Fig. 1

Proportion of ancestry inference using first and second PCA score. X and Y axis denote the first and second PCA score generated by FastPop. Red, blue, green and black denote Hapmap samples with European, Africana, Asian ancestry and studied samples with unknown ancestry. The centroids of each population were computed for Hapmap samples. Three lines in dark green were drawn connecting the centroids; six extra line perpendicular to triangle sides and across the centroids were drawn in grey. Individuals in area 1–3 are classified as pure European, Afrian and Asian origin; samples in area 4–6 have mixture origin of two adjacent populations; samples in area 7 have mixture origin of European, African and Asian ancestry. h1, h2 and h3 denote the distance between the samples in the triangle to the sides of the triangle; l1-l6 denote the distance between the image of the sample at the triangle sides and the population