Mitochondrial DNA Distribution in Southern Iberia

Dec 17, 2024

Lecture Notes: Distribution of Mitochondrial DNA Haplogroup H in Southern Iberia

Background

  • Haplogroup H exhibits differences across the Mediterranean and between northern and southern regions.
  • Western Mediterranean populations have high frequencies of haplogroup H.
  • Study aims to explore ancient migrations and genetic exchanges between Iberia and North Africa.

Study Design

  • Sample: 750 individuals from Huelva and Granada in Southern Iberia.
  • Methods: High-resolution analysis of haplogroup H via sequencing and SNP screening.
  • Comparison: Results compared with other Mediterranean populations including Iberia and Maghreb.

Key Findings

Genetic Structure and Diversity

  • Andalusian subpopulations have a typical Western European haplogroup H profile.
  • Eastern Andalusians from Granada show traces of Eastern Mediterranean influences.
  • Haplogroups H1 and H3 are prevalent, indicating ancient connections.

Phylogeographic Analysis

  • Haplotypes shared more frequently between Andalusia and Morocco.
  • Strait of Gibraltar was not a barrier; instead, a route for ancient migrations.
  • Spatial structure observed across the Mediterranean, decreasing eastward.

Population Comparisons

  • Western and Eastern Mediterranean populations show significant genetic differences.
  • Iberian Peninsula acts as both a genetic sink and source between Africa and Europe.

Phylogenetic and Statistical Analysis

  • Use of hierarchical cluster analysis and AMOVA to assess population structure.
  • Haplogroup H indicates post-glacial expansions from Iberian refuges.

Implications

  • Ancient migrations likely occurred using maritime routes across the Mediterranean.
  • Genetic data supports archaeological evidence of prehistoric connections between Iberia and Africa.

Methods Summary

  • Samples sourced from volunteer donors with informed consent.
  • Analysis included sequencing and genotyping of specific SNPs.
  • Data compared to a comprehensive dataset of Mediterranean populations.

Conclusion

  • Western Mediterranean was an active zone for genetic exchange.
  • The study reinforces the significance of maritime connectivity in prehistoric times.

Additional Information

  • Data included in the study is open access and available in GenBank.
  • Research was ethically approved with participant consent.

These notes provide an overview of the key points and findings discussed in the lecture on the distribution of mitochondrial DNA haplogroup H in Southern Iberia, highlighting the genetic exchanges along the western Mediterranean.