gene_tailor's Journal: Genes/race continued

More on the same topic... I thought the controversial Human Diversity Genome project ("an effort by anthropologists, geneticists, doctors, linguists, and other scholars from around the world to document the genetic variation of the human species worldwide") had crashed and burned about 5 years ago, but their website is still around here. Their FAQ contains this quote,

Scientists already know at least one interesting thing about these kinds of genetic variation [referring to "those in portions of the genome that do not code for proteins, those changes in the genes that don't change the resulting proteins, and those that do make some differences in the body's structure or performance"] Although there are genetic differences between groups, the extent of such difference is small compared with the amount of difference found within a group. People within "ethnic groups" are genetically more different from each other than their group is from other groups.

Are ethnic groups genetically definable? As far as scientists know, no particular genes make a person Irish or Chinese or Zulu or Navajo. These are cultural labels, not genetic ones. People in those populations are more likely to have some alleles in common, but no allele will be found in all members of one population and in no members of any other. (There may be rare variations, however, that are found only in some populations.) This cannot be very surprising, in light of the vast extent of intermarriage among human populations, now and throughout history and prehistory. There is no such thing as a genetically "pure" human population.

This is the sort of information I was looking for, but they cite no references and their FAQ is nearly a decade old, which is ancient in scientific terms. I'll keep looking for data on this.