Population structure and history of EBV. (A) Distribution of EBV strains across the world. The inset plot displays the sample-size distribution across time and geography. Sequences with unknown geographic origin were omitted from the plot. (B) Population structure analysis of all the type 1 strains (n = 1205) with varying number of population groupings (K = 2,4, or 7). Strains were labeled with their geographic origin. AF: Africa, EU: Europe, NA: North America, SA: South America, OC: Oceania, AS: Asia, UKN: Unknown geography, NEA: North East Asia, SEA: South East Asia. (C) Principal component analysis (PCA) of the type 1 EBV strains. The first two components explaining 3.30% and 2.29% of the total variance, respectively. Strains were labeled according to their geographic origin. (D) Principal component analysis (PCA) of the type 1 strains from East Asia. Strains from northern and southern China were labelled in different colors. (E) Maximum likelihood tree of the EBV populations (left) and humans (right) constructed using TreeMix. The two trees had minor differences in topology with a Robinson-Fould distance of 2. Review drawing number: GS 京 (2025) 0056号.