Wright A J, Cockerham C C
Genetics. 1985 Mar;109(3):585-97. doi: 10.1093/genetics/109.3.585.
The expected responses to mass selection carried out before or after reproduction in a population whose members all have a fixed probability of self pollination (s) are formulated using covariances of relatives and their component quadratic functions for a model with arbitrary additive and dominance effects. The response measured in the first generation offspring after selection (immediate gain) can differ from that retained when the population has regained equilibrium (permanent gain). The population mean behaves in a predictable manner during the return to equilibrium, and its value at any time can be predicted from earlier generations. The permanent gain from selection after reproduction is always (1 + s)/2 times as large as that from selection before reproduction, but the relationship of the immediate gains depends on the genetic model assumed. Numerical analysis applied to a model with two alleles per locus and varying allele frequencies, dominance ratios and numbers of loci showed that the proportion of the immediate gain retained at equilibrium was reduced with the large inbreeding depression associated with increasing dominance levels and numbers of loci and was generally lower for selection after reproduction than before. In the absence of information as to the magnitude of genetic variances and inbreeding depression in species reproducing by partial selfing, the importance of this phenomenon is unknown.
对于一个其成员都有固定自花授粉概率（s）的群体，在繁殖前或繁殖后进行群体选择的预期反应，是利用亲属协方差及其组成二次函数，针对具有任意加性和显性效应的模型来制定的。在选择后的第一代后代中测量的反应（即时增益）可能与群体恢复平衡时保留的反应（永久增益）不同。在恢复平衡的过程中，群体均值以可预测的方式变化，其在任何时候的值都可以根据早期世代来预测。繁殖后选择的永久增益总是繁殖前选择的永久增益的(1 + s)/2倍，但即时增益的关系取决于所假设的遗传模型。对每个位点有两个等位基因且等位基因频率、显性比率和位点数量不同的模型进行数值分析表明，随着与显性水平和位点数量增加相关的较大近交衰退，平衡时保留的即时增益比例会降低，并且繁殖后选择的即时增益通常比繁殖前更低。在通过部分自交繁殖的物种中，若缺乏关于遗传方差大小和近交衰退的信息，这种现象的重要性尚不清楚。
