Fig. 3: Q fractional genetic cluster estimates across the entire UK Biobank dataset (N = 488,377) obtained using Multi-head Neural ADMIXTURE (K = 6 displayed).
Although results are only displayed for K = 6, the multi-head architecture was trained for K = 2 to K = 6 simultaneously in approximately 11 h. In the barplots (used to visualize Q), each vertical bar represents an individual sample and stacked bar color heights represent the proportion of the sample’s ancestry assigned to that colored genetic cluster. Since they result from unsupervised clustering, interpretation of the cluster colors is left open. a, Q estimates of all the samples. Although many samples are clustered together (blue cluster, representing a northern European/British ancestry component), other clusters emerge reflecting the diverse modern populations now living within the United Kingdom. b, Q estimates of individuals born in the British and Irish Isles and territories. Samples from Gibraltar and the Channel Islands are excluded as they contain a very small number of individuals. c, Q estimates for individuals born outside of the British and Irish Isles are labeled by their country or region of birth, showcasing clusters representing Africans, East Asians, South Asians, Northern Europeans, and West Asians (sharing a cluster in part with Southern Europeans). Despite the large ancestry imbalance, Neural ADMIXTURE characterizes the globally diverse genetic variation found in the UK Biobank. Many UK residents born in other countries appear to have northern European (British) ancestry. These likely represent children born abroad to British parents, who later repatriated. We also note a sizeable South-Asian-like genetic ancestry cluster seen in many individuals born in East Africa. This likely stems from the decolonization era exodus out of East Africa of South Asians, who had settled there during the British Empire. The predicted cluster assignments for K = 2 to K = 6 for individuals born outside of the British and Irish Isles can be found in Extended Data Fig. 5.
