New study: Mothers on the move – thousands of complete mitochondrial sequences reveal the layered formation of the common maternal genepool of Finland and Estonia.

Here my summary of the study (-> link ).

Shared mtDna:

• The study found that a substantial portion of mtDNA sequences (around 40% in Finland and 15% in Estonia) belong to monophyletic clusters shared between the two countries, indicating a long-standing genetic connection.
•  Temporal and Concurrent Structure:

  These shared lineages are not randomly distributed but show a temporal structure, with different layers corresponding to different periods, from the Late Neolithic to the Middle Ages.
• Migration Patterns:

  The research associates some of these mtDNA lineages with the movement of people, as evidenced by archaeological findings and studies on Y-chromosome and ancient DNA.
• Languages:

  The study also notes an increase in the maternal effective population size during the Iron Age, coinciding with the diversification time of Finnic languages, suggesting a link between language and genetic history.
• Homogeneity Notion:

  Unlike the general perception of a relatively homogenous European mitochondrial genepool, this study reveals a geographic pattern in mtDNA distribution, particularly when considering related populations like Finland and Estonia.
• Limited Shared Lineages with Sweden:

  Despite geographic proximity and historical Swedish settlements, only a small percentage of mtDNA sequences in both Finland and Estonia form common clusters with Sweden (8% in Finland and only 2% in Estonia), indicating a more significant genetic contribution from other sources.