Genetic studies on Sami

Since the early years of genetic research, the Sami people have caught the interests of scientists. The Sami languages belong to the Uralic languages family of Eurasia.

Siberian origins are still visible in the Sámi, Finns and other populations of the Finno-Ugric language family.

“However, it has been mixed up with the European genome. Of all European populations, modern Sámi are the most evident representatives of the Siberian genome. As for the title of the modern people with the largest Siberian genetic component, that privilege goes to the Nganasan people living in northern Siberia,” says Päivi Onkamo, head of the SUGRIGE project at the Universities of Helsinki and Turku.

An abundance of genes has journeyed all the way from Siberia to Finland, a recent study indicates. As late as during the Iron Age, people with a genome similar to that of the Sámi people lived much further south in Finland compared to today. The first study on the DNA of the ancient inhabitants of Finland has been published, with results indicating that an abundance of genes reached Finland all the way from Siberia.

Genetic material from Siberia has been found in the inhabitants of the Kola Peninsula from as far back as approximately 4,000 years ago, later spreading also to Finland. The study also corroborates the assumption that people genetically similar to the Sámi lived much further south in Finland than today even during the Iron Age.

The genetic samples compared in the study were collected from human bones found in a 3,500-year-old burial place in the Kola Peninsula and the 1,500-year-old lake burial site at Levänluhta in South Ostrobothnia, Finland. All of the samples contained identical Siberian genes.

Y-DNA

Three Y chromosome haplogroups dominate the distribution among the Sami: N1c (formerly N3a), I1 and R1a at least in the study carried out by K. Tambets et al. in 2004. The most common haplogroup among the Sami is N1c, with I1 as a close second according to that study. Haplogroup R1a in Sami is mostly seen in the Swedish Sami and Kola Sami populations, with a low level among the Finnish Sami. Tambets and colleagues suggested that N1c and R1a probably reached Fennoscandia from eastern Europe, where these haplogroups can be found in high frequencies.[1]

However the two haplogroups have a distinctly different linguistic distribution. R1a1a is common among Eastern Europeans speaking Indo-European languages, while N1c correlates closely with the distribution of the Finno Ugrian languages. For example, N1c is common among the Finns, while haplogroup R1a is common among all the neighbours of the Sami.[2]

Haplogroup I1 is the most common haplogroup in Sweden, and the Jokkmokk Sami in Sweden have similar structure to Swedes and Finns for haplogroup I1 and N1c. Haplogroup I-M253 in Sami is explained by immigration (of men) during the 14th century.[3] That is quite late in Sami history bearing in mind that an distinctive Sami culture can be traced and first observed back to 1000 BC.[4]

The Sami languages have been reckoned to have split from their common ancestor as recently as 1300 years ago.[5]

mtDNA

Classification of the Sami mtDNA lineages revealed that the majority are clustered in a subset of the European mtDNA pool. The two haplogroups V and U5b dominate, between them accounting for about 89% of the total. This gives the Sami regions the highest level of Haplogroups V and U5b thus far found. Both haplogroups V and U5b are spread at moderate frequencies across Europe, from Iberia to the Ural Mountains. Haplogroups H, D5 and Z represent most of the remaining averaged total. Overall 98% of the Sami mtDNA pool is encompassed within haplogroups V, U5b, H, Z, and D5. Local frequencies among the Sami vary.[1]

The divergence time for the Sami haplogroup V sequences was estimated by Max Ingman and Ulf Gyllensten at 7600 YBP (years before present), and for U5b1b1 as 5500 YBP amongst Sami and 6600 YBP amongst Sami and Finns. This suggests to them an arrival in the region soon after the retreat of the glacial ice.[6]

Other research on Sami shows that most of them do not belong to the mtDNA Haplogroup I[7] (not to be confused for the aforementioned paternal Haplogroup I-M170) that is shared by many Finnic peoples.

U5b

Although a small proportion of the Haplogroup U (mtDNA) among the Sami falls into U4, the great majority is U5b. The percentage of total Sami mtDNA samples tested by K. Tambets and her colleagues (published in 2004) which were U5b ranged from 56.8% in Norwegian Sami to 26.5% in Swedish Sami.[1]

In research made by M. Ingman and U. Gyllensten in 2006 shows a slightly different setting: Norwegian Sami belongs to U5b as well as U5b1b1 to 56.8%, Finnish Sami with 40.6%, Northern Sami in Sweden to 35.5% and Southern Sami in Sweden within reindeer herding to 23.9% while Southern Sami in Sweden outside of reindeer herding/other occupation belong to U5b to 16.3% and to U5b1b1 to 12%.[8]

Sami U5b falls into subclade U5b1b1. The Sami U5b1b1 [1] sub-clade is present in many different populations, e.g. 3% or higher frequencies in Karelia, Finland, and Northern-Russia.[1] The Sami U5b1 motif is additionally found in very low frequencies for instance in the Caucasus region, however this is explained as recent migration from Europe.[9] However 38% of the Sami U5b1b1 mtDNAs have haplotype so far exclusive to the Sami, containing a transition at np 16148.[1]

