Russian Karelian Research Articles

Eastern Fennoscandian Wolf (<i>Canis lupus</i> L.) under the Heavy Hunting Pressure: mtDNA Analysis as a Tool to Assess Hunting Impact on the Population-Genetic Structure

One of the most ancient aspects of human impact on the wild animals is hunting. The degree of human impact on one of the Eastern Fennoscandian wolf (Canis lupus L.) population based on the analysis of data on the population dynamics of the predator and its preys, “hunting bag” data, changes in the spatial-temporal structure and genetic characteristics, is shown. In the presented work, a genetic analysis of the control region mtDNA of the wolf of the Republic of Karelia (Russia) and the experimental territory (Kondopozhsky district of Karelia) was performed on a time slice of 10 years. The modern mtDNA haplotypic diversity of Russian Karelian and Finnish wolf population, in comparison with the general diversity characteristic for the species, is poor. In total, only two haplotypes common in Eurasia have been identified here, which is obviously explained by the history of the species – the stages of severe population decline.

Highly productive fishing in Lake Onega? New data on the subsistence basis of the Late Stone age populations in Russian Karelia

Recent excavations of the site of Fofanovo XIII (ca. 3500 to 3000 cal BC) on the western shore of Lake Onega, Russian Karelian, yielded evidence of production of Russian Karelian axes and adzes, as well as a rich faunal assemblage. Consisting mainly of unburnt bones, this assemblage represents a rare occurrence in Karelia and the neighboring regions of Russia and Finland, and sheds light on the subsistence of the Late Neolithic / Eneolithic populations of the Lake Onega. Fish bones overwhelmingly dominate, indicating a primary reliance on aquatic food resources, with the most common species being zander (over 80 %) and pike (ca. 9 %). In the specific natural conditions of the Early Subboreal in Lake Onega, zander was the species that could yield the maximal return of the invested effort, and this caused a very narrow specialization of fishing activities. The stable food supply provided by fishing favored tendencies towards complexity, which are evident through studies of the Russian Karelian industry. The analysis of the annual rings of zander vertebrae indicates that the site was in use during the snowless season. The identification of ringed seal, Atlantic sturgeon, and Wels catfish, which are not present in the lake nowadays, are also important results of the analysis.

Made for exchange: the Russian Karelian lithic industry and hunter-fisher-gatherer exchange networks in prehistoric north-eastern Europe

The hunter-fisher-gatherers of fourth- to third-millennium BC north-eastern Europe shared many characteristics traditionally associated with Neolithic and Chalcolithic agricultural societies. Here, the authors examine north-eastern European hunter-fisher-gatherer exchange networks, focusing on the Russian Karelian lithic industry. The geographically limited, large-scale production of Russian Karelian artefacts for export testifies to the specialised production of lithic material culture that was exchanged over 1000km from the production workshops. Functioning both as everyday tools and objects of social and ritual engagement, and perhaps even constituting a means of long-distance communication, the Russian Karelian industry finds parallels with the exchange systems of contemporaneous European agricultural populations.

Whole-genome analyses provide no evidence for dog introgression in Fennoscandian wolf populations.

Hybridization and admixture can threaten the genetic integrity of populations and be of particular concern to endangered species. Hybridization between grey wolves and dogs has been documented in many wolf populations worldwide and is a prominent example of human‐mediated hybridization between a domesticated species and its wild relative. We analysed whole‐genome sequences from >200 wolves and >100 dogs to study admixture in Fennoscandian wolf populations. A principal component analysis of genetic variation and admixture showed that wolves and dogs were well‐separated, without evidence for introgression. Analyses of local ancestry revealed that wolves had <1% mixed ancestry, levels comparable to the degree of mixed ancestry in many dogs, and likely not resulting from recent wolf–dog hybridization. We also show that the founders of the Scandinavian wolf population were genetically inseparable from Finnish and Russian Karelian wolves, pointing at the geographical origin of contemporary Scandinavian wolves. Moreover, we found Scandinavian‐born animals among wolves sampled in Finland, demonstrating bidirectional gene flow between the Scandinavian Peninsula and eastern countries. The low incidence of admixture between wolves and dogs in Fennoscandia may be explained by the fact that feral dogs are rare in this part of Europe and that careful monitoring and management act to remove hybrids before they backcross into wolf populations.

