Vietnam features extensive ethnolinguistic diversity and occupies a key position in Mainland Southeast Asia (MSEA). Yet, the genetic diversity of the country remains relatively unexplored, especially with genome-wide data, because previous studies have focused mainly on the majority Kinh group. In new research, an international team of researchers has analyzed genome-wide SNP (single nucleotide polymorphism) data for the Kinh and other ethnic groups in Vietnam, encompassing all five major language families in MSEA.
Liu et al highlight the importance of genome-wide data from dense sampling of ethnolinguistic groups in providing new insights into the genetic diversity and history of an ethnolinguistically-diverse region, such as Vietnam. Image credit: Quang Nguyen.
The early settlement of anatomically modern humans in MSEA dates back to at least 65,000 years ago and is associated with the formation of a hunter-gatherer tradition called Hoabinhian.
Since the Neolithic period, which dates to about 4,000-5,000 years ago, cultural transitions and diversification have happened multiple times eventually leading to the extraordinary cultural diversity in present day MSEA.
Vietnam has a population size of more than 96 million people comprising 54 official ethnic groups; 110 languages are spoken in the country.
To date, there are hundreds of ethnolinguistic groups in MSEA, speaking languages belonging to five major language families: Austro-Asiatic (AA), Austronesian (AN), Hmong-Mien (HM), Tai-Kadai (TK), and Sino-Tibetan (ST).
In the new study, researchers from the Max Planck Institute for Evolutionary Anthropology, Vientnam’s Institute of Genome Research, the Université de Lyon and CNRS analyzed genome-wide SNP data for the Kinh and 21 additional ethnic groups in Vietnam along with previously-published data from nearby populations and ancient samples.
“We find that the Vietnamese ethnolinguistic groups harbor multiple sources of genetic diversity that are associated with heterogeneous ancestry sharing profiles in each language family,” said corresponding co-author Dr. Nong Van Hai, a scientist in the Institute of Genome Research at the Vietnam Academy of Science and Technology.
“However, the linguistic diversity does not completely match genetic diversity; there have been extensive interactions between the Hmong-Mien and Tai-Kadai groups, and a likely case of cultural diffusion in which some Austro-Asiatic groups shifted to speaking Austronesian languages,” said first author Dr. Dang Liu, a researcher in the Department of Evolutionary Genetics at the Max Planck Institute for Evolutionary Anthropology.
On a global scale, the strongest signal separates most Indian groups from the East Asian groups.
They also found evidence that the majority group Kinh, which have been the focus of previous studies, may not reflect the total Vietnamese diversity.
Within modern Vietnamese groups, individuals from the same language family are mostly placed together.
Within these language families, the ST, HM, and TK groups are mostly separated from AA and AN groups.
Vietnam ethnolinguistic groups overall tend to show the closest relationships with Taiwanese and southern Chinese groups.
“Overall, our results highlight the importance of genome-wide data from dense sampling of ethnolinguistic groups in providing new insights into the genetic diversity and history of an ethnolinguistically-diverse region, such as Vietnam,” said corresponding co-author Dr. Mark Stoneking, also from the Department of Evolutionary Genetics at the Max Planck Institute for Evolutionary Anthropology.
“In contrast to previous studies suggesting a largely indigenous origin of the Vietnamese, we find evidence for extensive contact, over different time periods, between Vietnamese and other groups.”
The research is described in a paper published in the journal Molecular Biology and Evolution.
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Dang Liu et al. Extensive ethnolinguistic diversity in Vietnam reflects multiple sources of genetic diversity. Molecular Biology and Evolution, published online April 28, 2020; doi: 10.1093/molbev/msaa099
