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Sequences from first settlers reveal rapid evolution in Icelandic mtDNA pool
Agnar Helgason1, Carles Lalueza-Fox, Shyamali Ghosh
1deCODE Genetics, Reykjavik, Iceland. agnar@decode.is
Plos Genetics
|January 17, 2009
Summary
Ancient DNA reveals early Icelanders
Area of Science:
- Human genetics
- Population genetics
- Ancient DNA studies
Background:
- Understanding evolutionary processes shaping contemporary gene pools is a major task in human genetics.
- Ancient DNA offers insights into population evolution by sampling across time.
Purpose of the Study:
- To analyze mitochondrial DNA (mtDNA) control region sequences from early medieval Icelanders.
- To compare these ancient sequences with modern populations.
Main Methods:
- Mitochondrial DNA (mtDNA) control region sequencing.
- Comparative population genetics analysis.
Main Results:
- Sequences from 68 early medieval Icelandic skeletal remains showed greater similarity to contemporary Scottish, Irish, and Scandinavian populations than to modern Icelanders.
- This suggests early Icelandic settlers' mtDNA was better preserved in ancestral populations due to faster genetic drift in Iceland over 1,100 years.
Conclusions:
- Ancient DNA studies combined with population genetics analyses provide powerful insights into population evolutionary history.
- Genetic drift significantly impacted the Icelandic mtDNA pool, leading to divergence from ancestral sequences.
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