人类类的高基因组有害突变率
1Centre for the Study of Evolution and School of Biological Sciences, University of Sussex, Brighton, UK. A.C.Eyre-Walker@susx.ac.uk
Nature
|February 9, 1999
概括
人类经历了新有害突变的高率,每代每基因组超过1.6个影响蛋白质编码序列. 自然选择消除了许多,但这种速度使生殖率较低的物种变种.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 分子生物学分子生物学
背景情况:
- 人类基因组突变率受到争议.
- 了解有害突变的积累对于进化研究至关重要.
研究的目的:
- 为了估计人类类动物的有害突变率.
- 评估自然选择对这些突变的影响.
主要方法:
- 应用了使用DNA序列分析的分子方法.
- 检查了人类蛋白质编码序列中选择性约束的水平.
主要成果:
- 估计在人类血统中,每代每位双胞胎有4.2个氨基酸改变突变.
- 确定至少38%的这些突变被自然选择消除.
- 计算了每一代二倍体基因组的1.6多个新的有害突变.
结论:
- 蛋白质编码序列中的有害突变率接近人类可容忍的极限.
- 有害突变的协同效应可能会发生.
- 人类类的非典型的低选择性约束表明,稍微有害的突变的固定.
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