A hierarchical cluster for the HapMap data with a sample of 200 SNPs. A total of 209 unrelated individuals from four populations are shown: CEU (60), YRI (60) and CHB (45) + JPT (44). This figure shows a clustering result using 200 genome-wide random autosomal SNP loci. It is evident that YRI, CEU and CHB+JPT form three distinct clusters. Branch height represents dissimilarity. This figure shows the partial cluster, for the full image please see additional file 1.