A research team from the Institut de Biologia Evolutiva (IBE), a collaborative center of the Consejo Superior de Investigaciones Científicas (CSIC) and the Universitat Pompeu Fabra (UPF) in Barcelona, has determined that the geography of the Iberian Peninsula has not influenced the genetic adaptations of the Spanish population. The findings indicate that the majority of genetic adaptations present in Spaniards are also found in other European groups, with no distinct set of adaptations unique to the Iberian Peninsula, as stated by IBE in a recent announcement.
In this study, over 800 genomes from residents of Catalonia, aged between 40 and 60, were analyzed as part of the GCAT project. The aim was to explore how historical migrations may have impacted the genetic adaptations of native populations. The analysis sought to identify variations from an average Iberian genomic profile, which consists of 5-10% genetic material from hunter-gatherers dating back over 6,000 years, 55-60% from Anatolian farmers, and 35-40% attributable to a migration of nomads from the Steppes around 4,000 years ago.
The researchers noted that potential adaptive variants may be concealed behind differences from the average genomic profile. However, the results revealed a significant number of shared adaptations with other European populations, a consequence of extensive migrations throughout European history. Participants displayed a typical European genetic profile with a small proportion of North African ancestry, which is predominantly found in the Iberian Peninsula, southeastern France, and Sicily.
The team also investigated the impact of the 16th-century French diaspora, which emerged from the Wars of Religion. Despite these immigrants constituting a quarter of the Catalan population at one point, the study did not uncover any specific genetic footprint linked to this group.
Among the discoveries were new genetic variants with adaptive significance in contemporary Europeans. Notable examples include the SMYD1 gene, which may enhance resistance to influenza, and the FDFT1 gene, associated with cholesterol metabolism. Additionally, adaptive signals were identified in the UBL7 gene, linked to immune response, and the rs55852693 polymorphism, which is correlated with a heightened preference for spicy foods. Furthermore, the study reaffirmed several well-characterized adaptations found in European populations, such as lighter skin, lactose digestion capabilities, and specific traits related to immune response.
