Polygenic mutation in Drosophila melanogaster: estimates from response to selection of inbred strains.
Polygenic mutation in Drosophila melanogaster: estimates from response to selection of inbred strains.
复制标题
果蝇的多基因突变：对近交系选择反应的估计。
DOI：
10.1093/genetics/136.3.937
复制
发表时间：
1994
期刊：
影响因子：
3.3
通讯作者：
Nuzhdin,SV
中科院分区：
文献类型：
--
作者：
Mackay,TF;Fry,JD;Lyman,RF;Nuzhdin,SV
重复发散人工选择的腹部和sternopaly刚毛数量从一个高度近交系的果蝇，导致12.0腹部和8.2 sternopaly刚毛从影响刚毛数量的新突变的积累125代后的平均分歧。选择的反应是高度不对称的，更大的反应，低腹部和高sternopallic刚毛数量。VM的估计值，每代产生的突变方差，基于无穷小模型和平均的前25代的选择的反应，为4.32 × 10（-3）VE腹部刚毛数量和3.66 × 10（-3）VE胸侧刚毛数量，其中VE是环境方差。从第93代开始进行10个世代的系内分歧选择，腹鬃数的VM为6.75 × 10 ~（-3）VE，胸肋鬃数的VM为5.31 × 10 ~（-3）VE。然而，估计VM使用整个125代选择的响应较低，一般不适合无穷小模型，主要是因为观察到的减速响应不兼容的预测随着时间的推移增加的遗传方差。这些减速的反应，在人工选择的相反方向的反应期间，和反向选择的快速反应都表明影响猪鬃数量的新突变平均对健身有有害影响。通常观察到的加速反应，然后长时间的停滞期表明突变效应的刚毛的尖峰分布。
Replicated divergent artificial selection for abdominal and sternopleural bristle number from a highly inbred strain of Drosophila melanogaster resulted in an average divergence after 125 generations of selection of 12.0 abdominal and 8.2 sternopleural bristles from the accumulation of new mutations affecting bristle number. Responses to selection were highly asymmetrical, with greater responses for low abdominal and high sternopleural bristle numbers. Estimates of VM, the mutational variance arising per generation, based on the infinitesimal model and averaged over the responses to the first 25 generations of selection, were 4.32 x 10(-3) VE for abdominal bristle number and 3.66 x 10(-3) VE for sternopleural bristle number, where VE is the environmental variance. Based on 10 generations of divergent selection within lines from generation 93, VM for abdominal bristle number was 6.75 x 10(-3) VE and for sternopleural bristle number was 5.31 x 10(-3) VE. However, estimates of VM using the entire 125 generations of response to selection were lower and generally did not fit the infinitesimal model largely because the observed decelerating responses were not compatible with the predicted increasing genetic variance over time. These decelerating responses, periods of response in the opposite direction to artificial selection, and rapid responses to reverse selection all suggest new mutations affecting bristle number on average have deleterious effects on fitness. Commonly observed periods of accelerated responses followed by long periods of stasis suggest a leptokurtic distribution of mutational effects for bristles.