Genetic studies on Sami
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The Sami are regarded as an extreme outlier among European populations (Cavelli-Sforza 1994, Sajantila 1996, Tambets 2004) and their large genetic seperation from other European populations is best explained by assuming that the Sami are descendants of a narrow, distinctive subset of Europeans (Tambets 2004). Scenarios involving extremes of genetic drift, such as that due to repeated bottlenecks, could explain how the Sami mtDNA pool evolved as a narrow subset of that found in other European populations, likewise, it is possible that, when the proto-Sami gene pool was in statu nascendi, it was restricted to only a few basic mtDNA haplotypes that were carried by the founding settlers—a plausible scenario during the “Paleolithic isolation.” (Tambets 2004).
The early years
Already in the early years of genetic research the Sami people caught the scientists interest because of their unusual blood group distribution (Boyd 1939, Mourant 1952, Ryttinger 1957). The researchers found in the Sami populations the highest frequency of bloodgroup A2 observed in Europe and in the world. In later years the extension of more classical genetic markers did not enlighten any further the origin of the Sami (Beckman 1996).
Sami Autosomal DNA
The autosomal classic markers shows that the Sami have no close relatives in any population but are in general more closely related to Europeans than people of other continents (Cavalli-Sforza 1994, Niskanen 2002). The Sami are not more closely related to Siberian and Mongol populations than other European populations (Niskanen 2002) even their Scandinavian neighbours, in contrast to the historically held view that the Sami are of Siberian-Asiatic origin.
Sami mtDNA
The Sami people mtDNA haplogroup distribution strongly deviate from the distribution of other European countries including their closest neighbours (Tambets 2004). The European haplogroup Velda - V and haplogroup Ursula - subcluster, subclade U5b1b1 stands for 89.2% of the total haplogroups among the Sami people, while minor Siberian linages like D5 and Z occur at 4.4% (Tambets 2004). These major haplogroups occur widely at a very low rate in European populations except for the "Sami-specific motif" subset of haplogroup U5b in 12% of Finns (compared to 34% in Finnish Sami) in Finland's Oulu Province to Sami admixture (Meinilä 2001) and haplogroup V among the Basque people (12.4%) and Pasiego people (18.6%)in Iberian Peninsula [citation needed],and Mari people in Volga-Ural (10.2%). (Finns in the more northern Lapland Province were not studied because recent maternal Sami ancestry could not be ruled out.) Further almost 50% of haplogroup U5b1b1 HVR1 haplotypes are unique for the Sami people population and do not occur elsewhere, while most of the haplogroup V HVR1 haplotypes is also seen among other European populations (Torroni 2001). The age of haplogroup U5b1b1 was estimated by Delghandi 1998 using HVR1 haplotypes only to be between 5 500 to 10 500 years old, and by Ingman 2006 using full mtDNA sequences haplogroup U5b1b1 and V was estimated to be 5 500 and 7 500 years old respectively. It is believed on the basis of correlation analysis that haplogroup V and U5b migrated togheter with male haplogroup I1a (Rootsi 2004) and on the basis of variance and haplotype analysis its believed they migrated from western Europe.
Sami Y-chromosome
Sami Y chromosomes haplogroup distribution is similar to the Finns and Estonians with haplogroup N3, I1a and R1a as major haplogroups (Tambets 2004). Haplogroup I1a is common among all neighbouring populations (Dupuy 2005, Karlsson 2006, Lappalainen 2006, Tambets 2004). Haplogroup N3a is common among the Finns, while haplogroup R1a is common among all the neightbours except the Finns (Lappalainen 2006). Haplogroup R1a in Sami is mostly seen in the Swedish Sami and Kola Sami populations (Tambets 2004). However an analysis of the microsatelites substructure of haplogroup I1a and N3a among the East-Sami reveals that Finns and Estonians are a unlikely source of recent contributions, (Raitio 2001) while the Jokkmokk Saami in Sweden have similar structure as among Swedes and Finns for haplogroup I1a and N3 (Karlsson 2006).
See also
References
External links
- Mitochondrial DNA Diversity in Europe, Sajantila 1995
- Genes and Languages in Europe: An Analysis of Mitochondrial Lineages, Sajantila 1995
- The genetic relationship between the Finns and the Finnish Saami (Lapps): analysis of nuclear DNA and mtDNA, Lahermo 1996
- Saami Mitochondrial DNA Reveals Deep Maternal Lineage Clusters, Delghandi 1998
- Geographic Patterns of mtDNA Diversity in Europe, Simoni 2000
- Evidence for mtDNA admixture between the Finns and the Saami, Meinilä 2001
- Y-Chromosomal SNPs in Finno-Ugric-Speaking Populations Analyzed by Minisequencing on Microarrays, Raitio 2001
- The Origin of the Baltic-Finns from the Physical Anthropological Point of View, Niskanen 2002
- The Western and Eastern Roots of the Saami—the Story of Genetic “Outliers” Told by Mitochondrial DNA and Y Chromosomes, Tambets 2004
- Saami and Berbers—An Unexpected Mitochondrial DNA Link, Achilli 2005
- A recent genetic link between Sami and the Volga-Ural region of Russia, Ingman 2006