Nearly 700,000 people's DNA has just revealed why anxiety affects us so differently—and researchers at King's College London have uncovered 74 genetic locations linked to anxiety symptoms, with 39 of them never before identified. This latest genome-wide association study, published in Nature Human Behaviour, represents the largest genetic investigation into anxiety to date, offering hope that we're finally closing a major gap in mental health science.
Anxiety disorders remain the most prevalent mental health conditions worldwide, and their prevalence is rising, particularly among young adults. Yet despite the enormous public health burden, understanding the genetic foundations of anxiety has lagged significantly behind research into other major mental health conditions. The new study changes that by taking a subtler approach: rather than sorting people into a simple yes-or-no clinical diagnosis, researchers linked genetic data to the actual severity of anxiety symptoms. This reveals how anxiety exists on a biological spectrum, ranging from normal, protective stress responses to debilitating disorder—a nuance that better reflects how anxiety actually appears in the real world.
The research team, led by Professor Thalia Eley at King's College London's Institute of Psychiatry, Psychology & Neuroscience, analyzed genetic differences across 693,869 people of European ancestry. The breakthrough included strong evidence for the role of specific genes like PCLO and SORCS3 in anxiety risk. Many of the genes implicated in the study are particularly active in brain tissue and are involved in how nerve cells communicate with each other—pointing toward biological pathways that may influence how our brains respond to threat and uncertainty.
Yet the findings come with a crucial humility. Common genetic variation explains only around 6% of the differences in anxiety symptom severity between people, leaving the majority of the picture shaped by environmental influences, life experiences, and the complex ways genes interact with our circumstances. This reality matters deeply: someone with high genetic risk may never develop anxiety if their environment supports them, while someone with low genetic risk could develop it under sufficient stress. The rising anxiety rates across populations point unmistakably to environmental factors, since genetics don't shift significantly across generations.
Dr. Megan Skelton, first author of the study, emphasized this interconnection. "Genetics interplay with life experiences, social contexts and psychological factors to shape individual risk," she explained, highlighting that reducing anxiety population-wide will require addressing environmental factors alongside biological insights. Understanding genetic risk, however, offers a practical path forward: it could help identify people who are particularly sensitive to environmental influences, enabling more targeted and effective prevention and treatment strategies.
The researchers also calculated polygenic risk scores—summaries of each individual's genetic vulnerability—across different population groups. These scores explained between 1.2% and 2.9% of variance in anxiety severity, providing some support for shared genetic influences across European, African, and South Asian populations. Yet the results also underscored an important limitation: ancestry-specific research remains essential, as different populations carry distinct genetic patterns. As large-scale research expands globally, the hope is that this work will spark a new generation of anxiety genetics studies, ultimately enabling us to support people more effectively by addressing both the biological and environmental dimensions of their risk.