A genetic analysis of nearly 700,000 people has identified 74 regions of the human genome linked to anxiety symptoms, including 39 that had never before been associated with the condition, giving scientists their most detailed picture yet of the biology behind one of the world’s most common mental health disorders.The international study, published in Nature Human Behaviour, was led by researchers from King’s College London and Australia’s QIMR Berghofer Medical Research Institute. It analysed genetic information from 693,869 people of European ancestry, making it the largest genome-wide association study (GWAS) ever conducted on anxiety.Researchers say the unprecedented scale of the study enabled them to detect genetic signals that smaller investigations had missed. Rather than uncovering a single “anxiety gene”, they identified dozens of tiny genetic variations that together influence a person’s susceptibility to anxiety.
Largest genetic study of anxiety to date
Although anxiety disorders affect hundreds of millions of people worldwide, scientists have known far less about their genetic basis than other psychiatric conditions such as depression and schizophrenia.The new research nearly doubled the size of previous anxiety GWAS studies, allowing researchers to uncover many more genetic links simply because the dataset was much larger.Genome-wide association studies scan the DNA of hundreds of thousands of people to identify genetic variations that occur more frequently in people with a particular trait or condition. Because psychiatric disorders are influenced by many genes, each with only a very small effect, researchers need enormous datasets before those signals become statistically reliable.The result is the most comprehensive genetic map of anxiety produced so far.“Despite the public health impact of anxiety, progress in the understanding of its genetics lags behind other major mental health conditions.”Professor Thalia Eley of King’s College London, the study’s senior author, said anxiety has received far less attention in genetic research despite being the most common category of mental illness worldwide.
Looking at symptoms instead of diagnosis
One reason this study uncovered more genetic regions than earlier research lies in how anxiety was measured.Instead of separating participants into those with or without a diagnosed anxiety disorder, researchers measured anxiety symptom severity across the entire population. This allowed them to include people experiencing everything from everyday anxiety to severe clinical symptoms.The researchers say many people experience significant anxiety without ever receiving a formal diagnosis. By treating anxiety as a continuous spectrum rather than a simple yes-or-no diagnosis, they retained far more genetic information.That decision appears to have paid off. Earlier diagnosis-based studies identified roughly three dozen genetic regions linked to anxiety. This study found 74.
Key genes linked to brain activity
Among the strongest findings were two genes, PCLO and SORCS3, both previously associated with other psychiatric disorders.These genes help regulate communication between nerve cells at synapses, where brain cells exchange signals. Many of the newly identified genetic regions are also located near genes that are highly active in brain tissue.The findings reinforce the idea that anxiety is not caused by a single faulty gene. Instead, hundreds of small genetic influences appear to work together alongside environmental factors such as stress, trauma and life experiences.In other words, there is no single genetic switch for anxiety. Each variant contributes only a small increase in risk.
Shared genetics with physical illnesses
Researchers also discovered significant genetic overlap between anxiety and several physical health conditions, including heart disease, migraine and digestive disorders.They stress that this does not mean anxiety causes these illnesses, or vice versa. Rather, some of the same genetic variations appear to increase the likelihood of developing both anxiety and certain physical conditions.Doctors have long observed that people with anxiety frequently experience migraines, cardiovascular symptoms or conditions such as irritable bowel syndrome. The study offers new biological clues that may help explain why these conditions often occur together.Scientists believe these shared genetic pathways could become an important focus for future research.
What the findings actually mean
While the study represents a major advance, researchers caution against overstating its immediate clinical impact.Common genetic variations explained only about 6 per cent of differences in anxiety symptom severity across the population. Polygenic risk scores built using the new data accounted for up to 2.9 per cent of that variation individually.That means the findings are valuable for understanding anxiety biology but cannot accurately predict whether a specific individual will develop the condition.Researchers emphasise that environment, childhood experiences, trauma, stress and other life factors continue to play a much larger role in determining a person’s mental health.The study does not pave the way for a genetic test that can reliably predict anxiety. Instead, it provides scientists with a far clearer roadmap for understanding the biological processes involved.
A growing global burden
The findings come as anxiety disorders continue to affect an increasing number of people worldwide.Researchers estimate that 359 million people were living with anxiety disorders in 2021, around 4.4 per cent of the global population. That figure is projected to exceed 515 million by 2040, with cases rising faster than population growth alone.Despite its widespread impact, treatment remains inaccessible for many people. In many high-income countries, fewer than one in three people with an anxiety disorder receives treatment, while access is even more limited in lower-income nations.Even when treatment is available, it does not work for everyone.Most medicines currently prescribed for anxiety, including selective serotonin reuptake inhibitors (SSRIs), were developed decades ago. Psychological therapies such as cognitive behavioural therapy have helped many patients, but a significant number continue to experience symptoms despite treatment.Researchers say this reflects how little has been understood about anxiety’s underlying biology.
A roadmap for future treatments
The newly identified genetic regions could help change that.Instead of relying largely on trial and error to develop medicines, scientists now have dozens of biological targets to investigate.Many of the genes identified are involved in communication between brain cells, offering potential pathways for developing treatments that target the biology of anxiety rather than simply reducing symptoms.Researchers caution that the discovery will not immediately lead to new medicines. The next stage will involve laboratory research to understand what these genes actually do inside brain cells, followed by animal studies and, if promising targets emerge, eventually clinical trials.Some of the newly identified regions had never previously been linked to anxiety, opening entirely new directions for research.
The next chapter in anxiety genetics
The researchers say the study marks an important starting point rather than the end of the journey.Future studies involving larger and more diverse populations will be needed, as the current research included only people of European ancestry. Scientists also expect even larger international datasets to reveal additional genetic regions linked to anxiety.For now, the study provides something anxiety research has lacked for decades: a detailed genetic map.Rather than claiming anxiety has finally been explained, the findings give researchers 74 new locations in the human genome to investigate, including 39 that had never before been connected to the condition, offering fresh clues into the biology of anxiety and new avenues for developing better treatments.
