Under the name of “Lua”: Revisiting Genetic Heterogeneity and Population Ancestry of Austroasiatic speakers in Northern Thailand Through Genomic Analysis

Abstract

18 Austroasiatic (AA)-speaking populations in northern Thailand are of significant 19 interest due to their status as indigenous descendants and their location at the crossroads of AA 20 prehistoric distribution across Southern China, the Indian Subcontinent, and Mainland 21 Southeast Asia. However, the complexity of ethnic identification can result in inaccuracies 22 regarding the origin and migration history of these populations. To address this, we conducted 23 a genome-wide SNP analysis on 89 individuals from two Lavue- and three Lwa-endonym 24 populations and combined them with previously published data to elucidate the genetic 25 diversity and clustering of AA groups in northern Thailand. Our findings align with linguistic bioRxiv preprint doi: https://doi.org/10.1101/2024.04.16.589696; this version posted April 20, 2024. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY 4.0 International license. 2 26 classifications, revealing distinct genetic structure among the three branches of the Mon-Khmer 27 subfamily within the AA family: Monic, Khmuic, and Palaungic. Although the term “Lua” 28 ethnicity is used confusingly to identify ethnic groups belonging to both Khmuic and Palaungic 29 branches, our genomic data clarifies that the Khmuic-speaking Lua living on the eastern side 30 of the region show genetic differentiation from the Palaungic-speaking Lavue and Lwa 31 populations living on the western side. Within the Palaungic branch, the Dara-ang population 32 stands out as genetically distinct, reflecting remnants of ancient ancestry. The Lavue 33 populations, mainly inhabiting mountainous areas, exhibit a genetic makeup unique to the AA 34 family, with a close genetic relationship to the Karenic subgroup of the ST family. Conversely, 35 the Lwa and Blang populations, residing in lowland river valleys, display genetic signatures 36 resulting from admixture with Tai-Kadai-speaking ethnic groups. 37 38 Author summary 39 In the past, many Austroasiatic speakers in northern Thailand concealed their identity 40 due to perceptions of inferiority compared to the majority Tai-Kadai-speaking group in the 41 region. However, attitudes have shifted in the modern era, with a greater appreciation for ethnic 42 diversity and the unique aspects of different valuable cultures. This scenario provides an 43 opportunity for us to use genetic insights to untangle the complexities of ethnic identification 44 among these indigenous inhabitants of Mainland Southeast Asia. 45 Through our genetic analysis, we aimed to shed light on the ancestry and diversity of 46 the Austroasiatic people in northern Thailand, often collectively referred to as “Lua” or 47 “Lawa”, which is an exonym (a name of the ethnic group created by another group of people) 48 commonly used in prior scientific reports. Our findings clearly indicate genetic distinctions 49 among the Lua, Lavue, and Lwa ethnic groups. The intricate interplay of genetics, cultural 50 heritage, and historical influences has shaped these ethnic communities. Our study underscores bioRxiv preprint doi: https://doi.org/10.1101/2024.04.16.589696; this version posted April 20, 2024. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY 4.0 International license. 3 51 the importance of accurate ethnic classifications, emphasizing the use of self-identified 52 endonyms, names created and used by the ethnic group themselves. This approach respects the 53 Austroasiatic communities in northern Thailand and acknowledges their significant 54 contributions to advancing our understanding of genetic anthropology. 55 56