The genetic map of education and IQ in Spain
Polygenic scores and Spain's regional educational divide
Spain’s regional disparities are economic as well as educational. In 2024, GDP per person was €41,016 in the Basque Country and €39,076 in Navarre, compared with €24,566 in Andalusia and €25,227 in Extremadura; the national figure was €32,633. Madrid, at €44,755, is the conspicuous capital-city exception to any simple north–south gradient.
The educational divide has similar geography. In PISA 2022 mathematics, Castile and León scored 499 points, compared with 457 in Andalusia and 447 in the Canary Islands: a 52-point span between the highest and lowest participating autonomous communities. Castile and León also led reading with 498 points, 37 above Andalusia’s 461, while Castile and León and Galicia scored 506 in science, 33 above Andalusia and the Canary Islands at 473. Northern Spain does not uniformly outperform southern Spain—regional history, language, urbanisation, and internal migration prevent such a clean partition—but the broad gradient is clear.
Italy provides a direct comparison. INVALSI’s PISA 2022 report gives mathematics means of 500 in the North West and 496 in the North East, against 434 in the South and 441 in the South and Islands. The corresponding north–south differences range from 55 to 66 points, roughly one PISA proficiency level. Spain’s regional gap is therefore similar in direction and order of magnitude, although the Italian divide is larger and is reported for broad macro-areas rather than individual regions.
Two earlier analyses on this newsletter provide the immediate background. Italy’s North–South divide: what genome-wide similarity misses reported that the EA4 polygenic score was lower in southern than in northern and central Italy, with a North–South effect size of Hedges g = 0.66.
The goal of this study is to test whether an analogous pattern can be detected with individual genomic data and several independent educational assessments. Do regional differences in modern Spanish genetic structure, summarized by polygenic scores, covary with the country’s educational geography? The analysis compares autonomous-community averages for two educational-attainment polygenic scores with PISA 2022 and two Spanish national diagnostic assessments.
