NEW YORK – By tapping into haplotype patterns present in UK Biobank participants, a research team from Ireland has untangled some of the recent genetic relationships and differentiation events between populations in Europe.
"In addition to building and expanding upon previous knowledge in Europe, our results show the UKBB as a source of diverse ancestries beyond Britain," first and corresponding author Edmund Gilbert, a pharmacy and biomolecular sciences researcher with the Royal College of Surgeons, and his colleagues wrote. "These worldwide ancestries sampled in the UKBB may complement and inform researchers interested in specific communities or regions not limited to Britain."
As they reported in the Proceedings of the National Academy of Sciences on Monday, the researchers analyzed haplotype profiles for 5,550 UK Biobank participants of European ancestry originating in 47 countries or regions, delving into shared segments of identity-by-descent (IBD) to look at the range of European ancestries present in the population study, and apparent relationships between those populations.
"Recent haplotype sharing analyses in specific European populations have revealed fine-scale genetic differentiation that echoes history," the authors explained. "An equivalent understanding across the whole European continent would place these insights into a wider context and extend understanding to underdescribed regions."
The team attempted to select UK Biobank participants for as many parts of Europe as possible for the analysis, bringing in phenotypic data to help find individuals from a wide range of populations.
From the available genetic data, the researchers uncovered dozens of genetic clusters, along with broad ancestry groups encompassing populations in Northwestern Europe, Central/Eastern Europe, and Southern Europe. They also took a closer look at the genetic gradients that connected populations within and between these regions, including a north-to-south ancestry continuum.
While individuals from some areas showed pronounced haplotype sharing, the team's analyses highlighted more genetically variable parts of Europe and individuals with ancestry that was not easily explained by birth country alone.
The researchers also got a glimpse at more fine-scale population clusters or genetic patterns that prevailed within certain parts of the continent, including British, Irish, Scandinavian, and other ancestry clusters in Northern Europe; Baltic ancestry clusters; and population clusters found in Central, Eastern, and Southern Europe.
Based on these and other findings, the authors suggested that the UK Biobank dataset appears to harbor "a wealth of ancestries not limited to that ancestral to Britain or Ireland, which may be of interest to researchers interested in communities with non-European ancestry potentially sampled in the UKBB."
"Overall," they wrote, "our work has demonstrated a utility of large cosmopolitan biobank studies in providing an informative continental sample of European genotypes. We have leveraged this to expand the map of the European genetic landscape and show genetic signatures of interest to geneticists."