Maternal Genetic Composition of a Medieval Population from a Hungarian-Slavic Contact Zone in Central Europe

Phylogenetic insights into the genetic legacies of Hungarian-speaking communities in the Carpathian Basin

This study focuses on exploring the uniparental genetic lineages of Hungarian-speaking minorities residing in rural villages of Baranja (Croatia) and the Zobor region (Slovakia). We aimed to identify ancestral lineages by examining genetic markers distributed across the entire mitogenome and on the Y-chromosome. This allowed us to discern disparities in regional genetic structures within these communities. By integrating our newly acquired genetic data from a total of 168 participants with pre-existing Eurasian and ancient DNA datasets, our goal was to enrich the understanding of the genetic history trajectories of Carpathian Basin populations. Our findings suggest that while population-based analyses may not be sufficiently robust to detect fine-scale uniparental genetic patterns with the sample sizes at hand, phylogenetic analysis of well-characterized Y-chromosomal Short Tandem Repeat (STR) data and entire mitogenome sequences did uncover multiple lineage ties to far-flung regions and eras. While the predominant portions of both paternal and maternal DNA align with the East-Central European spectrum, rarer subhaplogroups and lineages have unveiled ancient ties to both prehistoric and historic populations spanning Europe and Eastern Eurasia. This research augments the expansive field of phylogenetics, offering critical perspectives on the genetic constitution and heritage of the communities in East-Central Europe.

Genetic history of East-Central Europe in the first millennium CE

BACKGROUND

The appearance of Slavs in East-Central Europe has been the subject of an over 200-year debate driven by two conflicting hypotheses. The first assumes that Slavs came to the territory of contemporary Poland no earlier than the sixth century CE; the second postulates that they already inhabited this region in the Iron Age (IA). Testing either hypothesis is not trivial given that cremation of the dead was the prevailing custom in Central Europe from the late Bronze Age until the Middle Ages (MA).

RESULTS

To address this problem, we determined the genetic makeup of representatives of the IA Wielbark- and MA Slav-associated cultures from the territory of present-day Poland. The study involved 474 individuals buried in 27 cemeteries. For 197 of them, genome-wide data were obtained. We found close genetic affinities between the IA Wielbark culture-associated individuals and contemporary to them and older northern European populations. Further, we observed that the IA individuals had genetic components which were indispensable to model the MA population.

CONCLUSIONS

The collected data suggest that the Wielbark culture-associated IA population was formed by immigrants from the north who entered the region of contemporary Poland most likely at the beginning of the first millennium CE and mixed with autochthons. The presented results are in line with the hypothesis that assumes the genetic continuation between IA and MA periods in East-Central Europe.

Vitamin D Receptor Gene Polymorphisms Affect Osteoporosis-Related Traits and Response to Antiresorptive Therapy

The present study analyzed the effect of vitamin D receptor (VDR) gene polymorphisms (ApaI, TaqI, BsmI, FokI, and Cdx2) on bone mineral density (BMD), biochemical parameters and bone turnover markers, fracture prevalence, and response to three types of antiresorptive therapy (estrogen-progesterone, raloxifene, and ibandronate) in 356 postmenopausal women from Slovakia. Association analysis revealed a significant effect of BsmI polymorphism on lumbar spine BMD, serum osteocalcin (OC), and β-CrossLaps levels. While ApaI and Cdx2 polymorphisms were associated with OC and alkaline phosphatase, TaqI polymorphism affected all turnover markers. ApaI, TaqI, and BsmI genotypes increased the risk of spinal, radial, or total fractures with odds ratios ranging from 2.03 to 3.17. Each of therapy types evaluated had a beneficial effect on all osteoporosis-related traits; however, the VDR gene affected only ibandronate and raloxifene treatment. ApaI/aa, TaqI/TT, and BsmI/bb genotypes showed a weaker or no response to ibandronate therapy in femoral and spinal BMD. The impact of aforementioned polymorphisms on turnover markers was also genotype dependent. On the contrary, only TaqI and BsmI polymorphisms influenced raloxifene therapy, even only in lumbar spine BMD. These results point to the potential of using the VDR gene in personalized pharmacotherapy of osteoporosis.

