Admixture accelerated adaptation: signals from modern, ancient and archaic DNA.

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With the advent of new sequencing technologies, population geneticists now have access to more data than ever before. We have access to thousands of human genomes from a diverse set of populations around the globe, and, thanks to advances in DNA extraction and library preparation, we now are beginning to have access to ancient DNA sequence data. These data have greatly improved our knowledge of human history, human adaptation to different environments and human disease. Genome-wide studies have highlighted many genes or genomic loci that may play a role in adaptive or disease related phenotypes of biological importance. With these collections of modern and ancient sequence data we want to answer a key evolutionary question: how do human adaptations arise? We strongly believe that the state-of-the-art methodologies for uncovering signatures of adaptation are blind to potential modes of adaptation because they are lacking two critical components – more complete integration of multiple population haplotype data (including archaic, ancient and modern samples), and an account of population interactions that facilitate adaptation. Therefore I plan to develop new methods to detect shared selective events across populations by creating novel statistical summaries, and to detect admixture-facilitated adaptation which we believe is likely a common mode of natural selection. We will apply these tools to new datasets to characterize the interplay of natural selection, archaic and modern admixture in populations in the Americas and make a comparative analysis of modern and ancient European samples to understand the origin and changing profile of adaptive archaic alleles. As a result our work will reveal evolutionary processes that have played an important role in human evolution and disease.