自然发生的DNA多态度的水平与D. melanogaster的重组率相关
1Section of Genetics and Development, Cornell University, Ithaca, New York 14853-2703.
Nature
|April 9, 1992
概括
遗传重组率影响了Drosophila melanogaster中的核酸多样性. 更高的重组与增加的遗传变异相关,这表明基因组中有益突变的上车.
科学领域:
- 进化遗传学的进化遗传学
- 人口遗传学 人口遗传学
- 基因组学就是基因组学.
背景情况:
- 在Drosophila melanogaster中复合性较低的基因组区域显示核酸多样性减少.
- 这种现象与有利突变的车效应有关.
研究的目的:
- 研究Drosophila melanogaster基因组中的重组率和核酸多样性之间的相关性.
- 确定遗传上车是否是限制遗传变异的重要因素.
主要方法:
- 从Drosophila melanogaster的自然种群的20个基因区域中分析核酸多样性.
- 与核酸多样性和Drosophila melanogaster和Drosophila simulans之间DNA序列分歧的重组率的比较.
主要成果:
- 在Drosophila melanogaster的区域重组率和核酸多样性之间发现了正相关性.
- 没有观察到重组率和DNA序列分歧之间的相关性,排除突变率或功能约束作为主要驱动因素.
- 这些发现支持这样一个假设,即遗传上会显著影响遗传变异.
结论:
- 重组率是Drosophila melanogaster核酸多样性的一个主要决定因素.
- 与有利突变相关的遗传上车在多索菲拉基因组中广泛存在.
- 这一过程对自然种群中观察到的遗传变异水平起着显著的约束作用.
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