Mitochondrial DNA Profiles of Individuals from a 12th Century Necropolis in Feldioara (Transylvania)

The genetic signature of modern Europeans is the cumulated result of millennia of discrete small-scale exchanges between multiple distinct population groups that performed a repeated cycle of movement, settlement, and interactions with each other. In this study we aimed to highlight one such minute genetic cycle in a sea of genetic interactions by reconstructing part of the genetic story of the migration, settlement, interaction, and legacy of what is today the Transylvanian Saxon. The analysis of the mitochondrial DNA control region of 13 medieval individuals from Feldioara necropolis (Transylvania region, Romania) reveals a genetically heterogeneous group where all identified haplotypes are different. Most of the perceived maternal lineages are of Western Eurasian origin, except for the Central Asiatic haplogroup C seen in only one sample. Comparisons with historical and modern populations describe the contribution of the investigated Saxon settlers to the genetic history of this part of Europe.

Impact of DNA degradation on massively parallel sequencing-based autosomal STR, iiSNP, and mitochondrial DNA typing systems

Biological samples, including skeletal remains exposed to environmental insults for extended periods of time, exhibit increasing levels of DNA damage and fragmentation. Human forensic identification methods typically use a combination of mitochondrial (mt) DNA sequencing and short tandem repeat (STR) analysis, which target segments of DNA ranging from 80 to 500 base pairs (bps). Larger templates are often unavailable as skeletal samples age and the associated DNA degrades. Single-nucleotide polymorphism (SNP) loci target shorter templates and may serve as a solution to the problem. Recently developed assays for STR and SNP analysis using a massively parallel sequencing approach, such as the ForenSeq kit (Verogen, San Diego, CA), offer a means for generating results from degraded samples as they target templates down to 60 to 170 bps. We performed a modeling study that demonstrates that SNPs can increase the significance of an identification when analyzing DNA down to an average size of 100 bps for input amounts between 0.375 and 1 ng of nuclear DNA. Observations from this study were then compared with human skeletal material results (n = 14, ninth to eighteenth centuries), which further demonstrated the utility of the ForenSeq kit for degraded samples. The robustness of the Promega PowerSeq™ Mito System was also tested with human skeletal remains (n = 70, ninth to eighteenth centuries), resulting in successful coverage of 99.29% of the mtDNA control region at 50× coverage or more. This was accompanied by modifications to a mainstream DNA extraction technique for skeletal remains that improved recovery of shorter templates.

Goth migration induced changes in the matrilineal genetic structure of the central-east European population

For years, the issues related to the origin of the Goths and their early migrations in the Iron Age have been a matter of hot debate among archaeologists. Unfortunately, the lack of new independent data has precluded the evaluation of the existing hypothesis. To overcome this problem, we initiated systematic studies of the populations inhabiting the contemporary territory of Poland during the Iron Age. Here, we present an analysis of mitochondrial DNA isolated from 27 individuals (collectively called the Mas-VBIA group) excavated from an Iron Age cemetery (dated to the 2^nd-4^th century A.D.) attributed to Goths and located near Masłomęcz, eastern Poland. We found that Mas-VBIA has similar genetic diversity to present-day Asian populations and higher diversity than that of contemporary Europeans. Our studies revealed close genetic links between the Mas-VBIA and two other Iron Age populations from the Jutland peninsula and from Kowalewko, located in western Poland. We disclosed the genetic connection between the Mas-VBIA and ancient Pontic-Caspian steppe groups. Similar connections were absent in the chronologically earlier Kowalewko and Jutland peninsula populations. The collected results seem to be consistent with the historical narrative that assumed that the Goths originated in southern Scandinavia; then, at least part of the Goth population moved south through the territory of contemporary Poland towards the Black Sea region, where they mixed with local populations and formed the Chernyakhov culture. Finally, a fraction of the Chernyakhov population returned to the southeast region of present-day Poland and established the archaeological formation called the “Masłomęcz group”.

