Depression: is it in our genes?

Groundbreaking findings by a study published in Nature Genetics have for the first time suggested a location for genes linked with an increased risk of depression. The study, comprising over 75,000 patients, found 15 regions and 17 specific locations with statistically significant commonality in those with depression. Some of these regions were located near to regions associated with neuron (brain cell) development. Although the authors of the study stress that these genes do not cause depression, it is suggested that they may increase the risk of developing the disease.

Depression is a remarkably common condition with an unclear cause, with genetic, evolutionary, biological and social explanations offered. Symptoms are debilitating and often include low mood, low energy, reduced eating and sleeping and social withdrawal. Extreme and untreated depression is linked with an increased risk of suicide, especially in men. Treatment is stepwise and can comprise individually directed CBT or meditation, lifestyle changes such as exercise and alcohol reduction, therapy and medication. Severe depression is treated under psychiatrists

These findings may shed some light on the cause of depression, as well as opening doors to new treatments and research. It is long known that differences in neurotransmitters and hormones are present in depressed patients and that there is a higher risk of depression within families. Evolutionary arguments emphasise the role of depression as a subordinate behaviour increasing personal and group survival within social groups, promoting further reproductive survival of the species as a whole. Arguments favouring a genetic explanation of depression through the ‘passing on’ for genes contributing to ‘adaptive’ behaviour such as this find new strength in the results of this study.

Furthermore, there is potential for further research afforded by these findings. Statistical analysis of gigantic anonymously formed data banks has expansive potential for the evaluation of the genetic cause of disease. As diagnostic and investigatory technology increases, our lens of the world becomes more magnified, with the genetic lineage of common disease under the microscope. One of the most exciting developments of this research is opening the door for this method of investigation.

"These findings build on a growing body of highly sophisticated research aiming to unlock the causes of depression. We grow ever closer to personalised medicine in psychiatry". Dr Stephen Barratt, junior psychiatrist

These findings may be the start of a revolution in the management of depression. A greater understanding of the biology of depression will likely lead to better medical treatments. With depression on the rise, a cost-effective and efficient treatment pathway is needed more than ever. Even if these findings only point toward a behavioural explanation of depression, recognition of these genes through screening may lead to earlier identification and treatment. Whatever the future holds for depression, it seems this examination of the record of our past may pave the way.

Any opinions above are the author's alone. Guidance is based the best available evidence at the time of writing All data are based on externally validated studies unless expressed otherwise. Novel data are representative of sample surveyed. Online recommendation is no substitute for seeing your own doctor and should not be taken as medical advice. Review any new exercise or diet regime with your primary healthcare provider

Dr Ben Janaway MBChB is a young NHS doctor in the Southwest. His interests include neurology, health communication, and medical ethics. He is also an avid advocate of compassionate care and quality improvement, running a project in the Southwest around medical humanities. Please follow and support: Dr Janaway on Facebook Dr Janaway on Twitter 

Sources

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