|Tianyuan Cave (source)|
The information is sketchy as of now but the news in the press indicate that an Homo sapiens from Tianyuan Cave, near Beijing, whose fragmented remains were discovered in 2003, was closely related to modern East Asians and Native Americans.
The paper is not yet online but the information released to the media strongly suggests that East Asians were already distinct from other populations some 40,000 years ago. This would seem to be based on the sequencing of the mitochondrial DNA and the explicit mention of Native Americans indicates that the lineage must be A, B, C or D (X, the fifth and less common matrilineage of Native Americans, is not found in East Asians, with some exceptions from Siberia, so we can exclude it safely).
Ancient DNA from cell nuclei and maternally inherited mitochondria indicates that this individual belonged to a population that eventually gave rise to many present-day Asians and Native Americans, says a team led by Qiaomei Fu and Svante Pääbo, evolutionary geneticists at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
This would seem to discard some adventurous hypothesis floating around about tremendous demographic changes in the Paleolithic and afterwards, at least for this region. Probably not even when "mode 4" technology arrived to the region (from Altai) c. 30,000 years ago.
In other words: the seeds of modern populations were already there c. 40,000 years ago in East Asia (and surely also in most other regions) and, even if they may have changed somewhat, they have remained the same at least to some notable degree.
Furthermore, the autosomal DNA also seems to have been sequenced to at least some degree because the researchers state that Denisovan and Neanderthal genetic inputs are at the same levels as modern North Chinese (i.e. some 0% and 2.5% respectively):
The partial skeleton, unearthed in Tianyuan Cave near Beijing in 2003, carries roughly the same small proportions of Neandertal and Denisovan genes as living Asians do (SN: 8/25/12, p. 22), the scientists report online January 21 in the Proceedings of the National Academy of Sciences.
Or in the words of the Max Plank Institute:
The genetic profile reveals that this early modern human was related to the ancestors of many present-day Asians and Native Americans but had already diverged genetically from the ancestors of present-day Europeans. In addition, the Tianyuan individual did not carry a larger proportion of Neanderthal or Denisovan DNA than present-day people in the region.
This also seems to discard models implying Denisovan admixture happening in Siberia or NE Asia and would indirectly support my own hypothesis of admixture with Homo erectus (for which Denisovans, plausibly an Erectus-Neanderthal hybrid, would be just a proxy) in or near Indonesia.