Genomic Insight Into the Population Admixture History of Tungusic-Speaking Manchu People in Northeast China

Population genomics advances in frontier ethnic minorities in China

China, with its large geographic span, possesses rich genetic diversity across vast frontier regions in addition to the Han Chinese majority. Importantly, demographic events and various natural and cultural environments in Chinese frontier regions have shaped the genomic diversity of ethnic minorities via local adaptations. Thus, insights into the genetic diversity and adaptive evolution of these under-represented ethnic groups are crucial for understanding evolutionary scenarios and biomedical implications in East Asian populations. Here, we focus on ethnic minorities in Chinese frontier regions and review research advances regarding genomic diversity, genetic structure, population history, genetic admixture, and local adaptation. We first provide an overview of the extensive genetic diversity across populations in different Chinese frontier regions. Next, we summarize research progress regarding genetic ancestry, demographic history, the adaptive process, and the archaic identification of multiple ethnic minorities in different Chinese frontier regions. Finally, we discuss the gaps and opportunities in genomic studies of Chinese populations and the need for a more comprehensive understanding of genomic diversity and the evolution of populations of East Asian ancestry in the post-genomic era.

AncestryPainter 2.0: Visualizing Ancestry Composition and Admixture History Graph

The earlier version of AncestryPainter is a Perl program that displays the ancestry composition of numerous individuals using a rounded graph. Motivated by the requests of users in practical applications, we updated AncestryPainter to version 2.0 by coding in an R package and improving the layout, providing more options and compatible statistical functions for graphing. Apart from improving visualization functions per se in this update, we added an extra graphing module to visualize genetic distance through radial bars of varying lengths surrounding a core. Notably, AncestryPainter 2.0 allows for multiple pie charts at the center of the graph to display the ancestry composition of more than one target population and implements a method admixture history graph to infer the admixture sequence of multiple ancestry populations. We validated the six admixture history graph metrics using both simulated and real data and implemented a Pearson coefficient-based metric with the best performance in AncestryPainter 2.0. Furthermore, a statistical module was implemented to merge ancestry proportion matrices. AncestryPainter 2.0 is freely available at https://github.com/Shuhua-Group/AncestryPainterV2 and https://pog.fudan.edu.cn/#/Software.

Malaria resistance-related biological adaptation and complex evolutionary footprints inferred from one integrative Tai-Kadai-related genomic resource

Pathogen‒host adaptative interactions and complex population demographical processes, including admixture, drift, and Darwen selection, have considerably shaped the Neolithic-to-Modern Western Eurasian population structure and genetic susceptibility to modern human diseases. However, the genetic footprints of evolutionary events in East Asia remain unknown due to the underrepresentation of genomic diversity and the design of large-scale population studies. We reported one aggregated database of genome-wide SNP variations from 796 Tai-Kadai (TK) genomes, including that of Bouyei first reported here, to explore the genetic history, population structure, and biological adaptative features of TK people from southern China and Southeast Asia. We found geography-related population substructure among TK people using the state-of-the-art population genetic structure reconstruction techniques based on the allele frequency spectrum and haplotype-resolved phased fragments. We found that the northern TK people from Guizhou harbored one TK-dominant ancestry maximized in the Bouyei people, and the southern TK people from Thailand were more influenced by Southeast Asians and indigenous people. We reconstructed fitted admixture models and demographic graphs, which showed that TK people received gene flow from ancient southern rice farmer-related lineages related to the Hmong-Mien and Austroasiatic people and from northern millet farmers associated with the Sino-Tibetan people. Biological adaptation focused on our identified unique TK lineages related to Bouyei, which showed many adaptive signatures conferring Malaria resistance and low-rate lipid metabolism. Further gene enrichment, the allele frequency distribution of derived alleles, and their correlation with the incidence of Malaria further confirmed that CR1 played an essential role in the resistance of Malaria in the ancient "Baiyue" tribes.

Differentiated genomic footprints suggest isolation and long-distance migration of Hmong-Mien populations

BACKGROUND

The underrepresentation of Hmong-Mien (HM) people in Asian genomic studies has hindered our comprehensive understanding of the full landscape of their evolutionary history and complex trait architecture. South China is a multi-ethnic region and indigenously settled by ethnolinguistically diverse HM, Austroasiatic (AA), Tai-Kadai (TK), Austronesian (AN), and Sino-Tibetan (ST) people, which is regarded as East Asia's initial cradle of biodiversity. However, previous fragmented genetic studies have only presented a fraction of the landscape of genetic diversity in this region, especially the lack of haplotype-based genomic resources. The deep characterization of demographic history and natural-selection-relevant genetic architecture of HM people was necessary.