Geochemistry of komatiites and basalts in Archean greenstone belts of Russian Karelia with emphasis on platinum-group elements

Archean komatiites form an important host rock for Ni-Cu sulfide deposits in the world. In this study, we examined Archean komatiites and komatiitic basalts from four areas in the Vedlozero-Segozero greenstone belt and two areas in the Tikshozero greenstone belt, Russian Karelia, to constrain their Ni-Cu sulfide mineralization potential using chalcophile element geochemistry. The platinum-group element (PGE) concentrations in these Munro-type komatiitic rocks are at a level of other similar S-undersaturated komatiites and komatiitic basalts globally, with Pt and Pd concentrations in the range of 5–20 ppb and Pd/Ir varying from < 10 (komatiites) to > 15 (komatiitic basalts and basalts). Generally, the metals of the iridium-group elements (IPGEs; Ir, Ru, Os) show a compatible behavior, decreasing in abundance with decreasing MgO, whereas the metals of the palladium group (PPGEs; Pt, Pd, Rh) exhibit an incompatible behavior. The poor correlation between Ir and MgO suggests that olivine fractional crystallization is not the main control on the behavior of IPGE. In contrast, Ir, Ru, and Os show positive correlations with Cr, which is consistent with the compatible behavior of IPGEs in chromite or during the co-precipitation of chromite and platinum-group minerals (PGMs). Palladium, Cu, and Au have been variably mobile during alteration and metamorphism whereas Pt appears to have been less mobile. Some samples from the Khizovaara area show low (Pt/Ti)N ratios, low Ni, and high La/Sm and La/Nb, suggesting localized sulfide saturation in response to crustal contamination. However, the potential of the Russian Karelian greenstone belts for Ni-Cu sulfide mineralization is considered relatively low because most samples show neither enrichment nor depletion of chalcophile elements, and the paucity of dynamic lava channel environments, as indicated by the scarcity of olivine-rich adcumulates. In addition, there appears to be a lack of exposed sulfidic sedimentary rocks in the region.

No simple answers for the Finnish and Russian Karelia allergy contrast: Methylation of CD14 gene.

Finnish and Russian Karelian children have a highly contrasting occurrence of asthma and allergy. In these two environments, we studied associations between total serum immunoglobulin E (IgE) with methylation levels in cluster of differentiation 14 (CD14). Five hundred Finnish and Russian Karelian children were included in four groups: Finnish children with high IgE (n = 126) and low IgE (n = 124) as well as Russian children with high IgE (n = 125) and low IgE (n = 125). DNA was extracted from whole blood cells and pyrosequenced. Three CpG sites were selected in the promoter region of CD14. Methylation levels in two of the three CpG sites were higher in the Finnish compared to Russian Karelian children. In the promoter area of CD14, the Finnish compared to Russian children with low IgE had a significant (p < 0.0001) increase in methylation levels at the Amp5Site 2. Likewise, the Finnish compared to Russian children with high IgE had a significant (p = 0.003) increase in methylation levels at the Amp5Site 3. In Russian children with low vs. high IgE, there were significant differences in methylation levels, but this was not the case on the Finnish side. In the regression analysis, adding the methylation variation of CD14 to the model did not explain the higher asthma and allergy risk in the Finnish children. The methylation levels in the promoter region of CD14 gene were higher in the Finnish compared to Russian Karelian children. However, the methylation variation of this candidate gene did not explain the asthma and allergy contrast between these two areas.

