Researchers identify new genetic risk factors for depression. Here’s what that means
Nearly 300 new genetic variants have been linked to depression, according to a new study that included a large sample of nearly 5 million people.
The international team, led by researchers at the University of Edinburgh and King’s College London analysed genetic data from 680,000 people with depression and 4 million without depression across 29 countries.
This type of study looks at people’s DNA and genetic markers to see if genetic variants are linked to a specific trait or disease, in this case, depression.
The researchers found 697 genetic variations, or differences in gene sequences, 293 of which were new discoveries.
The study linked 308 specific genes to a higher risk of depression, according to the findings published this week in the journal Cell.
The associated genes were linked to neurons, a type of brain cell, found in areas like the amygdala and hippocampus.
Related
“Depression is a highly prevalent disorder and we still have a lot to learn about its biological underpinnings,” Cathryn Lewis, a professor of genetic epidemiology and statistics at King's College London and the study’s co-lead, said in a statement.
“These findings show depression is highly polygenic and open up downstream pathways to translate these findings into better care for people with depression,” she added.
The study’s authors said that one in four participants was from a non-European background representing a diverse cohort.
Though genetics is a factor in depression, it can also highly depend on social and psychological factors.
Risk factors for depression also include traumatic or stressful events, a history of other mental health disorders, and substance abuse, according to the US-based medical centre Mayo Clinic.
Related
Dr Jacob Crouse, a senior research fellow at the University of Sydney's Brain and Mind Centre who was not involved in the study, told Euronews Health in an e-mail that the study was "an exciting and inspiring testament to the power of global collaboration".
"Ultimately, these discoveries are demonstrating clearly that ‘depression’ is a highly complex family of conditions - not one single illness - that may be caused by many different processes gone wrong at different times during the life course,” he added.
A better understanding of depression
“Many researchers and clinicians are excited by the prospect of using 'polygenic risk scores' in the clinic, which are an aggregation of an individual's molecular genetic risk for a given condition (or set of conditions),” Crouse added.
This type of predictive tool, in the context of young mental health clinics for instance, could help to tell if a person “is on the track toward a serious type of mental health condition”.
However, the research isn’t there yet and he underlined “that genetic risk is not deterministic".
“Someone may be at very high genetic risk for a depressive disorder but not develop it for complex reasons which may be impossible to know at the individual level,” he added.
"It could be potentially harmful for clinicians to inform this person of their genetic risk - so there are tradeoffs that need to be carefully weighed".
Related
Around 7 per cent of Europeans suffer from chronic depression, according to 2019 data, with women being more impacted than men.
Treatments for depression can include therapy or medication for moderate or severe depression.
“While depression is a growing major health issue, we lack the insights needed to better treat and prevent it,” Dr Brittany Mitchell, a researcher at the Queensland Institute of Medical Research (QIMR) Berghofer in Australia, said in a statement.
“Larger, more inclusive studies like this will help us develop better treatments and interventions, ultimately improving lives and reducing the global impact of the condition”.
“It will also reinforce the evidence that mental health conditions are as biologically based as other conditions like heart disease,” Mitchell, who is part of the team analysing the data, added.
