Genetic Insights Reveal Connection Between Blood Clots and Long COVID
Recent genetic research has unveiled a fascinating link suggesting that individuals who are genetically predisposed to forming blood clots may face an elevated risk of developing long COVID. This intriguing finding bolsters the hypothesis that irregular clotting processes could be contributing to the persistence of symptoms following a SARS-CoV-2 infection.
In what stands as one of the most extensive genetic investigations into long COVID to date, scientists discovered that specific genetic variations associated with venous thromboembolism—conditions linked to blood clots in the veins—are also correlated with a greater probability of experiencing long-term symptoms post-COVID. Notably, these associations were found to be independent of the severity of the initial COVID-19 infection.
Investigating Genetic Risk Factors for Clotting
Long COVID manifests through a diverse array of symptoms impacting various organs, including debilitating fatigue, shortness of breath, and cognitive difficulties—often lasting weeks or even months following the acute phase of the infection. While some theories have pointed to ongoing inflammation and damage to small blood vessels as potential underlying causes, concrete evidence demonstrating these mechanisms in humans has been sparse.
To shed light on this issue, researchers delved into data from the Long COVID Host Genetics Initiative, which included a cohort of 3,018 individuals suffering from long COVID alongside nearly one million control participants. The focus was on determining whether genetic markers known to elevate the risk of venous thromboembolism also corresponded with instances of long COVID. By employing genetic risk scores, the team was able to assess an individual's lifelong susceptibility to clotting, thus minimizing the impact of other confounding factors that often challenge observational studies.
The Findings: A Clear Connection
The results uncovered a robust correlation between the risk of blood clotting and the likelihood of developing long COVID. Specifically, each unit increase in genetically predicted venous thromboembolism risk translated to a striking 21% rise in the odds of experiencing long COVID symptoms. This association was statistically significant, boasting a 95% confidence interval ranging from 1.08 to 1.35 and a P value of 1.2 × 10⁻³.
Crucially, the findings remained consistent regardless of the severity of the acute COVID-19 illness, indicating that mechanisms related to clotting could play a role in long COVID even among those who did not endure a severe initial episode. These results were further validated through multiple sensitivity analyses and replicated in external datasets, reinforcing the reliability of the conclusions drawn.
Reference
Schuermans A et al. Human genetics implicate thromboembolism in the pathogenesis of long COVID in individuals of European ancestry. 2025;4:1662-76.
Author
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So, what do you think about the relationship between genetic predispositions and long COVID? Is it possible that our genes could hold the key to understanding this complex condition? Feel free to share your thoughts and join the conversation!
