It’s estimated that one in four adults will suffer from some type of anxiety disorder at some point, such as phobias of specific things; generalized anxiety that affects people over a long period of time; or panic disorder that involves sudden and severe anxiety attacks. These conditions can be very challenging to treat because we are still learning about the biological mechanisms underlying various types of anxiety. Now, scientists have shown how complex anxiety can be by performing a genetic analysis of hundreds of thousands of people.
In this study, which was reported in Nature Genetics, researchers assessed genetic data from over 120,000 anxiety disorder patients, and around 725,000 unaffected individuals. This showed that there is not one anxiety gene, but instead small changes in many genes are related to anxiety. There were 58 genetic variants that were associated with anxiety, and each could have a small influence on the disorder. There were many variants that overlap with other psychological traits or disorders, including depression, post-traumatic stress disorder, neuroticism, and suicide attempts. This may help explain why so many of these disorders can arise in the same person.
The work indicated that GABAergic signaling genes are related to anxiety disorders. GABA has already been associate with anxiety and some anti-anxiety drugs target GABA signaling, which helps control brain activity.
"The results provide evidence for the role of a number of previously unknown molecular signaling pathways in the etiology of anxiety that go beyond the GABAergic signaling pathway. They form the basis for future studies in cell cultures, animal models and in humans, which will contribute to a better understanding of the neurobiology of anxiety and thus to innovative and individualized therapies,” said co-corresponding study author Professor Jürgen Deckert of the University Medical Center Würzburg.
Although the findings do not point to a diagnostic test for anxiety that relates to genetics, it does help reveal more about the biological basis of the disorder. It may help scientists develop better treatments by learning more about the genes that can affect anxiety as well.
"At a time when anxiety is rapidly increasing in young people, it is crucial to deepen our understanding of what makes people biologically vulnerable. I hope that in time, data like this can help identify people who are particularly vulnerable so that we can intervene early,” said co-corresponding study author Professor Thalia Eley from King's College London.
Sources: King's College London, Nature Genetics