Ahh, now we're getting somewhere, there
are genetic
groups of people, but to call them races is, I believe, misleading and incorrect. You didn't address the problem of how to determine the depth to which you must track to disover the magical 'this is a race, but one more or less is not,' point. Sickle cell research actually supports my point, because it is
not present in any one race.
That's right, what you may have commonly read about sickle cell is wildly inaccurate. The rate of occurence for the sickle cell gene is equally present in large populations in Greece, Arabia, Africa, and India in people of extremely different phenotypes, while in southern Africa the people living there, who are by every visible standard almost identical to those of central Africa, do not carry the sickle cell gene (Because they had minimal malaria exposure through their history). There is no way you could, by skin color, hair color, facial features, or any of the other common 'race' descriptors determine if someone was a sickle cell carrier.
The only way to describe them is as having a common ancestor, in the distant past, who developed a persistent trait. Calling such a group a 'race' would be misleading in the extreme, and wouldn't, IMHO, match any of the common definitions of that word.

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