Researchers based at SFI FutureNeuro Centre at RCSI and in collaboration with the Genealogical Society of Ireland and Sequence Bioinformatics Inc. Canada, recently reported on a study investigating the genetic legacy of Irish and English settlers in Newfoundland, Canada. The study investigated the British and Irish ancestry found in the Canadian population of Newfoundland, where genealogical records suggest a substantial migration of Irish fishermen in the 1700s and 1800s and subsequent isolation in the north-west Atlantic. Led by FutureNeuro researchers, the study used the Irish DNA Atlas and other Irish and British ancestry references, to find substantial genetic links between Newfoundland, and Ireland and England. These links suggest the communities within Newfoundland descend mainly from either South-Western English (Protestant) or South-Eastern Irish (Catholic) migrants.
Even today this ancestry is echoed in different regions of Newfoundland, where Irish ancestry is highest particularly in the Avalon Peninsula to the south-west of the island. This Irish ancestry is still strongly associated with Catholic backgrounds, with researchers finding evidence that Protestant-Catholic religious difference was one reason for the genetic isolation of communities in Newfoundland. By comparing the sort of genomes in Newfoundland to those in Ireland and Britain, the project also demonstrated the genetic legacy of the European settlement in Newfoundland, where modern Newfoundlanders are descended from a population bottleneck dated to around 300 years ago, aligning with migration records from the time.
This research highlights a unique history of the population, whereby potentially multiple founder events have occurred – leading to a mosaic of communities around the coastline of Newfoundland. This genetic history of isolation may explain higher frequencies of genetic variation leading to health conditions that are known in Newfoundland. It also provides a portrait of communities that can aid mapping specific health conditions and diseases to specific regions of the genome.
Read the full publication here in Communications Biology.