This page is a guide to the genetics of the ethnic Finns of Finland and Norway (they are called Kvens in the latter country), not the Karelians of northwestern Russia.

The Finnish language is in the Finnic sub-group of the Finno-Ugric branch of Uralic languages. Of all languages in the world, Finnish is most similar to Karelian and Estonian, but farther from Sami and other Uralic languages.

Family Tree DNA's "Finland DNA Project" includes some people who aren't true Finns, but among participants who are ethnic Finns their Y-DNA haplogroups include A-M31, E-M35, E-V13, I-M170, I-M253, I-L258, I-BY2572, L813, N-M231, N-L1022, N-CTS10082, N-Z5893, N-Z1940, N-CTS8445, R-M198, and other haplogroups. Among all project members, haplogroups within N (of eastern origin) are the most common overall with around 59-60% of male members in that, followed by I1 representing about 30% of male members, R1a held by about 3%, R1b by 3%, and the rest including E, J, and Q. Only about 1% of Finnish men have E1b1b1, from Neolithic Farmers from further south in West Asia.

Scientists believe the Y haplogroup N1c originated in Asia and entered Europe between 12,000 and 14,000 years ago. N1c is found not only among Finns but also among natives of Estonia, Latvia, Lithuania, and Russia. N1c is particularly commonplace among Finnic and Uralic speakers of northeastern Europe whom besides Estonians include Maris, Mordvins, Udmurts, and Komis. N1c1 is a subclade that's especially common among Finns, Estonians, and Sami but also found among Norwegians.

On the mtDNA side, members of the "Finland DNA Project" belong most often to the mtDNA haplogroups H (about 40%) and U (about 30%). The remainder belong to a medley of D, I, J, HV, R, T, V, W, X, and Z. Finns' mtDNA haplogroups are overwhelmingly European rather than Asian. Haplogroup W is more common among Finns than among populations in the rest of Europe. According to National Geographic's Genographic Project, Finns, Estonians, and Samis are known for having high levels of haplogroup U5 compared to other Europeans. Among Finnish customers of 23andMe, an example of one of their mtDNA subclades of H is H1f.

Overall, as we know from autosomal studies, Finnish ancestry derives primarily from Europe, especially the Baltic region, and only in small amounts from Siberia (North Asia), less Siberian than Samis have.

According to "The ALlele FREquency Database" compiled by Kenneth K. Kidd of Yale University, between 3 and 6 percent of Finns have the 1540C allele on their EDAR (Ectodysplasin A receptor) gene. This allele originated in East Asia and is uncommon in most of Europe except among peoples with some East/North Asian ancestry like Hungarians and Ashkenazim.

Finns aren't closely related to the Sami people, autosomally. Of all populations, Finns are closest to Estonians followed by Swedes.

There are noteworthy autosomal and uniparental differences between Eastern Finns and Western Finns. Eastern Finns have more (5-10%) of a pull in the direction of North Asia than Western Finns (3-4%) do, and their haplogroup distributions are different.