New research out of Australia has confirmed a shared "genetic architecture" between depression and anxiety.
The research, led by the QIMR Berghofer Medical Research Institute, looked at genomic data from more than 400,000 participants in the UK Biobank who reported symptoms of depression and anxiety.
It was then replicated and validated in an independent group of 1.9 million people who had self-reported whether they had been diagnosed with the mental health conditions to a personal genomic and biotechnological company.
The study found that of the 674 genes associated with either health condition, "about three-quarters" of the genes - or 509 - were shared, the senior researcher and head of QIMR Berghofer’s Translational Neurogenomics Group, professor Eske Derks, said today in a media release.
The study, published overnight in journal Nature Human Behaviour, is the first to identify the many shared genes between them.
Derks said that depression and anxiety are the two most prevalent psychiatric disorders in the world and often co-occur together in the same person.
“Not a lot has been known, until now, about the genetic causes of why people may suffer from depression and anxiety. Both disorders are highly comorbid conditions, with about three-quarters of people with an anxiety disorder also exhibiting symptoms of major depressive disorder,” she said.
“The better our understanding of the genetic basis of these psychiatric conditions, the more likely we are to be able to treat them," Derks said.
"It’s been observed in the past that people who have both depression and anxiety have more severe symptoms, have the illnesses for longer and are more resistant to treatments. We hope this study will help identify existing drugs that might be re-purposed to better target the genetic basis of depression and anxiety.”
QIMR Berghofer’s Translational Neurogenomics Group lead researcher, Jackson Thorp, said the group examined the genetic relationship between 28 individual symptoms related to depression and anxiety to understand how they overlapped.
“These kinds of complex disorders are influenced by large numbers of genes, with each having a small individual effect, which is why we needed a very large sample size to get a clear picture of the genetic influences on these disorders,” he said.
“While many genes are shared between anxiety and depression, we also found genes that are specific to each disorder.”