Inherited genetic variation plays a critical but largely uncharacterized role in human differentiation. The completion of the International HapMap Project makes it possible to identify loci that may cause human differentiation. We have devised an approach to find such ethnically variant single-nucleotide polymorphisms (ESNPs) from the genotype profile of the populations included in the International HapMap database. We selected ESNPs using the nearest shrunken centroid method (NSCM), and performed multiple tests for genetic heterogeneity and frequency spectrum on genes having ESNPs. The function and disease association of the selected SNPs were also annotated. This resulted in the identification of 100 736 SNPs that appeared uniquely in each ethnic group. Of these SNPs, 1009 were within disease-associated genes, and 85 were predicted as damaging using the Sorting Intolerant From Tolerant system. This study resulted in the creation of the SNP@Ethnos database, which is designed to make this type of detailed genetic variation approach available to a wider range of researchers. SNP@Ethnos is a public database of ESNPs with annotation information that currently contains 100 736 ESNPs from 10 138 genes, and can be accessed at http://variome.net and http://bioportal.net/ or directly at http://bioportal.kobic.re.kr/SNPatETHNIC/.