Evidence of post‐glacial secondary contact and subsequent anthropogenic influence on the genetic composition of Fennoscandian moose (Alces alces)

AbstractAimTo determine whether a contemporary population of the moose (Alces alces), a large northern ungulate, retains genetic signatures of post‐glacial recolonization and/or the effects of anthropogenic factors. We focused on investigating spatial genetic structure and the distribution of genetic diversity of this species to clarify its still obscure history.LocationEastern Fennoscandia, Northern Europe.MethodsIn total, 574 Finnish and Russian Karelian moose were genotyped at 16 microsatellite loci, and the mitochondrial control region was sequenced from 224 individuals. Spatially explicit Bayesian clustering, multivariate and spatial autocorrelation methods were applied alongside traditional F‐statistics to study the effects of landscape on genetic structure. The demographic history of our study populations was explored with coalescent analysis and Bayesian skyline plots.ResultsA major mitochondrial divergence of moose was discovered between northern parts of Finland and the rest of the studied area. Landscape genetic analyses on the microsatellite data identified three genetic clusters connected by clines, with coalescent analysis indicating the division to be of ancient origin. Additionally, recent population bottlenecks were detected using Bayesian skyline plots.Main conclusionsOur results indicate a post‐glacial secondary contact between two distinct moose mitochondrial lineages that diverged during the Pleistocene, whereas admixture of three diverged genetic subpopulations was detected using microsatellites. The emergence of these subpopulations was estimated to have occurred after the post‐glacial recolonization of Fennoscandia. The observed genetic bottlenecks coincide with recorded historical population declines in the 18th century. We conclude that the contemporary genetic composition of the moose population in eastern Fennoscandia has been affected by both ancient and recent factors.

Rattling Sabres and Evil Intruders: The Border, Heroes and Border-crossers in Panfennist and Soviet Socialist Realist Literature

In this article I analyse Russian and Soviet Karelian literary texts written in Finnish at the time and in the style of socialist realism, and Finnish poems, songs and novels of the same era, proposing the idea of a ‘Greater-Finland’. I turned my attention to the question of how the depiction, construction and use of borders is handled in the respective texts, and look to determine whether the opposed ideologies of Soviet Communism and Panfennism led to similar or different artificial results. This analysis proves that the texts of the two ideologies generally draw strict distinctions between the ‘heroes’ of their own side and the bad ‘Others’. Only the heroes of the plot are able to either cross borders or to establish new ones. While in the Soviet texts opponents of Soviet society inside the Soviet Union are depicted as foreign and separated through ideological, symbolic and topographical borders, the Karelians in the Finnish texts are suspected as a hybrid people, spoiled by their contact with the evil Russians.

Non-Russian Language Space and Border in Russian Karelian Literature

This article examines Finnish language literature in Russian Karelia on the Russian–Finnish national borderland from the 1940s until the 1970s. It focuses on the concepts of the non-Russian language space and border that are constructed and studied in the context of three novels: Iira (1947), Tiny White Bird (1961), and We Karelians (1971). The article claims that the non-Russian language space and the national border started to be understood differently from the official degrees dictated by Moscow, as found in literature already from the late 1950s and early 1960s. From the 1950s onwards, the historical, linguistic, and cultural roots across the national border and the Finnish population were allowed to be recognized in literature. Furthermore, this article claims that in the 1970s, literature was able to represent such regional history, and also the closeness and permeability of the national border that influenced the lives of the Soviet Karelian non-Russian speaking population and their identity formation. This led to different ideas of the national border, in which the border and its functions and meanings became gradually more multi-voiced, ambivalent and controversial, in comparison to the conceptualization of the border as presenting a strict, impermeable boundary.

