In the largest and most comprehensive study of its kind, researchers have successfully identified two novel genetic variants that could increase risk for the five primary anxiety disorders. The findings are the result of an international collaboration among 34 researchers from Virginia Commonwealth University and throughout academic institutions in the United States, Europe and Australia.

The international research team looked at genetic risk factors that are common across the five primary anxiety disorders identified in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, which are generalized anxiety disorder, panic disorder, agoraphobia, social phobia and specific phobias. Through a genome-wide association analysis of more than 18,000 subjects of European descent, the team was able to isolate two chromosomal regions that are associated with anxiety disorder risk.

The study, “Meta-Analysis of Genome-Wide Association Studies of Anxiety Disorders,” was published in the journal Molecular Psychiatry on Jan. 12.

“These findings are important because the two genetic regions were not previously known to be associated with anxiety disorder risk,” said senior author Jack Hettema, M.D., Ph.D., associate professor in the Department of Psychiatry at the VCU School of Medicine and faculty at the Virginia Institute for Psychiatric and Behavioral Geneticsat VCU. Hettema directs the VCU Health Anxiety Disorders Specialty Clinic, where he trains advanced psychiatric residents in the assessment and treatment of anxiety and comorbid disorders.

According to the National Institute of Mental Health, anxiety disorders are the most common mental illness in the U.S., affecting 40 million adults between the ages of 18 to 54 years old, or more than 18 percent of the population. Currently, anxiety disorders are treated pharmacologically either with antidepressants or sedatives as well as non-pharmacologically using cognitive behavioral therapies.

“Our gene-finding studies provide a new perspective on the neurobiological mechanisms by which anxiety disorders arise and point the way towards new ways to treat and possibly prevent them,” Hettema said.

While the findings are encouraging, they will need to be replicated in large independent samples before researchers can have complete confidence in the results. Hettema is currently working on replicating and further extending the findings from the study that was published this month.