Archaeological DNA Data from the XII-XIV Centuries from Ancient Klyazma Settlements / Данные археологических ДНК XII-XIV веков с древних клязьминских поселений

INTRODUCTION

PaleoDNA testing is becoming one of the challenging areas of modern biotechnology. Modern technologies make it possible to qualitatively extract DNA and test it with various methods, including the determination of the Y-chromosome haplogroup and mitochondrial DNA. This can provide valuable information for determining the relationship of the ancient population with other ancient and modern populations. This method of applied historical research is being implemented for 20 years but the data on Slavic and other populations of the beginning of the Russian state is still scarce. The overview is given in ^[4-6]. We know the DNA of no more than 20 old Russian settlements so the data is still scarce. Now for our country the stage of initial "data mining" is still continuing and the first generalization can be made after 40-50 settlements done. So, the forming of the data list of the major settlements within Old Rus border is up to date.

The main goal of this study was to test the haplogroup for two medieval burials from the middle reaches of the Klyazma River and look at its possible counterparts in other medieval DNA samples. Two graves, explored in 2016-2017 at the medieval cemetery of the 12th-14th centuries on the territory of the Patriarch's Garden, were chosen as an object. The burial ground and the settlement adjacent to it are located in the southwestern part of the current territory of the city of Vladimir, on the slope of the cape terrace on the left bank of the Klyazma River. The excavations were carried out by employees of the Vladimir Region Center for Archaelogy S.V. Ocheretina and D.A. Kabaev.

In total, about 180 burials were investigated on an area of more than 1000 m². Burials 7 and 26 from excavation 2 were taken for the experiment.

Burials 7 and 26 were located in different parts of the burial ground. Burial 7 was located in the central part of the burial ground. It dates back to the end of the 13th - beginning of the 14th century and, according to the rite, belongs to the type of Christian burial. Burial 26 was located in the eastern part of the burial ground as part of a group of burials, one of which stood out for its unique embroidered headband. Burial 26 was oriented in accordance with the Orthodox tradition with the head to the west. Hands were folded in the abdomen and pelvis. It dates back to the XII-XIII centuries.

The work to determine the Y-haplogroup of the ancient burial was carried out at "DNA-Nasledie" LLC in January-July 2020 under contracts No. DNA-La / 01-20 dated 10.01.2020 and No. DNA-La / 08-20 dated 14.08.2020. Interpretation of the result were made by the authors.

Materials and methods

DNA from the teeth was extracted using the SiO₂ column method. The resulting DNA was analyzed using standard molecular genetic methods, including real-time PCR on AB7500 equipment. The concentration of isolated DNA was measured on a Qubitv2 fluorimeter.

The concentration of the sample taken for Y-DNA analysis from burial 7 was 15 ng/μL from a powder weighing 6 g. For burial 26, it was 6 ng/μL from a powder weighing 2 g. Fragment analysis for Y-DNA was performed on an AB 3500xl analyzer. A commercial Yfiler™ Plus kit (TermoFisher) for 27 STR markers was used.

The concentration contained DNA fragments from 20 to 180 bp in length. During the PCR reaction, STR fragments of the Y-chromosome with a length of 90 to 180 bp were successfully amplified. For sample 26, some long fragments were not defined due to DNA degradation. As a result of electrophoresis of PCR products on the AB3500xl sequencer and analysis of phoreograms, 27 and 18 STR loci of the Y-chromosome were reliably identified with the allele values indicated in Table 1. The further description of methodology is given in ^[1].

Data and interpretations

As a result of the work, the following data were obtained for haplogroups and subclades of the Y chromosome. Y-DNA analysis of a sample from burial 7 showed the Y-DNA haplogroup R1a-M458, typical of Slavic and other Central European groups. The second sample gave the haplogroup I1-Z58, typical for the Center and North of Europe. The result can be grouped with other still scarce medieval Slavic Y-DNA data from Russia and with results from Central Europe.

The determination of the Y-haplogroup according to www.nevgen.org (the predictor database is dated 08/30/2020) gives a very high probability of subclade R1a-M458-L1029 for sample 7 and subclade I1-Z58 for sample 26.

Table 1.