Balancing selection and heterozygote advantage in major histocompatibility complex loci of the bottlenecked Finnish wolf population

Maintaining effective immune response is an essential factor in the survival of small populations. One of the most important immune gene regions is the highly polymorphic major histocompatibility complex (MHC). We investigated how a population bottleneck and recovery have influenced the diversity and selection in three MHC class II loci, DLA-DRB1, DLA-DQA1 and DLA-DQB1, in the Finnish wolf population. We studied the larger Russian Karelian wolf population for comparison and used 17 microsatellite markers as reference loci. The Finnish and Karelian wolf populations did not differ substantially in their MHC diversities (GST″=0.047, P=0.377), but differed in neutral microsatellite diversities (GST″=0.148, P=0.008). MHC allele frequency distributions in the Finnish population were more even than expected under neutrality, implying balancing selection. In addition, an excess of nonsynonymous compared to synonymous polymorphisms indicated historical balancing selection. We also studied association between helminth (Trichinella spp. and Echinococcus canadensis) prevalence and MHC diversity at allele and SNP level. MHC-heterozygous wolves were less often infected by Trichinella spp. and carriers of specific MHC alleles, SNP haplotypes and SNP alleles had less helminth infections. The associated SNP haplotypes and alleles were shared by different MHC alleles, which emphasizes the necessity of single-nucleotide-level association studies also in MHC. Here, we show that strong balancing selection has had similar effect on MHC diversities in the Finnish and Russian Karelian wolf populations despite significant genetic differentiation at neutral markers and small population size in the Finnish population.

Disparity of innate immunity–related gene effects on asthma and allergy on Karelia

We investigated the interactive effects of 11 innate immunity-related genes (IL10, IL12b, IL8, TLR2, TLR4, CD14, IFNGR, CC16, IFNg, CMA1, and TGFB) and four IgE response genes (IL4, IL13, IL4RA, and STAT6) with 'Western' or 'Eastern' environments/lifestyles on asthma and allergy in Karelian children. Karelian children (412 Finnish and 446 Russian) were recruited and assessed for a range of allergic conditions, with 24 single-nucleotide polymorphisms genotyped in 15 genes. The genotype-phenotype relationships differed in Finnish and Russian Karelian children. The interaction between polymorphisms and the variable representing 'Western' and 'Eastern' environments/ lifestyles was significant for IL10-1082 (p = 0.0083) on current rhinitis, IL12b 6408 on current conjunctivitis (p = 0.016) and atopy (p = 0.034), IL8 781 on atopic eczema (p = 0.0096), CD14 -550 on current rhinitis (p = 0.022), IFNgR1 -56 on atopic eczema(p = 0.038), and STAT6 2964 on current itchy rash (p = 0.037) and total serum IgE (p = 0.042). In addition, the G allele of IL13 130 was associated with a lower level of total serum IgE in Finnish (p = 0.003) and Russian (p = 0.01) children and overall (pooling the two populations together, p = 0.00006). After adjusting for multiple tests, the association between IL13 130 and IgE and the interactive effects of IL10-1082 on current rhinitis and IL8 781 on atopic eczema were significant by controlling a false-positive rate of 0.05 and 0.10, respectively. Living in an Eastern vs. Western environment was associated with a different genetic profile associated with asthma and allergy in the Karelian populations.

Co-occurrence of allergic sensitization and type 1 diabetes

Background. The mechanisms leading to abnormal immune regulation in type 1 diabetes and allergic diseases may be partly overlapping. If so, these diseases should co-occur more often than expected. We investigated this phenomenon in two contrasting socio-economic environments, Finland and Russian Karelia.Methods. We screened 413 Finnish children (of whom 147 had type 1 diabetes) and 244 Russian Karelian children (132 had type 1 diabetes) for total immunoglobulin E (IgE) levels and specific IgE against birch, cat, and egg albumen. In addition we analysed diabetes-related human leukocyte antigen (HLA) haplotypes and antibodies against hepatitis A virus (HAV) and recorded allergic diseases by a questionnaire in Russian Karelia.Results. In Russian Karelia 15% of the patients with type 1 diabetes, but only 4% of the control subjects had allergen-specific IgE (P = 0.012). A similar difference was observed in the frequency of allergic symptoms. Co-occurrence of allergic sensitization and type 1 diabetes was associated with lack of HAV antibodies and was not seen in Finland where infections are less frequent than in Karelia.Conclusion. Our findings support the idea of common mechanisms in the pathogenesis of allergic diseases and type 1 diabetes, which may be particularly important in an environment with low penetrance of these diseases.

