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Azores Islands: genetic origin, gene flow and diversity pattern
Claudia C Branco1, Marta São Bento, Cidália T Gomes
1Molecular Genetics and Pathology Unit, Hospital of Divino Espírito Santo, Ponta Delgada, São Miguel Island, Azores, Portugal.
Annals of Human Biology
|February 16, 2008
Summary
Genetic diversity in the Azores reveals a homogeneous population despite geographical isolation. Internal migration explains the lack of genetic differentiation across the nine islands.
Area of Science:
- Population Genetics
- Human Migration Studies
- Archipelago Demography
Background:
- The Azores archipelago comprises nine islands with distinct geographical and settlement histories.
- Understanding genetic diversity is crucial given the unique Azorean settlement patterns.
Purpose of the Study:
- To assess the genetic diversity and internal migration patterns of the Azorean population.
- To determine if geographical and historical factors have led to genetic differentiation among Azorean islands.
Main Methods:
- Analysis of 15 short tandem repeat (STR) loci.
- Study included 592 unrelated individuals from the nine Azorean islands.
Main Results:
- Gene diversity varied across islands, with Terceira highest (0.7979) and Corvo lowest (0.7717).
- Gene flow analysis indicated low migration into Corvo and high emigration from São Miguel and Terceira.
- Despite settlement differences, no significant genetic differentiation was observed among the islands today.
Conclusions:
- The Azorean population can be considered a genetically homogeneous group.
- This homogeneity suggests a uniform drug-reaction profile across the islands.
- Findings are significant for future genetic and pharmacogenomic studies in the Azorean population.
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