Molecular Genetic Analysis Of Ancient Populations In South-middle Inner Mongolia

Anthropologists and archaeologists had long used physical characters and burialcustoms to study social structure, marriage patterns and relationships including raceand culture between populations from different space-time in prehistory and history.However, the application of the techniques of ancient DNA (aDNA) allows us toexplore the past directly and meticulously by the molecular tool. DNA data obtainedfrom ancient human remains can be used to test hypotheses about human origins,evolution, migrations and admixture, and reconstruct ancestor-descendantrelationships between populations. In addition, social organization structure andmarriage patterns in history and prehistory can be elucidated based on aDNA data atlarge. The south-middle Inner Mongolia is located in the east of the Eurasian steppes,where human has grown and propagated from of old. According to the historicrecords, many ethnic populations lived in Mongolian steppes. Some of thepopulations such as Hungs (3rdBC-1rdAD), Turki and Huihu (6rd-9rdAD) andMongols et al. had different effects on the populations from the Eurasian steppes andpopulations from Central Plain. At the same time, the south-middle of InnerMongolia is an area with farming and nomadic cultures interacting upon each otherand belongs to the Great Wall belt in northern China in the cultural history.Therefore, research on the populations from the different space-time in the belt isimportant and far-reaching for the probing into population migrations and gene flowas well as communications and replace of culture between populations.In this article, we systemically analyzed mtDNA from the ancient human remainsexcavated in Xindianzi cemetery from Helinger during Dongzhou periods,Wanggutribe remains of Chengbozi site, and another two ancient populations from Yikeshuand Zhenzishan cemeteries in the Upper Capital site of the Yuan Dynasty, the resultsare as follows:Firstly, we successfully gained the mtDNA HVSI fragments with a 360bp lengthcorresponding to nucleotide positions 16035-16398 of Cambridge reference sequence(CRS) and carried out RFLP analysis. The results showed that the haplogroups of theancient individuals are specific in Asia. we selected 14 populations including Asian,Siberian, Central Asian and European groups as compared populations inphylogenetic analysis, multidimensional scaling analysis and AMOVA analysis, theresults indicate that the ancient population from Xindianzi cemetery in Dongzhouperiod is closer to the extant Siberian populations in matrilineal lineage. Combiningwith the results of molecular biology and physical anthropology and archaeology, wecan conclude that the ancient population is probably herdsmen who migrated fromMongolia altiplano and area of out Baikal, and they can play an important role on theforming process of nomadic culture belt of the Great Wall belt in north China. Inaddition, we find that sampe2 (16223-16298-16327) shares with some individualsboth in East Asia and Siberia as well as a 3600-year-old individual in Sakha Republicin north Siberia. This, on the one hand, probably reflects the gene continuity betweensome ancients from Siberian and some ancients and morderns live in Inner Mongolia;on the other hand, maybe reflect that the ancestors of partial Siberian and East Asiangroups are homologous.Secondly, we performed mtDNA HVSI polymorphisms and RFLP analysis of 12ancient individuals of Wanggu tribe. The haplogroups of five individuals are includedin macrohaplogroup M that is specific in Asia, the haplogroups of another sevenindividuals are included in the macrohaplogroup N that distributes in east Eurasia andwest Eurasia with equal frequency. One of sequences of the ancient individualssharing with CRS belongs to hapolgroup H which accounts for 40%-50% of themtDNA pool in European. Most sequences of Wanggu tribe are shared by Asianincluding East Asian, Siberian and Central Asian, minority of sequences share withEuropean. Phylogenetic analysis and multidimensional scaling analysis show theaffinity of Wanggu tribe and some populations in Central Asia. Moreover, Wanggutribe is the most closely related to the Uzbeks and Uighurs in terms of geneticdistance. At the same time, according to the historic documents, both Uzbeks andUighurs are descendants of Turki. The present study shows that the genetic structureof Wanggu tribe is quite complex in matriline and it is likely from the admixturebetween European and Asian including East Asian and Siberian. The Asian lineageprobably contributes more to the ancient population. Wanggu tribe has a recentcommon origin with Turkic-speaking language Uzbeks and Uighurs, which supportsthe Turkic origin of Wanggu tribe.Thirdly, we analyzed the control region sequence and coding region of mtDNA ofthe ancient individuals from Yikeshu cemetery in the Upper Capital site of the YuanDynasty. Five individuals of Yikeshu site were assigned to hapologroup D, G, Z, andB, the haplogroups are prevalent in some ethnic populations such Daurs and InnerMongols from northern China and some populations in Siberia. The ancientpopulation is closer to Duars and Inner Mongols in genetic distance than othercompared populations.combining with the research of historian on the relationshipbetween Daur and Mongols. We can conclude that Yikeshu ancient population isMongols. At the same time, we also find that the populations who speak the samelanguage from the steppe, to some content, are closer to each other in maternallineage.Finally, we performed mtDNA HVSI polymorphism and RFLP analyses of 21ancient individuals in Zhenzishan cemetery of Upper Capital site of the YuanDynasty. Most of the 21 individuals can be defined by six different haplogroupsincluding A, B, C, D, N9a, Z, and the rest are classified into the macrohaplogroup M.All the haplogroups can be included in mtDNA database of East Asia. Phylogeneticanalysis and principal component analysis were carried out based on DNA data fromextant East Asian, Siberian and Central Asian population. Our research results showthat the ancient populations from Zhenzishan cemetery belong to Han Chinese, andthey can be from the northern Han. Although samples 5, 10, and 17 present certainmorphological character of the component of Caucasoid, the mtDNA haplogroups ofthem is still Asia-specific. Combination with mtDNA variation model of them andthe special historic position of the Upper Capital of the Yuan Dynasty as well asrelative historic records, we conclude that the three individuals are probably thedescendants of men migrated from West Region and Europe and women of the Hannationality migrated from Central Plains.In summary, on the basis of mtDNA data from different space-time popuations inthe Middle-south of Inner Mongolia, our research reveals that the genetic structureand ethnologic origin of the ancient populations as well as the relationships and genecontinuity between the ancient populations and extant populations. At the same time,this article provides molecular evidences for the forming process of nomadic culturebelt of the Great Wall belt in north China and the complicated social structure andpopulation migration model of the Yuan Dynasty.