Opposite gene by environment interactions in Karelia for CD14 and CC16 single nucleotide polymorphisms and allergy

Finnish Karelians have a higher prevalence of allergic disease than Russian Karelians. As both populations are generally from the same ethnic group, the Karelian population offers a unique opportunity to analyse genetic and allergic disease interactions between 'Western' and 'Eastern' environments. We investigated associations between allergic diseases and CD14 and CC16 polymorphisms in Finnish vs Russian Karelian women. Adult female Karelians (330 Finnish and 274 Russian) were recruited, examined for a range of symptoms and conditions including rhinitis, itchy rash, asthma and atopy and genotyped for CD14 C-159T and CC16 A38G. For both CD14 C-159T and CC16 A38G, the risk allele for atopic phenotypes in Finnish Karelia was the protective allele in Russian Karelia. For CD14 C-159T, an interactive effect on ever itchy rash (P(interaction) = 0.004), itchy rash <12 mo (P(interaction) = 0.001) and dry cough at night in the past 12 months (<12 months) (P(interaction) = 0.011) was found; the risk allele was C in Russians and T in Finns. For CC16 A38G, an interaction was significant for ever rhinitis (P(interaction) = 0.006), rhinitis <12 mo (P(interaction) = 0.004), and marginally significant for ever hayfever (P(interaction) = 0.07), allergic eye symptoms <12 mo (P(interaction) = 0.09); their risk allele was G in Russians and A in Finns. An Eastern vs Western environment appears to exert an effect via opposite alleles on risk of allergic diseases in adult women.

Interaction between CD14−159C&gt;T polymorphism and Helicobacter pylori is associated with serum total immunoglobulin E

Total serum IgE is regulated by both environmental and genetic factors. Association and linkage studies have suggested a role of CD14-159C>T polymorphism in the regulation of serum total IgE, but the results have been contradictory. It seems that gene-environment interactions are involved in this regulation. The aim of this study was to examine the possible gene-environment interactions among Toxoplasma gondii, Helicobacter pylori, CD14-159C>T and Toll-like receptor (TLR) 4+896A>G polymorphism on serum total IgE. For this study, we expanded the scope of our earlier comparison of allergic sensitization and microbial load between Finland and Russian Karelia by studying the CD14-159C>T and TLR4+896A>G polymorphism in a cohort of Russian Karelian children. For this study, CD14-159C>T and TLR4+896A>G polymorphisms were analysed in 264 healthy Russian Karelian children. Serum total IgE levels and H. pylori and T. gondii antibodies were also measured. We constructed a multiway anova model to analyse the gene-environment interactions among T. gondii seropositivity, H. pylori seropositivity, CD14-159C>T and TLR4+896A>G polymorphisms on serum total IgE. The model showed that there was an interaction between the CD14-159 allele T carrier status and H. pylori antibodies on serum total IgE (P=0.004). No other interactions were found. Our results further emphasize the role of gene-environment interaction in the regulation of serum total IgE.

Predominance of Gram‐positive bacteria in house dust in the low‐allergy risk Russian Karelia

