Sample identity assurance. (A) The het/hom ratio vs the aut/X ratio is used to infer the gender of each individual. One sample from a male individual with an abnormally high aut/X ratio was substantially more degraded than all others. (B) A scatterplot of the first two principal components derived from the 1000 Genomes genotypes, with individuals colored by major population, and projected ThromboGenomics individuals shown as black circles if they have fewer than 7 candidate variants and triangles if they have at least 7 candidate variants. For clarity, admixed American HapMap individuals are not shown. There is a lower density of ThromboGenomics individuals with African or East Asian ancestry but they all have at least 7 variants, whereas ∼80% of ThromboGenomics individuals with European ancestry have fewer than 7 variants.