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在哈布斯堡王朝内生对孕产妇死亡率和生育率的影响
Francisco C Ceballos1,2, Román Vilas1, Gonzalo Álvarez1
1Department of Zoology, Genetics and Physical Anthropology, University of Santiago de Compostela, Santiago de Compostela, Spain.
概括
亲生繁殖显著减少了哈布斯堡女人的寿命和增加了孕产妇死亡率,分娩间隔较长. 这项研究提供了第一个关于近亲繁殖的证据.
科学领域:
- 人类遗传学 人类遗传学
- 历史人口统计 历史人口统计
- 生殖生物学 生殖生物学
背景情况:
- 亲生繁殖,即相关个体的交配,可能会对后代的健康和生存产生不利影响.
- 哈布斯堡王朝是一个著名的欧洲王朝,几个世纪以来一直在进行广泛的近亲繁殖.
- 之前的研究表明,近亲繁殖对生殖前生存的负面影响.
研究的目的:
- 调查内生繁殖对哈布斯堡王朝长寿和生育能力的影响.
- 确定近亲繁殖是否影响了这一历史人口中的孕产妇死亡率和生殖成功.
主要方法:
- 分析了124个哈布斯堡王朝的婚姻 (1450-1800年) 使用来自8000多个人的家谱数据.
- 计算亲属关系和近亲繁殖系数.
- 包括回归,卡普兰-梅尔曲线,考克斯比例危险模型和零膨胀回归模型在内的统计分析.
主要成果:
- 在有孩子的妇女中,内生系数和死亡年龄之间发现了显著的负相关性.
- 亲生繁殖在分娩后四周内显著增加了孕产妇死亡风险 (危险比率=2.36).
- 更多的近亲女性经历了分娩之间的更长的间隔,这表明生育能力下降.
结论:
- 在哈布斯堡血统中,近亲繁殖对成年人的生存率和生殖健康产生了重大负面影响.
- 这项研究首次证实了近亲繁殖对人类孕产妇死亡率的有害影响.
- 虽然近亲繁殖影响了生育能力,但生殖补偿可能发生在不太生育的女性中.
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