RESULTS

We reported one HM-specific genomic resource and comprehensively explored the fine-scale genetic structure and adaptative features inferred from the genome-wide SNP data of 440 HM individuals from 33 ethnolinguistic populations, including previously unreported She. We identified solid genetic differentiation between HM people and Han Chinese at 7.64‒15.86 years ago (kya) and split events between southern Chinese inland (Miao/Yao) and coastal (She) HM people in the middle Bronze Age period and the latter obtained more gene flow from Ancient Northern East Asians. Multiple admixture models further confirmed that extensive gene flow from surrounding ST, TK, and AN people entangled in forming the gene pool of Chinese coastal HM people. Genetic findings of isolated shared unique ancestral components based on the sharing alleles and haplotypes deconstructed that HM people from the Yungui Plateau carried the breadth of previously unknown genomic diversity. We identified a direct and recent genetic connection between Chinese inland and Southeast Asian HM people as they shared the most extended identity-by-descent fragments, supporting the long-distance migration hypothesis. Uniparental phylogenetic topology and network-based phylogenetic relationship reconstruction found ancient uniparental founding lineages in southwestern HM people. Finally, the population-specific biological adaptation study identified the shared and differentiated natural selection signatures among inland and coastal HM people associated with physical features and immune functions. The allele frequency spectrum of cancer susceptibility alleles and pharmacogenomic genes showed significant differences between HM and northern Chinese people.

CONCLUSIONS

Our extensive genetic evidence combined with the historical documents supported the view that ancient HM people originated from the Yungui regions associated with ancient "Three-Miao tribes" descended from the ancient Daxi-Qujialing-Shijiahe people. Then, some have recently migrated rapidly to Southeast Asia, and some have migrated eastward and mixed respectively with Southeast Asian indigenes, Liangzhu-related coastal ancient populations, and incoming southward ST people. Generally, complex population migration, admixture, and adaptation history contributed to the complicated patterns of population structure of geographically diverse HM people.

Unveiling 2,000 years of differentiation among Tungusic-speaking populations: a revised phylogeny of the paternal founder lineage C2a-M48-SK1061

Previous studies demonstrated Y chromosome haplogroup C2a-M48-SK1061 is the only founding paternal lineage of all Tungusic-speaking populations. To infer the differentiation history of these populations, we studied more sequences and constructed downstream structure of haplogroup C2a-M48-SK1061 with better resolution. In this study, we generated 100 new sequences and co-analyzed 140 sequences of C2a-M48-SK1061 to reconstruct a highly revised phylogenetic tree with age estimates. We also performed the analysis of the geographical distribution and spatial autocorrelation of sub-branches. Dozens of new sub-branches were discovered, many sub-branches were nearly unique for Ewenki, Evens, Oroqen, Xibe, Manchu, Daur, and Mongolian. The topology of these unique sub-branches is the key evidence for understanding the complex evolutionary relationship between different Tungusic-speaking populations. The revised phylogeny provided a clear pattern for the differentiation history of haplogroup C2a-M48-SK1061 in the past 2,000 years. This study showed that the divergence pattern of founder lineage is essential to understanding the differentiation history of populations.

The genetic structure and admixture of Manchus and Koreans in northeast China

BACKGROUND

The fine-scale genetic profiles and population history of Manchus and Koreans remain unclear.

AIM

To infer a fine-scale genetic structure and admixture of Manchu and Korean populations.

SUBJECTS AND METHODS

We collected and genotyped 16 Manchus from Liaoning and 18 Koreans from Jilin province with about 700K genome-wide SNPs. We analysed the data using principal component analysis (PCA), ADMIXTURE, Fst, TreeMix, f-statistics, qpWave, and qpAdm.

RESULTS

Manchus and Koreans showed a genetic affinity with northern East Asians. Chinese Koreans showed a long-term genetic continuity with Bronze Age populations from the West Liao River and had a strong affinity with Koreans in South Korea and Japan. Manchus had a different genetic profile compared with other Tungusic populations since the Manchus received additional genetic influence from the southern Chinese but didn't have West Eurasian-related admixture.

CONCLUSIONS

The genetic formation of Manchus involving southern Chinese was consistent with the extensive interactions between Manchus and populations from central and southern China. The large-scale genetic continuity between ancient West Liao River farmers and Koreans highlighted the role farming expansion played in the peopling of the Korean Peninsula.

Genetic structure and demographic history of Northern Han people in Liaoning Province inferred from genome-wide array data

In this study, we used typical and advanced population genetic analysis methods [principal component analysis (PCA), ADMIXTURE, FST, f3-statistics, f4-statistics, qpAdm/qpWave, qpGraph, ALDER (Admixture-induced Linkage Disequilibrium for Evolutionary Relationships) and TreeMix] to explore the genetic structure of 80 Han individuals from four different cities in Liaoning Province and reconstruct their demographic history based on the newly generated genome-wide data. We found that Liaoning Han people have genetic similarities with other northern Han people (Shandong, Henan, and Shanxi) and Liaoning Manchu people. Millet farmers in the Yellow River Basin (YRB) and the West Liao River Basin (WLRB) (57–98%) and hunter-gatherers in the Mongolian Plateau (MP) and the Amur River Basin (ARB) (40–43%) are the main ancestral sources of the Liaoning Han people. Our study further supports the “northern origin hypothesis”; YRB-related ancestry accounts for 83–98% of the genetic makeup of the Liaoning Han population. There are clear genetic influences of northern East Asian populations in the Liaoning Han people, ancient Northeast Asian-related ancestry is another dominant ancestral component, and large-scale population admixture has happened between Tungusic Manchu people and Han people. There are genetic differences among the Liaoning Han people, and we found that these differences are associated with different migration routes of Hans during the “Chuang Guandong” period in historical records.