Alessandro Achilli and colleagues noted that the Sami and the Berbers share U5b1b, which they estimated at 9,000 years old, and argued that this provides evidence for a radiation of the haplogroup from the Franco-Cantabrian refuge area of southwestern Europe.[10]

V

The divergence time for the Sami haplogroup V sequences is estimated by Max Ingman and Ulf Gyllensten at 7.600 years ago. But there is a difference within the Sami group in Sweden according to their study. North Sami (Sami in the North of Swedish Lapland) belong to haplogroup V with 58.6% and South Sami (Sami in the South of Swedish Lapland) within reindeer herding to 37.0% and South Sami outside reindeer herding/other occupation to 8.7%. That can be compared with Sami in Norway that has a 33.1% belonging to haplogroup V and Sami in Finland to 37.7%. Sami in Finland and South Sami in Sweden has the same percentage belonging to haplogroup V.[6]

But according to K. Tambets' et al. study is haplogroup V the most frequent haplogroup in the Swedish Sami and is present at significantly lower frequencies in Norwegian and Finnish subpopulations.[1]

Torroni and colleagues have suggested that the spread of haplogroup V in Scandinavia and in eastern Europe is due to its late Pleistocene/early Holocene expansion from a Franco-Cantabrian glacial refugium.[11]

However subsequent studies found that haplogroup V is also significantly present in eastern Europeans. Furthermore, haplogroup V lineages with HVS-I transitions 16153 and 16298 that are frequent in the Sami population are much more widespread in eastern than in western Europe. So haplogroup V might have reached Fennoscandia via central/eastern Europe. Such a scenario is indirectly supported by the absence, among the Sami, of the pre-V mtDNAs that are characteristic of southwestern Europeans and northwestern Africans.[1]

Z

Haplogroup Z is found at low frequency in the Sami and Northern Asian populations but is virtually absent in Europe. Several conserved substitutions group the Sami Z lineages with those from Finland and the Volga-Ural region of Russia. The estimated dating of the lineage at 2700 years suggests a small, relatively recent contribution of people from the Volga-Ural region to the Sami population.[6]

See also

Notes

    References
    1. Kristiina Tambets; Siiri Rootsi; Toomas Kivisild; Hela Help; Piia Serk; et al. (2004). "The Western and Eastern Roots of the Saami—the Story of Genetic "Outliers" Told by Mitochondrial DNA and Y Chromosomes" (PDF). American Journal of Human Genetics. 74 (4): 661–682. doi:10.1086/383203. PMC 1181943. PMID 15024688.
    2. Tuuli Lappalainen; Satu Koivumäki; Elina Salmela; Kirsi Huoponen; Pertti Sistonen; Marja-Liisa Savontaus; Päivi Lahermo (2006). "Regional differences among the Finns: A Y-chromosomal perspective". Gene. 376 (2): 207–215. doi:10.1016/j.gene.2006.03.004. PMID 16644145.
    3. Andreas O Karlsson, Thomas Wallerström, Anders Götherström and Gunilla Holmlund (2006). "Y-chromosome diversity in Sweden – A long-time perspective". European Journal of Human Genetics. 14 (8): 963–970. doi:10.1038/sj.ejhg.5201651. PMID 16724001.CS1 maint: multiple names: authors list (link)
    4. Lars Ivar Hansen and Bjørnar Olsen, Hunters in Transition: An Outline of Early Sámi History, The Northern World: North Europe and the Baltic c. 400–1700 AD. Peoples, Economics and Cultures, 63 (Leiden: Brill, 2014), p. 14 ISBN 978-90-04-25254-7.
    5. Václav Blažek, "Uralic Migrations: The Linguistic Evidence".
    6. Max Ingman; Ulf Gyllensten (2007). "A recent genetic link between Sami and the Volga-Ural region of Russia". European Journal of Human Genetics. 15 (1): 115–120. doi:10.1038/sj.ejhg.5201712. PMID 16985502.
    7. Ingman, Max; Gyllensten, Ulf (20 September 2006). "A recent genetic link between Sami and the Volga-Ural region of Russia". European Journal of Human Genetics. 15 (1): 115–120. doi:10.1038/sj.ejhg.5201712. ISSN 1018-4813. PMID 16985502.
    8. http://www.nature.com/ejhg/journal/v15/n1/fig_tab/5201712t1.html#figure-title
    9. Martin Richards; et al. (2000). "Tracing European Founder Lineages in the Near Eastern mtDNA Pool" (PDF). American Journal of Human Genetics. 67 (5): 1251–1276. doi:10.1016/S0002-9297(07)62954-1. PMC 1288566. PMID 11032788.
    10. Achilli, Saami and Berbers (2005). "An Unexpected Mitochondrial DNA Link". American Journal of Human Genetics. 76 (5): 883–886. doi:10.1086/430073. PMC 1199377. PMID 15791543.
    11. A. Torroni; et al. (2001). "A signal, from human mtDNA, of postglacial recolonization in Europe". American Journal of Human Genetics. 69 (4): 884–885. doi:10.1086/323485. PMC 1226069. PMID 11517423.

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    Further reading
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