An editorial in the NY Times is supposedly meant to show how genetic testing "disproves" the concept of race. A professor gave admixture tests to his students, and some of them were surprised to find out that they had admixture other than what they thought, e.g., blacks with 50% European admixture or a white with 14% African admixture.
Of course, these results actually prove the existence of race. It would be interesting to see how many of the students had anything other than the majority of their ancestry from their self-identified racial group; my guess, based on many autosomal studies to date, is that this percentage would be minimal.
It is of course expected that individuals will have variable proportions of admixture. After all, races are not species, and people from different races have interbed in the past and are continuing to interbreed in the present.
Genetic testing has in fact vindicated the findings of traditional physical anthropology. Physical anthropologists have long believed in continental races, although they may have differed as to the number of these races. Whenever individuals from around the world are clustered based on a large number of loci, invariably the major races emerge as clusters of genetic similarity. Whenever the self-reported race of individuals is compared with their "genotypic" cluster, invariably the two agree.
In regions of the world such as Central Asia, East Africa, or Latin America where traditional physical anthropology has believed that intermixture of races has created mixed-race populations, genetics has invariably shown the hybridity of these populations. Groups such as African Americans who were known to have acquired a large degree of Caucasoid admixture due to the social definition of a "black" in the United States, have been shown to be a group with around 20-25% European admixture.
So, the concept of 'race' has not been debunked by modern genetics. Rather, it has been victoriously confirmed.
John Hawks has much to say about this "debunking" of race, also addressing some problems of the DNA Print test.