From Science Daily:
No Such Thing As Ethnic Groups, Genetically Speaking, Researchers Say
New research suggests that ethnicity is a constructed social system maintaining genetic boundaries with other groups, rather than being the outcome of common genetic ancestry.
ScienceDaily (Sep. 1, 2009) — Central Asian ethnic groups are more defined by societal rules than ancestry. Researchers writing in the open access journal BMC Genetics found that overall there are more genetic differences within ethnic groups than between them, indicating that separate 'ethnic groups' exist in the mind more than the blood.
Evelyne Heyer, from the Musée de l'Homme in Paris, France, led an international team of researchers who studied mitochondrial DNA and Y chromosome data from several populations of two major language ethnic groups of Central Asia, the Turkic and Indo-Iranian groups.
She said: "Our results indicate that, for at least two of the Turkic groups in Central Asia, ethnicity is a constructed social system maintaining genetic boundaries with other groups, rather than being the outcome of common genetic ancestry."
The boundaries used by individuals to distinguish themselves from members of other ethnic groups are generally cultural, linguistic, economic, religious and political. Heyer and her colleagues confirm the absence of common ancestry in a specific ethnic group; there were on average more differences between members of the same ethnic group than there were between groups.
Speaking about these findings, Heyer said: "Analysis of genetic data, such as in this study, is an important tool for investigating ethnological issues."