MUC19基因:反复进化的进化历史和自然选择
Fernando A Villanea1, David Peede2,3,4, Eli J Kaufman5
1Department of Anthropology, University of Colorado, Boulder, CO, USA.
Science (New York, N.Y.)
|August 21, 2025
概括
在现代人类中发现的丹尼索瓦类的MUC19基因单体,显示出尼安德特人侵入的证据. 这种古老的基因变异在积极选择下, 在美国土著人口中存在高频率.
科学领域:
- 遗传学
- 古遗传学
- 人类的进化
背景情况:
- MUC19基因编码一种粘蛋白,这种糖蛋白对各种生物功能至关重要.
- 一些现代人类群体具有MUC19基因的丹尼索瓦类单体.
- 了解这些类型的起源和进化历史对于人类人口遗传学至关重要.
研究的目的:
- 在人类群体中调查丹尼索瓦类MUC19单元型的流行率和起源.
- 为了确定进化压力作用于这个单元型.
- 为了阐明MUC19单元型的内进源 (尼安德特人与丹尼索瓦人).
主要方法:
- 与丹尼索瓦类MUC19单元型相关的诊断变异的分析.
- 在混杂的美国人和古代土著美国人的频率评估.
- 在30个基对的重复中对副本数量的变化进行调查.
- 与尼安德特人和丹尼索瓦人的基因组进行比较分析.
主要成果:
- 类似于丹尼索瓦的MUC19类型在混合的美国人中常见,在混合之前的古代土著美国人中最常见.
- 这种类型是积极选择的,并且与特定的双重重复的副本数量增加有关.
- 在混合的美国人群中观察到这种重复的复制数量增加.
- 一些尼安德特人中存在类似丹尼索瓦人的MUC19单元型,这表明尼安德特人的内进.
结论:
- 类似于丹尼索瓦的MUC19类型可能是通过尼安德特人而不是丹尼索瓦人进入现代人类的.
- 积极的选择和增加的重复副本数量可能会带来适应性优势.
- 这一发现有助于我们了解古人类的混合及其对人类遗传多样性的影响.
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