Panic disorder is a severe form of anxiety in which the affected individual feels an abrupt onset of fear, often accompanied by profound physical symptoms of discomfort. Scientists have known from studying twins that genes contribute to the risk of panic disorder, but very little is known about which specific genes are involved.
Studies have shown that breathing air that has increased levels of carbon dioxide can trigger panic attacks in most people with panic disorder as opposed to people without the disorder.
One theory is that panic disorder involves an overly sensitive “Suffocation alarm system” in the brain that evolved to protect us from suffocating, and that panic attacks result when this alarm gets triggered by signals of impending suffocation like rising carbon dioxide levels.
The researchers genotyped and compared variants in ACCN2 in 414 individuals with panic disorder and 846 healthy controls.
Dr. Bruce M. Cohen, co-senior author and Professor of Psychiatry at Harvard Medical School, added, “Taken together, our results suggest that the ASIC1a gene is a risk gene for panic disorder, as well as for the structure and function of the amygdala and its reaction to threat. They also raise the possibility that drugs that inhibit or modulate ASIC1a might be helpful in the treatment of panic or other forms of anxiety and fear.”
Dr. John Krystal, Editor of Biological Psychiatry, commented, “Once again we see that a mechanism that is implicated in the generation of fear and the risk for anxiety disorders has its basis in a fundamental survival mechanism. This important new study continues to build our understanding of the underpinnings of anxiety disorders that affect so many people in our society.”