New genetic links to anxiety symptoms have been uncovered in the largest study of its kind to date.
Researchers at QIMR Berghofer in Brisbane and King’s College London analysed the DNA of nearly 700,000 people of European ancestry to identify which genetic differences occur most in those who experience severe anxiety.
The study was published in Nature Human Behaviour, with lead author Professor Thalia Eley from King’s College London saying it was important to identify and understand sources of risk, given the high and rising rates of anxiety.
“We hope our findings encourage a new wave of large-scale analyses to accelerate our progress in understanding the genetic architecture of anxiety,” Prof Eley – Professor of Developmental Behaviour Genetics at Institute of Psychiatry, Psychology and Neuroscience said.
The study identified 74 locations in the genome where genetic differences were linked to anxiety symptoms – 39 of these were new.
The results also support the role of certain genes in anxiety which are active in the brain tissue and involved in how nerve cells communicate with each other.
The analysis found the genetic differences explained only around six percent of variations in symptom severity between people. This left substantial room for environmental influences, gene-environment interactions, and undetected genetic effects.
Dr Megan Skelton, a Research Fellow at King’s College London and first author on the study, said the results showed someone with a high genetic risk might never develop anxiety, and someone with a low risk could.
“Genetic influences work alongside and interplay with life experiences, social contexts, and psychological factors to shape individual risk,” Dr Skelton said.
“The rise we’re seeing in anxiety rates points to environmental factors, and understanding genetic risk can help us identify who may be most vulnerable.”
There was a broad range of significant genetic correlations of anxiety with both mental and physical health conditions, including depression, irritable bowel syndrome, chronic pain, coronary artery disease, endometriosis and migraine.
Dr Brittany Mitchell, Team Head of the Complex Trait Genomics group at QIMR Berghofer and co-first author on the study, said these correlations highlighted the connection between mental and physical health.
“Importantly, while some shared genetic variants may increase risk for both a physical health condition and more severe anxiety symptoms, it’s also true that living with chronic pain or illness can contribute to anxiety symptoms,” Dr Mitchell said.
“Our findings don’t reveal causation or the direction of effect, but they do open up important questions for future research.”