A genetic perspective on Longobard-Era migrations

From the first century AD, Europe has been interested by population movements, commonly known as Barbarian migrations. Among these processes, the one involving the Longobard culture interested a vast region, but its dynamics and demographic impact remains largely unknown. Here we report 87 new complete mitochondrial sequences coming from nine early-medieval cemeteries located along the area interested by the Longobard migration (Czech Republic, Hungary and Italy). From the same areas, we sampled necropoleis characterized by cultural markers associated with the Longobard culture (LC) and coeval burials where no such markers were found, or with a chronology slightly preceding the presumed arrival of the Longobards in that region (NLC). Population genetics analysis and demographic modeling highlighted a similarity between LC individuals, as reflected by the sharing of quite rare haplogroups and by the degree of genetic resemblance between Hungarian and Italian LC necropoleis estimated via a Bayesian approach, ABC. The demographic model receiving the strongest statistical support also postulates a contact between LC and NLC communities, thus indicating a complex dynamics of admixture in medieval Europe.

The estrogen receptor 1 gene affects bone mineral density and osteoporosis treatment efficiency in Slovak postmenopausal women

BACKGROUND

The study investigated the associations of rs9340799:A > G (XbaI) and rs2234693:T > C (PvuII) polymorphisms in the estrogen receptor 1 gene (ESR1) with femoral neck (BMD-FN) and lumbar spine bone mineral density (BMD-LS), biochemical markers of bone turnover, calcium and phosphate levels, fracture prevalence, and a response to two types of anti-osteoporotic therapy in postmenopausal women from southern Slovakia.

METHODS

We analysed 343 postmenopausal Slovak women (62.40 ± 0.46 years). The influence of rs9340799 (AA vs. AG + GG) and rs2234693 (TT vs. TC + CC) genotypes on BMD and biochemical markers was evaluated by covariance analysis adjusted for age and BMI. Binary logistic regression was used to evaluate the genotype effect on fracture prevalence. Pharmacogenetic part of the study included women who received a regular therapy of HT (17ß estradiol with progesterone; 1 mg/day for both; N = 76) or SERMs/raloxifene (60 mg/day; N = 64) during 48 months. The genotype-based BMD change was assessed by variance analysis for repeated measurements.

RESULTS

Women with AA genotype of rs9340799 had higher BMD-FN (+ 0.12 ± 0.57 of T-score) and BMD-LS (+ 0.17 ± 0.08 of T-score) in comparison with AG + GG. The rs2234693 polymorphism did not affect any of the monitored parameters. No effect of any ESR1 polymorphisms was found on fracture prevalence. Both types of anti-osteoporotic therapy had a positive effect on BMD improvement in FN and LS sites. Considering the effect of the ESR1 gene within the HT, the subjects with rs9340799/AA genotype showed worse response than those with GG genotype (- 0.26 ± 0.10 of BMD-FN T-score; - 0.35 ± 0.10 of BMD-LS T-score) and also with AG genotype (- 0.22 ± 0.08 of BMD-LS T-score). The rs2234693/TT genotype responded poorer in BMD-LS in comparison with TC (- 0.22 ± 0.08 of T-score) and CC (- 0.35 ± 0.09 of T-score). The effect of the ESR1 gene on raloxifene therapy was reported only in BMD-LS. Subjects with rs9340799/AA genotype had a - 0.30 ± 0.11 of T-score worse response compared to AG genotype. The rs2234693/TT genotype showed - 0.39 ± 0.11 and - 0.46 ± 0.15 lower T-scores in comparison with TC and CC genotypes, respectively.

CONCLUSIONS

The rs9340799 polymorphism may contribute to decreased BMD in postmenopausal women from southern Slovakia; however, this is not related to higher fracture prevalence. Concurrently, both polymorphisms affected a response to analysed anti-osteoporotic therapies.

Maternal genetic features of the Iron Age Tagar population from Southern Siberia (1st millennium BC)

