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FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
早期胎盘哺乳动物辐射的分辨率使用贝叶斯系遗传学
W J Murphy1, E Eizirik, S J O'Brien
1Laboratory of Genomic Diversity, National Cancer Institute, Frederick, MD 21702, USA.
概括
胎盘哺乳动物的基因学揭示了Afrotheria是最早的分离群体,起源于大约1.03亿年前. 这一发现有助于了解胎盘哺乳动物的早期生物地理历史.
科学领域:
- 进化生物学 进化生物学
- 分子遗传学分子遗传学
- 哺乳动物古生物学
背景情况:
- 胎盘哺乳动物的基因已被部分分为四个主要组.
- 完整的顺序间关系和根位置仍然不清楚.
- 了解早期的胎盘生物地理需要解决这些遗传学不确定性.
研究的目的:
- 通过分子数据研究胎盘哺乳动物的系系.
- 为了建立一个完整的层次关系.
- 确定根的位置和早期生物地理学的影响.
主要方法:
- 利用贝叶斯学和最大概率的遗传学方法.
- 采用了全面的16.4基基基的分子数据集.
- 分析了顺序间关系和分歧时间.
主要成果:
- 达到了几乎完全的解决跨序的关系.
- 确定了Afrotheria和其他胎盘动物之间的基底分裂.
- 约定这个基底分裂大约在1.03亿年前,可能与南美洲和非洲的白纪分离有关.
结论:
- 胎盘哺乳动物的根源可能在南半球 (Gondwana).
- 早期的Afrotheria分歧为哺乳动物生物地理史提供了关键的见解.
- 这项研究完善了我们对胎盘哺乳动物进化关系和古代分布的理解.
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