Fig. 5: Principal coordinates analysis of populations based on hg R1a1 sub-haplogroup frequencies.
From: Subdividing Y-chromosome haplogroup R1a1 reveals Norse Viking dispersal lineages in Britain

The minimum population size is 10, and pooling was necessary to achieve this in some cases, as follows: IoM+ = Isle of Man, Scotland and Ireland; Germany+ = Germany and Bavaria; Iceland+ = Iceland and Inuit; SW Europe = France, Spain, Portugal and Italy; SE Europe = Bulgaria, Greece, Turkey, Romania and Serbia; NW Europe = Frisia, Netherlands and Denmark. The two ‘GB’ populations omit the Scottish samples. For some populations, sample size was too small for inclusion and reasonable pooling was not possible.