It appears that researchers have identified a bunch of genes that seem to help parse the human family tree. One of the first to get a good look is one called EDAR. The distinctive variant seems to have evolved about 35,000 years ago, and is found mainly in East Asian populations and American Indians. The methods used to elucidate it's consequences were high tech - inserting the gene into a mouse genome.
Gaining a deep insight into human evolution, researchers have identified a mutation in a critical human gene as the source of several distinctive traits that make East Asians different from other races.
The traits — thicker hair shafts, more sweat glands, characteristically identified teeth and smaller breasts — are the result of a gene mutation that occurred about 35,000 years ago, the researchers have concluded.
The discovery explains a crucial juncture in the evolution of East Asians. But the method can also be applied to some 400 other sites on the human genome. The DNA changes at these sites, researchers believe, mark the turning points in recent human evolution as the populations on each continent diverged from one another.