Frontiers seminar: "Identifying and dating historical admixture events and selection in Europeans"
- Date: –15:00
- Location: Evolutionsbiologiskt centrum Lindahlsalen
- Lecturer: Garrett Hellenthal, UCL, London
- Organiser: IOB
- Contact person: Carina Schlebush
Genetic data has proven to be a powerful resource to learn about human history. Here I focus on applying statistical models to genome-wide autosomal data in order to identify fine-scale population sub-structure, and to date admixture events where different groups intermixed within the past ~4,500 years (e.g. due to historical large-scale migrations). These methods exploit haplotype information, i.e. correlations among neighbouring genetic markers, to improve inference over available software. I report a new joint analysis of over 6000 European individuals from Belgium, Denmark, Finland, France, Germany, Italy, Norway, Poland, Spain and Sweden. I demonstrate the fine-scale genetic structure across these regions, illustrating how genetic similarity (typically) correlates strongly with country borders. I apply a new computational tool fastGLOBETROTTER, which has increased efficiency and accuracy over the currently most powerful haplotype-based admixture technique, to detect admixture events in these European data. I report admixture signals dated to ~500-600CE in individuals within Belgium, France and Germany that involve sources related to present-day Africans. I also report admixture signals related to Siberian sources dated to earlier than 300CE in Finland, to ~700-900CE in Sweden, and to ~300-700CE in Norway. Finally I describe and apply a new computational tool to identify genetic loci subjected to selection in these populations while accounting for this recent admixture.