I can obviously understand the biological differences in people of different races. That's a no-brainer.
What I can't understand is how these DNA companies can use DNA to determine countries-of-origin of ancestors. A Caucasian in the U.S. would have similar DNA markers as those people in England, France, etc. An African-American would have similar DNA markers as those people in Africa, the Caribbean, etc. So how can a DNA company say, "You're 50% English, 20% French, etc"? Race is one thing, but country-of-origin would be something else.