With the winter months crawling on and the nights remaining dark, those of us who are struggling with depression may be having a hard time mentally – and the condition is on the rise.
The number of new people given sickness benefits for mental health conditions each month has more than doubled since 2020, indicating an overall decline in the UK’s mental health. Tony Blair stated this week that he believes many are “self-diagnosing” with mental health conditions and that they are mistaking “the challenges of life” with clinical depression.
But a new global study may have revealed genetic causes of depression which can be found in our DNA, going far beyond the idea that day-to-day life is the cause of poor mental health.
The world’s largest and most diverse genetic study, published today (January 14), into depression involved five million participants. It revealed nearly 300 previously unknown genetic links to the condition, giving hope for the improvement of future treatments.
“Genetic variation” refers to a small difference in the DNA that makes up a gene. One hundred of these newly discovered variations were identified due to the inclusion of people from African, East Asian, Hispanic and South Asian descent in the study.
Five million people’s genetic data across 29 countries was studied by researchers at Edinburgh University and King’s College London. These scientists believe their findings can present new targets for the treatment of depression and offer previously undiscovered insight into the mental health condition.
While previous research into the genetics of depression focused primarily on white populations, a quarter of the study’s participants were from non-European ancestries.
Scientists believe that therapies which take a genetic approach to the condition may not be effective for different ethnicities, contributing to health inequalities.
Each of these newly discovered genetic variants has a very small effect on the overall risk of developing the condition. But people who possess multiple variants in their DNA are more likely to become depressed, as the effects of multiple variants add up.
An individual’s risk of depression was more accurately predicted by scientists when taking into account these newly identified genetic variants. Almost half of the 700 genetic variations that were associated with the development of depression had not been associated with the condition before.
The genetic variants were also linked to areas of the brain that control emotion. It is hoped that this could offer new possible treatment targets for depression.
Further studies and clinical trials are needed to explore possible drugs to treat the condition, but it is thought that Pregabalin, used for chronic pain, and Modafinil, used for narcolepsy, could potentially be repurposed for helping with depression.
The research team from the Psychiatric Genomics Consortium involved scientists from all over the world. These included studies from South Africa, Brazil, Mexico, the US, Australia, Taiwan and China.
Professor Andrew McIntosh, study co-lead, from the University of Edinburgh’s Centre for Clinical Brain Sciences, said: “There are huge gaps in our understanding of clinical depression that limit opportunities to improve outcomes for those affected.
“Larger and more globally representative studies are vital to provide the insights needed to develop new and better therapies, and prevent illness in those at higher risk of developing the condition.”
Professor Cathryn Lewis, study co-lead, from the Institute of Psychiatry, Psychology and Neuroscience at King’s College London, said: “Depression is a highly prevalent disorder and we still have a lot to learn about its biological underpinnings. Our study identifies hundreds of additional genetic variants that play a role in depression.
“These findings show depression is highly polygenic and open up downstream pathways to translate these findings into better care for people with depression.”
If you need someone to talk to, call Samaritans at 116 123
Don’t miss the latest news from around Scotland and beyond – Sign up to our newsletter here.