Autosomal STRs Provide Genetic Evidence for the Hypothesis That Tai People Originate from Southern China

Abstract

Tai people are widely distributed in Thailand, Laos and southwestern China and are a large population of Southeast Asia. Although most anthropologists and historians agree that modern Tai people are from southwestern China and northern Thailand, the place from which they historically migrated remains controversial. Three popular hypotheses have been proposed: northern origin hypothesis, southern origin hypothesis or an indigenous origin. We compared the genetic relationships between the Tai in China and their “siblings” to test different hypotheses by analyzing 10 autosomal microsatellites. The genetic data of 916 samples from 19 populations were analyzed in this survey. The autosomal STR data from 15 of the 19 populations came from our previous study (Lin et al., 2010). 194 samples from four additional populations were genotyped in this study: Han (Yunnan), Dai (Dehong), Dai (Yuxi) and Mongolian. The results of genetic distance comparisons, genetic structure analyses and admixture analyses all indicate that populations from northern origin hypothesis have large genetic distances and are clearly differentiated from the Tai. The simulation-based ABC analysis also indicates this. The posterior probability of the northern origin hypothesis is just 0.04 [95%CI: (0.01–0.06)]. Conversely, genetic relationships were very close between the Tai and populations from southern origin or an indigenous origin hypothesis. Simulation-based ABC analyses were also used to distinguish the southern origin hypothesis from the indigenous origin hypothesis. The results indicate that the posterior probability of the southern origin hypothesis [0.640, 95%CI: (0.524–0.757)] is greater than that of the indigenous origin hypothesis [0.324, 95%CI: (0.211–0.438)]. Therefore, we propose that the genetic evidence does not support the hypothesis of northern origin. Our genetic data indicate that the southern origin hypothesis has higher probability than the other two hypotheses statistically, suggesting that the Tai people most likely originated from southern China.

Complete mitochondrial genomes of Thai and Lao populations indicate an ancient origin of Austroasiatic groups and demic diffusion in the spread of Tai–Kadai languages

“…divergence times) was used in the simulation process. As the origin time of prehistorical TK-speaking groups is unknown, we employed the existing time of the Tai in southern China of ~3 kya, similar to a previous study (Sun et al 2013). Then, some prehistorical TK groups started to separate from their common ancestor with the Chinese Dai from their homeland in southern China and spread southward to the area of present-day Thailand in the last 1–2 kya (O’Connor 1995; Penth 2000; Pittayaporn 2014).…”

Contrasting paternal and maternal genetic histories of Thai and Lao populations

“…The TK migration during the Bronze Age could have occurred via either demic diffusion (an expansion of TK people that brought both their genes and their language) or cultural diffusion (a language spread with minor movement of people). A genetic study on the origin of TK people supports a southern Chinese origin (Sun et al 2013), while our previous studies of mtDNA genome sequences supports demic diffusion as the best explanation for the origin of the present-day Thai/Lao TK groups, although there is a strong signal of admixture between TK and AA groups in central Thailand ).…”

Gene frequency and haplotype distribution of hemoglobin E among seven minority groups of Yunnan, China

“…Some of these minority groups have a very close relationship with populations of neighboring countries based on shared ethnolinguistic origins and migration history. For example, the Thai, officially named Dai in China, share the same ethnic origin and language family with some Thai populations of Thailand and the Shan ethnic population of Myanmar (Sun et al, 2013).…”