Hamilton Institute Seminar

Wednesday, October 4, 2023 - 13:00 to 14:00
Hamilton Institute Seminar room (317), 3rd Floor Eolas Building, North Campus

Virtual participation: Zoom details available here

Speaker: Dr Lara Cassidy, Trinity College Dublin

Title: "A genomic journey through Irish history"

Abstract: This talk focuses on the ancient genomics of Ireland and examines three features of past societies: migration, kinship and survival. These leave signatures on the genome, which can tell the story of a single individual or entire island. First, we characterize the ebb and flow of migration to Ireland, identifying periods of population continuity and turnover across millenia. We then ask how we can better appreciate the complexity in sharp demographic transitions through denser sampling and methodological improvement. Second, we leverage haplotypes to identify near and distant biological relatives. Kinship practices and group identities can shape patterns of genetic relatedness and inbreeding within and between communities, which will be explored through several case studies. Third, the health of populations and individuals is shaped by short and long-term interactions between genes and the environment. Ancient genomes allow us to chart the trajectories of important mutations and reveal the past selective pressures that have helped mould the population of the island today. 

Biography: Lara Cassidy is currently an assistant professor at Trinity College Dublin, where she completed her PhD in ancient human genomics in 2017 under the supervision of Dan Bradley. Her doctoral thesis established a working framework for the genetic history of northwest Europe and resolved longstanding questions on the origins of the modern Irish population. More recently, she has focussed on the inference of past social organisation in Ireland and Britain by utilising finescale patterns of relatedness and inbreeding. She is particularly interested in the emergence of social stratification and provided evidence for a hereditary elite in Irish passage tomb societies. Her team are also leveraging Ireland’s insularity and long-term genetic continuity to study the evolutionary forces that have shaped human health and disease.