Simple living conditions and farming environment have been associated with reduced risk for allergic diseases such as atopy and asthma but the factors responsible for this effect remain unresolved. We examined the bacterial composition of house dusts obtained from Finnish and Russian Karelia, two adjacent areas with high and low occurrence of atopic diseases respectively. Two dust mixes, both composed of 10 randomly selected dust samples from 349 Finnish and 417 Russian Karelian households were studied for bacterial biomarkers (DNA, Limulus-active endotoxin, 3-OH fatty acids, muramic acid) and for 16S rRNA gene sequences. Overall, the DNA cloning revealed more taxons (94 different genera) of dustborne bacteria than seen in any previous study on residential environments. Majority (67%) of the bacterial DNA clones in house dust from the low-allergy Russian Kareliarepresented Gram-positive bacteria (Firmicutes and Actinobacteria), predominantly Staphylococcaceae and Corynebacteriaceae. Russian Karelian dust showed up to 20-fold higher contents of muramic acid (marker of Gram-positive bacteria) and a sevenfold higher number of clones of animal-associated species, whereas in Finnish Karelian dust Gram-negatives (mainly Proteobacteria) predominated. Clones of plant-associated bacterial species and of chloroplast, indicating plant biomass, were more numerous in Finnish than in Russian Karelian dust. In conclusion, this study revealed major disparities between Finnish and Russian house dusts. The higher bacterial content and the predominance of Gram-positive bacteria in Russian dust may have implications for occurrence of atopy.

Serological Evidence of Thyroid Autoimmunity among Schoolchildren in Two Different Socioeconomic Environments

The mechanisms leading to thyroid autoimmunity are largely unknown. Our objective was to assess the role of environment in the development of thyroid autoimmunity. Prevalence of thyroid autoantibodies in two neighboring populations living in completely different socioeconomic circumstances (Russian Karelia and Finland) was studied. We studied two population-based cohorts partly sharing the same ancestry. A total of 532 schoolchildren from Russian Karelia and 532 schoolchildren in Finland matched for age, gender, and season of the blood sampling were included. There were no interventions. The prevalence of thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TGAb) and HLA-DQ alleles was measured. The prevalence of TPOAb was significantly lower in Russian Karelian than in Finnish children (0.4 vs. 2.6%, P=0.006). A similar difference was observed for TGAb (0.6 vs. 3.4%, P=0.002). Finnish girls tested positive for both TPOAb (4.3 vs. 0.4%, P=0.01) and TGAb (5.3 vs. 0.9%, P=0.01) more frequently than Finnish boys. Seven of the 23 tested subjects with signs of thyroid autoimmunity (30%) had increased serum TSH concentrations as a sign of subclinical hypothyroidism. The frequency of HLA genotypes did not differ between the two countries or between autoantibody-positive and -negative subjects. The prevalence of thyroid autoimmunity is lower in Russian Karelia than in Finland. This difference was not related to ethnic background or HLA-DQ alleles. The results support the idea that the Russian Karelian environment, which is characterized by inferior prosperity and standard of hygiene, may provide protection against thyroid autoimmunity.

Herpes simplex virus and atopy in Finnish and Russian Karelian children: Table 1—

To the Editors: Although the focus in the context of the hygiene hypothesis in explaining raised atopy prevalences has largely shifted from pathogens to commensals and saprophytes, the role of pathogens cannot be wholly ignored. Many pathogens are able to establish persistent or chronic infections, and have evolved strategies for immune evasion. A common immune subversion strategy used by such pathogens involves the increased production of the regulatory cytokines interleukin (IL)-10 and/or transforming growth factor-β by innate immune cells or via the generation of regulatory T (T-reg)-cells 1. These cytokines, by inhibiting/downregulating the function of antigen-presenting cells and effector T-cells, appear, in turn, to be crucial for the development of tolerance against allergens. We assessed whether seropositivities to three pathogens known to readily establish persistent/chronic infections (Helicobacter pylori, Toxoplasma gondii , herpes simplex virus (HSV)) and to hepatitis …

Allergic sensitization and microbial load – a comparison between Finland and Russian Karelia

