The effects of spontaneous mutation on quantitative traits. I. Variances and covariances of life history traits.
The effects of spontaneous mutation on quantitative traits. I. Variances and covariances of life history traits.
复制标题
自发突变对数量性状的影响。
DOI：
10.1093/genetics/138.3.773
复制
发表时间：
1994
期刊：
影响因子：
3.3
通讯作者：
Charlesworth,B
中科院分区：
文献类型：
--
作者：
Houle,D;Hughes,KA;Hoffmaster,DK;Ihara,J;Assimacopoulos,S;Canada,D;Charlesworth,B
在没有自然选择的情况下，我们通过将一个高适合度的第二条染色体的200个杂合复制回交到一个平衡种群44代，积累了果蝇的自发突变。在积累的第33代和第44代，我们提取了染色体样本，并分析了它们在成年前期和后期的雌性繁殖力、雄性和雌性寿命、成年前期和后期的雄性交配能力、生产力(繁殖倍数)和体重方面的纯合子表现。除雄株交配力和体重外，其余性状的品系间变异均显著增加。当相对于性状平均值计算时，方差增加的速度与以前关于卵到成虫存活率的研究中发现的相似。各性状间的突变相关均为强正相关。许多相关性与0显著不同，但没有一个相关性与1显著不同。这些数据表明，突变-积累假说不能充分解释黑腹蛇衰老的进化。突变-选择平衡似乎足以解释繁殖力和寿命的相当大比例的加性遗传差异。
We have accumulated spontaneous mutations in the absence of natural selection in Drosophila melanogaster by backcrossing 200 heterozygous replicates of a single high fitness second chromosome to a balancer stock for 44 generations. At generations 33 and 44 of accumulation, we extracted samples of chromosomes and assayed their homozygous performance for female fecundity early and late in adult life, male and female longevity, male mating ability early and late in adult life, productivity (a measure of fecundity times viability) and body weight. The variance among lines increased significantly for all traits except male mating ability and weight. The rate of increase in variance was similar to that found in previous studies of egg-to-adult viability, when calculated relative to trait means. The mutational correlations among traits were all strongly positive. Many correlations were significantly different from 0, while none was significantly different from 1. These data suggest that the mutation-accumulation hypothesis is not a sufficient explanation for the evolution of senescence in D. melanogaster. Mutation-selection balance does seem adequate to explain a substantial proportion of the additive genetic variance for fecundity and longevity.