A study led by the Higher Council for Scientific Research (CSIC) has identified a common genetic variant associated with a increased risk of developing severe covid-19. This variant, present approximately in one in five peopleaffects the body’s initial response to the virus and can facilitate a more intense inflammation during infection.
The research, recently published in the scientific journal iSciencehelps explain one of the great unknowns left by the pandemic: why some young people, with no known previous pathologies, developed very serious symptoms of covid-19while in most cases the disease was mild.
The role of the OAS1 gene in the response to the virus
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The work focuses on the gene OAS1involved in a path of innate antiviral defense which allows cells to detect the genetic material of the virus SARS-CoV-2 and activate an early response to stop its replication. Under normal conditions, this pathway acts as a first mechanism to contain the infection.
Researchers have identified a heritable polymorphismknown as rs10774671which reduces the effectiveness of this initial response. When a person inherits two copies of this variant, their body produces a less efficient form of the OAS1 protein, which results in a decreased ability to limit virus replication in the early stages of infection.
The risk increases, but does not determine the clinical evolution
Although this variant increases the probability of developing severe covid-19, the authors emphasize that does not determine by itself the evolution of the disease. Factors like the agehe sex o to ethnicity They also significantly influence the clinical response.
“Having this polymorphism does not necessarily imply that a severe form of the disease will develop,” explains the researcher. Jordi Pérez-Tur. According to the authors, the genetic factor acts as a risk modulatornot as a single cause.
Genetic analysis and experiments in animal models
To reach these conclusions, the team analyzed genetic samples of 342 patients between 18 and 65 years old who had had the infection. The study combined genome sequencing with experiments on human cells and with animal models genetically modified.
The results in animals showed that the absence of certain genes related to this antiviral pathway is associated with a more intense inflammatory responsecharacterized by an increase in cytokinesmolecules that, in excess, can cause uncontrolled inflammation.
Understanding genetics for future health emergencies
The authors highlight that understanding how genetics influence response to coronavirus It is key to identifying vulnerability factors and guiding prevention strategies against future health emergencies. This polymorphism, ancient evolutionary origindoes not make those who carry it especially vulnerable people, but it does help to better understand the diversity of responses to the same infection.
The study has had the participation of research centers and hospitals, including the Institute of Biomedicine of Valencia (CSIC)he General University Hospital of Alicante and the La Fe Hospital in Valenciain addition to public and European financing.
date:2026-02-13 23:00:00