Genetic variation, admixture and genome structure evolution through the lense of Drosophila genomics

在遗传模式生物中的研究是表征突变和 产生遗传和表型多样性的选择过程。特别是果蝇结合了 有效的群体取样，发达的实验技术，强大的基因组 工程方法，因此是一个独特的有价值的系统，用于表征的贡献， 遗传变异转化为表型变异和适合度变异。为了实现这一宏伟目标， 研究计划将利用D.黑胃系统： (1)增强果蝇基因组连接（DGN），这是一个广泛使用的数据库， 精心策划的高质量果蝇种群基因组变异数据集。具体来说，通过发展 这种方法包括已知的遗传变异，而不是映射到单个单倍体参考基因组， 研究计划将提高单核苷酸多态性的变异要求，并扩大我们的研究范围。 检测和准确表征结构变化的能力。同样，研究将开发和应用 用于精确描绘近交系基因组中杂合区域的方法。通过极大地 通过对数据库的完善，将对当前广泛使用的DGN进行新一轮的深入分析。 (2)揭示结构和连锁等位基因变异的适应性和基因表达后果 与自然染色体倒位有关。基因组工程技术使构建 在遗传同质性背景上具有受控断点的反转。通过对比， 自然发生的染色体倒位，研究将区分结构和连锁等位基因的影响 基因表达模式的变异。此外，研究将调查罚款的健身后果- 断点位置的尺度变化。染色质构象捕获测序，Hi-C，将使 产生测序文库，其大的插入物尺寸使得能够进行倒位断裂点作图。研究将 应用这种方法来映射罕见反转的断点。通过比较断点结构与 常见的倒位，这些数据将使我们能够直接了解产生倒位的突变力， 以及这些因素如何影响新染色体排列的自然选择。 (3)研究遗传差异的混合物的基因组和表型后果 亚群通过对几个D.研究将决定 基因-基因相互作用在驱动不同混合种群的自然选择中的相对重要性。 此外，通过利用来自一个混合群体的表型数据，该混合群体已用于许多研究， 关联研究，研究将评估混合物在塑造复杂表型长期的重要性 在最初的基因流事件之后，并开发本地祖先意识的方法来绘制复杂的性状 协会.

Studies in genetic model organisms are an indispensible mechanism for characterizing the mutational and selective processes that generate genetic and phenotypic diversity. In particular, Drosophila combines the advantages of efficient population sampling, well developed experimental techniques, with powerful genome engineering approaches and is therefore a uniquely valuable system for characterizing the contributions of genetic variation to phenotypic and fitness variation in natural populations. Towards this broad goal, this research program will leverage the D. melanogaster system to: (1) Enhance the Drosophila Genome Nexus (DGN), a widely used database that distributes a uniformly curated and high quality Drosophila population genomic variation dataset. Specifically, by developing methods that include known genetic variation rather than mapping to a single haploid reference genome, this research program will enhance both variation calls at single nucleotide polymorphisms as well as expand our ability to detect and accurately characterize structural variation. Similarly, research will develop and apply approaches for accurately delineating heterozygous regions in the genomes of inbred lines. By vastly improving the database, this reseach will enable a new wave of in-depth analyses of the widely-used DGN. (2) Reveal the fitness and gene expression consequences of the structural and linked allelic variation associated with natural chromosomal inversions. Genome engineering techniques enable the construction of inversions with controlled breakpoints on a genetically homogenous background. Through contrasts with naturally occurring chromosomal inversions, research will distinguish the impacts of structural and linked allelic variation on gene expression patterns. In addition, research will investigate the fitness consequences of fine- scale variation in breakpoint location. Chromatin conformation capture sequencing, Hi-C, will enable the production of sequencing libraries whose large insert sizes enable inversion breakpoint mapping. Research will apply this approach to map breakpoints of rare inversions. By comparing breakpoint structures with those of common inversions, these data will enable direct insights into the mutational forces that generate inversions as well as how these factors influence natural selection on new chromosomal arrangements. (3) Investigate the genomic and phenotypic consequences of admixture between genetically divergent subpopulations. By sequencing several admixed populations of D. melanogaster, research will determine the relative importance of gene-gene interactions in driving natural selection across diverse admixed populations. Furthermore, by leverage phenotypic data from one admixed population that has been used for a number of association studies, research will evaluate the importance of admixture in shaping complex phenotypes long after the initial gene flow event and develop local ancestry aware approaches for mapping complex trait associations.