Discussion and analysis

The subclade R1a-M458 is considered to be a branch inherent in the Slavic and Baltic peoples, with a maximum density distributed in Poland, Lithuania, the Czech Republic, Slovakia, Ukraine and North-West Russia ^[3]. Haplogroup R1a-M458 is found mainly in Central and Eastern Europe. The main territory is limited by Poland, the Czech Republic, and Slovakia. In central and southern Poland, the frequency of the haplogroup reaches its maximum about 40%, while in the North, East and Southwest, the range is from 15 to 23%. In the Czech Republic it is 25%, in Slovakia it is 18–25%. Subclade M458 is also present to the East. In the eastern part of Europe, the frequency of R1a-M458 is still high, for example, 7% to 22% in Belarus, eastern Ukraine and western Russia. The maximum frequencies in Russia were recorded in the Orel region (14%), as well as in the Pskov, Belgorod and Kostroma regions (uniformly up to 12%). It is also present in the Balkans: 9% in Croatia, 8% in Bosnia, 5% in Albania, 5% in Romania, 4% in Greece, 4% in Macedonia, 3% in Serbia, and 2% in Slovenia. In Scandinavia, the frequency of the haplogroup is significantly reduced to 2% in Sweden, although in Denmark it is about 4%.

Haplogroup I1 (or in another designation I1-M253) is the most common type of haplogroup I in Northern Europe, found both among the ancient Sami and in all places covered by the migrations of the ancient Germanic tribes. In Scandinavia and Finland, its frequency is usually more than 35% of Y-chromosomes, and it is quite widely represented further southwards. After Scandinavia, the highest frequencies of I1 are found in other Germanic-speaking regions such as Germany, Austria, the Netherlands, England and the Scottish Lowlands, which have 10% to 20%. It also exists in the Slavic regions, especially in the North. Of the Russian regions, it has the highest concentrations in the Vologda and Arkhangelsk regions, in the city of Kostroma, as well as in the Ryazan and Penza regions, where it is over 10%. The I1-M253-Z58 branch of the I1 haplogroup is mainly inherent in continental Europe especially in the southern shore of the Baltic, where it is more common than in Scandinavia, and it enters the lands of the Baltic and Polabian Slavs.

Two medieval R1a-M458 from Usedom (12th-14th centuries, German-Polish border) ^[7] and Krakauer Berg (11th -14th centuries) ^[8] confirm this point of view. One R1a-M458 was found even further westwards - in the Dutch burial Oldenzaal (14th century) ^[9]. The presence of I1-Z58 was also noted in Krakauer Berg ^[8].

As for the process of settlement of the Upper and Middle Klyazma, the determination of the Y-DNA haplogroups R1a-M458 and I1-Z58 in the burials of the 12th - early 14th centuries does not really contradict the assumption that the ancestors of the buried belonged to the Slavic population settled in North-Eastern Russia. At the same time, the direction of movement from the west through Baltic and Novgorod-Pskov-Tver region has support in this data (for example, the process of movement in the XII century is described in ^[4-6]). Subclade R1a-M458 is found in ancient Russian burials of the Izhora plateau, Yaroslavl, Moscow ^{[10; 11; 12; 13]}.

The Krakauer Berg burial data can be used to explain the joint movement of R1a-M458 and I1-Z58 carriers, but it should be kept in mind that these two haplogroups do not occur simultaneously in the studied population group. A confident interpretation of this data will be possible with the accumulation of broader information on medieval Slavic burials

Conclusion

The paper shows the results of the reseach which took place in 2019-2020. The first evidence of the presence of R1a-M458 and I1-Z58 among the Klyazma population of North-Eastern Russia in the XIII-XVI centuries not only supports the view of the presence of the Y-haplogroup R1a-Z283 for all medieval Russian lands (inhabited by the descendants of the Eastern Slavs), but also hints that a certain genetic unity with the western parts of the Slavic range may exist (since the most serious concentrations of R1a-M458 and I1-Z58 are observed in the western part of the Slavic area).

Acknowledgements

The "DNA History of Russia" project thanks V. Savransky, K. Mkhitaryan, V. Krupnov, I. Shalygin, Andr. Semenov, O. Mokrushina, E. Oleinikova, N. Lipatnikova, O. Tinyaev, G. Tsvetkov, K. Smetanin for their assistance in the project financing and S. Pervov and A. Cheryomin for information support.