Structuring the genetic heterogeneity of the Basque population: a view from classical polymorphisms

Area of Science:

• Population Genetics
• Human Genetics
• Anthropology

Background:

• The Basque population is of significant interest due to its unique linguistic and cultural history.
• Understanding the genetic structure of the Basque people can provide insights into historical migration patterns and population dynamics in Western Europe.

Purpose of the Study:

• To analyze genetic variation across 18 classical polymorphisms in autochthonous Basque individuals.
• To investigate the genetic heterogeneity and population structure within the Basque Country.
• To assess the influence of historical, geographical, and cultural factors on Basque genetic diversity.

Main Methods:

• Analysis of 18 classical polymorphisms in over 2000 individuals from 14 districts across three Basque provinces.
• Heterogeneity analysis using the chi-squared test and F(ST) calculations.
• Assessment of allele distribution patterns using Moran's autocorrelation coefficient I and considering geographical and historical factors.

Main Results:

• Significant genetic heterogeneity was detected among Basque districts, distributed across provinces rather than concentrated in specific areas.
• Allele distribution exhibits a geographical pattern, with evidence of gene flow towards the coast influenced by major historical travel routes.
• While some factors like administrative division and linguistic heterogeneity showed limited influence, ancient tribal differentiation (2000 B.P.) had a discernible, albeit diminishing, impact.

Conclusions:

• The Basque population displays significant fine-scale genetic structure, with allele frequencies influenced by geography and historical migration.
• Gene flow appears to be directed towards the coast, shaped by ancient travel routes.
• Historical factors, including tribal differentiation, have played a role in shaping the current genetic landscape of the Basque Country.