Quantifying Epistasis for Fitness in the Native Legume, Chamaecrista Fasciculata

9815780 Fenster&Amp；Zimmer本研究涉及导致簇毛决明种群间遗传差异的基因作用类型。基因之间的作用可能是相互独立的，因此遗传分化可能只是反映了选择作用于单个基因的累积效应。然而，生物之间的重要差异可能反映了对基因组合的选择，这意味着基因相互作用或上位性是重要的。基因作用的类型可以通过跟踪种群间杂交后代的存活和繁殖来确定。如果种群因为选择作用于基因组合而适应环境，那么来自不同种群的基因混合将导致有利的基因相互作用的中断，并降低杂交后代的生存和繁殖。这项研究将使用传统的生物测定技术和分子分析来量化负责种群适应环境的基因作用的性质。该项目对进化论、作物和动物育种以及保护生物学具有重要意义。如果生物因为基因之间的相互作用而适应环境，那么我们的进化模型将需要更加复杂。重要基因相互作用的检测将为我们提供一个与物种形成等宏观进化过程相当的微观进化过程。基因交互作用意味着，不同的育种策略可能会对作物和动物的改良产生更大的效果。维持或保护濒危物种遗传多样性的策略将受到基因相互作用是否决定与生存和繁殖相关的特征的影响。

9815780Fenster & Zimmer This research concerns the type of gene action responsible for genetic differences among populations of Chamaecrista fasciculata. Genes may act independently of one another so that genetic divergence may simply reflect the accumulated effects of selection acting on single genes. However, important differences among organisms may reflect selection on combinations of genes implying that gene interaction or epistasis is important. The type of gene action can be determined by following the survivorship and reproduction of progeny derived from crosses between populations. If populations are adapted to their environment because selection has acted on combinations of genes, then mixing genes from different populations will result in a disruption of favorable gene interactions and decreased survivorship and reproduction in the hybrid progeny. This study will use traditional biometrical techniques along with molecular analyses to quantify the nature of gene action responsible for adaptation of a population to its environment. This project has important implications for evolution, crop and animal breeding, and conservation biology. If organisms are adapted to their environment because of interactions among genes, then our models of evolution will need to be more complex. Detection of important gene interaction will provide us with a microevolutionary equivalent of macroevolutionary processes such as speciation. Gene interactions imply that different breeding strategies than those presently employed may have greater efficacy for crop and animal improvement. Strategies for maintaining or preserving genetic diversity in endangered species will be influenced by whether gene interaction determines traits associated with survivorship and reproduction.