The whole discussion on race and genetics in Africa is well discussed in a variety of books, including "Guns, Germs and Steel", which addresses a pretty wide range of topics related to the success of various civilizations over others.
Anyway, given that this East/West Africa debate comes up often, its interesting to note that there was a period in African history called the Bantu expansion, where Bantu speaking peoples of West Africa initially headed east and then South.
Bottom line is that 3000 years ago there were all sorts of people made of different genetic stuff, whereas today most black Africans and their descendants (Carribeans, African Americans) all share a common Bantu heritage. What has occurred since this migration throughout Africa, is that people living in certain areas have adapted to altitude, heat, and other factors related to their geography.
All that to say that it has less to do with who you are than where you're at (and how long your people have thrived there).
By this same logic, once white people have lived at altitude in Colorado for multiple generations and a couple thousand years, you may have similar adaptive behaviour.
Of course according to this same logic you may find that people are far too mobile and intermarry with people from disimilar geography to allow this to happen effectively.