At the time of this writing, our knowledge of East Asian population history is relatively limited compared to that of West Eurasia because less than 5 percent of published ancient DNA data comes from East Asia. The difference reflects the fact that ancient DNA technology was invented in Europe, and it is nearly impossible for researchers to export samples from China and Japan because of government restrictions or a preference that studies be led by local scientists. This has meant that these regions have missed out on the first few years of the ancient DNA revolution.
