Geographic models of selective sweeps

描述(申请人提供)：进化基本上是一个空间过程，因为种群在当地杂交并适应他们的环境。这对我们如何理解种群内的遗传多样性模式有着深远的影响，特别是在我们开始从种群中获得大量遗传数据的情况下。这些过程的良好模型和预测对于理解我们所看到的模式是必要的，例如，通过允许我们识别潜在的适应特征的基因座，并将局部适应与其他过程区分开来。我将创建和研究地理上明确的选择模型，包括平行的选择性扫描(“软”扫描)、中性变异的“搭便车”和选定的等位基因，以及新描述的等位基因“冲浪”现象；并将在种群基因组数据集中分析它们预期的特征。这将开始填补现有种群遗传学理论中的一个主要空白，即相对较少的显式空间模型，甚至更少包含选择的模型。这样的工具不仅使我们能够更好地重建地理分布的物种(如我们自己)的适应历史，还将帮助我们更准确地识别响应选择压力的基因组基因座，从而找到与疾病反应和对当地条件的生理适应有关的基因座。我将通过建立在种群遗传学、概率、生态学和统计物理学的现有理论基础上，与经验研究人员的目标和问题密切对话来做到这一点。 公共卫生相关性：我将调查地理在自然选择形成的遗传模式中所起的作用。这不仅将使我们能够更好地重建像我们自己这样分布广泛的物种的进化史，而且还将有助于我们识别选择的基因组模式，其中将包括对疾病的反应和对当地条件的生理适应。随着我们开始从不同人群中获得大量的基因数据，这种地理理解是至关重要的。

DESCRIPTION (provided by applicant): Evolution is fundamentally a spatial process, as populations interbreed locally and adapt to their environments. This has profound implications for how we understand patterns of genetic diversity within populations, especially as we begin to obtain large amounts of genetic data from populations. Good models and predictions of these processes will be necessary to understand the pat- terns we see, for instance, by allowing us to identify loci underlying adaptive traits, and to distinguish local adaptation from other processes. I will create and study geographically explicit models of selection, incorporating parallel selective sweeps ("soft" sweeps), the "hitchhiking" of neutral variation along with a selected allele, and the newly-described phenomenon of allele "surfing"; and will analyze their expected signatures in population genomics datasets. This will begin to fill a major gap in existing population genetics theory, which has relatively few explicit spatial models, and even fewer that incorporate selection. Such tools will not only allow us to better reconstruct the history of adaptation in geographically distributed species such as our own, but will also help us to more precisely identify genomic loci responding to selection pressures, and so find loci involved in disease response and in physiological adaptation to local conditions. I will do this by building on existing theory from population genetics, probability, ecology, and statistical physics, in close conversation with the goals and problems of empirical researchers. PUBLIC HEALTH RELEVANCE: I will investigate the role that geography plays in the genetic patterns formed by natural selection. This will not only allow us to better reconstruct the evolutionary history of widely distributed species such as our own, but will also help us in identification of genomic patterns of selection, which will include responses to disease and physiological adaptation to local conditions. Such geographic understanding is vital as we begin to obtain large amounts of genetic data from across populations.