Farhan Ali, Guest Writers, Main Stories - Tuesday, December 15, 2009 23:15 - 63 Comments

DNA suggests China Chinese originated from Southeast Asia

Farhan Ali

Recent study shows DNA evidence pointing to an original migration pattern of humans from Southeast Asia to China believed to have happened about 20,000 years ago

Photo courtesy of Salon

The Chinese are the dominant group in Singapore and recently, a senior government politician encouraged Chinese Singaporeans to find out who their ancestors were and where they came from. There is also the current heated debate over the learning of Mandarin by those whose ancestors did not speak Mandarin.

Thus, it is relevant that in a study published just this week in the influential journal Science, the Han Chinese (and other East Asians) have been shown to have originally come from Southeast Asia. Instead of being natives of China, the Han Chinese were in fact immigrants who descended from mainland and island Southeast Asia, the latter historically known as the Malay Archipelago.

This recent study is massive and involved a 40-institution, multi-national (though largely Asian) research team that sampled DNA from over 70 populations throughout Asia. The paper used genetic markers called single-nucleotide polymorphisms (SNPs) which are differences in the chemical ‘lettering’ of DNA, in order to infer patterns of ancestry. And whilst the techniques used were esoteric, this collective pan-Asian effort had an aim close to everyone’s hearts: to recover the lost memory of where we came from.

Southeast Asians Top the Family Tree

Two major findings of this research are worth discussing, the most important being the family tree that was reconstructed by the authors that provides direct evidence that modern Han Chinese came from Southeast Asia. In the tree, all of the Han Chinese populations were descendents of Southeast Asians who formed the top of the tree (analogous to how our great-grandparents would be right at the top in a family tree).

Whilst this has been suggested for almost 10 years, the present study brings the most convincing data and analyses to the table yet. As to when this migration occurred, although the present study did not address this important issue, evidence from other past studies suggests the migration of the Chinese from Southeast Asia probably occurred around 10,000 to 20,000 years ago. The Southeast Asians, in turn, originally came from the southern coasts of Asia which were ultimately populated by humans from East Africa.

The second set of findings pertains to genetic diversity which refers to how similar or different the DNA make-up of individuals in a population are. The genetic diversity is highest in archipelagic Southeast Asia (e.g., Indonesia) with more homogenous (similar) DNA make-up as one goes further North into China.

These findings are important as they provide strong corroboration of the linguistic data from anthropologists and linguists who have discovered an astounding level of linguistic and ethnic diversity in island Southeast Asia, which have hundreds of ethnic groups and languages. The region’s predominant Austronesian language family (which includes Malay) is the world’s most widespread native language family with speakers spanning from Madagascar in Africa to the islands in the Pacific such as Fiji.

(left) The Asian ‘family’ tree with Southeast Asian populations and languages in green, blue and red, and East Asians generally in
purple and yellow. Numbers on branches represent statistical support.

Hard to Accept, But Research is Conclusive

While many Chinese Singaporeans are familiar with the various dialect groups in China, geneticists and linguists know that the diversity of Han Chinese is comparatively low. While some may have elaborate socio-political theories involving the political unity of China, the role of the First Emperor of China and so on, a much simpler and likelier explanation is that diversity, both genetic and cultural, declines as a function of migration. When groups from the ancestral population migrate out into new regions, they bring with them only a very small sample of the original diversity and this is the pattern we find among the Han Chinese. Indeed, even in the modern age, we find this to be true: for example, Asians in America are far less diverse as a group than those in their original homeland.

(left) source: L. Jin et. al. Science

For some, this recovery of the lost memory of the various races in Singapore may be enlightening. For others, it may be as much of a shock as being told one’s father is not his/her real father. But the scientific conclusion is clear, the Chinese in China were immigrants whose ancestors lived in Southeast Asia. The Chinese arrivals in the 19^th and 20^th century in Singapore and Malaysia were actually a return to an ancestral homeland that had been long abandoned, to live with descendents of their ancestors who had long been forgotten, and to relearn a daughter of the ancestral language, Malay – now all but unlearned by the present generation.

The present findings (and others) dispel the notion of any one monolithic “race”. Instead, all of humanity is a cohesive genetic pool with extensive mixing among populations that are changing fluidly. Such mixing among Southeast Asians giving rise to Chinese populations has left indelible marks on our DNA and these marks of our deep shared heritage, remarkably unsullied by divergent recent histories, are a silent but truthful witness against modern self-serving essentialist propaganda proclaiming the contrary.

Reference

Abdulla, M.M. et al. (2009). Mapping human genetic diversity in Asia. Science, 326, 1541-1545. A non-technical summary is also given in the same issue: Normille, D. (2009). SNP Study supports southern migration route to Asia. Science, 326, 1470.