I'm not sure that anyone is "pure" human unless there are some isolated ethnic groups somewhere. From what we know the oldest group seems to be aboriginal Australians.
Recent DNA studies show Africans interbred with other hominids like h. habilis and h.erectus. Europeans have neanderthal. Asians and native Americans have denisovan and neanderthal DNA. In the past few years early hominids from around the Mediterranean and Eastern Europe have been discovered that actually undermine the out of Africa theory and seem to push either a different origin or multi-regional origin of man.