Selection theory for marker-assisted backcrossing
Selection theory for marker-assisted backcrossing
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DOI：
10.1534/genetics.104.035451
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发表时间：
2005-06-01
期刊：
影响因子：
3.3
通讯作者：
Melchinger, AE
中科院分区：
文献类型：
--
作者：
Frisch, M;Melchinger, AE
标记辅助回交通常应用于基因渗入育种计划中。虽然选择理论是设计改善数量性状的育种计划的最重要工具，但没有可用于标记辅助回交的通用选择理论。在这篇论文中，我们开发了一种标记辅助选择理论，用于在回交程序中对源自轮回亲本的基因组比例进行选择，在目标基因预选后进行。我们的目标是（i）预测对选择的反应，以及（ii）给出选择最有希望的回交个体进行进一步回交或自交的标准。对选择反应的预测基于标记连锁图和回交群体亲本的标记基因型。与标准正态分布选择理论相比，我们的方法的主要优点是它考虑了由于选择而减少的供体基因组比例的方差。制定的选择标准考虑了候选者的标记基因型，并考虑这些是否将用于自交或回交。玉米和甜菜的模型基因组说明了对选择反应的预测。用甜菜的实验数据说明了有前途个体的选择。所提出的方法可以帮助遗传学家和育种者有效设计基因渗入程序。
Marker-assisted backcrossing is routinely applied in breeding programs for gene introgression. While selection theory is the most important tool for the design of breeding programs for improvement of quantitative characters, no general selection theory is available for marker-assisted backcrossing. In this treatise, we develop a theory for marker-assisted selection for the proportion of the genome originating from the recurrent parent in a backcross program, carried out after preselection for the target gene(s). Our objectives were to (i) predict response to selection and (ii) give criteria for selecting the most promising backcross individuals for further backcrossing or selfing. Prediction of response to selection is based on the marker linkage map and the marker genotype of the parent(s) of the backcross population. In comparison to standard normal distribution selection theory, the main advantage of our approach is that it considers the reduction of the variance in the donor genome proportion due to selection. The developed selection criteria take into account the marker genotype of the candidates and consider whether these will be used for selfing or backcrossing. Prediction of response to selection is illustrated for model genomes of maize and sugar beet. Selection of promising individuals is illustrated with experimental data from sugar beet. The presented approach can assist geneticists and breeders in the efficient design of gene introgression programs.