Race, ethnicity, and genomics: social classifications as proxies of biological heterogeneity.

Over the past century, genetics has experienced a tension between the view that racial and ethnic categories are biologically meaningful and the view that these social classifications have little or no biological significance. That tension continues to inform genomics and is evident in the assembly of biological collections and sequence databases that seek to approximate the genetic variation found in human populations. Although social identities can be useful and convenient proxies of some biological features, for example, in ensuring that genomic resources capture a range of genetic variants found in most human populations, the ways in which geneticists conceptualize the relationship between racial and ethnic identities and genetic variation can be problematic. Inclusion of racial and ethnic identifiers in genomic resources can create risks for all members of those identified populations and influence lay perceptions of the nature of racial and ethnic groups. Thus, the burden of showing the scientific utility of racial and ethic identities in the construction and analysis of genomic resources falls on researchers. This requires that genetic researchers pay as much attention to the social constitution of human populations as presently is paid to their genetic composition.