Early nomads in the Eurasian steppes since the beginning of the 1st millennium BC played a key role in the formation of the cultural and genetic landscape of populations of a significant part of Eurasia, from Eastern Europe to Eastern Central Asia. Numerous archaeological cultures associated with early nomads have been discovered throughout the Eurasian steppe belt. The Tagar archaeological culture existed in the Minusinsk basin (Sayan Mountains, Southern Siberia, Russia) in the northeastern periphery of the Eurasian steppe belt from the 8th to 1st century BC during the pre-Scythian, Scythian, and Early Xiongnu-Sarmatian periods. In this study, we evaluated mtDNA diversity in the Tagar population based on representative series (N = 79) belonging to all chronological stages of the culture. The Tagar population had a mixed mtDNA pool dominated by Western Eurasian haplogroups and subgroups (H, HV6, HV*, I, K, T, U2e, U4, U5a, and U*) and, to a lesser degree, Eastern Eurasian haplogroups (A*, A8, C*, C5, D, G2a, and F1b). The Tagar population showed a similar mtDNA pool structure to those of other Iron Age populations representing the "Scythian World." We observed particularly high similarity between the Tagar and Classic Scythians from the North Pontic region. Our results support the assumption that genetic components introduced by Bronze Age migrants from Western Eurasia contributed to the formation of the genetic composition of Scythian period populations in Southern Siberia. Another important component of the Tagar mtDNA pool was autochthonous East Eurasian lineages, some of which (A8 and C4a2a) are potential markers of the westward genetic influence of the eastern populations of the Scythian period. Our results suggest a genetic continuity (at least partial) between the Early, Middle, and Late Tagar populations.

Whole mitochondrial genome diversity in two Hungarian populations

Complete mitochondrial genomics is an effective tool for studying the demographic history of human populations, but there is still a deficit of mitogenomic data in European populations. In this paper, we present results of study of variability of 80 complete mitochondrial genomes in two Hungarian populations from eastern part of Hungary (Szeged and Debrecen areas). The genetic diversity of Hungarian mitogenomes is remarkably high, reaching 99.9% in a combined sample. According to the analysis of molecular variance (AMOVA), European populations showed a low, but statistically significant level of between-population differentiation (Fst = 0.61%, p = 0), and two Hungarian populations demonstrate lack of between-population differences. Phylogeographic analysis allowed us to identify 71 different mtDNA sub-clades in Hungarians, sixteen of which are novel. Analysis of ancestry-informative mtDNA sub-clades revealed a complex genetic structure associated with the genetic impact of populations from different parts of Eurasia, though the contribution from European populations is the most pronounced. At least 8% of ancestry-informative haplotypes found in Hungarians demonstrate similarity with East and West Slavic populations (sub-clades H1c23a, H2a1c1, J2b1a6, T2b25a1, U4a2e, K1c1j, and I1a1c), while the influence of Siberian populations is not so noticeable (sub-clades A12a, C4a1a, and probably U4b1a4).

Maternal DNA lineages at the gate of Europe in the 10th century AD

Given the paucity of archaeogenetic data available for medieval European populations in comparison to other historical periods, the genetic landscape of this age appears as a puzzle of dispersed, small, known pieces. In particular, Southeastern Europe has been scarcely investigated to date. In this paper, we report the study of mitochondrial DNA in 10^th century AD human samples from Capidava necropolis, located in Dobruja (Southeastern Romania, Southeastern Europe). This geographical region is particularly interesting because of the extensive population flux following diverse migration routes, and the complex interactions between distinct population groups during the medieval period. We successfully amplified and typed the mitochondrial control region of 10 individuals. For five of them, we also reconstructed the complete mitochondrial genomes using hybridization-based DNA capture combined with Next Generation Sequencing. We have portrayed the genetic structure of the Capidava medieval population, represented by 10 individuals displaying 8 haplotypes (U5a1c2a, V1a, R0a2’3, H1, U3a, N9a9, H5e1a1, and H13a1a3). Remarkable for this site is the presence of both Central Asiatic (N9a) and common European mtDNA haplotypes, establishing Capidava as a point of convergence between East and West. The distribution of mtDNA lineages in the necropolis highlighted the existence of two groups of two individuals with close maternal relationships as they share the same haplotypes. We also sketch, using comparative statistical and population genetic analyses, the genetic relationships between the investigated dataset and other medieval and modern Eurasian populations.

A mosaic genetic structure of the human population living in the South Baltic region during the Iron Age

Despite the increase in our knowledge about the factors that shaped the genetic structure of the human population in Europe, the demographic processes that occurred during and after the Early Bronze Age (EBA) in Central-East Europe remain unclear. To fill the gap, we isolated and sequenced DNAs of 60 individuals from Kowalewko, a bi-ritual cemetery of the Iron Age (IA) Wielbark culture, located between the Oder and Vistula rivers (Kow-OVIA population). The collected data revealed high genetic diversity of Kow-OVIA, suggesting that it was not a small isolated population. Analyses of mtDNA haplogroup frequencies and genetic distances performed for Kow-OVIA and other ancient European populations showed that Kow-OVIA was most closely linked to the Jutland Iron Age (JIA) population. However, the relationship of both populations to the preceding Late Neolithic (LN) and EBA populations were different. We found that this phenomenon is most likely the consequence of the distinct genetic history observed for Kow-OVIA women and men. Females were related to the Early-Middle Neolithic farmers, whereas males were related to JIA and LN Bell Beakers. In general, our findings disclose the mechanisms that could underlie the formation of the local genetic substructures in the South Baltic region during the IA.

