An international team led by investigators at the University of Bristol reports in PLoS Genetics this week on its effort to "efficiently capture information on population structure provided by patterns of haplotype similarity." The researchers' approach is based on a coancestry matrix that can be summarized as "chromosome painting," as they call it, in which "each individual in a sample is considered in turn as a recipient, whose chromosomes are reconstructed using chunks of DNA donated by the other individuals." Analyzing Human Genome Diversity Panel data for 938 people and 641,0