Epidemiological data have indicated that some infections are associated with a low risk of allergic diseases, thus supporting the idea (hygiene hypothesis) that the microbial load is an important environmental factor conferring protection against the development of allergies. We set out to test the hygiene hypothesis in a unique epidemiological setting in two socio-economically and culturally markedly different, although genetically related, populations living in geographically adjacent areas. The study cohorts included 266 schoolchildren from the Karelian Republic in Russia and 266 schoolchildren from Finland. The levels of total IgE and allergen-specific IgE for birch, cat and egg albumen were measured. Microbial antibodies were analysed against enteroviruses (coxsackievirus B4), hepatitis A virus, Helicobacter pylori and Toxoplasma gondii. Although total IgE level was higher in Russian Karelian children compared to their Finnish peers, the prevalence of allergen-specific IgE was lower among Russian Karelian children. The prevalence of microbial antibodies was, in turn, significantly more frequent in the Karelian children, reflecting the conspicuous difference in socio-economic background factors. Microbial infections were associated with lower risk of allergic sensitization in Russian Karelian children, enterovirus showing the strongest protective effect in a multivariate model. The present findings support the idea that exposure to certain infections, particularly in childhood, may protect from the development of atopy. Enterovirus infections represent a new candidate to the list of markers of such a protective environment. However, possible causal relationship needs to be confirmed in further studies.

Circulating Vitamin D Concentrations in Two Neighboring Populations With Markedly Different Incidence of Type 1 Diabetes

Recent studies have suggested that vitamin D deficiency may increase the risk of type 1 diabetes (1). In Finland, the incidence of type 1 diabetes is the highest in the world, while in the neighboring Karelian Republic of Russia, the incidence is approximately one-sixth that in Finland, despite no difference in HLA-conferred susceptibility (2). Thus, the reason(s) must be linked to environmental factors. We assessed vitamin D status in the Russian Karelian and Finnish populations to determine whether vitamin D could play a role in the huge difference observed in diabetes incidence. The geographical location in terms of daily sunlight exposure is …

Isotopic composition of pyterlite in Vyborg (Viipuri), Wiborg batholith, Russia

Active worldwide research on rapakivi granites and related mafic and intermediate rocks has shown that this lithologic assemblage is an important tool in the study of the composition of deep continental crust and subcontinental mantle (see Haapala & Ramo 1999 and references therein). In any one area, the radiogenic isotope composition of the rapakivi granites reflects the overall age of the unexposed lithosphere that they occupy (e.g., Ramo 1991, Neymark et al. 1994, Ramo et al. 1995, Andersson 1997, Dall’Agnol et al. 1999). This has recently been particularly well established for the ~1.5 Ga rapakivi granites of central Sweden that show a substantial Archean source component although no Archean crust has been found to be exposed in that area (Andersson 1997). In the first part of the 1990’s, the rapakivi batholiths of Russian Karelia were studied for Nd and Pb (as well as Sr) isotopes that implied a mixed Archean-Paleoproterozoic source, in contrast to the clearly younger source characteristics of the rapakivi granites farther to the west in southern Finland (Ramo 1991, Neymark et al. 1994). The latter turned out to be quite homogeneous in terms of Nd and Pb isotopes with a clear Paleoproterozoic signature for all plutons extending from the Aland Islands in the west to the Finnish-Russian border in the east (Ramo 1991). The Russian Karelian rapakivi batholiths (Salmi and Ulyalegi; Fig. 1a) are situated at the contact zone of the Archean and Paleoproterozoic crustal domains of the Fennoscandian Shield and their mixed (Archean-Proterozoic) isotopic signature is thus quite understandable. Recent studies on the Mesoproterozoic (Amantov et al. 1996, Ramo et al. 2001a) Valamo dolerite of the Jotnian Lake Ladoga basin have suggested that a Neoarchean subcontinental lithosphere (with eNd [at 1.46 Ga] of ~ –9 and initial 87Sr/86Sr of ~0.705) probably underlies the north-central part of Lake Ladoga (Upton et al. 1998, Ramo et al. 2001a; Fig. 1). This suggests that the Archean-Proterozoic boundary may continue at depth farther to the southwest than the present exposed boundary northwest of Lake Ladoga (Fig. 1a). In order to examine whether the easternmost part of the Wiborg batholith in Russian Karelia (southwest of Lake Ladoga) records a major Archean source