哈普洛组的古代人类.
研究的目的:
- 重新评估由Chatters等人报告的DNA序列的年龄.
- 为了研究古代人类牙中发现的线粒体DNA (mtDNA) 的起源.
主要方法:
- 对死后DNA损伤模式的分析.
- 对DNA序列特征进行比较分析.
主要成果:
- 没有发现任何证据来支持提取的DNA序列的古代起源.
- 观察到的损伤模式与12,000至13,000年前样本的序列不一致.
结论:
- 查特斯等人报告的DNA序列. 它们不太可能来自于古代人类.
- 需要进一步调查以确定这些DNA序列的真实起源和年龄.
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