Plot of First 4 PCs of NECS Colored by Cluster Allocation. PC1 and PC2 clearly separate the subjects of Jewish descent, shown in purple, from the rest of the subjects and create a northwestern to southeastern European cline. PC3 and PC4 capture further variability within European ethnic groups. The cluster assignments found by the algorithm closely correspond to established ethnic groups across Europe. Based on partial information (birth places and native language of grandparents) of the subjects' ancestry, the clusters were labeled according to the most common ethnic group in the region .
Solovieff et al. BMC Genetics 2010 11:108 doi:10.1186/1471-2156-11-108