Genomic insights into the genetic structure and population history of Mongolians in Liaoning Province

The Mongolian population exceeds six million and is the largest population among the Mongolic speakers in China. However, the genetic structure and admixture history of the Mongolians are still unclear due to the limited number of samples and lower coverage of single-nucleotide polymorphism (SNP). In this study, we genotyped genome-wide data of over 700,000 SNPs in 38 Mongolian individuals from Fuxin in Liaoning Province to explore the genetic structure and population history based on typical and advanced population genetic analysis methods [principal component analysis (PCA), admixture, F_ST, f₃-statistics, f₄-statistics, qpAdm/qpWave, qpGraph, ALDER, and TreeMix]. We found that Fuxin Mongolians had a close genetic relationship with Han people, northern Mongolians, other Mongolic speakers, and Tungusic speakers in East Asia. Also, we found that Neolithic millet farmers in the Yellow River Basin and West Liao River Basin and Neolithic hunter–gatherers in the Mongolian Plateau and Amur River Basin were the dominant ancestral sources, and there were additional gene flows related to Eurasian Steppe pastoralists and Neolithic Iranian farmers in the gene pool of Fuxin Mongolians. These results shed light on dynamic demographic history, complex population admixture, and multiple sources of genetic diversity in Fuxin Mongolians.

Systematic selections and forensic application evaluations of 111 individual identification SNPs in the Chinese Inner Mongolia Manchu group

Single nucleotide polymorphism (SNP) possesses a promising application in forensic individual identification due to its wide distribution in the human genome and the ability to carry out the genotyping of degraded biological samples by designing short amplicons. Some commonly used individual identification SNPs are less polymorphic in East Asian populations. In order to improve the individual identification efficiencies in East Asian populations, SNP genetic markers with relatively higher polymorphisms were selected from the 1,000 Genome Project phase III database in East Asian populations. A total of 111 individual identification SNPs (II-SNPs) with the observed heterozygosity values greater than 0.4 were screened in East Asian populations, and then, the forensic efficiencies of these selected SNPs were also evaluated in Chinese Inner Mongolia Manchu group. The observed heterozygosity and power of discrimination values at 111 II-SNPs in the Inner Mongolia Manchu group ranged from 0.4011 to 0.7005, and 0.5620 to 0.8025, respectively, and the average value of polymorphism information content was greater than 0.3978. The cumulative match probability and combined probability of exclusion values at II-SNPs were 7.447E^-51 and 1-4.17E^-12 in the Inner Mongolia Manchu group, respectively. The accumulative efficiency results indicated that the set of II-SNPs could be used as a potential tool for forensic individual identification and parentage testing in the Manchu group. The sequencing depths ranged from 781× to 12374×. And the mean allele count ratio and noise level were 0.8672 and 0.0041, respectively. The sequencing results indicated that the SNP genetic marker detection based on the massively parallel sequencing technology for SNP genetic markers had high sequencing performance and could meet the sequencing requirements of II-SNPs in the studied group.

Genomic Insights Into the Genetic Structure and Natural Selection of Mongolians

Mongolians dwell at the Eastern Eurasian Steppe, where is the agriculture and pasture interlaced area, practice pastoral subsistence strategies for generations, and have their own complex genetic formation history. There is evidence that the eastward expansion of Western Steppe herders transformed the lifestyle of post-Bronze Age Mongolia Plateau populations and brought gene flow into the gene pool of Eastern Eurasians. Here, we reported genome-wide data for 42 individuals from the Inner Mongolia Autonomous Region of North China. We observed that our studied Mongolians were structured into three distinct genetic clusters possessing different genetic affinity with previous studied Inner Mongolians and Mongols and various Eastern and Western Eurasian ancestries: two subgroups harbored dominant Eastern Eurasian ancestry from Neolithic millet farmers of Yellow River Basin; another subgroup derived Eastern Eurasian ancestry primarily from Neolithic hunter-gatherers of North Asia. Besides, three-way/four-way qpAdm admixture models revealed that both north and southern Western Eurasian ancestry related to the Western Steppe herders and Iranian farmers contributed to the genetic materials into modern Mongolians. ALDER-based admixture coefficient and haplotype-based GLOBETROTTER demonstrated that the former western ancestry detected in modern Mongolian could be recently traced back to a historic period in accordance with the historical record about the westward expansion of the Mongol empire. Furthermore, the natural selection analysis of Mongolians showed that the Major Histocompatibility Complex (MHC) region underwent significantly positive selective sweeps. The functional genes, alcohol dehydrogenase (ADH) and lactase persistence (LCT), were not identified, while the higher/lower frequencies of derived mutations were strongly correlated with the genetic affinity to East Asian/Western Eurasian populations. Our attested complex population movement and admixture in the agriculture and pasture interlaced area played an important role in the formation of modern Mongolians.