Detection of mitochondrial haplogroups in a small avar-slavic population from the eigth-ninth century AD

OBJECTIVES

In the sixth century AD, Avars came to Central Europe from middle Eurasian steppes and founded a strong Empire called the Avar Khagante (568-799/803 AD) in the Pannonian basin. During the existence of this empire, they undertook many military and pugnacious campaigns. In the seventh century, they conquered the northern territory inhabited by Slavs, who were further recruited in Avar military and were commissioned with obtaining food supplies. During almost 200 years of Avar domination, a significant influence by the Avar culture (especially on the burial rite) and assimilation with indigenous population (occurrence of "East Asian"cranial features) could be noticed in this mixed area, which is supported by achaeological and anthropologcal research. Therefore we expected higher incidence of east Eurasian haplogroups (introduced by Avars) than the frequencies detected in present-day central European populations.

MATERIALS AND METHODS

Mitochondrial DNA from 62 human skeletal remains excavated from the Avar-Slavic burial site Cífer-Pác (Slovakia) dated to the eighth and ninth century was analyzed by the sequencing of hypervariable region I and selected parts of coding region. Obtained haplotypes were compared with other present-day and historical populations and genetic distances were calculated using standard statistical method.

RESULTS AND DISCUSSION

In total, the detection of mitochondrial haplogroups was possible in 46 individuals. Our results prooved a higher frequency of east Eurasian haplogroups in our analyzed population (6.52%) than in present-day central European populations. However, it is almost three times lower than the frequency of east Eurasian haplogroups detected in other medieval Avar populations. The statistical analysis showed a greater similarity and the lowest genetic distances between the Avar-Slavic burial site Cifer-Pac and medieval European populations than the South Siberian, East and Central Asian populations.

CONCLUSION

Our results indicate that the transfer of Avar genetic variation through their mtDNA was rather weak in the analyzed mixed population.

PCR: Identification of Genetic Polymorphisms

Polymerase chain reaction (PCR) enables the amplification of a specific sequence of deoxyribonucleic acid (DNA) through the process of three main steps: template DNA denaturation, annealing of the primers to complementary sequences, and primer extension to synthesize DNA strands. By using this method, the target sequence will be copied and amplified at an exponential rate. PCR provides a qualitative method for identifying DNA from fresh or dried cells/body fluids, formalin-fixed archival tissue specimens, and ancient specimens.Herein we describe basic information for performing successful PCR experiments using the amplification of a human Alu insertion on the PV92 gene locus on chromosome 16 as an example method.

Maternal Genetic Ancestry and Legacy of 10(th) Century AD Hungarians

The ancient Hungarians originated from the Ural region in today’s central Russia and migrated across the Eastern European steppe, according to historical sources. The Hungarians conquered the Carpathian Basin 895–907 AD, and admixed with the indigenous communities. Here we present mitochondrial DNA results from three datasets: one from the Avar period (7^th–9^th centuries) of the Carpathian Basin (n = 31); one from the Hungarian conquest-period (n = 76); and a completion of the published 10^th–12^th century Hungarian-Slavic contact zone dataset by four samples. We compare these mitochondrial DNA hypervariable segment sequences and haplogroup results with published ancient and modern Eurasian data. Whereas the analyzed Avars represents a certain group of the Avar society that shows East and South European genetic characteristics, the Hungarian conquerors’ maternal gene pool is a mixture of West Eurasian and Central and North Eurasian elements. Comprehensively analyzing the results, both the linguistically recorded Finno-Ugric roots and historically documented Turkic and Central Asian influxes had possible genetic imprints in the conquerors’ genetic composition. Our data allows a complex series of historic and population genetic events before the formation of the medieval population of the Carpathian Basin, and the maternal genetic continuity between 10^th–12^th century and modern Hungarians.